It’s late April in the southern plains, so it’s no surprise we are talking about a few days of severe weather. This Wednesday through Friday (4/22/15 – 4/24/15) look to be potentially active days for severe weather on the southern plains. One or more of these days could feature significant severe weather. The cause of all this is southwesterly flow returning to the southern plains. With sufficient moisture and instability in place, severe weather will be likely, in the presence of very favorable kinematics (wind fields).
Wednesday: Wednesday (tomorrow) looks to be the first in a series of severe weather events across the southern plains. The main threat appears to be across far southern Oklahoma but especially into northern Texas, including far southern/eastern portions of the Panhandle. As mentioned above, southwesterly flow will get established across the region later this evening. In response to this, moisture will be advected northward. A warm front will be draped in some fashion across southern Oklahoma and will be one of the focal points for severe weather.
The threat for severe weather will exist east of the dryline. I think some inhibition will remain across central Oklahoma due to some clouds that may linger, so think the threat will be across far southwestern Oklahoma, along the warm front near the red river and also along the dryline in Texas. Vertical shear and instability are very favorable for initial supercells with all modes of severe weather, including tornadoes, but very large hail will certainly be the most prominent threat. Low level wind shear is not particularly impressive, but persistent cells along the warm front will certainly have a threat of tornadoes. After the initial supercells, storms will congeal into a line and move southeast, possibly impacting areas such as the Dallas metro. If this situation were to unfold as such, higher outlook probabilities may be needed for the area from the Storm Prediction Center.
Thursday’s threat will hinge upon the evolution of Wednesday’s severe event, as is typical, any boundaries that remain could be focal points for convection, etc. The frontal boundary mentioned earlier will sag southward into Texas, thus shifting the threat further south. The main threats right now appear to be large hail and damaging winds. The threat is there for supercells, and with ample instability a tornado threat may also exist. I will post more on this threat soon.
Friday holds the potential for significant severe weather as powerful jet energy overspreads the area. There are still some big timing/evolution differences that need to be ironed out before I go on a limb and make a big forecast.
Concerns (possible negative factors):
- Need mid afternoon initiation along dryline
- Morning Convection
- Models want AM convection that can limit instability
No Concern (good for severe weather):
- Wind Shear
- Very powerful jet stream. No wind shear problems!