Subj : DAY2SVR: Nws Storm Predi To : All From : Mike Powell Date : Wed Apr 29 2026 13:56:00 ACUS02 KWNS 290454 SWODY2 SPC AC 290452 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CDT Tue Apr 28 2026 Valid 301200Z - 011200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE THURSDAY AFTERNOON AND EVENING ACROSS PARTS OF THE RIO GRANDE NEAR THE TEXAS BIG BEND... ....SUMMARY... A couple of strong storms may impact the Rio Grande River vicinity near the Texas Big Bend late Thursday afternoon and evening, perhaps accompanied by at least some risk for severe hail. ....Discussion... It still appears that an elongated area of lower mid-level heights will continue a slow east-southeastward progression across much of the upper Mississippi Valley through northern Atlantic Seaboard, with an embedded cyclonic circulation redeveloping southeastward through the Great Lakes region. In its wake, split westerlies likely will remain confluent across and east of the Rockies, as a short wave perturbation emerges from the subtropical eastern Pacific. There appears a much better consensus within latest model output concerning the inland progression of this perturbation, which is now generally forecast to accelerate across northern Mexico and adjacent portions of the U.S. Southwest, toward the Texas Big Bend vicinity Thursday through Thursday night. Downstream short wave ridging is forecast to gradually shift east of the southern Rockies, across the southern Great Plains through Gulf Coast, while subtropical ridging centered across southern Mexico undergoes further suppression. In lower levels, to the east of the Rockies, cool surface ridging will be maintained across much of the Great Plains and Mississippi Valley into Southeast. Most guidance now indicates that the frontal zone on the leading edge of this air mass will make slow, but steady, southward progress into and across the Texas Big Bend and Hill Country, immediate upper Texas/Louisiana coastal vicinity, and northern Florida. Forcing for ascent associated with lower/mid-tropospheric warm advection, downstream of the approaching subtropical perturbation, may contribute to multiple rounds of thunderstorm development above the stable surface-based air across parts of the Permian Basin and Texas South Plains through much of central Texas by late Thursday night. Based on latest model output, including Rapid Refresh and NAM forecast soundings, thermodynamic profiles seem unlikely to support severe hail. One exception might develop within moist upslope flow into a more strongly heated environment across the higher terrain near and south of the Texas Big Bend. Beneath moderate to strong mid-level flow, the initiation of a couple of supercells appears possible. However, this activity is expected to weaken as it acquires less unstable updraft inflow to the east of the higher terrain. Otherwise, the front might provide a general focus for widely scattered thunderstorm activity near the Gulf coast vicinity, while destabilization beneath cool mid-level air across the Great Basin into southern Rockies supports scattered, mostly diurnal thunderstorm activity. ...Kerr.. 04/29/2026 $$ --- ScorpioBBS/QWK v0.32a (Linux/x86_64) * Origin: ILink: Project Scorpio TEST (454:1/105.6) .