Subj : DAY1 3/5 RISK AREA UPDAT To : All From : Mike Powell Date : Thu Jul 02 2026 22:32:00 ACUS01 KWNS 022001 SWODY1 SPC AC 022000 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Thu Jul 02 2026 Valid 022000Z - 031200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN SOUTH DAKOTA INTO FAR SOUTHWEST MINNESOTA AND EXTREME NORTHWEST IOWA... ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE NORTHERN HIGH PLAINS TO THE GREAT LAKES...WESTERN KANSAS...AND PARTS OF THE TENNESSEE VALLEY... ....SUMMARY... Scattered severe storms are still possible from the northern Plains into the Midwest and Great Lakes regions today into tonight, as well as across the southern Appalachians and Tennessee Valley this afternoon and early evening. ....20Z Update... Much of the previous forecast remains generally on track, especially for portions of the central High Plains, the TN Valley, and northern New England. However, appreciable uncertainty still exists regarding the potential for focused corridors of severe across much of the northern Plains into the Great Lakes. Relatively robust supercell evolution has occurred along mesoscale surface baroclinic boundaries, amid generally weak upper-level support, to support instances of 2-3 inch diameter hail over central/eastern SD, as well as instances of brief and modest rotation with storms over northeastern IA. Please see MCDs 1440-1441 for short-term details of convective evolution. However, these storms are moving roughly normal to boundary orientation, putting the duration of higher-end severe into question. At least for portions of the Upper Midwest though, there is a modest signal of an MCS traversing a baroclinic boundary along the WI/IL border for multiple hours. A locally greater concentration of damaging gusts could accompany this activity through the afternoon, though confidence in this scenario is not overly high either. Many of the ongoing storms (especially over SD) are occurring over portions of the open warm sector relatively early in the diurnal heating cycle, casting uncertainty regarding the impacts the ongoing storms will have on later afternoon initiation and evolution along other mesoscale boundaries. As such, prudence was exercised in favor of making only minor changes to the outlook to reflect the latest guidance consensus. ...Squitieri.. 07/02/2026 ..PREV DISCUSSION... /ISSUED 1124 AM CDT Thu Jul 02 2026/ ....SD to WI... Morning water vapor imagery shows several weak and/or convectively induced shortwave troughs moving across the northern Plains into the Upper Midwest. This area will have widespread marginal to moderate afternoon CAPE and dewpoints in the 60s to lower 70s. This leads to a forecast of a large area of potential thunderstorm development, but with weak/nebulous forcing and general height-rises aloft. As such, the overall confidence in this forecast is not very high. Storms are likely to focus along a boundary currently evident from southern SD into central IA. Convection currently developing in northern IA near the boundary should continue to intensify through the afternoon and track into southern WI/northern IL with a severe wind/hail threat. Other intense thunderstorm clusters are expected to develop along the SD/NE portion of the boundary by mid/late afternoon, also with a risk of large hail and damaging wind gusts. ....Western KS... Full sunshine and dewpoints in the 60s will lead to a region of strong instability over western KS this afternoon. Most CAM solutions suggest at least isolated thunderstorms form along the KS/CO border and spread slowly eastward during the evening. A deeply mixed boundary layer and sufficient CAPE suggest a risk of damaging wind gusts in the strongest cells. ....TN Valley/Southern Appalachians... A widespread very moist and unstable air mass is present today across this region, with full sunshine leading to steep low-level lapse rates and MLCAPE values over 4000 J/kg. Weak forcing under an upper ridge limits confidence in timing/location of storms. However, widely scattered thunderstorm development should eventually result in merging outflows and the risk of gusty/damaging winds this afternoon and early evening across the region. $$ --- Scorpio BBS * Origin: Capitol City Online (618:250/10) .