textproduct: Cleveland

WHAT HAS CHANGED

Given the current trends, thunderstorms during the day seem less likely, though are still possible. Showers and thunderstorms still remain on track along and ahead of the cold front this evening.

KEY MESSAGES

1) Showers and thunderstorms are possible this afternoon with a higher chance along and ahead of the cold front this evening. Some storms may be strong to severe with possible isolated damaging winds and up to quarter size hail.

2) Below average temperatures with high pressure building in starting Sunday afternoon through Tuesday. Potential for frost/freeze Tuesday morning.

3) Unsettled weather returns mid week with a low pressure system moving through the Great Lakes region.

DISCUSSION

KEY MESSAGE 1...

Residual low level clouds from early morning precipitation have started to dissipate in western and northern Ohio and should continue to clear out throughout the afternoon. Temperatures as a result have started to climb up into the low to mid 60s with dew points in the low 50s. Instability will increase as well with the temperatures, though how much it increases will be dependent on if temperatures can climb a bit higher in the upper 60s to low 70s. Currently, MLCAPE is forecast to be around 500-1000 J/kg and MUCAPE near 1000 J/kg by later this afternoon with a few areas possibly reaching above that. Winds shear will also increase ahead of the approaching cold front, though will be on the weaker side with bulk shear around 40 knots. Freezing levels will be low as well, which could support some hail, though given the conditions above, hail around quarter size or less seems realistic. There will also be a strong with an isolated damaging wind threat along and ahead of the cold front. The cold front will pass through the region between late tonight into early tomorrow morning which could carry a strong wind threat with it. Though with instability waning into the late evening, the severe threat will become less likely and should anticipate more showers than thunderstorms.

Scattered rain showers will likely linger behind the cold front across the southern and eastern portions of the CWA into Sunday morning. High pressure builds in Sunday afternoon and rain will clear out by then. Rain totals through tomorrow morning will be minimal, with highest amounts in more persistent rainfall being around a half an inch.

KEY MESSAGE 2...

High pressure will begin to build in Sunday afternoon with generally west to northwesterly low level flow across the region through Tuesday afternoon. Current models have 850 temperatures dropping down to 0 to -3C Monday afternoon into Tuesday morning with winds becoming light to calm during the time frame underneath the high pressure. Drier upper level air will be moving in late Monday as well which should clear the region out of any cloud cover by Tuesday. This will create the potential for some frost/freeze across the region Tuesday morning as temperatures will drop down into the mid to upper 30s with some locations dropping into the low 30s. The colder of those temperatures look to be in eastern Ohio and northwestern Pennsylvania away from the lakeshore. Flow will shift to be out of the southwest Tuesday afternoon on the west side of the high pressure and temperatures will climb into the upper 50s to low 60s for highs.

KEY MESSAGE 3...

A low pressure system will enter the region late Tuesday night as a upper level trough ejects out of the Canadian plains and moves southeast into the Great Lakes region. Precipitation will begin to move in late Tuesday night and persist through much of the day Wednesday. Don't anticipate much thunder with the system given the arrival time, though a rumble of thunder would still be possible out west Tuesday night and then again out east with the front midday Wednesday. Moderate to heavy rain is possible at times which could lead to some higher precipitation totals by the end of the day Wednesday. Will need to monitor the development of the system over the next few days to see the potential for any rainfall related impacts.

AVIATION /18Z Saturday THROUGH Thursday/

Mainly VFR across the TAF sites this afternoon with deterioration to MVFR and IFR vsbys in showers and thunderstorms later this afternoon and evening ahead of a cold front. Anticipate showers and thunderstorms to briefly impact all TAF sites with non-VFR vsbys, though the highest confidence for the strongest storms (i.e., gusty winds in excess of 40 knots and potentially large hail the size of quarters), is at CLE/YNG/ERI. Light rain showers may linger behind the initial line of showers and storms, with gradual clearing expected as a cold front moves south through the area overnight.

Winds are generally out of the southwest this afternoon, 10 to 15 knots with gusts of 20 to 25 knots. Winds will gradually increase over the next several hours to 15 to 18 knots with periodic gusts of 25 to 30 knots possible, especially out west. Winds will abruptly shift towards the north behind a cold front overnight, 5 to 10 knots.

Outlook...Non-VFR expected in widespread showers and thunderstorms Tuesday night through Wednesday. Non-VFR may linger across the eastern half of the area in rain showers and low ceilings on Thursday.

MARINE

Generally quiet marine conditions are expected into early next week with no headlines anticipated. Main concern will be the threat for strong thunderstorms later this afternoon and evening with the potential for gusty winds in excess of 34 knots, particularly across the central and eastern basin of Lake Erie. Otherwise, relatively light winds of less than 15 knots are expected through Tuesday. Slightly stronger south to southwest flow of 15 to 20 knots will develop Tuesday night into Wednesday ahead of a cold front, with winds shifting towards the west to northwest behind the front Wednesday night, 15 to 20 knots. Will continue to monitor for Small Craft potential during this period.

CLE WATCHES/WARNINGS/ADVISORIES

OH...None. PA...None. MARINE...None.