SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0759 PM CDT Sat Jun 12 2021 Valid 130100Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated significant severe wind and hail are possible this evening across parts of the southern High Plains. Marginally severe wind gusts will also be possible in parts of the lower Ohio Valley and Southeast. ...Southern High Plains... An upper-level ridge is located from the southern Rockies into the central Plains. Beneath the ridge, a moist airmass is in place across much of the southern High Plains. A strong west-to-east gradient of low-level moisture is located across eastern New Mexico and west Texas. Surface dewpoints along this gradient are mostly in the 60s F, with the RAP analyzing MLCAPE generally in the 3500 to 4500 J/Kg range. Two clusters of strong to severe thunderstorms are ongoing. The first is in southeast Colorado and the second is in northeast New Mexico. These clusters are expected to move east-southeastward along the corridor of moderate to strong instability this evening. Forecast soundings at 03Z this evening across far northeast New Mexico into the western Texas Panhandle have directional shear in the low-levels with west-northwesterly mid-level flow. This is contributing to 0-6 km shear in the 30 to 35 kt range. The moderate deep-layer shear combined with mid-level lapse rates near 8.0 C/km should be favorable for supercells with large hail. The more dominant supercells may be able to produced hailstones greater than 2 inches in diameter. As low-level flow strengthens this evening and the two clusters move east-southeastward, cold pool development will be possible. Wind damage will be likely along the leading edge of any line segment that can become organized. Wind gusts over 65 knots will be possible. ...Lower Ohio Valley... The latest water vapor imagery shows a shortwave ridge located over the lower Great Lakes. A cluster of strong to severe thunderstorms is ongoing just to the west of the shortwave ridge from south-central Illinois into north-central Indiana. The storms are located on the northeastern end of a corridor of moderate instability. The RAP is estimating MLCAPE across south-central Illinois and western Indiana in the 2500 to 3500 J/kg range. This combined with steep low-level lapse rates will be sufficient for marginally severe wind gusts with the stronger multicells early this evening. ...Southeast... A very moist airmass is in place across much of the southeastern United States. Scattered thunderstorms are ongoing in this moist airmass, mainly across west-central Alabama and eastern Georgia. In addition to surface dewpoints in the lower to mid 70s F, the RAP is estimating MLCAPE from 2500 to 3500 J/kg. This combined with steep low-level lapse rates will be sufficient for marginally severe wind gusts for another hour or two mainly in areas where convection is already ongoing. ..Broyles.. 06/13/2021 Read more LIVE: spc.noaa.gov
http://dlvr.it/S1cnD1
