


Area Forecast Discussion
Issued by NWS Cleveland, OH
Issued by NWS Cleveland, OH
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140 FXUS61 KCLE 032002 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 402 PM EDT Thu Apr 3 2025 .SYNOPSIS... Low pressure moves off into Eastern Canada as a frontal boundary wavers north and south over the Ohio River Valley this evening. Low pressure systems will track northeast into the region through the weekend bringing moderate to heavy rain at times. Another low pressure will approach from the northwest on Monday bringing much colder air and the potential for light snow to start the week and high pressure will build in behind. && .NEAR TERM /THROUGH FRIDAY NIGHT/... An upper level trough currently located over the western half of CONUS will be slowly moving eastward as a strong jet and accompanying LLJ push northward from the south into the Great Lakes region. The LLJ will start to really get going late Friday night with models showing a 50kt LLJ moving into the region bringing ample moisture advection. The current break in the rain will end late this evening as precipitation will return as the boundary over the Ohio River Valley wavers to the north overnight tonight. Most of the precipitation will stay in the southern portion of the CWA, with areas south of U.S. Route 30 seeing between 0.25-0.50 inches of rain through Friday morning. Areas north will see less than 0.25 inches of rain. There will be drier weather during the day Friday, as the boundary drifts back south. The next round of precipitation will return Friday evening into the overnight hours as a low pressure system and warm front move north across the region. The bulk of the precipitation is expected to fall late Friday night with an overall QPF expected to be between 0.50-1.00 inches during the overnight hours. Areas west of I-71 will be closer to 1.00 inch total during that time period with locally higher amounts possible as well. With the rainfall received Wednesday night, flooding of rivers, streams, and street flooding is a concern. Will need to continue to monitor into the weekend. Temperatures will stay mild through the period with highs in the low 50s on Friday and overnight lows being in the mid to upper 40s. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... Active weather continues into the start of the weekend, with a front wavering across the northern Ohio Valley through early Sunday before getting shunned farther to the southeast Sunday into Sunday night. A weak shortwave and associated wave of surface low pressure will be riding along the front across the area to start Saturday, with another round of widespread rain and perhaps a bit of thunder ongoing. We will see a bit of a break in the rain during the day Saturday behind the low as the front pushes a bit to the southeast. Another shortwave and associated wave of weak surface low pressure will ride along the front Saturday night into Sunday, bringing another round of rain...particularly across our southern counties. A brief spell of high pressure and drier weather builds in late Sunday and Sunday night as the front finally pushes far enough to our southeast to allow dry air from the north to win out. A modest severe threat may develop on the warm side of the front by early Saturday afternoon amid a weakly unstable, strongly sheared environment. There is some model disagreement on how quickly the front pushes southeast and out of our area Saturday morning/early afternoon, though a slower front would increase concern for severe weather locally. Overall a rather conditional threat, and feel the SPC Day 3 Marginal Risk (level 1 of 5) sufficiently covers it for now. Damaging winds would be the main concern, with a non-zero tornado threat owing to the strong low-level and deep-layer shear. The greater concern for the weekend will be continued hydro/flooding concerns. The current forecast has an additional 1.00-2.00" of rain from Saturday morning through Sunday from approximately a Findlay to Sandusky line points southeast, with the greatest amounts towards Mt Vernon. There is some uncertainty regarding the northern extent of the heavier rain potential, particularly Saturday afternoon and beyond. The overall axis has shifted south slightly with this forecast package, but is still enough rain to maintain river flooding concerns through the weekend as it is. Will also need to watch for localized flash or urban flooding with any training convection on Saturday (if convection materializes before the front pushes southeast), along with Saturday night if we get a quick hit of 1.00"+ of rain as some guidance suggests. The Flood Watch remains as posted along and west of I-77 until Sunday morning, and those with flood-related concerns should continue monitoring rainfall forecasts, river levels, and river level forecasts. Highs on Saturday will range from the upper 50s in Toledo to the 60s for much of the