On October 1, rain is expected to fall widely in Hamburg and Hanover under the influence of a low-pressure system, with thunderstorms and localized heavy rain possible in some areas.
In Braunschweig, the rain may become heavier in the late afternoon or in the early hours of October 2.
However, this does not mean that official severe-weather warnings have already been issued for a specific city or region.
3-line summary
1. Rain and thunderstorms possible in northern areas on October 1
2. The possibility of heavy rain totaling 20 liters per hour was also indicated
3. Possibilities and official warnings must be distinguished
Weather in Hamburg and Hanover Changes Dramatically Within a Day
The German Meteorological Service (DWD) forecast that, as a low-pressure system’s rainband moves into northern areas on October 1, rain would fall in Hamburg and Hanover, Bremen, Kiel, Oldenburg, Osnabrück, and other locations. It also mentioned the possibility that thunderstorms could accompany the rain in some areas and that locally heavy rain could pour down.
In particular, where thunderstorms occur, approximately 20 liters of rain could fall in one hour, according to the forecast. Regardless of thunderstorms, the possibility of 20~35 liters of heavy rain continuing over 6 hours was also presented, although it was considered low. This means that the intensity and timing of precipitation could vary greatly from one area to another.
Temperature changes are also pronounced. Hamburg reached 22~24 degrees in some areas the previous day, but its high temperature on October 1 was expected to be approximately 19~21 degrees. Hanover was likewise forecast to fall from approximately 27 degrees the previous day to approximately 21~22 degrees on October 1.
Rain Is Expected to Arrive Late in Braunschweig
In Braunschweig, Lower Saxony, the effects of the rain appear likely to intensify later than in other areas. The forecast indicated that relatively dry weather would continue for a fairly long time during the day on October 1, while the possibility of precipitation would increase toward the evening, particularly into the early hours of October 2.
For October 2, several forecast models indicated more unsettled weather in Braunschweig. The European Centre for Medium-Range Weather Forecasts (ECMWF) artificial intelligence forecasting model expected 12 liters per square meter, while the average of other forecasts was approximately 5 liters. Given the difference between the figures, it is difficult to state the amount of rain as a single value with certainty.
A Warning Was Not Issued Based on ‘Possibility’ Alone
There was no indication that a comprehensive severe-weather warning or an extreme severe-weather warning covering all of Hamburg and Hanover had been issued by the evening of September 30. The Meteorological Service’s explanation concerned the potential risk that individual thunderstorms and localized heavy rain could develop.
Actual official warnings apply when the Meteorological Service issues them for a specific area. The most important point in this weather change is that, even though the possibility of rain and thunderstorms was presented across a broad area, it was not possible to determine precisely from the forecasts at that time in which city and during which hours the conditions would become severe.
References
- t-online Braunschweig, Cold front approaching Lower Saxony
- Münster Aktuell, Rain and thunderstorms reaching Hamburg and Hanover
Tags #Thunderstorms #HeavyRain #GermanyWeather #HamburgWeather #HanoverWeather #BraunschweigWeather #LowerSaxony #GermanMeteorologicalService #DWD #PrecipitationForecast #WeatherWarning #LowPressureSystem #OctoberWeather