Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
323 ACUS03 KWNS 181907 SWODY3 SPC AC 181906 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0206 PM CDT Wed Sep 18 2024 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Friday. ...Synopsis... Separate northern-stream and southern-stream mid/upper-level shortwave troughs are forecast to move across parts of the West on Friday, with the northern shortwave reaching the northern Great Plains and Canadian Prairies by Saturday morning. Meanwhile, a stout midlevel anticyclone (with the warmest 500 mb temperatures near or slightly above 0C) will remain anchored over Texas. A weakening mid/upper-level shortwave trough is forecast to move across parts of the Great Lakes and Ohio Valley. At the surface, a weakening cold front will extend somewhere from the south-central Great Plains into parts of the Midwest/Great Lakes by late afternoon. This front may tend to stall with time, and potentially move northward as warm front across the central Plains later Friday night into Saturday morning. A general lack of overlap between favorable moisture/instability and stronger ascent/deep-layer flow is currently expected to limit organized severe potential on Friday. Isolated diurnal storm development will be possible near the weakening front from the Plains into parts of the Great Lakes/Ohio Valley. Elevated storm development will also be possible Friday night into Saturday morning across parts of the central Plains, within a warm-advection regime. It remains uncertain if elevated buoyancy will become sufficient for any hail potential with the stronger storms within this regime. High-based convection that may be capable of localized strong gusts will be possible across parts of the Southwest and southern Rockies, in association with the southern-stream shortwave trough. ..Dean.. 09/18/2024 $$