SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Mon Jun 02 2025 Valid 021630Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE TEXAS PANHANDLE AND NORTHWEST OKLAHOMA INTO WESTERN KANSAS... ...SUMMARY... Scattered severe thunderstorms are likely from the Texas Panhandle and northwest Oklahoma into western Kansas. Severe gusts 60-75 mph will be the primary hazard and localized gusts 75-90 mph are possible. ...Southern High Plains into KS... Visible-satellite imagery shows a potent mid-level shortwave trough over AZ, which is forecast to move east-northeastward into northeast NM this evening and south-central High Plains by daybreak. Farther east, a patch of stratus over the northeast TX Panhandle and western OK is attributable to the northwest periphery of richer low-level moisture (upper 60s surface dewpoints) per late morning analysis. The leading band of large-scale ascent with the Desert Southwest disturbance is progressing eastward across central NM southward into southwest TX, as indicated by mid- to high-level clouds and convection. Strong heating will continue this afternoon ahead of the cloud shield across the southern High Plains into eastern CO/western KS. Very steep 0-3 km lapse rates and moderate to very strong buoyancy (1000-3500 J/kg MLCAPE) and eroding convective inhibition, will favor scattered storms developing by mid afternoon on the western part of the moist/unstable sector. Relatively modest mid to high-level flow will favor organized multicells. As storm outflow begins to congeal and as storms move eastward into an increasingly moist airmass (PW rising from 1 inch to 1.5 inches), a propensity for widespread thunderstorms and outflow will peak by early evening. Forecast experience in the combination of PW, buoyancy, sufficient shear for multicells, and high agreement in a linear storm mode, all strongly suggest severe gusts will be the primary hazard. Gusts 60-75 mph will be common with the stronger surges of outflow and localized peak gusts 75-90 mph are possible. Have upgraded to 30-percent significant wind due to confidence in intense outflow. CAMs show this activity spreading east across western and northern OK and into much of central KS before weakening late this evening into the early overnight. ...Central High Plains to MN... A mid-level shortwave trough is forecast to continue eastward across MT and the northern Plains. A surface cold front from northwest MN southwestward into the central High Plains is forecast to focus thunderstorms this afternoon into tonight. Strong heating is expected ahead of this front, where moderate destabilization will be aided by upper 50s to mid 60s surface dewpoints. Initial thunderstorm development is expected during the afternoon across MN where the strongest low-level convergence will be in place. Dewpoints (and overall buoyancy) will be lower here than areas farther southwest, which is expected to limit overall storm strength and contribute to an anafrontal storm character. Farther southwest, isolated storms will probably develop by mid afternoon over southeast WY/NE Panhandle with increasing storm coverage as this activity moves east during the late afternoon/evening. Strong buoyancy will favor robust updrafts, but deep-layer shear will be modest. This weaker shear coupled with linear forcing is expected to result in a quick transition to a predominantly linear mode. As a result, some supercell threat is possible early in the convective evolution but, storm mergers and potential clustering/line segments favor a hail risk transitioning rather quickly to more wind. Some continuation of a severe threat (mainly wind) may persist late into the evening and early overnight across NE, near the terminus of a 45-kt south-southwesterly LLJ. ...South FL... Shortwave trough moving over the central Gulf of America is forecast to continue southeastward into the eastern Gulf, with increasing large-scale ascent downstream across much of the FL Peninsula. Thunderstorm coverage will gradually increase through the mid afternoon with severe/damaging gusts and large hail possible with the stronger cores. This activity will likely weaken by the early evening. ..Smith/Flournoy.. 06/02/2025