Outlook DAY 1 (valid: 02/09/2019)
Strong upper ridge persists over the N Atlantic and W Europe while a short-wave crosses central Europe with an associated surface cold front. The main deep trough remains over the Arctic region and N Europe while to the east, another strong ridge is located over E Europe and NW Russia. An upper low is located over NW Africa, effecting Iberian peninsula as well.
ENH risk has been issued for NE Italy, N Adriatic into WNW Slovenia and NW Croatia with threat for severe storms, capable of producing severe winds, large hail and torrential / excessive rainfall. Widespread activity is expected along and ahead of the moving cold front with organized storms including a few supercells with bowing segments likely. Clustering into an MCS seems possible in the evening hours when activity arrives over the still very warm Adriatic sea. Pre-frontal training-cells effect is likely across NE Italy and WNW Slovenia as favorable winds / shear are in place, resulting in local flash floods threat. Flash floods and excessive rainfall will also be possible across the SE parts of ENH risk area along the frontal MCS in the evening hours. Strong cold Bora winds are expected behind the front overnight.
SLGT risk has been issued for areas surrounding the ENH risk across the N Mediterranean, N Balkans and into ENE Europe with threat for severe storms, capable of producing severe winds, large hail and torrential / excessive rainfall. Isolated to scattered organized storms are likely to develop by mid/late afternoon under the effect of large-scale ascent associated with the upper wave and the cold front. A few supercells with large hail and severe winds are possible.
MRGL risk has been issued for E Spain with threat for isolated severe storms, capable of producing severe winds, large hail and torrential rainfall.
MRGL risk has been issued for NE Turkey into Georgia with threat for isolated severe storms, capable of producing severe winds, large hail and torrential rainfall.
TSTM risk areas have been placed where convective storms are likely to occur but should remain sub-severe.