fix: show night icons for hourly forecast

fix: default wind unit to kmh
feat: add temperature unit preference
2026-06-13 21:27:41 +02:00 · 2026-06-13 21:21:52 +02:00 · 2026-06-13 21:05:01 +02:00
25 changed files with 207 additions and 85 deletions
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -49,6 +49,7 @@ Repozytorium nie ma obecnie skryptu testów ani formattera. `npm run typecheck`
 - Listy ostrzeżeń zachowują priorytet lokalnego obszaru, a wewnątrz każdej grupy pokazują ostrzeżenia meteorologiczne przed hydrologicznymi. Jeśli lokalizacja ma rozpoznany powiat TERYT, ostrzeżenia meteo filtruj po tym powiecie; w przeciwnym razie stosuj fallback wojewódzki. W obrębie rodzaju zachowuj kolejność publikacji od najnowszych.
 - Dashboard pokazuje kompaktowo wyłącznie aktywne i nadchodzące ostrzeżenia meteo dla wybranego obszaru. Filtruj je po `validTo` względem czasu przeglądarki i automatycznie usuwaj wygasłe komunikaty bez przeładowania strony.
 - Brief dnia i brief na jutro generuj deterministycznie w `lib/weather-brief.ts` z prognozy modelowej i ostrzeżeń IMGW. Nie traktuj ich jako odpowiedzi modelu AI i nie wymagaj klucza OpenAI API. Brief na jutro korzysta z pełnego jutrzejszego dnia prognozy i może informować o burzach na podstawie kodów modelu także bez oficjalnego ostrzeżenia IMGW.
+- Preferencje jednostek temperatury i wiatru są ustawieniami prezentacyjnymi. Dane źródłowe oraz progi logiki pogody pozostają liczone w `°C` i `m/s`, a wybrane jednostki zapisuj w subskrypcji Web Push, żeby briefy serwerowe używały tego samego formatu co UI.
 - Powiadomienia Web Push o ostrzeżeniach meteo, porannym briefie i wieczornym briefie na jutro konfiguruj przez `/settings`, `public/sw.js`, route handlery `app/api/notifications/*`, w tym testowy `/api/notifications/test`, oraz self-hostowany worker `scripts/notification-worker.mjs`. Endpointy harmonogramu nie uruchamiają się same bez workera albo zewnętrznego crona. Wymagają kluczy VAPID w zmiennych środowiskowych. iOS/iPadOS wymaga PWA z ekranu początkowego, ale Android i desktop nie powinny być blokowane wymogiem `standalone`. Obecny `lib/push-store.ts` jest pamięciowy i przed produkcją musi zostać zastąpiony trwałym magazynem subskrypcji.
 - GPS wymaga świadomej zgody użytkownika i HTTPS. Zaokrąglaj współrzędne przed użyciem i utrzymuj widoczną atrybucję OpenStreetMap dla reverse geocodingu Nominatim.
 - Normalizuj zewnętrzne odpowiedzi i obsługuj `null`, puste pola oraz błędne wartości. Brak danych pokazuj jawnie zamiast uzupełniać estymacją.
--- a/app/api/notifications/daily-brief/route.ts
+++ b/app/api/notifications/daily-brief/route.ts
@@ -4,7 +4,7 @@ import { fetchMeteoWarnings } from "@/lib/server-warnings";
 import { getPushSubscriptions, hasSentMorningBrief, markMorningBriefSent, removePushSubscription } from "@/lib/push-store";
 import { isWebPushConfigured, sendMorningBriefNotification } from "@/lib/push-service";
 import { buildWeatherBrief } from "@/lib/weather-brief";
-import { DEFAULT_WIND_SPEED_UNIT } from "@/lib/weather-utils";
+import { DEFAULT_TEMPERATURE_UNIT, DEFAULT_WIND_SPEED_UNIT } from "@/lib/weather-utils";

 export const runtime = "nodejs";

@@ -67,6 +67,7 @@ export async function GET(request: Request) {
        countyTeryt: subscription.countyTeryt,
        locationName: subscription.locationName ?? "wtr.",
        language: subscription.language,
+        temperatureUnit: subscription.temperatureUnit ?? DEFAULT_TEMPERATURE_UNIT,
        windSpeedUnit: subscription.windSpeedUnit ?? DEFAULT_WIND_SPEED_UNIT,
        now,
      });
--- a/app/api/notifications/subscriptions/route.ts
+++ b/app/api/notifications/subscriptions/route.ts
@@ -2,7 +2,7 @@ import { NextResponse } from "next/server";
 import { upsertPushSubscription, removePushSubscription } from "@/lib/push-store";
 import { isWebPushConfigured } from "@/lib/push-service";
 import { normalizeProvinceName } from "@/lib/provinces";
-import { DEFAULT_WIND_SPEED_UNIT, isWindSpeedUnit } from "@/lib/weather-utils";
+import { DEFAULT_TEMPERATURE_UNIT, DEFAULT_WIND_SPEED_UNIT, isTemperatureUnit, isWindSpeedUnit } from "@/lib/weather-utils";
 import type { Language } from "@/lib/i18n";
 import type { BrowserPushSubscription } from "@/types/notifications";

@@ -33,11 +33,13 @@ export async function POST(request: Request) {
    longitude?: unknown;
    locationName?: unknown;
    countyTeryt?: unknown;
+    temperatureUnit?: unknown;
    windSpeedUnit?: unknown;
  } | null;
  const subscription = body?.subscription;
  const province = normalizeProvinceName(typeof body?.province === "string" ? body.province : null);
  const language: Language = body?.language === "en" ? "en" : "pl";
+  const rawTemperatureUnit = body?.temperatureUnit;
  const rawWindSpeedUnit = body?.windSpeedUnit;

  if (!isBrowserPushSubscription(subscription) || !province) {
@@ -57,6 +59,7 @@ export async function POST(request: Request) {
    longitude: typeof body?.longitude === "number" && Number.isFinite(body.longitude) ? body.longitude : null,
    locationName: typeof body?.locationName === "string" && body.locationName.trim() ? body.locationName.trim().slice(0, 80) : null,
    countyTeryt: typeof body?.countyTeryt === "string" && /^\d{4}$/.test(body.countyTeryt) ? body.countyTeryt : null,
+    temperatureUnit: isTemperatureUnit(rawTemperatureUnit) ? rawTemperatureUnit : DEFAULT_TEMPERATURE_UNIT,
    windSpeedUnit: isWindSpeedUnit(rawWindSpeedUnit) ? rawWindSpeedUnit : DEFAULT_WIND_SPEED_UNIT,
    createdAt: now,
    updatedAt: now,
--- a/app/api/notifications/tomorrow-brief/route.ts
+++ b/app/api/notifications/tomorrow-brief/route.ts
@@ -4,7 +4,7 @@ import { fetchMeteoWarnings } from "@/lib/server-warnings";
 import { getPushSubscriptions, hasSentTomorrowBrief, markTomorrowBriefSent, removePushSubscription } from "@/lib/push-store";
 import { isWebPushConfigured, sendTomorrowBriefNotification } from "@/lib/push-service";
 import { buildTomorrowWeatherBrief } from "@/lib/weather-brief";
-import { DEFAULT_WIND_SPEED_UNIT } from "@/lib/weather-utils";
+import { DEFAULT_TEMPERATURE_UNIT, DEFAULT_WIND_SPEED_UNIT } from "@/lib/weather-utils";

 export const runtime = "nodejs";

