textproduct: Cleveland

WHAT HAS CHANGED

No significant changes to the forecast. There is still potential for strong to severe thunderstorms Sunday and especially Monday, but confidence in timing and placement of storms remains low.

KEY MESSAGES

1) Multiple rounds of showers and thunderstorms are likely across the area Sunday through Wednesday. Storms may occasionally be strong to severe Sunday through Monday night with the highest confidence on Monday.

DISCUSSION

KEY MESSAGE 1... Dry weather will continue through at least early Sunday before an unsettled weather pattern unfolds Sunday through Monday night.

A ridge will be in place to the west of the local area through Monday with a trough setting up across the northeastern CONUS. A series of disturbances will crest the ridge Sunday through Monday night, resulting in multiple chances of showers and thunderstorms through the start of the week. There's still quite a bit of uncertainty in the timing/placement of thunderstorms and the resulting severe weather threat across the local area. Thunderstorm chances and the trajectories of any MCS activity will rely on mesoscale features that have yet to be resolved.

Some CAMs suggest that scattered diurnal showers and thunderstorms could develop southeast of Lake Erie Sunday afternoon. There may be an isolated severe weather threat during that time given the increasing moisture and instability across the area, but the threat is pretty isolated at this point. Meanwhile, an MCS will follow an instability gradient and push south/southeast from the Upper Midwest during peak heating before either clipping or missing the local area just to the west Sunday evening or overnight. Will need to continue to monitor CAMs and adjust the forecast as needed; as of now confidence in severe weather potential Sunday is low and the threat is conditional. There is a Marginal Risk (Level 1 of 5) of severe weather across most local Ohio zones.

Confidence in thunderstorms is higher for Monday since the ridge will be shifting east into a more favorable position for convection making it into the area. There may be periodic showers/thunderstorms throughout the day Monday, although thunderstorm chances will rely on how Sunday night/early Monday morning pans out. Another MCS will likely push southeast or develop along remnant boundaries across the region at some point late in the day Monday into Monday night. Deep layer shear will be higher on Monday thanks to better upper level support as a cold front approaches so there is a Slight Risk (Level 2 of 5) of severe weather across the entire area Monday/Monday night. Damaging wind gusts will most likely be the main threat. Will continue to keep an eye on model trends and update the forecast/messaging as confidence in timing and coverage increases.

Shower and thunderstorm chances will continue into Tuesday with lake- enhanced rain showers/thunderstorms possibly continuing across NE OH/NW PA into Wednesday due to persistent troughing overhead. Dry weather will return by early Thursday as high pressure briefly builds in from the west.

AVIATION /06Z Sunday THROUGH Thursday/

Some 5SM BR at the terminals away form the lake towards morning for a few hours, using TEMPO instead of prevailing. VFR, another cumulus field this afternoon FL035-045. Winds WSW/W 10kts at the surface. Convective chances increasing, especially after 00Z for the western terminals as will have to watch incoming complexes from the north, but no mention at terminals for now as chances low through 06Z Monday

Outlook...Non-VFR possible with periodic showers and thunderstorms Sunday night through Tuesday.

MARINE

Quiet conditions will continue on Lake Erie through Monday with generally light winds. The exception will be any thunderstorms that can slide across the lake Sunday evening and especially Sunday night and Monday as a very active warm frontal boundary pushes slightly farther east into the area ahead of a low pressure system and strong cold front expected to cross Monday night. Any thunderstorms could contain severe winds.

Stronger synoptic winds will develop behind the cold front Tuesday. W winds will increase to 15-20 knots Monday night, turning NNW at 15-25 knots Tuesday and Tuesday night before NNW winds gradually decrease Wednesday and Wednesday night. However, winds may remain sub 20 knots through Wednesday evening. Small Craft Advisories and Beach Hazard Statements for rip currents will be needed Tuesday and possibly through Wednesday evening. Winds will become light northerly by Thursday.

CLE WATCHES/WARNINGS/ADVISORIES

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