Area Forecast Discussion
Issued by NWS Cleveland, OH
Issued by NWS Cleveland, OH
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150 FXUS61 KCLE 192335 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 735 PM EDT Fri Jul 19 2024 .SYNOPSIS... A ridge continues to impact northern Ohio and northwest Pennsylvania through Sunday night as the core of the ridge remains draped across the southwestern and eastern Great Lakes region. The ridge begins to exit slowly and generally eastward this Monday through Tuesday as a warm front begins to approach our area from the Tennessee and Ohio Valleys. && .NEAR TERM /THROUGH SATURDAY NIGHT/... 730 PM Update... Scattered clouds should clear near or shortly after sunset and expect clear skies through tonight. Can`t rule out some patchy fog in interior NE OH/NW PA as mentioned in the previous discussion. No changes needed with this update. Previous Discussion... Cyclonic flow aloft, varying between SW`erly and NW`erly, and embedded shortwave disturbances affect our region through Saturday night. Periodic mid/upper-level cloud cover is expected, especially tonight through Saturday night, as mid/upper-level and moist isentropic ascent precedes the axes of the aforementioned shortwave disturbances. At the surface, a ridge continues to impact our CWA as the core of the ridge remains draped across the southwestern and eastern Great Lakes. Fair weather persists as a stabilizing subsidence inversion accompanies the low-level ridge. Overnight lows are expected to reach mainly the 50`s to lower 60`s around daybreak Saturday and mainly the mid 50`s to mid 60`s around daybreak Sunday as cloud breaks, surface dew points near 50F to 55F, and weak or calm surface winds promote efficient radiational cooling during evening hours through daybreak. Localized river valley steam fog is forecast to develop in interior portions of far-NE OH and especially NW PA around daybreak Saturday and Sunday, respectively. Fog will dissipate soon after daybreak via onset of diurnal convective mixing of the boundary layer tapping into drier air just aloft. On Saturday, late afternoon highs are expected to reach the upper 70`s to mid 80`s as diurnal heating/convective mixing of the boundary layer accompany 850 mb temperatures near 12C to 15C. Similar to today, the coolest highs on Saturday are expected over and within several miles of Lake Erie since a very weak synoptic MSLP gradient and daytime heating of surrounding land will once again allow a lake breeze to occur during the late morning through early evening. Given a N`erly synoptic MSLP gradient in our CWA, this lake breeze is expected to exhibit maximum inland extent of at least five to ten miles; similar to today`s lake breeze. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... A mainly quiet short term period is in store across the region as surface high pressure weakens and retreats towards New England through Monday. A moist air mass across the southern CONUS will slowly advect northwards into the region beginning Sunday night. A developing weak upper-level trough across the Missouri Valley may have enough energy to kick off some isolated showers and storms Monday afternoon, although low-level moisture is expected to remain limited, with dew points in the upper 50s to lower 60s. Seasonable highs in the mid-80s are expected for both Sunday and Monday with partly to mostly cloudy skies. && .LONG TERM /TUESDAY THROUGH FRIDAY/... More active weather is anticipated for the long term period as ensembles agree that a moist air mass will remain in place, coupled with increasing amounts of upper-level jet energy. Severe storm chances appear low as widespread cloud cover and poor mid-level lapse rates should limit MLCAPE to generally 1000 J/kg or less. Overall, shear should be fairly marginal, though occasional shortwaves may introduce mid-level southwesterly flow of 25 to perhaps 35 knots at times, particularly Tuesday through Thursday which could result in organized thunderstorm clusters during the afternoon and evening hours. In addition, locally heavy rain will be possible with PWATs in the 90th percentile (1.60 to 1.80 inches) and skinny CAPE profiles. In terms of coverage, scattered to widespread showers and thunderstorms are expected Tuesday through Thursday, particularly during peak heating in the afternoon and evening hours. At some point, surface high pressure is expected to build in from the north across the Great Lakes towards the end of the week and into the weekend, bringing an end to the wet pattern. && .AVIATION /00Z Saturday THROUGH Wednesday/... VFR is expected through the TAF period. Winds will be light and variable overnight with northerly winds 5 to 10 knots expected with the lake breeze from KCLE to KERI Saturday afternoon. Outlook...VFR expected through Monday morning. Isolated to scattered showers/thunderstorms with non-VFR possible Monday afternoon through Wednesday. && .MARINE... A quiet marine period is in store across Lake Erie through the weekend and into early next week with no headlines anticipated. Surface high pressure will gradually weaken through the weekend and be replaced with weak surface troughing which will persist into early next week. For the most part, winds will be 10 knots or less, favoring an onshore component in the afternoon/early evening hours associated with the lake breeze. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. NY...None. MARINE...None. && $$ SYNOPSIS...Jaszka NEAR TERM...Jaszka/Maines SHORT TERM...Kahn LONG TERM...Kahn AVIATION...Maines MARINE...Kahn