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Area forecast discussion 
National Weather Service Mount Holly New Jersey
402 am EST Thursday Nov 26 2015

strong high pressure will continue to progress northeastward,
cresting to the south of Newfoundland later today. A cold front will
cross our region Saturday followed by high pressure to the north
building toward the area Sunday and Monday. Unsettled weather is
expected Tuesday into early Wednesday as strengthening low pressure
lifts north through the Great Lakes and a cold front crosses the
middle-Atlantic region.


Near term /until 6 PM this evening/...
overall, we should give thanks to the weather for this Thanksgiving. It
will be a cold start to the day with temperatures warming into the
30s and 40s, so bring a jacket if attending a parade this morning.
Depending on personal tolerance, you may not need a jacket for the
afternoon, especially from phila southward where highs will be in
the 60s.

A strong 1050 mb surface high was located over Nova Scotia early
this morning while its ridge axis extends south and eastward along
the eastward Seaboard.

S-southwesterly low-level winds (below 700 mb) around the ridge will produce
a warm air advection pattern over the County Warning Area today. Compared to yesterday, 925-850 mb
temperatures today are forecast to average 6c (11f) higher. Did not go
quite that much warmer for maximum temperatures today as it will be difficult
to fully mix down the warm air owing to low sun angle and with high
clouds filtering the sunshine at times. Forecast highs are close to
10f above normal for most of the area, ranging from near 50f in the
Poconos to middle 60s toward the lower Delaware-Maryland-Virginia.

The ridge axis of the surface high, which currently bisects our cwa,
is expected to shift slightly southward, which will allow the
surface winds to veer more out of the south today. Expect wind
speeds to generally be under 10 miles per hour.


Short term /6 PM this evening through 6 am Friday/...
expect light winds and boundary-layer decoupling tonight with the
surface ridge axis over the area. The setup for fog should be
slightly better tonight than in recent ones with return flow around
the high helping to draw moisture back into the middle-Atlantic region.
The high clouds will play a factor in determining the extent of the
fog. If clouds winds up being more overcast and dense, it may keep
fog rather patchy. Forecast soundings from the NAM also hints at the
development of stratus County Warning Area-wide while the GFS confines the potential
stratus to the coastal plain.

Forecast min temperatures comprised of a mav/met blend. Expect lows to be
10-15 degrees warmer tonight than last night.


Long term /Friday through Wednesday/...
a mild start to the long term period Friday as strong departing high
pressure will continue to influence the middle Atlantic Seaboard. The
day may begin with some patchy morning fog across the region with a
southeasterly onshore flow leading to an uptick in low level
moisture. Otherwise, a dry and rather warm late November day is in
store as daytime temperatures top out some 10 to 12 degrees above
average, with highs ranging from the 50s across the north to the
lower and middle 60s from the Delaware valley to central/southern New Jersey
and the Delaware-Maryland-Virginia.

By overnight Friday into early Saturday morning, a cold front will
be approaching our region from the northwest. Moisture continues to
appear relatively limited with this boundary, but we have kept some
low chance probability of precipitation for showers as the front gradually passes from
northwest to southeast across the forecast area from late Friday
night through Saturday. This front may tend to get hung up across
southern parts of the forecast area into Sunday, and we have kept
some low probability of precipitation in place mainly across southern New Jersey and the Delaware-Maryland-Virginia
from Saturday night through Sunday. As noted by the previous shift,
overall precipitation amounts with this frontal passage continue to look
unimpressive as generally under half of an inch of rainfall is
expected. Also to consider from Sunday into Monday will be an area
of high pressure across southern Canada beginning to build south
toward the region, and this may help to limit the extent of any
lingering showers Sunday across our forecast area. This high
pressure will certainly aid in bringing a noticeably cooler airmass
into the region over the weekend and into Monday as temperatures
tumble back to seasonal averages, with daytime highs Sunday and
Monday mainly in the 40s to lower 50s across the region.

