SPC Jun 24, 2022 0600 UTC Day 2 Convective Outlook

 SPC AC 240450 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1150 PM CDT Thu Jun 23 2022 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SATURDAY AFTERNOON AND EVENING ACROSS PARTS OF SOUTHEASTERN IOWA...NORTHERN AND CENTRAL ILLINOIS...NORTHERN AND WESTERN MISSOURI...EASTERN AND SOUTHERN KANSAS...NORTHWESTERN OKLAHOMA AND THE TEXAS PANHANDLE... ...SUMMARY... Strong thunderstorms may impact a corridor across parts of the middle Mississippi Valley into the Texas and Oklahoma Panhandle vicinity late Saturday afternoon and evening, with a few posing at least some risk for severe wind and hail. ...Synopsis... Models indicate that an increasingly blocked regime centered roughly over the northeastern Pacific will evolve by early this weekend, with a mid-level low (centered near 40N/145W) still more prominent than the mid-level high (centered near the Gulf of Alaska) on Saturday. Within the northern branch of the split downstream flow, at least a couple of substantive short wave perturbations are forecast to progress through northwesterly to westerly flow, around the southwestern periphery of an elongated vortex centered east through north of Hudson Bay. This includes one trough forecast to shift eastward across Manitoba, northwestern Ontario, and adjacent portions of the northern Great Plains into the upper Great Lakes region, providing support for a deepening surface cyclone migrating across northwestern Ontario through the James Bay vicinity by 12Z Sunday. In the wake of this impulse, cool surface ridging appears likely to build southeastward to the lee of the northern U.S. Rockies. Preceding the leading edge of the cooler and drier air, a combination of conglomerate convective outflow and a weak surface cold front may initially extend across the upper Midwest into the lower Missouri Valley and central Great Plains by early Saturday, before advancing southeastward through the Great Lakes, middle Mississippi Valley, and central into southern Great Plains through the period. While the leading edge of the cooler near-surface air advances relatively far south through the Great Plains and middle Mississippi Valley, models indicate that mid/upper ridging will generally be maintained across much of the central and southern tier of the U.S. Highest mid-level heights are forecast to linger across the southern Great Plains and mid/lower Mississippi Valley, with weak embedded troughing centered over the southern Sierra Nevada and offshore of the Atlantic Seaboard. ...Middle Mississippi Valley into Texas/Oklahoma Panhandles... Models suggest that the more appreciable probabilities for thunderstorm development will be largely focused within the milder, but as moist (or more across the Great Plains) post-initial outflow/weak surface front regime advancing southward across the region. Although areas northeast of the Missouri River into the Upper Midwest will be closest to the modest (30-40 kt around 500 mb) southern fringe of the westerlies, stronger boundary-layer destabilization may be confined to areas within weaker flow beneath the warm mid-level ridging. Mid/upper forcing for ascent to support thunderstorm initiation also remains unclear, and may be mostly in association with weak perturbations migrating within the monsoonal regime around the western periphery of the mid-level high. However, it is possible that subtle forcing and perhaps somewhat enhanced shear could contribute to scattered areas of slowly organizing thunderstorm development, near and southwest of the southern fringe of the cyclonic mid-level flow associated with the troughing, late Saturday afternoon and evening. With models indicating that a plume of steeper mid-level lapse may contribute to moderate to large CAPE, some of this convection may become capable of producing severe hail and strong surface gusts near and after peak thunderstorm intensity. ..Kerr.. 06/24/2022 CLICK TO GET WUUS02 PTSDY2 PRODUCT NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z 

Original News Source Link – National Weather Service

Leave a Comment