fix(wind): restore model rendering and show valid time

server/providers/wind/catalog.js

@@ -14,3 +14,16 @@ export function selectLatestGfsCycle(nowMs, { availabilityLagMs = 5 * 3600_000 }
   date.setUTCHours(hour);
   return { date: date.toISOString().slice(0, 10).replaceAll('-', ''), hour };
 }
+
+/**
+ * Round a time offset to the nearest published GFS forecast step so the field
+ * shown is the one valid closest to now, not always the analysis (f000).
+ * GFS 0.25° is hourly through f120, then every 3 h through f384.
+ * @param {number} hours - Hours elapsed since the cycle run time.
+ * @returns {number} A valid forecast step.
+ */
+export function nearestGfsStep(hours) {
+  const value = Math.max(0, Number.isFinite(hours) ? hours : 0);
+  const step = value <= 120 ? Math.round(value) : Math.round(value / 3) * 3;
+  return Math.max(0, Math.min(384, step));
+}