Cold front to bring storms, rain up to 50 mm and a 10-degree temperature drop across Poland
A cold front will sweep across Poland from the northwest overnight on 16 August, bringing storms, locally heavy rain and a temperature drop of roughly 10 degrees C by Monday, according to IMGW forecasts.
Heat before the front
Saturday will close out the warm spell with clear skies and temperatures ranging from about 26 degrees C on the eastern coast near the Gulf of Gdansk, through 31 degrees C in the centre, to 35 degrees C on the western edges of the country. A high-pressure system labelled Ralf will sit over the Balkans on Sunday, while a low-pressure trough linked to a system called Margarete over Scandinavia and the northern Baltic will drive a cold front into Poland from the northwest overnight. IMGW forecaster Przemyslaw Makarewicz told Radio ZET that the zone of highest temperatures will shift toward the country's southeast as the front advances.
Sunday: a divided country
On 16 August, Poland's weather will split. The southeast will stay sunny or nearly cloudless, while the rest of the country sees increasing cloud cover, passing rain and local storms with hail. The south will remain the warmest region at up to 34 degrees C, with the centre reaching about 30 degrees C, Pomerania 21 to 24 degrees C, and the immediate coast 19 to 21 degrees C. Rainfall in the front zone is forecast at 10 to 15 mm, with wind gusts up to 60 km/h; during storms, gusts may reach 65 km/h. TVN24's forecast notes that relatively low humidity in the frontal zone may cause it to dry out in places, limiting severe storm development in the centre, while the northeast and the Sudetes are the most likely areas for stronger thunderstorms.
- South
- 34 °C
- Centre
- 30 °C
- Pomerania
- 24 °C
- Seaside
- 21 °C
Overnight storms and Monday's cooldown
During the night of Sunday into Monday, storms are expected in a belt running from eastern Mazovia and the Lublin region, through the Lodz and Kielce areas and northern Silesia, to Opole and Lower Silesia, with rainfall up to 25 mm. Minimum temperatures will range from 11 degrees C in the north to about 15 degrees C in the centre and 19 degrees C in the south. On Monday, the front will move over southern and southeastern Poland, bringing heavier rain, particularly in the Carpathian belt. Rainfall may reach 35 mm locally, with TVN24 citing up to 50 l/sq m in the south. Temperatures will drop to about 20 degrees C in Pomerania, 23 degrees C in the centre, and up to 30 degrees C in the southeast, with roughly 19 degrees C at the coast and in Podhale. Wind gusts during Monday's storms may reach 70 km/h.
- Cold front enters from the northwest; rain 10-15 mm, gusts 50-60 km/h
- Front drifts southeast; storms, hail, gusts to 65 km/h; south still up to 34-35 degrees C
- Storms from eastern Mazovia through centre to Lower Silesia; rainfall to 25 mm
- Front over south and southeast; rain to 35-50 mm, gusts to 70 km/h; cooling to 20-23 degrees C in centre
What drives the change
IMGW reports that Poland will sit under a low-pressure trough associated with a low over Scandinavia. A wavy cold front will drift slowly from the northwest, with cooler polar maritime air from the North Atlantic displacing the tropical air mass that has lingered over southern, central and eastern regions. Pressure in Warsaw at noon on Sunday is forecast at 997 hPa, with a rise expected. Anna Gryczman, an IMGW synoptic, attributed the warmth to a foehn effect driven by the southwesterly direction of the incoming air.
This is a foehn effect, resulting from the direction of air inflow from the southwest. In the remaining area the wind will be southerly, but behind the front it will start turning northwesterly.
Outlook beyond Monday
From Tuesday, the weather will turn variable, remaining rather warm but with periodic passing rain and storms, according to Gryczman. The front's passage will leave most of the country cooler and more unsettled than the weekend, with temperatures oscillating around 20 degrees C and rain affecting nearly all of Poland.
