


Area Forecast Discussion
Issued by NWS Cleveland, OH
Issued by NWS Cleveland, OH
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800 FXUS61 KCLE 200014 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 814 PM EDT Tue Aug 19 2025 .SYNOPSIS... Low pressure will cross Lake Erie and northern Ohio this evening, dragging a cold front across the region tonight. The front will slow over the Appalachians Wednesday into Wednesday night before Canadian high pressure builds in from the north by Thursday and Friday. Another cold front will move through Saturday. && .NEAR TERM /THROUGH WEDNESDAY NIGHT/... Showers and thunderstorms this evening have been efficient rain producers. Activity is waning in intensity as it pushes east away from the reservoir of better instability which remains focused across western Ohio. Storm strength has been hampered by weak mid level lapse rates and peak gusts this evening have been around 35 knots. While additional thunderstorms may continue to develop along the cold front which extends from near Sandusky to Findlay, potential for any severe thunderstorms has decreased. Previous discussion...The focus for this afternoon and evening will be on scattered convection developing ahead of the cold front, bringing the potential for localized strong winds and heavy rainfall. The first wave of showers and embedded thunder, which was driven by warm air advection and isentropic ascent E and NE of the retreating warm front, has weakened over NE Ohio and NW PA. The airmass is recovering in the wake of this earlier round, where breaks of sunshine have allowed surface temperatures to warm into the mid 80s in much of NW and north central Ohio. This combined with dew points that rapidly increased into the upper 60s/low 70s in the warm sector has allowed MLCAPE values to reach 500-1000 J/KG in NW and north central Ohio. There is no capping in place, so as low-level convergence and frontogenetic forcing continue to increase aided by the right entrance of a 50-65 knot H3 jet streak crossing central Michigan, convection will continue to expand in coverage ahead of the front through the evening. HREF ensembles and individual CAM members have struggled all day with the timing, evolution, and placement of the convection, but the latest runs seem to be initializing slightly better based on current radar trends. Expect the broken line of showers and thunderstorms developing from western Lake Erie to Wyandot County to continue to fill in somewhat as it moves east this evening, and this should be the main show. The marginal CAPE mentioned above combined with effective bulk shear of around 30 knots near the front will support the SWODY1 Marginal Risk for severe weather, but this threat will be very isolated, with wind being the main threat. Given the surface low and associated enhanced vorticity passing overhead, cannot entirely rule out an isolated, brief spin up tornado either, but this is lower confidence compared to the gusty winds. Locally heavy rainfall will accompany any convection given PWATs in the 1.75 to 2.00 inch range. The bulk of the convection will be east and southeast of the region by 00Z, but periodic showers will hang back over the area, mainly along and east of I-77, much of the night as the cold frontal progression slows over the Appalachians combined with continued upper jet support as the mid/upper trough axis crosses the southern Great Lakes, so increased POPs over eastern areas tonight. The best mid/upper forcing departs Wednesday, but the cold front will become quasi- stationary over the Appalachians through Wednesday night in response to Hurricane Erin lifting north offshore of the NC Outer Banks. This will cause an inverted surface trough and low-level moisture to drift westward into our eastern CWA Wednesday and Wednesday night, so kept POPs slightly higher than raw NBM. Most areas will not see much rain Wednesday and Wednesday night (certainly no washouts), but elevated cloud cover and scattered off and on showers will be around, slightly delaying the transition to the beautiful upcoming weather. Highs will cool into the mid/upper 70s Wednesday, but it will still be rather muggy. Lows tonight will stay in the mid 60s to around 70, but cooler and drier air will start to move in Wednesday night thanks to Canadian high pressure over the northern Great Lakes finally starting to build south, so expect lows to fall into the low/mid 60s Wednesday night. