471
FXUS61 KBTV 250648
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
248 AM EDT Mon May 25 2026
.WHAT HAS CHANGED...
As of 247 AM EDT Monday...
Winds have been increased for Tuesday afternoon, but otherwise no
significant changes were made with this forecast package.
&&
.KEY MESSAGES...
As of 247 AM EDT Monday...
1. Widespread rain this morning will end by this afternoon,
with warmer and drier conditions expected through Tuesday. Tuesday
will also be breezy with gusts of 25 to 40 mph possible along the
international border.
2. Low chances of showers and seasonable temperatures expected
for mid week.
3. Below normal temperatures and some showers are likely late
in the week before conditions trend dry and warmer.
&&
.DISCUSSION...
As of 247 AM EDT Monday...
KEY MESSAGE 1: Much like yesterday, a swath of light to moderate rain
is spreading over the region early this morning. This precipitation
will continue to push eastward through the morning hours as a
surface trough/boundary likewise moves eastward. Moisture converging
along/ahead of the trough has resulted in PWATs exceeding 1.25 inch,
and with warm cloud depths around 10 kft, rainfall processes should
be pretty efficient as this rain moves through. Indeed, note that are
pockets of moderate to even heavy rain embedded within the broader
area of precipitation, with some spots reporting a quarter to
upwards of a third of an inch of rain in an hour. While the front is
slow-moving, it will make enough forward progress to limit any
flooding threat beyond ponding of water in poor drainage areas. The
rain still looks to exit to our east by early afternoon; total
rainfall amounts through that time should generally be in the 0.50
to 1.0 inch range, with locally higher amounts possible where
heavier rain lingers. The St Lawrence Valley will remain on the
northern fringe of the rain, so rainfall there will be closer to a
quarter of an inch.
Drier air will follow the trough/boundary, and expect we`ll end up
with a fairly nice afternoon under partly to mostly sunny skies.
Highs will be much warmer than yesterday as we`ll top out in the mid
60s to mid 70s. This warmer and drier trend will carry over into
Tuesday. High pressure centered just to our south will allow for
lots of sunshine, fair weather, and highs in the upper 70s to mid
80s. A cold frontal boundary will approach from Canada late in the
day, but any showers associated with this will hold off until dark.
A 45+ kt 850 mb jet ahead of this front will move over northern
areas Tuesday afternoon, and with steep low level lapse rates
resulting in efficient mixing, winds will likely become quite breezy,
especially in the St Lawrence Valley and along the northern
Adirondacks. Gusts of 30 to 40 mph will be possible in these areas
Tuesday afternoon. Elsewhere, gusts should remain 20 to 30 mph.
KEY MESSAGE 2: Upper low pressure will slowly pivot across eastern
Canada and the Maritimes Wednesday through Thursday, keeping us
under northwest flow. A series of upper shortwave troughs and
surface boundaries/fronts will rotate around the upper low, bringing
occasional chances for showers through mid week. These features are
hard to pinpoint in timing, placement, and intensity, so really
can`t say for that any one day will be dry vs another, so have gone
with 15-30% PoPs for much of the Wednesday through Thursday
timeframe due to the uncertainty. Regardless, any showers that do
develop should remain scattered and fairly light in nature. We do
anticipate the start of a cooling trend; while highs on Wednesday
will be in the 70s to near 80F, Thursday will be noticeably cooler
with temperatures remaining in the 60s in most spots.
KEY MESSAGE 3: No big changes to the forecast rationale for late in the
week into the weekend as an upper level trough digs southward into
our region before slowly kicking to our east, supporting cool and
mostly cloudy conditions. The global ensemble mean shows this upper
level low and associated greatest 500 millibar height anomalies (per
AIGFS as low as the climatological 2nd percentile) overhead Saturday
morning and then weakening/migrating to our east thereafter as
anticyclonic flow develops. As such, the period in which this trough
is either upstream or overhead will provide us with at least
scattered to numerous showers due to strong synoptic scale lift,
especially if a surface cold front sharpens coincident with the
system. PoPs remain in the chance category due to uncertainty in
timing/location of this trough, but the pattern looks favorable rain
to occur at some point, especially on Friday and Saturday. The
latest cluster analysis reflects the timing uncertainty. Two of the
four upper air patterns, making up the majority of ensemble
membership, show similar progression of anomalous 925 millibar
temperatures and precipitation chances, but high 6 hourly
probabilities of rain are offset by about 12 to 18 hours. While
chances of rain decrease on Sunday, per some of the latest guidance
showing a very slow exit of the trough rain cannot be ruled out this
far out in time.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Through 06Z Tuesday...Expected changeable flight conditions due to
fluctuating ceilings and intensities of rain as a plume of
widespread showers gradually shifts eastward over the airspace
through the morning. Moderate rain with embedded heavier elements
will affect all sites except for MSS, for about two to four hours
within the 06Z to 12Z period with otherwise light rain intensity.
Additionally, upstream observations and model soundings suggest
within lighter rain ceilings could lower, especially with decreasing
winds towards 12Z. While all sites will likely have temporary IFR
conditions, greatest chances of prevailing IFR ceilings appears to
be at sites including MSS, SLK and RUT. Winds will be largely
light as the precipitation-inducing front moves through. Breezy
conditions with about 10 to 15 knots of southeasterly winds at RUT
will diminish as precipitation expands over the terminal. As drier
air moves in from the west between 12Z and 18Z and clouds scatter
soon after, winds will gradually shift westerly and increase into
the 7 to 10 knot range, then trend southwesterly after 00Z.
Outlook...
Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. Slight chance SHRA.
Wednesday: VFR. Slight chance SHRA.
Wednesday Night: VFR. NO SIG WX.
Thursday: Mainly VFR, with local MVFR possible. Slight chance
SHRA.
Thursday Night: VFR. Slight chance SHRA.
Friday: VFR. Chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Hastings
DISCUSSION...Hastings/Kutikoff
AVIATION...Kutikoff
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