@@ -77,6 +77,7 @@ export async function GET(request: Request) {
        countyTeryt: subscription.countyTeryt,
        locationName: subscription.locationName ?? "wtr.",
        language: subscription.language,
+        temperatureUnit: subscription.temperatureUnit ?? DEFAULT_TEMPERATURE_UNIT,
        windSpeedUnit: subscription.windSpeedUnit ?? DEFAULT_WIND_SPEED_UNIT,
        now,
      });
--- a/components/charts/day-forecast-charts.tsx
+++ b/components/charts/day-forecast-charts.tsx
@@ -5,6 +5,8 @@ import { Card } from "@/components/ui/card";
 import { CHART_COLORS } from "@/lib/chart-theme";
 import { useI18n } from "@/lib/i18n";
 import { formatForecastRainfall, formatForecastTemperature } from "@/lib/forecast-utils";
+import { useWeatherStore } from "@/lib/store";
+import { convertTemperature, formatTemperatureValue, getTemperatureUnitLabel } from "@/lib/weather-utils";
 import type { HourlyForecast } from "@/types/forecast";

 const INITIAL_CHART_DIMENSION = { width: 1, height: 1 };
@@ -15,13 +17,15 @@ function formatHour(value: string) {

 export function DayForecastCharts({ hours }: { hours: HourlyForecast[] }) {
  const { language, t } = useI18n();
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const rows = hours.map((hour) => ({
    time: formatHour(hour.time),
-    temperature: hour.temperature,
-    feelsLike: hour.feelsLike,
+    temperature: hour.temperature === null ? null : convertTemperature(hour.temperature, temperatureUnit),
+    feelsLike: hour.feelsLike === null ? null : convertTemperature(hour.feelsLike, temperatureUnit),
    precipitation: hour.precipitation,
    precipitationProbability: hour.precipitationProbability,
  }));
+  const temperatureUnitLabel = getTemperatureUnitLabel(temperatureUnit);

  return (
    <div className="grid gap-3 lg:grid-cols-2">
@@ -33,10 +37,14 @@ export function DayForecastCharts({ hours }: { hours: HourlyForecast[] }) {
            <ComposedChart data={rows} margin={{ left: -20, right: 8, top: 8 }}>
              <CartesianGrid stroke={CHART_COLORS.grid} strokeDasharray="4 4" vertical={false} />
              <XAxis dataKey="time" axisLine={false} tickLine={false} interval={3} tick={{ fill: "currentColor", fontSize: 11 }} />
-              <YAxis axisLine={false} tickLine={false} tick={{ fill: "currentColor", fontSize: 11 }} unit="°" />
+              <YAxis axisLine={false} tickLine={false} tick={{ fill: "currentColor", fontSize: 11 }} unit={temperatureUnitLabel} />
              <Tooltip
                contentStyle={{ borderRadius: 14, border: `1px solid ${CHART_COLORS.tooltipBorder}`, background: CHART_COLORS.tooltipBackground, color: CHART_COLORS.tooltipText }}
-                formatter={(value) => [formatForecastTemperature(typeof value === "number" ? value : null, language)]}
+                formatter={(value) => [
+                  typeof value === "number"
+                    ? formatTemperatureValue(value, language, temperatureUnit)
+                    : formatForecastTemperature(null, language, temperatureUnit),
+                ]}
              />
              <Legend wrapperStyle={{ fontSize: "0.72rem" }} />
              <Line type="monotone" dataKey="temperature" name={t("forecast.temperature")} stroke={CHART_COLORS.temperature} strokeWidth={3} dot={false} connectNulls />
--- a/components/dashboard/weather-brief-card.tsx
+++ b/components/dashboard/weather-brief-card.tsx
@@ -20,17 +20,18 @@ export function WeatherBriefCard({ latitude, longitude, locationName }: { latitu
  const { data: warnings = [] } = useWarnings();
  const selectedStationId = useWeatherStore((state) => state.selectedStationId);
  const selectedLocation = useWeatherStore((state) => state.selectedLocation);
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const windSpeedUnit = useWeatherStore((state) => state.windSpeedUnit);
  const province = getProvinceForSelection(selectedLocation?.province, selectedStationId ?? DEFAULT_STATION_ID);

  const brief = useMemo(() => {
    if (!forecast) return null;
-    return buildWeatherBrief({ forecast, warnings, province, countyTeryt: selectedLocation?.countyTeryt, locationName, language, windSpeedUnit });
-  }, [forecast, language, locationName, province, selectedLocation?.countyTeryt, warnings, windSpeedUnit]);
+    return buildWeatherBrief({ forecast, warnings, province, countyTeryt: selectedLocation?.countyTeryt, locationName, language, temperatureUnit, windSpeedUnit });
+  }, [forecast, language, locationName, province, selectedLocation?.countyTeryt, temperatureUnit, warnings, windSpeedUnit]);
  const tomorrowBrief = useMemo(() => {
    if (!forecast) return null;
-    return buildTomorrowWeatherBrief({ forecast, warnings, province, countyTeryt: selectedLocation?.countyTeryt, locationName, language, windSpeedUnit });
-  }, [forecast, language, locationName, province, selectedLocation?.countyTeryt, warnings, windSpeedUnit]);
+    return buildTomorrowWeatherBrief({ forecast, warnings, province, countyTeryt: selectedLocation?.countyTeryt, locationName, language, temperatureUnit, windSpeedUnit });
+  }, [forecast, language, locationName, province, selectedLocation?.countyTeryt, temperatureUnit, warnings, windSpeedUnit]);

