Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 181134
Area Forecast Discussion
National Weather Service Burlington VT
734 AM EDT Sat Mar 18 2017
A ridge of high pressure moves through the region before giving way
to a weak system will pass to our south on Saturday into Sunday.
Temperatures slowly climb back toward normal over the rest of the
weekend into early next week before a mid week trough brings another
round of well below normal temps for the second half of the week.
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --As of 724 AM EDT Saturday...No significant changes to the
forecast, just some minor adjustments to the temperatures and
dew points. Other than that, the forecast is in good shape.
Previous Discussion...Mostly clear skies continue across area
as surface high pressure remains over the North Country. After a
cold start this morning, temperatures begin to rebound today as
light southerly flow and minimal cloud cover will lead to the
warmest temps in the past week with highs in the mid to upper
30`s across the region. Nearly bringing us back towards seasonal
Clipper low pressure system looks to swing just to our South on
Saturday and Saturday night. Models continue to support the idea of
just a slight chance of pops across southern zones with just a
potential dusting of snow Saturday night. Overnight lows will be
slightly below seasonal norms in the southern counties as cloud
cover should keep lows in the 20`s while up North temps will be in
the low teens but could easily drop into the single digits.
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.SHORT TERM /SUNDAY THROUGH MONDAY/...
As of 406 AM EDT Saturday...Generally quiet/dry weather
conditions through the short-term period. The 00z NWP model
suite has a good consensus on deepening surface low pressure
well south and east of New England during the day Sunday. This
will induce a dry, deep-layer northerly flow across nrn NY and
VT, with sfc high pressure eventually cresting over the North
Country Sunday Night into Monday. Anticipating mostly sunny
conditions on Sunday. With 850mb temperatures in the -6 to -7C
range, should see high temperatures generally 34-38F range. Good
radiational cooling expected Sunday night, with lows generally
in the teens. May see some upper single digits in the nrn
Adirondacks and far nern VT. For Monday, may see some advancing
mid-upr level clouds from west to east during the afternoon.
Otherwise, weak sfc ridge axis remains in place, and should see
high temperatures moderate into the upr 30s to lower 40s.
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 406 AM EDT Saturday...While no major storm systems are
expected through the extended period, will see large temperature
changes associated with amplified mid-upr level flow pattern
across the ern third of the CONUS and sern Canada. Polar vortex
shifts sewd from Hudson Bay across central Quebec during
Tuesday/Tuesday night. This evolution will be associated with an
arctic frontal passage across our region during the daylight
hrs Tuesday, with the potential for rain/snow showers. Early
highs on Tuesday will reach 35-40F in most locations, but
anticipate falling temps following frontal passage. By 12Z
Wednesday, 00Z GFS indicates 850mb temps of -22C to -24C. The
strong low-level CAA will result in overnight lows Tuesday night
in the single digits to lower teens, with daytime highs on
Wednesday only in the upper teens to lower 20s in most areas.
May see continued snow showers/flurries during the day Wednesday
associated with nwly flow and steep low-level lapse rates.
Wednesday night into Thursday, will begin to see a moderating trend
as sfc anticyclone builds ewd from the Great Lakes and crests over
NY/New England later Thursday. Temps moderate into the mid-upr 20s
by Thursday afternoon. South to SW return flow develops Thursday
night into Friday as sfc high pressure is expected to drift east of
New England. Should see building mid-upr level heights, with a low-
level warm front approaching from the Ohio Valley region. This will
allow for increasing clouds and the development of (mainly) rain
showers by Friday aftn/Friday night with increased isentropic ascent.
The 00Z GFS suggests we will emerge into the warm sector Saturday
with 850mb temps +6 to +8C as warm front lifts into Quebec. The 00z
ECMWF, on the other hand, stalls the E-W frontal zone across our
region with a potentially unsettled day on Saturday. Leaned toward
the more run-to-run consistent GFS at this time, with highs
approaching 50F for Saturday, but will need to monitor given larger
model differences toward next weekend.
.AVIATION /12Z Saturday THROUGH Wednesday/...
-- Changed Discussion --Through 12Z Sunday...VFR through the forecast period at all
terminals with mainly clear skies. The one exception is some
mid-level ceilings over KSLK/KRUT for a few hours after 00Z as
the clipper low passes to the south of the CWA. Winds will be
light and variable overnight before becoming southeasterly at
05-10 knots for most locations after 14Z with KMSS being the
exception, seeing northeasterly winds at 05-10 knots instead.
12Z Sunday through Wednesday...
12Z Sunday - 00Z Tuesday...VFR/high pressure overall.
00Z Tuesday - 00Z Wednesday...Possible MVFR ceilings as short
wave trough passes through the region.
00Z Wednesday - Onwards...VFR/high pressure overall.
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