129
FXUS61 KBTV 141104
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
704 AM EDT Tue Apr 14 2026
.WHAT HAS CHANGED...
As of 344 AM EDT Tuesday...
Confidence in severe weather has increased across portions of
central and southern Vermont today as a Slight Risk (2 out of
5) has been added by the Storm Prediction Center for possible
damaging winds.
&&
.KEY MESSAGES...
As of 344 AM EDT Tuesday...
1. Showers with embedded thunderstorms likely today, with a
couple stronger storms possible, mainly south of US Route 4.
Damaging winds will be the main threat with any possible severe
storms.
2. Additional precipitation chances and warm temperatures will
continue through the end of the work week with some embedded
thunderstorm chances in the afternoons.
3. A more amplified weather pattern and shortwave will lead to
unseasonably warm conditions and scattered rain showers at the end
of the week.
4. A round of widespread showers Saturday night and Sunday will
usher in a sharply cooler period early next week.
&&
.DISCUSSION...
As of 344 AM EDT Tuesday...
KEY MESSAGE 1: An area of enhanced convection associated with an MCS is
currently tracking across the Great Lakes this morning with
widespread lightning as it approaches our area. This area of energy
is riding along a nearly stationary boundary that is draped across
our region with a weak surface low centered over Lake Michigan.
This sfc low will track near the International Border by this
afternoon bringing widespread shower and thunderstorm chances.
The latest SPC day1 outlook shows a Slight Risk (2 out of 5)
south of a line from Saranac Lake, NY to Lebanon, NH, with a
Marginal Risk (1 out of 5) for the rest of the region. The main
threat with any thunderstorms today will be potentially damaging
gusty winds.
A cold front associated with the sfc low will begin to organize
itself into a broken line of showers as early as noon today across
the St. Lawrence Valley. Instability ahead of the line remains
somewhat uncertain for most of the region with high clouds and a
lack of diurnal heating time as the boundary slides east. HRRR and
RRFS models denote an earlier boundary progression between 3 and 5
PM in the CPV, whereas the NAM3k continues to favor a later arrival
to the CPV between 6 PM and 8 PM, which the latter would be
favorable for stronger storms. Any instability in the warm sector
will be maximized in the southern Champlain Valley and southern
Vermont where some clearing and higher temperatures into the 70s
will allow Sfc CAPE to rise to 400-600J/kg progged in the HRRR,
supported by HREF probability maximums of 40-60% across
southern Vermont. Furthermore, these warming temperatures will
allow lapse rates to rise to 7-8C/km supporting areas of
thunderstorms development. A low level jet across the
International Border will help support 0 to 6 km shear to 40 to
50 knots mainly north of US 4, but with pockets of embedded
40-50 knots of shear in southern Vermont. This highlights the
strongest winds are north and the highest instability is south.
These pockets of embedded higher shear will be colocated with
curving hodographs and around 200 m2/s2 0 to 3 km SRH which
would support some isolated areas of rotation. However, failure
modes do exist, with convective blowoff limiting instability
potential, LCLs to above 1000 m, and the innate climatology of
rotation for our region that would not favor any supercells this
time of year. Localized heavy rain cannot be ruled out with
Pwats around 1 to 1.25 inches, but progressive storm motion, and
lack of training storm signals keeps this threat level low.
This will be a nowcasting type of day as we watch how the
environment evolves throughout the day to see how robust
convection will be. For now the greatest action will likely be
across Rutland/Windsor Counties with the potential for damaging
wind gusts above 60 MPH, with most of the overall action south
of our CWA.
KEY MESSAGE 2: An active weather pattern is expected through mid week
into late week as a nearly stationary boundary becomes draped across
the region north of a ridge over the Southeast. Multiple shortwaves
will ride along this ridge under westerly flow producing additional
chances for precipitation through the late week. The stationary
boundary will likely fluctuate from day to day depending on both
mesoscale features like residual convective prior day activity and
synoptic flow. These changes will have significant impacts on
temperatures and daytime instability for both Wednesday and
Thursday. Latest trends indicate the Wednesday system arriving
during the late morning into early afternoon with embedded
thunderstorms possible. Given the timing thunderstorm chances will
be limited, but the best chances will be across central and southern
Vermont. This setup will be similar to todays thunderstorm
potential, but the boundary may setup a bit south of todays, which
would limit the available instability. HRRR/NAM3 profiles show
weaker lapse rates with a low LCL and potential strong inversion
above 500 ft. There will be little change in the overall airmass
with temperatures still rising into the upper 60s to low 70s in
southern Vermont and in the upper 50s to low 60s elsewhere. Thursday
will will almost be a carbon copy of Wednesday, and as usual,
instability will be the driving factor for any thunderstorm
potential. Trends for Thursday have been towards some morning
convection which will limit the afternoon instability and
thunderstorm threat, but with these setups, boundary motion is hard
to nail down, and where and if these thunderstorms develop is still
uncertain. Regardless, most of the area can expected rounds of
showers and embedded thunderstorms and warm temperatures through the
late week.
