textproduct: Cleveland

WHAT HAS CHANGED

There is a Marginal Risk (Level 1 of 5) for severe weather for Northeast Ohio and Northwest PA today. Some showers and storms could be strong to severe with gusty winds and large hail.

KEY MESSAGES

1) Several rounds of showers and storms remain possible through Thursday night. Some showers and storms could be strong to severe in Northeast Ohio and Northwest Pennsylvania this afternoon with gusty winds and large hail. Broader coverage of showers and storms are possible in Central Ohio on Thursday afternoon and evening; locally heavy rain and nuisance flooding is possible.

2) Showers and storms could return as early as Saturday afternoon. Rain coverage will increase into Sunday.

DISCUSSION

KEY MESSAGE 1... The northwest flow pattern aloft and stalled front to the southwest will continue to dictate the weather across the area through Thursday night. For today, a mid-level shortwave will ripple through the northwest flow this afternoon. This will support a surface trough the will move through the eastern Great Lakes and flare up showers and storms in Northeast Ohio and Northwest PA this afternoon and evening. With better lift in this area and some instability, some storms could be stronger with gusty winds and large hail, but any severe event would be isolated. Further southwest, the shortwave will reinvigorate showers and storms along the front in Indiana and Southwest Ohio. Some of these could spread into Northwest and Central Ohio this afternoon. Any afternoon and evening activity should largely wipe out instability and any large development tonight, but some stray showers may develop over and near the lake with some isentropic lift over the area.

For Thursday into Thursday night, the front to the southwest will try to lift north and get into Central Ohio, if not into the southwest portions of the forecast area. One more shortwave will ripple through the northwest flow aloft and allow for more rain and storms to develop. Believe that any storms with any bite to them will be southwest of the forecast area with the better instability. However, any storms will have heavy rain and the potential for localized flooding does exist. High pressure will build from the northwest for Friday, pushing the front and rain chances out of the area.

KEY MESSAGE 2... The upper ridge over the Ohio and Tennessee Valleys will recede south a bit on Saturday into Sunday and allow for northwest flow on the northeast side of the ridge. This will allow for a series of shortwaves to move through the region starting as early as Saturday afternoon with most impacts on Saturday night into Sunday. These shortwaves will support shower and storm chances across the area. There is a non-zero chance for strong to severe storms on Sunday with a more organized surface low moving through the eastern Great Lakes region. Temperatures ahead of the low and Sunday convection could get into the mid 80s.

AVIATION /06Z Wednesday THROUGH Sunday/

Fog is the main aviation concern early this morning. Wet ground and an inversion setting up will support widespread fog, which could be dense at times. The longest periods of LIFR visibilities will likely occur at KTOL, KFDY, KMFD, KCAK, and KYNG, with visibilities more favoring IFR closer to the lake at KCLE and KERI, but even those terminals could see brief LIFR.

The fog will lift fairly rapidly by mid morning, but cigs are trending lower through much of the afternoon, so brought in longer MVFR cigs. VFR should return faster this afternoon at KCAK, KYNG, and KERI compared to farther west because showers and a few thunderstorms will approach western terminals late this afternoon and evening, so introduced some precip as well, with the greatest chances for rain occurring at KTOL, KFDY, KMFD, and KCAK since the activity will move SE across western and central terminals.

Light and variable winds early this morning will become SW at 5-10 knots this afternoon and evening.

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

MARINE

Quiet conditions will continue on Lake Erie through Thursday as the active frontal boundary slowly shifts south and high pressure attempts to briefly build into the Great Lakes. SW winds of 5-10 knots today will become light and variable tonight and Thursday before turning NE and increasing to 5-15 knots by Friday and Friday night as the high becomes better established. Winds will back to E to SE Saturday and eventually turn S to SW by Sunday as a warm front lifts north, with speeds increasing to 10-20 knots Sunday.'

Scattered thunderstorms could bring locally higher winds and waves this evening and again this weekend.

CLE WATCHES/WARNINGS/ADVISORIES

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