Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Albany New York
1254 PM EST Monday Nov 24 2014

Synopsis...
a strong warm front will move north from the middle Atlantic region
and Ohio Valley this morning...bringing a widespread rainfall to
our area. It will be followed by very mild weather for this
afternoon. A cold front will pass through the northeast
tonight...with a return to seasonable temperatures by Tuesday. A
coastal storm is expected to impact the region during the middle
of the upcoming week with the potential for heavy snowfall.

&&

Near term /until 6 PM this evening/...
record high temperatures expected across much of region this
afternoon. Wind Advisory has been cancelled for this afternoon.

As of 1250 PM EST...the warm front continues to lift northward
across the region with most of the region dry after the early
morning showers. The only exception will be across portions of the
Berkshires and southern Vermont...where some patchy drizzle will
be possible the next few hours. Most areas will see at least some
sunshine this afternoon...with partly sunny skies expected.

The two big playmakers through this evening will be gusty
south/southwest winds and record warm high temperatures for this
date. Expecting gusty winds this afternoon into this
evening...especially across the higher terrain with gusts of 30-40
miles per hour occasionally at times...short of advisory criteria.

This sunshine coupled with warm air advection...has allowed
temperatures to soar well into the 60s across much of the region.
Have raised high temperatures across the region by several degrees
and am now forecasting record high temperatures in spots...with
portions of the Hudson Valley expected to reach into the low 70s.

The record high at Albany is 69 degrees set back in 1979...with a
high temperature now expected of 71. The record high at
Poughkeepsie is 68 degrees set also back in 1979 with a high
temperature now expected to reach into the low 70s.

&&

Short term /6 PM this evening through Tuesday night/...
for tonight a cold front will cross the region late this evening
bringing a return to more seasonable air. There will be some
widely scattered to scattered lake effect rain and then snow
showers across the western Adirondacks. Lows tonight will be in
the middle 30s to middle 40s.

On Tuesday...the forecast area will be mainly dry except for some lingering
lake effect rain and snow showers across the western Adirondacks
and western Mohawk Valley. A weak ridge of high pressure will be in
place across much of the forecast area and temperatures will be noticeably cooler
than Monday. Expect highs on Tuesday to range from the upper 30s
northwest to middle 50s southeast.

On Tuesday night...clouds will start to increase overnight ahead
of our coastal storm. While it is expected to be dry...it will be
much cooler than recent nights with lows in the middle 20s to lower 30s.

&&

Long term /Wednesday through Monday/...
Winter Storm Watch now in effect for much of eastern New York and
adjacent western New England for Wednesday morning into Thursday morning...

Confidence continues to increase that a significant winter storm
will impact much of eastern New York and western New England during the
Wednesday-Thursday time period. Latest 00z/24 numerical sources of guidance
continue to suggest a Miller-a type storm system tracks northward
along the East Coast Wednesday into Wednesday nt...reaching the New England
coast by Thursday morning.

The 00z/24 European model (ecmwf) remains most consistent with its previous
cycles...albeit perhaps just a bit farther east than the 12z/23
cycle...which was so far west it might have brought some mixed
precipitation to at least portions of western New England. The
00z/24 GFS remains farther S and east with the track...but still allows
for significant precipitation...mainly snow...to affect areas from
Albany and points S and east. Even the 00z/24 Gem has trended farther north
and west...although still remains the least aggressive with overall
precipitation.

The 00z/24 gefs remain fairly similar to previous cycles...with one
robust member implying well over an inch of liquid equivalent quantitative precipitation forecast
all in the form of snow...and several others with liquid equivalent
quantitative precipitation forecast in the 0.3-0.6 range...as snow.

Given that this week will be such an active travel week due to the
Holiday...and increasing overall confidence...we have issued the
Winter Storm Watch for most of eastern New York state and western New
England...where the snow potential for 7 inches/12 hours...or 9
inches/24 hours is highest.

