Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Albany New York
620 am EST sun Nov 23 2014
a weak upper level disturbance and warm front will move
north and east of the region today...ending the rain...and allowing
for slightly milder temperatures. A stronger warm front will push
northward across the region late tonight and early Monday...bringing
widespread rain. It will be followed by very mild weather for Monday
afternoon. A cold front will pass through the northeast Monday
night...with a return to seasonable temperatures by Tuesday.
Near term /until 6 PM this evening/...
as of 615 am EST...rain showers continue to decrease in areal
coverage from west to east...with mainly just isolated/scattered
coverage at best. This decreasing trend should continue over the
next 2 hours. Some patchy drizzle/fog could form in some areas
We expect clouds to linger across northern areas through at least
midday...if not well into the afternoon across portions of the
southern Adirondacks. Further S and east...we expect some breaks in
the clouds to develop through middle morning...with a few periods of
partly to mostly sunny skies possible this afternoon...with the
least clouds expected across the middle Hudson Valley and northwest CT.
A tricky call on maximum temperatures today...as clouds and a cold ground may
limit the warmth for areas north of Interstate 90...while southern
areas could potentially rise fairly quickly this afternoon. Have
generally sided with the slightly cooler mav MOS across northern
areas...and toward the warmer met MOS for southern areas. This
results in maximum temperatures reaching the Lower/Middle 40s for northern
areas...45-50 for most central areas...and 50-55 across southern
areas...warmest in lower elevations. However...should sunshine
break out earlier and more abundantly than currently
expected...even warmer maximum temperatures could occur.
Short term /6 PM this evening through Tuesday/...
tonight...a potent upper level disturbance currently traversing
the Gulf Coast/lower MS valley region...is poised to track rapidly
northeastward tonight...in a somewhat weakening form as a deeper
upper level trough carves out in the plains. As this feature
approaches...some weak and transient middle/upper level ridging is
expected to pass across the region this evening...possibly
allowing for some breaks in the clouds. Depending on how much
clearing can occur...temperatures could fall off shortly after
sunset...into the Lower/Middle 30s in many areas...before rising
after midnight as the clouds thicken. Rain should then quickly
overspread the region from south to north between midnight and 3
am...with a fairly soaking rainfall expected through daybreak. A
strong low level jet...forecast to reach 60-70 knots at and above
h850...will also translate northward across the region. A very
stable boundary layer should prevent most of this from mixing
down...however...across higher terrain of the
Taconics...Berkshires...and southern Green Mountains may experience an
increase in winds as it passes...with some gusts possibly reaching
35-45 miles per hour at times toward daybreak.
Monday...some lingering rain and/or showers will be possible
through around 10 am as the aforementioned impulse...and surface warm
front move through. Thereafter...it appears there should be little
in the way of upper level forcing to focus much precipitation.
Will therefore decrease probability of precipitation into the slight chance to low chance
range for the afternoon...highest across the Adirondacks which
will be closer to lingering upper level forcing and added
low level orographic effects...for isolated to scattered showers.
Low clouds may occasionally break...especially across the middle Hudson
Valley region. It should be quite warm...with temperatures reaching the
Lower/Middle 60s for most lower elevations from Albany south and
east...and 55-60 to the north and west. However...again...should any more
prolonged breaks in the clouds develop...even warmer maximum temperatures
Monday nt-Tue...a cold front will move across the region Monday night.
Most of the upper level forcing is poised to pass north and west of the
region. In addition...low level convergence appears to weaken as
the front passes through...as a general southwest flow prevails on
either side of the boundary. Therefore...will only indicate chance
probability of precipitation for Monday nt as the front passes for showers...tapering off
later at night. Some lake/orographic effect showers of rain and
snow may develop toward daybreak Tuesday across the western
Adirondacks. These showers may then continue through much of Tuesday.
Elsewhere...expect some clearing to occur in most areas Tuesday
morning...before clouds begin to develop/expand S and east into areas
mainly north and west of Albany in the afternoon as cold air advection
intensifies. As for temperatures...expect mins to fall into the 30s to
lower 40s by daybreak Tuesday...and then reach 45-50 in most valley
areas...and 40-45 across higher terrain for Tuesday afternoon.
Long term /Tuesday night through Saturday/...
the long term period looks to be active during the first half and
relatively dry during the second half. There still exists
considerable disagreement amongst the models with regards to the
coastal system midweek. The middle of the week including the
Thanksgiving Holiday makes for a tricky forecast. The European model (ecmwf) has
continues to maintain its track and intensity as it lifts a coastal
low (miller type a) across the eastern tip of Long Island. The European model (ecmwf)
also has extreme fgen at 700 mb which oscillates across forecast area as we go
forward in time from 12z Wednesday through 12z Thursday. It has the low
getting captured by the upper trough thus keeping the low hugging
the coast as it moves northeast from the eastern tip of Long Island
at 06z Thursday to downeast Maine by 12z Thursday. The European model (ecmwf) has
been very consistent for the last 5 model runs with this track.
Meanwhile the GFS and ggem keep the system well offshore with the
ggem farthest south and east at 06z Thursday and the GFS farthest
north and east. At this point it is best to maintain continuity with
previous forecasts and call for chance to high chance probability of precipitation from the
period from Wednesday into Thursday. Will continue with mention of
storm and uncertainty in severe weather potential statement. In addition GFS and ggem have a much
weaker system with central pressure of low at 12z Thursday 982 mb on
European model (ecmwf)...997 mb on GFS and 1007 mb on ggem.
Mainly dry weather is expected after the passage of the storm except
for a clipper type system potentially impacting the northern portion
of the forecast area on Saturday.
As for temperatures during the long term period...a cool down is in store
with temperatures falling to well below normal once again by the end of the
long term period. Highs on Wednesday and Thursday are expected to
be in the 30s to around 40 with middle 20s to middle 30s on Friday and
Saturday. Lows will range from the middle 20s to lower 30s Tuesday
night and Wednesday night...the upper teens to middle 20s Thursday
night and the middle teens to lower 20s on Friday night.
Aviation /11z Sunday through Thursday/...
high pressure will build back into our region from the south and
east this afternoon.
Mainly VFR conditions are expected at the taf sites through this
evening...this will then be followed by MVFR conditions developing
between 05z and 08z as an area of rain lifts northeast ahead of a
warm front lifting northeast from the Ohio Valley and western
Expect southerly winds of 5-10 kts today through the afternoon with
light winds from the south or southeast tonight.
Monday night: moderate operational impact.Breezy chance of rain showers.
Tuesday: low operational impact.Breezy no sig weather.
Tuesday night: no operational impact. No sig weather.
Wednesday: moderate operational impact. Chance of rain...sn.
Wednesday night: moderate operational impact. Chance of snow.
Thanksgiving day: moderate operational impact. Chance of rain showers...shsn.
no significant hydrologic problems are expected over the next
A widespread precipitation event...this time in the form of liquid
rainfall...will impact the region tonight into early Monday.
Rainfall amounts will generally be around a half inch or
so...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 more precipitation to the region
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