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000
FXUS61 KAKQ 201028
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
628 AM EDT Sat Jul 20 2019

.SYNOPSIS...
High pressure remains off the Southeast coast through Monday. A
cold front crosses the area Monday night, ending the current
heat wave by Tuesday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 245 AM EDT Saturday...

Heatwave rolls on today. Strong ridge aloft remains in control
INVOF the FA limiting any significant clouds and putting a cap
on convective potential. The challenging part of the forecast is
the dew point which models using have difficult time resolving.
Mixing will remain limited again today...though some guidance
does suggest that dew points...esp W of I 95 do lower a bit this
afternoon around peak heating which would limit HI to blo 110
degs F. Otw...expecting HI to top out between 110-115 deg F as
high temperatures reach 95-100F. Keeping Excessive Heat Warning
for all areas today (ongoing over the SE...starting at 15Z/20
elsewhere). One or two stray tstms may pop later today...some
near term hi res guidance does suggest the potential for that N
and NW of RIC and along the SSW rim of the FA after 21Z/20.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
As of 305 AM EDT Saturday...

Ridge aloft remains strong enough through Sun to keep the heat
going and limit any convective potential. After another
very warm/humid night tonight (HI likely doesn`t fall blo 85F in
many urban areas)...very hot/humid conditions expected again
Sun. There is the hint of a weak trough just W of the FA (over
the higher terrain) Sun afternoon/evening which may be enough
for ISOLD-SCT tstms there. Elsewhere...PoPs to remain blo 15%.
Heat warning headline will remain up tonight through Sun evening
all areas.

Still very warm/humid Sun night. PoPs mainly aob 15%. Ridge
aloft breaks down Mon and a cold front approaches from the NW.
Another hot day...though the heat will likely be trimmed over
NW portions. Highs NW in the l90s...while another day of m-u90s
likely central and E. A heat advisory will likely be needed E
and SE portions though there will likely a bit of SW (to 15
mph) which may help mix out/lower dew points at least a little
bit. PoPs increase to 30-50% NW and 15-25% SE by late Mon
afternoon/evening...though some of the model guidance is now
about 6 hours slower w/ the arrival of the cold front`s
influence.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 330 PM EDT Friday...

Guidance continues to suggest a fairly abrupt cool down by Tuesday
as a long wave trough sets up across the eastern half of the
country. At the surface, low pressure is progged to track from PA to
the Canadian Maritimes. Guidance has trended slightly slower w/ the
passage of the associated cold front...it is now forecast to
approach the region Monday night before slowly crossing the area
(from NW-SE) on Tue. Tstm chances increase from NW to SE Mon night-
Tue as the front slowly crosses the region. The best chc of tstms
Mon night will be across the nrn half of the CWA. As the front
approaches SE VA/NE NC Tue aftn, expect re-development of
showers/tstms (as pcpn chances diminish across northern/western
zones). Guidance is in very good agreement with respect to numerous
shower/tstm coverage Tue aftn-evening across the SE. Have likely
PoPs across the north Mon night with chc PoPs across the south. Have
gone with PoPs of ~70% across the SE Tue aftn-evening. The best
chc for stronger storms looks to be across SE VA/NE NC Tue aftn
where the FROPA coincides w/ peak heating.

The front finally moves just SE of the CWA on Tue before slowly
pushing well S of the area by Thursday. Deep-layer moisture will be
slow to exit coastal SE VA/NE NC under moist SSW flow aloft.
Therefore, will maintain chc PoPs through late Wed across far SE
zones. Drier by late next week as high pressure tries to build in
from the north. Still cannot rule out an isolated aftn-evening
shower/tstm (especially S) through Fri. Highs generally dropping
back to the low-mid 80s for Tue and Wed, then mid-upper 80s Thu-Fri
with more sunshine. Morning lows will mainly be in the upper 60s-mid
70s on Tue before dropping into the 60s in most areas from Wed-Fri
(with forecast lows in the low 70s along the immediate coast of SE
VA/NE NC).

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
As of 625 AM EDT Saturday...

VFR conditions expected through the 12Z TAF forecast period.
FEW-SCT CU again midday/afternoon w/ mainly SSW winds blo 10 kt.
An ISOLD tstm can`t be ruled out in the aftn/early evening but
bulk of any convection expected to stay S and W of the local
area. Upper level ridge slowly breaks down late Sun-
Mon...allowing for a bit better coverage of late day/eve
convection (by Mon afternoon - as cold front approaches and
drops across the FA). High PROB for SHRAs/tstms Mon night into
Tue as that front is slow to push to the E and S.

&&

.MARINE...
As of 350 AM EDT Saturday...

No headlines in the short term today thru Sun night. Strong
high pressure at the surface and aloft over the SW Atlc was
resulting in continued SW winds 5-15 kt over the waters early
this morning. Waves were 1-2 ft in the Bay, with seas 2-3 ft.

SSW winds mainly 5-15 kt will continue over the waters today
into Mon night, as high pressure remains anchored off the SE
coast. Large scale ridging will break down late Mon/Mon night,
as a surface trough precedes an upper level disturbance across
the Great Lakes. SW winds will increase as the pressure gradient
begins to tighten Mon aftn into Mon night, generally 10-20 kt
over the waters, highest in the srn Ches Bay, Currituck Snd and
coastal waters. Waves will build to around 2 ft, while seas will
build to 3-4 ft, possibly to 4-5 ft in the nrn three coastal
zns. A cold front will then drop across the waters Tue into Tue
evening, with winds shifting to the NW or N around 10 kt or less
behind the boundary into Wed morning. A period of showers and
storms (some of which may be quite strong) will precede this
front.

&&

.CLIMATE...
Best chance for breaking records with this heatwave will be
record high mins as the airmass is very humid. Record highs and
record high mins are listed below:

* Richmond:     Record High   Record High Min

* Sat (7/20):   103/1930       78/2013
* Sun (7/21):   104/1930       77/1930
* Mon (7/22):   103/1952       79/2011

* Norfolk:      Record High   Record High Min

* Sat (7/20):   102/1942       79/1977
* Sun (7/21):   101/1926       80/1983
* Mon (7/22):   102/2011       82/2011

* Salisbury:    Record High    Record High Min

* Sat (7/20):   104/1930       83/2013
* Sun (7/21):   106/1930       77/2017
* Mon (7/22):   104/1930       80/2011

* Eliz City:    Record High    Record High Min

* Sat (7/20)    104/1942       78/2012
* Sun (7/21)    102/1987       79/1983
* Mon (7/22)    104/1952       79/2011

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...Excessive Heat Warning from 11 AM this morning to 11 PM EDT
     Sunday for MDZ021>025.
NC...Excessive Heat Warning until 11 PM EDT Sunday for NCZ012>017-
     030>032-102.
VA...Excessive Heat Warning from 11 AM this morning to 11 PM EDT
     Sunday for VAZ048-060>062-064>069-075>080-099-100-509>517-
     519-521-522.
     Excessive Heat Warning until 11 PM EDT Sunday for VAZ081>090-
     092-093-095>098-518-520-523>525.
MARINE...None.

&&

$$
SYNOPSIS...MPR
NEAR TERM...ALB
SHORT TERM...ALB
LONG TERM...ERI
AVIATION...ALB
MARINE...TMG/RHR
CLIMATE...