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Area forecast discussion 
National Weather Service Burlington Vermont
340 PM EDT sun Apr 20 2014

high pressure over the north country this afternoon will remain
going into Monday. A frontal system will then traverse the area
Monday night through Tuesday night. High pressure returns for
Wednesday and Thursday...followed by a low pressure system to end
off the week.


Near term /until 6 am Monday morning/...
as of 324 PM EDT Sunday...a great afternoon across the north country
will translate into a great evening and overnight as well with
high pressure intact over much of the eastern portion of the
country...with more of a shift off the East Coast by tomorrow
morning. Frontal boundary from this morning remains north of the
area across southern Quebec/ Ontario and will not affect the County Warning Area
overnight. This will provide the region with a clear to mostly
clear night with thin veil of high cloud to move through. Wind
regime for the overnight period will stay south-southwest around 5-15 miles per hour.
Biggest drop in temperatures for tonight will occur by sunset/early
evening. Large T/dew point spread over the area at this time will shrink after
loss of daytime heating. Middle 20s to low 30s in eastern Vermont/
dacks...and middle to upper 30s elsewhere will be the range of lows
for the County Warning Area.


Short term /6 am Monday morning through Tuesday night/...
as of 324 PM EDT Sunday...going into Monday morning...surface ridge
off the East Coast and remaining through the day. By Monday
night...surface low will move along the front to our north and
west. The low will begin to push into the western portion of the
County Warning Area overnight Monday...spreading precipitation into the rest of the area
by Tuesday morning. Frontal passage occurs during the day Tuesday...with a
tapering of most precipitation from west to east Tuesday night.

Cloud cover...most of the day Monday will have area mostly sunny
with transition to increasing clouds by late in the day as leading
edge of frontal clouds reach the St Lawrence Valley...and blanketing
the entire region by 12z Tuesday. With rain through the day
Tuesday...cloudy skies will persist with some slow clearing in
valley locales as winds shift to more northerly with frontal passage...putting
focus over higher terrain.

Temperatures...above normal high temperatures for entire area Monday ahead
of front...with eastern County Warning Area seeing situation of early highs with
frontal passage occurring. Overnight lows Monday will be above normal with
strong south-southwest gradient despite increasing cloud cover. Overnight
Tuesday will have area seeing at or below nounal temperatures with the
arrival of cold air advection on northerly fetch. Cloud cover will be factor in
overngt lows Tuesday. Overall highs will be in the 60s on Monday
with 50s in north New York/60s in Vermont for Tuesday with difference being front
placement. Overngt lows will range in the 30s to l40s...coldest in
hir terrain Tuesday night.

Winds...for Monday into Tuesday wind regime will remain south-southwest with
gradient tighten as front approaches. Looking for 5-15 miles per hour with
areas 10-20 miles per hour with front. With frontal passage Tuesday/Tuesday night as surface
low passes over northern zones...southerly gradient shifts to more
northerly remaining in the 10-20 miles per hour range until upper support
passes and surface high pressure builds east.

Precipitation...main p-type with frontal passage will fall as rainshowers...with some
rain shower/SW mix over higher terrain going into Tuesday night as colder air
bleeds into region. Some light snow accumulate is possible in these
spots. Overall quantitative precipitation forecast for the front will range from 0.30" to 0.60".


Long term /Wednesday through Sunday/...
as of 339 PM EDT Sunday...European model (ecmwf) and GFS models show an upper
trough will be over the region on will keep in a
chance of showers in the forecast for Wednesday. The upper trough
will move east of the region Wednesday night. A ridge of high
pressure over the Great Lakes and Ohio Valley will build slowly
east Wednesday night and will be over the north country through
early Friday with fair and dry weather expected. European model (ecmwf) and GFS
models showing a frontal system will move east from the Great
Lakes on will go with slight to low chance probability of precipitation for
showers on Friday. A closed upper low over the Great Lakes on
Friday will drift slowly east-southeast from Friday night through
Sunday ... will keep in a chance of showers from Friday night
through Sunday.


Aviation /20z Sunday through Friday/...
through 18z Monday...VFR conditions expected through the period as
a ridge of high pressure will be over Vermont and northern New York.
Satellite loop through 1730z Sunday showing middle and high clouds
streaming eastward from the Great Lakes into the region at this time.
Expecting just middle and high level clouds through the period.

Outlook 18z Monday through Friday...

18z Monday through 12z Tuesday...VFR conditions expected as a
ridge of high pressure slides off the New England coastline.

12z Tuesday through 00z Thursday...a low pressure area will move
into the region from the Great Lakes bringing rain showers and
MVFR/IFR conditions to the region.

00z Thursday through 12z Friday...VFR conditions expected as a
ridge of high pressure builds into the region.

12z Friday through 00z Saturday...a frontal system approaching
from the Great Lakes will bring a chance of showers with MVFR
conditions possible.


Btv watches/warnings/advisories...
New York...none.


near term...jn
short term...jn
long term...wgh