textproduct: Cleveland

WHAT HAS CHANGED

Drizzle and mist is expected to linger longer this evening into tonight. Record high temperatures are looking increasingly likely Tuesday.

KEY MESSAGES

1) The remnants of Isaias will move away this evening, but drizzle and mist will linger through the first half of the night, along with areas of fog.

2) Record high temperatures are likely Tuesday ahead of a cold front that will bring showers and thunderstorms Tuesday night into Wednesday.

3) Briefly drier Wednesday night into Thursday before a strong cold front brings rain, gusty winds, and the coldest air of the season Friday into Saturday.

DISCUSSION

KEY MESSAGE 1... The remnant low of Isaias is centered over West Virginia this afternoon, while a weak mid/upper trough axis that has been helping to steer the remnants is centered over the southern Great Lakes and Ohio Valley. As the trough axis progresses east tonight, the remnant low will be transported east into the Mid Atlantic region before exiting offshore Monday morning.

The bulk of the rain has shifted into central PA, but abundant low- level moisture and some PVA from the mid/upper trough overhead is keeping bands of light showers and drizzle from north central Ohio through NE Ohio and NW PA. This light shower activity and drizzle will gradually pivot east this evening and tonight, but given the amount of low-level moisture lingering beneath the trough axis, feel that drizzle will be stubborn to end even after the actual rain showers end. Trended the forecast toward longer periods of drizzle and mist gradually ending from west to east through 06Z tonight, but low clouds and patchy fog are likely all night. Drying of the boundary layer in the wake of the trough should gradually break up the low clouds Monday morning, and expect increasing sunshine by afternoon as mid/upper ridging expands over the central and eastern CONUS and surface high pressure strengthens across the Appalachians and SE CONUS in response to deep mid/upper troughing progressing further into the western CONUS. This will set up increasing warm air advection to boost highs well above normal Monday afternoon, with upper 70s/low 80s in NW Ohio and low/mid 70s in NE Ohio and NW PA.

KEY MESSAGE 2... The warmth that starts Monday afternoon will really peak Tuesday as the mid/upper ridge further amplifies over the eastern CONUS ahead of the western trough evolving into a closed low near the Four Corners region. Strengthening warm/moist advection and isentropic ascent combined with a mid/upper shortwave and surface low crossing the central Great Lakes could drive a few showers north of a retreating warm front Monday night into early Tuesday morning. These could brush the lakeshore counties of northern Ohio and NW PA, but the bulk of any rain should be over Lake Erie and southern Ontario. Impressive warmth is likely in the warm sector Tuesday afternoon, with probabilities increasing for record highs in parts of the region as temperatures reach the mid 80s in NW and north central Ohio and upper 70s/low 80s in NE Ohio and NW PA. The best chance to exceed the records will be at KTOL and KCLE. See climate section for details.

The ridge will start to flatten Tuesday evening and night as a northern stream mid/upper trough drops across the central and eastern Great Lakes. This will push a cold front slowly south into the area Tuesday night, but the front will become quasi-stationary late Tuesday night into Wednesday morning as the combination of strong ridging to the south and energy emanating out of the Four Corners closed low riding the boundary holds it up. A few showers and thunderstorms could occur late Tuesday afternoon and evening in NE Ohio and NW PA as forcing increases ahead of the approaching shortwave and 110+ knot jet, but the bulk of the rain will occur late Tuesday night into Wednesday as the boundary gradually sags south and the energy from the west rides along it. The sagging front and precip will keep temperatures cooler Wednesday, with highs in the upper 60s/low 70s north and low/mid 70s south.

KEY MESSAGE 3... The front will briefly push into the Ohio Valley Wednesday night and early Thursday as Canadian high pressure ridges down from the Upper Great Lakes leading to seasonably cool and drier conditions. However, the front will quickly lift back north as a warm front late Thursday and Thursday night ahead of a potentially significant storm system. The old Four Corners cut off low will attempt to phase with a strong northern stream mid/upper trough diving into the northern Plains and Upper Midwest Thursday night and Friday, resulting in a rapidly deepening surface low crossing the Lower Great Lakes Friday and strong cold frontal passage. There remains uncertainty on the strength of this system and resultant push of cold air in its wake due to differences in how much the northern stream trough can phase with the old cut off low, but ensemble guidance and general pattern recognition suggests at least a seasonably strong Fall storm system and the coldest air of the season so far. Widespread rain is likely Friday followed by falling temperatures late Friday into Saturday and lingering lake effect showers. Depending on the strength of this system, wind headlines are certainly possible. Slow moderation by Sunday.

AVIATION /18Z Sunday THROUGH Friday/

In terms of rain, some showers continue across the far eastern end of the area, including in the vicinity of YNG. These showers will continue to gradually exit east, with some patchy mist or drizzle then persisting through the remainder of the afternoon and into tonight as the low-levels remain moist. The main restriction is and will continue to be ceilings with IFR or MVFR across the board, though any showers or patchy mist/drizzle can bring some passing visibility restrictions too. Ceilings may bounce around at times, but in general will remain IFR to low MVFR into Monday morning. Guidance suggests ceilings will generally lower some tonight as a trough axis and wind shift pivot east across the area and as the sun sets. Ceilings should quickly climb and mix out later Monday morning and into the afternoon as much drier air works in.

Winds range from east-northeast in Northwest OH to southeast elsewhere this afternoon. Winds are expected to gradually shift more north-northwest into tonight and then west-southwest on Monday. Winds should remain 10 knots or less.

Outlook...Non-VFR possible Tuesday and Wednesday in showers/ thunderstorms associated with a cold front.

MARINE

Winds on Lake Erie will continue to veer NE this evening then NW tonight while decreasing to under 5 knots as the remnants of Isaias pull away. SW winds will then increase to 10-15 knots by late Monday as a low pressure system crosses the central Great Lakes and warm front lifts across the lake. These SW winds will further increase to 15-20 knots Monday night and Tuesday until diminishing behind a cold front Tuesday night and shifting NW. Light winds early Wednesday will gradually give way to stronger N winds of 10-15 knots Wednesday afternoon, turning NE at 15-20 knots Wednesday night and Thursday as high pressure builds across the Upper Great Lakes.

After a brief lull in winds, a strong storm system looks to impact the Great Lakes Friday into Saturday. Gales are possible with this system, but there remains uncertainty on the exact track and strength which will be monitored in 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.