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000 
FXUS61 KOKX 221733
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1233 PM EST Wed Feb 22 2017

.SYNOPSIS...
A weak front dissipates as it approaches this morning. High 
pressure centered well off the Carolina coast will influence the
weather through Thursday. A spring-like pattern for the end of 
this week will transition into a more seasonal pattern for the 
second half of the weekend into the beginning of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
There is still some lingering sprinkles across portions of the
Lower Hudson Valley and Long Island. These should diminish over
the next few hours. Mid and high level clouds still persist, but
think there should be enough breaks this afternoon to allow
temperatures to warm into the 50s, possibly touching 60 degrees
in the NYC metro. 

Weak front continues to dissipate as it encounters a ridge axis
and high pressure over the western Atlantic. This high will
remain in place tonight. Light southerly flow overnight will 
result in increasing low level moisture. Development of low 
stratus and fog is likely under strengthening inversion. Some
dense fog is possible, but there is uncertainty in location and
duration at this time. Low temperatures will be in the upper 
30s inland and low to mid 40s along the coast.

&&

.SHORT TERM /THURSDAY/...
Main challenge for Thursday is extent and duration of low 
clouds and fog, especially near the coast. High pressure remains
offshore with southerly flow continuing around it. Current 
expectation is that there will be dissipation of low clouds and 
fog for enough warming to push temperatures into the middle and 
upper 60s north and west of the city. Closer to the coast, 
onshore flow should hold temperatures in the upper 50s to lower 
60s. However, if low clouds hold on longer, temperatures could 
be held down.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Models in fairly good agreement with east coast ridging to end the 
week...ahead of a PAC trough sliding into the central Plains Friday 
and then phasing with a polar low to the south of Hudson bay on Sat. 
The shearing trough slides through the NE on Sunday...with generally 
zonal flow heading into early next week.

Unseasonably mild conditions continue Fri/Sat in deep SW flow ahead 
of the Pac trough and associated strong low pressure moving through 
the central US and into the Great Lakes. Although temps will be 
above normal on FRI...A PAC shortwave and associated low pressure 
moving through Southern Quebec Thursday Night will push a cold front 
through the region Thu Night/Fri. Latest GFS/NAM and high res 
solutions indicating this cold front remaining south of the region 
through Fri night...with a Canadian Maritime influence on the 
region. This would result in stratus and temps holding in the 50s 
for much of the region on Fri. Have trended forecast in that 
direction based on climatology and better resolving NAM/high-res 
solutions. With weak warm advection over the frontal boundary to the 
south...and weak shortwave energy moving through aloft...a few 
showers possible on Fri. If front remains to the south of the region 
Fri night...an increasing chance for stratus...drizzle and fog could 
be expected Friday Night into Sat morning as low-levels moisten and 
isentropic lift begins to increases.

Models in decent agreement with PAC upper low shearing into the 
northern stream low on Saturday...with associated trough and frontal 
system swinging towards the region late in the day and then though 
Sat night. Warm front should be able to gradually move north on Sat 
with strengthening llj...with temps climbing back into the 60s on 
gusty southerly flow by late in the day. Main rain activity appears 
to be along and possibly just in wake of the cold front late Sat 
into Sat eve as 40-50 kt llj and approaching shortwave energy 
interact with +2-3 std of gulf moisture and weak elevated 
instability. Potential for a brief period of moderate/heavy rain and 
even some embedded thunder with activity along the front. Heaviest 
activity though looks to be to the North and West of the region with 
stronger shortwave forcing and better .

In the wake of the front...a dry and cooler airmass will build in 
for Sat night/Sunday on gusty NW flow. Temps should cool to near 
seasonable levels for Sunday.

Lack of model consensus continues for Monday and Tuesday with 
generally weak northern stream and Pac energy moving through the 
region in a near zonal upper flow. Signals for an associated weak 
system with light precip to move through the NE/Mid Atlantic...but 
at this point does not look like much of an event. Thermal profile 
supporting would support wintry precip if precip was heavy enough.

Otherwise moderating conditions heading towards midweek...with 
considerable model spread in timing/intensity of next system.

&&

.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
High pressure off the Mid Atlantic coast will produce a weak
onshore flow across the terminals tonight and Thursday.

VFR conditions will give way to MVFR or lower after sunset as 
fog and/or low stratus begin to develop. MVFR visibilities 
initially develop after 03Z at coastal terminals before 
spreading inland around 06Z. There is still quite a bit of 
uncertainty related to the specific timing, location, and 
duration of any lower ceilings/visibilities Thursday morning. 
The best chance for IFR or lower conditions appears to be 
between 09-15Z before conditions gradually improve during the 
late morning.

Light southerly flow this afternoon will give way to light and 
variable winds at all terminals tonight before becoming SW on 
Thursday.

     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: No unscheduled amendments expected during the 
daylight hours this afternoon. Uncertainty exists in the timing
of developing MVFR or lower conditions tonight.

KLGA TAF Comments: No unscheduled amendments expected during the 
daylight hours this afternoon.  Uncertainty exists in the 
timing of developing MVFR or lower conditions tonight.

KEWR TAF Comments: No unscheduled amendments expected during the 
daylight hours this afternoon.  Uncertainty exists in the 
timing of developing MVFR or lower conditions tonight.

KTEB TAF Comments: No unscheduled amendments expected during the 
daylight hours this afternoon.  Uncertainty exists in the 
timing of developing MVFR or lower conditions tonight.

KHPN TAF Comments: No unscheduled amendments expected during the 
daylight hours this afternoon. Uncertainty exists in the timing
of developing MVFR or lower conditions tonight.

KISP TAF Comments: No unscheduled amendments expected during the 
daylight hours this afternoon.  Uncertainty exists in the 
timing of developing MVFR or lower conditions tonight.

.OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...
.18z Thursday-Saturday...MVFR or lower in stratus and fog. Chc
of light rain or drizzle.
.Saturday night...MVFR likely with rain and a slight chance of 
thunderstorms early. Gusty S winds becoming NW.
.Sunday...VFR...Gusty NW winds.
.Monday...VFR early...becoming MVFR. Chance of rain or snow. 
Winds becoming S-SW around 10 kts.

&&

.MARINE...
A relaxed pressure gradient over the waters will limit winds 
to 10 kt or less and seas to remain below small craft advisory
levels through Thursday.

Winds and seas are forecast to remain below Small Craft Advisory 
levels from Thursday Night through Friday night. Small Craft 
Advisory criteria is likely over the weekend associated with the 
approach and passage of a cold front.

&&

.HYDROLOGY...
No hydrologic impacts are expected through Thursday. 1/4/ to 3/4 
inch of rain...with locally up to an inch is possible late 
Saturday into Saturday night. No significant hydrological 
impacts are expected.

&&

.CLIMATE...
The following are record maximum minimum temperatures for 
Thursday February 23, 2017 along with the forecast minimum 
temperature.

Record Max Minimum Temperature   Forecast Minimum Temperature
------------------------------   ----------------------------
Central Park........55 (1985)    46  
LaGuardia...........54 (1985)    46
Kennedy.............47 (1990)    43 
Islip...............46 (1990)    40
Newark..............51 (1985)    45
Bridgeport..........40 (1985)    40

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$
SYNOPSIS...Fig/NV
NEAR TERM...DS
SHORT TERM...Fig/DS
LONG TERM...NV

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