418
FXUS61 KBTV 061137
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
737 AM EDT Wed May 6 2026
.WHAT HAS CHANGED...
As of 245 AM EDT Wednesday...
Refined timing of precipitation for today. Steady rainfall is
expected to continue this morning, gradually coming to an end
from west to east this afternoon. Total precipitation amounts
are on track.
&&
.KEY MESSAGES...
As of 245 AM EDT Wednesday...
1. Expect a wet day today with several daily record
precipitation amounts forecast to be broken. Outside of some
ponding in poor drainage areas, no flooding is anticipated.
2. Cooler temperatures are expected the second half of the week
with some patchy frost possible.
3. An unsettled pattern anticipated for days 4 thru 7 but the
probability of widespread hazardous or significant weather is low.
&&
.DISCUSSION...
As of 245 AM EDT Wednesday...
KEY MESSAGE 1: Today will be a cooler and wet day with steady
rain anticipated to last much of the morning into the early
afternoon. A frontal boundary (oriented SW to NE around the
Saint Lawrence Valley as of 2 AM) will very slowly shift
eastward through the day and into this evening. A wave of low
pressure developing along the boundary (located over the Ohio
River Valley as of early this morning) will ride northeastward
along the boundary, serving as an additional focal point for
convergence over our CWA today. The duration of today`s rainfall
will be prolonged by nearly boundary- parallel upper-level
flow, which will limit the eastward progression of the frontal
boundary to a very slow pace. Rain will eventually come to an
end from west to east during the early afternoon hours in
northern NY, and late afternoon to early evening hours in VT.
Rainfall rates today will intensify at times to 0.1-0.2
inch/hour during the daylight hours over central portions of our
CWA. This is due to deep lift (enhanced surface convergence
with a coupled jet structure aloft/strong upper-level
divergence) occurring within a moist airmass (precipitable
water values over 1.0 inch). Storm total rainfall amounts today
will range from a 0.25-0.75 inch in the Saint Lawrence Valley
and southeastern Vermont, to 0.75-1.25 inch over the northern
Adirondacks, Champlain Valley, and northern Vermont. These
precipitation amounts would break several daily precipitation
records, including at Burlington, Plattsburgh, and Saranac Lake
(see Climate section for more). Rivers will rise in response to
these rainfall amounts, but forecasts from the Northeast River
Forecast Center keep all of our area rivers well within banks,
and no river flooding is expected.
With the front forecast to bisect our forecast area today, afternoon
daily high temperatures will range from the 40s for northern NY and
northwestern VT to the 60s in southeastern Vermont. With respect to
24 hour daily high temperatures, these have already been reached at
midnight for much of our forecast area, and temps will fall for the
remainder of the day for all except southeastern Vermont.
KEY MESSAGE 2: After the passage of today`s cold front, temperatures
Thursday through Saturday will be cooler than seasonal norms for
early May. Highs will be in the 50s to around 60 for most of the
area, and lows will be in the 30s to around 40. Broad cyclonic flow
aloft will keep skies at least partly cloudy overnight with some 5-
15 knot winds just off the surface. This will prevent any strong
radiational cooling nights with widespread frost development,
but some patchy frost is possible. The best chance for frost
will be Friday morning, though frost is not forecast in any
areas that have started their "growing season". As per our
frost- freeze program, the only area that has started the
growing season at this point is the Champlain Valley. Therefore,
no headlines are anticipated at this point. However, anyone
with sensitive vegetation should monitor the low temperatures
forecast over the next few days.
KEY MESSAGE 3: The synoptic scale pattern acrs the conus wl feature
mid/upper lvl ridge acrs the west and deep trof from the Great Lakes
into the northeast conus. This general west/northwest flow aloft
with embedded s/w`s and lobes of enhanced mid lvl moisture wl keep
fa unsettled for upcoming weekend into next week. Latest 00z trends
have tracked Saturdays system slightly further south with better
dynamics/moisture, but mid/upper lvl trof passage and lingering
moisture wl produce some scattered showers. Probably not a washout,
but not completely dry either.
The highest probability and greatest confidence for another
widespread rainfall is late Sunday into Monday, as global guidance
has come into better agreement. A developing full latitude trof with
phasing of northern and southern stream energy wl help in the
development of sfc low pres over the Ohio Valley on Sunday. This low
pres is progged to deepen as it tracks toward the ne conus late
Sunday into Monday. Strong southerly flow and deep moisture
advection, combined with favorable ulvl jet structure wl continue to
place high likely pops into the fcst for late Sunday into Monday.
Upslope flow and caa wl cont pops acrs the mtns on Monday into
Tuesday, before sfc high pres finally builds back into our cwa by
Weds. The warmest day looks to be Sunday, as waa ahead of sfc low
pres advects progged 925mb temps btwn 10-14C, supporting highs well
into the 60s to lower 70s. Much cooler air develops on the backside
of low pres for early next week with highs only in the upper 40s to
upper 50s expected, with lows in the mid 30s to mid 40s. Winds and
clouds wl limit temps from falling too much.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
Through 12Z Thursday...A very challenging taf package with
regards to CIGS/VIS in the next 6 to 12 hours. Crnt radar
imagery shows light to moderate rain expanding across our taf
sites with a wide range of flight categories from LIFR at RUT to
IFR at MPV, MVFR at SLK/EFK/MSS and VFR at BTV/PBG. Sounding
profiles and upstream obs indicate most taf sites trend quickly
to MVFR cigs/vis by 14z with intervals of IFR possible. As winds
continue from the north/northwest, except northeast at SLK/PBG,
expect intervals of IFR cigs to develop, especially
BTV/RUT/PBG/EFK and slightly less potential at SLK/MSS due to
wind direction. However, as surface low pres passes to our east,
northwest flow develops and SLK should drop to IFR cigs by early
this aftn. Have utilized tempo groups to walk flight categories
toward IFR conditions today, while slowly improving conditions
are anticipated by late today into tonight.
Outlook...
Thursday: VFR. NO SIG WX.
Thursday Night: VFR. NO SIG WX.
Friday: VFR. Slight chance SHRA.
Friday Night: VFR. Chance SHRA.
Saturday: VFR. Chance SHRA.
Saturday Night: Mainly VFR, with local IFR possible. Chance SHRA.
Sunday: Mainly VFR, with local MVFR possible. Chance SHRA.
&&
.CLIMATE...
Daily Precip Records
Date KBTV KMPV K1V4 KMSS KPBG KSLK
05-06 0.85|1894 1.55|1989 0.39|2010 0.84|1991 0.42|1991 0.75|2017
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Duell
DISCUSSION...Duell/Taber
AVIATION...Taber
CLIMATE...
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