  if (!Number.isFinite(latitude) || !Number.isFinite(longitude) || isPending) {
    return <LoadingSkeleton className="h-48" />;
--- a/components/forecast/day-forecast-modal.tsx
+++ b/components/forecast/day-forecast-modal.tsx
@@ -14,6 +14,7 @@ import {
  formatForecastTemperature,
  formatForecastWind,
  getForecastCondition,
+  isForecastNight,
 } from "@/lib/forecast-utils";
 import { useWeatherStore } from "@/lib/store";
 import type { DailyForecast, ForecastSource, HourlyForecast } from "@/types/forecast";
@@ -54,6 +55,7 @@ export function DayForecastModal({
  onClose: () => void;
 }) {
  const { language, locale, t } = useI18n();
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const windSpeedUnit = useWeatherStore((state) => state.windSpeedUnit);
  const closeButtonRef = useRef<HTMLButtonElement>(null);
  const portalRoot = typeof document === "undefined" ? null : document.body;
@@ -131,8 +133,8 @@ export function DayForecastModal({
                      <p className="text-sm text-muted">{getForecastCondition(day.weatherCode, language)}</p>
                      <div className="mt-2 flex items-end gap-4">
                        <ForecastIcon code={day.weatherCode} className="mb-2 size-14 text-accent" />
-                        <p className="text-6xl font-semibold tracking-[-0.08em] sm:text-7xl">{formatForecastTemperature(day.temperatureMax, language)}</p>
-                        <p className="mb-2 text-2xl text-muted">{formatForecastTemperature(day.temperatureMin, language)}</p>
+                        <p className="text-6xl font-semibold tracking-[-0.08em] sm:text-7xl">{formatForecastTemperature(day.temperatureMax, language, temperatureUnit)}</p>
+                        <p className="mb-2 text-2xl text-muted">{formatForecastTemperature(day.temperatureMin, language, temperatureUnit)}</p>
                      </div>
                    </div>
                    <div className="grid grid-cols-2 gap-2 sm:min-w-[22rem]">
@@ -155,8 +157,8 @@ export function DayForecastModal({
                          title={getForecastCondition(hour.weatherCode, language)}
                        >
                          <p className="text-xs font-medium text-muted">{formatHour(hour.time)}</p>
-                          <ForecastIcon code={hour.weatherCode} className="mx-auto my-3 size-6 text-accent" />
-                          <p className="text-lg font-semibold tracking-tight">{formatForecastTemperature(hour.temperature, language)}</p>
+                          <ForecastIcon code={hour.weatherCode} isNight={isForecastNight(hour.time, day)} className="mx-auto my-3 size-6 text-accent" />
+                          <p className="text-lg font-semibold tracking-tight">{formatForecastTemperature(hour.temperature, language, temperatureUnit)}</p>
                          <p className="mt-2 flex items-center justify-center gap-1 text-[0.66rem] text-accent">
                            <Droplets className="size-3" />
                            {hour.precipitationProbability === null ? "—" : `${hour.precipitationProbability}%`}
--- a/components/forecast/forecast-icon.tsx
+++ b/components/forecast/forecast-icon.tsx
@@ -1,8 +1,8 @@
-import { Cloud, CloudDrizzle, CloudFog, CloudLightning, CloudRain, CloudSnow, CloudSun, Sun } from "lucide-react";
+import { Cloud, CloudDrizzle, CloudFog, CloudLightning, CloudMoon, CloudRain, CloudSnow, CloudSun, MoonStar, Sun } from "lucide-react";

-export function ForecastIcon({ code, className = "" }: { code: number | null; className?: string }) {
-  const Icon = code === 0 ? Sun
-    : code === 1 || code === 2 ? CloudSun
+export function ForecastIcon({ code, className = "", isNight = false }: { code: number | null; className?: string; isNight?: boolean }) {
+  const Icon = code === 0 ? isNight ? MoonStar : Sun
+    : code === 1 || code === 2 ? isNight ? CloudMoon : CloudSun
      : code === 45 || code === 48 ? CloudFog
        : code !== null && code >= 51 && code <= 57 ? CloudDrizzle
          : code !== null && ((code >= 61 && code <= 67) || (code >= 80 && code <= 82)) ? CloudRain
--- a/components/forecast/forecast-panel.tsx
+++ b/components/forecast/forecast-panel.tsx
@@ -17,9 +17,11 @@ import {
  formatForecastRainfall,
  formatForecastTemperature,
  formatForecastWind,
+  getDailyForecastForHour,
  getForecastCondition,
  getHourlyForecastForDay,
  getUpcomingHourlyForecast,
+  isForecastNight,
 } from "@/lib/forecast-utils";
 import { useWeatherStore } from "@/lib/store";
 import type { DailyForecast, HourlyForecast } from "@/types/forecast";
@@ -60,6 +62,7 @@ function HourlySummaryMetric({ icon: Icon, label, value }: { icon: LucideIcon; l

 function HourlyForecastSummary({ hours }: { hours: HourlyForecast[] }) {
  const { language, t } = useI18n();
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const windSpeedUnit = useWeatherStore((state) => state.windSpeedUnit);
  const minimumTemperature = getMinimum(hours.map((hour) => hour.temperature));
  const maximumTemperature = getMaximum(hours.map((hour) => hour.temperature));
@@ -68,7 +71,7 @@ function HourlyForecastSummary({ hours }: { hours: HourlyForecast[] }) {
  const maximumRainfallProbability = getMaximum(hours.map((hour) => hour.precipitationProbability));
  const temperatureRange = minimumTemperature === null || maximumTemperature === null
    ? "—"
-    : `${formatForecastTemperature(minimumTemperature, language)} / ${formatForecastTemperature(maximumTemperature, language)}`;
+    : `${formatForecastTemperature(minimumTemperature, language, temperatureUnit)} / ${formatForecastTemperature(maximumTemperature, language, temperatureUnit)}`;

  return (
    <div className="mt-auto hidden border-t border-border/70 pt-4 lg:block">
@@ -85,6 +88,7 @@ function HourlyForecastSummary({ hours }: { hours: HourlyForecast[] }) {

 function DailyForecastRow({ day, index, onSelect }: { day: DailyForecast; index: number; onSelect: (day: DailyForecast) => void }) {
  const { language, locale, t } = useI18n();
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const label = formatDay(day.date, locale, t("forecast.today"), index);
  return (
    <motion.li
@@ -106,7 +110,7 @@ function DailyForecastRow({ day, index, onSelect }: { day: DailyForecast; index:
          <span className="truncate text-xs text-muted">{getForecastCondition(day.weatherCode, language)} · {formatForecastRainfall(day.precipitation, language)}</span>
        </div>
        <span className="hidden items-center gap-1 text-xs text-accent sm:flex"><Droplets className="size-3" />{day.precipitationProbability === null ? "—" : `${day.precipitationProbability}%`}</span>
-        <p className="whitespace-nowrap text-sm"><strong>{formatForecastTemperature(day.temperatureMax, language)}</strong><span className="ml-2 text-muted">{formatForecastTemperature(day.temperatureMin, language)}</span></p>
+        <p className="whitespace-nowrap text-sm"><strong>{formatForecastTemperature(day.temperatureMax, language, temperatureUnit)}</strong><span className="ml-2 text-muted">{formatForecastTemperature(day.temperatureMin, language, temperatureUnit)}</span></p>
        <ChevronRight className="hidden size-4 text-muted sm:block" />
      </motion.button>
    </motion.li>
@@ -115,6 +119,7 @@ function DailyForecastRow({ day, index, onSelect }: { day: DailyForecast; index:

