Atlantic High Brings Mild Early Autumn Weather Across Germany Following Cold Front

Atlantic high replaces cold front

A cold front crossing Germany has introduced cooler maritime air, reducing temperatures at the start of the week before an Atlantic high-pressure system restores drier conditions. High temperatures on Monday range between 13 and 20 degrees Celsius across wide areas, though sunlit stretches along the Rhine reach 21 to 23 degrees Celsius. The German Weather Service reported that the week leads into astronomical autumn on 23 September. Nighttime conditions indicate the changing season, with temperatures dropping to between 4 and 8 degrees Celsius in Bavaria and down to 5 degrees Celsius in low mountain ranges. Ground frost remains possible in parts of the south during early morning hours.

DWD meteorologist Martin Jonas in Offenbach described the current weather pattern as mild despite the cooler nights.

We are basically still doing quite well warmth-wise. However, one notices, particularly in the nights, that we are no longer in midsummer.

Regional conditions and low river levels

In Bavaria, Monday brings heavy cloud cover to Upper Franconia and the Upper Palatinate, while initial rain near the Alps clears as Swabia and Upper Bavaria experience more sunshine. High-altitude peaks in the Bavarian Forest and Berchtesgaden Alps face strong to gale-force wind gusts, accompanied by nighttime fog with visibility under 150 meters. The southwest enjoys the longest sunny intervals, with temperatures projected to rise up to 25 degrees Celsius in Breisgau by Wednesday. However, persistent dry weather creates complications for water bodies in the southern regions. Water levels on the Rhine and Lake Constance are nearing their lowest points, in contrast to the more stable water balance recorded in northern Germany.

Cloud shifts and late-week outlook

In North Rhine-Westphalia, the atmosphere stabilizes after weekend rain and wind, maintaining daily temperatures between 20 and 23 degrees Celsius alongside night lows of 6 degrees Celsius. Tuesday brings local drizzle across western regions, while Wednesday remains dry across the state before cloud cover increases again. DWD forecasts indicate that weather models show increased uncertainty beginning Thursday due to a small-scale low-pressure system. Dense cloud cover, showers, and isolated thunderstorms are expected to push into the northwest overnight from Wednesday into Thursday.

Jonas emphasized that the broader weather pattern remains relatively dry and settled for early autumn.

We are far from a wet, cold autumn.

Late-September temperature projections

Longer-range weather models indicate a potential surge in warmth toward the end of September. Calculations from the European Centre for Medium-Range Weather Forecasts project localized peak temperatures of around 31 degrees Celsius on 26 September. Swiss meteorologist Jörg Kachelmann noted the European model calculations, while meteorologist Dominik Jung from wetter.net projected rising temperatures focused primarily across southern Germany. In Germany, a heatwave is defined as at least three consecutive days with maximum temperatures reaching 30 degrees Celsius or higher. Forecast uncertainties increase for the final week of September, leaving it unsettled whether multiple regions will reach that official threshold.