437 FXUS61 KCLE 020848 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 448 AM EDT Mon Jun 2 2025 .SYNOPSIS... High pressure over the Ohio Valley today will move to the Mid- Atlantic on Tuesday while continuing to influence the region. A warm front will lift north across the area on Tuesday. A slow moving cold front will progress eastward Wednesday night through Thursday. && .NEAR TERM /THROUGH TUESDAY/... Dry weather with warming temperatures can be expected through the near term. Upper level ridging extends north into Ontario and will expand east across the Great Lakes today. The northwesterly flow aloft has been directing smoke from several fires ongoing in Alberta, Saskatchewan, and Manitoba southeast into northern Plains and Midwest. The smoke has been primarily in the upper levels of the atmosphere and will increase again this afternoon, partially obscuring what would otherwise be clear skies. The smoke is expected to be thick enough that it could suppress temperatures by a degree or two into the 70s in Ohio and upper 60s in NW Pennsylvania. Surface high pressure over the area today will build to the Mid- Atlantic coast on Tuesday with southerly flow and warm advection developing. Temperatures at 850mb reach 15-18C on Tuesday and highs are forecast to climb another 7-10 degrees. The vertically integrated smoke parameter off the HRRR indicates the smoke will be most dense Monday night into Tuesday morning. In addition, a couple parameters are also indicating the smoke may start to descend to lower levels of the atmosphere on Tuesday. Still not expecting reduced surface visibilities but given the potential for the thicker layer and continued whitish tint to the atmosphere have added a mention of haze to the forecast. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... Fair weather is expected Tuesday night as a ridge at the surface and aloft exits slowly E`ward and is accompanied by stabilizing subsidence. Continued low-level warm/moist air advection from the Gulf and southern Gulf Stream, along the western flank of the surface ridge, will contribute to a milder and somewhat muggy night. Lows should reach the upper 50`s to mid 60`s in NW PA and the 60`s to lower 70`s in northern OH. Any lingering Canadian wildfire smoke in our region should exit generally to the north and northeast by daybreak Wednesday courtesy of S`erly to SW`erly winds at/near the surface and SW`erly flow farther aloft. On Wednesday through Thursday night, SW`erly to WSW`erly flow aloft and embedded shortwave disturbances should affect our region as the aforementioned ridge at the surface and aloft continues to exit E`ward and a trough axis aloft approaches from the northern Rockies and north-central United States. At the surface, the trough overspreads our region from the west and a slow-moving cold front should begin to drift SE`ward across essentially the western-third of our CWA Thursday afternoon through Thursday night as multiple lows, attendant to the aforementioned shortwave troughs, move NE`ward along the front. Periodic showers and thunderstorms are expected on Wednesday, but especially during Wednesday night through Thursday night as weak to moderate instability, including elevated CAPE, is released by the following: a low-level return flow of warm/moist air from the Gulf and southern Gulf Stream undergoing isentropic ascent aloft, convergence/moist ascent along surface trough axes and associated with the cyclonic circulations of the frontal surface lows that will accompany the shortwave troughs, convergence/moist ascent along the surface portion and upper-reaches of the cold front. The low-level return flow of warm/moist air from the Gulf and southern Gulf Stream will be associated with unusually- high PWAT`s, which will contribute to showers and thunderstorms capable of producing periods of torrential rainfall. Flash flooding may become a concern as SW`erly to WSW`erly mean mid-level flow of about 20 to 40 knots should exhibit a large component parallel to the cold front and support the development of training, yet progressive showers/storms. WPC has already highlighted NW OH in a marginal risk of excessive rainfall for Wednesday through Wednesday night, while our entire CWA is in a marginal risk of excessive rainfall Thursday through Thursday night. Moderate deep-layer bulk shear may contribute to strong to severe thunderstorm concerns during the afternoon through roughly early evening hours of Wednesday and Thursday, especially if moderate destabilization of the warm/moist sector boundary layer via daytime heating occurs. Greater sunshine and daytime heating