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000
FXUS61 KPHI 210734
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
334 AM EDT Thu Sep 21 2017

.SYNOPSIS...

Tropical storm Jose will move slowly north and northeastward off the
southeast New England coastline through tonight. Jose will then
weaken and drift slowly westward through the weekend. High pressure
will continue to slowly build eastward into the region and become
firmly established for the remainder of the week into early next
week. Hurricane Maria will move northward into the southern Atlantic
waters staying offshore during the early and middle part of next
week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

The mid level ridge over the eastern half of the country will keep
our region warm and precipitation-free for today. Meanwhile, the
center of Tropical Storm Jose will remain about 350 miles east of
the New Jersey coast. The system is forecast to continue throwing
some cirrus back toward our region. The high clouds should be mostly
thin allowing for plenty of sunshine for this last full day of
summer.

Maximum temperatures are expected to be mostly in the 80s this
afternoon. Readings should be about 10 degrees above normal. We are
anticipating a northerly wind increasing around 10 MPH.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...

Dry weather is forecast to continue for tonight as the ridge remains
overhead and as Jose moves very slowly westward. High clouds are
expected.

The wind direction should favor the north at speeds of 7 MPH or
less. Minimum temperatures are anticipated to favor the upper 50s
and lower 60s in our region.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...

Jose will continue an eastward/northeastward movement away from our
region as high pressure continues to become established over the
region.

Sunshine will also be ample with mid-level temperatures quite warm
for mid-September yield highs in the 80`s for a good portion of
the region after starting warm in the 60`s. MAV/MET in better
alignment with this now through Saturday. Temperatures will
likely be several degrees warmer than the mean of the ensemble
guidance based on the anomalous warm pattern expected by Sunday.
Highs Sunday may make a run at 90 in a few spots.

Monday through Wednesday:

Ensemble guidance continues to show a much weaker Jose making a loop
back to the southwest by early next week but at a very slow pace. It
would not be surprising to see Jose decay totally before it would
reach our area. Will continue with the slight to low shower chances
south and east of Philadelphia for the early part of next week from
whatever is left of Jose. Moisture may move into the region from
Maria as well to keep these chances going through Wednesday.

Ridging will continue to be firmly in place over the region with a
strong - PNA pattern of almost four standard deviations. A similar
theme of anomalous warmth will likely continue as well and ensemble
guidance may still be playing catch up to the pattern that is
expected to occur. Highs were raised a couple of degrees from the
ensemble mean with a few locations making a run close to 90 on
Monday as well. Stayed closer to the mean of the ensemble guidance
for Tuesday and Wednesday given the uncertainty with Jose and Maria.
NHC/WPC forecast guidance currently shows Maria remaining to our
southeast and staying offshore through the middle of next week. Stay
tuned to the latest advisories and forecasts from the National
Hurricane forecast for more information on Jose and Maria.

&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

VFR conditions are forecast through the TAF period with one
exception. Patchy fog may develop around KRDG along the Schuylkill
River during the early morning hours.

A northerly wind around 6 to 10 knots is expected for today. Wind
speeds will likely diminish to 6 knots or less for tonight.

Outlook...

Friday through Monday: VFR. Winds generally 10 knots
or less. Northerly wind gusts around 15 knots Friday afternoon.

&&

.MARINE...

A north to northwest wind is expected on our waters for today and
tonight. Speeds are anticipated to favor the 8 to 16 knot range.

Wave heights on our ocean waters will likely remain in the 4 to 6
foot neighborhood. As a result, a Small Craft Advisory is in effect
there. Waves on Delaware Bay are forecast to be 1 to 3 feet, perhaps
reaching 4 feet near the mouth of the bay.

Outlook...

Seas are expected to remain above five feet throughout the outlook
period and the SCA was extended till 10z Saturday on the coastal
waters. Wavewatch is likely being too aggressive in reducing
swells and wave heights from Jose. Additional swell and
increased wave heights are likely by early next week in
association with Maria. Wind gusts are expected to be under 25
knots.

Rip Currents...

Long period swells of 4 to 5 feet emanating from Tropical Storm Jose
will continue to reach the coasts of Delaware and New Jersey today.
As a result, we will carry a high risk for the development of
dangerous rip currents.

Outlook:

Friday and Saturday a moderate or high risk.

Sunday through Wednesday are outlooked HIGH risk days with the
greatest risk Tuesday or Wednesday of next week. Leftover Jose
swells combined with newly arriving southeast swells from Maria.

&&

.TIDES/COASTAL FLOODING...

The potential for widesperad minor flooding has decreased for today
along the coasts of Delaware and New Jersey and on the upper eastern
shore of Chesapeake Bay. While localized minor flooding is expected
around the times of high tide, the flooding should not be widespread
or impactful enough to warrant another Coastal Flood Advisory.

We will continue to keep an eye on Jose and the system`s
possible impact on tide level on Friday.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...High Rip Current Risk through this evening for NJZ014-024>026.
DE...High Rip Current Risk through this evening for DEZ004.
MD...None.
MARINE...Small Craft Advisory for hazardous seas until 6 AM EDT
     Saturday for ANZ450>455.

&&

$$
Synopsis...Gaines
Near Term...Iovino
Short Term...Iovino
Long Term...Gaines
Aviation...Gaines/Iovino
Marine...Gaines/Iovino
Tides/Coastal Flooding...