Area Forecast Discussion
Issued by NWS Burlington, VT-- Remove Highlighting --
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FXUS61 KBTV 210749
Area Forecast Discussion
National Weather Service Burlington VT
349 AM EDT Fri Apr 21 2017
A low pressure area and a warm front will approach the North
Country overnight and will bring moderate rain to the region,
mainly during the pre-dawn hours. Rain will continue into
Friday, before tapering off to showers Friday afternoon and
Friday night. A ridge of high pressure will build into the
region Sunday and will remain over the North Country through
early next week.
.NEAR TERM /UNTIL 2 PM THIS AFTERNOON/...
As of 1123 PM EDT Thursday...Forecast remains on track. Broad
region of 850-700mb warm advection across sern Ontario into
central NY will shift newd into nrn NY and VT during the
remainder of the overnight hrs...in advance of low pressure
across nrn lower Michigan. It appears convective instability
driving tstm activity across s-central NY and PA will remain
south of our region. However, strong synoptic ascent will move
across the North Country between 06-09Z, bringing steady
moderate rainfall to most locations for several hrs. Only minor
adjustments to total QPF...generally 0.5-0.75" expected, but
orographic enhancement is possible on S-SW facing slopes, with
rainfall near 1" possible srn Greens and portions of the
Adirondacks high peaks.
Winds are light and variable late this evening. However, will
see some gusty S-SE winds around daybreak with increasing
p-gradient, with gusts 20-30 mph once the steady rain ends, and
gusts locally to 30-40 mph along the immediate wrn slopes of
the Green Mtns with downslope effects.
Rain will continue into Friday morning before tapering off to
showers Friday afternoon as best synoptic forcing shifts to our
east. A slight chance of showers will continue into Friday
night. Expecting low temperatures to be mainly in the 40s
overnight. High on Friday from the upper 40s to lower 50s. Lows
Friday night from the upper 30s to lower 40s.
.SHORT TERM /2 PM THIS AFTERNOON THROUGH SUNDAY/...
-- Changed Discussion --As of 349 AM EDT Friday...High pressure will build steadily
into the region Saturday night with any scattered evening
showers ending across northeastern counties overnight. Lingering
moisture trapped beneath a building synoptic inversion should
keep ample cloud cover across the area early before skies trend
partly cloudy overnight. If enough clearing develops late patchy
fog may develop in a few areas. Lows a blend of available
guidance offering values mainly in the 30s.
A better day then on tap for Sunday as elongated high pressure
bridges east from the Ohio Valley and Great Lakes into the
northeast. Expect partial to full sunshine through the course of the
day with light winds and sesaonably mild temperatures in the upper
50s to lower 60s. Should be a great day for any outdoor
-- End Changed Discussion --
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
-- Changed Discussion --As of 349 AM EDT Friday...Mainly fair and dry weather is then
expected for Sunday night into Monday as high pressure generally
remains in control. A weak front will attempt to drop southward
into the northern tier of counties Sunday night with perhaps an
outside shot of a few showers from the international border
northward, but all and all this feature will be a non-player
other than bringing in a few more clouds as deeper moisture will
be limited. Thermal profiles suggest little airmass change into
Monday, perhaps a few degrees cooler across the north as highs
top out in the 50s to around 60.
More uncertainty then creeps back into the forecast from Tuesday
onward into Thursday of next week. Latest medium range guidance
remains at odds in regard to vigorous close energy lifting northeast
from the souteastern seaboard by Monday night into Tuesday with the
GFS/Canadian GEM having a more westerly solution than the ECWMF, and
particularly the UKMET which keeps a much slower system down across
the SC/NC region until Wednesday night. Given these differences a
middle of the road path will be offered until more clarity can be
achieved. This will suggest mainly dry weather will continue Monday
night before a gradual increase in shower chances arrive into
southern counties by Tuesday afternoon and across the remainder of
the area Tuesday night.
Thereafter, I`ll maintain a general 20-30 percent chance of showers
from Wednesday onward into Thursday as another northern stream
surface front drops into the region and waffles near or just
northwest of us. Hard to really pinpoint the degree or areal
coverage of any showers related to this feature at this point, but I
imagine there will be considerable stretches of drier weather in the
this time frame. Temperatures will gradually trend milder, with
widespread 60s expected from Tuesday onward into late week.
-- End Changed Discussion --
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
Through 06Z Saturday...Conditions will largely be a mix of VFR
and MVFR over the next 24 hours with steady rainfall through
about 12-15Z reducing vsby to MVFR and cigs a mix of VFR/MVFR.
Thereafter scattered showers may briefly reduce vsby at times,
but cigs should lift to VFR area-wide until later in the evening
after 22-24Z when a gradual lowering back to MVFR is expected.
Winds mainly SSE becoming increasingly gusty by dawn with gusts
in the 20-30kt range especially at KBTV through the daylight
hours, abating after sunset.
Saturday: VFR/MVFR. Slight Chance SHRA.
Saturday Night: VFR/MVFR. NO SIG WX.
Sunday: VFR. NO SIG WX.
Sunday Night: VFR. Slight Chance SHRA.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. NO SIG WX.
As of 401 PM EDT Thursday...No major issues are expected on
area rivers and streams but we should see some modest rises on
Friday with basin average QPF in the 0.50-0.90" range (occurring
late tonight into Friday AM). Concerns still exist on Lake
Champlain with gusty southerly winds developing late tonight and
Friday morning. This will likely cause rises across the
northern portion of Lake Champlain, where Rouses Point could
rise slightly above flood stage on Friday. This will be closely
monitored over the next 12-24 hours.