FXUS61 KCLE 062257 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 657 PM EDT Sat Jul 6 2024 .SYNOPSIS... High pressure will build across the region tonight and persist through Monday. Low pressure will extend a weak cold front east across the area on Tuesday. && .NEAR TERM /THROUGH SUNDAY NIGHT/... 6:50 PM Update... Added some patchy fog for tonight across the outer edges of our forecast area, otherwise no changes were made to the forecast. Previous Discussion... Quiet and seasonable weather is expected for the near term period as high pressure builds across the area tonight and persists through Sunday night. For the remainder of today, there is still the potential for an isolated shower or two across NW PA, though confidence remains low given limited low and mid- level moisture. For Sunday, expecting more diurnal cu to develop in the late morning/afternoon, though perhaps slightly less coverage than today as temperatures rise into the low to mid-80s. A lake breeze is expected to develop as the MSLP gradient remains weak. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... SW'erly flow aloft is expected to reside over our CWA on Monday as a ridge at the surface and aloft exits E'ward. A weak synoptic MSLP gradient and sufficient daytime heating of land surrounding ~73F Lake Erie are expected to allow a lake breeze to occur within several miles of the lake during the late morning through early evening hours. The stabilizing lake breeze and stabilizing subsidence associated with the ridge will allow fair weather to impact our entire CWA. Late afternoon highs are forecast to reach the lower 80's to lower 90's, with the coolest readings expected over/near Lake Erie. Cyclonic SW'erly to W'erly flow aloft and embedded shortwave disturbances affect our CWA on Monday night through Tuesday night. At the surface, troughing becomes established across our area. A warm front is expected to sweep NE'ward through our region Monday night and usher-in a warmer/slightly more-humid air mass originating over the Gulf of Mexico and supportive of periods of heavy rainfall as PWAT values rise to unusually-high values per forecast model data and the climatological data from the four upper-air stations closest to our CWA. Moist isentropic ascent along the upper-reaches of the warm front should release sufficient elevated CAPE to generate isolated showers/thunderstorms after midnight, especially over/near NW OH and far-western Lake Erie. Despite moderate deep layer bulk shear, the elevated nature of storms and lack of steep mid-level lapse rates are expected to prevent storms from becoming severe. Overnight lows should reach mainly the mid 60's to lower 70's around daybreak Tuesday. Peeks of sunshine and daytime heating on Tuesday are forecast to allow late afternoon highs to reach the upper 70's to upper 80's. Isolated to scattered showers/thunderstorms are expected as low-level convergence along shortwave disturbance- related surface trough axes interact with weak to moderate warm/moist sector boundary layer CAPE amidst moderate to strong deep layer bulk shear. A continued lack of steep mid-level lapse rates should prevent severe hail, but strong to severe thunderstorms with strong to damaging convective gusts are possible during the afternoon through early evening as diurnal convective mixing of the boundary layer yields steep low-level lapse rates and contributes to the formation of sizable DCAPE. A weak cold front is still poised to sweep SE'ward through our region Tuesday night and usher-in a slightly cooler/less-humid air mass associated with a surface ridge that will build from the northern Great Lakes and vicinity. However, surface dew points are forecast to remain in the 60's. Isolated to scattered showers/thunderstorms should occur along the cold front and pre-front surface trough axes attendant to shortwave disturbances as these lifting mechanisms encounter weak to perhaps moderate boundary layer CAPE amidst continued moderate to strong deep layer bulk shear in the warm/moist sector. However, slight boundary layer stabilization via nocturnal cooling should allow any lingering potential for damaging convective gusts to end by midnight. Overnight lows should reach mainly the 60's around daybreak Wednesday. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... Forecast confidence is low during this period due, in part to uncertainty regarding the evolution of what will become the remnant low of Tropical Cyclone Beryl. Cyclonic SW'erly to W'erly flow aloft and embedded shortwave disturbances should continue to impact our CWA as a longwave trough remains entrenched over/near the northern/central Great Plains and the core of mid/upper-level ridging resides well-downstream of our region, over/near the Atlantic Ocean offshore the northeastern and Mid-Atlantic states. At the surface, the aforementioned front should drift SE'ward toward the OH River on Wednesday and then waver near the river on Thursday through Saturday as Beryl's remnant low moves along the front from near the Mid MS Valley toward the northeastern U.S. and other surface lows attendant to the aforementioned shortwave disturbances follow suit. Simultaneously, the aforementioned surface high should continue to build slowly from the northern Great Lakes and vicinity. Isentropic ascent along the upper-reaches of the front and preceding shortwave trough axes, and low-level convergence/attendant ascent associated with the cyclonic circulations of the frontal lows should interact with sufficient moisture and instability, including elevated CAPE, to trigger periods of showers/thunderstorms, especially each afternoon through early evening, when MUCAPE will be maximized via peeks of sunshine and daytime heating. Daily afternoon highs are expected to reach mainly the lower to mid 80's on Wednesday through Saturday. Overnight lows should reach the 60's to lower 70's Wednesday night through Friday night, respectively. && .AVIATION /18Z Saturday THROUGH Thursday/... VFR expected to continue through the TAF period as high pressure builds in tonight. Afternoon cumulus clouds should dissipate over the next couple hours. Patchy fog could develop for some inland locations late tonight into early Sunday morning but confidence wasn't high enough to add to any TAF sites. Scattered afternoon cumulus clouds of 3-5kft are expected again Sunday. Winds will decrease to less than 5 knots overnight, remaining light into Sunday. A lake breeze is expected to develop by late Sunday morning/early afternoon at CLE/ERI, shifting winds towards the northwest, 5 to 8 knots. Outlook...Non-VFR possible in isolated to scattered showers and thunderstorms Tuesday through Thursday. && .MARINE... Winds are expected to remain around 5 to 15 knots the rest of today through this Thursday. As a result, waves are expected to remain 3 feet or less. SW'erly to W'erly winds accompanying a lingering trough over Lake Erie become variable tonight through Monday as a ridge builds from the west. These variable winds will trend onshore during the late morning through early evening hours of Sunday and Monday, when lake breeze development is expected. E'erly to SE'erly winds develop Monday evening and then veer to S'erly to SW'erly overnight due to the NE'ward passage of a warm front. S'erly to SW'erly winds persist over Lake Erie on Tuesday and then veer toward NW'erly Tuesday night, when a weak cold front is expected to sweep SE'ward across the lake and be followed by a ridge building from the northern Great Lakes and vicinity. Variable winds are expected on Wednesday, when another lake breeze should develop during the late morning through early evening. Winds should then become E'erly to NE'erly over Lake Erie Wednesday night through Thursday as the aforementioned front settles near the OH River, Tropical Cyclone Beryl's remnant low weakens/moves along the front from the Mid MS Valley toward the Mid OH Valley, and interacts with the aforementioned ridge that should continue to build from the northern Great Lakes and vicinity. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. NY...None. MARINE...None. && $$ SYNOPSIS...Kahn NEAR TERM...Kahn/Saunders SHORT TERM...Jaszka LONG TERM...Jaszka AVIATION...Saunders MARINE...Jaszka