Area Forecast Discussion
Issued by NWS Cleveland, OH
Issued by NWS Cleveland, OH
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081 FXUS61 KCLE 292327 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 727 PM EDT Sat Aug 29 2026 .WHAT HAS CHANGED... Introduced a low chance of sprinkles/showers across Lake Erie and a few northern counties tonight. Better chances for precipitation are focused across the northeast on Sunday night. && .KEY MESSAGES... 1) Late season heat and humidity expected to return Tuesday and Wednesday with heat index forecast in the upper 90s. 2) The active storm track will set up across the Central and eastern Great Lakes from Sunday night through Wednesday night, bringing a chance of thunderstorms to mainly Northeast Ohio and Northwest Pennsylvania. Chances of thunderstorms will expand inland on Thursday as a cold front pushes south. && .DISCUSSION... KEY MESSAGE 1... A warm front will lift north Sunday night ahead of the upper level ridge which will expand into the region. High temperatures will trend 3-5 degrees warmer on Monday then continue to creep up Tuesday and Wednesday as the upper level ridge becomes firmly established. Temperatures at 850mb will range from 20-23C with highs in northern Ohio in the lower 90s, with a few sites in NW Ohio reaching the mid 90s. This is 10 or more degrees above normal for the beginning of September. Dewpoints also increase during this time frame into the upper 60s which will push heat index values solidly into the mid and upper 90s Tuesday and potentially approaching 100 across the western half of the area on Wednesday. (Heat index will be slightly cooler in the lower 90s in NW PA). It is possible that a portion of the area could need a Heat Advisory by Tuesday or Wednesday but will also depend on if we have any thunderstorms those days. In general confidence is increase that there will be a heat threat early this week but some adjustment to temperatures is still possible based on clouds and coverage of any precipitation. KEY MESSAGE 2... High pressure with a dry airmass is in place across the region today before building to the Mid-Atlantic region overnight. Meanwhile mid-level moisture will be on the increase overnight as shortwave energy traverses the Great Lakes Region. While low levels are generally expected to remain dry, models do not have a very good handle on the southern extent of showers in Illinois this afternoon. While the precipitation across the western Great Lakes is largely expected to dissipate, expect sufficient moistening aloft to include a 20 percent chance of a shower across Lake Erie or a few of our northern counties overnight, which could just be in the form of sprinkles. Better chances for precipitation come Sunday night as convection over lower Michigan favors a southeast trajectory towards Northwest Pennsylvania ahead of the building ridge. The warm front will bisect our northeastern counties Sunday night before lifting north on Monday. There is some potential for locally heavy rain across mainly Northwest Pennsylvania on Sunday night with thunderstorms. After that the ridge is expected to expand north on Monday. This will hopefully place the active storm track from the Upper Great Lakes towards New York but we will have to monitor the strength of the building ridge on Tuesday and Wednesday. Models generally in good agreement of 700mb temperatures reaching 10C with a capping inversion developing overhead. The next stronger piece of energy to round or break down the upper level ridge is expected Wednesday night, pushing a weak cold front south into the area by Thursday. We will have to monitor the eventual break down of the upper level ridge which could lead to strong thunderstorms for a portion of the area on Wednesday night or Thursday. && .AVIATION /00Z Sunday THROUGH Thursday/... BKN-OVC FL200 continues, added TEMPO 5SM -SHRA with a warm front for 2hr durations after 04Z west to east. Winds less than 12kts. SCT-BKN cumulus develops with BKN-OVC mid level deck Sunday. More showers possible after 18Z Sunday will need to be examined for next set of TAFs. TSRA potential on the lower side Sunday but non-zero. Outlook...Non-VFR possible Sunday night into Monday with showers and thunderstorms and again on Wednesday. && .MARINE... Marine weather conditions will be quiet through the weekend. High pressure is over the eastern Great Lakes today and will drift eastward on Sunday. A warm front will lift northward across Lake Erie by Sunday night and bring scattered showers and storms. Winds will generally be from the south to southwest 5 to 15 knots today through middle of next week and waves of 1 to 2 feet. Marine headlines are not expected on the lake for the next several days. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. MARINE...None. && $$ DISCUSSION...10 AVIATION...26 MARINE...77