diff --git a/app.py b/app.py
index c720438..3e1bb81 100644
--- a/app.py
+++ b/app.py
@@ -545,7 +545,13 @@ def get_mosmix_forecast(lat, lon, hours=72):
             rprob    = p.get("probability_precipitation_height_gt_0_1mm_last_1h")
             rain_prob = round(float(rprob)*100) if not _isnan(rprob) else None
             n        = p.get("cloud_cover_total")
-            clouds   = round(float(n)*100) if not _isnan(n) else None
+            if not _isnan(n):
+                nf = float(n)
+                # wetterdienst returns cloud cover as a 0-1 fraction (like probabilities);
+                # guard against stations that already return 0-100 percent.
+                clouds = _clamp(round(nf * 100 if nf <= 1.0 else nf), 0, 100)
+            else:
+                clouds = None
             sun      = p.get("sunshine_duration")
             sun_min  = round(float(sun)/60) if not _isnan(sun) else 0
             wd       = p.get("wind_direction")