FXUS61 KBTV 261716

AFDBTV



Area Forecast Discussion

National Weather Service Burlington VT

116 PM EDT Thu Jun 26 2025



.SYNOPSIS...

Much cooler temperatures with plenty of clouds will impact our 

region today, along with a few light rain showers. Any rainfall 

amounts will be light and generally under a tenth of an inch. An 

active period of weather is anticipated late Friday into Saturday 

with several rounds of localized heavy rainfall expected, along with 

some localized flash flooding possible. Drier and warmer weather 

returns by early next week.



&&



.NEAR TERM /THROUGH FRIDAY/...

As of 1014 AM EDT Thursday...Just a few minor adjustments needed

to the forecast this morning. Increased cloud cover continues to

stream into the region, and despite the radar returns

precipitation is not quite making it to the surface. As the

afternoon progresses, some light precipitation can be expected,

but the current forecast has this covered. 



Previous discussion below:

GOES-19 water vapor shows fast confluent flow aloft acrs our 

cwa which is in btwn a strong mid/upper lvl ridge over the se 

conus and departing trof over eastern Canada. A pocket of 

enhanced mid lvl moisture associated with decaying MCS wl dive 

southeast acrs our cwa today. However, the combination of 

warming cloud tops on the GOES-19 IR satl imagery, decreasing 

reflectivity structure on radar and drier air at the llvls 

undercutting deeper moisture aloft wl result in light qpf today.

Have kept the general idea of chc pops with qpf <0.10". North 

winds, plenty of clouds, and scattered light precip wl keep 

temps in the mid/upper 60s to mid 70s acrs our fa. Tonight 

latest 00z HRRR indicates slightly stronger progged composite 

reflectivity acrs parts of our cwa, so have bumped pops into the

40- 60% range, especially early this evening. Once again, 

precip might have difficulties reaching the ground, as drier air

near the sfc is advecting into our region on north/northeast 

winds around sfc high pres over northern Maine. Comfortable lows

in the upper 40s to near 60F anticipated. Friday looks 

unsettled again as a warm frnt tries to lift northward, but runs

into dry air. Guidance is struggling on the areal coverage and 

placement of potential precip attm, so have chc east to low 

likely west in the morning, increasing to 60 to 80% in the aftn 

from west to east. The highest probability of precip looks to be

over northern NY, but some guidance has greatest potential 

north of our cwa on Friday. If this trend prevails, lowering of 

pops maybe needed acrs portions of our cwa. Any qpf on Friday wl

be in the 0.10 to 0.25" range with some localized higher 

amounts possible in any convective elements. Highs in the mid 

60s to lower 70s.



&&



.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...

As of 316 AM EDT Thursday...An active period of wx anticipated with

several rounds of localized heavy rainfall likely, along with

isolated flash flooding possible. Still considerable spread in exact

placement of heaviest qpf axis and associated precip amounts, but

synoptic scale setup remains unchanged with latest 00z guidance. If

current trends continue a flood watch maybe needed for portions of

our area late Friday into Saturday for rainfall amounts in the 1.5

to 2.5" with localized amounts near 4.0" possible.



The large scale pattern indicates deep mid/upper lvl ridge acrs the

se conus with developing south/southwest flow in the 850mb to 300mb

layer, which helps to advect pw values in the 1.50" to 1.80" range

into our cwa. 00z GFS shows pw values approaching 2.0" by 06z Sat

acrs our fa, which is 150% to 200% of normal for late June. In

addition to very deep moisture profiles, an un-seasonably strong

250mb jet of 140 to 160 knots wl be lifting acrs southern Canada,

placing our northern cwa in the favorable right rear quadrant for

promotinglarge scale ascent and strong ulvl divergence. Meanwhile,

in the 925mb to 700mb layer a sharpening llvl gradient wl be present

acrs our region, helping to enhance bands of favorable 850 to 700mb

fgen forcing and promoting localized heavy rainfall rates. This

narrow axis of favorable fgen forcing is extremely difficult to

predict and correlates very closely with axis of max qpf. If the

strengthening 850mb jet pushes warmer air further northward and

better/deeper instability develops overhead, the axis of heaviest

rainfall would be located over southern Canada, which is supported

by several pieces of guidance. However, if the sharp boundary and

associated instability is acrs our fa, along with the nose of the

850mb jet, the heaviest precip would be centered acrs our

central/northern cwa. The placement of this 850mb jet is key for

enhanced llvl moisture convergence and development of elevated

instability, especially on Saturday, when better dynamics aloft

arrive. Its the elevated instability parameters in combination of

warm cloud depths over 12,000 feet, which could enhance rainfall

rates and cause localized flash flooding. The MCS and associated

convection crntly over central NE is progged to angle our way and

ride along a nearly stationary boundary draped somewhere acrs the ne

conus late Friday into Sat. Based on EPS and GEFS and averaging the

latest deterministic guidance, the greatest potential for the

heaviest rainfall would be near the International Border over

northern NY into central/northern VT. WPC continues a slight risk (2

out of 4) acrs this region, which looks reasonable. Highs on

Saturday wl be in the mid 60s east to mid 70s west with increasing

sfc dwpts/humidity values.