 export function ForecastPanel({ latitude, longitude, locationName }: { latitude?: number; longitude?: number; locationName: string }) {
  const { language, t } = useI18n();
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const windSpeedUnit = useWeatherStore((state) => state.windSpeedUnit);
  const { data: forecast, isPending, isError, refetch } = useForecast(latitude, longitude);
  const [selectedDay, setSelectedDay] = useState<DailyForecast | null>(null);
@@ -150,7 +155,9 @@ export function ForecastPanel({ latitude, longitude, locationName }: { latitude?
              <h3 className="flex items-center gap-2 text-sm font-semibold"><Clock3 className="size-4 text-accent" />{t("forecast.hourly")}</h3>
              <div className="weather-scrollbar -mx-4 mt-4 overflow-x-auto px-4 pb-2 sm:-mx-5 sm:px-5 lg:mt-5">
                <ul className="flex min-w-max gap-2">
-                  {upcomingHours.map((hour, index) => (
+                  {upcomingHours.map((hour, index) => {
+                    const day = getDailyForecastForHour(forecast.daily, hour.time);
+                    return (
                      <motion.li
                        key={hour.time}
                        initial={{ opacity: 0, y: 8 }}
@@ -160,13 +167,13 @@ export function ForecastPanel({ latitude, longitude, locationName }: { latitude?
                        title={getForecastCondition(hour.weatherCode, language)}
                      >
                        <p className="text-xs font-medium text-muted">{formatHour(hour.time)}</p>
-                      <ForecastIcon code={hour.weatherCode} className="mx-auto my-3 size-6 text-accent" />
-                      <p className="text-lg font-semibold tracking-tight">{formatForecastTemperature(hour.temperature, language)}</p>
+                        <ForecastIcon code={hour.weatherCode} isNight={isForecastNight(hour.time, day)} className="mx-auto my-3 size-6 text-accent" />
+                        <p className="text-lg font-semibold tracking-tight">{formatForecastTemperature(hour.temperature, language, temperatureUnit)}</p>
                        <p className="mt-2 flex items-center justify-center gap-1 text-[0.66rem] text-accent"><Droplets className="size-3" />{hour.precipitationProbability === null ? "—" : `${hour.precipitationProbability}%`}</p>
                        <div className="mt-3 hidden space-y-1.5 border-t border-border/65 pt-3 text-[0.66rem] text-muted lg:block">
                          <p className="flex items-center justify-center gap-1" title={t("forecast.apparentTemperature")}>
                            <ThermometerSun className="size-3 text-accent" />
-                          {formatForecastTemperature(hour.feelsLike, language)}
+                            {formatForecastTemperature(hour.feelsLike, language, temperatureUnit)}
                          </p>
                          <p className="flex items-center justify-center gap-1" title={t("weather.wind")}>
                            <Wind className="size-3 text-accent" />
@@ -178,7 +185,8 @@ export function ForecastPanel({ latitude, longitude, locationName }: { latitude?
                          </p>
                        </div>
                      </motion.li>
-                  ))}
+                    );
+                  })}
                </ul>
              </div>
              <HourlyForecastSummary hours={upcomingHours} />
--- a/components/hydro/hydro-station-card.tsx
+++ b/components/hydro/hydro-station-card.tsx
@@ -6,9 +6,11 @@ import type { HydroStation } from "@/types/imgw";
 import { formatDateTime, formatFlow, formatTemperature, formatWaterLevel } from "@/lib/weather-utils";
 import { Card } from "@/components/ui/card";
 import { useI18n } from "@/lib/i18n";
+import { useWeatherStore } from "@/lib/store";

 export function HydroStationCard({ station, index = 0 }: { station: HydroStation; index?: number }) {
  const { language, t } = useI18n();
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  return (
    <motion.article initial={{ opacity: 0, y: 10 }} animate={{ opacity: 1, y: 0 }} transition={{ delay: Math.min(index * 0.02, 0.3), duration: 0.3 }}>
      <Card className="h-full p-4 transition duration-300 hover:-translate-y-1 hover:bg-surface-raised/90">
@@ -20,7 +22,7 @@ export function HydroStationCard({ station, index = 0 }: { station: HydroStation
        </div>
        <div className="mt-5 grid grid-cols-3 gap-2">
          <HydroMetric icon={Droplets} label={t("hydro.level")} value={formatWaterLevel(station.waterLevel, language)} />
-          <HydroMetric icon={Thermometer} label={t("hydro.water")} value={formatTemperature(station.waterTemperature, language)} />
+          <HydroMetric icon={Thermometer} label={t("hydro.water")} value={formatTemperature(station.waterTemperature, language, temperatureUnit)} />
          <HydroMetric icon={Activity} label={t("hydro.flow")} value={formatFlow(station.flow, language)} />
        </div>
        <p className="mt-4 text-[0.7rem] text-muted">{t("hydro.levelMeasurement", { date: formatDateTime(station.waterLevelMeasuredAt, language) })}</p>
--- a/components/settings/settings-page.tsx
+++ b/components/settings/settings-page.tsx
@@ -1,7 +1,7 @@
 "use client";

 import { useEffect, useMemo, useState } from "react";
-import { Bell, BellRing, Clock3, Languages, MapPinned, Palette, Settings, Smartphone, Wind } from "lucide-react";
+import { Bell, BellRing, Clock3, Languages, MapPinned, Palette, Settings, Smartphone, Thermometer, Wind } from "lucide-react";
 import type { LucideIcon } from "lucide-react";
 import { Button } from "@/components/ui/button";
 import { Card } from "@/components/ui/card";
@@ -15,9 +15,9 @@ import { locateSynopStations } from "@/lib/location-utils";
 import { decodeBase64UrlKey, deletePushSubscription, fetchVapidPublicKey, savePushSubscription, sendTestPushNotification } from "@/lib/notification-api";
 import { formatProvinceName, getProvinceForSelection, PROVINCES } from "@/lib/provinces";
 import { useWeatherStore } from "@/lib/store";
-import { WIND_SPEED_UNITS } from "@/lib/weather-utils";
+import { TEMPERATURE_UNITS, WIND_SPEED_UNITS } from "@/lib/weather-utils";
 import type { Province } from "@/types/province";
-import type { WindSpeedUnit } from "@/types/units";
+import type { TemperatureUnit, WindSpeedUnit } from "@/types/units";

 type NotificationSupportStatus = "checking" | "unconfigured" | "unsupported" | "needs-install" | "default" | "denied" | "granted";

@@ -108,6 +108,11 @@ const windSpeedUnitKeys: Record<WindSpeedUnit, "settings.units.wind.ms" | "setti
  mph: "settings.units.wind.mph",
 };

+const temperatureUnitKeys: Record<TemperatureUnit, "settings.units.temperature.c" | "settings.units.temperature.f"> = {
+  c: "settings.units.temperature.c",
+  f: "settings.units.temperature.f",
+};
+
 export function SettingsPage() {
  const { language, t } = useI18n();
  const [notificationStatus, setNotificationStatus] = useState<NotificationSupportStatus>("checking");
@@ -124,12 +129,14 @@ export function SettingsPage() {
  const tomorrowBriefEnabled = useWeatherStore((state) => state.tomorrowBriefNotificationsEnabled);
  const provinceMode = useWeatherStore((state) => state.warningNotificationProvinceMode);
  const manualProvince = useWeatherStore((state) => state.warningNotificationProvince);
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const windSpeedUnit = useWeatherStore((state) => state.windSpeedUnit);
  const setNotificationsEnabled = useWeatherStore((state) => state.setWarningNotificationsEnabled);
  const setMorningBriefEnabled = useWeatherStore((state) => state.setMorningBriefNotificationsEnabled);
  const setTomorrowBriefEnabled = useWeatherStore((state) => state.setTomorrowBriefNotificationsEnabled);
  const setProvinceMode = useWeatherStore((state) => state.setWarningNotificationProvinceMode);
  const setManualProvince = useWeatherStore((state) => state.setWarningNotificationProvince);
+  const setTemperatureUnit = useWeatherStore((state) => state.setTemperatureUnit);
  const setWindSpeedUnit = useWeatherStore((state) => state.setWindSpeedUnit);