There continues to be a fair amount of uncertainty with the latter
part of the long term period, but there is a little more similarity
in latest 00z model solutions as compared to 24 hours ago. Of note,
the GFS and European model (ecmwf) both develop low pressure around the lower Ohio
Valley Monday night. This low is forecast to then strengthen as it
lifts north across the Great Lakes into Tuesday and Tuesday night,
with an associated cold front prognosticated to cross our area late Tuesday
night to early morning Wednesday. Even though there are some
similarities, there are still notable differences in the track and
strength of the low pressure through the Great Lakes, as well as the
amount of moisture with the frontal passage across our area. With
the latest 00z European model (ecmwf) still developing a stronger low pressure and
cold front, it continues to be the wetter solution for our forecast
area Tuesday to Tuesday night as compared to the GFS. We have kept
the idea of high chance probability of precipitation for Tuesday to Tuesday night for the
forecast area and blended in the latest wpc and superblend guidance
for temperatures, winds, and other elements through Tuesday and


Aviation /09z Thursday through Monday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.

VFR today. Light/variable winds under 5 knots through about 15z will
become southeasterly late this morning and southerly this afternoon with speeds of
5-8 knots.

There is a potential for low clouds and/or fog to develop late
tonight (generally after 06z except maybe earlier near the coast).
The fog may wind up being patchy though with broken to overcast hi clouds
overhead. Any stratus would be favored near the coast (in vc of Acy/
miv) due to an onshore flow.


Friday...mainly VFR conditions are expected. Some patchy fog is
possible in the morning, and some lower ceilings may also develop
with southeast, onshore winds.

Friday night and Saturday...some sub-VFR conditions possible at
times in showers as a cold front crosses the area.

Sunday and Monday...mainly VFR conditions. Slight chance for some
showers, especially across the southern terminals.


southeasterly winds 5-10 knots are forecast for today and tonight.

Seas in the coastal Atlantic are forecast to increase gradually through
tonight in accordance with a building medium-period southeasterly swell. Went
conservative with the wave height forecast for tonight compared to
the wave watch guidance as it tends to be overdone in these setups.
With the support from the latest Swan output, felt that there was
enough confidence to issue a Small Craft Advisory for hazardous seas for our coastal
Atlantic waters south of Cape May. The Small Craft Advisory GOES into effect late


Friday...a Small Craft Advisory has been raised for hazardous seas
for most of our Atlantic coastal waters, except off of the far
northern New Jersey coast. Seas are expected to steadily rise into the 5 to
6 foot range during the daytime Friday. This Small Craft Advisory may eventually need
to be extended to include the waters off the Monmouth County coast,
but since wavewatch guidance can tend to increase seas a little too
quickly in a southerly flow, we decided to hold off any headlines
for now.

Saturday...hazardous seas may continue for our Atlantic coastal
waters, and the Small Craft Advisory flag may need to be extended in time.

Sunday...winds and seas below Small Craft Advisory levels are expected.

Monday...onshore flow may lead to another period of hazardous seas
for our waters, with waves into the 5 to 6 foot range possible.


the following locations may experience near record warmth Friday
November 27, presuming there is considerable sunshine from midday-
early afternoon Onward with a south to southwest wind of around 10
miles per hour. All guidance is now in agreement favoring a very nice day for
the first big shopping day after Thanksgiving...after any early
morning clouds/fog and mex/ece MOS almost identical to each other.

Of the records appears kmpo is least likely to
approach, holding in the 50s.

Record highs for Friday November 27
kabe 62 -1988 and 1959
krdg 65- 2011
kmpo 60- 2006 and 1984
kacy 69- 1981


Phi watches/warnings/advisories...
New Jersey...none.
Marine...Small Craft Advisory for hazardous seas from noon Friday to 6
am EST Saturday for anz451>453.
Small Craft Advisory for hazardous seas from 3 am Friday to 6
am EST Saturday for anz454-455.


near term...Klein
short term...Klein
long term...Kline

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