One of the significant players in the storm...a pv anomaly currently
digging south across the northern rockies...is becoming better
sampled by upper air observations. The second major player...energy
just coming ashore in western Canada...will become better sampled
today and tonight. So...hopefully model solutions will become more
tightly clustered later today or night. But at the very
least...there is some potential for locally heavy snow within the
watch area...with additional refinements in details...amts...and
timing forthcoming.

Based on current guidance...it appears that snow should overspread
much of the region from south to north rather quickly during
Wednesday morning...with periods of moderate to heavy snow for Wednesday
afternoon and night. Again...timing could be adjusted somewhat with
newer sources of guidance...so stay tuned. Snow should gradually
taper off during Thursday morning.

Some additional questions to Ponder are...how cold the boundary
layer will be initially before dynamical and wet bulb cooling occur
to allow for all snow. It is possible that some areas could start
out as a rain/snow mix...and reduce overall accums.

Also...depending on how far north and west warmer middle level air
advects...there could be some mixed precipitation at some
point...especially across portions of western New England and the middle
Hudson Valley.

In the wake of the storm system...cold and windy conditions with
some snow showers/flurries will be possible Thursday afternoon into
Friday. A fast moving clipper type system could bring some snow
showers for Friday...then again late Sat into sun.

Temperatures should generally remain below normal through the period...with
maximum temperatures ranging from the 30s in lower elevations...and 20s to
lower 30s across higher terrain. Overnight lows should fall into the
teens and 20s...although some colder min temperatures could occur in areas
where winds decrease.

&&

Aviation /18z Monday through Saturday/...
as of noon...the warm front has moved north of all of taf sites.
There is unlikely to be any more IFR (except maybe briefly) but
occasionally we have low MVFR ceilings (extra fuel required) at all
the taf sites except kpou through 22z.

VFR ceilings should prevail through evening peak as slightly drier air
mixes downward.

Then...a cold front will cross the tafs around 06z...bringing
perhaps another shower (vcsh) and a wind shift from S to west-southwest.

The surface winds will remain gusty from the south to southwest
this afternoon...gusting up to 25kts...mainly at kalb and kpsf.
The wind will relax a little heading into dark...but then pick up
again toward midnight with arrival of the cold front. Gusts at
that time will be back around 20kts.

VFR conditions will prevail Tuesday...but by Wednesday there is a
good chance of some snow or mixed precipitation at all the taf
sites so a high operational impact is expected along with IFR
conditions. Right now...the timing would indicate the
precipitation might hold off for the morning peak
Wednesday...moving in by midday Wednesday.

Outlook...

Tuesday night: no operational impact. No sig weather.
Wednesday: high operational impact. Likely snow.
Wednesday night: high operational impact. Likely snow.
Thanksgiving day: moderate operational impact. Chance of shsn.
Thursday night: no operational impact. No sig weather.
Friday: no operational impact. No sig weather.

&&

Hydrology...
no significant hydrologic problems are expected over the next
several days. The only location which may get close to flood stage
due to rainfall and snowmelt is ddmn6 (delta dam).

A widespread precipitation event...this time in the form of liquid
rainfall...will impact the region through this morning. Rainfall
amounts will generally be around a half inch to three quarters of
an inch...but locally higher across the southeast Catskills/middle Hudson
Valley and northwest CT. This may allow for some minor rises on rivers
and streams...but no flooding is anticipated. Behind this rain
event...cooler and drier air will move back into the region for
Tuesday. A storm system may bring significant snow to the region
for the midweek period.

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...Winter Storm Watch from Wednesday morning through Thursday
morning for ctz001-013.
New York...Winter Storm Watch from Wednesday morning through Thursday
morning for nyz039>043-047>054-058>061-063>066-082>084.
Massachusetts...Winter Storm Watch from Wednesday morning through Thursday
morning for maz001-025.
Vermont...Winter Storm Watch from Wednesday morning through Thursday
morning for vtz013>015.

&&

$$
Synopsis...irl/11
near term...irl
short term...11
long term...kl
aviation...hwjiv
hydrology...11

National Weather Service Glossary of Abbreviations