textproduct: Cleveland

WHAT HAS CHANGED

A Flood Watch has been issued for portions of North-Central and Northeast Ohio into this evening as torrential rainfall and isolated flash flooding remain possible.

KEY MESSAGES

1) Showers and thunderstorms will continue into this evening. Torrential rain and isolated flash flooding is possible.

2) Temperatures will trend warmer by early to mid-next week with limited precipitation chances.

DISCUSSION

KEY MESSAGE 1... Showers and thunderstorms continue across the area this afternoon, with recent satellite and radar trends suggesting additional development possible to the north and northwest of existing cells over the next couple of hours as surface convergence increases to the south ahead of a weak cold front and associated outflow boundaries. The main concern with any showers and storms into this evening continues to be a heavy rain and isolated flash flooding threat. Although the Flood Watch area across portions of North-Central and Northeast Ohio denotes the highest confidence area for flooding impacts, any showers and storms may contain torrential rainfall rates of 2 to 3 inches per hour into this evening given the favorable environment in place, characterized by weak flow and PWATs exceeding 1.80 inches.

Coverage of showers and storms will gradually decrease after sunset this evening as the cold front sags south, settling near or just south of the US-30 corridor overnight. Isolated to scattered showers and isolated thunderstorms will remain possible overnight into Saturday, particularly near the US-30 corridor, as a wave of low pressure tracks east into the Ohio Valley.

KEY MESSAGE 2... A warmer and drier pattern appears favored by the end of the weekend through mid-next week as a large upper-level ridge develops across much of the CONUS. The eastern periphery of the ridge may begin to break down towards the end of the week as an upper-level trough swings east across New England, though limited precipitation is expected for much of the week. Temperatures will return to above average by as early as Sunday with highs in the mid to upper 80s, further increasing into the low to perhaps mid-90s by Tuesday and Wednesday. Will need to monitor temperature and humidity trends during this timeframe as heat indices rise into the mid to upper 90s, yielding at least some pockets of major heat risk on Wednesday.

AVIATION /18Z Friday THROUGH Wednesday/

Numerous showers and thunderstorms have developed across northern Ohio this afternoon as a cold front slowly moves south. The lake breeze should keep activity away from Cleveland and Erie but thunderstorms are ongoing from TOL to near MFD, and extending east to CAK and YNG. Included tempos for all inland terminals this afternoon but will likely be done at TOL/FDY by 20Z. It is unclear at this time if YNG will get additional storms later on. Humidity is high and thunderstorms are producing heavy rain and IFR visibilities. Wind gusts are most typically around 30-40 knots with an isolated gust to 50 knots possible. Thunderstorms are expected to be done at terminals by 23Z.

Locations that receive heavy rain this afternoon have the potential for fog to develop overnight. Mid and high cloud may hang around through 06Z but could see visibilities start to decline late tonight at MFD/CAK/YNG. Included MVFR visibilities with a tempo for IFR visibilities. Conditions are expected to improve quickly on Saturday morning.

Winds have generally been southwesterly ahead of the cold front, veering to the north/northeast behind the front. Winds are out of the east at TOL and north to northeast at CLE and ERI. Winds will be light and variable overnight.

Outlook...VFR expected.

MARINE

A front is pushing south across Ohio this afternoon with northeasterly winds expected on Lake Erie on Saturday. The wind forecast has trended slightly higher along the south shore of Lake Erie and a moderate swim risk expected. Conditions will be choppy but expected to be just below Advisory criteria with 2 to 4 foot waves. Northeast winds decrease Saturday night then increase again on Sunday afternoon with winds around 15 knots and waves around 2-3 feet.

Marine conditions improve Monday as high pressure builds overhead. Winds become southwest Tuesday and Wednesday as high pressure departs to the southeast. Waves generally expected to be less than 1 foot.

CLE WATCHES/WARNINGS/ADVISORIES

OH...Flood Watch until 10 PM EDT this evening for OHZ021>023- 029>033-037-038-047. PA...None. MARINE...None.