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Area forecast discussion 
National Weather Service Mount Holly New Jersey
1011 am EDT Sat Apr 25 2015

Synopsis...
weak high pressure covers our area today. Low pressure over the
lower Ohio Valley will pass off the North Carolina coast Sunday.
That low becomes part of large low pressure circulation over the
northwest Atlantic early next week. A low pressure system over the
northern Gulf of Mexico Tuesday night emerges off the southeastern
Seaboard late Wednesday and Thursday and heads northeast.

&&

Near term /until 6 PM this evening/...
with the middle-morning update, the main adjustments were to hourly
temperatures as temperatures overall have been slower to rise, especially
through the Delaware-Maryland-Virginia where the cloud cover is the thickest. Some
adjustments to sky cover were also made. In addition, we added
sprinkles for a couple of hours this morning through portions of
the Delaware-Maryland-Virginia based on latest radar returns as some very light
rain occurred to our west at kbwi.

Otherwise, variable high cloud cover through today. The thicker
skycover from far southeast PA and snj southward. Sprinkles may develop
toward 6 PM over Talbot/Caroline and southern Sussex counties on
the SW edge of our forecast area. Forecast temperatures today were a
1/3rd blend of the 00z/25 GFS/NAM MOS and 00z/25 European model (ecmwf) 2m temperatures.
The European model (ecmwf) is quite cool under the clouds over the Delaware-Maryland-Virginia and
have modified the NCEP MOS downward there. Warmest temperatures in our
forecast area today should be in northern New Jersey where there should be
more sunshine.

A nice day with much less wind than the previous Wednesday-Thu-Friday
afternoons.

Daytimes temperatures will be warming a bit except the Delaware-Maryland-Virginia where it
will be chilly today and maximum temperatures almost 15 degrees below
normal while maximum temperatures around Allentown and Mount
Pocono northeastward through nnj should only be 8 to 10 degrees below
normal.

A weak wind shift boundary will be forming just to our north late
in the day with westerly winds gusting to 15 miles per hour during the
afternoon in PA and nnj but sea breezes should develop coastal New Jersey
and coastal Delaware. Winds on the Delaware-Maryland-Virginia will be light where less
mixing is expected due to heavier skycover.

&&

Short term /6 PM this evening through 6 am Sunday/...
tonight...thick high cloud along and south of I-78, with the northern
portion of the forecast rain shield a blend of HPC qpf, 50 50
00z/25 NAM/GFS MOS and multi model .10 in 6 hours. That means mainly
the southernmost 40 miles of our cwa, Talbot County, Queen Annes
and Caroline counties in Maryland and Sussex County de, possibly Kent
County Delaware and possibly the southern tip of New Jersey. This cloud cover today
and cloud cover/rain tonight is associated with the low redeveloping
near the NC coast. A wind shift from light west to north-northeast
progresses from north to south through our County Warning Area during the night.

Patchy frost is in the forecast north of I-78 tonight. No new frost advisory
at this time due to the uncertainty of the northern edge of thick cloud
cover. It already froze up there this morning so early susceptible
blooms were probably damaged.

&&

Long term /Sunday through Friday/...
a low pressure system will be moving offshore Sunday morning and
its associated clouds and light rains will be affecting the southern
parts of our area. Some light rain will pull away by evening with
perhaps up to a tenth of an inch possible. Elsewhere...partly to
mostly sunny north and central areas with temperatures near
normal.

Cooler air arrives for Monday and Tuesday as the large upper low
offshore rotates a few short waves and surface troughs across the
area. Scattered showers are expected Monday with chance probability of precipitation. Drier air
arrives Tuesday...but still a slight chance for a shower far north.
Temperatures will run several degrees below normal Mon/Tue...with
Tuesday likely the milder day.

The European model (ecmwf)/GFS models both show another surface/upper low strengthening
across the southeast states and moving northeast...just east of
our area. It appears to be another glancing shot of clouds and
rains S/east for Thursday and into early Friday. Any changes with the track
could bring some heavier rains to the area. We have just used the
wpc probability of precipitation for now...mostly chance (thu) and slight chance (thu night).
Temperatures will return to near normal for the middle/late part
of next week.

&&

Aviation /14z Saturday through Wednesday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg,
kilg, kmiv, kacy and surrounding areas.

Today...broken ceilings at or above 10000 feet developing south portion may
briefly thin late in the day. Higher thinner clouds kabe
northward.

Light west - northwest wind wind becoming west midday with gusts
to about 15 knots possible during the afternoon in New Jersey/PA but
seabreezes develop along coastal sections middle and late afternoon.

Tonight...ceilings at or above 8000 ft, especially after 03z/26. A sprinkle
possible kphl/kilg/kmiv kacy but not in the forecast at this time. It may be
too dry in the layer under 8000 feet. Light west wind shifting north-NE
during the night. Please see tafs for timing details as a wind
shift boundary sags southward.

Outlook...

Sunday...mainly VFR conditions, as any sub-VFR in rain to start
across southern areas will improve back to VFR.

Monday...mainly VFR conditions; although, some isolated showers are
possible. Gusty north to northwest winds, with gusts to 20 knots.

Tuesday and Wednesday...mainly VFR expected; although, conditions
may deteriorate late Wednesday night depending on the timing and
track of a possible coastal low pressure.

&&

Marine...
sub Small Craft Advisory conditions through tonight with northwest to north winds
backing to westerly midday then sea breezes during middle - late
afternoon. Light winds tonight becoming north-NE late.

Outlook...
Sunday/Sunday night...sub-sca conditions. Rain south.
Monday/Monday night...mostly sub-Small Craft Advisory but some wind gusts around
25 kts possible. Scattered showers. Tuesday through Wednesday...mostly sub Small Craft Advisory.

&&

Fire weather...
dry conditions are expected once again today, with minimum relative humidity
values once again ranging from 20 to 35 percent north to south.
However, winds will be considerably lighter, with gusts generally
near or below 15 miles per hour through the day. No action at this time.

&&

Phi watches/warnings/advisories...
PA...none.
New Jersey...none.
Delaware...none.
Maryland...none.
Marine...none.

&&

$$
Synopsis...O'Hara
near term...drag/Kline
short term...drag
long term...O'Hara
aviation...drag/Kline/O'Hara
marine...drag/O'Hara
fire weather...

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