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Area forecast discussion 
National Weather Service Mount Holly New Jersey
845 PM EDT Sat may 23 2015

Synopsis...
strong high pressure will slide offshore tonight and remain centered
to our east through the week. A warm front will move northward
through our area on Monday, bringing hot and humid air to the
region. A cold front will approach from the west around midweek,
dissipating as it moves eastward. A stronger system will approach the
region toward next weekend.

&&

Near term /until 6 am Sunday morning/...
earlier forecast working out well with few changes needed to the forecast.

High pressure will continue to build offshore tonight. This will
allow return flow to develop, which will allow moisture and
temperatures to increase a little. Tonight will not be as cool as
last night, but we are still expected to be below normal. Even
though moisture increases as dewpoints rise, the forecast is
precipitation free as there will be little if any cloud cover.

&&

Short term /6 am Sunday morning through 6 PM Sunday/...
high pressure will remain off the East Coast Sunday, keeping the
return flow across the area. Temperatures will rise much warmer than
Saturday, and should rise close to or above normal. Although there
will be an increase in clouds through the day, mainly middle/high level
clouds, the forecast will remain precipitation free.

&&

Long term /Sunday night through Saturday/...
surface high pressure will remain offshore and east of the area. A
middle level ridge will build over the region and persist through the
week. A cold front will approach from the west around midweek but
may take several days to push closer to the area due to the strong
ridging over the region. A stronger system approaches towards next
weekend.

Overall, we should see a fairly dry week across the region. There
remains the chance for some showers and thunderstorms through the
week as we see increasing moisture along with a warming trend in the
south to southwest flow.

Sunday night through Memorial Day...skies may be cloudy overnight in
the increasing south to southwest flow but should start to clear
during the day on Monday. Overall a fairly nice day to end the
Holiday weekend. A warm front located to the north and west of the
region may be close enough to trigger a few showers across the
northwestern zones during the afternoon. However, confidence is not
high that these will occur and we have kept the forecast dry.

Tuesday...a couple of low pressure systems will move well to the
northwest of our area. With the middle level ridge holding strong, we
should remain mostly dry across the area. A few
showers/thunderstorms may develop across the northwestern areas late
in the day. Temperatures will start to increase and be well into the
80s, especially inland and near urban areas.

Wednesday...the atmosphere will continue to destabilize as more
moist and hot air moves into the region. Conditions will become
increasingly more humid and temperatures will approach and/or exceed
90. Heat index values will make it feel even hotter and we will need
to monitor the need for heat headlines. With the unstable air
around, we will have better chances for showers and thunderstorms.
Hot and humid day will give way to a sticky kind of night across our
region.

Thursday and Friday...the ridge starts to weaken and push eastward
which will allow for an approaching cold front to start pushing into
the area. Continued chances for showers and thunderstorms as we
continue to have hot and humid air residing over the region. Plenty
of available moisture which indicates that developing storms will be
efficient rainmakers. Another sticky night on tap as we wont see
much cooling if the front is unable to make it across the area.

As we head into next weekend, another frontal system will approach
the area. This storm looks to be a bit more robust and could
potentially bring some much needed rain to our area.

&&

Aviation /01z Sunday through Thursday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.

VFR conditions remain across the taf sites through Sunday. Winds
become more southwesterly tonight and remain generally southwest
through Sunday. There could be a few gusts around 15 knots as well
during the day Sunday.

Outlook...
Sunday night through Monday...VFR conditions expected. South to
southwest winds around 10 knots. Some gusts up to 20 knots during
the afternoon.

Tuesday through Thursday...mainly VFR conditions expected. South to
southwest winds around 10 knots with gusts up to 20 knots during the
afternoon each day. Reduced ceilings/visibilities in any showers and
thunderstorms that may develop.

&&

Marine...
conditions are expected to remain below Small Craft Advisory
conditions through Sunday. High pressure builds off the East Coast
tonight, bringing southwest winds to the waters. Winds could gust
around 20 knots at times, especially Sunday.

Outlook...
Sunday night through Thursday...sub-advisory conditions expected to
continue on the area waters. Winds will be primarily out of a south
or southwest direction with speeds around 10 to 15 knots. Winds may
gust around 20 knots but should remain below Small Craft Advisory
criteria. Seas around 2 to 4 feet.

&&

Rip currents...
potential heat wave next week. This plus water temperatures continuing above
normal is not good for safety. Once it turns hot and beaches are
unguarded, swimmers may take chances at unguarded locations. Be smart
about any swimming early this season.

Rip current awareness week for Montana Holly is June 7-13 with psas
via public information statements, social media, National oceanic and atmospheric administration weather
radio and any media interviews desired (contact office).

For rip currents: despite anticipated projections of low or
moderate risk through the Memorial Day weekend, early season
fatalities occur when swimming at unguarded times/locations.
Weaker swimmers or swimming in areas where rip currents are
stronger (jetties) can quickly become life threatening. When
trained lifeguards are not nearby, timely Rescue is much less
likely. Lets get through the month of may with all swimmers safe!

Please broadcast this message: for ultimate safety, always swim
in the presence of life guards! Thank you!

&&

Climate...
**a top 10 warmest may will occur in large portions of our forecast
area and lessening doubt for a top 3 warmest kabe/kphl**

The first 22 days of may in our forecast area were averaging
about 5 to 6 degrees above normal.

Running the numbers from the forecast through the end of the month we
find the following.

For Philadelphia...period of record (por) back to 1874.
Projecting a monthly average temperature of 69 to 70, at least 5
to 6 degrees above normal. Heading for second or third warmest on
record. Warmest was 70.8 in 1991. Then 69.2 2004.

For Allentown...period of record (por) back to 1922. Projecting
66.5 or about 6.5 degrees above normal which would be 2nd or 3rd
warmest on record. 1991 was the warmest with 67.2, followed by
2012 66.1, then 1944 when may averaged 66.0.

The following was posted because its likely that we will
experience our first 90 in Philadelphia by the middle of next
week, and possibly a heat wave.

Normal first date of 90 or higher.

Philadelphia may 29
Allentown may 30
Wilmington June 4
Atlantic City June 11.

&&

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

&&

$$
Synopsis...meola
near term...Robertson
short term...Robertson
long term...meola
aviation...Robertson/meola
marine...Robertson/meola
rip currents...
climate...

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