####018008264#### FXUS61 KBTV 090638 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 138 AM EST Tue Dec 9 2025 .SYNOPSIS... After a cold start to the morning, temperatures will quickly rise today as southerly flow develops. Widespread light snowfall will move through tomorrow into tomorrow night, with accumulations generally expected to be in the two to five inch range. The colder and active pattern will continue into next week with a few additional chances for snow, though no big snowstorms are expected. && .NEAR TERM /THROUGH TONIGHT/... As of 137 AM EST Tuesday...Mostly ideal radiational conditions have developed tonight, causing temperatures to drop quickly. Everywhere outside the areas immediately along Lake Champlain have fallen below 0, with many areas outside the broad valleys around and below -10. Temperatures will drop a few more degrees in most places before the night is over. While southerly flow will begin to develop late in the night, it should not have a significant effect on impeding the radiational cooling. While this cold is uncommon for the time of year, it is not unprecedented. Plattsburgh looks to have broken two record lows already. It was -11 right at 1159/1200, breaking the -7 record on 12/08 and the -10 record on 12/09. The cold temperatures and relatively light winds have allowed a lake cloud to develop on the mostly unfrozen Lake Champlain. It has formed over the southern waters and it will gradually expand northward as the night goes on. It may move into areas adjacent to the lake in the early morning. Increased southerly flow and associated mixing/drying, along with warming temperatures, should cause it to dissipate during the day. An area of warm air advection aloft will move through this evening and cause a period of light snow. Very dry low levels will likely cause a lot of it to evaporate before it reaches the ground, but there should still be some very light snow. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... As of 137 AM EST Tuesday...A quick moving storm system moves through Wednesday and Wednesday night, tracking up the St. Lawrence Valley. Warm air advection should cause a quick period of moderate to heavy snow on the front end. Here, snowfall rates could briefly reach around an inch per hour. The snow will become lighter for the rest of the day and into the night, and a dry slot moves in for the evening. Strong southwesterly winds will cause downsloping and mostly end the precipitation in the Champlain and Connecticut valleys in the afternoon. Gusts in the 25 to 35 mph range are possible in the Champlain Valley as enough of a southerly component and an inversion below ridgetops should allow for efficient channeling. Temperatures will rise slightly above freezing in the broad valleys, but steep lapse rates should mostly keep the precipitation snow. As the center of the low passes to the east, northwest flow develops and it should cause a brief period of upslope snow Wednesday night. Overall, totals in the two to five inch range are generally expected. The lake effect band should stay to the south of our northern New York zones, though the moisture will still enhance totals in the central and southern Greens. Drier conditions should prevail during the day Thursday, but moisture looks to back down from the north and reinvigorate the upslope snow in the evening. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... As of 137 AM EST Tuesday...Primary highlights for the long term include upslope snow showers on Thurs night into Friday, another light snow event on the weekend, followed by another very cold airmass late Sunday into early next week. First item wl be a classic upslope fluff event on Thurs night into Friday, as progged 850mb temps fall btwn -12F and -20F with lingering 925mb to 500mb rh >70%. Latest GFS/ECMWF show the closed 700/500mb circulation becoming vertically stacked just north of the International Border, which should promote favorable 925mb to 850mb winds of 25 to 40 knots, resulting in additional upslope accumulating snowfall thru Thurs night. Have bumped pops into the high likely range for Thurs night with additional accumulations of 2 to 4 inches of fluff, but localized 4 to 6 inches possible from Mansfield to Jay Peak. We will continue to monitor depth of moisture to fine tune snowfall amounts, but moderately strong caa should help squeeze out remaining moisture in the mtns. Next fast moving clipper like system associated with positively tilted mid/upper lvl trof arrives late Sat into Sun. Did note the 00z ECMWF is a bit more aggressive with sharpening trof and develops a slightly stronger area of sfc low pres along the mid Atlantic into southern New England. The GFS/UKMET and CMC show