SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 10 2025 Valid 101630Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF SOUTHEAST NM AND FAR WEST INTO CENTRAL TX... ...SUMMARY... Severe storms are expected to develop this afternoon and evening across parts of far southeast New Mexico, far West Texas and the Rio Grande Valley. Marginally severe storms will be possible from parts of the southern Plains eastward into the lower Mississippi Valley, along parts of the Atlantic Coastal states, in northern California/southern Oregon and in parts of the northern Rockies. ...Central/East/Southeast TX... Recent satellite/radar imagery shows a decaying MCS across central TX. The airmass downstream across east/southeast TX is very moist, with dewpoints in the 70s, which will support strong buoyancy amid continued daytime, with MLCAPE likely over 2500 J/kg. However, vertical shear is weak and the general expectation is for the strength of the MCS to remain modest, with only limited re intensification anticipated. Any reintensification appears most likely along the northern portion of the MCS, where interaction with a warm-front-like boundary demarcating more tropical air is likely. This may lead to some forward propagation and an increased potential for a few locally stronger gusts. ...Southeast NM/Far West into Central TX This Afternoon/Evening... Easterly/southeasterly winds are expected to result in notable low-level moisture advection into the region throughout the day. This increased low-level moisture beneath steep mid-level lapse rates will support moderate to strong airmass destabilization amid daytime heating this afternoon. Low-level convergence and orographic ascent coupled with strengthening large-scale lift ahead of an approaching shortwave trough will foster severe thunderstorm development this afternoon across southeast NM and far west TX. Large to very large hail (3"+ in diameter) is the primary risk with the more cellular, early stage development. Upscale growth is then expected, with the resulting convective line progressing southeastward into the Edwards Plateau/central TX vicinity. The hail threat will persist, but strong wind gusts will become the primary risk once the linear mode dominates. ...Central Portions of the Southeast into Mid-Atlantic... Recent surface analysis places a weak trough from northern MS eastward through northern GA then northeastward across the Carolina Piedmont to a low over the Chesapeake Bay vicinity. This boundary will provide the impetus for scattered thunderstorm development as it gradually shifts southeastward as a more cold-front-like feature later this afternoon and evening. The downstream airmass will be moderately to strongly buoyant, but shear will be weak, leading to a predominantly disorganized multicellular mode. A few strong downbursts are possible as storms collapse and/or briefly surge as bowing line segments. ...Eastern FL Peninsula... Full daytime heating and dewpoints in the 70s will yield strong instability later this afternoon along the northeast and east-central FL peninsula, supporting scattered thunderstorm development. Weak but sufficient deep-layer shear and steep low-level lapse rates could result in locally damaging wind gusts in the strongest cells. ...New England... Recent surface analysis places a cold front from eastern Lake Erie southwestward through far western NY and PA, well to the west of the warm conveyor showers and thunderstorms currently ongoing across much of New England. Modest destabilization is anticipated ahead of the cold front, with scattered thunderstorm development anticipated along this boundary as it moves eastward this afternoon. Buoyancy will be modest, but strong mid-level flow and resulting strong shear should still support organized storm structures this afternoon/evening. Some isolated hail and/or damaging gusts are possible within the strongest updrafts. ...Pacific Northwest into the northern Rockies... Upper ridging will continue to dampen across the region while mid-level southwesterly/westerly flow aloft gradually strengthens ahead of an approaching low-amplitude shortwave trough. Orographic effects coupled with increasing mid-level moisture and modest large-scale ascent will support thunderstorms over the higher terrain, with some of these storms tracking eastward/northeastward into lower elevation areas. Greater lower elevation destabilization is anticipated the southern/southeast OR vicinity and the lee of northern Rockies in western/central MT. Damaging gusts are possible later this afternoon/evening as high-based storms moved into these regions. Some isolated hail may occur as well. ..Mosier/Thornton.. 06/10/2025