Poland issues storm and gale warnings as Scandinavian low brings 100 km/h winds

Weather front sweeps across Poland

A cold atmospheric front associated with the Scandinavian low-pressure system Bea moved across Poland from northwest to southeast on 20 September. Broad low-pressure centres positioned over the Norwegian Sea and northern Finland influenced conditions across the region, while a high-pressure system remained over the Bay of Biscay. Atmospheric pressure in Warsaw was measured at 1003 hPa at noon before dropping ahead of the front. Synoptician Tomasz Wakszyński warned that multicell storms carried the risk of squall line formations. Around 16:00, storms delivered rain between 15 and 25 litres per square metre and wind gusts of 60 to 80 km/h to areas near Debrzno, Człuchów, Myślibórz, and Nowogródek Pomorski. Sunday maximum temperatures reached 16 degrees Celsius in the north, 20 degrees Celsius in central Poland, and 25 degrees Celsius in the southeast.

Wind and storm warnings across voivodeships

The Institute of Meteorology and Water Management (IMGW) issued yellow first-degree thunderstorm warnings for Pomorskie, Zachodniopomorskie, and northern districts of Lubuskie, Wielkopolskie, Kujawsko-Pomorskie, and Warmińsko-Mazurskie, including Elbląg and Braniewo. These warnings projected rainfall between 10 and 20 millimetres, wind gusts up to 80 km/h, and localized small hail with an estimated probability of 80 percent. Coastal counties in Zachodniopomorskie and Pomorskie were placed under second-degree wind warnings, with average westerly and northwesterly winds reaching 60 km/h and gusts between 90 and 100 km/h. First-degree wind warnings extended to fourteen other voivodeships for gusts up to 80 km/h, while mountain forecasts predicted gusts reaching 100 km/h in the Sudetes and 70 to 80 km/h in the Carpathians. IMGW synoptician Przemysław Makarewicz detailed the progression of the front.

Rain and heavy cloud cover are forecast at the end of the weekend. From Monday, 21 September, due to the passage of an atmospheric front, thunderstorms will occur locally, and the wind will be quite strong throughout the country.

Coastal storm surges and hydrological alerts

Strong northwesterly winds prompted IMGW to issue second-degree hydrological warnings for the entire Baltic coastline. Strong onshore winds pushed seawater towards the coast, creating conditions for water levels to rise into high zones, exceed warning levels, and locally reach flood alarm thresholds. In response, the Government Centre for Security (RCB) dispatched warning text messages across twelve coastal administrative districts, including Świnoujście, Kamień, Gryfice, Kołobrzeg, Koszalin, Sławno, Słupsk, Lębork, Wejherowo, and Puck. The alert warned residents against outdoor exposure during the peak of the storm.

Do not stay or park under trees.

Alert timelines and mountain conditions

First-degree wind warnings across southeastern Poland expire on Monday, 21 September at 05:00, whereas second-degree coastal gale warnings remain in effect until Monday at 12:00. The second-degree hydrological alerts along the Baltic coast stay active until Tuesday, 22 September at 12:00. Overnight rainfall amounts reached up to 12 millimetres in the east and south and up to 15 millimetres in northern districts. High in the Tatras, rain turned to sleet and snow, creating an estimated snow cover accumulation of approximately 5 centimetres with wind gusts up to 80 km/h causing snowdrifts. Overnight minimum temperatures dropped to between 8 and 13 degrees Celsius across the country, falling to 5 to 7 degrees Celsius in foothill areas.