


Area Forecast Discussion
Issued by NWS Burlington, VT
Issued by NWS Burlington, VT
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831 FXUS61 KBTV 020223 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 1023 PM EDT Tue Apr 1 2025 .SYNOPSIS... Breezes will continue this evening before becoming lighter overnight through the day on Wednesday. The next frontal system will move through the region Wednesday night and Thursday bringing mixed precipitation including snow, sleet, rain, and freezing rain, and gusty winds. Dry conditions return Thursday night through Friday with mild temperatures before another round of precipitation and a cooling trend occur over the weekend into next week. && .NEAR TERM /THROUGH THURSDAY/... As of 1021 PM EDT Tuesday...Main focus of this update was to decrease hourly dew points as significantly drier air flows in from the northwest. Skies are also trending a bit more clear than previously forecast, though high clouds will soon overspread the area tonight. Have increased winds slightly in the Champlain Valley as we continue to see sustained winds 10-15 knots. Otherwise, forecast is on track. Previous discussion: * A Winter Weather Advisory has been issued for northeastern Vermont from 8 PM Wednesday through 11 AM Thursday. A storm system will bring breezy to gusty winds and mixed precipitation with accumulating snow, sleet, and freezing rain. Isolated power outages are possible and the Thursday morning commute may become hazardous. Breezy winds this afternoon with subside late this evening and overnight with clear skies and cold temperatures. Lows overnight will dip into the teens in the Adirondacks and northeastern Vermont with upper tees and low 20s for broader valleys. RH will drop Wednesday afternoon into the 25-35% range while winds transition from a northerly flow regime to southerly late Wednesday afternoon. Precipitation chances increase Wednesday night as a frontal system tracks through the Northeast. Character of this system will be somewhat similar to the last one with primary concerns for mixed precipitation and increasing wind gusts. Fortunately, the system`s speed will push the transition from snow to mixed precipitation to rain for most locations. The exception will be northeastern Vermont where cold air will be more difficult to scour out overnight. Precipitation: Precip will start as snow late Wednesday before thermal profiles warm aloft supporting a transition to sleet for many locations, and freezing rain for portions of the Adirondacks and eastern Vermont. Best chances for accumulations in excess of 0.01" of ice will be northeastern Vermont with accumulating snow up to a couple/three inches. The combination of precipitation types and potential for up to 0.25" of ice accumulation warranted the issuance of a Winter Weather Advisory in Orange, Washington, Lamoille, Orleans, Caledonia And Essex counties of Vermont. Elsewhere, dry surface conditions will promote more wet-bulbing keeping snow longer with a faster transition to all rain. Winds will result in shadowing along northern slopes, especially in the Adirondacks. Winds: A 50-75kt 850mb low level jet is progged to move across the region with this storm system. These are anomalously strong speeds and will result in potential for gusty conditions for downslope and channeled locations. Surface direction will be out of the south- southeast with north-northwest aspects favored for downslope and the northern Champlain Valley favored for channeled winds. However, this jet will be coincident with precipitation resulting in drag and a lowering of max potential speeds. Gusts will generally be 25-40 mph Wednesday night, but could have "bursts" to 50 mph at times when ducting winds break trough the low level stable layer. Gusts continue into Thursday and increase for some locations; please see the discussion in the Short Term section below. && .SHORT TERM /THURSDAY NIGHT/... As of 401 PM EDT Tuesday...Thursday remains on track to be a warm and breezy day for most of our region, as yet another strong low pressure system passes well to our northwest. In Vermont, winds largely will be significantly strong, aside from the early morning strong channeled winds near Lake Champlain. As temperatures rise and become substantially warmer than the lake air, the gusts will relax, although portions of the eastern Champlain Valley could still see some 40 MPH gusts through late morning. Now within the range of having some higher resolution model guidance, the main change with this forecast was to further enhance winds/wind