textproduct: Cleveland

WHAT HAS CHANGED

No significant changes to the forecast as it remains on track.

KEY MESSAGES

1) Periods of showers and thunderstorms continue through today as a front wavers across the Ohio Valley.

2) Unsettled weather pattern continues into the weekend. Heavy rainfall and localized flooding are possible Saturday into Sunday.

DISCUSSION

KEY MESSAGE 1... Surface boundary remains draped across the Ohio Valley region today with periods of showers and storms continuing as numerous shortwaves aloft move overhead through this evening. Showers and storms will be capable of producing heavy rainfall with localized flooding possible. Both REFS and HREF composite reflectivity ensemble paintballs indicate two primary windows where shower and storm coverage increase. The first window will be early this morning into daybreak as a wave aloft moves overhead. Area of coverage will include portions of Northwest and Central Ohio. Another wave enters the region late this morning/early afternoon where storms may dive southeast from Northern Indiana towards Central Ohio. Low confidence in any storm reaching severe limits today as best instability remains south and west of the forecast area.

By this evening, the front will exit to the south as Canadian high pressure enters from the north. There may be some lingering showers this evening before the high takes full control of the weather pattern by Friday.

KEY MESSAGE 2... Dry conditions are expected through Friday evening before high pressure exits to the east Friday night into Saturday. Precipitation chances return from the northwest overnight Friday into Saturday as low pressure lifts a warm front across the local area. The low will then drag a cold front from northwest to southeast Saturday into Sunday. The primary concern with this system continues to be heavy rainfall and localized flash flooding. WPC has maintained a Slight Risk (Level 2 of 4) Excessive Rainfall Outlook for this timeframe across the western half of the forecast area. Highest axis of QPF remains north of the forecast area in a swath from Chicago/Milwaukee east towards Detroit.

AVIATION /06Z Thursday THROUGH Monday/

A moist airmass remains in place across the local area. Conditions at 06Z vary from LIFR with stratus to VFR with a mid-level cloud deck. Overall stratus deck across the northern terminals is expected to persist while inland sites like MFD/CAK/YNG could see more breaks in the mid-level clouds, allowing for these areas to quickly fill in with a very low stratus. Ceilings will trend lower overnight with the potential for some patchy dense fog, especially in the 08-12Z time frame. MVFR clouds will persist for most of the day on Thursday.

The local area is experiencing a break in precipitation. It does seem that the most organized potential for showers will be across Northwest Ohio between 12-18Z with highest probabilities at FDY. Confidence in thunderstorms was not high enough to include a mention at this time but updates may be needed to add thunder to some terminals. Scattered showers are also possible at remaining terminals as the front settles south between 09-15Z but these are expected to be both lighter and more intermittent so mainly only include showers in the vicinity for now.

Winds will be generally light and variable overnight as a frontal boundary bisects the area. Southern terminals will start off with southwesterly winds in the morning, then transition to west or northwesterly as the front pushes south through early afternoon. Winds will remain 10 knots or less.

Outlook...Non-VFR possible with showers and thunderstorms Saturday through Sunday.

MARINE

North to northeast winds of 5-10 knots are expected on Lake Erie today, then increasing to 15-20 knots for a brief window late tonight into Friday morning. Waves will be choppy given the onshore flow and will increase to 2 to 5 feet on the central basin of Lake Erie on Friday morning. Winds will decrease by Friday afternoon but then veer to easterly at 10-15 knots Friday night through Saturday.

Low pressure will pass near or just south of Lake Erie on Saturday night. The track of the low will impact wind direction and wave heights as a brief window of southerly flow would yield better marine conditions than a more prolonged stretch of north to northeast winds. Once the northeasterly flow becomes established on the back side of the system, rough marine conditions can be expected on the central and western basin of Lake Erie from Sunday through Tuesday with the potential for winds to reach 30 knots at times. A prolonged Small Craft Advisory will likely be needed late this weekend through early next week.

CLE WATCHES/WARNINGS/ADVISORIES

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