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Area forecast discussion 
National Weather Service Albany New York
937 am EDT Monday Mar 30 2015

Synopsis...
a cold front will whip across the region this afternoon bringing
rain and snow showers. There will also be some gusty winds as well.
High pressure briefly builds in tonight...but a disturbance will
bring more clouds and perhaps a little more precipitation to mainly
areas south of Interstate 90 on Tuesday. High pressure is forecast
to bring fair weather on Wednesday.

&&

Near term /until 6 PM this evening/...
as of 937 am...approaching cold front has pushed through Buffalo
but is not yet to Syracuse. Ahead of the front there are bands of
snow and temperatures are in the low to middle 30s. Latest hrrr shows
front should reach the Hudson River between 2-3 PM and pass east
of our western New England counties by 5 PM.

This front will turn the winds to a westerly direction. A second
front will cross the area this evening and turn the winds more
northwesterly...and bring in another surge of cold air.

Current update was to time bands of showers moving across the area
today. No change made to maximum temperatures. Maximum temperatures today may be
to high over the Adirondacks...where temperatures may not make it
above freezing. Elsewhere...they look on track with highs in the
30s terrain to 40s to near 50 in the middle Hudson Valley.

Winds still expected to be quite gusty this afternoon after the
first front passes. Winds currently over western New York are
gusting in the 25-35 knot range from the west.

Skies are now cloudy across the area. Expect a few breaks this
afternoon...especially easy of the high terrain as westerly winds
downslope into the valleys.

&&

Short term /6 PM this evening through Wednesday night/...
tonight high pressure will briefly build in resulting in a clearing
sky and a gradual diminishing wind (after some gusty winds in the
evening)...but probably not go completely calm. Night time lows will
generally be in the 20s...except upper teens across the Adirondacks.

A trailing piece of northern stream upper energy tracks southeast
out of the Great Lakes Tuesday and tracks off the Middle Atlantic
States Tuesday...with the northern edge of a precipitation
shield...possibly extending just south of I-90. Clouds will extend
northward through the entire County Warning Area. While on paper it looks cold
enough for this precipitation to be snow...that fact that it is
nearly April...the air mass will not be all that cold...and much of
the precipitation will fall during the day allowing solar influence
through the clouds...ptype will be a challenge. If the precipitation
is light enough (which we believe will be the case) we would
probably be looking at snow at elevations higher than 1500
feet...and rain or rain snow mix in the valley with very little if
any accumulation. Even over the higher terrain accumulations (if
any) look light but again we will have to monitor later trends to
see if there signals ramping up the quantitative precipitation forecast (which would favor more snow
over rain and of course more accumulation). We kept probability of precipitation in the
chance category for now...even though some guidance indicates
higher chances than that to our south.

Project high temperatures look to be 40-45 in the valleys (possibly
highest north of Albany where the clouds will be the thinnest). High
temperatures will be in the 30s over the higher terrain. Again...if
precipitation turns out to be heavier...these highs would have to be
lowered several degrees.

The disturbance will move on Tuesday evening...leaving high pressure
to build back in. The sky should clear and with light wind
temperatures Will Tank (especially in any areas that pick up even
fresh coating of snow). Lows will dip back into the lower to middle 20s
Albany southward...15-20 further north and west.

Wednesday looks like a fairly decent day (at least by this Spring
standards). Bright sunshine will bolster temperatures back into the
lower to middle 40s in the valleys...middle to upper 30s higher terrain.
These values are still a bit below normal for this time of year.

&&

Long term /Thursday through Sunday/...
considerable uncertainty in the long term portion of the
forecast...especially regarding the handling of fast moving
Pacific shortwave energy during the Friday-Sat time period.

The overall pattern will be deamplifying at the start of the
extended across the u... the persistent polar vortex relaxes and
reorients a bit further north and west across Canada. This will allow for
fast moving Pacific systems to track across the central and eastern
U.S. Ridging ahead of one of these disturbances should bring a
period of milder temperatures for Thu-Fri...before temperatures trend back
to below normal by next weekend as middle/upper level heights once
again fall across eastern Canada and the Great Lakes region.

