Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Aug 01 2023 19:51:26 ACUS01 KWNS 011951 SWODY1 SPC AC 011949 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0249 PM CDT Tue Aug 01 2023 Valid 012000Z - 021200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH EARLY TONIGHT FOR PARTS OF THE NORTHERN PLAINS AND CENTRAL HIGH PLAINS... ....SUMMARY... Severe-thunderstorm gusts are most probable over parts of the central High Plains and much of North Dakota to northwestern Minnesota, along with at least isolated large hail. ....20Z Update... Overall forecast remains on track with no changes needed to the existing outlook. Late afternoon thunderstorm development is still anticipated over ND, both along the front in north-central ND and in the MT/ND border vicinity. The environmental conditions still support supercells capable of large hail and damaging gusts. Additionally, ongoing thunderstorms across central CO as are still expected to grow upscale later this evening, with an attendant threat for severe outflow gusts and isolated large hail. ...Mosier.. 08/01/2023 ..PREV DISCUSSION... /ISSUED 1119 AM CDT Tue Aug 01 2023/ ....Northern Plains through tonight... A midlevel shortwave trough is cresting the midlevel ridge and will continue east-southeastward over southern SK/AB toward ON, as an associated weak cold front moves southeastward into ND. Convection is ongoing in a few clusters near the ND/MT/SK border and northwest MN along the north edge of the unstable warm sector. Some form of these storms could persist through the afternoon, though the main severe threat is expected to be additional development along the front and/or outflow boundaries by mid-late afternoon. Steep midlevel lapse rates, boundary-layer dewpoints in the 65-70 F range and daytime heating will boost MLCAPE to 2000 J/kg or greater as convective inhibition weakens. Low-level flow will be weak beneath moderately strong mid-upper westerly flow, resulting in small low-level hodographs and longer hodographs above about 4 km AGL. This environment will support a mix of multicell clusters and some supercells capable of producing large hail and damaging winds as convection spreads southeastward late this afternoon into early tonight. ....Central High Plains this evening... Within the monsoonal moisture plume, convectively-enhanced waves will move slowly eastward from UT/WY/CO toward NE. Thunderstorms are expected to form later this afternoon near and just east of the Front Range in a weak upslope flow regime in CO, and convection will subsequently grow upscale into a cluster or two across northeast CO and vicinity this evening. Moderate buoyancy and relatively weak vertical shear will mainly favor multicell clusters capable of producing occasional severe outflow gusts and isolated large hail. ....MO area through tonight... Elevated convection persists late this morning over central MO in a low-level warm advection regime, though this convection is expected to diminish as warm advection weakens this afternoon. There will be a low chance for afternoon storm development on the west edge of the cloud debris and northeast edge of the hot surface temperatures/deeper mixing near the KS/MO border, with a conditional wind/hail threat. The more probable scenario will be for renewed thunderstorm development tonight as warm advection increases again on the nose of a southwesterly low-level jet. The overnight storms will be capable of producing isolated large hail and possibly a few strong outflow gusts. ....Carolinas to FL this afternoon... Surface heating with lingering low-level moisture, beneath midlevel drying, will result in moderate destabilization across the eastern Carolinas, where isolated thunderstorms are expected this afternoon along the sea breeze and subtle terrain influences inland. Buoyancy will be larger to the south (>2500 J/kg MLCAPE from southeast GA southward) where widely scattered afternoon thunderstorms are expected mainly inland from the west coast sea breeze. The moderate buoyancy, DCAPE near 1000 J/kg, and some modest enhancement to vertical shear from north FL northward will support a low-end threat for strong/damaging downburst winds. $$ = = = To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .