Scientific Forecaster Discussion
fxus61 kaly 171733
Area forecast discussion
National Weather Service Albany New York
1233 PM EST Tue Jan 17 2017
a storm system moving towards the region from the Great
Lakes will bring a wintry mix today into tonight, with the largest
impact across the higher elevations. As the storm moves away from
the area, there may be a few lingering rain or snow showers on
Wednesday, especially in the morning hours. Behind this system,
above normal temperatures will be in place for the remainder of the
week, with mainly dry conditions.
Near term /until 6 PM this evening/...
..winter weather advisories/freezing rain advisories remain in
effect across the region...
As of 1225 PM EST, precipitation was approaching from the
southwest, with its leading edge stretching from the western
Mohawk Valley through the eastern Catskills and areas just south
of the capital region...into the southern Taconics and extreme
western Litchfield Colorado.
Thus far, the precip on the leading edge is a mix of sleet/rain
with pockets of freezing rain where sfc temps are near or below
freezing. As the heavier band of precip currently to our west
moves east, we expect more precipitation to be in the form of
sleet with some snow mixing in at times. This could lead to a
quick coating of snow/sleet through 3 PM...even in areas close to
and within the capital region, with perhaps a quick coating to an
inch across higher elevations, and north into Saratoga co.
Temps have risen into the mid 30s across northern areas from the
eastern Adirondacks into the Lake George/Saratoga region and
southern VT, as a period of sunshine occurred this morning.
However, dry low level air remains in place in these areas, as
evidenced by dewpoints in the upper teens to lower 20s, so expect
temps to fall at least 2-3 degrees within two hours of precip
onset due to wet bulb effects.
Areas further south, temps are generally in the lower to mid 30s,
slightly cooler due to more persistent and thicker cloud cover.
Again, dewpoints remain in the lower/mid 20s, so wet bulb effects,
and cold ground will lead to areas of icing once any liquid
Precipitation will become steadier and more widespread during the
afternoon hours, and most of the area will be seeing some type of
precipitation by the mid afternoon or so. P-type will continue to
be variable, although areas north of the Mohawk Valley and
Interstate 90 will have the better chance of seeing snow or sleet,
with rain or rain mixed with sleet further south (perhaps freezing
rain in higher elevations areas that are still below freezing).
Temps look to warm up into the 30s today, although will likely
rise or fall at times depending on precip intensity. Best chance
of staying closer to freezing will be across higher elevations and
northern/northeastern parts of the region.
Short term /6 PM this evening through Wednesday night/...
low pressure will continue to lift towards western New York this
evening. At the same time, another area of low pressure be forming
along the storm's triple point over New Jersey and will be
strengthening as it heads east to northeast along the eastern
Precipitation will continue for this evening into tonight. The
combination of a light northerly flow and some cooling aloft
thanks to the approaching upper level trough will continue to
allow for plenty of snow and sleet across northern areas
overnight. Further south (basically I-90 on southward), valley
areas will see a mix of rain and sleet, with freezing rain across
the higher elevations. Some snow may even occasionally mix in at
times for the capital region into the Berkshires depending on
precip intensity, but primarily looks like messy mix of
rain/sleet. Best chance for seeing snowfall will be across
southern Vermont and far northern Berkshires, where the cold air
looks to be the deepest.
Steady precip will be tapering off towards daybreak Wednesday. By
this time, several inches of snowfall looks to occur across
northern areas (adirondacks, southern greens), with perhaps as
much as 6 inches across southern Vermont. Elsewhere, a light coating of
snow/sleet and ice looks to occur, although high terrain areas
(such as the helderbergs, Taconics, Berkshires, Litchfield hills)
may see up to a quarter of an inch of ice. There will likely be
large differences in snow/ice accumulation over short distances
due to elevation and precip coverage. Overnight temps look to
remain fairly steady in the lower to middle 30s across the area.
Although the storm's occluded front will pass early in the day, with
the upper trough moving across the area, cyclonic flow will allow
for some lingering rain or snow showers into the day Wednesday.
Best chance of seeing snow will be across the higher elevations.
Outside of this precip, still could be some pockets of drizzle at
times. Any additional snow accumulation on Wednesday looks
minimal. Temps will mainly be in the 30s, with temps rising above
freezing over the majority of the region.
