572 FXUS61 KCLE 051040 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 640 AM EDT Sun Jul 5 2020 .SYNOPSIS... High pressure will persist over the area through midweek, weakening by Wednesday. A weak cold front will move across the area Tuesday night into Wednesday before a stronger cold front pushes through towards the end of the week on Friday. && .NEAR TERM /THROUGH MONDAY/... Light, patchy fog is scattered across the are this morning, but is not expected to linger long after sunrise. Temperatures are currently in the low to mid 60's across the area but will quickly begin to rise today with clear skies across the area providing ample sunshine. The remainder of the near term forecast is still on track through Monday. Previous Discussion... Today, the upper level ridge will persist over the area keeping a rather dry airmass in place. Temperatures will begin to increase today with highs in the mid 90's with cooler temperatures along the lakeshore. No precipitation is expected and humidity values will remain low for today as the bulk of moisture remains on the periphery of the forecast area. Overnight low temperatures are expected to remain a bit warmer than previous nights with temperatures only dropping to the upper 60's to low 70's. On Monday, similar conditions will persist with temperatures again increasing to have high temperatures in the mid 90's with heat indices only a few degrees higher as humidity values again remain low with dew point temperatures remaining in the low 60's. Hi-Res models are hinting at isolated showers in NW OH on Monday, however confidence is low so kept chance PoPs out of this forecast update. If these do occur, they will most likely occur along the lake breeze boundary during the diurnal cycle with mesoscale ascent playing a large role in storm development. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... Broad upper level ridge will remain across the area this week with above normal temperatures continuing. Forecast high temperatures are expected to be in the low to mid 90s across the entire area Tuesday and Wednesday. Dewpoints have been on the low side but will trend up through mid-week as a shortwave and associated weak trough moves across the upper Great Lakes on Tuesday. As dewpoints creep up into the mid and upper 60s, we will begin to see scattered thunderstorms return to the area and heat index values reach the upper 90s across parts of Ohio. By Tuesday a few thunderstorms are possible across NW Ohio and along the lake breeze in NE Ohio. By Wednesday, storms will be possible along the lake breeze again, then drifting to the south through the afternoon. Warm mid levels will continue to limit coverage of storms so will continue with just a chance in the forecast, but mesoscale boundaries like lake breezes and outflow boundaries will be sufficient for some storm development. Expecting coverage to be low enough that they only provide localized respite from the heat. After several days of building heat, low temperatures will struggle to dip below 70 degrees. && .LONG TERM /THURSDAY THROUGH SATURDAY/... The heat is expected to peak late this week, before temperatures drop back closer to normal over the weekend. ECMWF MOS guidance places the hottest day of the week on Thursday for most sites with the ridge firmly overhead. Heat index values will be near Heat Advisory criteria across much of northern Ohio with highest values across the west. Heat stress will become increasingly concerning through the week with repeated days of heat and sun combined with warm overnight lows that will provide little relief. Models continue to show the upper level ridge breaking down Friday into Saturday as a series of troughs move out of the northern Plains across the Midwest. Friday is still expected to be hot with increasing humidity ahead of the front. Best chances of showers and thunderstorms this week will be late Friday into Saturday. && .AVIATION /12Z Sunday THROUGH Thursday/... Currently, scattered fog/haze has resulted in reduced visibility at multiple TAF sites across the area. Visibilities at CLE, TOL, and CAK continue to bounce between VFR and MVFR, with TOL occasionally reaching IFR conditions. Kept tempos for MVFR visibilities through 12Z with expectation that sunrise will aid in reducing coverage of fog and increasing wind speed to allow the air to mix a bit. For the remainder of the TAF period, VFR conditions will persist as an upper level ridge continues to dominate the region. The day will begin with light and variable winds. A lake breeze will set up allowing winds to shift to north to northeasterly at 5 to 10 knots for sites along the lakeshore this afternoon. Outlook...Non-VFR in isolated thunderstorms on Tuesday and scattered thunderstorms on Wednesday. && .MARINE... A light wind regime will continue on Lake Erie with generally good boating conditions persisting through the week. Most afternoon will feature a lake breeze of 5 to 15 knots. Isolated thunderstorms will be possible from Tuesday through Thursday time frame with greater coverage of thunderstorms possible along a cold front Friday night. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. MARINE...None. && $$ SYNOPSIS...Campbell NEAR TERM...Campbell SHORT TERM...KEC LONG TERM...KEC AVIATION...Campbell MARINE...KEC