textproduct: Cleveland

WHAT HAS CHANGED

Heavy rain is possible from Marion to Mount Vernon early this morning. The PoP forecast for Saturday night into Sunday has been increasing as confidence in location and timing improves. A small area (approximately Findlay to Marion) was upgraded to a Slight Risk for severe weather Saturday night. There is a slight risk (level 2 of 4) for excessive rainfall on Saturday for most Ohio Counties (excluding far northeast Ohio).

KEY MESSAGES

1) Scattered showers and thunderstorms continue through today near and south of the US-30 corridor. Heavy rain is possible from approximately Marion to Mount Vernon this morning.

2) Showers and thunderstorms will return Saturday night through Sunday. Heavy rain is likely Saturday night, with a few stronger storms possible Sunday afternoon and evening.

DISCUSSION

KEY MESSAGE 1... A surface stationary boundary lingers over the lower Ohio Valley, though forcing in the 850-700 mb layer extends well north of this boundary. In the immediate near term, light to moderate rain showers have generally remained south of a Wood to Wayne County line. Showers should gradually expand northward to as far as a Toledo-Lorain-Akron line but the risk for heavy rain is likely to rain towards our southwest counties (Marion to Knox) where the latest HRRR cycles project an inch of rain. The risk for >2" of rain and subsequent flooding is low but not completely out of the question, so we'll have to monitor for that this morning. Rain showers dissipate through the afternoon and we should be completely rain free by around 21Z.

KEY MESSAGE 2... The next period for unsettled weather will be Saturday night through Sunday as a low pressure system moves east across the Great Lakes.

A stationary front lingering over the Ohio Valley will lift northward across the area Saturday night in response to low pressure tracking across the Great Lakes region. A period of heavy rain is becoming more likely Saturday night as a highly- anomalous moist air mass, characterized by PWATS exceeding 2.0 inches, which is approaching the climatological maximum, enters the area. There is a slight risk (level 2 of 4) for excessive rainfall and a marginal risk (level 1 of 5) for severe weather Saturday night with a slight risk (level 2 of 5) from Findlay to Marion.

The latest model guidance continues to be trending the strong to severe storm threat further south of the area as any redevelopment in the afternoon will likely focus along the residual boundary from the overnight convection.

AVIATION /06Z Friday THROUGH Tuesday/

Light rain showers are sweeping southeast across southern terminals. Areawide VFR conditions will deteriorate to MVFR, with patchy IFR, in patchy fog and low ceilings. Highest confidence in MVFR or lower will be across inland terminals in western and central portions of the airspace. Expect for any reductions to improve after daybreak this morning.

Light and variable winds overnight tonight will become east- northeast while increasing to 5-10 knots this afternoon.

Outlook...Non-VFR possible in showers and thunderstorms Saturday afternoon into Sunday.

MARINE

Weak high pressure builds across the Great Lakes today and tomorrow. Conditions should be relatively quiet through Saturday.

Low pressure moving eastward across the Great Lakes region brings a warm front across Lake Erie Saturday night into Sunday morning, followed by a cold front Sunday evening into Sunday night. There is a low possibility for offshore flow reaching or exceeding 20 knots Saturday, though probabilities of winds > 20 knots and waves > 4 ft increase Sunday into Sunday night as winds become west to northwest. Will need to monitor the need for a Small Craft Advisory and Beach Hazard Statement for this period.

CLE WATCHES/WARNINGS/ADVISORIES

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