FXUS61 KAKQ 231111

National Weather Service Wakefield VA
711 AM EDT Thu May 23 2019

High pressure settles off the Southeast coast today into
tonight as low pressure passes north of the region. This area of
low pressure drags a weak cold front through the area late
tonight. High pressure builds in from the northwest Friday and
then passes over the region Saturday, and then shifts off the
Southeast coast Sunday and Memorial Day.


As of 400 AM EDT Thursday...

Current GOES WV and IR imagery depict a shortwave trough with
intense convection pushing through the Midwest, with a mid/
upper level ridge centered over the Southeast coast. At the
surface, high pressure is located off the coast, with low
pressure over the Great Lakes, and a cold front trailing into
the Mississippi Valley. The mid/upper level ridge axis will push
offshore later this morning as the shortwave trough tracks
through Ern Great Lakes. Meanwhile, the low-level flow will
become SW, which will allow for slow moistening of the low-level
airmass. Much warmer high temperatures ranging from the mid 80s
to around 90F, with low 80s for much of the Ern Shore and
coastal SE VA/NE NC, and upper 70s at the immediate Atlantic
coast of the Ern Shore.

The shortwave trough is expected to trigger additional strong
to severe tstms N of the region from PA to NJ later this aftn in
a zone of 40-50kt 500mb flow and 35-45kt 700mb flow. It should
be noted that this shortwave will dampen upper ridging to a
degree,with resultant quasi-downslope flow serving to lower
areal coverage of tstms over the local area. Hence, there are
mixed solutions amongst the CAMs with respect to the srn extent
of the convection later this aftn and evening. Another factor to
consider for areal extent of convection is a rather prominent
cap ~900-850mb. SPC has maintained a marginal risk across the
nrn third of the area, with the slight risk line clipping the
Nrn Neck and MD Ern Shore. This is definitely conditional on
tstms actually reaching the area, but any tstms that do reach
the area could produce locally damaging wind gusts and large
hail. PoPs are mainly 20-30% from about 20z-04z. Drier air
arrives late as a weak cold front moves through the area. Low
temperatures late tonight range from the upper 60s to low 70s.


As of 400 AM EDT Thursday...

The airmass behind the front Friday will still be rather warm
as high temperatures range from the low 80s over the Ern Shore
(upper 70s immediate Atlantic coast), to the upper 80s/low 90s
for much of the area with downsloping deep layer NW flow. Drier
behind the front Friday, especially N where aftn dewpoints drop
into the low/mid 50s. The 23/00z NAM brings some upper energy
through the area within the NW flow. However, a dry forecast has
been maintained given limited moisture.

23/00z numerical guidance depicts somewhat of a reprieve from
the anomalous heat Saturday as high pressure passes across the
region resulting in E-SE low-level flow along the coast, and
SE-S flow farther inland. Forecast highs Saturday range from the
low/mid 70s E (cooler along the immediate Atlantic coast of the
Ern Shore) to the low/mid 80s farther inland, after morning
lows in the upper 50s to mid 60s. By Saturday evening, there is
a slight chc of showers/tstms drifting off the higher terrain
into the Piedmont.

Sunday has the potential to be the hottest day of the Spring
thus far. Surface high pressure slides well off the Southeast
coast as low pressure moves into the Ern Great Lakes. This will
result in WSW low-level flow, which will help boost high
temperatures into the low/mid 90s inland, with upper 80s over
the Ern Shore, and even mid 80s at the immediate Atlantic coast.
Lows Sunday morning range from the mid 60s to around 70F.


As of 250 PM EDT Wednesday...

Summerlike/temperatures remaining above normal through the extended
forecast period. An upper level anticyclone remains centered along
the Gulf Coast early next week, putting our region in W-NW flow
aloft. Meanwhile, an anomalous deep trough aloft will continue
to largely remain out over the wrn CONUS. A weak frontal
boundary crosses the area Sun evening-Sun night, but only
isolated tstms are expected (mainly N/NE). Isolated-scattered
aftn/evening tstms are possible on Mon, but the chance of this
is only ~20%. Drying out from Tue-Wed as upper ridging amplifies
over the US East Coast as the aforementioned deep trough aloft
ejects out into the nrn Plains.

Lows Sun night in the u60s-around 70F. Highs Mon in the 80s over the
lower Ern Shore to the low 90s inland. Highs Tue from the low 80s
over the Ern Shore to near 90F inland. Forecast highs on Wed are in
the low 90s in most areas, but there is the potential for it to be
even warmer.


As of 710 AM EDT Thursday...

High pressure is centered off the Mid-Atlantic coast as of 11z.
The wind is 5-8kt out of the S under with BKN cigs ~5kft over SE
VA/NE NC. These clouds should dissipate and move offshore later
this morning. Surface high pressure will push farther offshore
today with the wind becoming SW, and increasing to 10-12kt with
gusts up to 20kt by this aftn. SCT CU are expected to develop
by this aftn, with a 20-30% chc of showers/tstms (primarily from
RIC- SBY and N) after 20z and continuing through 04z Friday as
a trough pushes across the region in NW flow aloft. Tstms could
produce locally stronger wind gusts along with reduced vsby in
brief heavy rain.

Mainly dry conditions are expected Friday through the weekend
and into Memorial Day as weak high pressure prevails over the
region. There is a low probability of showers/tstms Sunday
night along and N of a line from RIC-SBY.


As of 420 AM EDT Thursday...

High pressure will slide farther into the Atlc during today.
A weak cold front approaches from the northwest late today, then
drops acrs the area tonight into Fri morning. Early this
morning, winds were SSE 5-15 kt over the waters, with waves 1-2
ft and seas 2-3 ft. As the cold front approaches from the
northwest, SSW winds will increase to 10-20 kt, with a few gusts
up to 25 kt over the nrn coastal zns, this aftn into tonight.
These winds will also build seas to 4-5 ft over the two nrn
coastal zns, so have hoisted a SCA for 650-652 fm 7 pm this
evening to 7 am Fri morning. Farther south, winds will be
between 15-20 kt with seas 3-4 ft. In the Ches Bay and rivers,
SSW winds this aftn into tonight will be 10-15 kt and waves
will be around 1-2 ft.

Behind the cold front on Fri, high pressure will build back
into the area for the holiday weekend. Looks like winds and seas
will stay below SCA criteria through Mon.


* Avg Date of 1st 90F (1981-2010 Climatology):

* Site Avg 2019 Value

* Richmond: May 13th (Sun 5/19)
* Norfolk: May 16th (Sun 5/19)
* Salisbury: May 27th (none so far)
* Eliz City: May 18th (Sat 5/18)

* Number of Days of 90F+ in May:

* Site Avg Most

* Richmond: 2 days 11 days (1962)
* Norfolk: 2 days 13 days (1880)
* Salisbury: 1 day 7 days (1991)
* Eliz City: 2 days 9 days (1944 & 1941)


As of 420 AM EDT Thursday...

KAKQ 88D radar out of service until further notice. Techs are awaiting
parts to make needed repair. Return to service possible later today
or Fri.


MARINE...Small Craft Advisory from 7 PM this evening to 7 AM EDT Friday
for ANZ650-652.


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