568 FXUS61 KCLE 080603 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 203 AM EDT Tue Jul 8 2025 .SYNOPSIS... A cold front continues to sweep southeastward across northern Ohio and northwest Pennsylvania through this early evening. Behind the front, a ridge attempts to build from eastern Canada through this Friday. Simultaneously, the aforementioned front will waver in a north-south manner between Lake Erie and the Mid to Upper Ohio Valley as multiple weak lows move generally eastward along the front. && .NEAR TERM /THROUGH TONIGHT/... 7:55 PM Update... The cold front has passed through the forecast area with showers and thunderstorms essentially over. A few light, lingering showers may be possible through about midnight. Otherwise, so minor changes to the forecast were made to account for greater cloud coverage tonight. Previous Discussion... WSW`erly to W`erly flow aloft and embedded shortwave disturbances affect our region through daybreak Wednesday. At the surface, a cold front augmented by convective outflow appeared to be located near a Jamestown, NY to Warren, OH to Polk, OH to Kenton, OH line at 3:25 PM EDT. This front will continue to drift SE`ward and should exit our CWA by 7 PM EDT this evening. Behind the front, a ridge builds from northern ON through daybreak Wednesday. Ahead of the cold front, daytime heating in the warm/moist sector has allowed for the development of moderate boundary layer CAPE amidst moderate effective bulk shear and unusually-high PWAT`s courtesy of a low-level return flow of very moist air from the Gulf. Diurnal convective mixing of the boundary layer has yielded steep low- level lapse rates below somewhat drier mid-level air, which in turn, have yielded moderate DCAPE. Therefore, organized showers/storms capable of producing periods of heavy rainfall and a few thunderstorms capable of producing straight-line wind damage via wet downbursts remain a concern through this early evening, especially farther to the southeast in our CWA, along and ahead of the surface front. Isolated flash flooding also remains a concern since ~20 knot WSW`erly mean mid-level flow will exhibit a large component parallel to the front, which will allow training, slow-moving showers/storms to develop along the front. Following the surface cold front passage, isolated multicell showers/storms will remain possible for several more hours as low-level convergence/moist ascent along the upper- reaches of the front release weak, elevated CAPE amidst continued moderate effective bulk shear. Fair weather is expected to return to our entire CWA by midnight tonight and then persist through daybreak Wednesday courtesy of stabilizing subsidence accompanying the aforementioned surface ridge. Behind the cold front, weak low-level CAA and partial clearing will allow lows to reach mainly the 60`s around daybreak Wednesday. Easing surface winds in response to a weakening MSLP gradient accompanying the ridge and residual low-level moisture from recent rainfall should contribute to patchy radiation fog development during the predawn hours of Tuesday morning, especially inland from ~73F Lake Erie. Any fog is expected to dissipate soon after daybreak Tuesday morning, with the onset of diurnal convective mixing of the boundary layer, which will also tap into somewhat drier air farther aloft. Peeks of sunshine and daytime heating are expected to allow highs to reach the upper 70`s to lower 80`s in NW PA and the upper 70`s to mid 80`s in northern OH late Tuesday afternoon. Sufficient daytime heating of land surrounding relatively-cold Lake Erie and a weak synoptic MSLP gradient will allow a lake breeze to form and penetrate up to several miles inland during the late morning through early evening. The coolest highs are expected within the lake breeze. Intervals of clear sky, light surface winds, and a somewhat drier low-level air mass are expected to promote efficient radiational cooling Tuesday evening through daybreak Wednesday, especially in NW PA, where lows should reach the upper 50`s to mid 60`s. In northern OH, lows should reach the lower 60`s to lower 70`s around daybreak Wednesday. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... W`erly flow aloft and embedded shortwave disturbances should continue to affect our region during this period. At the surface, the aforementioned front should waver in a north-south manner between Lake Erie and the Mid to Upper OH Valley as multiple, weak frontal lows move generally E`ward and accompany the shortwave troughs. Each time the front wavers generally S`ward, the aforementioned surface ridge will rebuild from eastern Canada. The wavering front and a daily Lake Erie lake breeze front are expected to act as foci for the development of scattered showers/thunderstorms, amidst a moist low-level air mass (e.g. surface dew points in the 60`s to 70F) and weak to moderate CAPE belonging to parcels rooted in the low-level atmospheric column. Daytime