Is Dorothy Going to Fly? Several Tornadoes, Damaging Winds, and Large Hail Are Possible This Weekend During a Multi-Day Severe Weather Outbreak

Time to Make Dorothy Fly...    

Get Dorothy ready, she's going to be flying this week as the Midwest, Southeast, and East Coast prepare for a multi-day severe weather outbreak this weekend. Several tornadoes possible, including a few strong ones possibly on Saturday with widespread damaging winds in excess of 70 mph and large hail expected. A powerful surface low in association with a mid-level shortwave tough will provide the initial setup, followed by another mid-upper level trough leading to a secondary surface low development in the southeast on Saturday, giving rise to a multi-day and multi-state outbreak. Here's how we expect things to shake out as it stands now. 

SPC Day 2 Categorical Risk. A "Moderate Risk" (Level 4/5) was issued for portions of Illinois, Missouri, Tennessee, and Kentucky for widespread damaging winds, hail, and tornadoes


SPC Day 3 Categorical Risk. A "Moderate Risk" was also issued for portions of Mississippi, Alabama, and Louisiana. Strong tornadoes, damaging winds, and hail are all possible  

SPC Day 4 Categorical Risk. A "Slight Risk" was issued for most of the eastern seaboard for the possibility of damaging winds and a few tornadoes

Friday Afternoon and Evening (3/14): 

By Friday afternoon and evening, a powerful surface low will eject across the plains and the upper mid-west region with very supportive upper level winds via a midlevel shortwave trough. This will support the development of a strong cold front, robust enough moisture advection northward, and provide plenty of wind sheer aloft. A Quasi-Linear Convective System (QLCS is basically a line of strong thunderstorms) is expected to form along the cold front and sweep through the midwest, bringing the risk of widespread damaging winds and spin up tornadoes with any supercellular structures embedded within the line. The potential for a few isolated/supercells remains unknown across the southern part of the risk area but if they do form, there would be larger tornado potential. 

GFS 18Z Forecast for Friday Afternoon and Evening. The GFS has been consistently showing the development of a very strong, sub 980 mlb surface low and a powerful line of storms crossing the plains during the day. 

Saturday Afternoon and Evening (3/15): 

        This is where things get complex and potentially most dangerous. By Saturday, the original surface low will eject into the Great Lakes region. This will be followed by a secondary mid-upper level impulse ejecting into the southeastern US and the quick development of a secondary area of low pressure at or near the Tennessee Valley. This secondary low and impulse will kick off additional severe thunderstorm development during the day Saturday. 
GFS 18Z Forecast for Saturday Afternoon. Notice the secondary low development over the Tennessee Valley near the risk area (red circle). 

        Models have indicated the potential for robust enough instability to build in, cold temperatures aloft to promote stronger updrafts, and very strong wind sheer to support the development of a mixture of supercells and convective lines. Any supercells that can form will be in an environment ripe for tornadoes, including strong and possibly long-tracked. Saturday looks to have some higher-end parameters in place for this time of year and could be the day to watch across Dixie Alley. 



GFS Forecasted Weather Sounding for Alabama on Saturday. As indicated, environment looks supportive for severe weather, including strong tornadoes

Sunday Afternoon and Evening (3/16): 

        Here's where things get interesting for us here in RVA. As we head into Sunday, the mid-upper level trough and surface low will eject east-northeastward into the Mid-Atlantic. A strong cold front will approach the region during the afternoon and evening, potentially triggering the development of a squall line in a highly sheared, weakly unstable environment. Damaging winds and a few spin-up tornadoes will be possible as the line approaches Richmond. The GFS has been showing the development of this line during the afternoon. 

GFS 18Z Forecast for Sunday Afternoon. GFS has been consistently showing a strong line of storms developing over the Carolina's and Virginia with damaging wind potential. 



Stay tuned for updates and be sure to check your local meteorologists for all the latest updates. 


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