Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Albany New York
717 am EDT Thursday Oct 2 2014
clouds will eventually break for sunshine today as an upper level
storm south of New England continues to move eastward and away
from the region. Dry and warm conditions are expected on
Friday...before a cold front brings gusty rain showers and cooler
temperatures to the region for the weekend.
Near term /until 6 PM this evening/...
as of 632 am EDT...an upper level low is situated just southeast
of eastern New England. This system is moving away...but before it
does...it is pulling moisture off the Atlantic Ocean and producing
showers across parts of Massachusetts and Connecticut. With these
showers wrapping around the upper level low within the broad
easterly flow aloft...they are tracking into parts of southern Vermont...the
Berkshires...and Litchfield Hills this morning. While showers have
mainly diminished over our area...we cannot rule out a light rain
shower or sprinkle across western New England through the middle
morning hours. The latest 08z 3km hrrr shows any activity after
this time remaining well east of our area.
In addition to the rain showers is plenty of low clouds /stratus/
and some patches of fog. With a low level inversion in place
today...it will take a while for this low level moisture to become
mixed out. As a result...we can expect mostly cloudy skies through
much of the day...with clouds eventually breaking for increasing
amounts of sun during the afternoon. The exception will be across the
western Mohawk Valley and western Adirondacks...where the clouds
currently aren/T as thick...and more sun can be expected this
Maximum temperatures today will range from the low 60s to low 70s...with the
warmest across western areas. Temperatures in the capital region/Hudson
Valley look to top out in the upper 60s.
Short term /6 PM this evening through Saturday night/...
a brief area of upper level ridging will build into the area for
tonight into Friday. This will allow for continued clearing skies
overnight...although some patchy fog will develop thanks to the
good radiational cooling conditions. Min temperatures tonight will mainly be
in the 40s to near 50. Partly to mostly sunny skies are expected
on Friday...with the most clouds across the Adirondacks. With 850
hpa temperatures around 10 to 11 degrees c...above normal temperatures can be
expected...with highs in the middle 60s to middle 70s across the area.
A strong cold front will be moving towards the area for Friday
night into Saturday. Most of the Friday night should be dry...although
western areas will start to see some showers by later in the
night. Min temperatures Friday night will be in the 50s.
This front will be accompanied by a deepening trough that will
take on a negative tilt for Saturday. Ahead of this front...a
strong low level jet of 50 knots /about 3 to 5 Standard above normal
according to the 850 hpa v winds on the 00z gefs/ will be in
place...allowing for plenty of moisture to work its way into the
region. Precipitable waters will exceed 1.50 inches over much of the
area...which is about 2-3 Standard above normal for this time of year.
As a result...a line of moderate to heavy rain showers will
precede and accompany the frontal passage. A weak wave of low
pressure may develop on the front as well...which may slow down
the front/S progress as well...allowing for a prolonged period of
rainfall. This should allow for about a half inch to one inch of
rain across the entire region for Saturday. Some gusty winds will
accompany the showers as well due to the strong dynamics in place.
We won't mention thunder at this time...as instability looks to be
lacking. With the clouds/showers...it will be cooler than
Friday...with highs in the upper 50s to low 60s.
The front should be through most of the area by the evening
hours...allowing for cooler and drier air to work into the region.
With much cooler air aloft...some additional cyclonic flow/lake
enhanced rain showers will be possible downwind of Lake Ontario
for Sat night. Otherwise...showers will be ending...with
decreasing clouds through the overnight hours. Min temperatures will
range from the middle 30s to middle 40s.
Long term /Sunday through Wednesday/...
a mean upper trough will continue over eastern North America with
the axis west of our region...putting our region in the west to
southwest upper flow portion of the mean upper trough. Any lingering
showers from the exiting cold front will exit Sunday morning...but
rapidly cooling boundary layer temperatures and low level winds off
the Great Lakes...some scattered showers could extend from the lakes
into the southern Adirondacks Sunday and Sunday night. Highs Sunday
in the 50s to lower 60s.
Some disagreements in guidance/ensembles as to another upper
impulse...based more in the northern stream...possibly tracking
around the southern periphery of the upper trough and through our
region later Monday through Tuesday...with more scattered showers
and some boundary layer warming as the upper trough axis retrogrades
a little. There is a loose consensus in some warming and
retrograding of the upper trough...the disagreements are whether we
get little to no coverage of showers or better coverage of
showers...depending on the presence or non presence of well defined
upper dynamics. For now...indicating just chances for showers...but
the details how much potential for rain Tuesday will get clearer as
we get nearer to next week. Highs Monday in the upper 50s to middle
60s. Highs Tuesday in the upper 60s to around 70...with lower 60s
There are also conflicts in guidance/ensembles as to whether another
upper impulse and the leading edge of cooler air arrives Wednesday.
The rapid upper flow pattern is difficult for long range guidance to
resolve. So...just indicating showers exiting Tuesday night and
Wednesday with highs Wednesday in the middle to upper 60s...some upper
50s higher elevations.
Aviation /11z Thursday through Monday/...
system is still slowly exiting but cloud layer around 2500 feet
still lingering as moisture is being transported from the coast
inland. The northern and western edge of the rain shield is now into
central Massachusetts...so the vcsh for kpsf should continue only through about
14z. Clearing is still seen in northern and central/western
New York...but again the moist flow from the coast circulating around the
coastal system will result in a slow advance to the clearing. The
MVFR ceilings should persist until around 18z-22z...then VFR
conditions should prevail after that through the night. With mainly
clear sky tonight...with some intervals of clouds...added some MVFR
fog to kgfl and kpsf where clearing would promote the best chances
Light to calm winds through daybreak with a light north-NE flow at less
than 6 knots shifting to east-southeast as the day progresses Thursday...trending
back to variable/calm during the evening and through the night.
Friday: no operational impact. No sig weather.
Friday night: moderate operational impact. Chance of rain showers.
Saturday: high operational impact. Definite rain showers.
Saturday night: moderate operational impact. Chance of rain showers.
Sunday through monday: no operational impact. No sig weather.
along with some areas of morning fog...widespread cloud cover is
expected through at least this morning. There may be a few sprinkles
early this morning across far eastern areas as well. Relative humidity values will
drop to 50 to 60 percent this afternoon with light easterly winds.
Relative humidity values will recover to 90 to 100 percent tonight with fog and dew
formation and nearly calm winds.
After morning fog Burns off tomorrow...mostly sunny skies are
expected through much of the day Friday with relative humidity values dropping to
45 to 50 percent in the afternoon. South to southeast winds will be
5 to 10 miles per hour on Friday. A widespread wetting rainfall is expected on
a departing upper level low will allow for a few light rain showers
or sprinkles early this morning across New England. Otherwise...dry
weather is anticipated for today through tomorrow evening.
With a cold front crossing the region...a widespread rainfall is
expected between late Friday night and Saturday. Most areas will see
between one half inch and one inch of rainfall. Aside from some
puddles on roadways...this rainfall will not cause any hydrologic
issues...and will be beneficial to the region.
Mainly dry...but much cooler....weather is expected for Sunday into
Monday. Overall...area rivers and streams look to mainly hold
steady or only slightly rise through the weekend.
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.