A potentially significant severe weather event is forecast across a portion of Oklahoma into north Texas late this afternoon into the overnight. Severe storms capable of large to very large hail, a few strong tornadoes, and damaging wind are expected.
Review your severe weather safety procedures for the possibility of dangerous weather today. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. A tornado watch means that conditions are favorable for tornadoes to form during the next several hours. If a tornado warning is issued for your area, move to a place of safety, ideally in a basement or interior room on the lowest floor of a sturdy building.
There is a Moderate Risk or Level 4 threat for severe thunderstorms this afternoon and evening over parts of Oklahoma. All modes of severe weather possible. Tornadoes, widespread damaging wind gusts, and very large hail are forecast this afternoon and evening for portions of Oklahoma and north Texas.
Low-level moisture is being transported across the Southern Plains from the Gulf of Mexico. Dew Points are continuing to rise based on surface observations and are expected to get into the upper 60s or low 70s across the region, indicating a very moist environment. This will help increase surface instability across the region. A dry line to the west will help provide forcing for thunderstorm development.
An increasing low-level jet will help aid in the transport of very moist unstable air poleward over the region. Divergence in the mid-levels accompanied by an approaching shortwave and positive vorticity will aid in enhancing upward vertical motion and mid-level exhaust and cyclonic rotation. At 300 mb a jet finger has branched off the PFJ and is interacting with the STJ creating an area of shared energy over the Southern Plains. These diverging jets are helping support upper-level divergence and exhaust for thunderstorms.
Models suggest moderate instability to build over the region with CAPE values between 2500-3500 j/kg. This is sufficient energy need to support strong thunderstorms with robust updrafts. 0-1km EHI is great at showing us where the strongest surface base instability is while also co-locating the strongest 0-1km shear. SRH values are between 250-350 m2/s2 indicating an environment conducive for supercells and tornadoes including some strong tornadoes. Our forecast sounding shows a high shear and moderately unstable environment. Surface winds are from the south and are veering with height indicating low-level directional shear. This is a vital component for tornado development. Speed shear will help keep the storm organized and increase its longevity as it tilts the updraft of these storms. The hodograph also has a favorable shape for tornadoes given the elongated curved hodograph. 0-6km shear is around 60+kts which is more than enough for organized convection and tornadoes.
Updraft Helicity shows potential updraft tracks of rotating supercells across Oklahoma today.