Another Round of Severe Weather for the Area 5/21/14

The Storm Prediction Center has us in a high-end 30% slight risk for severe weather for tomorrow (5/21/14). Remember this means there is a 30% chance of severe weather within 25 miles of a point.

For severe weather we look for 4 main ingredients or SLIM. Shear, Lift, Instability, and Moisture. The setup for tomorrow will not be lacking moisture. The models are forecasting dew points (amount of moisture in the air) into the 70s. Honestly that is probably too high because dew points in the 70s are REALLY high even for summer (which we haven't hit yet) but dew points in the lower to mid 60s are likely and will provide ample energy for the storms.

The map above is a GFS run that shows instability (CAPE) for our area tomorrow. CAPE is often over estimated in the models. This run is showing values of 3000 J/kg for us, which is more than enough for some strong updrafts in the storms tomorrow.

Finally for shear. The forecasted skew-T seen above shows some good speed shear (changes in wind speed with height) but we don't see the directional shear (changes in wind direction with height) that we would need for supercell and tornado development. Also the freezing level (level where temperature = 0 degrees C) is around 600 mbs. Because of the high CAPE values and semi-low freezing layer we could see some hail tomorrow from these storms.

To sum it up. This will be a Wednesday evening, to late evening event. Strong winds and hail are the main threats with the tornado threat looking small.