Dan Robinson
EF5
The first potentially major chase event in the Great Plains this spring will be the second of a two-day sequence brought by the western longwave trough as a potent shortwave ejects into the southern/central Plains on Friday, March 6.
The GFS paints the most favorable picture for tornadoes, with not only a negatively-tilted wave wrapping the warm sector back into the surface low near Sioux City, but the dryline is shown being the initiating boundary all the way up into the low. The Euro, GEFS ensembles and the NAM however depict a much less appealing configuration, with the wave remaining positively tilted and boundary-parallel flow over a southwest-to-northeast oriented cold front. The other big negative is that all of the models have 700mb temps topping out at 6C, with nothing resembling a functional cap in forecast soundings anywhere in the warm sector.
At this time, the GFS's more classic-looking setup unfortunately is the outlier. Even if it wasn't, the lack of capping and strong forcing favors early upscale growth - and a cold front with boundary-parallel flow would just further encourage that outcome. There is a possibility for the other models to come around on the orientation of the synoptic features, but even then, it doesn't appear we'll have the benefit of a capping inversion to keep early upscale growth at bay.
Right now this doesn't look like a "fly or drive across the country/world" setup to jump on, but certainly a good season opener for the Plains.
The GFS paints the most favorable picture for tornadoes, with not only a negatively-tilted wave wrapping the warm sector back into the surface low near Sioux City, but the dryline is shown being the initiating boundary all the way up into the low. The Euro, GEFS ensembles and the NAM however depict a much less appealing configuration, with the wave remaining positively tilted and boundary-parallel flow over a southwest-to-northeast oriented cold front. The other big negative is that all of the models have 700mb temps topping out at 6C, with nothing resembling a functional cap in forecast soundings anywhere in the warm sector.
At this time, the GFS's more classic-looking setup unfortunately is the outlier. Even if it wasn't, the lack of capping and strong forcing favors early upscale growth - and a cold front with boundary-parallel flow would just further encourage that outcome. There is a possibility for the other models to come around on the orientation of the synoptic features, but even then, it doesn't appear we'll have the benefit of a capping inversion to keep early upscale growth at bay.
Right now this doesn't look like a "fly or drive across the country/world" setup to jump on, but certainly a good season opener for the Plains.
