Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Albany New York
711 PM EST Wednesday Nov 25 2015
high pressure offshore will hold its ground through
Friday. A south to southwesterly flow will bring milder air for
Thanksgiving and especially Friday. A cold front will bring
scattered showers Friday night into early Saturday followed
by cooler weather for the balance of the weekend.
Near term /until 6 am Thursday morning/...
as of 710 PM...as depicted by the 00z alb upper air flight...a
strong 1030 hpa region of high pressure is sitting over the area
indicating strong descent in the atmosphere. This will lead to
tranquil weather conditions continuing through the entire near
term period. Low temperatures have been slightly adjusted for some
areas with the warm southerly flow that will steadily increase
temperatures by Thanksgiving day morning. Some areas...especially
across the Lake George Saratoga region are experiencing
temperature cooling faster than the rest of the valley locations
so these temperatures will continue to be monitored.
In conjunction with the clear skies...some patchy fog is possible
toward the end of the near term period in areas of the middle Hudson
Valley and portions of western New England. Otherwise partly to
mostly clear skies with low temperatures tonight ranging from the
upper 20s to middle 30s across the region.
Short term /6 am Thursday morning through Saturday/...
Thanksgiving day look dry and becoming mild everywhere over
our region. If stratus were to form...it might take
awhile for it burn off...but again we lean against this
solution for now. Assuming a partly to mostly sunny sky
(some high clouds) and a breeze from the south 5-15 miles per hour...
temperatures look to reach the middle to upper 50s in the valley...
50-55 over the higher terrain.
Compare this to the last two Thanksgiving where the high
was only officially freezing. Our projected high of
55 degrees would make this the mildest Thanksgiving
since 2004 when it was 65 degrees.
Either way...conditions will be dry and optimal for travel
late today through the Holiday.
Thursday night will be mild by late November standards...
as a southerly breeze continues. Once again some stratus
might develop across portions of the region. Low
temperatures will generally be in the 40s.
By Friday...a cold front will begin pressing southward
from Canada...veering the flow to the southwest.
This looks to be our mildest day of the week.
Even some some clouds around...a south to southwest
breeze will send temperatures soaring to around 60
in the valleys...and well into the 50s across the
higher terrain. If we were to get nearly full sunshine...
we could get several degrees warmer than that. The official
record high for Friday November 27th is 66 degrees set back
in 1896. Right now...this is a long shot...but not out of
the realm of possibilities.
Friday night...the cold front will work across our region
from northwest to southeast. It will bring some scattered
showers along its leading edge and even a little behind
it. It might turn cold enough for some of these to turn
to snow showers across the Adirondacks by early Saturday
morning...perhaps leaving a dusting in a few spots.
Lows Friday night will be near 30 across the Adirondacks...
30s elsewhere across the higher terrain...to the lower
40s Albany southward.
Then it turns noticeably cooler Saturday as a small bubble of
high pressure builds. The flow does not look conducive for
any lake effect. Instead clouds will slowly give way to
increasing sunshine from northwest to southeast.
Highs only will be in the middle to upper 30s across the
the higher terrain north and west of Albany...40-45
across most of the remainder of the region...except
upper 40s across the middle Hudson Valley and lower
Long term /Saturday night through Wednesday/...
Saturday night through Monday night...latest 25/12z model and
probabilistic guidance shows a zonal flow over the region in between
a northern east-west jet across Newfoundland and a southern jet across the
far southeastern states. This will allow a broad surface high
pressure to provide tranquil weather throughout this period as we
approach the beginning of next week. Temperatures will be near
normal for late November.
Tuesday through Wednesday...latest 12z model and probabilistic
guidance show a broad upper level low pressure system setting up
over the central U.S. Where our next weather system will originate
from. Model guidance are in some accord to the fact that a
baroclinic zone set up along the Mississippi will help develop a
surface low pressure system in the Ohio Valley by Tuesday morning.
This developing low pressure system will then move northeast over
the Great Lakes near our region by Tuesday night. Some prefrontal
moisture may get into our region Tuesday morning as indicated by the
low probability of precipitation during that forecast period. Otherwise at this time...the
bulk of the precipitation will be during the day on Tuesday through
Wednesday morning. Exact timing and precipitation amounts Show Low
confidence at this time since solutions are in low agreement with
updates to the forecasts that will be made as we get closer in time
to this event. H850 and h925 winds will be out of the south
advecting warmer air into the region as a warm front may move north
of our region sometime Tuesday morning. Therefore onset
precipitation early Tuesday morning may start as some snow or a
rain/snow mix before transitioning into all rain by later Tuesday
morning. H925 temperatures well above 0c are expected by late Tuesday
morning. High temperatures on Tuesday and Wednesday will be slightly above
average for early December.
Aviation /00z Thursday through Monday/...
the center of the surface high over New England will shift off coast
tonight...however ridging will extend southward along the eastern
Seaboard through the taf period...00z/Friday. A cold front will be
gradually approaching from the west. This leave the local in between
these features. Concerns are for some stratus to move into the area
from the southeast tonight. Observations along the coast indicate
the ceilings are VFR around 3500 feet. Have these clouds mentioned
as scattered in kpsf and kpou tafs.
As for Thanksgiving day...high level cirrus clouds will stream in from
the west ahead of the approaching cold front. However...guidance indicates
low level moisture on the increase across the southern and eastern portions
of the area from the coast as a broad southwesterly flow sets up. Have
scattered 3000 foot clouds in kpou and kpsf tafs. While clouds approach from
the west ahead of the cold front. Mainly VFR conditions are expected
however moisture from the coast may result in a MVFR deck.
Light south to calm winds overnight. A southerly flow will develops
Thursday and some gusts are expected during the afternoon.
Thursday night-Fri: no operational impact. No sig weather.
Friday night: moderate operational impact. Chance of rain showers.
Sat-Mon: no operational impact. No sig weather.
no precipitation will occur through Friday afternoon.
Through Friday...relative humidity values will only fall around 50 to 70 percent
each afternoon...and recover to 90-100 percent each night with dew
and or frost formation. The wind will be light to south around 5 miles per hour.
A south wind will be around 10 miles per hour on Thursday...
and from a S-SW direction around 10-15 miles per hour on Friday.
Some light rain showers are expected with a frontal boundary for
Friday night...but rainfall amounts will generally be less than a
quarter on an inch. Dry weather and cooler will return for the weekend.
dry weather will continue through Friday...which will allow
rivers and streams to mainly hold steady or slowly fall. Some
light rain showers are expected late Friday into Friday night as
a frontal boundary crosses the area...but rainfall amounts look to
be light...mainly less than a quarter of an inch. Dry weather will
return behind this front for the weekend...and into early next
week as well.
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