Area Forecast Discussion
Issued by NWS Burlington, VT
Issued by NWS Burlington, VT
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210 FXUS61 KBTV 231407 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 907 AM EST Sun Nov 23 2025 .SYNOPSIS... Light snow will spread from west to east today producing minor accumulations, then tonight into Monday morning precipitation will become terrain-driven in northwesterly upslope flow supporting more snowfall in the mountains. A warm front will bring light rain late Tuesday and provide above normal temperatures into Wednesday. Then a cold front will bring more showers on Wednesday followed by cooler weather for Thanksgiving Day, when lake-effect snow and breezy conditions are expected. && .NEAR TERM /THROUGH MONDAY/... As of 906 AM EST Sunday...Have made an update to increase PoPs since we already seeing snow this morning across the Champlain Valley. Also increased winds and wind gusts at highest elevations and decreased hourly Ts to better match observations. Previous discussion...A thermally-weak clipper system is bringing light snow today. Snow will overspread our area this morning, resulting in light accumulations through noon almost certainly across northern New York, as far east as our western Clinton and western Essex County zones. The western Champlain Valley will be more questionable with the first snow flakes probably beginning late morning and not accumulating more than a dusting. During the afternoon, light snow will then begin to accumulate across Vermont, with measurable snow likely (~50-90% chance) by 5 PM. Lowest elevations in the Champlain Valley and Upper Valley have sharply lower probabilities of seeing snow accumulate. While no significant changes were made to the snowfall forecast, it is a pretty challenging one with regards accumulation in valley locations. With marginal temperatures and daytime occurrence, precipitation type and amount uncertainty are noteworthy; light precipitation rates make it difficult to overcome above freezing surface temperatures. That being said, predictability of snow versus rain has become increasingly well defined, with a strong consensus showing surface wet bulb temperatures rising above freezing in the St. Lawrence Valley by around noon, supporting all rain after that time following widespread snow accumulations up to 0.5". In the Champlain Valley, near Lake Champlain in the very lowest elevations wet bulb temperatures also point to mainly rain, but with just slight elevation gain we`ll have more of a rain/snow mix, beginning as snow and becoming more likely to mix with rain with time as temperatures slowly increase. Again, precipitation type looks strongly driven by elevation areawide especially due to afternoon timing in Vermont, such that a mix of rain and snow for instance is possible across the Winooski and White River valleys and near I-91, when precipitation is particularly light, but would tend to favor snow in steadier precipitation. Then tonight we`ll switch gears into an upslope snow event as favorable 310 degree wind direction in the 925-850 millibar layer will develop on the backside of the clipper with increasing wind speeds. Magnitudes are a little lighter than what one would want to see for heavy upslope snow, but moderate snowfall rates are possible, especially at the summits where snow ratios will be substantially higher given relatively mild air. Temperatures in the western slopes will be near freezing with minimal cool air advection, but blocked flow and very moist profiles with just enough saturation in the snow growth zone look favorable for up to a few inches of wet snow accumulation in localized areas, but mainly under an inch of new snow tonight is expected. Some snow showers will linger into tomorrow morning, with otherwise quiet weather as surface and upper level ridging moves across our region. Low level thicknesses climb substantially in response and surface temperatures should in kind rise well above freezing with upper 30s to low 40s common for highs. && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY/... As of 223 AM EST Sunday...A couple of frontal systems, one passing to our north and another approaching from the southwest, will bring abundant cloudiness through this period but it will mainly be dry through midday Tuesday. During the afternoon precipitation chances start to increase from southwest to northeast, although most model guidance shows precipitation holding off until Tuesday night. Aside from the high terrain and Lake Champlain, winds will remain fairly light as the pressure gradient ahead of the incoming low pressure system (roughly a 1005 millibar low against a 1025 millibar high to our east) looks meager. The weak thermal advection will boost temperatures a bit from recent days, with highs probably in the low to mid 40s in most spots. Depending on cloud cover thickness Monday night, low temperatures currently forecast may be a bit too cold, but morning temperatures are most likely to be near or below freezing to start the day. