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Area forecast discussion 
National Weather Service Albany New York
656 am EDT Wednesday Aug 27 2014

Synopsis...
a weak cold front will move from northwest to southeast through the
region today with little more than some clouds and widely scattered
to scattered showers and thunderstorms which will dissipate this
evening. High pressure will follow...moving from the Great Lakes
tonight to off the Atlantic Seaboard Friday night. This will result
in cooler and dry weather from late tonight through Friday night.

&&

Near term /until 6 PM this evening/...
as of 615 am EDT...skies were generally partly cloudy with some
showers approaching the western Mohawk Valley.

For today...a cold front will push into and through our region.
It will work from northwest to southeast throughout the day. Not
only is there limited moisture for the front to work with but
temperatures aloft remain rather warm limiting the instability. In
fact mlmucapes are generally less than a 1000 j/kg...except across
far southeast portions of the forecast area where they may briefly reach 1500 j/kg
this afternoon. Will forecast widely scattered to scattered
showers and thunderstorms with any thunderstorms confined to the
afternoon and early evening hours. The thunderstorms are not
expected to be severe as winds aloft remain fairly weak. Expect
highs to range from the the middle to upper 70s across the southern
Adirondacks with temperatures generally in the 80s elsewhere.

&&

Short term /6 PM this evening through Friday night/...
any shower or thunderstorm activity will end early this evening
with mainly clear skies and some fog possible later tonight as high
pressure starts to build east from the upper Great Lakes. Lows are
expected to range from the upper 40s to around 60.

On Thursday expect partly to mostly sunny skies with more in the
way of fair weather cumulus clouds across the higher terrain. High
pressure will build east into the eastern Great Lakes New York late in
the day. It will be noticeably cooler than recent days with highs
in the upper 60s to upper 70s.

Thursday night will be quite cool with mainly clear skies and
areas of fog. The high pressure center will be directly over the
forecast area late at night...so expect ideal radiational cooling to occur with
lows in the lower 40s to lower 50s.

On Friday expect high pressure to drift slowly east from the forecast area
into New England with plenty of sunshine. Highs are expected to be
in the 70s.

Friday night the ridge of high pressure will move off the New
England coast and be located south of Nova Scotia late Friday
night. A warm front is expected to move into western New York late
at night which will result in an increase in clouds during the
second half of Friday night. Lows Friday night will be in the
upper 40s to upper 50s.

&&

Long term /Saturday through Tuesday/...
warm and humid conditions are expected through the Holiday weekend
with a frontal boundary likely staying north of the majority of the
forecast area into the middle of next week.

Some shifts in the medium range and wpc guidance in the past 24
hours with the middle and upper level flow potentially becoming
slightly more amplified during the Holiday weekend. This shift will
allow downstream ridging over the western Atlantic to build in more over
New York and New England...and stall a cold front from getting through by
Labor Day.

Saturday still features a warm front lifting north and east of the
forecast area with a slight or low chance of showers...especially north and
west of the capital region. Much of this day may end up dry with
the better synoptic forcing remaining upstream. The European model (ecmwf) has been
flip flopping on this day with it being wet on the previous
run...and now dry. However...there is pretty good support from the
latest GFS and can ggem for a dry start to the Holiday weekend.
Humidity levels will be on the increase...as surface dewpoints rise into
the lower to mid60s. A weak impulse riding along the frontal
boundary near the Canadian New York border...Great Lakes region...and northern
New England may focus some isolated to scattered showers and isolated
thunderstorms Sat night. Again...low confidence here with the
trends of the strengthening middle and upper ridge near the Atlantic
Seaboard. Highs on Saturday will be in the u70s to l80s over the
forecast area...with lows mainly in the 60s with some u50s over the
higher terrain.

