Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 110944

Area Forecast Discussion
National Weather Service New York NY
544 AM EDT Tue Aug 11 2020

A broad area of high pressure will continue to drift east over
the Atlantic today. A cold front will approach tonight before
stalling over the region through the end of the week. High
pressure builds in for the weekend.


The forecast remains on track early this morning with only minor
updates to temperatures and dew points over the next few hours
to better capture the latest trends.

Heat and humidity will continue today as surface high pressure
drifts east over the Atlantic. Much like yesterday, high
temperatures will rise into the lower 90s for locations from New
York City north and west, and into the mid to upper 80s across
Long Island and coastal Connecticut. With dew points remaining
around 70 through the day, this will again result in heat index
values in the mid 90s across much of the area. The Heat Advisory
remains in effect through Wednesday for all but Suffolk County
in New York and southern Middlesex and New London counties in

Once again, can`t completely rule out a few diurnally driven
showers and thunderstorms this afternoon and evening, but
forcing remains limited. The best chances for any precipitation
today will be across the interior.

There is a moderate risk of rip currents at Atlantic Ocean
beaches today.


Any showers and thunderstorms that do develop will quickly
diminish after sunset with the loss of daytime heating.
Meanwhile, a cold front will begin to approach from the west
overnight before stalling across the area during the day on
Wednesday. While much of the region will remain dry through the
overnight hours, showers and thunderstorms ahead of the front
could work eastward into portions of the Lower Hudson Valley
after midnight. The better precipitation chances come during
the day on Wednesday as the front stalls across the area, with
showers and thunderstorms possible across much of the area.

While increased cloud cover on Wednesday will likely help hold
temperatures a few degrees lower than earlier in the week, dew
points will rise as moisture begins to pool along the front,
resulting in another day with heat index values in the mid 90s
across much of the area.


With the cold front remaining stalled across the area, shower
and thunderstorm chances will continue through the beginning of
the long term period. Some h5 energy embedded in the weak flow
is progged to pass along and north of the surface front Thu and
Fri. This would bring chances for shwrs and tstms each day. The
energy is likely remnant upstream convection however, so
confidence in timing, placement, and coverage is very low and
probabilities were capped at the chance level. With precipitable
water values increasing to around 2 inches on Thursday and weak
flow aloft, can`t rule out the potential for minor flooding
with any showers/storms. The NBM with local adjustments was used
for temps.

High pres builds in from ern Canada over the weekend. The
latest 12Z model data suggests the influence will be strong
enough to keep the cwa dry all weekend. Would prefer to see some
consistency before pulling all pops attm, but numbers were
limited to 20 percent or less, which was blw the NBM. Temps
again based on the NBM.

A warm front possible for Mon. Pops were limited to slight
chance as this is too far out for any timing confidence.


Western Atlantic high pressure will be in control today.

Mainly VFR through the forecast period. This morning, stratus
is likely to develop at GON, with some MVFR visibility at HPN.
There is a lower chance for fog/stratus out ISP and BDR.

Later this afternoon, an isolated shower or thunderstorm is
possible, mainly north and west of the NYC terminals.

S-SW winds around 5 kt this morning will increasing after
sunrise to around 5-10kt. Coastal terminals will see higher wind
speeds as afternoon seabreezes develop.

.Tue Night...VFR. Isolated shower or thunderstorm possible in
.Wed-Thu...Chance for afternoon/evening showers and
thunderstorms with MVFR or lower conds.
.Fri-Sat...Chance of showers and MVFR or lower conditions in
shower. Slight chance of thunderstorms.


Winds and seas will remain below SCA criteria through Friday
night. Increased ely flow behind a cold front over the weekend
could produce sca conditions, especially on the ocean.


Precipitable water values will increase to around 2 inches
Wednesday night into Thursday as a cold front stalls across the
area. With weak flow aloft, minor flooding will be possible in
any showers and thunderstorms, primarily in urban and other
poor drainage areas.


CT...Heat Advisory until 8 PM EDT Wednesday for CTZ005>010.
NY...Heat Advisory until 8 PM EDT Wednesday for NYZ067>075-176>179.
NJ...Heat Advisory until 8 PM EDT Wednesday for NJZ002-004-006-


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