Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Albany New York
955 PM EDT Sat Oct 25 2014
a cold front will move across the area tonight accompanied by rain
showers. In its wake...a brisk and cooler day is expected on
Sunday with additional showers expected. Drier and warmer
conditions return on Monday as a warm front lifts north across the
region. The next chance for showers arrives later Tuesday evening.
Near term /until 6 am Sunday morning/...
band of showers breaking up and build ing south and east into the
eastern Catskills...middle Hudson Valley and western New England.
Isolated showers and thunderstorms redeveloping on Lake Ontario
could expand and track into the region as weakened showers toward
sunrise and during the morning. Adjusted rain chances based on
current radar and satellite trends. Isolated showers also back
into the Tug Hill...headed for the southern Adirondacks. Not much
cloudiness outside of the showers. Winds should be steady from the
west and northwest...preventing temperatures from falling beyond
current forecast and winds should also prevent fog.
Short term /6 am Sunday morning through Monday night/...
Sunday...as mentioned in the excellent previous forecast
discussion...the potent upper jet core will be over the region as
strong h500 short wave dives southeastward across upstate New York. This
will set the stage for additional clouds and showers across the
region with the best concentration of those showers into the
terrain /especially downwind of Lake Ontario/. H850 temperatures plunge
back to below 0c with fairly steep low-middle level lapse rates.
Furthermore...wind magnitudes near the mixing layer heights near
h875 suggest we will effectively tap into 30kt winds. So a rather
brisk day is expected along with those showers. Due to the
clouds...showers and brisk winds...temperatures Sunday afternoon
will struggle to climb into the lower 50s for valley locations and
Sunday night...deep cyclonic flow remains across the region with
ample low level moisture. Some showers will linger...mainly across
the terrain...and as the boundary layer cools...some wet snow is
possible to mix in across the terrain. Clouds will likely begin to
break up further into the middle Hudson Valley and northwest CT which will
slowly spread northward overnight. Cloud be rather chilly night
with mainly 30s for the region /near 40f for along the Hudson/Mohawk
Monday...moderating thermal columns will be underway as surface
ridge and anticyclonic flow aloft should improve our sky condition
further. Surface temperature response should allow valley
temperatures to climb well into the 50s to near 60f for middle Hudson
Valley locations and upper 40s for the higher terrain.
Monday night...model suite are in good agreement with a passage of
a warm front lifting northward across the region. Isentropic lift
increases with the best lowering of the cpd/S mainly north and
west of Albany. In these locations...we will introduce a slight
chance for showers. Otherwise...a general increase in cloud
coverage as overnight lows remain mainly into the 40s under
increasing warm advection.
Long term /Tuesday through Saturday/...
Tuesday looks to be a relatively warm day ahead of the approaching
system and cold front...expected to affect our region Tuesday night
and Wednesday. So...intervals of clouds and sun Tuesday with highs
well into the 60s.
Upper system and associated cold front tracks into the region from
the Great Lakes and Canada...with showers ahead of and along the
cold front...then cooling behind the front. Highs Wednesday in the
middle 50s north to middle 60s south. Trailing upper energy dives south
out of Canada Thursday through Saturday...potentially becoming quite
a dynamic upper cut off low. However...the various sets of guidance
suggest very different tracks...which would result in significant
differences in potential observed weather in our region.
For now the range of possibilities seems to be tracking right over
the interior northeastern U.S. Or through the Carolinas/Virginia...
or anywhere in between. As the upper energy dives south Thursday and
Friday...wherever it ends up...however strong or weak it is...and
whatever the timing eventually is...generally more clouds than sun
with temperatures below normal. Midlevel and high clouds develop
and thicken as moisture is increasingly drawn northward into the
developing upper energy...and strengthening southerly upper jet
So...with such a huge spread in guidance out in the 6-7 day time
frame...just going with below normal high temperatures and
probabilities for showers increasing to chance by Friday and Friday
night...with isolated activity lingering into Saturday. Some
possible snow showers in higher elevations Friday night. Highs
Thursday in the middle 40s north to middle to upper 50s south. Highs
Friday in the lower to middle 40s north and around 50 to lower 50s
south. By Saturday...highs in the upper 30s north to middle to upper
Will keep an eye out for next weekend to see if something
significant does develop or if limited upstream data this far out
caused guidance to create a phantom that may disappear as we get
closer. There is still quite a range of possibilities.
Aviation /02z Sunday through Thursday/...
mostly VFR across the region outside of a band of showers that will
affect kgfl...kalb and kpsf through about 01z-02z...where some
very brief MVFR visibilities and ceilings could occur. Once this
band of showers exits...west to northwest winds will become breezy
and a broken ceiling above 3000 feet should prevail...except
around kpsf where the ceiling could lower to around 3000 feet.
After sunrise...another round of isolated/scattered showers could
affect the area...so with such low coverage...vcsh between
sunrise and 16z-18z. Ceilings should still be mainly VFR outside
of any isolated showers.
Winds south-southwest winds evening. The winds will then shift to
the west and northwest with passage of the cold front tonight and
increase in speed with gusts to 20 to 25 knots on Sunday.
Sun night-Tue: no operational impact. No sig weather.
Tuesday night-Wed: moderate operational impact. Chance of rain showers.
no significant fire weather issues are anticipated over the next
several days due to the wet weather over the past 3 to 4 days.
A cold front and an upper level disturbances will impact the
region with some scattered showers tonight into Sunday. Brisk and
cool conditions for eastern New York and western New England are
expected on Sunday. West to northwest of 10 to 20 miles per hour with some
gusts in the 30 to 35 miles per hour range will be possible Sunday afternoon.
The relative humidity values will increase to 80 to 100 percent tonight...before
slowly falling to 50 to 70 percent on Sunday afternoon.
no Hydro problems are expected the next 5 days.
Rivers flows will continue to decrease the next few days. Mainly
scattered showers are expected this evening into Sunday with
total rainfall amounts of a few hundredths to a few tenths of an
inch. Some controlled dam releases will have minimal impacts
immediately downstream on river points.
Dry weather with warming temperatures are expected Monday into
Tuesday...which will allow levels to recede further.
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.