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... The aforementioned large surface ridge of Canadian high pressure will slowly build from the northern Great Lakes through the central and southern Great Lakes Thursday through Friday night. This will finally push the old frontal boundary farther south, so a few lingering showers in eastern Ohio and western PA Thursday morning should end by afternoon as the drier air and subsidence work into the region. The Canadian high combined with mid/upper troughing over the eastern Great Lakes and New England will bring refreshingly cooler and less humid air to the region, with highs in the mid/upper 70s Thursday and upper 70s/low 80s Friday. Lows both Thursday and Friday nights will fall into the upper 50s/low 60s, with some mid 50s in interior NE Ohio and NW PA. && .LONG TERM /SATURDAY THROUGH TUESDAY/... The cooler and less humid pattern will turn even cooler for the extended range as a deep mid/upper trough digs from the northern Plains and Upper Midwest Saturday through the Great Lakes Sunday. This trough will carve out across the entire eastern CONUS early to mid next week (and likely beyond) bringing the coolest airmass since this past Spring. Scattered showers and thunderstorms will accompany the strong cold frontal passage Saturday into Saturday night before transitioning to lake- effect rain showers over the "snowbelt" of NE Ohio and NW PA Sunday into early next week given lake surface temps in the upper 70s F and 850 mb temps falling to 5 to 7 C and what looks to be well- aligned W to NW flow. It is getting to be that time of year! Highs will warm into the low/mid 80s ahead of the front Saturday before cooling into the mid/upper 70s Sunday and only low 70s Monday and Tuesday. && .AVIATION /00Z Wednesday THROUGH Sunday/... Low pressure is located over Ohio this evening with a cold front extending from just east of TOL-FDY at 00Z. Coverage of thunderstorms are decreasing as storms move east towards I-77 away from the better instability focused across NW Ohio. With that said, additional scattered showers with a few thunderstorms will continue to develop along the frontal boundary through about 03Z and are most likely to impact MFD, CAK and possibly YNG. After that time, rain may continue at eastern terminals but chances of thunderstorms should be lower. Thunderstorms have been producing heavy rain with visibilities of 1-3 miles. Ceilings have generally been VFR in showers but a large MVFR cloud deck extends west to Chicago and Lake Michigan. Have all terminals trending towards at least MVFR ceilings overnight and most will see at least a few hour window of IFR somewhere in the period between 06-13Z. MVFR visibilities will also be possible with IFR ceilings. Ceilings will lift to MVFR on Wednesday morning but most sites will be BKN-OVC through the period. Outflow from showers have resulted in variable wind conditions tonight. Winds are generally out of the south to southwest ahead of the front and northwest behind the front. Terminals will continue to see winds shift around to the northwest although this could take until 14Z at ERI as the low makes slow progress east across the area. Northwest winds of 5-8 knots overnight will limit fog. Outlook...Non-VFR may continue through Thursday with isolated rain showers and low ceilings, primarily across northeastern Ohio and northwestern Pennsylvania. Additional non-VFR possible in scattered showers and thunderstorms on Saturday, mainly east of I-77. && .MARINE... Low pressure will cross the lake this evening into Wednesday before departing to the east Wednesday night. Winds will be variable at around 10 knots or less through tonight before becoming north/northeast and increasing to 10 to 15 knots during the day Wednesday and 15 to 25 knots Wednesday night through much of Thursday. Small Craft Advisories and Beach Hazards Statements have been issued from Reno Beach OH east from 00Z/8 PM Wednesday night through Thursday evening. Winds/waves may be lower in the far western basin given the shorter fetch so have held off on headlines for this area; may need to add Maumee Bay to Reno Beach in a future update if winds/waves trend higher. Waterspouts are possible with the low/cold front passage tonight into early Wednesday with chances continuing through Wednesday night as a trough lingers over the region. Northeast winds will diminish to 10 to 15 knots late Thursday night with east/northeast winds to 5 to 10 knots anticipated Friday. Winds will then shift to the southwest as a cold front approaches from the west on Saturday morning before becoming northwesterly and increasing to 10 to 15 knots behind the front Saturday night. West flow will continue through Sunday. As of now, marine conditions are forecast to remain below Small Craft Advisory limits, but will need to keep an eye on wind/wave trends as the weekend approaches. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...Beach Hazards Statement from Wednesday evening through Thursday evening for OHZ007-009>012-089. PA...Beach Hazards Statement from Wednesday evening through Thursday evening for PAZ001. MARINE...Small Craft Advisory from 8 PM Wednesday to 11 PM EDT Thursday for LEZ143>148. Small Craft Advisory from 8 PM Wednesday to 8 PM EDT Thursday for LEZ149. && $$ SYNOPSIS...Garuckas NEAR TERM...Garuckas/10 SHORT TERM...Garuckas LONG TERM...Garuckas AVIATION...10 MARINE...15