880
FXUS61 KBTV 261822
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
222 PM EDT Sun Apr 26 2026
.WHAT HAS CHANGED...
As of 221 PM EDT Sunday...
Confidence continues to grow for critical fire weather conditions
Tuesday.
&&
.KEY MESSAGES...
As of 221 PM EDT Sunday...
1. Dry weather continues for the first half of the week with
critical fire weather conditions possible Tuesday due to gusty
winds and low relative humidities.
2. A soaking rain, starting Wednesday night but primarily on
Thursday, will be followed by an unsettled and cool weather pattern
Friday through the weekend.
&&
.DISCUSSION...
As of 221 PM EDT Sunday...
KEY MESSAGE 1: Surface 1021 mb high pressure is sitting over New
England this afternoon, and atmospheric pressure is expected to
increase over the next few days as an omega block remains in place.
Upper level ridging over the Ohio Valley and Great Lakes will shift
overhead tomorrow, resulting in light and variable winds at the
surface both this afternoon and tomorrow. Other than some drifting
high clouds, sunshine is also abundant this afternoon as a result,
which should last into the midweek. This will allow temperatures to
rise a little higher each day, with highs today in the lower to mid
60s this afternoon becoming the upper 60s and lower 70s both
tomorrow and Tuesday. A very dry layer will persist above the
boundary layer and efficient mixing could cause dew points to be
slightly lower than forecast on any given day. Therefore relative
humidity values will be around 20-35% each afternoon through Tuesday
with recoveries overnight to around 60-90%, depending on how well we
radiate out temperatures each night. Anticipated lows are in the
upper 20s to upper 40s through Monday night. Winds will increase
notably on Tuesday, with southerly gusts between 20 to 35 mph
possible, especially on mountaintops and in the Champlain Valley.
The winds, combined with the low relative humidity, are causing
critical fire weather conditions to become increasingly likely. By
Tuesday night, we expect the strong southerly flow to make for a
cloudier, milder night with lows in the 40s and lower 50s. There
could even be an isolated shower or two (probability 20-40%) in
northwestern New York on Tuesday night as a shortwave and associated
moisture crosses the region. The potential for a wetting rain
Tuesday night is about 10-30% in northern New York with highest
chance in the St. Lawrence Valley. More information about the
potential for rain mid to late week will be found in Key Message
Two.
KEY MESSAGE 2: Trends towards a mainly dry period, and a final warm day
for the week, continues for Wednesday. By evening, as a compact wave
of low pressure spreads widespread rain northeastward from Ohio
moving into the eastern Great Lakes, chances for precipitation will
increase in our region. Ensemble agreement on timing being primarily
overnight/early Thursday is noted by 6 hourly PoPs near 80% from 2
AM to 8 AM Thursday. This southern stream system, fed in part by the
Gulf waters/subtropical air, will tend to peter out as a secondary
low forms over the Mid-Atlantic region. This secondary low will
maintain a steady rain in Vermont for much of Thursday. While there
will be a feed of Atlantic moisture as precipitation begins to
become more consolidated in New England Thursday morning, the large
scale setup looks more favorable for eastern New England than
Vermont in terms of heavier rainfall potential. That being said, the
most recent run of the ECMWF Extreme Forecast Index shows a similar
signal for both Vermont and New Hampshire for a noteworthy rainfall
that comes up shy of extreme (values above 0.7 and below 0.8); this
was a notable increase from 24 hours ago, so it bears watching. The
pressure falls to our south/east will also minimize any potential
wind hazards with this system. While there will not be an upstream
block to stall out the low pressure area as it passes to our east,
its deformation/commahead and northward track favors rain chances
lingering into Thursday night and Friday. Given the extended dry
period we have had and the resulting low streamflows and river/lake
levels, no hydrological impacts are expected with basin average
rainfall somewhere in the 0.5" to 1.5" per ensemble (NAEFS, GEFS) 25-
75% percentiles. Greatest potential for those heavier amounts are in
central/eastern Vermont; lowest potential is over the Champlain and
St. Lawrence Valleys in New York.
As low pressure pulls northward into Maine, an upper level gyre will
reinforce a longwave trough over southern Canada/northeastern CONUS,
pulling in cooler air during this period. Blustery conditions will
occur with northwesterly or westerly flow through the period and
steep lapse rates, especially with any sunshine. Below normal
temperatures will occur, although nothing extreme is noted relative
to climatology. The coldest 925 millibar temperatures in the
ensemble mean are indicated as low as the 10th percentile in the
climatology Saturday morning with only a little moderation during
the weekend, especially Sunday afternoon. Relative to normal the
coolest weather will tend to be in southern/western portions of
northern New York. High temperatures each day will trend slightly
warmer, but even so valley highs in the mid 50s would still be about
10 degrees below normal.
As shortwave troughs circulate around, enhanced shower chances could
occur over the weekend, which would potentially result in some
mountain snow. At this time it looks like the orientation of the
gyre will keep steadiest precipitation focused either to our east or
to our north. As a proxy to mountain snow shower potential, the
probabilities of 850 millibar temperatures falling below freezing
will increase from west to east during the period. Per the AIGEFS,
Thursday evening chances surge above 80% in the Adirondacks through
the overnight hours, and surging from near 50% to 80% Friday morning
in the Green Mountains. Friday night into the rest of the weekend
850 millibar temperatures will certainly be below freezing.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Through 18Z Monday...VFR conditions will prevail for the next 24
hours with high pressure remaining in control. Winds will generally
be 4-8 knots, with some afternoon gusts up to 15 knots expected
through 22Z. Wind directions will be variable, driven mainly by
local terrain in the absence of any strong pressure gradients.
Outlook...
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. NO SIG WX.
Tuesday Night: Mainly VFR, with local MVFR possible. Slight
chance SHRA.
Wednesday: Mainly VFR, with local MVFR possible. Chance SHRA.
Wednesday Night: Mainly VFR, with local IFR possible. Likely
SHRA.
Thursday: Mainly MVFR, with areas IFR possible. Likely SHRA.
Thursday Night: Mainly IFR, with areas MVFR possible. Chance
SHRA.
Friday: MVFR/IFR conditions possible. Chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Storm
DISCUSSION...Kutikoff/Storm
AVIATION...Duell
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