With the shortwave moving away, precip should be ending for most
locations on Wednesday night, but it will continue to remain
fairly cloudy. Overnight temps will only fall a few degrees, with
lows in the upper 20s to mid 30s. However, with temps falling
below freezing, any wet surfaces may freeze over, so some black
ice will be possible for any untreated surfaces.
Long term /Thursday through Monday/...
as mentioned in the previous afd, complex pattern remains in place
per the 00z global model consensus. The idea favors an increasing
ridge over the eastern Continental U.S. With trough over the center of the
nation. Eventually, this aforementioned trough amplifies enough
with a strengthening storm that may impact our region toward the end
of the long term forecast period.
We begin this long term with the approach and passage of a weakening
frontal boundary. Now, each model differs with timing and placement
of this front but they all agree moisture profiles will be lacking.
So we will leave in a slight chance pops for the northern half of
the County Warning Area. Otherwise mainly dry with mainly 30s and lower half of the
40s for valley locations.
Friday and into the weekend, seems the ridge may evolve and hold off
the approach of the upper low currently situated over The Four-
Corners region. The European model (ecmwf) has come more in line with the global
model consensus with a weakening trend of the approach of this wave
as ridge builds. So slight chance mainly southern areas Friday into
Then the ridge becomes increasingly dominant heading into the
weekend as thermal column moderates further with above 0c h850
temperatures. While there could be lots of clouds around, breaks of
sunshine should allow for highs well into the 30s and low-mid 40s
with lows generally between 25-35f.
Potent wave and strong Pacific jet comes ashore and develops a
deepening trough and surface cyclone over the center of the nation
later Sunday. This storm is progged by both the European model (ecmwf)/GFS/ggem to
tap into deep moisture from both the Gulf of Mexico and Atlantic
heading into Monday as this storm lifts east-northeast. As this system becomes
negatively tilted, that moisture will assist with a prolonged mainly
rain event for next Monday per latest thermal profiles.
Temperatures through the period should average above normal with
below normal precipitation until Monday.
Aviation /18z Tuesday through Sunday/...
conditions will deteriorate rapidly this afternoon at the taf
sites as precipitation moves in from the the southwest. Conditions
will become mainly MVFR by late afternoon. Precipitation types
will vary as wet bulb process will likely start as a wintry mix at
all taf locations. Warmer air should allow for mainly rain at kpou
for the majority of the event with northern locations likely
sticking with a mix for the balance of the afternoon hours. This
is when the high potential for MVFR conditions will occur. These
conditions are expected to persist after sunset with IFR
conditions occurring overnight.
The precipitation will taper off late tonight with mainly MVFR
conditions occurring Wednesday morning.
Winds will be east-southeast at speeds less than 10 kts through
the overnight hours and then become east northeast at less than 5
kts Wednesday morning.
Wednesday night: low operational impact. Slight chance of rain showers...shsn.
Thursday: low operational impact. Slight chance of rain showers...shsn.
Thursday night: no operational impact. No sig weather.
Friday: no operational impact. No sig weather.
Friday night: no operational impact. No sig weather.
Saturday: no operational impact. No sig weather.
Saturday night: no operational impact. No sig weather.
Sunday: no operational impact. No sig weather.
a storm system will bring a wintry mix to the region today into
tomorrow. Total liquid equivalent amounts will be one half inch
to one inch. Although some of this precipitation will be frozen,
some minor rises on rivers and streams can be expected, especially
from the Mohawk River on southward. However, no flooding is
Behind this storm system, temperatures will average above normal
for the remainder of the week. Some snow melt over the Adirondacks
and southern Vermont may contribute to some additional runoff,
but any rises on rivers and streams will only be very minor and
overnight lows should fall below freezing most of the time.
Little, if any, precipitation is expected for Thursday into the
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
CT...Winter Weather Advisory until 7 am EST Wednesday for ctz001-
New York...Freezing Rain Advisory until 7 am EST Wednesday for nyz038-040-
Winter Weather Advisory until 7 am EST Wednesday for nyz032-
Massachusetts...Winter Weather Advisory until 7 am EST Wednesday for maz001-
Vermont...Winter Weather Advisory until 7 am EST Wednesday for