Storm Prediction Center
No watches are valid as of Sat Aug 13 11:46:01 UTC 2022.
No Mesoscale Discussions are in effect as of Sat Aug 13 11:46:01 UTC 2022.
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Sat Aug 13 2022 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN GEORGIA INTO THE CAROLINAS AND SOUTHERN VIRGINIA... ...SUMMARY... Isolated strong to severe thunderstorms may occur Monday across parts of eastern Georgia into the Carolinas and southern Virginia. ...Eastern Georgia into the Carolinas and Southern Virginia... A large-scale upper trough should remain over much of the eastern CONUS and Canada on Monday. A belt of modestly enhanced mid-level northwesterly winds is forecast to persist from parts of the OH/TN Valleys into the Southeast. At the surface, low-level moisture should gradually increase ahead of a front that should move east-southeastward across the central Appalachians into the Southeast and southern Mid-Atlantic. Weak to moderate instability should develop ahead of this boundary by Monday afternoon as diurnal heating occurs. Low-level lapse rates are also forecast to steepen, especially ahead of convection that may be ongoing Monday morning. Deep-layer shear appears strong enough for organized updrafts, and most guidance shows the potential for one or more clusters of surface-based thunderstorms to develop along/ahead of the front and spread east-southeastward through Monday evening. A Marginal Risk has been included where the best signal for robust convection exists Monday afternoon, from parts of eastern GA into the Carolinas and southern VA. ...Central Plains... A surface low should be present over KS into southern NE on Monday, with rich low-level moisture extending in a narrow corridor from the Southeast into the Ozarks and central Plains. An upper ridge will likely remain prominent over much of the western CONUS into the southern Plains, with nebulous large-scale forcing aloft over the central Plains. Even so, a ribbon of moderate instability may develop across parts of NE/KS by late Monday afternoon along the axis of greater low-level moisture. A large degree of uncertainty remains regarding potential for surface-based thunderstorm development. But, if any convection can develop across the narrow warm sector, it would have the potential to become severe given the favorable instability and sufficient deep-layer shear forecast. Have opted to not include low severe probabilities for now, as the severe threat appears rather conditional on thunderstorms developing. ..Gleason.. 08/13/2022Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Sat Aug 13 2022 Valid 161200Z - 211200Z ...DISCUSSION... Little change to the upper pattern should occur through at least the middle of next week, with a large-scale upper ridge remaining over much of the western/central CONUS, and an upper trough over the eastern states. Organized severe thunderstorm potential also appears relatively low, as modest mid-level winds should generally limit deep-layer shear. From Day 4/Tuesday through Day 6/Thursday, the best potential for occasionally strong convection should focus along and south of a front that is forecast to slowly sag southward across parts of the southern Plains into the lower MS Valley and Southeast. Modest mid-level northwesterly winds may exist between the upper ridge and trough across portions of these regions. Still, deep-layer shear appears too weak to support more than an isolated threat for marginally severe thunderstorms each afternoon. The potential for the upper ridge to be suppressed by a weak mid-level perturbation from Day 7/Friday into next weekend remains unclear. If this evolution occurs and an upper trough can develop across parts of the north-central states towards the Great Lakes vicinity, then some severe risk may ultimately develop across parts of the central/eastern CONUS in this time frame. However, organized severe thunderstorm chances still appear rather low, as a fair amount of uncertainty remains regarding the possible upper ridge breakdown.Read more