&&



.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...

As of 316 AM EDT Thursday...Rainfall appears likely to linger across

Vermont Saturday evening but global deterministic guidance remains

split on how fast the precipitation exits. Some of the guidance

depicts the frontal boundary getting hung up across the Green

Mountains with light rain continuing into Sunday morning while

others have a more progressive frontal boundary allowing rainfall to

end sooner. The ensembles seem to be a split of the two showing rain

ending during the pre-dawn hours on Sunday but any additional

rainfall during this timeframe is likely to be light as the highest

PWAT air mass slides off to the east. Still, runoff from higher

terrain will continue during this time frame and could allow for

some additional flood concerns depending on where exactly the

heaviest rain axis sets up on Friday and Saturday.



Brief ridging on Monday will allow for some peaks of sunshine and a

brief period of dry weather in the wake of a warm front.

Temperatures on Monday will warm back above seasonal normals with

highs in the 80s to near 90 degrees in the wider valleys. Subsidence

from mid-level ridging should help prevent any pop-up afternoon

thunderstorms on Monday. As we head into Tuesday, the weather once

again looks to be rather unsettled. A cold front is slated to move

across the region during the day on Tuesday but with plenty of

timing discrepancies between deterministic and ensemble guidance. As

usual, it does appear that the approaching cold front on Tuesday

will come through piece by piece with a pre-frontal trough Tuesday

morning, followed by the upper level supper, then the surface cold

front, and ultimately the low level wind shift. Given these features

are out of phase, we could see some strong storms but the

possibility for severe storms on Tuesday seems pretty low. There is

plenty of time for this to change so we will be watching this

closely over the next several days. Following the cold front, a

longwave trough appears likely to situate across the region which

will bring seasonal temperatures with the chances for daily showers

and maybe a rumble of thunder or two.



&&



.AVIATION /17Z THURSDAY THROUGH TUESDAY/...

Through 18Z Friday...Overall, VFR conditions and light winds 

are expected through the TAF period. Some light rain showers 

are generally expected between 18Z and 00Z across our terminals

but given that the rain is expected to fall out of a 10kft 

deck, much of it will likely evaporate prior to making it to the

ground. Any rain that does make it down to the ground will be 

light and likely won't have any impact on the flight category

expect some brief periods of MVR Vis. MPV could see some early

morning fog if the mid level deck clears out, with some pre-dawn

IFR conditions. Winds will out of the northeast this afternoon 

at 5-10 knots, becoming light and variable overnight before 

becoming southeasterly at 5-10 knots tomorrow.



Outlook...



Friday Night: Mainly VFR, with local MVFR possible. Definite

SHRA, Slight chance TSRA.

Saturday: Mainly MVFR, with local IFR possible. Definite SHRA,

Slight chance TSRA.

Saturday Night: Mainly MVFR, with local IFR possible. Chance

SHRA, Slight chance TSRA.

Sunday: Mainly MVFR, with local IFR possible. Slight chance SHRA.

Sunday Night: Mainly VFR, with local IFR possible. NO SIG WX.

Monday: Mainly VFR, with areas MVFR possible. Slight chance SHRA,

Slight chance TSRA.

Monday Night: Mainly VFR, with local MVFR possible. Likely SHRA,

Slight chance TSRA.

Tuesday: MVFR/IFR conditions possible. Likely SHRA, Slight chance

TSRA.



&&



.HYDROLOGY...

The latest NWS forecast continues to support the idea of several 

rounds of moderate to locally heavy rainfall will be possible

late Friday into Saturday. With boundary position and movement

at play, the exact placement of heaviest rainfall remains 

somewhat uncertain, though there is fairly decent consensus that

the focus will lie across far northern NY into the northern 

third of Vermont. Given near normal streamflows and 0-40cm soil 

moisture profiles, we do have some wiggle room/capacity to 

handle some of the runoff. As such, widespread mainstem river 

flooding is not expected at this point with the emphasis more on

the flash flood threat in small streams/watersheds in steep 

terrain. However, a few of the smaller rivers may see sharp 

rises by Saturday. Our current precipitation forecast indicates

1.5 to 2.5 inches, with localized higher amounts likely across 

the higher terrain in the aforementioned areas. It needs to be

stated, a significant variability in rainfall distribution 

often occurs during convective events, so exact precip amounts

and placement are very challenging. Current 3/6 hour flash 

flood guidance of between 2 and 3.5 inches all appears 

reasonable at this time.



&&



.BTV WATCHES/WARNINGS/ADVISORIES...

VT...None.

NY...None.



&&



$$

SYNOPSIS...Taber

NEAR TERM...Kremer/Taber

SHORT TERM...Taber

LONG TERM...Clay

AVIATION...Verasamy

HYDROLOGY...NWS BTV