area, possibly touching 70 towards Canton and Youngstown if the front is slow enough to push back southeast. Lows Saturday night much chillier, mainly mid 30s to near 40. Highs on Sunday will be stuck in the 40s, with a frosty night Sunday night with lows in the upper 20s/lower 30s. && .LONG TERM /MONDAY THROUGH THURSDAY/... A potent trough with a tap of lingering arctic air over Canada will swing through the Great Lakes Monday into Tuesday. This deeper/colder trough will lift out fairly quickly towards mid-week, though general longwave troughing will persist over the Northeast through the remainder of the long term, maintaining cooler than normal conditions. An arctic cold front (or at least an April version of one) will blast across the area Monday afternoon/evening. A band of rain/snow showers may accompany the front, with a quick blast of wind gusts over 30 MPH along and just behind the front. There is good agreement on 850mb temperatures plummeting to -14C to -16C Monday night into early Tuesday with 700mb temperature bottoming out at -20 to -23C. Over lake water temperatures of 2-4C, this yields fairly strong instability over the lake for a brief window late Monday night into Tuesday morning, with at least some lingering synoptic moisture to at 850mb, possibly higher if the GFS/European are correct with a more amplified trough. Given this, have at least a chance for snow showers lingering in the snowbelt through Monday night into Tuesday morning. Accumulating lake effect snow is not unheard of in April, and if guidance doesn`t back off the depth of the trough the higher terrain of the snowbelt could get an unwelcome (we are assuming here) blanket of snow into early Tuesday. Accumulations shouldn`t be heavy, but could easily be measurable and perhaps on the order of a couple inches in the higher terrain. Locations outside of the snowbelt should dry out quickly Monday night after the cold front exits, though a few flurries may occasionally linger in the air through early Tuesday anywhere in the cold/cyclonic flow...and any lake effect should wind down/end quickly on Tuesday due to a combination of the deep trough quickly departing and negative diurnal influence on lake effect during the day this time of year. High pressure should bring dry but chilly weather later Tuesday through at least Wednesday. The next shortwave likely approaches from the west Wednesday night or Thursday, though timing and strength varies significantly on current guidance. This leads to a gradual ramp up to 30-40% type POPs for rain by Thursday. Temperatures will be a bit cooler than average Monday...much below normal Tuesday...and gradually trending towards (but still not getting back to) normal by Thursday. && .AVIATION /18Z Thursday THROUGH Tuesday/... Terminals are VFR across the region and should remain so through the evening. There is a 040-060 kft ceiling across the eastern sites that will persist until showers move into the region from the south-southwest tonight after 00Z. Ceilings and vis are expected to drop to MVFR with the showers and persist through 12Z tomorrow morning when the showers begin to move to the south. Winds will be gusting this evening up to 30 knots before subsiding to below 12 knots after 00Z with no gusts expected through the rest of the TAF period. Outlook...Non-VFR ceilings will return across the region into Friday with some non-VFR visibility possible in showers and storms, mainly towards the southern part of the forecast area. Non-VFR more likely areawide in showers and thunderstorms Friday night into Saturday with non-VFR ceilings continuing into Sunday. && .MARINE... West-southwest winds are brisk and gusty this afternoon. Small Craft headlines continue from Cleveland points east through 8 PM this evening. Winds are reaching the 20kt sustained criteria at times farther west this afternoon and contemplated expanding the advisory, though should be on their way down into this evening so held off due to the brief/marginal nature of the conditions. Expect relatively quiet marine conditions tonight into Friday. East-northeast winds pick up to nearly 20 knots Friday night into early Saturday, and could build waves enough to warrant a Small Craft Advisory for western zones. Winds turn southwest and then northwest through Saturday as low pressure passes by just to the south of the lake and diminish to 10-15kt. Winds will remain onshore at up to 15kt through Sunday and will maintain choppy conditions, though should be under headline-criteria. Headlines will be needed as a strong cold front crosses Monday afternoon/evening, ushering in strong northwest flow. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...Flood Watch through Sunday morning for OHZ003-006>011-017>021- 027>032-036>038-047. PA...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for LEZ146>149. && $$ SYNOPSIS...23 NEAR TERM...23 SHORT TERM...Sullivan LONG TERM...Sullivan AVIATION...23 MARINE...Sullivan