feat(weather): 6-day forecast

FORECAST_DAYS=6 in lib/weather.ts is the single source for the fetch length and the UI labels (spot card + map popup). New count-interpolated labels spotUi.forecastDays / mapUi.forecastDays (en/es; other locales fall back to English). Legend colours moved to lib/skateabilityLevels.ts to keep the react-refresh lint at zero.

AGENTS.md

@@ -2411,7 +2411,11 @@ composed in `legacy/index.ts` and spread into `en`/`es` (same pattern as
   weather card, **sunrise/sunset** (`weather.ts` fetches Open-Meteo daily
   `sunrise,sunset`), and the score's reasons now render as **chips** instead of a
   bullet-joined run-on. Popup `text-gray-500` → `gray-300` for contrast. Units stay
-  **Celsius / km/h** (deliberate — no unit toggle).
+  **Celsius / km/h** (deliberate — no unit toggle). The forecast is now **6 days**
+  (`FORECAST_DAYS` in `lib/weather.ts` is the single source for the fetch and the
+  labels; the legend colours live in `lib/skateabilityLevels.ts`). Labels use
+  `spotUi.forecastDays` / `mapUi.forecastDays` with a `{{count}}` param (the other
+  locales fall back to English until translated).
 - `skaterLabelsUi` (21) — skater stance/style/level + sponsor tiers in `types.ts`
 - `notifyUi` (28) — OS notification titles/bodies (`OsNotificationBridge`)
 - `legacyMiscUi` (~160) — scattered component/page literals, image `alt`/`aria-label`,

src/components/SpotMap.tsx

@@ -12,6 +12,7 @@ import type { BtcMapPlace } from '@/hooks/useBtcMapPlaces';
 import { isRecentlyVerified, isBoosted } from '@/hooks/useBtcMapPlaces';
 import { sanitizeUrl } from '@/lib/sanitizeUrl';
 import { createCachedTileLayer } from '@/lib/cachedTileLayer';
+import { FORECAST_DAYS } from '@/lib/weather';
 import { useTranslation } from '@/contexts/language';
 
 /** Translation function shape, so module-level popup builders can receive `t`. */
@@ -627,7 +628,7 @@ function createPopupContent(
 
       const forecastTitle = document.createElement('div');
       forecastTitle.className = 'text-xs font-semibold mb-1 text-gray-700';
-      forecastTitle.textContent = t('mapUi.threeDayForecast');
+      forecastTitle.textContent = t('mapUi.forecastDays', { count: FORECAST_DAYS });
       forecastDiv.appendChild(forecastTitle);
 
       const forecastGrid = document.createElement('div');

src/components/WeatherLegend.tsx

@@ -1,17 +1,5 @@
 import { useTranslation } from '@/contexts/language';
-
-/**
- * The skateability colour scale, mirroring `calculateSkateability` in lib/weather.
- * Kept here (not derived at runtime) so the legend and the scorer can't drift
- * silently — if the thresholds change there, change them here too.
- */
-export const SKATEABILITY_LEVELS: { key: string; color: string }[] = [
-  { key: 'weatherUi.skateability.perfect', color: '#00e400' },
-  { key: 'weatherUi.skateability.good', color: '#92d050' },
-  { key: 'weatherUi.skateability.okay', color: '#ffff00' },
-  { key: 'weatherUi.skateability.poor', color: '#ff7e00' },
-  { key: 'weatherUi.skateability.bad', color: '#ff0000' },
-];
+import { SKATEABILITY_LEVELS } from '@/lib/skateabilityLevels';
 
 /**
  * Small map overlay explaining the weather-layer marker colours. Rendered by

src/i18n/en.ts

@@ -934,6 +934,7 @@ mapUi: {
     humidity: 'Humidity',
     airQuality: 'Air quality',
     threeDayForecast: '3-Day Forecast',
+    forecastDays: '{{count}}-Day Forecast',
     gearForSale: 'Gear for sale ({{count}})',
     viewItems: 'View Items →',
     viewAllItems: 'View All {{count}} Items →',
@@ -1366,6 +1367,7 @@ spotUi: {
     tagsSuggestedDesc: 'Your tag suggestions have been submitted.',
     takePhoto: 'Take Photo',
     threeDayForecast: '3-Day Forecast',
+    forecastDays: '{{count}}-Day Forecast',
     tipTheMapper: 'Tip the Mapper',
     tipTheMapperDesc: 'Found this spot useful? Send a zap to thank the mapper!',
     titleRequired: 'Title required',

