textproduct: Cleveland

WHAT HAS CHANGED

Minimal changes made to the forecast with this package.

KEY MESSAGES

1) There will be a chance for thunderstorms as a warm front lifts north across the region tonight. A few storms could produce strong gusts upwards of 50 MPH.

2) A cold front will sweep through the region early Friday as low pressure moves through the Great Lakes bringing the chance for rain and gusty winds.

3) Coldest air of the season is expected Friday night and Saturday night with frost/freeze conditions expected on Sunday morning.

DISCUSSION

KEY MESSAGE 1... Low pressure will move northeast through the Great Lakes region this evening. A warm front will lift northeast across the local forecast area this evening into the overnight hours. Showers with isolated thunderstorms are expected to enter the area from the west with the warm front this evening. There will be minimal instability (~500 J/kg) but plenty of bulk shear given a strong low level jet of 40-50 knots with the warm front. The potential for an isolated strong storm capable of producing a localized 50 MPH or greater wind gust, particularly across Northwest and North Central Ohio. SPC has maintained this area in their SWODY1 outlook. The potential for any strong to severe storm will diminish through the overnight hours as instability wanes.

KEY MESSAGE 2... A cold front will glide east through the morning hours on Friday as the aforementioned low continues to lift northeast across the Lower Great Lakes. Latest hi-res guidance show a line of showers and thunderstorms redeveloping east of I-71 after sunrise on Friday along and ahead of the cold front. The line of showers and scattered storms will exit to the east across noon on Friday but expect for lingering lake enhanced showers to linger through Friday night downwind of the lake as a surface trough drapes itself across the local area. Overall rainfall amounts with range between 0.25-0.50" with the highest amounts confined to Northwest Pennsylvania and the Cleveland metro given the longer duration lake enhanced rainfall with a Lake Huron connection. Locally higher rainfall possible in any thunderstorm.

In addition to rainfall, winds and gusts will increase with the frontal passage in the CAA regime. Strong southwesterly winds will peak at 15-20 MPH with gusts up to 25-30 MPH in the early morning hours on Friday. The strongest winds are expected across Northwest Ohio and along the lakeshore. Winds will turn northerly by Friday night but remain elevated before high pressure builds overhead on Saturday and winds decrease.

KEY MESSAGE 3... A much cooler airmass will be in place behind the cold front as temperatures Friday night into Saturday morning fall into the mid 30s. The frost potential remains limited given strong wind speeds, lingering rain showers and persistent cloud cover. By Saturday night, lows fall into the low 30s across much of the forecast area with a mainly clear sky under high pressure. The probabilities for frost remain high outside of locations near the lakeshore given the relatively warm waters.

AVIATION /00Z Friday THROUGH Tuesday/

Showers will continue to progress east and northeastward into all terminals over the next 3 hours ahead of a warm front. The only terminal that remains VFR is KERI, but expect that site to fall to MVFR by 02Z. This will lead to frequent rain showers overnight and MVFR cigs and vis, with eventually some IFR around the pre-dawn hours. Periods of showers will continue Friday in the wake of a strong cold front that will cross the region in the morning. This will keep conditions MVFR, and briefly lower in heavier showers. KTOL, KFDY, and KMFD will try to dry out in the late afternoon and evening, but lake enhancement will keep showers going farther east.

Light SE winds this evening will turn SW and increase to 15-20 knots over the next 6 hours. Low-level wind shear is possible as the winds first increase above the surface, especially at KTOL, KFDY, KMFD, and KCLE where a low-level jet noses overhead. By the pre-dawn hours, surface gusts should reduce low-level wind shear. Winds will quickly veer west late tonight and Friday morning in the wake of the cold front, with W winds of 15-25 knots gusting to 30 knots at times through Friday afternoon. Winds will eventually turn NW and slowly diminish Friday evening.

Outlook...Occasional non-VFR expected to continue in periods of rain showers and lower ceilings through Friday night. Winds may gust over 30kt at times through early Saturday.

MARINE

East winds 10-15 knots will turn become southwesterly while increasing to 20-25 knots as a warm front lifts northeast across the lake this evening. A cold front will sweep east across the lake Friday morning leading to winds turning northeasterly by late Friday afternoon. Wave heights will build to 5-10 feet during this time frame. A secondary trough will remain draped across Lake Erie Friday night which will lead to winds to shift northerly around 25-30 knots with waves of 8-11 feet. Small Craft Advisories for the entire lake have been issued from tonight through Saturday morning. High pressure builds into the region on Saturday allowing for winds to decrease and wave heights to subside through the daytime hours. Winds 10-15 knots turn southwesterly and continue through Monday.

CLE WATCHES/WARNINGS/ADVISORIES

OH...None. PA...None. MARINE...Small Craft Advisory from 2 AM Friday to 11 AM EDT Saturday for LEZ142-143-149. Small Craft Advisory from 2 AM Friday to 4 PM EDT Saturday for LEZ144>148.