776
FXUS61 KBTV 191753
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
153 PM EDT Tue May 19 2026
.WHAT HAS CHANGED...
As of 1045 AM EDT Tuesday...
Early morning showers have temporarily stabilized the
environment with more clouds and impacting the diurnal curve.
Adjusted near term data and precipitation chances over the next
12 hours based on current radar and incoming high res data.
&&
.KEY MESSAGES...
As of 727 AM EDT Tuesday...
1. Unusually warm temperatures continue today into Wednesday
before a cold front moves through the region bringing much cooler
conditions by Thursday and Friday.
2. Strong to locally severe thunderstorms possible this
afternoon and evening with more widespread showers possible
overnight into Wednesday.
3. Breezy to gusty winds are expected today through Wednesday.
4. Seasonable temperatures and increasing chances of
precipitation expected for the weekend into early next week.
&&
.DISCUSSION...
As of 727 AM EDT Tuesday...
KEY MESSAGE 1: Heat will continue today with 925mb temperatures
favored to warm into the 20-24C range. This is down from
yesterday, but the warmer start this morning will continue to
promote hot conditions. Maximum temperatures are favored back
into the mid and upper 80s with 90 within reach for a few select
locations. Flow will be swinging southwesterly, so Burlington
may get a marginal reprieve as air moves across the colder
surface of Lake Champlain; upper 80s are favored here.
Conversely, eastern slopes will have an increase in temperatures
from this wind direction that will promote increased
compressional warming off the terrain of the Adirondacks and
Greens. 90-93 degrees is more probable for eastern Essex County,
NY and for the Springfield, VT area. Around 90 is possible for
portions of Rutland/Addison Counties as well. Temperatures are
expected to drop by 10-15 degrees for Wednesday, but remain 5-10
degrees above seasonal averages. Warmest spots will be in
southern Vermont where there will be potential for more heating
ahead of the boundary. Highs in the 70s are forecast with low
80s for southern Vermont locations. Northwest flow will dominate
behind the front bringing sharply cooler temperatures for
Thursday and Friday with highs likely in the mid/upper 50s, then
60s respectively. This will be around 10 degrees below seasonal
averages and around a 30 degree departure from yesterday and
today`s high.
KEY MESSAGE 2: A conditional threat for strong to severe
thunderstorms remains as heat continues while dew points rise.
Highs in the mid/upper 80s to 90s coupled with dew points in
the upper 50s to mid 60s would support a few stronger variety
storms. Should any storms fire off, it`s probable that outflows
would be sufficient to ignite other cells, especially if they
interact with lake breeze or move into convent flow around
terrain. The biggest issue will be a trigger. Models are showing
a subtle 500mb trough moving through late this morning and
early afternoon which is what some of the CAMs are highlighting
as a trigger. There should be ample cloud breaks to allow for
heating which will put the focus on shower/cell initiation over
higher terrain. Have increased chances of showers over the
Adirondacks coincident with trough timing and as temps on the
slopes rise to near 80 degrees which aligns with about noon. The
biggest concern will be winds (15%) with a stout low level jet
and deep layer of 40+kts extending from 2500-15000ft. There will
be about a 5% chance of any storm developing hail this
afternoon. The continued absence of strong low level shear means
the tornadic threat is very low. Finally, can`t rule heavy rain
completely out with PWATs in excess of 1.5". If storms fire and
a persistent boundary can set up, training cells could occur
resulting in localized heavy rainfall. The threat for stronger
storms will end around sunset with loss of heating and decrease
further behind the prefrontal trough overnight Tuesday.
More synoptically induced precipitation is expected as the front
begins to moves through tonight along a prefrontal trough and
Wednesday as the surface front moves through.
KEY MESSAGE 3: Winds will be breezy through Wednesday given
periods of low level jet passages and a moderately strong
thermal/pressure gradient along and behind Wednesday`s front.
Gusts 20-35 mph are likely with highest gusts in the northern
Champlain Valley and along the Highway 11 corridor in the
vicinity of Malone/Ellenburg, NY. Gusts to 40 mph are possible
should mixing be more pronounced; model soundings show robust
southwest flow aloft with a deep 35-45kt layer 2500-15000+ft.
Some model guidance is suggesting a narrow potential at gusts to
40 mph for portions of northern New York tonight, but this will
be highly dependent on convection which is less certain. These
winds will result in rough lake conditions on Lake Champlain.
Lighter winds return Thursday as high pressure moves across the
region.
KEY MESSAGE 4: There continues to be considerable differences in
both ensembles and deterministic models in how shower chances
play out for the upcoming holiday weekend. Ensemble members of
both the GEFS and ECMWF are roughly split equally on whether
waves of precipitation will cross the area Saturday into Sunday.
The deterministic ECMWF also favors a wetter solution.
Meanwhile, the remaining ensemble members along with the GFS and
CMC keep ridging more firmly in place, with the axis running
just to our east. This would keep rain shunted to our south and
west through the day Saturday and most of Sunday, then trending
rainy for Memorial Day. With this much uncertainty, have stayed
with the NBM solution for now. Either way, temperatures will be
seasonable with highs mainly in the 60s and lows in the 40s.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Through 18Z Wednesday...Conditions are mainly VFR for the next
several hours. Spotty showers and thunderstorms will be possibly,
mainly at KRUT from 19z-21z, and then a separate batch is possible
at KMSS, KSLK, and KPBG from about 03z-07z. Any shower or storm
could briefly reduce visibility to 2-4SM for 10-30 minutes.
Ceilings will mostly remain at or above 5000 ft agl with
scattered cumulus. More appreciable drops in ceilings will be
possible after 06z with ceilings trending towards 1500-4500 ft
agl. Winds throughout the period will be southwesterly at 7-15
knots with intermittent gusts of 20-25 knots possible, mainly at
KMSS. 2000 ft agl winds increase between about 04z and 12z,
with west winds at 35-45 knots, and LLWS will be possible for
almost every terminal. Flight conditions will generally improve
after 12z Wednesday, but there could be some bouncing or pauses
between several weak boundaries sliding southeast into
Wednesday along with a shift to west or west-northwest winds.
Outlook...
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. NO SIG WX.
Thursday Night: VFR. NO SIG WX.
Friday: VFR. NO SIG WX.
Friday Night: VFR. Slight chance SHRA.
Saturday: VFR. Chance SHRA.
Saturday Night: VFR. Chance SHRA.
Sunday: VFR. Chance SHRA.
&&
.MARINE...
As of 236 AM EDT Tuesday...
A Lake Wind Advisory remains in effect for the Broad Waters of
Lake Champlain. Winds are expected to increase this morning out
of the south with sustained speeds 15 to 20kts and gusts around
25kts. These stronger winds will continue through 8 AM and will
diminish to 15 knots or less until the early afternoon; winds
then increase again as faster winds aloft mix to the surface.
Gusts in excess of 20kts are probable before flow turns more
southwesterly. South winds return tonight with stronger gusts
possible. A front will pass through the region Wednesday
resulting in a wind shift out of the north with gusts up to
30kts.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Boyd/Haynes
DISCUSSION...Hastings/Boyd
AVIATION...Haynes
MARINE...Clay
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