A Bow Echo

An early morning bow echo approaching the Bucharest area. Seen on Radar (with a zoom around Bucharest). visible sat chanel (from sat24.com) and RGB-airmass product (EUMETSAT,NMA).
The dry air behind the system (west of Bucharest), is the trigger of the bow, but the rear inflow jet is high, so instead of wind, a rain-pool can form with a flash-flood.

Heavy rain is expected.