Area Forecast Discussion
Issued by NWS Burlington, VT
Issued by NWS Burlington, VT
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048 FXUS61 KBTV 061324 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 924 AM EDT Sun Oct 6 2024 .SYNOPSIS... One more mild and dry day will give way to widespread rain tonight ahead of a cold front. Additional more scattered showers will be possible Monday ahead of a secondary front which will usher in seasonably chilly air and occasional chances of rain and high elevation snow showers midweek. The colder air will begin to moderate moving into next weekend. && .NEAR TERM /THROUGH MONDAY/... As of 923 AM EDT Sunday...Morning satellite imagery shows fog well entrenched within the Winooski River Valley and near Newport. Given the latest trends in satellite imagery, it`s plausible this fog could linger through almost noon before being replaced by mostly sunny skies. Elsewhere, plentiful sunshine is already being seen with temperatures warming quickly after some of the coldest temperatures seen since last April. Rainfall looks to hold off until after sunset so it`ll be another great day to enjoy the North Country. Previous Discussion...Widespread fog has developed in the climatologically favored river valleys early this morning, with otherwise crisp, seasonably cool and dry weather to start the day. Temperatures should rise quickly into the 60s as southerly winds develop, with another warm afternoon ahead. Changeable weather will develop late in the day as a well defined frontal system barrels eastward. This dynamic frontal system will be steered northeastward through southern Canada through the next couple of days, bringing a well-defined line of showers through our region followed by a dry slot and a secondary cold front. With this storm track, we`ll have ample warm air advection, supporting mainly elevated convection. Greatest chances of a rumble or two of thunder continues to be as you go west, and have added in slight chance of thunder in much of southern St. Lawrence County this evening where low level moisture and temperatures look sufficient to get some MUCAPEs near 500 J/kg. As you go eastward there is increasing spread in CAMs depicting stronger convection capable of thunderstorms, as a sharp decreasing trend in instability is evident. Rainfall amounts will be limited by duration of rainfall in western areas and intensity of rainfall in eastern areas. Upstream satellite imagery in northern Michigan and model depiction of water vapor, there is a pretty narrow axis of deep moisture and it is tied to some strong low level winds. Expect this low level jet to reintensify this evening into the early morning hours right over our region. Wind gusts of 30 to 35 MPH will be possible near Lake Champlain during this period as well as locally in portions of the northern Adirondacks and northern Greens during this period. A lighter, steady rainfall will tend to redevelop behind the initial line in much of Vermont as this jet slides through overnight. It will be followed by a pronounced dry slot, which will be enhanced by modest, downsloping westerly flow that will develop tomorrow morning. Isolated to scattered showers are expected to be triggered by weak instability and low level convergence ahead of a secondary boundary that crosses our region from west to east during the day. This front does not look as sharp as the one that comes through tonight, thus more uncertainty as to where and when it will rain. As such, PoPs are largely kept in 25% to 50% range and most of the day will probably be dry. Associated with deep mixing, temperatures will trend only a bit cooler than recent days with highs likely to top out in the upper 50s to mid 60s. && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY/... As of 318 AM EDT Sunday...1000-500mb thicknesses are gonna be on the decline as an upper low swivels to our north. Such will bring cooler conditions with mid 30s to mid 40s. Based on the positioning, we may experience more westerly flow as opposed to northwest flow, and that appears to allow just a little moisture off Lake Ontario to move across the region. With some diurnal destabilization, we could be looking at isolated pop up showers while we sit beneath the core of the upper low, but did elevate precipitation to 25-35 percent across parts of the Dacks and far northern Vermont during the day. Conditions will be cool, with highs in the 50s and some lingering lower 60s near Springfield. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... As of 318 AM EDT Sunday...Forecast models have come into better alignment on the timing of the vort expected to round the upper low. It looks like it will pivot southeast Wednesday evening into Thursday. Such is a bit less ideal since this will mean that mid- level cooling will have to fight diurnal heating for bringing down snow levels. The low-levels are going to be quite dry, but there is quite a bit of moisture between 850-700mb that should permit the development of a few mountain snow showers. The dry low-level conditions may allow snow to reach down toward 1500 ft agl, but should prevent any accumulations with activity sublimating/evaporating away and yield mainly flurries. High temperatures for Wednesday and Thursday will be in the 40s to mid 50s. Wednesday morning appears likely to be the coolest night, with a moisture minimum and lightest winds. The Adirondack airport is currently forecast to reach 24 F, and surrounding areas are generally in the 30s. Widespread frost appears pretty likely Wednesday morning. A few lingering showers in favorable northwest flow appears possible Thursday. By Friday into the weekend, the upper low will begin to shift east with a ridge replacing it. This should warm temperatures up and dry us out. So it should be a nice weekend. There`s a potential system out there for the early part of next week, but plenty of spread is out there. Understandable, since it`s bordering day 8 in the forecast. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... Through 12Z Monday...Some lingering dense fog at SLK/EFK/MPV through 13Z to 14Z, but otherwise VFR conditions are expected today through at least 00Z. Then some MVFR conditions will develop associated with steady rain along a frontal boundary at all sites, with a transition to lower ceilings towards 12Z especially at EFK and MPV, and possibly at MSS. A non-zero chance of thunder also exists especially in the 00Z to 03Z period, with any lightning a bit more likely at western terminals. Calm or light drainage wind will trend south-southeasterly, with gusts to around 20 knots by 18Z possible at PBG/BTV and to around 15kts elsewhere. As a strong frontal system enters the region between 00Z and 06Z, wind fields will further increase leading to areas of LLWS. For now, have mention of LLWS at SLK and EFK where a more stout low level inversion looks to support very sharp speed shear, but directional shear is marginal for the period. Outlook... Monday: Mainly VFR, with local MVFR possible. Slight chance SHRA. Monday Night: VFR. Slight chance SHRA. Tuesday: VFR. Slight chance SHRA. Tuesday Night: VFR. Slight chance SHRA. Wednesday: VFR. Chance SHRA. Wednesday Night: Mainly VFR, with areas MVFR possible. Chance SHRA. Thursday: Mainly VFR, with local IFR possible. Slight chance SHRA. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Kutikoff NEAR TERM...Clay/Kutikoff SHORT TERM...Haynes LONG TERM...Haynes AVIATION...Kutikoff