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Area forecast discussion 
National Weather Service Wakefield Virginia
633 am EDT sun Jul 24 2016

Synopsis...
high pressure prevails over the region through Tuesday. A weak cold
front drops into the region Tuesday night into Wednesday.

&&

Near term /until 6 PM this evening/...
ltst msas showing high pres across the region with a trof extending
along a phl-roa-avl line. The high pres continues the mid Summer
heatwave. Challenge of the day will be temps/dp temps and resultant
heat index values as the trof meanders east of the mts. 850 mb tmps
remain in the 20-22c range (+2 std dev). Given plenty of sunshine,
sfc tmps should easily reach the mid-upr 90s across the fa except
upr 80s-lwr 90s at the beaches. Airmass is mostly capped once again,
keeping the threat of any convection low. Models do hint at the
potential for an isltd tstm to develop along a sea breeze bndry
across the ern shore / wrn fringes of the ches Bay this aftrn, but
capped pops at 14% as confidence is low that this will occur.

Location of sfc trof this aftrn will be critical as to where dew pt
temps can mix out to arnd 70. East of there expect dew pt tmps to
remain in the low to mid 70s, resulting in heat index values aoa
105. Latest data suggests only then nwrn counties along with the
ern shore areas (due to sea breezes) stay aob 104. Thus, have
elected to expand heat advsry frthr west and north a bit. Will
have 2 segments, the additional counties for heat index values
around 105 with the original advsry btwn 105-110.

&&

Short term /6 PM this evening through Tuesday/...
warm and humid tonight with lows in the mid to upr 70s. Hottest day
of this stretch appears to be on Mon with highs in the mid-upr 90s
again, except upr 80s-lwr 90s at the beaches. Not out of the qstn
to see an AWOS record 100. Dew pt temps progged to be in the low-
mid 70s fa wide. This would agrue for most if not the entire fa in
a heat advsry. Only chc for isltd tstms is over the nwrn zones,
all depending on how far east any tstm off the mts can move.

The upper ridge begins to slowly break down Mon night into tues as a
frontal boundary slowly approaches from the west. Remaining warm and
humid Mon night with evening convection limited to the northern most
zones. Lows in the low-mid 70s. Continued hot Tuesday with highs in
the mid 90s. Dew pts remain in the low-mid 70s resulting in heat index
values aoa 105 most areas (heat advsry range). There is a 20-40% chc
of afternoon tstms west of the ches Bay after 18z.

&&

Long term /Tuesday night through Saturday/...
stacked high pressure over the southeast coast allows zonal/westerly
flow aloft to settle across the region Tuesday night through the
week. A series of wx disturbances will pass across the region and
keep a chance for thunderstorms in the forecast each aftn/evening.
Pwats around 2.00-2.25 inches and dewpoints in the low-mid 70s
will result in muggy conditions with ample moisture present across
the area...making strong gusty winds and locally heavy rainfall
the anticipated impacts from thunderstorms. Combine the humidity
with temperatures remaining in the low 90s, and heat indices will
continue to run around 100-104 degrees with a few pockets in far
southeast Virginia/NE NC reaching 105-106 degrees for an hour or two each aftn.
Lows generally in the low-mid 70s inland and mid-upper 70s beaches
each night.

&&

Aviation /10z Sunday through Thursday/...
12z taf period starts off with VFR conditions and light winds over
all terminals. Expect winds to avg out of the S/SW this aftn at
5-8 kt with mainly just some passing hi clouds. No chance of rain
thru the taf period.

Outlook...another mainly dry day is expected Monday. A cold front
drops into the area Tuesday/Wednesday bringing isolated-scattered
showers/tstms both days...primarily during the afternoon/evening
hours. Brief reductions in visibilities and ceilings to MVFR/IFR levels are
possible with the storms.

&&

Marine...
benign marine conditions expected this week with no headlines
necessary. Expect a fairly stagnant wx pattern today into Mon with
hi pressure centered off the se coast and weak trofs of lo
pressure over the mid Atlc. Winds will avg 10-15 kt out of the
S/SW thru this period with 1-2 ft waves over the Bay and 2-3 ft
seas over cstl wtrs. There may be a surge in winds to 15 kt
Bay/sound and 15-20 kt coastal waters Monday night ahead of the
next cold front. This front drops into the area late Tue/Tue
night, and remains in the vicinity thru the end of the week.

&&

Climate...
while its certainly going to be hot today thru Mon, climatologically
this is the hottest time of the year with several heat waves having
occurred in the past that have been far more intense than what we
will experience. Record highs are unlikely to be set sun/Mon, and in most
cases, don't expect that they will even challenged within 5 deg f.

* Record highs:

Records sun (7/24) Mon (7/25)

* ric: 105 (2010) 105 (2010)
* orf: 105 (2010) 105 (2010)
* sby: 101 (2010) 100 (2010)
* ecg: 97 (2012) 99 (1949)

&&

Akq watches/warnings/advisories...
Maryland...none.
NC...heat advisory from 11 am this morning to 8 PM EDT this evening
for ncz012>017-030>032.
Virginia...heat advisory from 11 am this morning to 8 PM EDT this evening
for vaz065>068-077>090-092-093-095>098-513>516-518-520-
523>525.
Marine...none.

&&

$$
Synopsis...mpr
near term...mpr
short term...mpr
long term...bmd
aviation...mas
marine...mas
climate...

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