FXUS61 KBTV 260245
Area Forecast Discussion
National Weather Service Burlington VT
1045 PM EDT Fri May 25 2018
Unsettled weather is expected for the Memorial Day Weekend as a
cold front moves slowly southward out of Canada later tonight
and Saturday. This will allow showers to move across the
area...especially over northern New York and the northern half
of Vermont. For Saturday afternoon...the threat of
thunderstorms will exist over central and southern Vermont and
parts of the northern Adirondacks in New York. Cooler and drier
weather moves into Vermont on Sunday...but there will still be a
threat of showers and thunderstorms across portions of northern
New York as an upper level trough of low pressure moves toward
the region. This feature will move across the area on Memorial
Day and will continue to bring a chance of showers to the entire
.NEAR TERM /THROUGH SATURDAY NIGHT/...
As of 1042 PM EDT Friday...Only minor adjustments to PoPs next
1-3 hrs to account for ongoing high-based showers and
associated radar trends, with showers generally moving ESEWD at
20-25kts. Have seen rainfall up to 0.10" in spots this evening
associated with ongoing activity. Cloud bases generally 6-8kft,
and dry sub-cloud layer is generating some evaporative cooling
and associated wind gusts locally up to 25kts. Most of the
activity is expected to shift east of the area by 04Z or so,
with lesser chances for rain showers lingering during the pre-
dawn hours. Overnight lows generally expected in the upper 50s
to lower 60s across the North Country with generally S-SW winds
Previous Discussion...Mid-level clouds continue to move across
the area this afternoon along with a few sprinkles. Eventually
we will see better chances for showers and possibly a
thunderstorm across the northern tier of our area as upstream
convection over southeast Ontario moves east-southeast into the
region tonight. Main frontal system remains back up across
southern Quebec Province and this feature will not move down
into our area until Saturday. It looks like surface front will
push just south of a Massena to White River Junction line
Saturday afternoon and sufficient instability should develop
along and south of this boundary for a better chance of showers
and possibly some thunderstorms. Of note is the 850 millibar
front is still up near the Canadian Border and it appears it
will be a focus for additional showers as well. So much of the
forecast area will have a chance for precipitation. Fronts
weaken Saturday night and any precipitation will weaken in
intensity and push eastward as flow aloft becomes more westerly
with time. Strong push of cooler air will take place late
Saturday night across Vermont as high pressure bring a more
maritime air mass into the region. Highs on Saturday will range
from around 70 near the Canadian border to the lower 80s over
southern areas south of the front. Lows Saturday night will
range in the upper 40s to upper 50s.
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
As of 321 PM EDT Friday...As mentioned in the near term
maritime air mass moves into the region on Sunday...especially
over Vermont and relative dry weather is expected for the day.
Cooler temperatures will exist with highs in the mid 60s to
lower 70s. A different story will take place over northern New
York as a more noticeable front becomes established out across
the Saint Lawrence Valley. Highs in northern New York will be in
the 70s to lower 80s and there will be a better chance of
showers and thunderstorms out across the Saint Lawrence Valley
in the afternoon. Higher precipitable water values in this area
will enhance the potential for heavy downpours with any of the
showers or storms. The upstream upper trough will gradually move
into the region Sunday night and while the threat of thunder
will decrease...sufficient dynamic support will exist for
showers to move eastward across the entire area late Sunday
.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 321 PM EDT Friday...At this time, not much has changed
from the previous forecasts. Overall, conditions look to be
unsettled Monday with above normal temperatures expected through
the period. High pressure dominates mid-week before more active
weather returns towards the end of the period...An upper-level
shortwave and associated warm front will push north during the
daytime hours on Monday. Showers are expected throughout the
day before the main front moves south Monday night. A chance of
thunder exists overnight Monday so have mentioned in grids but
the bulk of the forcing and instability should stay to our
north. Tuesday, skies will clear throughout the day as dry air
pushes south and high pressure builds in. Tuesday night lows
look to be the coldest of the period with clear and calm
conditions promoting near-normal temperatures in the mid 40s to
around 50. Wednesday looks to be sunny and summer-like with
temperatures warming into the upper 70s. Thursday will remain
dry, but warm even as clouds increase with temperatures pushing
low 80s for much of the area. The quiet stretch of weather will
become more active Friday as newly named subtropical storm
Alberto makes its way north. Models are still in good agreement
with tropical moisture moving northward, but are uncertain on
exact location of low and associated rainfall. Model`s have done
a flip-flop on position of heaviest precip with GFS now keeping
bulk just to our south over southern New England and ECMWF
bringing low pressure up the Ohio River valley with heavier rain
over western NY and international border...with such
uncertainty it certainly bears watching.
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
Through 00Z Sunday...Looking for prevailing rain showers all TAF
sites except KRUT thru 03Z or so with bands of showers moving
NW-SE. Rain is generally falling from mid- level overcast with
ceilings generally 6-8kft. Generally expect VFR conditions
throughout the night. Winds generally SW 5-10kts. However, with
dry sub-cloud layer, will see some gusty showers at times thru
03Z with winds briefly west 15G25KTS with evaporative cooling
effects ongoing. Generally carried VCSH for the balance of the
overnight in the TAFs with a chance of showers. Will see a
backdoor cold front approach from the north to northeast late
morning into the afternoon hours on Saturday. This will bring a
northerly wind shift, and locally NELY winds for MSS/PBG/SLK
during Saturday afternoon. Will also see another round of
prevailing rain showers and developing MVFR ceilings following
FROPA. Can`t rule out isold to scattered thunderstorms across
the Adirondacks into s-central VT south of the frontal bndry
during the peak afternoon heating hours on Saturday. We`ll
continue to monitor that threat for the TAF locations as we head
into Saturday and mesoscale details become more clear.
Saturday Night: Mainly VFR, with local MVFR possible. Chance
Sunday: VFR. Chance SHRA.
Sunday Night: Mainly VFR, with areas MVFR possible. Chance SHRA.
Memorial Day: Mainly MVFR, with local VFR possible. Chance SHRA.
Monday Night: Mainly VFR, with local IFR possible. Chance SHRA.
Tuesday: Mainly VFR, with local MVFR possible. NO SIG WX.
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. NO SIG WX.