KEY MESSAGE 3: A quick-hitting shortwave will bring some rain showers
and potential embedded thunderstorms, mainly in southern Vermont, on
Friday as guidance indicates 925mb temperatures could reach 13-17 C
Friday afternoon. Due to this and decreasing clouds, forecast
surface temps are as high as the 60s and lower 70s, with non-zero
instability values projected. Probability of measurable
precipitation runs about 30-60% Friday afternoon, likely realized as
spotty showers everywhere and a few rumbles of thunder in
central/southern Vermont. Lows Friday night should remain mild in
the 40s and lower 50s, with only a brief period of high pressure
between systems late Friday night and Saturday morning. The next
chance for precipitation arrives late Saturday afternoon and evening
as a larger frontal system approaches. Despite increasing clouds,
temperatures are expected to again rise above seasonable normals
Saturday, reaching into the 60s in strong southerly flow and modest
warm air advection.
KEY MESSAGE 4: A large frontal system, centered over Ontario and the
Hudson Bay Saturday night, will drag a cold frontal boundary through
the forecast area into Sunday. Lows Saturday night in the 40s and
lower 50s will fall into the upper 20s to mid 30s on Sunday night,
and highs Sunday in the mid 50s to lower 60s become upper 30s to mid
40s Monday as cooler air spills into the region on northwesterly
flow behind a secondary cold front. Probabilities of measurable
precipitation in six hours are about 50-65% by Sunday afternoon,
though probabilities of rainfall 0.50" within 24 hours during this
period is around 10-30%. Thunderstorms are most likely Sunday
afternoon in northern New York when warmth lingers, but the timing
of instability, warmth, and forcing do not align favorably for
widespread t-storms in this system as the best forcing occurs at
night. Sunday night and Monday, as temperatures fall, there is the
potential for some snow showers, mainly at higher elevations, before
the arrival of drier air behind a secondary front tapers off precip.
High pressure keeps weather quieter and cool toward the middle of
next week.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Through 12Z Wednesday...Low clouds and fog will disperse and
lift this morning. Showers with embedded thunderstorms are
likely today, with a couple stronger storms possible. Damaging
winds will be the main threat with any severe storms. An area
of enhanced convection is currently tracking across the Great
Lakes this morning with widespread lightning as it approaches
our area from the west. Question remains on how much clouds
clear up throughout the day today. Most likely seeing cigs lift
to widespread VFR levels until showers and thunderstorms come
through this afternoon and evening, lowering cigs back to MVFR
and potentially IFR. Vis will also be limited in showers and
t-storms, though confidence is lower on the exact timing of
t-storms and their lowered visibilities. Wind gusts out of the
southwest 15-25 knots for most sites are likely with the passage
of the showers and t-storms in the afternoon. Some LLWS is also
expected as southwest to west winds at 2000 ft agl increase
along the showers/storms, around 16Z-20Z Tuesday onwards. After
the showers/storms pass through each site, ceilings are
expected to lower to widespread IFR by around 00Z Wednesday.
Outlook...
Wednesday: Mainly VFR, with local IFR possible. Likely SHRA,
Slight chance TSRA.
Wednesday Night: MVFR/IFR conditions possible. Chance SHRA,
Slight chance TSRA.
Thursday: Mainly MVFR, with areas IFR possible. Likely SHRA,
Slight chance TSRA.
Thursday Night: MVFR/IFR conditions possible. Chance SHRA.
Friday: MVFR/IFR conditions possible. Chance SHRA.
Friday Night: Mainly VFR, with local MVFR possible. Slight chance
SHRA.
Saturday: MVFR. Slight chance SHRA.
&&
.CLIMATE...
As of 344 AM EDT Tuesday...
Incoming warmer air is presently forecast to approach daily
record values. The most likely dates for near or broken records
will be today with mild overnight air leading to high minimum
temperatures. Below are some of the daily records in jeopardy of
being broken (current forecast at or within 3 degrees of the
record).
Record High Minimum Temperatures:
April 14:
KBTV: 54/2023
KPBG: 51/1964
KSLK: 47/1964
&&
.EQUIPMENT...
The Colchester Reef meteorological station is out of service.
This site is not serviced by the NWS. An estimated return to
service is May 1st. Please contact us if you observe winds
significantly deviating from the recreational forecast.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Danzig
DISCUSSION...Storm/Danzig
AVIATION...Storm
CLIMATE...NWS BTV
EQUIPMENT...NWS BTV
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