Serious potential for strong (tornadic) supercells on June 18th in FVG, Italy

Estofex gave LVL2 for today in N-Italy and the setup really is very good. I won't really into details because time is not on my side. Just a quick writeup. 50 kt 0-6 km shear combined with good SFC winds with nice veering and moderate CAPE values suggests serious potential. The best potential is again in the FVG region where winds are the best. The cap is not small and there is no serious 10m convergence until 18Z so we will see if it can break it anyway. PWAT values are ridiculousy high, in the 42mm range, so everything points to (potentially tornadic) HP supercells. Good luck to everyone who will chase today. I won't be chasing because of college work. :(

April 25–28 Epic tornado outbreak in the USA

A violent tornado outbreak from April 25 – 28, 2011, affected the Southern Midwestern, and Eastern United States, leaving catastrophic destruction behind. At this time there are more than 350 casualties confirmed but the number is still rising.

It was really an amazing setup, just by looking at the numbers. These were the conditions in Alabama:
CAPE : 1000-2000 J/kg
0-6km shear: 70 kts
SREH3: 1100 m2/s2 (!!!)
Significant tornado parameter : 13.0
Supercell composite parameter : >40

These numbers are mind-blowing and we probably won't see this kind of setup for quite some time.

Some interesting images from the supercell that dropped the tornado that hit Tuscaloosa and Birmingham:

Tornado track in Tuscaloosa.

Tornado tracks clearly visible from space. Look how huge the track is! Credit: NASA

Most violent supercell of this tornado outbreak in Alabama.

Crazy hook echo with debris ball.

Small CAPE/large shear setups

In the spring we are dealing with a lot of situations where there is weak or marginal cape and large deep layer and low level shear. These situations can sometimes produce strong tornadic supercells providing large storm relative helicity values. I've stumbled across this interesting point made by Jon Davies on his blog. You can read it HERE.

Similar conditions are currently in southern Poland, Slovakia and further to the south-east. No reports yet. Strong SREH3 is forecast tommorow in the same area with marginal CAPE. Tornadoes are possible.