  const selectedStation = stations?.find((station) => station.id === selectedStationId)
@@ -180,6 +187,7 @@ export function SettingsPage() {
        longitude: notificationLongitude,
        locationName: notificationLocationName,
        countyTeryt: notificationCountyTeryt,
+        temperatureUnit,
        windSpeedUnit,
      }).catch(() => undefined);
    }
@@ -188,7 +196,7 @@ export function SettingsPage() {
    return () => {
      cancelled = true;
    };
-  }, [effectiveProvince, language, morningBriefEnabled, notificationCountyTeryt, notificationLatitude, notificationLocationName, notificationLongitude, notificationStatus, notificationsEnabled, tomorrowBriefEnabled, vapidPublicKey, windSpeedUnit]);
+  }, [effectiveProvince, language, morningBriefEnabled, notificationCountyTeryt, notificationLatitude, notificationLocationName, notificationLongitude, notificationStatus, notificationsEnabled, temperatureUnit, tomorrowBriefEnabled, vapidPublicKey, windSpeedUnit]);

  const notificationStatusLabel = useMemo(() => {
    switch (notificationStatus) {
@@ -247,6 +255,7 @@ export function SettingsPage() {
        longitude: notificationLongitude,
        locationName: notificationLocationName,
        countyTeryt: notificationCountyTeryt,
+        temperatureUnit,
        windSpeedUnit,
      });
      setNotificationsEnabled(true);
@@ -310,6 +319,7 @@ export function SettingsPage() {
        longitude: notificationLongitude,
        locationName: notificationLocationName,
        countyTeryt: notificationCountyTeryt,
+        temperatureUnit,
        windSpeedUnit,
      });
    } catch {
@@ -331,6 +341,7 @@ export function SettingsPage() {
        longitude: notificationLongitude,
        locationName: notificationLocationName,
        countyTeryt: notificationCountyTeryt,
+        temperatureUnit,
        windSpeedUnit,
      });
    } catch {
@@ -353,6 +364,26 @@ export function SettingsPage() {
        <SettingsRow icon={Palette} title={t("settings.theme.title")} description={t("settings.theme.description")}>
          <ThemeToggle />
        </SettingsRow>
+        <SettingsRow icon={Thermometer} title={t("settings.units.temperature.title")} description={t("settings.units.temperature.description")}>
+          <div className="surface-control inline-flex rounded-full p-1" role="radiogroup" aria-label={t("settings.units.temperature.label")}>
+            {TEMPERATURE_UNITS.map((unit) => (
+              <button
+                key={unit}
+                type="button"
+                role="radio"
+                aria-checked={temperatureUnit === unit}
+                className={`min-w-14 rounded-full border px-3.5 py-1.5 text-sm font-medium transition-colors focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-accent ${
+                  temperatureUnit === unit
+                    ? "border-accent/45 bg-accent/10 text-accent shadow-soft"
+                    : "border-transparent text-muted hover:bg-surface-muted/70 hover:text-foreground"
+                }`}
+                onClick={() => setTemperatureUnit(unit)}
+              >
+                {t(temperatureUnitKeys[unit])}
+              </button>
+            ))}
+          </div>
+        </SettingsRow>
        <SettingsRow icon={Wind} title={t("settings.units.wind.title")} description={t("settings.units.wind.description")}>
          <div className="surface-control inline-flex rounded-full p-1" role="radiogroup" aria-label={t("settings.units.wind.label")}>
            {WIND_SPEED_UNITS.map((unit) => (
--- a/components/weather/current-conditions-card.tsx
+++ b/components/weather/current-conditions-card.tsx
@@ -9,16 +9,17 @@ import { useWeatherStore } from "@/lib/store";

 export function CurrentConditionsCard({ station }: { station: SynopStation }) {
  const { language, t } = useI18n();
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const windSpeedUnit = useWeatherStore((state) => state.windSpeedUnit);
  const feelsLike = calculateFeelsLike(station.temperature, station.humidity, station.windSpeed);
  const metrics = [
-    { icon: Thermometer, label: t("weather.feelsLike"), value: formatTemperature(feelsLike, language), detail: t("weather.feelsLikeDetail") },
+    { icon: Thermometer, label: t("weather.feelsLike"), value: formatTemperature(feelsLike, language, temperatureUnit), detail: t("weather.feelsLikeDetail") },
    { icon: Droplets, label: t("weather.humidity"), value: formatHumidity(station.humidity, language), detail: t("weather.humidityDetail") },
    { icon: Gauge, label: t("weather.pressure"), value: formatPressure(station.pressure, language), detail: t("weather.pressureDetail") },
    { icon: Wind, label: t("weather.windSpeed"), value: formatWind(station.windSpeed, null, language, windSpeedUnit), detail: t("weather.windSpeedDetail") },
    { icon: Navigation, label: t("weather.windDirection"), value: station.windDirection === null ? t("common.noData") : `${station.windDirection}° ${getWindDirection(station.windDirection)}`, detail: t("weather.windDirectionDetail") },
    { icon: Umbrella, label: t("weather.rainfallTotal"), value: formatRainfall(station.rainfall, language), detail: t("weather.rainfallDetail") },
-    { icon: CloudSun, label: t("weather.airTemperature"), value: formatTemperature(station.temperature, language), detail: t("weather.temperatureDetail") },
+    { icon: CloudSun, label: t("weather.airTemperature"), value: formatTemperature(station.temperature, language, temperatureUnit), detail: t("weather.temperatureDetail") },
  ];
  return (
    <div className="grid gap-3 sm:grid-cols-2 lg:grid-cols-4">
--- a/components/weather/featured-stations-section.tsx
+++ b/components/weather/featured-stations-section.tsx
@@ -14,6 +14,7 @@ export function FeaturedStationsSection({ stations }: { stations: SynopStation[]
  const { language, t } = useI18n();
  const selectedStationId = useWeatherStore((state) => state.selectedStationId);
  const selectStation = useWeatherStore((state) => state.selectStation);
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const featured = featuredNames.flatMap((name) => stations.find((station) => station.name === name) ?? []);
  return (
    <section className="space-y-3">
@@ -33,7 +34,7 @@ export function FeaturedStationsSection({ stations }: { stations: SynopStation[]
            >
              <span className="min-w-0">
                <span className="block truncate text-xs font-medium text-muted">{station.name}</span>
-                <span className="mt-1 block text-xl font-semibold tracking-tight">{formatTemperature(station.temperature, language)}</span>
+                <span className="mt-1 block text-xl font-semibold tracking-tight">{formatTemperature(station.temperature, language, temperatureUnit)}</span>
              </span>
              <WeatherIcon mood={getWeatherMoodFromData(station)} className="size-6 shrink-0 text-accent" />
            </button>
--- a/components/weather/station-card.tsx
+++ b/components/weather/station-card.tsx
@@ -17,6 +17,7 @@ export function StationCard({ station, index = 0 }: { station: SynopStation; ind
  const favorites = useWeatherStore((state) => state.favorites);
  const toggleFavorite = useWeatherStore((state) => state.toggleFavorite);
  const selectStation = useWeatherStore((state) => state.selectStation);
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const windSpeedUnit = useWeatherStore((state) => state.windSpeedUnit);
  const favorite = favorites.includes(station.id);
  const mood = getWeatherMoodFromData(station);
@@ -27,7 +28,7 @@ export function StationCard({ station, index = 0 }: { station: SynopStation; ind
        <div className="flex items-start justify-between gap-2">
          <Link href={`/station/${station.id}`} onClick={() => selectStation(station.id)} className="min-w-0 flex-1 rounded-lg focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent">
            <p className="truncate text-sm font-semibold">{station.name}</p>
-            <p className="mt-3 text-4xl font-light tracking-[-0.08em]">{formatTemperature(station.temperature, language)}</p>
+            <p className="mt-3 text-4xl font-light tracking-[-0.08em]">{formatTemperature(station.temperature, language, temperatureUnit)}</p>
          </Link>
          <div className="flex flex-col items-end gap-2">
            <WeatherIcon mood={mood} className="size-9 text-accent" />
--- a/components/weather/weather-hero.tsx
+++ b/components/weather/weather-hero.tsx
@@ -44,6 +44,7 @@ function readDevWeatherEffectOverride(): DevWeatherEffectOverride | null {

