SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CDT Sat Oct 25 2025 Valid 261200Z - 271200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TODAY THROUGH TONIGHT ACROSS PARTS OF THE CENTRAL AND EASTERN GULF COASTAL PLAIN... ...SUMMARY... Strong thunderstorms may impact the north central into eastern Gulf coastal vicinity this morning, then mainly this evening into early Monday, accompanied by at least some risk for severe weather. ...Discussion... Models indicate that strong, generally zonal mid/upper flow will be maintained across the mid-latitude Pacific into western North America through this period. As one significant short wave trough emerging from this regime progresses northeast of the Canadian Prairies toward the northeastern Canadian Arctic latitudes, another is rapidly pivoting across the northern U.S. Rockies toward the Canadian Prairies. Downstream, amplification of mid/upper flow is already well underway, including building ridging across parts of the Upper Midwest through Ontario and the southern Hudson/James Bay vicinity, and consolidating/digging troughing near the northern Atlantic coast. Models suggest that a closed cyclonic circulation may evolve within the troughing offshore of the New England coast today through tonight, while a short-lived anticyclonic circulation evolves within the ridge across the upper Great Lakes vicinity. To the south of the ridge, a low initially centered over the south central Great Plains may slowly reform eastward across the Ozark Plateau/Mid South, with broadly cyclonic flow to its south overspreading the northern Gulf coast vicinity. Beneath the confluent eastern North American regime, expansive cool surface ridging is likely to persist, and maintain considerable influence as far south and west as the Gulf Coast states into southern Great Plains. However, relatively lower surface pressure may shift east of the southern Great Plains through the lower Mississippi Valley, with perhaps a weak embedded low developing across and east-southeastward offshore of the southeastern Louisiana coastal plain later today through tonight. ...Northern Gulf coast... In association with the evolving pattern, seasonably moist, potentially unstable boundary-layer air is forecast to become largely confined to areas near and offshore of coastal areas. A couple of strong storms may linger from the overnight into early morning across parts of southern Mississippi and southeastern Louisiana. However, the latest convection allowing model output suggests that vigorous thunderstorm development, with at least some potential for evolving embedded mesoscale cyclonic circulations, will mostly accompany the developing weak surface low. The environment most conducive to this may evolve this evening into early Monday near and offshore of the southern Alabama and western Florida Panhandle coast. ..Kerr/Wendt.. 10/26/2025
