SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1151 AM CDT Mon Jun 28 2021 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM WI AND MI INTO NORTHERN IL/IN/OH... ...SUMMARY... Isolated severe thunderstorms are possible across portions of the Upper Midwest and Upper Great Lakes Region on Tuesday. ...Great Lakes Vicinity... An upper shortwave trough will migrate eastward across the Great Lakes on Tuesday. West/southwesterly midlevel flow will increase in response, with 30-40 kt forecast around 700-500 mb over WI/MI and northern portions of IL/IN/OH. Cooling aloft will result in modest midlevel lapse rates across parts of WI/Upper MI. Aided by surface dewpoints in the low to mid 60s F, weak to moderate instability is forecast amid 25-35 kt effective shear. This could support briefly organized cells/bowing segments capable of strong wind gusts. Further south toward northern IL/IN/OH and Lower MI, stronger heating and dewpoints in the upper 60s to near 70 F will result in stronger instability. However, midlevel lapse rates will remain poor and effective shear more marginal compared to further north/northwest. Nevertheless, high PW values amid adequate shear/instability and steeper low level lapse rates could support sporadic strong/locally damaging wind gusts through early evening. ...AZ... Isolated thunderstorms are expected to develop near the higher terrain of the Mogollon Rim during the afternoon/evening amid increasing midlevel moisture. Weak shear and modest instability/lapse rates will limit longevity of more intense updrafts, but a well-mixed boundary layer with inverted-v sub-cloud thermodynamic profiles suggest strong downburst winds are possible. Storm coverage is expected to remain sparse and in the absence of stronger shear/instability, the overall threat limited, precluding severe probabilities at this time. ..Leitman.. 06/28/2021 Read more LIVE: spc.noaa.gov
http://dlvr.it/S2dj56
