Severe Weather Outlook for April 30, 2017
This page has information on possible severe weather tomorrow as provided by the Weather Service Storm Prediction Center. You can also view outlooks for today, and the day after tomorrow. The day two outlook is normally updated around 2 AM and 2 PM Eastern time.
Refer to the text discussion below the map for descriptions of possible severe weather threats.
Hazardous Weather Forecast Maps:
Severe Weather Discussion:
000 ACUS02 KWNS 291732 SWODY2 SPC AC 291732 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 PM CDT Sat Apr 29 2017 Valid 301200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM MISSISSIPPI AND ALABAMA NORTHWARD INTO THE LOWER OHIO VALLEY... ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL GULF COAST NORTHWARD INTO THE MIDDLE MISSISSIPPI VALLEY AND SOUTHERN GREAT LAKES... ...SUMMARY... Severe thunderstorms will be possible across portions of the lower/mid Mississippi Valley eastward to Alabama Sunday into Sunday night. Damaging winds will likely be the primary threat, but a few tornadoes may also be possible. A couple strong/severe storms may also occur Sunday over parts of the Ohio Valley and southern Great Lakes. ...Synopsis... A large mid-level closed low will lift northeast from the southern/central High Plains to the Midwest, as a shortwave trough rotates around its periphery from Texas into the Ohio Valley. In turn, expansive cyclonic flow aloft should establish over much of the contiguous US on Sunday. ...Portions of the mid/lower Mississippi Valley and eastward... With such an amplified system and strong meridional flow aloft, multiple areas of convection will likely be ongoing Sunday morning. The main influencing factor regarding timing and location of potential severe weather will be with one or more north-south oriented bands of storms across parts of the lower/mid Mississippi Valleys, likely in advance of the surface cold front. The latest convection-allowing model guidance converges towards a scenario with the placement of a north to south oriented squall line at 30/12z located from western TN/eastern AR south into northern LA and southwestern LA. A squall line is forecast to continue eastward across the lower Mississippi Valley into AL where a moisture-rich airmass will support moderate buoyancy. Despite the presence of enlarged low-level hodographs, a linear convective mode (nonsupercell) is forecast and will likely limit the overall tornado risk. Additionally, 0-3 km shear vectors with respect to projected line segment motion will be suboptimal for a heightened mesovortex tornado risk, although the moist low levels may support some low-tornado threat. Strong to severe gusts capable of wind damage are forecast to be the primary severe hazard and could concentrate primarily near LEWP/bowing structures in the QLCS. This band is forecast to gradually weaken with eastward extent as it outpaces large-scale ascent and encounters increasing inhibition. Behind these storms, uncertainty exists with the potential for re-development of convection along the front (due to prior convective overturning). Across the mid Mississippi Valley, a highly conditional risk for severe weather is apparent owing to destabilization concerns via widespread convection from both clouds/early-day precip and widespread thunderstorms located to the south during the morning. If strong updrafts manage to develop coincident with peak heating, storms within a portion of this region may yield a localized wind/tornado risk before diminishing in intensity during the early evening. ...Portions of northern OH into northwest PA... Modest warm advection in the vicinity of lift from a west-east warm frontal zone over the area may result in isolated storms during the afternoon. A couple of locally strong storms may yield the risk for isolated marginally severe hail/damaging winds. ..Smith.. 04/29/2017 $$