Area Forecast Discussion
Issued by NWS Albany, NY
FXUS61 KALY 271740
Area Forecast Discussion
National Weather Service Albany NY
140 PM EDT TUE SEP 27 2016
The occluded front will move across New England
this afternoon...as increasing afternoon sunshine will yield above
normal temperatures. Fair and mainly dry weather is expected tonight
into Wednesday. Unsettled weather returns Thursday into the weekend
as a slow moving low pressure system near the Ohio Valley brings
scattered showers to eastern New York and New England.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 900 AM EDT...The showers/rain have ended yet just on the
back edge of the clearing some dense fog has quickly developed
(also observed here at our forecast office). 12Z sounding reveals
the moist low levels with a very dry column aloft. Furthermore,
westerly winds increase between 2-3K feet so we expect mixing to
occur which should aid in eroding the low stratus/fog through the
morning hours. Otherwise, 1km visible imagery shows several breaks
in the overcast to a mostly sunny sky just upstream as this trend
should translate eastward with the dry slot now moving in...
So the subsidence in the wake of the front will allow for
clearing skies from west to east in the late morning into the
afternoon. The dry slot associated with strong cutoff low pressure
system over the western Great Lakes Region and Upper Midwest will
move over the region. In the southwest flow aloft...H850 temps
will be +8C to +10C over the region. Expect above normal temps for
late Sept with lower to mid 70s in the Mohawk...Hudson and CT
River Valleys...and mid and upper 60s over the hills and mtns.
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
Tonight...A quiet night is expected with a weak sfc high moving in
over NY and New England in the southwest flow aloft. Light winds
and mostly clear/partly cloudy conditions will allow for
radiational cooling and some patchy fog formation in the major
river valleys. The low-level flow will become east or southeast
and this may focus some isolated showers across the higher terrain
of western New England during daybreak. Lows will be in the 40s to
lower 50s with a few upper 30s in the southern Adirondacks.
Wed-Wed night...The cut-off low centered over the Midwest will dig
further south and east. The long-wave trough with the embedded
cutoff will be mainly east of MS River Valley. Isolated showers or
drizzle is possible south and east of the Hudson River Valley
during the day. Partly to mostly cloudy conditions will persist
further west. It will be cooler than TUE with more clouds than sun
with the onshore flow. Highs will be in the 60s with some upper
50s over the southern Greens and northern Berkshires...portions of
the southern Adirondacks...and eastern Catskills. A few lower 70s
are possible in the mid-Hudson River Valley. Wed night...a short-
wave along the eastern flank of the cutoff lifts north-northeast.
Some of the moisture associated with this short-wave may get into
portions of the forecast area based on the GFS and some of the
GEFS...but the latest NAM and EC keep it mainly dry WEd night with
the short-wave and over running moisture from a frontal boundary
east of the stacked low staying south and west of the forecast
area. Slight and low chc pops were used overnight with temps in
the mid 40s to lower 50s.
Thu-Thu night...Cutoffs are always challenging to forecast in
terms of the timing of rain and the amounts /CSTAR research has
shown this over the years/. The guidance is converging on the
threat increasing for scattered showers during this time frame and
east to southeast h850-700 low-level flow increasing. A front
actually sets up over NY and PA with the cutoff still well to the
south and west of the region...and high pressure trying to build
in from southeast Quebec and Northern New England. The convergence
along this front and the onshore fetch of Atlantic moisture will
increase the chances for showers and damp conditions. Temps will
be a shade cooler during the day...and similar to the previous
nights mins in maritime air mass.
.LONG TERM /FRIDAY THROUGH MONDAY/...
A vertically stacked low pressure system will impact the forecast
through the period. Guidance has come into somewhat better agreement
however uncertainty definitely remains. Guidance indicates the low
is expected to be located over the Tennessee Valley/Ohio Valley by
Friday morning. It is then expected to begin to drift back northward
moving over the Great Lakes region over the weekend as it fills and
weakens. A northeastward movement across the Northeast is indicated
for Monday. Winds will be light with an onshore easterly flow bringing
in moisture off the Atlantic. Overall looking at an unsettled, mostly
cloudy forecast with chances for showers each day. as for temperatures,
near seasonable daytime highs with above normal nighttime readings
due to the cloud cover.
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Low stratus clouds have finally lifted early this afternoon, with
cumulus clouds in VFR range developing across the region. These
clouds should dissipate this evening with loss of daytime heating,
leaving mainly clear skies. We are not expecting the dry air in
western/central NY to make it to eastern NY and western New England
before nightfall, so radiation fog development is expected to occur
at the KALB/KPOU/KPSF/KGFL terminals tonight. Will mention
conditions deteriorating to MVFR then IFR at starting around 04Z to
Fog will likely dissipate by 13Z-14Z Wednesday, as northeast winds
develop in response to low pressure slowly moving east from the
Midwest and high pressure settling southward across eastern Quebec.
However, is anticipated that fog will lift to a low stratus cloud
deck in MVFR range through at least 18Z Wednesday.
Winds will be variable at 5 kt or less, becoming calm tonight. Winds
will shift to the northeast around 5 to 10 kt on Wednesday.
Wednesday Night: Moderate Operational Impact. Chance of SHRA.
Thursday: Moderate Operational Impact. Chance of SHRA.
Thursday Night: Moderate Operational Impact. Chance of SHRA.
Friday: Moderate Operational Impact. Chance of SHRA.
Friday Night: Moderate Operational Impact. Chance of SHRA.
Saturday: Moderate Operational Impact. Chance of SHRA.
Saturday Night: Moderate Operational Impact. Chance of SHRA.
Sunday: Moderate Operational Impact. Chance of SHRA.
Showers will end this morning as the occluded
front moves across New England...as increasing afternoon sunshine
will yield above normal temperatures. Fair and mainly dry weather
is expected tonight into Wednesday. Unsettled weather returns
Thursday into the weekend as a slow moving low pressure system
near the Ohio Valley brings scattered showers to eastern New York
and New England.
The RH values will lower to 40 to 55 percent this afternoon...and
have an excellent recovering to 90 to 100 percent tonight. They
will lower only to 45 to 65 percent Wednesday afternoon.
The winds will shift to the southwest to west at 5 to 10 mph for
today...and become light to calm tonight. The winds will vary from
the northeast to southeast at 5 to 10 mph on Wednesday.
No widespread hydro issues are expected the next 5 days ending on
Total rainfall amounts of one tenth to a half of an inch are
expected from the occluded front this morning. A brief spell of
dry weather is expected this afternoon into most of Wednesday.
There is an isolated threat of showers east of the Hudson River
Valley on Wed.
Isolated to scattered showers may return Wednesday night into
Saturday with a cutoff cyclone. The amount of rainfall is
uncertain during the stretch...but totals of a quarter to three
quarters of an inch will be possible in some locations depending
on the track of the cutoff.
The U.S. Drought Monitor released on September 22nd shows drought
conditions have changed very little across the region. The next
issuance will be on September 29th. For details visit:
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