diff --git a/backend/src/lib/weather.js b/backend/src/lib/weather.js
index f9aba68..0472939 100644
--- a/backend/src/lib/weather.js
+++ b/backend/src/lib/weather.js
@@ -7,10 +7,18 @@
 //
 // Provider selection: Met Office DataHub if an api_key is configured AND the
 // integration is enabled in settings (the existing enable/disable toggle IS the
-// "use Met Office" switch); otherwise Open-Meteo, which needs no key at all. Either
-// way this only ever returns TODAY's forecast high — not live/current temperature —
-// so a tier, once picked at an occupied-state transition, doesn't need to fight
-// hour-to-hour swings (see scheduler.js's applyStateTransition()).
+// "use Met Office" switch); otherwise, OR if the Met Office call fails for any reason
+// (see the catch below), Open-Meteo — which needs no key at all. Either way this only
+// ever returns TODAY's forecast high — not live/current temperature — so a tier, once
+// picked at an occupied-state transition, doesn't need to fight hour-to-hour swings
+// (see scheduler.js's applyStateTransition()).
+//
+// IMPORTANT: fetchFromMetOffice() below calls the "Global Spot" deterministic product
+// (`sitespecific/v0/point/daily`) — a DIFFERENT Met Office DataHub subscription from
+// the "Site-Specific Blended Probabilistic Forecast" product (percentile/probability
+// bands, no plain max-temp field). Subscribing to the wrong one on the DataHub side
+// gives a 403 here, which the catch below quietly degrades to Open-Meteo — confirmed
+// live 2026-08-25.
 const CACHE_TTL_MS = 60 * 60 * 1000        // 1h — forecasts don't move fast enough to poll more often
 const STALE_FALLBACK_MS = 6 * 60 * 60 * 1000 // still serve a cached value up to 6h old if a refetch fails
 
@@ -73,9 +81,22 @@ export async function getPeakTempC() {
     }
 
     const metOffice = await getIntegration('met_office')
-    const peakC = metOffice?.api_key
-      ? await fetchFromMetOffice(lat, lon, metOffice.api_key)
-      : await fetchFromOpenMeteo(lat, lon)
+    let peakC
+    if (metOffice?.api_key) {
+      try {
+        peakC = await fetchFromMetOffice(lat, lon, metOffice.api_key)
+      } catch (err) {
+        // Met Office configured but the call failed (wrong product subscription, key not
+        // yet propagated, outage, ...) — degrade to Open-Meteo rather than going dark.
+        // Common cause: the key is only subscribed to the Site-Specific Blended
+        // Probabilistic Forecast product, not the deterministic Global Spot one this
+        // fetches from — they're separate subscriptions on Met Office's side.
+        console.error('[weather] Met Office fetch failed, falling back to Open-Meteo:', err.message)
+        peakC = await fetchFromOpenMeteo(lat, lon)
+      }
+    } else {
+      peakC = await fetchFromOpenMeteo(lat, lon)
+    }
 
     cache = { peakC, fetchedAt: Date.now() }
     return peakC