Thursday-Sat nt...a pair of upper level impulses will track east from
the western U.S. During this time period...with a northern piece
tracking into central Canada...while a southern one tracks into
the Southern Plains. Frontal systems associated with the northern
one should impact our region Thursday...with a warm front
initially...then a cold front sometime Thursday nt or Friday. This should
bring rain showers to the region Thursday afternoon-early Friday. Then...as
the southern piece of energy tracks into the Southern Plains and
eventually the eastern u... wave of low pressure may develop
along the cold front...and allow precipitation to linger/redevelop
later Friday and possibly into Sat. Depending on how the upper level
energy and timing of associated surface boundaries track Friday-
Sat...there could be enough cold air for p-type issues with any
lingering precipitation Friday night. In addition...some guidance
suggests that any southern pieces of energy and waves of low
pressure track further south with less impacts on our region.
So...at this time...generally have indicated only chance probability of precipitation for
this time period...mainly for rain showers...although some snow
could occur Friday nt into Sat morning depending on the exact timing
and track of systems.

Sun...a return to below...to potentially well below normal temperatures is
quite possible in the wake of any previous system. It should be
generally dry...although can not rule out some showers of snow or
rain depending on instability and overall progression of upper level
energy.

Temperature wise...highs Thursday will be in the upper 40s and
50s. Lows Thursday night in the middle 30s to middle 40s. Highs Friday
generally in the 50s to lower 60s...with upper 40s over the
Adirondacks. Lows Friday night as colder air moves in will be in
the upper 20s and 30s. Highs Saturday in the upper 30s and 40s.
Lows Saturday night in the middle teens to the 20s. Highs Sunday in
the middle 30s to middle 40s.



&&

Aviation /13z Monday through Friday/...
as of 630 am...the initial band of scattered snow showers
associated with a warm front was already moving through the taf
sites and will likely be east of the region by 12z (the start of
the taf period). Even after the warm front moves through...the
threat of showers (mainly rain showers later in the day...will
continue ahead of a cold front that will cross the region during
the middle afternoon period. Behind the cold front there will still
be a chance of showers as an upper level disturbance also affects
the region.

Although there will be a few weather features affecting the region
during the taf period ending at 12z Tuesday...moisture is limited
and forcing is relatively weak...so for the kgfl/kalb/kpou/kpsf
taf sites have generally forecast VFR conditions for most of the
taf period. The exception is at kgfl...where a tempo group for
MVFR ceilings/visibilities due to snow showers has been forecast between 12z
and 15z. Otherwise...the threat of showers is low and timing
difficult...so have only indicated vcsh during the day at the
other taf sites and during other times of the tafs.

Surface winds will be southerly ahead of the warm front at 8 to 12
kts with gusts of 15 to 20 kts. After the warm front the winds
will shift to southwesterly and increase to 10 to 15 kts with
gusts of 18 to 25 kts during middle/late Monday morning. By middle
afternoon the winds will shift to westerly after the cold front
moves through with speeds of 12 to 18 kts and gusts of 20 to 30
kts. After 00z Tuesday...the speeds will begin to slowly
diminish...dropping to 5 to 10 kts by late tonight...with some
gusts to 15 kts.

Outlook...

Tuesday: low operational impact. Slight chance of rain showers.
Tuesday night: low operational impact. Slight chance of snow.
Wednesday and Wednesday night: no operational impact. No sig weather.
Thursday and friday: low operational impact. Chance of rain showers.

&&

Fire weather...
gusty winds up to 40 miles per hour today...

A fast moving clipper will some snow showers mainly north and
west of the capital region early Monday...with mostly rain showers
from Albany south and east. A cold front could bring a few more
showers Monday afternoon. High pressure will build back
in tonight. Another clipper tracking mainly south of the region
could bring light rain or snow to southern areas Tuesday.
High pressure builds into the region Wednesday.

Relative humidity values will range between 30 and 55 percent Monday and Tuesday
afternoon. Relative humidity values will range between 70 and 100 percent tonight
and Monday night.

A south wind average 10 to 20 miles per hour...then become west to
northwest by with gusts to 40 miles per hour by afternoon. The wind will
diminishing down 5-15 miles per hour late Monday night...light and variable
Tuesday.



&&

Hydrology...
no Hydro related problems are anticipated through at least
Wednesday.

Well above normal temperatures are possible on Thursday which
would bring about widespread snow melt. A large storm system may
impact the region Friday into Saturday with moderate amounts of
rain...which would lead to significant river rises.

For details on specific area rivers and lakes...including observed
and forecast river stages and lake elevations...please visit the
advanced hydrologic prediction service /ahps/ graphs on our
website.



&&

Aly watches/warnings/advisories...
CT...none.
New York...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...snd/hwjiv
near term...sand
short term...snd/hwjiv
long term...kl/gjm
aviation...gjm
fire weather...hwjiv/NAS
hydrology...sand

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