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| Today's Overall Risk of Severe Storms |
A severe weather event is likely today.
DISCUSSION
An upper level low will eject into the Central Plains this afternoon. Out ahead of this, a strong low level jet stream will be in place in the Central/Southern Plains. With existing moderate to high instability, this jet stream should be able to produce decent shearing in the atmosphere.
This morning, the first round of storms is expected to be fairly strong, and affect portions of Texas as a weaker shortwave pushes through. There is a potential hail threat with this first round.
This afternoon is when the show begins. The cap is expected to weaken sometime this afternoon. As soon as that cap breaks, scattered storms will develop along the dryline separating the humid and dry air masses. That dryline will be located on the western edge of the moderate risk.
With the strong instability and increasing deep layer shear, these storms do have tremendous potential to go supercellular.
Initiation of convective storms should begin in North Kansas. Soundings indicating CAPE values of 1500-2500 j/kg, combined with shearing of 40 kt, will provide the base for supercells and bowing segments capable of large hail.
These bowing segments will have a little more chance of tornadoes than squall lines, because the line of storms if in a half circle and the cells aren't completely locked in.
Further south from North Kansas into Oklahoma, forecast CAPE values rest at 2000-3000 j/kg with potential shearing at 40 knots, increasing to 70 knots as the low level jet stream moves in the area.
Large hail is extremely favored in this area for storms that develop. An isolated strong tornado threat is on the table for the stronger supercells.
The wild card right now is how much of the area will get impacted by these storms. The NAM is favored by the SPC. The NAM is depicting the storms as widely gapped. However, with this being a bigger severe weather threat, the SPC has opted to keep the moderate risk.
In the Carolinas and Appalachians, high CAPE values up to 3500 j/kg and deep layer shear of 45-50 knots will be sufficient enough for potential supercells to erupt. However, based on how small this area of slight risk is, I am expecting only a few supercells. In any case, the main threats will be isolated hail/damaging wind threats.
In the Mid/Upper MS Valley, intense CAPE values up to 4000 j/kg are possible. However, with little large-scale lifting, only a few storms may initiate from Southern Minnesota into Eastern Iowa into Wisconsin and North Illinois. These few storms would contain a marginal wind damage threat and some hail potential. These storms would be initiated by about noon CDT.
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| Today's Hail Threat |
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| Today's Tornado Threat |
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| Today's Damaging Wind Threat |
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