Made forecast-period conditionCode optional

internal/normalizers/openmeteo/forecast.go

@@ -98,6 +98,7 @@ func buildForecast(parsed omForecastResponse, fallbackIssued time.Time) (model.W
 		}
 
 		wmo := wmoAt(parsed.Hourly.WeatherCode, i)
+		wmoPtr := wmoCodePtr(wmo)
 		canonicalText := standards.WMOText(wmo, isDay)
 
 		period := model.WeatherForecastPeriod{
@@ -107,7 +108,7 @@ func buildForecast(parsed omForecastResponse, fallbackIssued time.Time) (model.W
 			Name:  "",
 			IsDay: isDay,
 
-			ConditionCode:   wmo,
+			ConditionCode:   wmoPtr,
 			TextDescription: canonicalText,
 		}
 
@@ -237,3 +238,8 @@ func wmoAt(vals []*int, idx int) model.WMOCode {
 	}
 	return model.WMOUnknown
 }
+
+func wmoCodePtr(code model.WMOCode) *model.WMOCode {
+	out := code
+	return &out
+}

internal/normalizers/openmeteo/forecast_test.go

@@ -35,6 +35,9 @@ func TestBuildForecastUsesCanonicalTextDescription(t *testing.T) {
 	if got := run.Periods[0].TextDescription; got != expectedText {
 		t.Fatalf("TextDescription = %q, want %q", got, expectedText)
 	}
+	if run.Periods[0].ConditionCode == nil {
+		t.Fatalf("ConditionCode is nil, want mapped WMO code")
+	}
 
 	wantIssued := time.Date(2026, 3, 16, 19, 0, 0, 0, time.UTC)
 	if !run.IssuedAt.Equal(wantIssued) {