 export function WeatherHero({ station, currentWeather, currentWeatherLoading = false, locationName, distanceKm }: { station: SynopStation; currentWeather?: ImgwCurrentWeather | null; currentWeatherLoading?: boolean; locationName?: string; distanceKm?: number }) {
  const { language, t } = useI18n();
+  const temperatureUnit = useWeatherStore((state) => state.temperatureUnit);
  const windSpeedUnit = useWeatherStore((state) => state.windSpeedUnit);
  const [devEffectOverride, setDevEffectOverride] = useState<DevWeatherEffectOverride | null>(null);
  const displayedLocationName = locationName ?? station.name;
@@ -121,10 +122,10 @@ export function WeatherHero({ station, currentWeather, currentWeatherLoading = f
        <div className="mt-8 flex items-end justify-between gap-3 sm:mt-10">
          <div>
            <div className="text-[5.8rem] font-semibold leading-[0.85] tracking-[-0.1em] sm:text-[8rem]">
-              {formatTemperature(displayedStation.temperature, language)}
+              {formatTemperature(displayedStation.temperature, language, temperatureUnit)}
            </div>
            <p className="mt-5 text-xl font-medium tracking-tight sm:text-2xl">{getWeatherDescription(displayedStation, language, currentWeather?.condition)}</p>
-            <p className="mt-1 text-sm text-muted">{t("weather.feelsLike")} {formatTemperature(feelsLike, language)} · {t("weather.measurement")} {formatDateTime(displayedStation.measuredAt, language)}</p>
+            <p className="mt-1 text-sm text-muted">{t("weather.feelsLike")} {formatTemperature(feelsLike, language, temperatureUnit)} · {t("weather.measurement")} {formatDateTime(displayedStation.measuredAt, language)}</p>
          </div>
          <WeatherIcon mood={mood} condition={currentWeather?.condition} className="mb-4 size-20 text-accent sm:size-28" />
        </div>
--- a/docs/notifications.md
+++ b/docs/notifications.md
@@ -43,6 +43,7 @@ Subskrypcja Web Push zapisuje:
 - czy aktywny jest brief na jutro,
 - współrzędne i nazwę lokalizacji,
 - opcjonalny powiat TERYT,
+- wybraną jednostkę temperatury dla briefów wysyłanych z serwera,
 - wybraną jednostkę wiatru dla briefów wysyłanych z serwera.

 Ostrzeżenia meteo są filtrowane po powiecie TERYT, jeśli lokalizacja go dostarcza. W przeciwnym razie używany jest fallback wojewódzki.
--- a/docs/weather-logic.md
+++ b/docs/weather-logic.md
@@ -79,7 +79,7 @@ Prognoza godzinowa i dzienna rozpoznaje:

 Bieżąca analiza IMGW Hybrid rozpoznaje bezpośrednio opad deszczu, śnieg i burzę. Gdy żadne z tych zjawisk nie występuje, hero może pokazać pomocniczy opis: `Silny wiatr`, `Wilgotne warunki` albo `Spokojne warunki`.

-Jednostka wiatru wybierana w `/settings` dotyczy prezentacji w UI, briefach i powiadomieniach. Dane źródłowe oraz progi logiki pogody pozostają liczone w `m/s`.
+Jednostki temperatury i wiatru wybierane w `/settings` dotyczą prezentacji w UI, briefach i powiadomieniach. Dane źródłowe oraz progi logiki pogody pozostają liczone w `°C` i `m/s`.

 ## Mood i Efekty Wizualne

--- a/lib/forecast-utils.ts
+++ b/lib/forecast-utils.ts
@@ -1,8 +1,8 @@
 import type { Language, TranslationKey } from "@/lib/i18n";
 import { translate } from "@/lib/i18n";
-import { DEFAULT_WIND_SPEED_UNIT, formatWindSpeed } from "@/lib/weather-utils";
-import type { HourlyForecast } from "@/types/forecast";
-import type { WindSpeedUnit } from "@/types/units";
+import { DEFAULT_TEMPERATURE_UNIT, DEFAULT_WIND_SPEED_UNIT, formatTemperature, formatWindSpeed } from "@/lib/weather-utils";
+import type { DailyForecast, HourlyForecast } from "@/types/forecast";
+import type { TemperatureUnit, WindSpeedUnit } from "@/types/units";

 export function getForecastConditionKey(code: number | null): TranslationKey {
  if (code === 0) return "forecast.condition.clear";
@@ -20,9 +20,9 @@ export function getForecastCondition(code: number | null, language: Language) {
  return translate(language, getForecastConditionKey(code));
 }

-export function formatForecastTemperature(value: number | null, language: Language) {
+export function formatForecastTemperature(value: number | null, language: Language, unit: TemperatureUnit = DEFAULT_TEMPERATURE_UNIT) {
  if (value === null) return "—";
-  return `${new Intl.NumberFormat(language === "pl" ? "pl-PL" : "en-GB", { maximumFractionDigits: 0 }).format(value)}°`;
+  return formatTemperature(value, language, unit);
 }

 export function formatForecastRainfall(value: number | null, language: Language) {
@@ -89,6 +89,23 @@ export function getHourlyForecastForDay(hours: HourlyForecast[], date: string) {
  return hours.filter((hour) => hour.time.startsWith(`${date}T`));
 }