src/i18n/es.ts

@@ -934,6 +934,7 @@ mapUi: {
     humidity: 'Humedad',
     airQuality: 'Calidad del aire',
     threeDayForecast: 'Previsión a 3 días',
+    forecastDays: 'Pronóstico de {{count}} días',
     gearForSale: 'Equipo en venta ({{count}})',
     viewItems: 'Ver artículos →',
     viewAllItems: 'Ver los {{count}} artículos →',
@@ -1366,6 +1367,7 @@ spotUi: {
     tagsSuggestedDesc: 'Tus sugerencias de etiquetas se han enviado.',
     takePhoto: 'Hacer foto',
     threeDayForecast: 'Previsión a 3 días',
+    forecastDays: 'Pronóstico de {{count}} días',
     tipTheMapper: 'Invita al autor',
     tipTheMapperDesc: '¿Te ha servido este spot? ¡Envía un zap para agradecer al autor!',
     titleRequired: 'Título obligatorio',

src/lib/skateabilityLevels.ts

@@ -0,0 +1,15 @@
+/**
+ * The skateability colour scale, shown in the map's weather legend.
+ *
+ * Kept as a plain module (not exported from a component file — that trips the
+ * `react-refresh` lint rule) and mirrors the colours emitted by
+ * `calculateSkateability` in `lib/weather.ts`. If a threshold there changes,
+ * change it here too.
+ */
+export const SKATEABILITY_LEVELS: { key: string; color: string }[] = [
+  { key: 'weatherUi.skateability.perfect', color: '#00e400' },
+  { key: 'weatherUi.skateability.good', color: '#92d050' },
+  { key: 'weatherUi.skateability.okay', color: '#ffff00' },
+  { key: 'weatherUi.skateability.poor', color: '#ff7e00' },
+  { key: 'weatherUi.skateability.bad', color: '#ff0000' },
+];

src/lib/weather.ts

@@ -190,8 +190,11 @@ export async function fetchAirQuality(lat: number, lng: number): Promise<AirQual
   };
 }
 
+/** Forecast length requested and displayed (Open-Meteo supports up to 16 days). */
+export const FORECAST_DAYS = 6;
+
 /**
- * Fetch 3-day weather forecast for a location
+ * Fetch a multi-day weather forecast for a location
  */
 export async function fetchWeatherForecast(lat: number, lng: number): Promise<WeatherForecast> {
   const params = new URLSearchParams({
@@ -200,7 +203,7 @@ export async function fetchWeatherForecast(lat: number, lng: number): Promise<We
     daily: 'weather_code,temperature_2m_max,temperature_2m_min,precipitation_probability_max,sunrise,sunset',
     temperature_unit: 'celsius',
     timezone: 'auto',
-    forecast_days: '3',
+    forecast_days: String(FORECAST_DAYS),
   });
 
   const response = await fetch(`https://api.open-meteo.com/v1/forecast?${params}`);

src/pages/SpotDetailPage.tsx

@@ -1,4 +1,5 @@
 import { dateLocaleCode, formatDistanceToNow } from '@/lib/dateFnsI18n';
+import { FORECAST_DAYS } from '@/lib/weather';
 import { labProfilePath } from '@/lib/labRoutes';
 import { useMemo, useState } from 'react';
 import { useSeoMeta } from '@unhead/react';
@@ -1142,7 +1143,7 @@ export default function SpotDetailPage() {
                   {/* 3-Day Forecast */}
                   {weatherData.forecast?.daily && weatherData.forecast.daily.length > 0 && (
                     <div className="pt-3 border-t border-border">
-                      <div className="text-sm font-semibold mb-3">{t('spotUi.threeDayForecast')}</div>
+                      <div className="text-sm font-semibold mb-3">{t('spotUi.forecastDays', { count: FORECAST_DAYS })}</div>
                       <div className="grid grid-cols-3 gap-2">
                         {weatherData.forecast.daily.map((day, idx) => {
                           const date = new Date(day.date);