Tornado Risk 4/2/2024 [cid:27a2f1f2-fb17-46a1-9519-1592e1472611] NWS Storm Prediction Center Norman OK 0100 PM CDT Mon Apr 01 2024 Valid 021200Z - 031200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS A LARGE PORTION OF OHIO...AND INCLUDING ADJACENT PARTS OF SOUTHEASTERN INDIANA...NORTHERN KENTUCKY...AND WESTERN WEST VIRGINIA... ...SUMMARY... A potentially substantial severe weather outbreak -- possibly including a few significant/long-track tornadoes -- is evident for Tuesday afternoon and evening, with highest probability centered over the Ohio vicinity, and extending southward across the Tennessee Valley. Some severe risk exists as far south as the Gulf Coast, and as far east as western portions of Virginia and the Carolinas. ...Synopsis... While a positively tilted upper trough moves across the central third of the country Tuesday, a more compact/energetic short-wave feature is expected to dig aggressively/quickly southeastward across the Upper Midwest, gradually evolving into a closed low as it does. By Wednesday morning, the deepening low is progged to reside over the Illinois vicinity. At the surface, a low initially over the Missouri vicinity is progged to deepen as the upper system digs southeastward, shifting northeastward across the Midwest through the day, and then occluding northward into Lower Michigan overnight. A cold front associated with the low will sweep across the Mid Mississippi and Lower Ohio Valley through the day, and the Lower Mississippi/Tennessee/Upper Ohio Valleys overnight, crossing central/southern Appalachian Crest late. Meanwhile, a warm sector should expand as far north and east as central and northeast Indiana/northern Ohio/western Pennsylvania, though limited in northward progress to West Virginia/northern Virginia/Maryland by persistent/slow-to-retreat cold-air damming over the Northeast. ...Ohio and Tennessee Valleys... Widespread thunderstorms -- including some degree of all-hazards severe risk -- will likely be spreading rapidly eastward across the Ohio Valley area at the start of the period. This convection should reach the central Appalachians by late morning/midday, but -- though potentially having some impact on destabilization potential across the MDT and ENH risk areas -- should largely shift far enough east to allow warm-sector destabilization to commence. As the surface low deepens and crosses Illinois and eventually moves into Indiana, and the cold front advances across the Mid Mississippi and Lower Ohio Valleys, storm redevelopment is expected to occur during the afternoon. While evolution/storm mode remains somewhat difficult to discern -- in part due to earlier storms -- some mix of cellular and cluster/linear mode is expected to evolve. Given the ample destabilization expected in combination with very strong/veering deep-layer flow, all-hazards severe potential is evident, including very large hail, strong/damaging winds, and several significant tornadoes. The greatest risk, which will include potential for a couple of intense/long-track tornadoes, should begin across Indiana, and the spread across Ohio through the afternoon and evening, potentially reaching as far east as western portions of West Virginia and far western Pennsylvania into the evening. Eastward advance of the risk into central Pennsylvania will likely remain limited, but otherwise threat may spread into western portions of Virginia and the Carolinas late. ...Florida/Georgia/southeastern Alabama and perhaps into the western Carolinas... Thunderstorm development is expected to increase late in the period from the Florida Panhandle northeastward, ahead of the advancing cold front. With indications of potentially cellular mode with this convection, concerns for a very late-period increase in tornado potential exist, given background shear profiles supportive of updraft rotation. While somewhat uncertain at this point, have expanded 5% tornado probability substantially eastward/southeastward to include this potential. James Hale, ARM-P, ARM-E Risk Control Consultant County Risk Sharing Authority 209 East State Street Columbus, OH 43215 614.246.1630 FAX 614.220.0209 “ The leader in providing Ohio Counties with exceptional value, service, and protection of assets.”
