Influence of embedded convection on precipitation amounts.

Subject of this poster is to closely examine the influence of an embedded convection during the severe floods in September 2024. During this high impact situation, several bands of convection affected areas in eastern parts of Czechia and western regions of Slovakia and enhanced the precipitation amounts significantly. The combination of convective precipitation and upwind effect caused a numerous absolute precipitation records in both countries. For example in Slovakia, a new record was set for 48 hours (267,3 mm - Borinka weather station) and 5 days (379,8 mm - Pernek weather station) total precipitation. In Czechia, 385,6 mm was measured at Švýcárna automatic weather station and marked this number like a new absolute 24 hours record.

Wider forecaster perspective in these situations is focused mainly on orographic effects of precipitation in complex orography which enhance the overall sums of rainfall. This phenomena is well known for forecasters and the skill of high resolution numerical models to simulate these effects is usually quite acceptable. On smaller scale however, embedded convection can also play significant role in overall contribution of precipitation amount and precise forecast of these very local bands of higher precipitation amounts is very challenging. We tried to compare the regions, where upwind effect was mainly responsible for the highest precipitation and regions where this effect was boosted with the presence of embedded convection. We examine other similar situations from the past as well, floods in 1997, 2010, 2018, etc.