heating is expected to allow CAPE and convection coverage to be greatest each afternoon through early evening. Modest deep-layer bulk shear should support the development of loosely-organized multicell showers and storms. The aforementioned thermodynamics and kinematics may contribute to some storms becoming strong to severe, especially each afternoon through early evening. Modest and W`erly mean mid- level flow should be roughly parallel to portions of the Lake Erie lake breeze front and synoptic front, which should support slow- moving, training convection and perhaps contribute to localized flash flooding concerns. Near- normal highs in the lower to mid 80`s are expected during the afternoon of Wednesday and Thursday, respectively. Overnight lows mainly in the 60`s to lower 70`s are expected around daybreak on Thursday and Friday, respectively. && .LONG TERM /FRIDAY THROUGH MONDAY/... W`erly flow aloft and embedded shortwave disturbances should continue to affect our region through Monday. At the surface, a somewhat stronger surface low preceding one of the shortwave trough axes should develop generally NE`ward from the north- central United States toward Hudson Bay. This should allow a warm front to sweep NE`ward through our region Friday night through Saturday morning. The warm front will allow a warmer and more-humid air mass originating over the Gulf to overspread our region. The low`s trailing cold front should remain west of our region and we should remain within the warm/moist sector through Monday. Daily afternoon highs should reach the 80`s to near 90F. Daily lows should reach mainly the lower 60`s to mid 70`s around daybreak Saturday, Sunday, and Monday. Periodic showers and thunderstorms are expected as the following lifting mechanisms interact with sufficient low-level moisture and release sufficient CAPE, including elevated CAPE: isentropic ascent along the upper-reaches of the warm front and preceding shortwave trough axes; convergence/ascent along the surface warm front, surface trough axes accompanying the shortwave troughs, and a daily Lake Erie lake breeze front. Shower/storm coverage and intensity should tend to be greatest each afternoon through early evening, as the moist boundary layer destabilizes via daytime heating. Primarily moderate deep- layer bulk shear may contribute to daily potential for some strong to severe storms. Sizable PWAT values will likely contribute to showers/storms producing periods of heavy rainfall. && .AVIATION /06Z Tuesday THROUGH Saturday/... Showers have largely ended across the area but a little light rain or drizzle remains possible at ERI through 08Z. Otherwise, high pressure will build in from the north today with subsidence increasing. Moist low level conditions remain with a mix of MVFR and IFR ceilings across the area except towards TOL where skies have cleared out. Ceilings are largely expected to lower to IFR over the next several hours and can expect to see visibilities at most inland terminals lower into the MVFR range. There is uncertainty in how low ceilings and visibilites will get towards dawn, but could see low IFR ceilings at CAK/MFD/YNG and also IFR visibilities which could drop to a half mile or less in the 09-12Z window. Locations that clear out like TOL/FDY could also see IFR visibilities as temperatures cool late tonight. CLE and ERI are likely to see less of an impact with potential for a couple hours of MVFR visibilities. On Tuesday morning, visibilities are expected to rapidly improve after 12Z and ceilings are likely to lift to MVFR for much of the morning before scattering out for the afternoon. Light north winds may go calm overnight then be out of the west or northwest on Tuesday. Winds will go calm or develop out of the southeast after 00Z Wednesday. Outlook...Non-VFR will be possible with scattered showers and thunderstorms Wednesday through Saturday, with the best chance during the afternoon. && .MARINE... Northerly winds to around 10 knots and waves of 1 to 2 feet in nearshore zones are expected as a cold front pushes south of Lake Erie this afternoon and tonight. Winds will likely become more light and variable by Tuesday afternoon as high pressure builds into the region and expect similar flow with sustained winds under 10 knots through Wednesday. Flow will become more east/southeasterly Thursday and Friday, but winds will remain below 10 knots. Lake breezes may result in periods of onshore flow and possibly a bit of choppiness in nearshore zones during the afternoon Tuesday through the end of the week. Marine conditions will remain relatively calm over the next several days, although afternoon showers and thunderstorms are possible Wednesday through Saturday. Winds/waves may be higher in thunderstorms. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. MARINE...None. && $$ SYNOPSIS...Jaszka NEAR TERM...Jaszka/Saunders SHORT TERM...Jaszka LONG TERM...Jaszka AVIATION...10 MARINE...15