Severe Storm Risk - Harrisburg/Capitol City Arpt, PA
Severe Storm Risk
-There is a Slight Severe Storm Risk for your location. Continue reading for today's outlook from the National Weather Service's Storm Prediction Center. -------------------- National Severe Storm Outlook THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE SOUTHEAST TO THE MID-ATLANTIC...AND ACROSS PORTIONS OF THE NORTHERN/CENTRAL HIGH PLAINS SUMMARY Scattered severe thunderstorms capable of producing damaging winds and perhaps a couple of tornadoes should occur mainly this afternoon and evening across portions of the Mid-Atlantic into the Southeast. Widely scattered severe thunderstorms are also expected across the northern/central High Plains, with large to very large hail the main threat. ArkLaTex into the Mid-South and Southeast A weakened but persistent MCS continues this morning across AR into northeast TX. This cluster will track east-southeastward towards the lower MS Valley over the next few hours while gradually weakening. But, it should still pose some risk for isolated to widely scattered damaging winds in the short term. The convectively augmented MCV attendant to the ongoing MCS will also move east-northeastward across the lower MS Valley and Mid-South/central Gulf Coast states through the day. Gradual destabilization of a rather moist low-level airmass (surface dewpoints generally in the low to mid 70s) should occur, even with widespread cloudiness hampering daytime heating to some extent. Modestly enhanced westerly mid-level flow associated with the MCV and broad upper troughing over the eastern CONUS should support sufficient deep-layer shear for modest updraft organization. Multiple clusters and perhaps marginal supercells capable of producing mainly scattered damaging winds should develop along/south of a front this afternoon, and spread eastward across much of the Southeast through at least the early evening. A tornado or two may also occur in close proximity to the MCV track, but low-level flow is forecast to be fairly veered and modest. Mid-Atlantic A mid-level shortwave trough will move eastward today from the OH Valley into the Mid-Atlantic. Recent visible satellite imagery shows fairly expansive cloud cover over much of the northern Mid-Atlantic, with clearer skies farther south into southern VA and vicinity. 12Z observed soundings across this region show poor lapse rates aloft, which should hamper any more than weak instability developing this afternoon, even with filtered daytime heating. Still, strengthening mid-level westerly winds and large-scale ascent preceding the shortwave trough will likely encourage scattered to numerous thunderstorms to develop this afternoon across the higher terrain of the central Appalachians and Blue Ridge Mountains. These multicell clusters should pose a threat for mainly scattered damaging winds as they spread east-northeastward towards the Atlantic Coast through the afternoon and evening. Marginal hail may occur with the strongest cores. A couple of tornadoes appear possible along/near a sharpening warm front in the MD/PA/NJ/DE vicinity, where low-level shear may become locally enhanced. Northern/Central High Plains Within a generally zonal mid-level pattern, isolated to widely scattered thunderstorms are expected to develop this afternoon and evening across parts of the northern/central High Plains in a modest low-level upslope flow regime. Moderate instability will be aided by the presence of steep mid-level lapse rates, and 40-50 kt of deep-layer shear will easily support supercells with an attendant threat for large to very large hail. These supercells may be fairly widely spaced, but will likely track south-southeastward through at least the early evening before weakening. A couple of tornadoes may occur with these supercells, particularly across parts of the NE Panhandle into northeast CO, where the best combination of low-level moisture, effective SRH, and favorable convective mode should overlap for a few hours. Latest short-term guidance continues to show low potential for upscale growth/MCS development tonight, but trends will be monitored.