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... As of 133 AM EST Sunday...Seeing better overall NWP consensus for the mid-late week period, highlighted by mild temperatures for Wednesday, followed by cooler and breezy conditions for Thanksgiving Day with scattered rain/snow showers likely. Continues to appear that leading shortwave trough and associated surface warm front bring widespread light rain to the region during Tuesday night. May see a brief rain/snow mix over Vermont`s Northeast Kingdom at the onset of precipitation, but not expecting any snow accumulation as temperatures generally hold in the mid- upper 30s overnight and into the pre-dawn hours Wednesday. PoPs generally in the 70-80% range with rainfall amounts of 0.25 to 0.40" likely in most locations from the Adirondacks eastward across VT (may see slightly less rainfall in the St. Lawrence Valley based on current indications). Best synoptic forcing lifts to our north and east for Wednesday, but appears low-level moisture/cloud cover will generally hold in place. Looking for mostly cloudy skies, light to moderate S to SW winds and high temperatures expected in the upper 40s to lower 50s. If we reach 50F at BTV, it will be the first 50 degree day since November 8th. A deep, vertically stacked low pressure system lifts from the northern Great Lakes region into nrn Ontario/swrn Quebec for Wednesday night into Thanksgiving Day. Appears we`ll see additional rain Wednesday night associated with occluded front and associated frontal rain band. Behind this front, lapse rates steepen with gusty westerly winds and developing low-level CAA for Thanksgiving Day. Moisture advection from the Great Lakes will bring periods of snow showers, likely mixed with rain showers in the lower elevations of the North Country. May see some accumulation snow across srn St. Lawrence County into the northern Adirondacks...and across the Green Mtns...for Thursday and Friday associated with lake effect snow showers and favorable orographic ascent. Have increased sfc winds for Thanksgiving Day given better model consensus for strong W-WSW gradient flow. Wind speeds of 15-25 mph and some gusts 30-35 mph are possible for Thanksgiving Day. Not expecting any major travel impacts with temperatures generally in the 30s to lower 40s for the bulk of the daylight hrs on Thanksgiving, but we continue to ask that you please follow the latest forecasts, especially if you have any travel plans during this period. Some localized travel impacts are likely in the higher elevations and across srn St. Lawrence County due to lake enhanced snow shower activity. Those conditions will persist into Thursday night/Friday, with gradually cooling temperatures that will be somewhat more conducive for snow accumulation late in the forecast period. Should see high pressure bringing snow showers to an end Friday night into Saturday. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... Through 12Z Monday...Mainly VFR early this morning with increasing mid-high level cloud cover from west to east and light wind conditions. Approaching shortwave trough from the Great Lakes region will bring periods of light snow, starting at SLK/MSS by 13-14Z, and across the Vermont TAF sites after 14Z. Only light snow accumulation is expected...generally a coating to 0.5", but vsby may occasionally drop to 1-2SM range this afternoon into the early evening hours. Expect a mix or transition to rain at KMSS this aftn with some warmer air reaching the St. Lawrence Valley on southwesterly flow. Temperatures will also get above freezing at BTV by 16-17Z, which will limit accumulation on paved surfaces. Winds overall generally light, mainly S to SW at 5-9kt during the late morning through afternoon period and then becoming light nwly after sunset with trough passage. Orographic snow showers will continue during Sunday night, with 3-5SM -SHSN possible at KEFK/KMPV and KSLK. Outlook... Monday: Mainly VFR, with local IFR possible. NO SIG WX. Monday Night: VFR. NO SIG WX. Tuesday: VFR. Chance RA. Tuesday Night: MVFR/IFR conditions possible. Likely RA, Chance SHRA. Wednesday: Mainly MVFR, with areas IFR possible. Chance SHRA. Wednesday Night: Mainly MVFR, with local IFR possible. Likely SHRA, Chance SHSN. Thanksgiving Day: Mainly VFR, with areas MVFR possible. Chance SHRA, Chance SHSN. && .EQUIPMENT... NOAA Weather Radio station WXM-44, transmitting from Mt. Ascutney, Vermont, on frequency 162.475 MHz is non-operational at this time. NWS technicians have diagnosed the problem, but repairs will likely not be able to occur for quite some time due to circumstances beyond our control. Therefore, the time of return to service is currently unknown. The following NOAA Weather Radio transmitters may be able to provide service during this outage: WWG 50 from Burke Mtn, VT at 162.425 MHz and WNG 546 from Hanover, NH at 162.525 MHz. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Kutikoff NEAR TERM...Kutikoff/Storm SHORT TERM...Kutikoff LONG TERM...Banacos AVIATION...Banacos EQUIPMENT...Team BTV