Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Fri Jul 24 2020 Valid 261200Z - 271200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY INTO SUNDAY NIGHT ACROSS CENTRAL PORTIONS OF THE GREAT PLAINS AND MID MISSOURI VALLEY INTO THE UPPER MIDWEST... ...SUMMARY... Strong thunderstorms may impact a corridor from the central Great Plains through the Upper Midwest on Sunday, accompanied by at least some risk for severe weather. ...Synopsis... An ongoing amplification within the mid-latitude westerlies may continue and develop eastward along the Canadian/U.S. border vicinity during this period. It appears that this will include further building of mid-level ridging across the Canadian Rockies into the Canadian Prairies. As this occurs, significant downstream troughing is forecast to gradually dig across the international border through northern portions of the Great Plains, the Upper Midwest and Great Lakes region. An associated cold front may advance as far southeast as lower Michigan into the lower Missouri Valley and central Great Plains by late Sunday night. In lower latitudes, models indicate that weak, negatively tilted mid-level troughing will linger across California. At the same time, the weakening remnants of Hanna may continue to slowly migrate west-southwest of the lower Rio Grande Valley, into northern Mexico, to the south of initially prominent mid-level ridging extending along a major axis from the southern Rockies into the lower Ohio Valley. ...Upper Midwest into central Great Plains... Models suggest that stronger cyclonic mid-level flow will continue to lag to the north and northwest of the southeastward advancing cold front. However, within the corridor of stronger pre-frontal boundary layer heating, seasonably high boundary-layer moisture content (upper 60s to lower 70s F surface dew points) is expected to contribute to moderately large CAPE on the order of 2000-3000+ J/kg. Despite the generally weak vertical shear, this will be sufficient to support vigorous convective development, which could become fairly widespread by early Sunday evening, aided by mid-level cooling/forcing for ascent associated with the digging trough. Potential appears to exist for one or two consolidating clusters of storms which could pose an organized strong to severe wind threat before weakening Sunday night. ..Kerr.. 07/24/2020Read more
from SPC Forecast Products http://www.spc.noaa.gov/products/outlook/day3otlk_0730.html
No comments:
Post a Comment