


Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
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801 ACUS01 KWNS 242009 SWODY1 SPC AC 242007 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0307 PM CDT Sat May 24 2025 Valid 242000Z - 251200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS OKLAHOMA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE FRONT RANGE...SOUTHERN PLAINS...SOUTHEAST... ...SUMMARY... Scattered severe thunderstorms are expected across parts of the southern Plains to the Southeast today. Damaging winds, large hail and a few tornadoes are all possible, particularly across the southern Plains including Oklahoma. Severe storms are also expected in areas including the Colorado Front Range and southern High Plains. ...20Z Update... Given the MCS that has moved through much of Arkansas, severe probabilities have been decreased in parts of central/eastern Arkansas. Elsewhere, the Enhanced risk was modified based to reflect the current position of the outflow boundary. The remainder of the forecast remains unchanged. Please see the previous discussion for additional details. ..Wendt.. 05/24/2025 .PREV DISCUSSION... /ISSUED 1203 PM CDT Sat May 24 2025/ ...ArkLaTex/ArkLaMiss and Lower Mississippi Valley... While the MCS from earlier this morning has tended to trend less intense/organized, diurnal re-intensification is still probable, if not likely, downstream (southeastward) today as convection/cloud cover reinforces the effective boundary that extends east-southeastward across the region. Bouts of damaging winds and hail are the primary hazards. ...Southern Plains including Oklahoma to Ozarks/ArkLaTex... An ample reservoir of low-level moisture and strong to locally extreme potential instability (3500+ J/kg MLCAPE) will reside on the west/southwest fringe of the early morning MCS and related outflow, residual cloud cover, and some regenerative late-morning elevated convection. That said, short-term guidance is rather variable on a sub-synoptic scale as far as boundary modification and north-northeastward placement, while mid-level capping south of the boundary is also a complexifying forecast factor. Potentially intense surface-based storm development appears most probable across Oklahoma near where outflow modifies/intercepts a weak surface wave, coupled with aggressive low-level heating/mixing from the southwest. This could include very large hail (conceivably 2-4") and semi-focused tornado potential contingent upon deep convective initiation. Of somewhat greater certainty is for storms to increase this evening with low-level jet onset/increase, with storms rooted more progressively above a near-surface stable layer with north-northeastward extent tonight. Large hail would be the primary hazard with this activity, with another round of MCS development (and related damaging wind potential) plausible late tonight across eastern Oklahoma toward Arkansas/Ozarks. ...Southern High Plains-Texas Big Country/Low Rolling Plains... As least isolated severe storm development is expected across the region in vicinity of the dry line. Strong heating/boundary layer mixing in the post-dryline environment should be compensatory for mid-level warmth/capping, leading to increasing/deepening convection by late-afternoon peak heating. Deep-layer winds will be weak with only 20-30 kt effective shear (or less), but the thermodynamic environment will support multicells capable of pulse-type/episodic large hail and severe-caliber wind gusts late this afternoon through around mid-evening. ...Front Range/Central High Plains... While a cool/moist air mass and plentiful stratus has persisted across the High Plains, a gradual erosion of stratus has generally be noted in visible satellite imagery more immediately east of the mountains/foot hills including the I-25/urban corridor. Aided by modest low-level upslope flow, strong to severe thunderstorms should develop in this corridor this afternoon, at least on an isolated basis. Severe-storm-conducive buoyancy and steep lapse rates, with adequate deep-layer, would support supercell potential with related risks for large hail and possibly a tornado risk. ...Florida Peninsula... Another day of seasonably cool mid-level temperatures atop a moist low-level airmass combined with strong daytime heating will likely support moderate to locally strong instability across parts of the Florida Peninsula this afternoon. While large-scale forcing for ascent will remain weak, both the Gulf and Atlantic Coast sea breezes should aid in scattered thunderstorm development by peak afternoon heating. Modest deep-layer shear should support some updraft organization, and isolated hail/wind gusts appear possible with any of the stronger cores that sustain. $$