+export function getDailyForecastForHour(days: DailyForecast[], time: string) {
+  return days.find((day) => time.startsWith(`${day.date}T`)) ?? null;
+}
+
+export function isForecastNight(time: string, day: Pick<DailyForecast, "sunrise" | "sunset"> | null | undefined) {
+  const hourTimestamp = parseForecastHour(time);
+  const sunriseTimestamp = day?.sunrise ? parseForecastHour(day.sunrise) : null;
+  const sunsetTimestamp = day?.sunset ? parseForecastHour(day.sunset) : null;
+
+  if (hourTimestamp !== null && sunriseTimestamp !== null && sunsetTimestamp !== null) {
+    return hourTimestamp < sunriseTimestamp || hourTimestamp >= sunsetTimestamp;
+  }
+
+  const hour = getForecastHourOfDay(time);
+  return hour !== null && (hour < 6 || hour >= 21);
+}
+
 export function isForecastHourPast(time: string) {
  const currentHour = getWarsawForecastHour();
  const hourTimestamp = parseForecastHour(time);
--- a/lib/i18n.tsx
+++ b/lib/i18n.tsx
@@ -26,6 +26,11 @@ const translations = {
    "settings.language.description": "Zmieniaj język interfejsu. Nazwy stacji i treści IMGW pozostają bez automatycznego tłumaczenia.",
    "settings.theme.title": "Motyw",
    "settings.theme.description": "Przełącz jasny lub ciemny wygląd aplikacji na tym urządzeniu.",
+    "settings.units.temperature.title": "Jednostka temperatury",
+    "settings.units.temperature.description": "Stosowana w prognozie, briefach, powiadomieniach i bieżących pomiarach na tym urządzeniu.",
+    "settings.units.temperature.label": "Wybierz jednostkę temperatury",
+    "settings.units.temperature.c": "°C",
+    "settings.units.temperature.f": "°F",
    "settings.units.wind.title": "Jednostka wiatru",
    "settings.units.wind.description": "Stosowana w prognozie, briefach, powiadomieniach i bieżących pomiarach na tym urządzeniu.",
    "settings.units.wind.label": "Wybierz jednostkę wiatru",
@@ -268,6 +273,11 @@ const translations = {
    "settings.language.description": "Change the interface language. Station names and IMGW content are not translated automatically.",
    "settings.theme.title": "Theme",
    "settings.theme.description": "Switch the light or dark appearance on this device.",
+    "settings.units.temperature.title": "Temperature unit",
+    "settings.units.temperature.description": "Used in forecasts, briefs, notifications and current readings on this device.",
+    "settings.units.temperature.label": "Choose temperature unit",
+    "settings.units.temperature.c": "°C",
+    "settings.units.temperature.f": "°F",
    "settings.units.wind.title": "Wind unit",
    "settings.units.wind.description": "Used in forecasts, briefs, notifications and current readings on this device.",
    "settings.units.wind.label": "Choose wind unit",
--- a/lib/notification-api.ts
+++ b/lib/notification-api.ts
@@ -1,6 +1,6 @@
 import type { Language } from "@/lib/i18n";
 import type { Province } from "@/types/province";
-import type { WindSpeedUnit } from "@/types/units";
+import type { TemperatureUnit, WindSpeedUnit } from "@/types/units";

 interface VapidKeyResponse {
  configured: boolean;
@@ -20,6 +20,7 @@ interface SavePushSubscriptionOptions {
  longitude?: number | null;
  locationName?: string | null;
  countyTeryt?: string | null;
+  temperatureUnit?: TemperatureUnit;
  windSpeedUnit?: WindSpeedUnit;
 }

@@ -38,6 +39,7 @@ export async function savePushSubscription(subscription: PushSubscription, provi
      longitude: options.longitude ?? null,
      locationName: options.locationName ?? null,
      countyTeryt: options.countyTeryt ?? null,
+      temperatureUnit: options.temperatureUnit,
      windSpeedUnit: options.windSpeedUnit,
    }),
  });
--- a/lib/store.ts
+++ b/lib/store.ts
@@ -4,8 +4,8 @@ import { create } from "zustand";
 import { persist } from "zustand/middleware";
 import type { SelectedLocation } from "@/types/location";
 import type { Province } from "@/types/province";
-import type { WindSpeedUnit } from "@/types/units";
-import { DEFAULT_WIND_SPEED_UNIT } from "@/lib/weather-utils";
+import type { TemperatureUnit, WindSpeedUnit } from "@/types/units";
+import { DEFAULT_TEMPERATURE_UNIT, DEFAULT_WIND_SPEED_UNIT } from "@/lib/weather-utils";

 type NotificationProvinceMode = "selected" | "manual";

@@ -18,6 +18,7 @@ interface WeatherStore {
  tomorrowBriefNotificationsEnabled: boolean;
  warningNotificationProvinceMode: NotificationProvinceMode;
  warningNotificationProvince: Province | null;
+  temperatureUnit: TemperatureUnit;
  windSpeedUnit: WindSpeedUnit;
  toggleFavorite: (id: string) => void;
  selectStation: (id: string) => void;
@@ -27,6 +28,7 @@ interface WeatherStore {
  setTomorrowBriefNotificationsEnabled: (enabled: boolean) => void;
  setWarningNotificationProvinceMode: (mode: NotificationProvinceMode) => void;
  setWarningNotificationProvince: (province: Province | null) => void;
+  setTemperatureUnit: (unit: TemperatureUnit) => void;
  setWindSpeedUnit: (unit: WindSpeedUnit) => void;
 }

@@ -41,6 +43,7 @@ export const useWeatherStore = create<WeatherStore>()(
      tomorrowBriefNotificationsEnabled: false,
      warningNotificationProvinceMode: "selected",
      warningNotificationProvince: null,
+      temperatureUnit: DEFAULT_TEMPERATURE_UNIT,
      windSpeedUnit: DEFAULT_WIND_SPEED_UNIT,
      toggleFavorite: (id) =>
        set((state) => ({
@@ -55,6 +58,7 @@ export const useWeatherStore = create<WeatherStore>()(
      setTomorrowBriefNotificationsEnabled: (enabled) => set({ tomorrowBriefNotificationsEnabled: enabled }),
      setWarningNotificationProvinceMode: (mode) => set({ warningNotificationProvinceMode: mode }),
      setWarningNotificationProvince: (province) => set({ warningNotificationProvince: province }),
+      setTemperatureUnit: (unit) => set({ temperatureUnit: unit }),
      setWindSpeedUnit: (unit) => set({ windSpeedUnit: unit }),
    }),
    { name: "wtr:preferences" },
--- a/lib/weather-brief.ts
+++ b/lib/weather-brief.ts
@@ -5,8 +5,8 @@ import type { HourlyForecast, WeatherForecast } from "@/types/forecast";
 import type { WeatherWarning } from "@/types/imgw";
 import type { Province } from "@/types/province";
 import { warningMatchesCounty } from "@/lib/warning-regions";
-import { DEFAULT_WIND_SPEED_UNIT, formatWindSpeed } from "@/lib/weather-utils";
-import type { WindSpeedUnit } from "@/types/units";
+import { DEFAULT_TEMPERATURE_UNIT, DEFAULT_WIND_SPEED_UNIT, formatTemperature as formatDisplayTemperature, formatWindSpeed } from "@/lib/weather-utils";
+import type { TemperatureUnit, WindSpeedUnit } from "@/types/units";

 export type WeatherBriefSeverity = "normal" | "attention" | "warning";

@@ -26,6 +26,7 @@ interface BuildWeatherBriefInput {
  countyTeryt?: string | null;
  locationName: string;
  language: Language;
+  temperatureUnit?: TemperatureUnit;
  windSpeedUnit?: WindSpeedUnit;
  now?: Date;
 }
@@ -36,10 +37,6 @@ function formatNumber(value: number, language: Language, digits = 0) {
  }).format(value);
 }

-function formatTemperature(value: number, language: Language) {
-  return `${formatNumber(value, language)}°C`;
-}
-
 function formatRainfall(value: number, language: Language) {
  return `${formatNumber(value, language, 1)} mm`;
 }
@@ -202,7 +199,7 @@ function getTomorrowCondition(hours: HourlyForecast[], rainfallTotal: number | n
  return language === "pl" ? "bez istotnych opadów" : "no significant precipitation";
 }

