textproduct: Cleveland

WHAT HAS CHANGED

The axis of heavier rain with this system has trended to the east and forecast rain amounts will be much lower for today. Removed the mention of thunderstorms for today.

KEY MESSAGES

1) Rain amounts associated with the remnants of Isaias have trended much lower. No significant impacts from this system are expected in the local area today.

2) Near record high temperatures are forecast for Tuesday ahead of a cold front. The front will bring a chance of showers and thunderstorms Tuesday afternoon and evening for eastern portions of the area.

3) A strong cold front will bring the coldest air of the season on Friday. Some locations may experience the first fall freeze over the weekend.

DISCUSSION

KEY MESSAGE 1... The remnant low associated with Isaias has taken a track that is farther to the east than previously forecast, through eastern Tennessee towards the Central Appalachians. The axis of deep moisture is to the east of the track and is primarily focused across West Virginia and Pennsylvania which is where the heavier rain is going to occur. Rainfall overnight has been quite light, with a quarter inch or less and many areas receiving a tenth of an inch or less. Areas located east of I-77 could still see an additional half inch of rain while amounts are going to range from 0.10-0.25 elsewhere. The upper level closed low is displaced to the west of the surface low and will track northeast through the Ohio Valley today. This will maintain some shower activity but dry air in the mid levels will be a limiting factor and cut-back significantly on rainfall amounts. Also removed thunder for today as we have seen only one strike south of our area overnight. A minimal amount of elevated instability remains in our southern counties but the better forcing continues to shift east.

Some locations across northeast Ohio and Northwest pennsylvania are starting to see winds gusting around 20 mph where the gradient is the tightening up. We still believe a few stronger gusts could occur for northern portions of Erie Pennsylvania where the southeasterly wind direction is favorable for enhanced downsloping. Gusts of 30-40 mph remain possible through mid morning. Abundant cloud cover is expected today and temperatures will peak in the 60s.

KEY MESSAGE 2... An upper level ridge quickly builds north behind the departing trough on Monday. At the surface, a ridge will build east across the area with southwesterly winds and warm advection kicking in across Northwest Ohio during the afternoon. Highs on Monday range from about 70 in the east to 80 in the west. The anomalously warm airmass airmass with 850mb temperatures of nearly 20C will be in place on Tuesday ahead of a cold front settling south across the region. Highs on Tuesday may tie or surpass multiple records across Northwest and North Central Ohio. See the climate section below for details.

Chances of rain have slowed down on Tuesday with a slight chance across Lake Erie Tuesday morning and then pushing inland late Tuesday as a shortwave moves through the flow aloft and pushes a cold front south of Lake Erie late afternoon and evening. Chances of thunderstorms look focused across Northeast Ohio and Northwest Pennsylvania. Some minimal instability is forecast to develop ahead of the front with dewpoints in the lower 60s. May need to keep an eye on any thunderstorms that can develop given a stronger wind field with shear in the 0-6km layer of 45-55 knots.

KEY MESSAGE 3... By late this week, models are in agreement that a strong trough will drop south out of Canada ushering in the coldest air of the season. The front looks to arrive on Friday with cold air filtering into the region through Saturday. There are some noteworthy differences in the long range pattern by the weekend as the ECMWF does not phase the Canadian trough with an upper level low moving out of the Rocky Mountains and is more progressive with the colder air quickly shifting east. The 00Z GFS and Canadian both indicate there will be phasing with the upper low which results in a slower trough and perhaps lake effect precipitation. Will need to monitor trends as large spreads currently exist in temperatures based on timing. It is possible that we could see frost and freeze conditions next weekend, especially if high pressure ends up overhead on Saturday night.

AVIATION /12Z Sunday THROUGH Thursday/

MVFR and IFR ceilings have moved in from the south this early this morning. Ceilings will become IFR at all terminals by mid morning and persist through the TAF period. Scattered rain showers are expected from KMFD eastward and will taper off west to east through the afternoon. Lingering drizzle and mist may lower visibility this evening. After 06Z tomorrow, patchy fog is possible for KMFD, KTOL, and KFDY though will be conditional on how quickly ceilings clear out. Confidence is low in visibility less than 2SM impacting terminals.

Winds will be out of the east, 080-130, at 8-13 knots across the region into the morning before weakening to around 5-10 knots. KERI will have a more of a southeasterly, 130-150, wind and with downsloping, could see gusts upwards of 20 knots through 17Z. Winds will gradually back to be out of the northeast, 020-050, during this afternoon and remain 5-10 knots. After 00Z, winds will shift to be more northwesterly, 310-340, and weaken to less than 5 knots.

Outlook...Non-VFR expected in low ceilings Sunday night into Monday, with improving conditions from west to east throughout Monday. Non-VFR possible Tuesday and Wednesday in showers/thunderstorms associated with a cold front.

MARINE

Southeast winds are starting to increase in the nearshore waters from Avon, OH to Ripley, New York with speeds of 15-25 knots. The window of stronger winds will be short lived and expect to be able to let the Small Craft Advisory expire as planned at 8 AM this morning. Winds shift around to the northeast later today but are expected to generally be light.

Two cold front are expected to cross Lake Erie this week with impactful conditions. The first is on Tuesday evening when a cold front with winds of 15-20 knots shifts onshore. Waves of 2 to 5 feet will be possible for a few hours behind the front on Tuesday night and a Small Craft Advisory may be needed east of Geneva-on-the-Lake. By late this week, a much stronger cold front looks to cross Lake Erie in the Friday time frame. Winds are forecast to reach 30 knots with potential for a gale event. The strength and track of this late week system will be monitored over the coming days.

CLIMATE

Temperatures are forecast to be near record high values across Northwest and North Central Ohio on Tuesday. Records for October 13 are listed below for the official climate locations.

Date Toledo Mansfield Cleveland Akron Youngstown Erie

10-13 83(1975) 84(1969) 82(1969) 82(1969) 83(1969) 83(1983)

CLE WATCHES/WARNINGS/ADVISORIES

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