Albany Office Forecast Discussion

888
FXUS61 KALY 171100
AFDALY

Area Forecast Discussion
National Weather Service Albany NY
600 AM EST Sun Dec 17 2017

.SYNOPSIS...
Below normal temperatures will continue through today moderating
to above normal early in the week. High pressure builds in for
today with fair weather. A light snowfall is possible tonight
into Monday as a warm front approaches.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 545 AM EST...A frigid airmass was in place across the
region with temperatures from 15 below zero across parts of the
western Adirondacks to the mid teens to around 20 in the mid
Hudson Valley.

For today...A ridge of high pressure will be across the region
this morning before shifting to our east this afternoon. Skies
will be mainly sunny this morning with increasing clouds from
the southwest this afternoon. It will continue to be chilly
with highs in the mid teens to around 30.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
Skies will become overcast from southwest to northeast this
evening with some light snow possible mainly after midnight.
This will be in advance of a warm front which will be tracking
from the Ohio Valley early this evening to central New York
after midnight and into eastern New York before daybreak Monday.
Lows tonight will be in the upper single digits to lower 20s.

The warm front will get hung up across the forecast area on
Monday and may even work back to the southwest as a backdoor
cold front late in the day. Expect spotty precipitation
throughout the day with the best chances for any light snow
accumulations across northern areas. Highs will be in the 30s
with some upper 20s across the northern mountains.

On Monday night the frontal boundary will lift north as a warm
front to the Canadian border by Tuesday morning. Any lingering
light precipitation will be mainly confined to the northern
mountains. Lows will be in the upper 20s to lower 30s.

For Tuesday and Tuesday night the forecast area will be mainly
in the warm sector as a cold front is not expected to drop into
northern sections of the region until after Tuesday night. Any
precipitation will continue to be light and it will be
relatively mild. Highs on Tuesday are expected to be in the mid
30s to mid 40s with lows Tuesday night in the mid 20s to lower
30s.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
The long term portion of the forecast will be dominated by an
increasingly zonal northern stream flow, although there remains at
least some potential with some southern stream moisture interaction
at times.

In the wake of a PV anomaly tracking from eastern Quebec into the
Canadian Maritimes, a surge of cold air advection and gusty winds
should occur Wednesday. There is the potential for wind gusts to
reach or exceed 40 mph at times, especially within the Mohawk River
Valley/Capital Region and Berkshires. Also, some Lake Effect
snowbands could extend into portions of the western Mohawk Valley,
with snow showers possible elsewhere. High temperatures should reach
the 20s to lower 30s across higher terrain, with 30s to near 40 in
valley areas, although these high temps may occur early in the day,
before falling in the afternoon as cold air advection strengthens.

High pressure should build across the region for Wednesday night
into Thursday. Most 00Z/17 deterministic models and ensembles track
a southern stream PV anomaly from the Gulf Coast region to the mid
Atlantic coast. This track would keep any associated precipitation
well south/east of the region, however will need to closely watch
any northward trends as we approach, as we have seen other southern
stream systems track farther north and west thus far this cold
season than initially expected. Assuming the more southern track
occurs, expect cold and dry conditions, with highs Thursday in the
20s to lower 30s, and overnight lows Wednesday night/Thu morning in
the single digits and teens.

For Thursday night-Friday, most 00Z/17 deterministic models and
ensembles track the next system developing over the southern Plains
northeast toward the Great Lakes. This may allow light precip,
mainly in the form of snow, to develop across the southern
Adirondacks and Mohawk Valley region later Thursday night, with more
widespread precipitation possible Friday, especially for areas north
of the I-90 corridor. Although there likely will be warming aloft
with this possible low track, shallow low level cold air may be
tough to dislodge across northern areas, so mixed precipitation
could occur in these areas, with a mix changing to rain farther
south. Lows Thursday night mainly in the 20s, although possibly
rising late; highs Friday potentially in the 30s for northern areas,
with some 40s possible across central and especially southern areas.

For Friday night-Saturday, as the low tracks into the eastern Great
Lakes, a cold front will approach from the west, and should move
across the region either late Friday night or during Saturday. This
may bring the greatest chances of precipitation to the region as the
system`s warm conveyor belt associated with/ahead of the cold front
moves across. There could still be some lingering low level cold air
trapped across portions of the southern Adirondacks/Mohawk Valley
region and southern VT, esp Friday evening, so some freezing rain is
possible in these areas, with plain rain expected elsewhere. Rain
showers Saturday may change to snow across higher terrain by
afternoon, as colder air moves back into the region behind the
front. Low temps Friday night may occur early, with upper 20s to mid
30s, before rising late. Saturday high temperatures may occur in the
morning, with 30s and 40s possible, before cooling in the afternoon
behind the front.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
High pressure will build across the TAF sites through this
afternoon. A warm front will then approach from the southwest
tonight and Monday.

VFR conditions are expected through at least 05Z/Mon.

For this evening, clouds will thicken with the approach of the
warm front. Some spotty light snow could develop toward 06Z/Mon
at KPOU, which may lead to MVFR Vsbys. Spotty light snow or
flurries may then expand north and east, possibly affecting the
remainder of the TAF sites between 08Z-12Z/Mon. Areas of MVFR
Vsbys will be possible during this time. In addition, Cigs are
expected to drop to MVFR levels as well between 08Z-12Z/Mon.

Outlook...

Sunday Night: Moderate Operational Impact. Chance of SN.
Monday: Moderate Operational Impact. Scattered SHRA...SHSN.
Monday Night: Low Operational Impact. Slight Chance of SHRA...SHSN.
Tuesday: Moderate Operational Impact. Chance of SHRA...SHSN.
Tuesday Night: Moderate Operational Impact. Chance of SHRA...SHSN.
Wednesday: No Operational Impact. NO SIG WX.
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: No Operational Impact. NO SIG WX.

&&

.HYDROLOGY...
No hydrologic problems are expected into early next weekend. Ice
will continue to form on areas lakes and streams.

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.
NY...None.
MA...None.
VT...None.

&&

$$
SYNOPSIS...IAA/11
NEAR TERM...11
SHORT TERM...11
LONG TERM...KL
AVIATION...KL
HYDROLOGY...IAA/11

NWS ALY Office Area Forecast Discussion