textproduct: Cleveland

WHAT HAS CHANGED

Confidence is increasing for a prolonged wet pattern across the region beginning on Saturday.

KEY MESSAGES

1) Showers and thunderstorm chances will gradually diminish across the area through tonight as a cold front moves through the area.

2) Unsettled weather returns for the weekend and into early next week. Heavy rainfall and localized flooding are possible, especially Saturday into Sunday.

DISCUSSION

KEY MESSAGE 1... The latest radar and satellite imagery reveal a decaying complex of showers and storms across portions of Northwest and North-Central Ohio this afternoon, with that trend expected to continue over the next several hours as a weak downstream thermodynamic environment remains in place. Meanwhile, surface observations indicate a surface cold front in Michigan which will continue to move south across the area by later this evening and overnight. Most of the area will largely remain dry behind this afternoon's precipitation, though shower and storm chances may increase again for a tier or two of counties across the southwest (Findlay to Mount Vernon) as a shortwave tracks along the front overnight.

High pressure will build south across the Great Lakes following the cold front on Friday, leading to mainly dry and pleasant weather.

KEY MESSAGE 2... Unsettled weather will return beginning on Saturday and could persist through early next week. Low pressure will lift a warm front north across the Ohio Valley on Saturday, before it stalls in the vicinity of the Lower Great Lakes. A couple of mid- level shortwaves will track east along the front late Saturday through Sunday which will result in periodic showers and storms, the most widespread of which should occur Saturday night into Sunday morning. Heavy rain appears to be the main threat with tall, skinny CAPE profiles and anomalously-high PWATs.

The latest upper-level guidance suggests that the active weather pattern will continue through the early part of next week as several disturbances move through or impact the area. This includes a weak upper-level low on Monday, followed by a shortwave and residual troughing by Tuesday and Wednesday. Periods of mainly rain will occur during this timeframe, though can't rule out some isolated thunderstorms with pockets of elevated instability. Areal flooding concerns will continue to increase through the weekend and into early next week and will need to be monitored.

AVIATION /00Z Friday THROUGH Tuesday/

MVFR/IFR stratus will become dominant once again overnight in the wake of a cold front that is finally working its way south of the region. In the low level northerly flow behind the cold front, this stratus will take several hours into Friday morning/early afternoon for the stratus to finally scour/erode out. SCT flat cumulus field FL035-045 into the afternoon hours Friday. Winds northeasterly could briefly eclipse 12kts after 17Z.

Outlook...Non-VFR possible with showers and thunderstorms Saturday through Sunday.

MARINE

Brief rough conditions will return across Lake Erie late tonight into Friday morning as a cold front ushers in northeast winds of 15 to 20 knots. Given the brief nature of 3 to 4-footers, opted against a Small Craft Advisory at this time. Winds will gradually diminish into Friday afternoon as high pressure builds south across the Great Lakes. Winds will then shift towards the east on Saturday ahead of a warm front, 10 to 15 knots, becoming northeast and increasing into the 20 to 25 knot range Sunday night as a stationary front settles just south of Lake Erie. Northeast winds will increase further into the 25 to 30 knot range Monday into Tuesday as the pressure gradient increases between surface troughing and high pressure to the north. Can't rule out brief Gale-Force gusts during this timeframe, though at this time, the potential for a more prolonged period of Gales appears low.

CLE WATCHES/WARNINGS/ADVISORIES

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