Area Forecast Discussion
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FXUS61 KOKX 211946
Area Forecast Discussion
National Weather Service New York NY
346 PM EDT Tue Mar 21 2017
A polar front crosses the region tonight. High pressure moves
into the Great Lakes Wednesday and then over the area Thursday
and pushes offshore Thursday night. A warm front approaches
Friday and remains in the vicinity through Saturday. A backdoor
cold front moves through Saturday night. Another frontal system
affects the region for the beginning of next week.
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Weak trough pushes through late this aft/early evening...with
mild westerly flow across the region.
Digging polar trough approaches tonight...with polar front
crossing the region late tonight. Passage is expected to be
dry...with main impact strong caa on strengthening NW winds
heading into daybreak.
Lows generally falling into the 20s interior and near freezing
for the coast tonight...with windchills falling into the teens
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Polar trough pivots through the region on Wednesday...with polar
front pushing offshore.
Breezy NW flow expected through the day with deep mixing and tight
gradient between polar high and developing Canadian Maritimes low.
Frequent gusts of 35 to 40 mph likely...with isolated 45-50 mph
gusts potential based on winds at top of mixed layer.
Scattered aft instability cu likely under the
shortwave late tonight through Wed AM...but downslope flow and
diminishing instability over the lakes do not support
maintenance of flurry/snow shower activity into the area.
Unseasonably cold temps expected on Wednesday...with temps
struggling to rise much from morning lows during the day as polar
air advects into the region. Highs generally in the lower 30s to 35
city/coast and upper 20s to 30 for the interior.
Polar trough slides east Wed Night with high pressure building in
from the west. A gradual subsiding of winds expected as a result.
The mixed low-levels should limit radiational cooling...but still
expecting temps to fall down into the teens for most of the
region...except around 20 NYC metro. If decoupling occurs...temps
would likely drop well down into the single digits across interior
.LONG TERM /THURSDAY THROUGH TUESDAY/...
There is some uncertainty in this time frame, especially Saturday
and Sunday with placement of a warm front/back door cold front.
Thereafter, there is uncertainty with an area of low pressure that
rides a frontal boundary for the beginning of next week.
High pressure moves over the region and pushes off the East Coast
Thursday into Thursday night. This will allow a warm front to move
toward the region on Friday. Ridging aloft over the Western Great
Lakes region Thursday night flattens as it moves east.
The warm front remains in the vicinity on Saturday. As previously
mentioned, there is some uncertainty with where the warm front will
be late Friday into early Saturday, which could lead to uncertainty
in temperature forecasts and amount of precipitation. However, the
warm front should move back south as a back door cold front Saturday
into Saturday night.
Thereafter, weak surface low over the mid-West moves toward the
region, riding along the cold front, then passes well south of the
region. 12Z Canadian and 00Z ECMWF are in good agreement with this
feature in placement and timing, while the 12Z GFS is too far north
and redevelops a second low offshore a bit too late.
With the frontal boundaries in the vicinity as well as a weak area
of low pressure passing south of the area, it will be fairly
unsettled for this time period. Temperatures should average below
normal, with the exception of Saturday when we will see slightly
above normal temperatures with the warm front north of the area.
Again, there is some uncertainty with temperatures due to
exact placement of the front.
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
A trough of low pressure exits east this afternoon followed by a
cold front tonight.
VFR. Winds around 10 kt or less this aftn varying mostly SW to NW
depending on the terminal. Winds WNW-WNW this evening. Sea breezes
east of city terminals.
NY Metro Enhanced Aviation Weather Support...
Detailed information, including hourly TAF wind component forecasts,
can be found at: http:/www.weather.gov/zny/n90
KJFK TAF Comments: Shift to WNW might be an hour or two off.
KLGA TAF Comments: No unscheduled amendments expected.
KEWR TAF Comments: No unscheduled amendments expected.
KTEB TAF Comments: No unscheduled amendments expected.
KHPN TAF Comments: No unscheduled amendments expected.
KISP TAF Comments: Chance that sea breeze retreats and winds shift
back to SW briefly at some point before 23z.
.OUTLOOK FOR 18z WEDNESDAY THROUGH SUNDAY...
.Weds...VFR. NW Gusts 30-35 kt.
.Friday...CHC PM shra/mvfr. SW gusts 25 kt.
.Sunday...MVFR/IFR and rain. E gusts 20-25 kt.
Gale conditions expected early Wednesday AM into Wednesday
evening due to tight gradient and strong caa in wake of polar
frontal passage late tonight...with ocean seas building to 4 to
7 ft and 3 to 5 ft on LI Sound. Winds should gradually fall
through SCA Wed night into Thu morning and remain below through
Thereafter, gusts 25 to 30 kt are possible late Friday into
Friday night for the ocean waters as a warm front approaches the
waters. Winds should fall below SCA criteria Sat through
Sunday. SCA winds are possible on the ocean waters late Sunday
night through Monday night as weak low pressure passes south of
the waters. Waves will remain below 5 ft through Friday. Waves
build up to 6 ft on the ocean waters Friday night, diminishing
below SCA criteria by Saturday morning. Thereafter SCA waves are
possible from Sunday night through the beginning of next week.
NW winds of 15 to 25 mph with gusts 35 to 40 mph and min RH`s in
the 20s should help dry fine fuels across the snow barren
grounds of LI and Coastal SE CT. This will enhance the threat
for brush fire spread.
Between 1 and 2 inches of QPF is possible this weekend into
early next week. However, this will fall over an extended
period of time and no hydrologic concerns are anticipated.
The following are record low temperatures for Thursday March
23, 2017 along with the forecast low temperatures.
Record Low Temperature Forecast Low Temperature
Central Park........12 (1875) 18
LaGuardia...........20 (1959) 21
Kennedy.............20 (1959) 20
Islip...............15 (2004) 15
Newark..............13 (1934) 17
Bridgeport..........19 (2004) 15
MARINE...Gale Warning from 6 AM Wednesday to 2 AM EDT Thursday for