142 FXUS61 KCLE 100927 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 427 AM EST Sun Nov 10 2019 .SYNOPSIS... A cold front will move southeast across the area this afternoon and become nearly stationary. An Oklahoma Panhandle hook low pressure system will develop and move quickly northeast along the stationary front into the Ohio Valley by Monday evening. The low pressure system will move northeast to Maine by Tuesday evening drawing Arctic air south across the local area. High pressure will build east over the local area by Wednesday. && .NEAR TERM /THROUGH MONDAY/... Big changes will arrive over the local area in the next 36 hours. An upper level trough will dive into the eastern half of the United States through Wednesday causing a Panhandle Hook low pressure system to develop over Oklahoma. Meanwhile, a weak cold front is progged to move southeast across the local area this afternoon where it will become nearly stationary. The front is poised to bring some limited moisture to the local area late this afternoon and tonight along with an upper level positive vorticity maximum. The features all appear to be out of phase with one another compared to yesterday so this could limit precipitation chances to mostly tonight rather than this afternoon. More moisture will stream in from the west and southwest to the area late tonight into Monday in advance and with the low pressure system. Also, Arctic air is expected to plunge south in the wake of the low causing the precipitation to become mixed with and then change over to snow from west to east Monday. 850 mb 0 degrees pushes southeast of the forecast area by Monday evening. Thermal profile suggests possibility that some sleet could mix in during the change over to snow. Expecting accumulating snow in the northwest quad of the low pressure system that will affect all areas. Initially, this is not a lake effect snow event since all areas will be impacted. Eventually, the snow will transition to lake effect beyond Monday. Some warming will take place today ahead of the cold front to the upper 40s to around 50 degrees. Cold air advection will take place tonight from west to east slowly with the passage of the low pressure system. Monday's highs will likely be during the morning or early afternoon and begin to fall through the afternoon and evening. Drastically colder temperatures on the way through mid week. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... A large and deep upper level trough will be moving across the northern U.S. and Great Lakes Region. Widespread light to moderate snow will be on going across the area Monday evening. Snowfall accumulations will be easier after sunset and temperatures continue to fall below freezing. The evening commute will likely have some impacts and the heaviest QPF with the synoptic system will be between 00z and 06z. The storm system pulls away from the region by Tuesday morning with the synoptic snow ending from west to east between 06z and 12z. Expected snowfall with just the synoptic storm system will average about 1 to 2 inches down south closer to central Ohio and about 2 to 5 inches further north closer to the lakeshore. There are some indication that there could be local enhanced area of convergence and a heavier band somewhere near the Cleveland area. The NAM, 4KM WRF, and GFS have been showing this potential and will continue to monitor that trend. At this time, we will hold off on any winter hazard headlines but there is the possibility that we may need to issue headlines by this afternoon. The lake effect snow machines become alive and cranking by Tuesday morning as very cold air for this early in the season spills across the Great Lakes region on Tuesday. 850 mb temperatures drop to -18C and lake induced CAPE values approach 1000 J/KG with extreme localized instability. Giving the north to northwest flow and small interruptions in the flow, it likely we will see multiple bands develop over the lake as well as a Lake Huron connection on Tuesday into Tuesday night. The primary and secondary snowbelt areas will see lake effect snow most of the day Tuesday into Tuesday night. There will likely be at least several inches expected with localized heavier or significant snowfall if a stronger band can develop and stay over that location. Some thundersnow is possible as well given the extreme instability. The lake effect snow will slowly wind down and drift off to the east into southwest New York by Wednesday afternoon. We will see very cold temperatures and likely record breaking cold on Wednesday morning with temperatures in the lower to middle teens. && .LONG TERM /THURSDAY THROUGH SATURDAY/... The temperatures will moderate for the end of the week as southerly winds return on the back side of the high pressure system. A fast clipper like system will move across the region very early on Thursday with light rain or light snow showers. Westerly flow over the lake late Thursday into Friday may allow for the potential for additional lake clouds and lake effect light showers affecting far northeast Ohio into northwest Pennsylvania. && .AVIATION /06Z Sunday THROUGH Thursday/... A cold front will move southeast across the local area later this afternoon with a weak wave of low pressure moving northeast along the front. Moisture associated with the front will move into the region and bring with it a chance for some rain or a mix of rain and snow across portions of the area. Ceilings will be dropping with time across the area as the front approaches. Some visibilities will drop to mostly MVFR but brief periods of IFR are possible. .OUTLOOK...Non-VFR likely through Monday night with widespread precipitation. Non-VFR expected Tuesday and Wednesday with lake effect snow showers. Non-VFR possible Wednesday night into Thursday all areas. && .MARINE... There will be southwest winds 10 to 20 knot on the lake today but a cold front will be move across the lake tonight. The winds will shift to northerly by this evening. Low pressure develops over the Ohio Valley and moves northeast along this boundary on Monday and to the New England Coast on Tuesday. As a result of this developing low pressure, northeast wind of 15 to 25 knots will develop starting Monday. Northwest winds of 15 to 25 knots will develop on Tuesday as a result of the low pressure moving off to the northeast. This will result in Small Craft Advisory conditions across much of Lake Erie until winds diminish by Wednesday afternoon. High pressure will move over the lake on Wednesday with lighter winds. Southerly winds 10 to 15 knots will return on the lake by Thursday. && .CLIMATE... Arctic air will move southeast into the local area Monday night into Tuesday and then begin to shift east Tuesday night. The unseasonably cold air will cause temperatures to plummet to some of the coldest readings so far this season. Below are the coldest temperatures on record for selected dates at our six climate sites: Tuesday, November 12: Coldest high (year) Coldest low (year) Akron-Canton Area: 28 (1920) 16 (1950) Cleveland Area: 31 (1920) 18 (1911) Erie Area: 34 (1996) 18 (1911) Mansfield Area: 29 (1996) 16 (1976) Toledo Area: 30 (1995) 15 (1976) Youngstown Area: 30 (1996) 19 (1950) Wednesday, November 13: Coldest high (year) Coldest low (year) Akron-Canton Area: 25 (1911) 12 (1911) Cleveland Area: 22 (1911) 15 (1911) Erie Area: 23 (1911) 16 (1911) Mansfield Area: 27 (1986) 13 (1986) Toledo Area: 22 (1986) 13 (1911) Youngstown Area: 29 (1996) 17 (1986) && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. MARINE...None. && $$ SYNOPSIS...Lombardy NEAR TERM...Lombardy SHORT TERM...Griffin LONG TERM...Griffin AVIATION...Lombardy MARINE...Griffin CLIMATE...