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Area forecast discussion 
National Weather Service Wakefield Virginia
930 PM EDT Tuesday Jul 26 2016

Synopsis...
strong high pressure will remain centered over the southeast
United States through the end of the week. A weak frontal boundary
will move south into the local area tonight, then lingers across
the region through Thursday.

&&

Near term /until 6 am Wednesday morning/...
very warm and humid conditions combined with the energy FM an
approaching frontal boundary FM the N, and other outflow
boundaries produced sctd showers and tstms acrs much of cntrl and
srn Virginia and NE NC this evening. Many tstms were producing very
heavy rain with minor flooding occurring in some locations. Sctd
showers and tstms will continue ovrngt into early Wed morning as
the frontal boundary sinks swrd into the area. Otherwise, partly
cloudy, warm and humid with lows in the mid to upr 70s.

&&

Short term /6 am Wednesday morning through Friday/...
westerly flow aloft will allow the aforementioned boundary to
stall over the local area on Wednesday. Meanwhile, strong high
pressure remains centered over the area through Friday. There will
continue to be enough instability, moisture, and weak forcing to
support scattered tstms Wed/Thu aftn/eve (30-40% pops) across the
area. Again, the threat of severe wx will remain low given weak
shear profiles but locally heavy rain is possible with pws in
excess of 2". Given the increased cloud cover Wed and slightly
lower/cooler low-level thicknesses and 850 mb temps across the
north/west, should be able to shrink the size of the heat
advisory headline to southeast Virginia and NE NC. (Similar headline may be
necessary thu). Highs reach the low to mid 90s under a partly
sunny sky.

Latest model data suggests the weak front lifts back north as a
warm front thurs night to near the Mason-Dixon line on Friday in
response to a series of weak disturbances progged to track east
along it. Lows Thu night in the mid/upr 70s. Data also shows a
lingering sfc trough in Lee of mountains. Given the available low
level moisture, expect enough instability across the region to
carry chc pops across the northern two-thirds of the area Fri aftn
(slight chc far south). Warm and humid again with highs in the low
to mid 90s (possible heat advisory southeast areas).

&&

Long term /Friday night through Tuesday/...
no major changes to the going forecast for the extended. The
westerlies generally remain north of the area through early next
week with the frontal boundary remaining just north of the area or
even over the region through the period. This frontal boundary
will allow for chances of showers and thunderstorms through the
entire forecast period...with slightly higher pops Sunday into
Sunday night as heights lower across the forecast area as a weak
upper trough passes north of the region. Will go with a dry
forecast on Tuesday as the GFS and European model (ecmwf) finally suggest the
surface front may pass south of the area as the upper trough
deepens over New England and the mid-Atlantic.

It will continue warm and humid through the extended with highs
each day in the low-mid 90s with dew points still in the low-mid
70s. Probably not quite as warm as previous days...but still
uncomfortable. Perhaps a little cooler and slightly drier on
Tuesday.

&&

Aviation /01z Wednesday through Sunday/...
as of 23z...scattered thunderstorms have been in vicinity of all the
taf sites except sby during the past couple of hours. Thunderstorms
were generally dissipating at issuance time.

A weak cold front over northern Virginia will remain over the mid
Atlantic states Wednesday. Winds will generally be light and
variable through the taf period.

Included MVFR visbilities around sunrise at ric and sby due to wet
ground and expected calm winds. More convection can be expected late
in the day on Wednesday.

Outlook...scattered mainly afternoon and evening thunderstorms can
be expected through Saturday.

&&

Marine...
generally quiet marine conditions expected through next week with
a weak front remaining just north of the area and high pressure
well offshore. Winds will generally stay less than 15 kt and seas
over the coastal waters 2 ft or less. With the chances for storms
each day...cannot rule out stronger winds in and near storms but
otherwise quiet through the weekend and even into early next week.

&&

Climate...
no records have been set so far during the current heat spell.

Records Tue (7/26)

* ric: 100 (1940) actual high 95
* orf: 100 (1940) actual high 93
* sby: 102 (1940) actual high 93
* ecg: 97 (1949) actual high 95

&&

Akq watches/warnings/advisories...
Maryland...none.
NC...heat advisory from noon to 8 PM EDT Wednesday for ncz012>017-
030>032-102.
Virginia...heat advisory from noon to 8 PM EDT Wednesday for vaz079>082-
087>090-092-093-095>098-514-523>525.
Marine...none.

&&

$$
Synopsis...jdm
near term...jdm/tmg
short term...jdm
long term...mrd
aviation...lsa
marine...mrd/lsa
climate...akq

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