Monday, August 22, 2011

Severe thunderstorm forecast for tonight & tomorrow.



For tonight the high pressure/ridge is forecasted to push East of the area….Warm front/short wave is forecasted to push into the FA…This will allow for WAA to kick in along with a strengthen LLJ later today and tonight…

Thunderstorms are forecast to fire up over in MN later this afternoon and evening then push towards the forecast area tonight….Thinking as of right now our severe weather threat won’t happen till after 11 PM or slightly later….

Problems with this are Nam and GFS aren’t in the best agreement, though Nam has slowly begun to agree with GFS…. GFA has more of a Southerly forecasted while NAM is more North…..The only real impact I see with this is my Northern Counties may not see much of anything if GFS verifies… So have blended both models to come up with the map below……Thunderstorms are forecasted to form into an MCS tonight and push into the FA….Main threat from severe thunderstorms will be large hail and damaging winds, along with the possibilities of heavy rainfall amounts…..


The severe weather threat will be ongoing in the morning as MCS move through the area…. Later in the day a cold front is forecasted to move into the FA this should set the stages for more thunderstorms….Here is where a big problem shows up to the severe weather threat…. 1. How fast can we break into some sunshine to get SFC going….2. How strong will the cap get if we do break into some sunshine….So have based map on a blend of models and some past severe weather setups that are close to this one… This may have to be change later this evening or tomorrow morning….


Colors for the map…

Green small chances of severe thunderstorms.

Yellow a better chance of severe thunderstorms.

Red the best chance of severe thunderstorms.