textproduct: Cleveland

WHAT HAS CHANGED

There is a marginal risk (level 1 of 5) for a couple strong to severe thunderstorms this afternoon and evening. The main severe weather threat will be damaging wind gusts.

KEY MESSAGES

1) Warm and unsettled with periodic chances for scattered showers and thunderstorms through Saturday afternoon.

2) Strong to severe thunderstorms are possible Monday. Heavy rainfall is also possible early next week.

DISCUSSION

KEY MESSAGE 1... A quasi-stationary front is currently located across the region. There is a warm and very humid airmass also across the region. Widely scattered showers and storms are redeveloping this afternoon with some help from a weak lake breeze and old outflow boundaries too. A broad upper level trough has setup over the Great Lakes region. Around the base of this upper level trough will bring weak disturbances to aid in the development of scattered showers and storms. A round of scattered convection is expected to develop this afternoon for areas of NEOH and NWPA. This round will move eastward through the evening. Another round of scattered convection will develop over NWOH later this evening and track eastward across northern Ohio into NWPA overnight. A couple strong to severe storms may be possible with damaging wind gusts as the main threat. There is a marginal risk (level 1 of 5) highlighted from SPC for the rest of today.

We will start off the day Saturday fairly quiet. But the quasi- stationary front will push through as as weak cold front during the afternoon with additional scattered showers and thunderstorms possible. Weak high pressure will build into the area Saturday night and Sunday with a drier forecast. High temperatures will be in the 80s and overnight lows in the 60s.

KEY MESSAGE 2... The weather pattern becomes more unsettled for the early part of next week. A broad upper level trough will continue to be over the Great Lakes region for early next week. Another cold front will drop down through the Great Lakes on Monday and slow down as it moves into our area. Multiple rounds of convection will be possible along this slow moving or quasi-stationary boundary Monday through Wednesday. SPC has highlighted the area in a Day 4 severe weather outlook on Monday. The main severe weather threat will be damaging wind gusts and large hail. Heavy rainfall will also be a concern for Monday into Tuesday. WPC has the area highlighted in a slight risk for excessive rainfall both Monday and Tuesday. Timing of these multiple rounds of convection is a little uncertain at this time. Widespread several inches of rainfall is very possible Monday through Wednesday. The quasi-stationary front may finally push south of the area by Thursday into Friday with lower rain chances and slightly cool, less humid air.

AVIATION /18Z Friday THROUGH Wednesday/

Showers are beginning to initiate along a line from Huron County northeast to Lake County. Expect for this area of showers to increase in coverage while sinking southeastward across terminals through this evening. Isolated thunderstorms are expected to develop as this line forms. Opted to maintain PROB30 groups for TS impacts at all TAF sites along and east of I-71 as showers and storms will remain isolated to scattered in coverage.

The initial push of showers/storms will exit to the southeast this evening (~22Z/Fri-00Z/Sat) giving way to a brief break tonight. A remnant shower/thunderstorm will enter the region overnight tonight, mainly across inland terminals. Confidence in coverage remains low so opted to continue PROB30 lines at appropriate TAF sites.

Winds will remain southerly this afternoon and evening before shifting more southwesterly tonight into Saturday morning.

Outlook...Periods of non-VFR anticipated in scattered showers and thunderstorms Saturday, Monday, and Tuesday.

MARINE

Southerly to southwesterly flow 5-15 knots continues through tonight before low pressure gliding east through the Great Lakes drags a cold front across Lake Erie on Saturday. Winds will turn onshore behind the front Saturday night, remaining between 10-15 knots. Waves are expected to remain 2 feet or less through the weekend. An area of high pressure will move overhead on Sunday leading light winds through Sunday evening. Winds eventually favor southwesterly and return to 10-15 knots Sunday night through midweek. Marine headlines are not anticipated given largely offshore flow through the weekend and beginning of next week.

CLE WATCHES/WARNINGS/ADVISORIES

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