gusts, particularly during the afternoon into early Thursday night as winds turn more southwesterly, and eventually westerly, with good mixing potential as temperatures cool aloft amidst diurnal heating. The strongest gusts are favored in northern New York where the topography is more favorable for enhanced wind gusts during the mid to late afternoon as a dry slot in the system moves across the area. Wind Advisories will likely be needed with much of the area likely to see numerous wind gusts in the 40 to 50 MPH range, and then expect that a more localized 50 to 55 MPH zone will be in northern Franklin and especially western Clinton and Essex Counties in New York. A potent jet, unseasonably strong in the 60 to 70 knot range at 850 millibars, will be present during this period. By evening, stronger pressure rises will be occurring and low level westerly flow will develop and weaken slightly. Secondarily, rain will taper off in the morning and then maybe some isolated, light showers will develop along a pre-frontal trough. Relatively high chances of these isolated showers will be in eastern/southern Vermont, but generally the environment looks very dry with too little heat to overcome the lack of moisture to drive any convection. Temperatures will be somewhat like Monday, although there eastern Vermont is more likely to break out into warm air during the afternoon. Highs in most places will be in the 60s, and dew points a bit elevated in the mid 40s to low 50s. With post- frontal air Thursday night coming in from the west, cold air advection will be modest with temperatures remaining above freezing areawide. As such, winds will quickly taper off overnight, as well. && .LONG TERM /FRIDAY THROUGH MONDAY/... As of 401 PM EDT Tuesday...Friday clearly is the pick of the week/long term forecast for outdoor activities. Modest northwest winds will accompany seasonably mild air and plenty of sun. High temperatures will be in the upper 40s to upper 50s areawide. More impactful weather is possible this weekend, although signals for more freezing rain/wintry weather are relatively low at this time. Per the latest ensemble cluster analysis, a multi-model blend with a more amplified trough/ridge scenario across the country leads to greater risk of meaningful ice accumulation on Saturday at the onset of precipitation in the eastern Adirondacks and central/eastern Vermont. Given the inherent uncertainty in this scenario, for now the forecast is all rain or snow, and mainly rain as the storm track is yet again forced to our west with a strong ridge centered over the western Atlantic in a stagnant pattern. Precipitation may occur in a few waves beginning Saturday morning through Sunday night until a cold front sweeps through. There is decent model agreement on greatest rainfall occurring in southern areas. Most likely timeframe of heavier rain currently looks to be in the Saturday night through Sunday morning period, with some suggestions of more than 1" of precipitation in 24 hours in portions of Essex County, New York. Following this system, there has been good agreement in long range models of a colder than normal period for early next week, which will promote chances of higher elevation snow showers on both Monday and Tuesday. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... Through 00Z Thursday...Conditions will remain VFR through the forecast period. Main aviation concern will be gusts 20 to 30 kts resulting in some minor turbulence through ridge level. After 00-06Z, winds decrease with more ideal conditions for aviators. The next storm system will move in after 21z, but strong turbulence/LLWS associated with a potent low level 850mb jet and potential for mixed/clear icing will be hazards Wednesday night into Thursday. Outlook... Wednesday Night: Mainly MVFR and IFR, with areas VFR possible. Strong winds with gusts to 40 kt. Definite RA, Definite SN, Definite PL, Chance FZRA. Thursday: Mainly MVFR, with local IFR possible. Strong winds with gusts to 40 kt. Likely RA, Chance SHRA. Thursday Night: VFR. Windy with gusts to 30 kt. NO SIG WX. Friday: VFR. NO SIG WX. Friday Night: VFR. NO SIG WX. Saturday: VFR/MVFR conditions possible. Likely RA. Saturday Night: Mainly MVFR, with areas IFR possible. Definite RA. Sunday: Mainly IFR, with areas MVFR possible. Chance RA. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...Winter Weather Advisory from 8 PM Wednesday to 11 AM EDT Thursday for VTZ003-004-006>008-010. NY...None. && $$ SYNOPSIS...Boyd NEAR TERM...Boyd/Storm SHORT TERM...Kutikoff LONG TERM...Kutikoff AVIATION...Neiles