SPC Feb 3, 2025 1730 UTC Day 2 Convective Outlook
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CST Mon Feb 03 2025 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered weak thunderstorm development is possible along the western slopes of the Sierra Nevada, and near Oregon coastal areas, late Tuesday into Tuesday night. Otherwise, the risk for thunderstorms appears negligible across much of the nation. ...Discussion... Downstream of a blocking high, centered to the southeast of the Aleutians, models indicate that large-scale mid-level troughing will be maintained across and offshore of the Pacific Northwest, though an embedded low may reform to the south-southwest of Vancouver Island. To the east of this regime, large-scale mid-level ridging may continue to slowly build across the northern U.S. Great Plains and adjacent Canadian Prairies into the Great Lakes region, while a short wave perturbation digs within northwest flow to its northeast and east. In a separate branch of westerlies, emanating from the southern mid-latitude Pacific, a notable short wave perturbation is forecast to accelerate inland across the California coast and Great Basin/Rockies by 12Z Wednesday, ahead of an inland advancing perturbation within the more prominent cyclonic regime to the north. In lower-levels, it appears that surface troughing will slowly begin to deepen to the immediate lee of the Rockies, as the center of an expansive cold surface ridge shifts from the Canadian Prairies and northern U.S. Great Plains into the Great Lakes, beneath the more strongly confluent mid-level flow. The shallow leading edge of the seasonably cold air mass may stall across parts of the southern Great Plains into Ohio Valley, while advancing offshore of the northern and middle Atlantic Seaboard. At the same time, a southerly return flow of moisture is forecast to develop from parts of the western Gulf Basin into the southern U.S. Great Plains and lower Mississippi Valley. ...California/Sierra Nevada... In advance of the perturbation emanating from the southern mid-latitude Pacific, low/mid-level moistening, differential thermal advection and strong lift, aided by a strengthening upslope flow component, may contribute to weak destabilization along the western slopes of the Sierra Nevada by Tuesday afternoon. Forecast soundings suggest that thermodynamic profiles may become supportive of convection capable of producing lightning by early Tuesday evening, if not earlier. ...Oregon coastal areas... Models indicate that lower/mid-tropospheric cooling will lead to increasing boundary-layer destabilization near coastal areas through the period. As this occurs, some convection, within a broader area of continuing convective development, may deepen through sufficiently cold layers aloft to support occasional lightning. ...Ozark Plateau/Mid South... Beneath low-amplitude large-scale mid-level ridging across the southern Great Plains through the lower Mississippi Valley and Southeast, it appears that low-level moistening and warming will contribute to increasing potential instability. Models indicate that this will generally remain capped by a relatively warm/dry layer further aloft. However, it is possible that an area of strengthening lower/mid-tropospheric warm advection may become a focus for deepening elevated convective development by late Tuesday night, somewhere across the Ozark Plateau/Mid South vicinity. This may include isolated weak thunderstorm development, but the extent of this potential, and exactly where, remain uncertain, resulting in the maintenance of thunderstorm probabilities below 10 percent. ..Kerr.. 02/03/2025 Read more
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CST Mon Feb 03 2025 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered weak thunderstorm development is possible along the western slopes of the Sierra Nevada, and near Oregon coastal areas, late Tuesday into Tuesday night. Otherwise, the risk for thunderstorms appears negligible across much of the nation. ...Discussion... Downstream of a blocking high, centered to the southeast of the Aleutians, models indicate that large-scale mid-level troughing will be maintained across and offshore of the Pacific Northwest, though an embedded low may reform to the south-southwest of Vancouver Island. To the east of this regime, large-scale mid-level ridging may continue to slowly build across the northern U.S. Great Plains and adjacent Canadian Prairies into the Great Lakes region, while a short wave perturbation digs within northwest flow to its northeast and east. In a separate branch of westerlies, emanating from the southern mid-latitude Pacific, a notable short wave perturbation is forecast to accelerate inland across the California coast and Great Basin/Rockies by 12Z Wednesday, ahead of an inland advancing perturbation within the more prominent cyclonic regime to the north. In lower-levels, it appears that surface troughing will slowly begin to deepen to the immediate lee of the Rockies, as the center of an expansive cold surface ridge shifts from the Canadian Prairies and northern U.S. Great Plains into the Great Lakes, beneath the more strongly confluent mid-level flow. The shallow leading edge of the seasonably cold air mass may stall across parts of the southern Great Plains into Ohio Valley, while advancing offshore of the northern and middle Atlantic Seaboard. At the same time, a southerly return flow of moisture is forecast to develop from parts of the western Gulf Basin into the southern U.S. Great Plains and lower Mississippi Valley. ...California/Sierra Nevada... In advance of the perturbation emanating from the southern mid-latitude Pacific, low/mid-level moistening, differential thermal advection and strong lift, aided by a strengthening upslope flow component, may contribute to weak destabilization along the western slopes of the Sierra Nevada by Tuesday afternoon. Forecast soundings suggest that thermodynamic profiles may become supportive of convection capable of producing lightning by early Tuesday evening, if not earlier. ...Oregon coastal areas... Models indicate that lower/mid-tropospheric cooling will lead to increasing boundary-layer destabilization near coastal areas through the period. As this occurs, some convection, within a broader area of continuing convective development, may deepen through sufficiently cold layers aloft to support occasional lightning. ...Ozark Plateau/Mid South... Beneath low-amplitude large-scale mid-level ridging across the southern Great Plains through the lower Mississippi Valley and Southeast, it appears that low-level moistening and warming will contribute to increasing potential instability. Models indicate that this will generally remain capped by a relatively warm/dry layer further aloft. However, it is possible that an area of strengthening lower/mid-tropospheric warm advection may become a focus for deepening elevated convective development by late Tuesday night, somewhere across the Ozark Plateau/Mid South vicinity. This may include isolated weak thunderstorm development, but the extent of this potential, and exactly where, remain uncertain, resulting in the maintenance of thunderstorm probabilities below 10 percent. ..Kerr.. 02/03/2025 Read more