more of a clipper like system with a period of light snow late Sat into Sunday, followed by another very cold airmass late Sunday into early next week. This airmass looks to be associated with bitterly cold wind chill values as progged 850mb temps drop btwn -22F and -25F with gusty northwest winds. Cold headlines are likely needed for Sunday night into Monday. This wl be an advection type of cold on Sunday night, followed by radiational cooling on Monday night into Tues with building sfc high pres. Given latest trends additional lowering of temps is likely on Sunday through Tuesday of next week, where highs may struggle to reach 10F in many spots on Monday, with values well below zero again on both Sunday and Monday nights. Cold air wl help to squeeze out a few upslope snow showers on Sunday into Sunday night, before column becomes too dry. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... Through 06Z Wednesday...TAF challenge in the next 6 hours will be if some low stratus clouds could develop at BTV/MPV or EFK and produce localized intervals of IFR cigs. Crntly temp dwpts spread is large, but GOES 19 nighttime microphysics imagery shows some lake enhanced clouds building over the central/southern Lake Champlain area at this time. Given this development have tempo'd btwn 09-12z 2SM BR BKN004, to cover this probability given satl trends. Otherwise, VFR conditions prevail with developing south/southwest 10 to 15 knots gusts 15 to 25 knots likely after 15z today. A band of light snow with mvfr vis and vfr cigs develops after 00z across our northern NY taf sites and spreads into VT toward 03z Weds. Outlook... Wednesday: MVFR/IFR conditions possible. Definite SN. Wednesday Night: Mainly MVFR, with local IFR possible. Chance SHSN. Thursday: VFR. Chance SHSN. Thursday Night: VFR. Slight chance SN. Friday: Mainly VFR, with local MVFR possible. NO SIG WX. Friday Night: Mainly VFR, with areas MVFR possible. Slight chance SN. Saturday: Mainly VFR, with areas MVFR possible. Chance SN. && .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. Equipment malfunctions at the Colchester Reef meteorological station will likely leave it inoperable for an extended period of time. This site is not serviced by the NWS. Technicians do not currently have an estimated return to service for this station. Use extra caution when navigating the broad waters of Lake Champlain, and please contact us if you observe winds significantly deviating from the forecast. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Myskowski NEAR TERM...Myskowski SHORT TERM...Myskowski LONG TERM...Taber AVIATION...Taber EQUIPMENT...Team BTV ####018012359#### FXUS61 KBUF 090638 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 138 AM EST Tue Dec 9 2025 .SYNOPSIS... Two waves of low pressure will pass by our region, with the first to arrive this afternoon in the form of widespread, but light, synoptic snow. Southwest winds behind this wave will deposit several inches of lake effect snow downwind of Lake Erie on a southwest flow this evening and into tonight, with a few inches of snow also falling through the Saint Lawrence Valley off Lake Ontario tonight. A more potent storm system will arrive later tonight, with snow and gusty winds, with this snow mixing with rain late tonight and Wednesday across lower terrain, while hills tops may remain as just snow through the event, with this snow heavy at times. && .NEAR TERM /THROUGH TODAY/... Surface high pressure over the eastern Great Lakes will ensure generally dry and quiet albeit frigid weather remains in place through this morning. Temperatures remain some 15 to 20 degrees below normal tonight. The surface ridge axis will slide south and east of the Great Lakes and past the spine of the Appalachians overnight. Low level flow should begin to turn southerly and the overhead airmass modify a few degrees as a result. Despite this, it will still be cold enough with winds remaining light enough such that with the snowpack across the region, temps should easily slide back into the single digits early this morning, with many spots across the interior falling below zero. Otherwise, a thin plume of low level moisture will continue off the east end of Lake Ontario overnight. Combined with diurnal land-breeze convergence and some enhancement from the lake, this will continue to produce a weak band of LE snow off the eastern end of the lake. Band will remain closer to the lakeshores from roughly Oswego to Watertown, with these areas possibly picking up a dusting to perhaps a localized inch or so. Our stretch of quieter weather will be cut short Tuesday as a weakening clipper system tracks through the Upper Great Lakes, becoming further disorganized and diffuse as