textproduct: Cleveland

WHAT HAS CHANGED

Expanded the Flood Watch further northeast into Northwest Pennsylvania. Flash flooding remains possible into this evening.

KEY MESSAGES

1) Showers and thunderstorms with torrential rainfall will continue into this evening. Flash flooding is possible.

2) The next chance for showers and thunderstorms will be Thursday into Friday as a cold front moves across the area. Heavy rain is possible.

DISCUSSION

KEY MESSAGE 1... Showers and thunderstorms will continue across portions of Northeast Ohio and Northwest Pennsylvania into this evening with torrential rainfall rates of 2 to 4 inches per hour. These extreme rates have already resulted in numerous flash flooding impacts across the area, and additional flash flooding remains possible as showers and storms slowly pivot east and exit the area later this evening and overnight. As a result, have expanded the Flood Watch into Ashtabula, Crawford, and inland Erie Counties through 11 PM this evening. May have to extend in time a portion of the Flood Watch out west that goes away at 6 PM if lingering flooding issues persist.

Otherwise, conditions are expected to slowly improve overnight into Tuesday as high pressure builds into the Great Lakes region. Still could see some isolated to scattered showers and thunderstorms near the OH/PA border Tuesday afternoon and evening, though the overall flooding threat should be lower.

KEY MESSAGE 2... After brief high pressure builds across the region late Tuesday into Wednesday, attention then turns towards the next low pressure system and cold front Thursday into Friday. Confidence continues to increase for scattered showers and thunderstorms to develop Thursday night into Friday afternoon, though recent guidance has suggested a more delayed timing for the cold front which would also point to a lower risk of stronger storms. Depending on the progression of the cold front, could see additional showers and thunderstorms develop Friday afternoon and evening across the southern portion of our area. Will also need to monitor the heavy rain potential with this system as another favorable environment develops towards the end of the week, characterized by PWATs returning to near 1.80 inches.

AVIATION /18Z Monday THROUGH Saturday/

A mix bag of conditions are being observed across the area this afternoon as a weak low pressure system continues to generate showers and storms. Within these storms, conditions have deteriorated as low as LIFR visibilities. These storms are very slow moving and will result in multiple hours of deteriorated conditions at any terminal impacted. Given the uncertainty with timing, opted to use TEMPO to handle much of the convection but will update to prevailing as needed to handle the impacts. All storms will gradually deteriorate from west to east through this evening and into the early overnight hours. Behind these storms, MVFR to IFR ceilings will build in and patchy fog may develop, especially for eastern terminals. These conditions will be slow to improve on Tuesday morning, likely keeping at least MVFR ceilings around into the late morning. The exception may be KTOL and KFDY which may be able to rebound much quicker.

Northeast winds of 10-12 knots are expected through this afternoon before becoming light and variable overnight. As the center of the low drifts east tomorrow, winds will gradually gain a more northerly component and increase to 8-12 knots again Tuesday afternoon.

Outlook...Non-VFR with occasional showers and thunderstorms possible through Tuesday afternoon. Scattered thunderstorms are also possible Thursday afternoon through Friday afternoon.

MARINE

A very slow moving meso-low currently centered over northern Ohio has maintained a northeasterly flow across Lake Erie this afternoon. Winds of 15-20 knots have resulted in waves of 1-4 feet across the western and central basins. Given this continued flow and increased risk of rip currents, a Small Craft Advisory and Beach Hazards Statement remain in effect through 10 PM EDT.

As the center of this aforementioned low gradually moves east Tuesday, winds will gradually gain a more northerly component and be sustained at 5-10 knots. This will keep nearshore wave heights across the central basin 1-3 feet on Tuesday. Winds on Tuesday night will become light and variable as a high pressure system builds east and persists through Thursday night. On Friday, another cold front is expected to sag south across the lake, allowing for southwest winds to gradually become northwesterly Friday afternoon. This may allow waves to build to around 2 feet, but no marine headlines are anticipated at this time. High pressure returns this weekend.

CLE WATCHES/WARNINGS/ADVISORIES

OH...Flood Watch until 6 PM EDT this evening for OHZ003-006>009-019. Beach Hazards Statement until 10 PM EDT this evening for OHZ003-007-009>011. Flood Watch until 11 PM EDT this evening for OHZ010>014- 020>023-029>033. PA...Flood Watch until 11 PM EDT this evening for PAZ002-003. MARINE...Small Craft Advisory until 10 PM EDT this evening for LEZ142>146.