on Wednesday are expected to contribute to late afternoon highs reaching the 80`s to 90F in our CWA. Increasing cloud cover will contribute to balmy overnight lows in the 60`s to lower 70`s around daybreak Thursday. Abundant cloud cover and greater coverage of showers/storms are expected to contribute to the following: late afternoon highs reaching the 70`s to lower 80`s on Thursday; overnight lows reaching mainly the upper 50`s to lower 60`s around daybreak Friday. && .LONG TERM /FRIDAY THROUGH SUNDAY/... Cyclonic SW`erly to W`erly flow aloft on Friday through Friday night should veer to NW`erly on Saturday as the aforementioned primary trough axis moves from the Upper Midwest toward New England between daybreak Friday and sunset Saturday evening. At the surface, the aforementioned cold front should continue to drift SE`ward across our region and exit the rest of our CWA by daybreak Saturday as additional surface lows move NE`ward along the front. These lows will be tied to shortwave troughs embedded in the cyclonic flow aloft. On Saturday, a surface ridge should build slowly from the western Great Lakes and vicinity. Additional showers and thunderstorms are expected because the same lifting mechanisms mentioned in the short-term discussion are expected to release at least weak CAPE, including elevated CAPE. PWAT`s will remain unusually-high in the warm/moist sector. Training showers and thunderstorms should remain a concern due to essentially the same reasons mentioned in the short-term discussion. Showers/storms should finally exit generally to the east Saturday morning through early afternoon as the upper-reaches of the cold front exit generally to the southeast. Fair weather is then forecast the rest of Saturday as stabilizing subsidence accompanies the aforementioned surface ridge. The aforementioned cold front is expected to be weak and its passage should result in a minor air mass change, especially with respect to surface air temperatures. Daytime highs are expected to reach the 70`s on Friday and Saturday, respectively. Overnight lows are expected to reach the upper 50`s to lower 60`s around daybreak Saturday. Fair weather is expected Saturday night through Sunday as the aforementioned ridge at the surface and aloft builds from the western Great Lakes and Upper Midwest. This expectation is based on good agreement between the 00Z/Mon runs of the ECMWF/GEM/GFS models and the fact that the often more-reliable ECMWF model and GEM have been depicting this forecast solution for about 24-hours now. N`erly to E`erly surface winds are expected to maintain a somewhat cooler and drier air mass across our region. Overnight lows should reach the 50`s to lower 60`s around daybreak Sunday and be followed by late afternoon highs in the 70`s. && .AVIATION /06Z Monday THROUGH Friday/... VFR conditions will persist through the TAF cycle with high pressure overhead today. We do expect to have some smoke in the upper levels of the atmosphere today from Canadian wildfires but expecting little to no impact to aviation. Light southwesterly winds will become a little more westerly this afternoon with lake breezes expected at CLE(18Z) and ERI(16Z). Winds will back to southwesterly again tonight at 7 knots or less. Outlook...There is a low chance that smoke will reach the lower levels of the atmosphere on Tuesday resulting in some haze and visibilities of 5-6 miles. Periodic showers and thunderstorms with non-VFR are expected Wednesday night through Friday. && .MARINE... Waves are expected to remain 3 feet or less on Lake Erie through this Friday. A ridge will continue to impact Lake Erie, but also exit very slowly E`ward through Tuesday night as the parent high pressure center moves from the WV area to Atlantic waters east of the Delmarva Peninsula by daybreak Wednesday. Primarily S`erly to SW`erly winds around 5 to 15 knots are expected through daybreak Wednesday. On Wednesday through Friday, a trough is expected to overspread Lake Erie generally from the west. A slow-moving cold front associated with this trough should begin to drift SE`ward across Lake Erie Thursday afternoon and become located near the lakeshore from NE OH to western NY by sunset Friday evening. In general, SW`erly winds around 5 to 15 knots should veer to NW`erly with the passage of the cold front. However, wind direction is expected to be erratic at times as multiple lows move NE`ward along the cold front on Thursday through Friday. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. MARINE...None. && $$ SYNOPSIS...10 NEAR TERM...10 SHORT TERM...Jaszka LONG TERM...Jaszka AVIATION...10 MARINE...Jaszka