it moves east. The mid- level shortwave driving this system will make its way through the forecast area Tuesday afternoon into early Tuesday evening, with a warm frontal segment moving through from west to east. This will cause light snow to once again overspread much of the region, with lake enhancement developing northeast of the lakes (mainly Lake Erie) late in the day. A stiff southerly flow and subsequent downslope drying/upslope enhancement will should yield minimal accumulations by the evening (generally 0.5" or less) in the Genesee Valley and Finger Lakes, as well as on the leeward side of the Tug. The higher amounts are expected across the Niagara Frontier including the Buffalo Metro and east of Lake Ontario across the southern slopes of the Tug Hill Plateau itself. Snowfall in these areas should still be minor with 1-3" by the late afternoon, though more will be on the way as lake effect bridges the short gap until the next synoptic system arrives...More on that in the short term below. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... A complex forecast scenario will unfold Tuesday night through Wednesday night as a strong clipper low passes by just to our north. There continues to be enough spread in model guidance to bring considerable uncertainty to the forecast in terms of snowfall amounts, precipitation type, and wind potential. Tuesday evening, a brief window of lake effect snow northeast of Lake Erie and Lake Ontario ahead of the clipper system may bring a few inches of snow to the Niagara Frontier (including the Buffalo Metro area) and northern Jefferson County. Ongoing warm advection and lowering inversion heights ahead of the clipper will then shut down the lake response overnight. The surface low will likely pass just north of the area across southern Ontario Wednesday. The GFS remains on the southern edge of the guidance envelope, taking a weaker low directly over Lake Erie and Lake Ontario. If this were to verify, there would be much less wind, and precip type would stay snow for a greater share of the event. This low is not favored climatologically, and will thus favor the farther north solutions seen in other guidance. A period of snow will break out late Tuesday night through Wednesday morning in the warm advection and isentropic upglide ahead of the system. Assuming the farther north track verifies, lower elevations of Western and Central NY will then mix with, or change to rain for a time Wednesday, while the high terrain of the Southern Tier has a better chance of remaining all snow, and also the higher terrain east of Lake Ontario. The lower elevation rain would then change back to snow Wednesday evening as cold advection ramps up following the passage of the clipper cold front, with wrap around upslope snow and the start of lake effect adding some additional accumulations Wednesday night. As far as accumulations go, the greatest snow amounts will be found across the higher terrain of the Tug Hill Plateau and western foothills of the Adirondacks where upslope will enhance QPF, and precipitation is most likely to remain all snow. This area may see totals of 8-12+" from early Wednesday morning through Thursday morning. These higher amounts would be limited to the high terrain, with the surrounding lower elevations of the eastern Lake Ontario region seeing 3-6" accumulations. Across Western NY, total accumulations from late Tuesday afternoon through Thursday morning may reach the 3-6" range across the Niagara Frontier, and 4-9" across the higher terrain of the western Southern Tier. It is important to note that this will fall in 3 different batches, lake effect Tuesday evening, then warm advection snow late Tuesday night/early Wednesday morning, then wrap around snow and lake enhancement Wednesday night. Each of these phases will produce a few inches each. There will be melting during the day Wednesday when temperatures rise well above freezing, especially across lower elevations. It will turn windy as this system moves through the area, but uncertainty with low track, intensity, and associated wind fields makes this a highly uncertain wind forecast. If the farthest north and strongest solutions of the NAM/HRRR verify, we can expect high end Wind Advisory or low end warning criteria gusts (55+mph) northeast of Lake Erie Wednesday, while the farther south and weaker GFS solution would keep winds well below wind advisory criteria. Most model solutions are weaker than the worst case NAM/HRRR, so for now we kept forecast wind gusts near the low end of advisory range northeast of Lake Erie but expect adjustments as the event nears and forecast certainty increases. Thursday through Thursday night cold air will pour back into the