Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
495 FXUS63 KMKX 131443 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 943 AM CDT Thu Jun 13 2024 .KEY MESSAGES... - Thunderstorms developing near the state line this afternoon, with storms quickly becoming severe as they move south. - Brief cool down Friday and Saturday, but hotter temps build in for Sunday into early next week && .UPDATE... Issued 944 AM CDT Thu Jun 13 2024 Focus remains on severe weather potential this afternoon. The cold front remains to our north, with a weak prefrontal trough south of the boundary. The front will accelerate southward later this morning as a weak shortwave over southern Minnesota moves eastward. There is fairly high confidence that convection will develop along and head of the front between about 1 and 3 PM, quickly turning severe as it moves south. The front is expected to be very close to the state line during this time frame, hence the uncertainty as to whether the severe risk will occur over our far southern CWA, or just to our south. Additional showers are expected behind the front later this afternoon, ending early this evening. Boxell && .SHORT TERM... Issued 405 AM CDT Thu Jun 13 2024 Today through Friday: Showers and storms will move through at least the northern portions of the forecast area this morning, particularly north of I-94. Could be a few stronger storms with some hail this morning given elevated instability in place. There remains uncertainty with storm chances the rest of the day. Latest runs of the HRRR continue to be the most aggressive solutions with storm development early to mid afternoon, with the HRRR keeping the effective boundary farther north than other models. If the boundary is farther south as many models are showing, much of the activity might wind up south of the WI/IL border. Any storms that do fire in the forecast area this afternoon will have the potential to become severe, given plenty of instability and gradually increasing shear. Large hail and damaging winds would the main concerns. Best chance for storms will likely be roughly from Port Washington to Monroe and southeastward. Should be enough sun between rounds of convection for temps into the 80s today. Dry weather is likely to return by early evening, with the front/boundary south of the state by then. High pressure will then build in on Friday, brining mostly sunny skies and cooler temps to the area. DDV && .LONG TERM... Issued 405 AM CDT Thu Jun 13 2024 Friday night through Wednesday: High pressure is expected to gradually shift eastward Friday night and Saturday. Onshore flow will continue to bring mild temperatures and lower humidity to the area. The 500 mb ridge axis shifts eastward over the area on Saturday, and may bring a shortwave trough northeastward along with it. Another shortwave trough may shift northeast through the area Saturday night or Sunday. This may combine with some focused 850 mb warm air advection to bring some elevated showers and thunderstorms at times later Saturday into Sunday. The best focus for this activity appears to be to the northwest of the area during this period, so there may be some uncertainty with how far southeast into the area any of this activity may reach. South to southwest winds in the low levels will continue to bring warm air advection into the area Sunday into next week, with the area likely to be firmly in the warm sector airmass by Monday and lingering into at least the middle of next week. Ensembles and NBM are still confident with general 25th to 75th percentile ranges for high temperatures of upper 80s to lower 90s for Sunday into most of next week. Went in this general range for highs during this period, and could go a little higher if stronger southerly flow develops. Heat index values in the lower to middle 90s appears likely at this time for most of this period. Areas toward Port Washington and Sheboygan, along with locations right along the lakeshore, may get a little onshore flow and some relief from the very warm and humid conditions. The cold front and next decent chances for showers and storms may not push into the region until later in the week. Kept some PoPs for showers and storms in the forecast into next week, though if the warm sector remains in place, any precipitation may be limited to peak daytime heating with popcorn showers and storms developing from reaching convective temperatures. Wood && .AVIATION... Issued 944 AM CDT Thu Jun 13 2024 VFR conditions are expected this morning, with thunderstorms then rapidly developing along a cold front this afternoon. That front is expected to be south of the I-94 corridor when storms develop, with convection then moving southward into Illinois. Impacts to the terminals should be short, but a period of IFR/LIFR and strong gusty winds is certainly possible with any storms. Winds today will initially be from the southwest, turning northwesterly behind the front. Boxell && .MARINE... Issued 405 AM CDT Thu Jun 13 2024 Southwest winds this morning will become west to northwest this afternoon into the evening as a cold front drops through the area. There will be a chance for thunderstorms along and ahead of the front. Winds will be northerly on Friday behind departing low pressure and ahead of an approaching high. Winds will be lighter on Saturday, picking back up out of the south on Sunday as the high pushes east of the area. DDV && .MKX WATCHES/WARNINGS/ADVISORIES... WI...None. LM...None. && $$ Visit us at weather.gov/milwaukee Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/NWSMilwaukee www.twitter.com/NWSMilwaukee www.youtube.com/NWSMilwaukee