textproduct: Cleveland

WHAT HAS CHANGED

Forecast model guidance has trended a little slower and wetter for the weather system that will move across the area later today through Saturday night. Temperatures are expected to warm up and feel more like summer later next week.

KEY MESSAGES

1) A slow low pressure system will track from the Lower Ohio Valley into the eastern Great Lakes later today through Saturday night bringing widespread moderate to locally heavy rainfall for the holiday weekend. There may a potential for localized minor flooding impacts to low lying areas and locations with poor drainage.

2) By early to middle of next week, a warmer summer-like weather pattern will develop over the Great Lakes and Ohio Valley region.

DISCUSSION

KEY MESSAGE 1... Our weather will start out with fair conditions and dry this Friday morning, but a weather system will quickly approach from the southern U.S. bringing a soggy start to our Memorial Day Weekend. The low pressure system that will impact our weekend weather is currently near the Mid-Mississippi Valley this morning. Ahead of that system, clouds will increase and thicken throughout today. Our afternoon temperatures will climb into the middle and upper 60s with some locations possibly reaching 70 degrees.

The wet storm system will track northeastward into the Ohio Valley later today and tonight. The surface low will track towards northwest Ohio and western Lake Erie by Saturday afternoon. Scattered showers and isolated thunder will develop south of our area later today and advance northward into northern Ohio late this afternoon into the evening. Widespread areas of showers and isolated thunder will spread across the entire area overnight into Saturday morning.

This system will have alot of tropical moisture to work with. It is bringing some very rich moisture content with PW values approaching 1.6" tonight into Saturday, which is near the max value for climatology at the end of May standards. Storm total rainfall amounts will average from 1.0-1.5 inches. Some locations closer to the Highway 30 corridor and southward into central Ohio and northeastern Ohio may end of with up to 2 inches of rainfall this weekend. There are some concerns for a localized flooding threat for the usual prone spots that are low lying and have poor drainage. The localized flood threat will be something we will monitor and nowcast as this rain event unfolds.

There are some indications from the high-res models that as the surface low lifts northeastward across Lake Erie late Saturday afternoon/evening, some scattered convection may try to develop over eastern Ohio. But this broken line of convection will be just general thunder and we are not expecting anything organized or strong at this time. Saturday's high temperatures will have a wider range from west to east. Western areas may reach up into the lower 70s Saturday afternoon, but it will be cooler eastward in the upper 50s to lower 60s for far NEOH and NWPA where the steadier rain holds on longer through the day.

Another weak surface trough of low pressure will swing from west to east across the area Sunday into early Monday with additional chances for scattered showers and isolated thunder. Temperatures will start to climb upward Sunday and Monday with highs in the middle to upper 70s. Some parts of the area will start to see drier weather try to move in from north to south during the day Monday or later Monday afternoon.

KEY MESSAGE 2... The overall weather pattern shifts in a big way by early to middle of next week which favors summer-like temperatures. The model guidance for next week has been showing fairly good agreement on a psuedo Omega Block weather pattern developing over the north central CONUS, eventually shifting slowly eastward over the Great Lakes region by next weekend. This pattern will favor warmer weather with highs into the 80s and overnight lows in the 60s. It will also favor lower rain chances but not completely zero. It will finally start feeling like Summer and that very warm weather may last for multiple days.

AVIATION /06Z Friday THROUGH Tuesday/

TAFs are currently VFR with some high and mid level clouds across the region. Low pressure will begin to move north into the region tomorrow morning and ceilings of 3.5-6 kft will develop around 12- 15Z. There will be pockets of MVFR ceilings developing mid day, primarily in the southern TAF sites of KFDY, KMFD, KCAK, and KYNG. Through the day MVFR ceilings will spread northward, then drop down to IFR with the incoming rain showers. Timing of the rain looks to have trended slower and adjustments have been made in the TAFs to account for this. Current timing is around 22Z for the southern sites and 01-02Z for northern ones. Rain showers are anticipated through the end of the TAF period at this point.

Winds will be primarily out of the east-northeast at 8-15 knots throughout the TAF period as the surface low will have yet to move this far north. There will be a period of gusty winds of 20-25 knots tomorrow during the day before easing a bit in the evening.

Outlook...Non-VFR expected at times Friday evening through late Saturday evening. Non-VFR possible late Sunday into Monday.

MARINE

Unsettled marine conditions will continue through late Saturday night with a Small Craft Advisory and Beach Hazard Statements currently in effect. Winds will be primarily out of the east to northeast across the lake through late Saturday night ahead of the a surface low pressure system. In the central and western basins, winds will be between 20-25 knots and in the eastern basin be around 15-20 knots. By late Friday night, winds will shift to be more southeasterly and be 15-25 knots across the lake. During this time, waves will build to be around 5-8 feet across the central and eastern basins.

By Saturday evening, low pressure will track across the region and shift to be out of the south, then out of the west to southwest by Sunday morning. Winds will begin to diminish from west to east throughout the day Saturday with the eastern basin hanging on to elevated with of around 20 knots into late Saturday night. A headline extension may be needed if winds continue trend higher through Saturday evening. By Sunday, winds and waves will have diminished and are expected to be light and variable through mid week.

CLE WATCHES/WARNINGS/ADVISORIES

OH...Beach Hazards Statement through Saturday morning for OHZ003- 007-009-010. Beach Hazards Statement through this evening for OHZ011-012- 089. PA...Beach Hazards Statement through this evening for PAZ001. MARINE...Small Craft Advisory until 10 AM EDT Saturday for LEZ142>145. Small Craft Advisory until 10 PM EDT this evening for LEZ146>149.