541 FXUS61 KBTV 171932 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 332 PM EDT Tue Mar 17 2020 .SYNOPSIS... Rain and snow showers will be coming to an end across the North Country this evening and skies are expected to clear overnight. High pressure centered over the region on Wednesday will bring sunshine and high temperatures slightly above normal. A fast moving low pressure system will track to our south late Wednesday night into Thursday and bring additional precipitation to the area...some of which will be in the form of snow along with light snow accumulations. A noticeable warming trend takes place Thursday into Friday with highs in the 60s on Friday. However...widespread rain is also expected for Friday. Colder and drier weather is expected for the weekend as high pressure builds into the region. && .NEAR TERM /THROUGH WEDNESDAY NIGHT/... As of 332 PM EDT Tuesday...Last of the more widespread rain and snow is exiting the area and we are left with some light showers upstream. Thus looking at a decreasing trend of precipitation over the next several hours with precipitation ending around midnight. Based on satellite trends that is when we should see the areal coverage of clouds noticeably decrease. This will allow low temperatures to fall into the 20s tonight. Looking at a nice day on Wednesday with high pressure over the area. Should be a good deal of sun, no precipitation, and highs in the upper 30s to mid 40s. Clouds will be on the increase Wednesday night as a relatively fast moving low pressure system tracks just to our south. Precipitation should become widespread over the area with southern areas having the best chance for precipitation. With temperatures in the lower to mid 30s looking at precipitation in the form of snow and we should see an inch or less over the far northern sections of the area, but looking at 1 to 3 inches across central and southern Vermont by Thursday morning. Will need to keep an eye on the Thursday morning commute, which may be impacted across our southern areas. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... As of 332 PM EDT Tuesday...Upper shortwave will begin sliding east of the North Country on Thursday. High pressure will still be exerting some influence over the region Thursday with blocked easterly flow. Anticipate temperatures to initially struggle to rise on Thursday, but not at the sluggish rates in the 12Z NAM output. Areas west of the Greens will slowly transition to a rain/snow mix and then rain as warmer air and higher thicknesses slowly move into the region, except for some areas of the eastern Adirondacks. In that small pocket of the Adirondacks and east of the Greens, there could be some sleet or freezing rain that may try to briefly mix in before precipitation largely moves out. Deep layer saturation becomes lacking, but there is still plenty of low-level moisture and warm advection, so have advertised a slight chance to chance of drizzle as the previous forecaster had done. Once the system moves out of the region, upper ridging to our south will continue to expand northwards, so temperatures should warm more readily once precipitation has ended. Forecast highs are around 40 east of the Greens and in the mid to upper 40s west of the Greens. Overnight, temperatures will be slow to fall as a strong warm front quickly lifts northwards. Frontogenetical forcing is quite strong with strong isentropic upglide lending itself to a period of moderate to heavy precipitation overnight Thursday. PWATs rise above the 90th percentile of climatology reaching values of about 1". Temperatures remain in the 40s west of the Greens and fall into the mid 30s east of the Greens. && .LONG TERM /FRIDAY THROUGH TUESDAY/... As of 332 PM EDT Tuesday...The extended period of the forecast begins with the North Country firmly in the warm sector. Strong warm advection will send temperatures into the 60s. A 50-60kt LLJ at 850mb will efficiently move warm frontal precipitation north of our region, leaving us with scattered showers ahead of a prefrontal trough and strong cold front to push through later on Friday. Before the front arrives, the potential exists for some gusty winds to mix to the surface. Will continue to watch trends, as the potential for more stable air to prevent mixing appears possible. For now, have mentioned 30-35 knot gusts in the St. Lawrence Valley. Similar to the warm front, this cold front will be rather strong, with about 100-250 J/kg of CAPE available, along with strong FGEN forcing due to a strengthening baroclinic zone along the axis of the front. Anticipate most of the precipitation to occur ahead of the front. Decided to place a slight chance of thunder for the St. Lawrence Valley. When taken together with the precipitation associated with the warm front precipitation amounts should be in the ballpark of 0.4"-0.8". Given the sharp nature of the cold front, the arrival of below freezing temperatures will be watched closely. Much quieter for the remainder of the extended period with an expansive surface high keeping us seasonably cool for a few days and then gradually moderate as it progresses eastwards. The next chance for precipitation should be around mid-week, perhaps Tuesday, but synoptic models disagree on progression of the next system. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... Through 18Z Wednesday...Rain and snow showers will be coming to an end by 00z. Visibilities will generally be in the VFR category...but may lower into the MVFR category through 00z. With no precipitation expected for the remainder of the period visibilities will remain in the VFR category. Ceilings will mainly be in the VFR and MVFR categories through about 06z before cloud cover becomes scattered for the remainder of the period. These clouds will be in the VFR category. Gusty south to southwest winds will continue through 00z with gusts in the 20 to 30 knot range. Winds after 00z will generally be from the west at speeds of 10 knots or less for the remainder of the period. Outlook... Wednesday Night: VFR. Chance RA, Chance SN. Thursday: Mainly MVFR, with areas VFR possible. Chance RA, Chance DZ. Thursday Night: Mainly MVFR, with local IFR possible. Definite RA, Chance DZ. Friday: MVFR/IFR conditions possible. Windy with gusts to 30 kt. Definite SHRA. Friday Night: Mainly VFR, with areas MVFR possible. Chance SHRA, Slight chance SHSN. Saturday: VFR. NO SIG WX. Saturday Night: VFR. Chance SHSN. Sunday: VFR. NO SIG WX. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Evenson NEAR TERM...Evenson SHORT TERM...Haynes LONG TERM...Haynes AVIATION...Evenson