textproduct: Burlington

SYNOPSIS

A trough will help spark light snow and support breezy southwest winds later today through tonight, resulting in accumulations primarily in the western foothills of the Adirondacks and in the mountains across northern New York and Vermont. Seasonable temperatures today will become a bit above normal on Tuesday and Wednesday in advance of a strong cold front. Chances for precipitation, and potentially widespread snowfall, increase Wednesday night into Thursday as much colder air spills into the region.

NEAR TERM /THROUGH TUESDAY/

As of 124 AM EST Monday... *Minor travel impacts today into tonight associated with light snow and some areas of blowing snow are expected today

An active, if not particularly impactful, weather pattern continues. Right on the heels of the gusty winds and snow showers early this morning will be the next system coming across the region from the west this afternoon. Early this morning a mid-level trough tied to a clipper-type of system in northern portions of eastern Canada is producing light snow over the Upper Peninsula of Michigan. As the trough and associated enhanced moisture tracks towards the east-southeast, low level west-southwesterly flow will further increase low level moisture from the eastern Great Lakes. As such, clouds and light snow will blossom this morning over northern New York. The 230-240 degree wind direction is typically favorable for lake- effect snow in our forecast area, although in this case the instability over Lake Ontario is limited with only about a 10 degree Celsius air-lake temperature difference. Relatedly, most modeling shows limited banded structures, and rather a broad area of light to moderate snow develops downwind.

Have continued to show high probabilities of snow, with areas of blowing snow, in much of southeastern St. Lawrence County where combination of upslope flow and vicinity to greater moisture continues to suggest localized higher impacts. A similar scenario, but later in the day and generally with lighter snowfall rates, is expected for the far northern Green Mountains. Outside of a burst of light snow in northern New York during the late morning and the aforementioned snowfall in the western Adirondacks and northern Greens, much of the higher terrain across Vermont and New York should see periods of light snow through much of the afternoon into tonight, with mainly flurries in the valleys east of the Adirondacks. Little weather of interest follows for Tuesday, but have started boosting winds/wind gusts a bit later in the day as southerly flow increases with pressure falls ahead of a stronger frontal system.

SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/

As of 124 AM EST Monday... * Increasing chances for valley rain and higher elevation snow showers

A strong cold front, with surface low initially tracking well to our northwest, will keep precipitation chances pretty low for this period, with our far northern and western areas somewhat more favorable for period of elevationally-dependent rain/snow showers. The orientation of the trough supports only a little bit of water vapor transport from lower latitudes/subtropical air, with most of the enhancement of precipitation north of the Great Lakes through this timeframe ahead of the front. During the day on Wednesday some showers will tend to eke farther east as the front slowly moves eastward. Air aloft will be sufficiently cold for snow, so it will be a boundary layer issue for precipitation type. As of 120 AM EST Monday. In fact, valley high temperatures are expected to reach as high as the lower 40s.

LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/

As of 120 AM EST Monday...The latter half of the week continues to be dominated by a complex and interesting set up as we'll be under the influence of a deep upper trough. A tight temperature gradient will exist on the eastern edge of this trough Wednesday night and Thursday, between high pressure to our west and a surface low developing somewhere of the Northeast coast. Exactly where this gradient sets up is still uncertain, as evidenced in the significant spread in the 25th and 75th percentiles for Thursday's high temperatures via the NBM; much of the region has 10-20F spread, compared to just 2-4F on the preceding day. Regardless, with the frontal boundary wavering somewhere in our vicinity, anticipate increased shower chances for Wednesday night and Thursday, with the model consensus showing the front setting up just to our south by Thursday night/Friday. This solution would lead to sharply colder temperatures Thursday, keeping precipitation in the form of snow and highs only in the teens and 20s. Trends will need to be watched though, as the front could remain further north than currently anticipated, particularly if a wave of low pressure develops along it.

Things become even more uncertain for Thursday night/Friday and into the weekend as an upper low will swing across the Northeast/Appalachians, and eventually out over the Atlantic. Where its surface low will track remains uncertain, with both the GEFS and ECMWF ensemble members placing the low anywhere from NJ/PA to Downeast Maine to well south of Nova Scotia. Obviously, this has implications for how much, if any, precipitation we would get for week's end. It should be noted that the GFS continues to show a very dry airmass in place behind the aforementioned front, with PWATs 0.25 inch at best Thursday night/Friday. At this point, have stayed fairly close to the NBM solution for Thursday night through Sunday, with slight chance to low chance PoPs and temperatures warming back up close to normal for the weekend.

AVIATION /11Z MONDAY THROUGH FRIDAY/

Through 12z Tuesday...Snow has mostly ended across the region this morning, with only KEFK still reporting IFR conditions in snow. This too should end in the first few hours of the TAF period, with a mix of MVFR/VFR to prevail at all terminals through the remainder of the morning hours. However, snow returns this afternoon and evening, especially at KMSS/KSLK/KEFK. Visibility 1-3SM in any snow, but ceilings to remain 1500-2500 ft. All other terminals should see clouds thicken and lower to around 3000 ft, give or take 500 ft or so this afternoon and remain so through the rest of the TAF period. While a snow shower or two cannot be totally ruled out at the other terminals, particularly KMPV and KBTV, coverage/certainty is not high enough to warrant mention in the TAFs at this time. Gusty W/NW winds will continue at 20-30 kt through this morning, then gradually subsiding this afternoon. The exception will be KSLK/KMSS which will hold onto stronger gusts through the TAF period. Periods of LLWS are expected at most terminals, with KPBG/KBTV the only exceptions.

Outlook...

Tuesday: Mainly VFR, with local MVFR possible. NO SIG WX. Tuesday Night: Mainly VFR, with local MVFR possible. Chance SHRA, Chance SHSN. Wednesday: Mainly MVFR, with local IFR possible. Chance SHRA, Chance SHSN. Wednesday Night: Mainly MVFR, with areas IFR possible. Likely SHSN. Thursday: Mainly VFR, with areas MVFR possible. Chance SHSN. Thursday Night: VFR. Chance SHSN. Friday: VFR. Slight chance SN, Slight 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.

The Colchester Reef meteorological station is out of service. This site is not serviced by the NWS and there isn't an estimated return to service at present. Use extra caution when navigating the broad waters of Lake Champlain. Please contact us if you observe winds significantly deviating from the recreational forecast.

BTV WATCHES/WARNINGS/ADVISORIES

VT...None. NY...None.