eastern Great Lakes, supporting accumulating lake snows southeast of the lakes. There is typical uncertainty with wind direction and snow amounts at this time range, but in general expect the potential for moderate snow accumulations across the western Southern Tier off Lake Erie, and near or just east of Rochester to Oswego County off Lake Ontario. && .LONG TERM /FRIDAY THROUGH MONDAY/... An active and cold pattern will continue Friday through early next week as a deep longwave trough remains over eastern North America. This trough will continue to support below average temperatures and almost daily chances of snow from a combination of clipper systems and lake effect. Model guidance continues to show considerable run to run differences with the synoptic setup through the weekend, which results in uncertainty with respect to lake effect band placement and intensity. In general, the very progressive pattern with frequent clipper shortwaves will likely prevent wind direction and band placement staying the same for any length of time. This will limit the potential for a large lake effect event, but also spread the wealth of accumulating snow to a multitude of different wind directions and locations over time. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... High pressure sliding east of the area will keep mainly VFR flight conditions intact through midday/early Tuesday afternoon. Exception will be remainder of tonight into the first couple of hours Tuesday morning east of Lake Ontario as a weak band of localized lake effect snow off the southeast end of Lake Ontario with limited inland extent will continue to weaken and move north across the Lake Ontario region. VSBYs around 3SM in -SHSN and marginal MVFR CIGS have been observed at KFZY. If this band holds together, a brief period of marginal MVFR/low VFR CIGS will be possible in and around KART from around 10Z-13Z, however any snow shower activity should be very light. Flight conditions will then rapidly deteriorate from early/mid afternoon Tuesday through the end of the TAF period as a warm front extending south from a weak Clipper system approaches, then moves across the area. Expect MVFR CIGS into western NY by mid afternoon, spreading east to the eastern Lake Ontario region by around early evening. A brief period of light snow will also be possible along and ahead of the boundary. This may bring a brief period (1-3 hours) of MVFR/IFR VSBY with timing mirroring the aforementioned onset of MVFR CIGS. A period of localized lake effect snow is then expected to develop in the wake of the warm frontal passage with intermittent MVFR/IFR VSBYs northeast of Lake Erie possibly impacting KBUF and/or KIAG Tuesday evening into the early overnight. Southerly to southwesterly flow will ramp up for Tuesday afternoon and evening as well, with gusts mainly in the 20-25 knot range, however a few gusts to 30 knots is not out of the question. Outlook... Tuesday night...Mainly MVFR/IFR with snow potentially mixing with rain late in the night. Wednesday...VFR/MVFR with rain and snow showers. Breezy, with gusts 20-30kts in many areas. Gusts to 35kts possible at KBUF/KIAG. Thursday...VFR, with MVFR/IFR in scattered to numerous snow showers. Friday and Saturday...MVFR/IFR east of the lakes with snow showers likely. MVFR/VFR outside the main lake effect areas. && .MARINE... High pressure will shift southeast of the lakes overnight with light winds and minimal wave action. The offshore flow will increase and begin to turn southwesterly as a weak system moves east of the Upper Great Lakes Tuesday, which will then be followed by a more potent area of low pressure on Wednesday. Depending upon the track of the surface low, gales are possible Tuesday - Wednesday, with Wednesday the more favorable day, especially over Lake Erie. A Gale Watch was issued for the eastern end of Lake Erie Wednesday. Westerly winds will subside below gale force later Wednesday night into Thursday, though remain elevated through the end of the week. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...Winter Storm Watch from late tonight through Thursday morning for NYZ006>008. Winter Weather Advisory from 1 AM to 10 PM EST Wednesday for NYZ012-019>021-085. MARINE...Small Craft Advisory from 1 PM this afternoon to 4 AM EST Thursday for LEZ020. Small Craft Advisory from 7 AM this morning to 4 AM EST Wednesday for LEZ040-041. Gale Warning from 4 AM to 7 PM EST Wednesday for LEZ040- 041. Small Craft Advisory from 3 PM this afternoon to 10 AM EST Friday for LOZ042. Small Craft Advisory from 9 PM this evening to 6 PM EST Saturday for LOZ043>045. && $$ SYNOPSIS...Thomas NEAR TERM...HSK/PP SHORT TERM...Hitchcock LONG TERM...Hitchcock AVIATION...JM MARINE...PP/Thomas