FXUS61 KBTV 250555
AREA FORECAST DISCUSSION
National Weather Service Burlington VT
155 AM EDT Sat May 25 2019
Today will start of dry with just some high clouds moving in,
but rain showers will develop later this afternoon into this
evening as a warm front pushes through. Showers will be heaviest
in the early overnight hours tonight, when a rumble of thunder
can`t be ruled out as a trough moves through. The line of
showers will clear the area by Sunday morning, but some
scattered showers with a slight chance of thunderstorms will
redevelop Sunday afternoon. Sunday night through Monday night
will be drier as high pressure builds over the area.
Temperatures today and Sunday will be in the 70s, then Monday
and Tuesday will cool down a bit with highs expected in the 60s.
.NEAR TERM /UNTIL 2 PM THIS AFTERNOON/...
As of 135 AM EDT Saturday...Microphysics imagery off of GOES 16
is showing fog beginning to build in across the North Country as
skies have cleared. Saranac Lake is the only place reporting fog
thus far but over the next few hours fog will continue to
develop. Based on the observation in Saranac Lake, any fog that
does develop could be dense as visibilities have been bouncing
between a half and a quarter of a mile.
Previous Discussion...Low pressure continues to pull away from
the region this afternoon, moving south of Nova Scotia and out into
the Atlantic. Moisture associated with this system will likewise
exit to the east, with high pressure building across the North
Country tonight into Saturday. Hence, clouds will dissipate this
evening as we lose daytime heating. This with light winds will allow
for good radiational cooling; lows will be in the mid to upper 40s
for most, though the usual cold spots in the Adirondacks and
Northeast Kingdom will bottom out around 40. Clouds will increase
Saturday morning ahead of a warm front lifting in from the
southwest. Precipitation associated with the front will follow,
moving into our NY areas mid afternoon, and into Vermont late
afternoon into the early evening hours. Initially, warm air
advection aloft will keep us capped, so don`t anticipate any
thunderstorms through most of the daylight hours. Highs will range
from the upper 60s to lower 70s. Deep moisture plume will stream
northward into the region late tomorrow into tomorrow night ahead of
an approaching cold front. PWATs are progged to exceed 1.50 inches
from the Champlain Valley westward. Some elevated instability will
spread into northern NY, allowing thunderstorms to develop. These
will interact with the copious moisture and warm cloud depths of 10+
kft to produce heavy rain at times through the evening hours. The
best moisture and instability starts to get shunted to the southeast
after midnight as the prefrontal trough moves through, so the threat
will wane as we head toward sunrise Sunday morning. Rainfall totals
through Saturday night will be a third to around a half an inch in
Vermont, while some NY locations could see upwards of an inch.
Higher amounts will be possible in any convection. Overnight lows
will be in the 50s to around 60.
.SHORT TERM /2 PM THIS AFTERNOON THROUGH SUNDAY NIGHT/...
As of 250 PM EDT Friday...Front clears through the area during
the morning to early afternoon hours on Sunday with little
fanfare. Maintained very low end pops (20-30%) for showers or an
isolated storm through the morning hours to account for any
scattered activity but forcing is rather weak along the wind
shift so most of the day should turn out dry with highs
seasonably mild in the 70s to locally near 80. Then trending
mainly clear Sunday night under building high pressure with lows
in the 40s to lower 50s.
.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 250 PM EDT Friday...H5 ridge then crests atop the region
on Monday with sunny skies and mild temperatures in the 60s.
This will be the best day of the workweek for outdoor
Thereafter the general wx trends unsettled as the forecast area will
reside on the northern edge of deep layer southeastern CONUS
ridging. Periodic shortwave wave passages embedded in fast west to
southwesterly flow aloft should ensure near daily chances of showers
and occasional storms, though inherent timing uncertainties in day 4-
7 forecasts leads me to keep pop values reasonable side (40-60%) at
this point. Best threat of storms looks, at least at this point to
occur on Wednesday into Thursday when the combination of heating and
moisture looks the greatest. Temperatures in general to average
within 5 degrees of late May seasonal norms.
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
Through 06Z Sunday...High pressure overhead is allowing for the
development of some patchy BR/FG, locally reducing visibilities
to IFR/LIFR conditions. Most TAF sites will see variable
visibilities between 2SM and 6SM through 10Z, but KMSS and KSLK
will see 1/4 SM to 2SM BR/FG prevailing through 10Z. After 10Z,
expecting all TAF sites to quickly trend VFR as fog mixes out. A
warm front will work through the region today, spreading showers
over northern NY starting between 18Z and 20Z, and over VT
starting between 19Z and 22Z. These showers will be accompanied
by deteriorating ceilings through the end of the TAF period and
localized MVFR visibilities within heavier showers. Winds will
be calm overnight, becoming southerly 6-12 kts after 18Z.
Sunday: Mainly VFR, with local MVFR possible. Slight chance SHRA,
Slight chance TSRA.
Sunday Night: VFR. NO SIG WX.
Memorial Day: VFR. NO SIG WX.
Monday Night: VFR. Slight chance SHRA.
Tuesday: MVFR/IFR conditions possible. Likely SHRA.
Tuesday Night: Mainly VFR, with local IFR possible. Chance SHRA,
Slight chance TSRA.
Wednesday: Mainly VFR, with local IFR possible. Chance SHRA,