Sunday into Labor Day...as the previous discussion alluded to...a
short-wave trough approaching from the northern Great Lakes region will
move along the periphery of the ridge...and heights fall slightly
with the flow becoming quasi-zonal over New York and New England. The air
mass will be moist and unstable with precipitable waters exceeding 1.50 inches
over most of the area. Convection initially will be diurnally
driven north and west of the capital region on Sunday...but as this
short-wave moves along the boundary to the north of the I-90
corridor...scattered showers and thunderstorms look possible. Locally
heavy rainfall will be possible with the anomalous precipitable water air in
place. H850 temperatures in the +16c to +18c range with some sunshine
should allow highs to reach the lower to m80s in the valleys on
Sunday with some u80s possible in the middle Hudson Valley. Highs in
the m70s to l80s will be common over the hills and mountains it will be
a muggy night with lows mainly in the u50s to m60s. Labor Day is
tricky with the GFS hinting at the front buckling south towards the
capital region and Mohawk Valley...while the European model (ecmwf) guidance keeps it
north. The boundary will be a focus for scattered showers and
thunderstorms...especially in the afternoon into the early evening.
A weak surface trough may migrate through during late PM and early
evening for a wind shift to the west/northwest briefly. Highs Labor Day will
range from the 70s to l80s.

Monday night into Tuesday....the frontal boundary may lift back
northward as a warm front on Tuesday. Some isolated-scattered showers and
isolated thunderstorms will be possible again with Summer-like humidity
levels persisting. Temperatures should continue to run above normal.

&&

Aviation /12z Wednesday through Sunday/...
a cold front is approaching from the St Lawrence River
valley this morning...as high pressure will be near the middle
Atlantic region. This frontal boundary has limited low-level moisture
to work with and will bring isolated/scattered showers and thunderstorms to
parts of eastern New York and western New England this afternoon into the early
evening.

VFR conditions will prevail the next 24 hours at kalb and kpou.
Middle and high clouds will increase ahead of the boundary between
12z-15z for all the taf sites. Cumulus clouds will generally be in
the 4-6 kft above ground level range with any showers/isolated thunderstorms and rain showers. Vcsh groups
were used at kgfl/kalb/kpsf between 17z-22z for possibility of isolated
maybe scattered rain showers or isolated thunderstorms and rain showers. The probs are too low to include
thunderstorms at this time.

The front should clear the taf sites by the middle to late PM. The
winds will shift to the west/northwest at less than 10 kts...and the skies
will clear towards 00z/Thursday with just some scattered-broken middle or high
clouds around...especially south and east of kalb.

Some IFR/LIFR mist/fog will be possible at kgfl/kpsf...as the
boundary layer winds will decouple from the surface. The best chance for
this to happen is after 06z/Thu.

The winds will increase from the S to SW at 4-8 kts prior to
noontime..before shifting to west to northwest at 5-10 kts in the late
PM...before becoming light to calm shortly after 00z/Thu.

Outlook...

Thursday to Friday night: no operational impact. No sig weather.
Saturday: low operational impact. Slight chance of rain showers...tsra.
Saturday night: moderate operational impact. Chance of
rain showers...tsra.
Sunday: moderate operational impact. Chance of rain showers...tsra.



&&

Fire weather...
a weak cold front will move from northwest to southeast through the
region today with little more than some clouds and widely scattered
to scattered showers and thunderstorms which will dissipate this
evening. High pressure will follow...moving from the Great Lakes
tonight to off the Atlantic Seaboard Friday night. This will result
in cooler and dry weather from late tonight through Friday night.

Relative humidities will drop to 40 to 65 percent today...recover
to 80 to 100 percent tonight...and fall to 40 to 55 percent on
Thursday.

Winds will generally be southwest to west at 5 to 10 miles per hour today...
light and variable tonight...and northwest at 10 to 15 miles per hour on
Thursday.

&&

Hydrology...
a cold front will drop from northwest to southeast across the forecast area
today. It will bring widely scattered to scattered showers and
thunderstorms to the hsa...with the thunderstorms confined to the
afternoon and evening hours. Basin average rainfall will be a
quarter of an inch or less. This will have little to no effect on
area rivers and streams. Another stretch of dry weather is
expected from late tonight through Friday night as high pressure
returns to the region and then moves out to sea late Friday night.
This will allow rivers to mainly hold steady or fall slightly during
the remainder of the week. The threat for scattered showers and
thunderstorms will return to the region during 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.

&&

Aly watches/warnings/advisories...
CT...none.
New York...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...okeefe/11/Snyder
near term...11
short term...11
long term...wasula
aviation...wasula
fire weather...11
hydrology...11

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