SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Apr 23 2025 Valid 232000Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN/CENTRAL PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are forecast over parts of the southern/central Plains today and tonight, with large hail and damaging winds possible. ...20z Update... The previous forecast generally remains on track with only minor adjustments needed. A slight westward expansion of 5% hail/wind probabilities across southeast CO where convective initiation is underway along the Raton Mesa upstream of a moist/unstable environment. A significant hail area has also been introduced for portions of western KS where backed low-level flow within a moderately unstable environment (MLCAPE around 2000 J/kg) should promote robust supercells with an attendant large/very large hail threat. Consideration was given to introducing significant hail/wind areas across parts of southwest TX; however, recent ACARS and RAP forecast soundings show somewhat weaker mid-level winds (15-20 knots) compared to yesterday when significant hail/wind occurred in a similar thermodynamic environment. This, combined with the potential for more limited convective coverage, limits confidence in a sufficiently widespread significant hail/wind threat to warrant additional probabilities. See the previous discussion and recently issued MCDs #527 and #528 for additional details. ..Moore.. 04/23/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Wed Apr 23 2025/ ...Central and Southern High Plains... Modest zonal flow pattern persists across the Plains states today, with only weak large scale forcing anticipated. However, strong heating across the High Plains, coupled with circulations along a diffuse dryline and forcing associated with the nocturnal low-level jet will aid in the development of scattered thunderstorms from western KS into the TX Panhandle this afternoon and evening. The area of greatest concentration of storms will likely be over western KS, where model guidance shows greatest confidence in a strengthening low-level jet and some upper support. Storms should develop by late afternoon, with forecast soundings showing sufficient deep-layer shear for supercell structures. Large hail will be the main concern. Low-level moisture will be marginal, but enlarging hodographs by early evening could also support a risk of a few tornadoes. Farther south, thunderstorm coverage will be more widely scattered across the TX Panhandle into the Big Bend region. Nevertheless, steep mid-level lapse rates and sufficient westerly flow aloft will pose a risk of a few supercells capable of large hail and damaging winds through the evening. ...Northeast KS... A small cluster of strong storms has developed this morning over central KS. Several morning CAM solutions suggest an increasing risk of thunderstorm development/intensification by mid-afternoon over northeast KS - in vicinity of a weak surface boundary. While this scenario is unclear, a few of these storms could pose a risk of large hail and gusty/damaging winds. ...Southeast States... Strong daytime heating will aid in destabilization across much of GA/SC this afternoon, with scattered thunderstorm development expected. Winds aloft are weak and storms should be relatively disorganized. However, cool temperatures aloft will aid in a few robust updrafts - posing some risk of hail and gusty winds.