-export function buildWeatherBrief({ forecast, warnings, province, countyTeryt, locationName, language, windSpeedUnit = DEFAULT_WIND_SPEED_UNIT, now = new Date() }: BuildWeatherBriefInput): WeatherBrief | null {
+export function buildWeatherBrief({ forecast, warnings, province, countyTeryt, locationName, language, temperatureUnit = DEFAULT_TEMPERATURE_UNIT, windSpeedUnit = DEFAULT_WIND_SPEED_UNIT, now = new Date() }: BuildWeatherBriefInput): WeatherBrief | null {
  const hours = getUpcomingHours(forecast.hourly, now, 24);
  if (!hours.length) return null;

@@ -218,7 +215,7 @@ export function buildWeatherBrief({ forecast, warnings, province, countyTeryt, l
  const rainPeakHour = getPeakHour(hours, (hour) => hour.precipitationProbability);
  const conditionPeakHour = hours.find((hour) => hour.weatherCode !== null) ?? null;
  const temperatureRange = minimumTemperature !== null && maximumTemperature !== null
-    ? `${formatTemperature(minimumTemperature, language)}-${formatTemperature(maximumTemperature, language)}`
+    ? `${formatDisplayTemperature(minimumTemperature, language, temperatureUnit)}-${formatDisplayTemperature(maximumTemperature, language, temperatureUnit)}`
    : null;
  const hasRainSignal = (maximumProbability ?? 0) >= 35 || (rainfallTotal ?? 0) >= 0.5;
  const hasWindSignal = (maximumWind ?? 0) >= 8;
@@ -295,7 +292,7 @@ export function buildWeatherBrief({ forecast, warnings, province, countyTeryt, l
  };
 }

-export function buildTomorrowWeatherBrief({ forecast, warnings, province, countyTeryt, locationName, language, windSpeedUnit = DEFAULT_WIND_SPEED_UNIT, now = new Date() }: BuildWeatherBriefInput): WeatherBrief | null {
+export function buildTomorrowWeatherBrief({ forecast, warnings, province, countyTeryt, locationName, language, temperatureUnit = DEFAULT_TEMPERATURE_UNIT, windSpeedUnit = DEFAULT_WIND_SPEED_UNIT, now = new Date() }: BuildWeatherBriefInput): WeatherBrief | null {
  const targetDateKey = getWarsawDateKey(now, 1);
  const hours = getForecastHoursForDate(forecast.hourly, targetDateKey);
  if (!hours.length) return null;
@@ -318,7 +315,7 @@ export function buildTomorrowWeatherBrief({ forecast, warnings, province, county
  const hasWindSignal = (maximumWind ?? 0) >= 8;
  const condition = getTomorrowCondition(hours, rainfallTotal, maximumProbability, language);
  const temperatureRange = minimumTemperature !== null && maximumTemperature !== null
-    ? `${formatTemperature(minimumTemperature, language)} / ${formatTemperature(maximumTemperature, language)}`
+    ? `${formatDisplayTemperature(minimumTemperature, language, temperatureUnit)} / ${formatDisplayTemperature(maximumTemperature, language, temperatureUnit)}`
    : null;
  const severity: WeatherBriefSeverity = topWarning || hasThunderstorm ? "warning" : hasRainSignal || hasWindSignal ? "attention" : "normal";
  const provinceLabel = province ? formatProvinceName(province, language) : null;
--- a/lib/weather-utils.ts
+++ b/lib/weather-utils.ts
@@ -11,12 +11,19 @@ import type {
 import { translate, type Language } from "@/lib/i18n";
 import { getProvinceFromTeryt, normalizeProvinceName } from "@/lib/provinces";
 import type { CurrentWeatherCondition } from "@/types/imgw-current";
-import type { WindSpeedUnit } from "@/types/units";
+import type { TemperatureUnit, WindSpeedUnit } from "@/types/units";

 const locales: Record<Language, string> = { pl: "pl-PL", en: "en-GB" };
-export const DEFAULT_WIND_SPEED_UNIT: WindSpeedUnit = "ms";
+export const DEFAULT_TEMPERATURE_UNIT: TemperatureUnit = "c";
+export const TEMPERATURE_UNITS: TemperatureUnit[] = ["c", "f"];
+export const DEFAULT_WIND_SPEED_UNIT: WindSpeedUnit = "kmh";
 export const WIND_SPEED_UNITS: WindSpeedUnit[] = ["ms", "kmh", "mph"];

+const temperatureUnitLabels: Record<TemperatureUnit, string> = {
+  c: "°C",
+  f: "°F",
+};
+
 const windSpeedUnitLabels: Record<WindSpeedUnit, string> = {
  ms: "m/s",
  kmh: "km/h",
@@ -105,8 +112,28 @@ export function normalizeWarning(raw: RawWarning, kind: WarningKind, index: numb
  };
 }

-export function formatTemperature(value: number | null, language: Language = "pl") {
-  return value === null ? translate(language, "common.noData") : `${Math.round(value)}°`;
+export function isTemperatureUnit(value: unknown): value is TemperatureUnit {
+  return typeof value === "string" && TEMPERATURE_UNITS.includes(value as TemperatureUnit);
+}
+
+export function getTemperatureUnitLabel(unit: TemperatureUnit) {
+  return temperatureUnitLabels[unit];
+}
+
+export function convertTemperature(value: number, unit: TemperatureUnit) {
+  if (unit === "f") return (value * 9) / 5 + 32;
+  return value;
+}
+
+export function formatTemperatureValue(value: number, language: Language = "pl", unit: TemperatureUnit = DEFAULT_TEMPERATURE_UNIT) {
+  const formattedValue = new Intl.NumberFormat(locales[language], {
+    maximumFractionDigits: 0,
+  }).format(value);
+  return `${formattedValue}${getTemperatureUnitLabel(unit)}`;
+}
+
+export function formatTemperature(value: number | null, language: Language = "pl", unit: TemperatureUnit = DEFAULT_TEMPERATURE_UNIT) {
+  return value === null ? translate(language, "common.noData") : formatTemperatureValue(convertTemperature(value, unit), language, unit);
 }

 export function formatPressure(value: number | null, language: Language = "pl") {
--- a/types/notifications.ts
+++ b/types/notifications.ts
@@ -1,6 +1,6 @@
 import type { Language } from "@/lib/i18n";
 import type { Province } from "@/types/province";
-import type { WindSpeedUnit } from "@/types/units";
+import type { TemperatureUnit, WindSpeedUnit } from "@/types/units";

 export interface PushSubscriptionKeys {
  p256dh: string;
@@ -25,6 +25,7 @@ export interface WarningPushSubscription {
  longitude: number | null;
  locationName: string | null;
  countyTeryt: string | null;
+  temperatureUnit: TemperatureUnit;
  windSpeedUnit: WindSpeedUnit;
  createdAt: string;
  updatedAt: string;
--- a/types/units.ts
+++ b/types/units.ts
@@ -1 +1,2 @@
+export type TemperatureUnit = "c" | "f";
 export type WindSpeedUnit = "ms" | "kmh" | "mph";
Author	SHA1	Message	Date
zv	5a8e39dbe2	fix: show night icons for hourly forecast All checks were successful CI / Lint, typecheck and build (push) Successful in 10m2s Details	2026-06-13 21:27:41 +02:00
zv	83c0657296	fix: default wind unit to kmh	2026-06-13 21:21:52 +02:00
zv	cb113714f9	feat: add temperature unit preference	2026-06-13 21:05:01 +02:00