SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Mar 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF NORTHERN OKLAHOMA...EASTERN KANSAS...WESTERN/CENTRAL MISSOURI... ...SUMMARY... Scattered severe thunderstorms are possible from northern Oklahoma into the Lower Missouri Valley on Saturday evening/night. Large to very large hail should be the primary hazard, but a couple of severe gusts and possibly a tornado or two may occur. ...Synopsis... The upper-level pattern across the Rockies and Plains will be somewhat disorganized. However, two low-amplitude shortwave troughs are expected to eject into the Plains during the period. At the surface, an initial surface cyclone in western Kansas will evolve into two distinct lows as the two shortwave troughs eject in succession. One low will move through the lower Missouri/mid-Mississippi Valleys while the other will shift through western/central Oklahoma before weakening by Sunday morning. ...Eastern Kansas/western/central Missouri/northern Oklahoma... Dewpoints should increase ahead of the dryline/cold front during the day. Most model guidance suggests upper 50s to low 60s F will be possible. Confidence in storm development is highest in these areas. Forcing for ascent from the secondary shortwave trough, surface low/dryline, and the cold front should promote widely scattered to scattered storms initially from north-central Oklahoma into northeast Kansas. Effective shear will be strong enough for supercells. Near the triple point into southeast Kansas, supercell structures have potential to last longer into the evening given the more orthogonal shear vector orientation to the dryline. From the Flint Hills into northeast Kansas, supercells would likely persist for a short period. Very-large hail is possible with any supercell, but will become less likely with time as storms will tend to congeal along the cold front in eastern Kansas. Given that the boundary layer will be rather well-mixed and the low-level jet will increase during the evening, some upscale growth into one or more clusters seems probable. Large to very-large hail will be the primary threat. Isolated severe/damaging gusts and perhaps a tornado or two are also possible. The primary area of greater tornado risk, conditional on supercell storm mode, will likely be from northeast Oklahoma into southeast Kansas where low-level hodographs will be more favorably curved/enlarged. There is some question how far east strong/severe storms will persist into Missouri. The current Slight risk has been maintained as is, but model trends will continue to be monitored. ...Central/western Oklahoma into Central Texas... In Oklahoma, capping from an elevated mixed layer should suppress convection along the dryline through the afternoon. With 850-700 mb winds generally veered in the vicinity of the dryline, it becomes rather uncertain if convection will be able to initiate given parcels short residence time in the narrow zone of ascent. Furthermore, mid-level ascent will not arrive until after sunset. Models continue to show a very weak signal for any development as a result. Should a storm or two manage to develop, the environment will be conditionally favorable for supercells capable of large/very-large hail, severe winds, and perhaps a tornado. Farther south into Texas, a similarly capped environment will exist. Stronger heating may lead to a few convection initiation attempts along the dryline (a scenario hinted at by the ECMWF/GFS as well as some CAMS). Additional potential will exist in far southern Oklahoma/North Texas near a triple point feature along with a strengthening low-level jet core. Isolated large to very-large hail and severe gusts would be the primary threats with this activity, should it develop. ...Lower Missouri into mid-Mississippi Valley... The lead shortwave will promote a surface low to deepen in the Kansas City vicinity and track roughly north-northeastward through the evening. A few, likely elevated, storms could produce large hail given the steep lapse rates aloft. An isolated strong/damaging gust is also possible but should be spatially limited and conditional on a more organized cluster developing. The northern and eastern extent of the threat are the most uncertain for these region. ..Wendt.. 03/28/2025