textproduct: Cleveland

WHAT HAS CHANGED

No significant changes to the forecast with this update.

KEY MESSAGES

1) A few rounds of showers and thunderstorms are expected late tonight through Friday night with a chance for a few strong storms east of I-71 Thursday 1 - 8 PM.

2) Heat and humidity returns next week with heat indices possibly exceeding 100 degrees, especially in Northwest Ohio.

DISCUSSION

KEY MESSAGE 1... Low pressure moves into the Great Lakes region tonight with residual convection moving in from the northwest late tonight through Thursday morning. This will mainly be rain showers with a few embedded storms.

Additional convection will develop Thursday afternoon, mainly east of I-71. Sufficient instability and deep-layer shear will be present for marginally organized convection during the afternoon with a few strong to severe storms. Severity will likely depend on prevalence of morning convection.

Another low moves up from the southwest, with an additional round of showers and thunderstorms Friday through Saturday morning. Model guidance has trended later with precipitation onset on Friday, and there is a chance that most of Friday is dry. Precipitation is most likely for southern counties.

KEY MESSAGE 2... An upper-level ridge builds into the eastern CONUS, with heat and humidity building into the local region next week. The latest NBM has Tuesday and Wednesday as the hottest days of the week with >50% probability of 90 degrees and heat indices > 100 degrees. There are very low probabilities of thunderstorms each day (around 10- 30%), greater towards the east and best chance is on Wednesday.

AVIATION /06Z Thursday THROUGH Monday/

Shower activity will approach from the west early this morning and continue to spread east during the overnight hours. Overall, rain is mostly VFR in Indiana and NW OH with just some minor pockets of MVFR in the most potent showers. With low confidence in MVFR, have just VFR with the first wave of rain into Thursday daytime hours. The main concern for today will be the development of thunderstorm clusters this afternoon over NE OH and NW PA. The biggest factor in new activity this afternoon will be how worked over will the region be after this morning's rain and clouds and can any new activity form over the airspace before the front moves through. Areas out west, including KTOL and KFDY, appear to be in the clear with poor timing for new development. Whereas, areas further east, including KCAK and KYNG, are trending more concerning for getting afternoon thunderstorms. Therefore, will have PROB30s for thunderstorms at KMFD and KCLE and will up the concern for KCAK, KYNG, and even KERI to TEMPO for thunderstorms with the potential for IFR this afternoon. Behind the front, rain will clear out and conditions will return to VFR with light westerly winds.

Outlook...Non-VFR possible in showers and thunderstorms Friday afternoon through Friday night with some lingering activity potentially continuing into Saturday.

MARINE

With the exception of some stronger wind gusts associated with thunderstorms Thursday afternoon and evening, particularly across the eastern basin of Lake Erie, generally quiet marine conditions are expected through the weekend. Winds will shift towards the south to southwest on Thursday, 10 to 15 knots, becoming north to northeast behind a cold front on Friday into Saturday, 10 to 15 knots. Onshore, northeast flow will then continue through Sunday, around 10 knots.

CLE WATCHES/WARNINGS/ADVISORIES

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