Portsmouth, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

045
FXUS61 KAKQ 070705
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
305 AM EDT Sat Jun 7 2025

.SYNOPSIS...
A cold front moves into the region today, before lingering over
the area Sunday. Afternoon and evening showers and storms are
expected both today and Sunday, with severe weather possible.
Drier weather returns on Monday, with increasing storm chances
again on Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 300 AM EDT Saturday...

Key Message:

- Scattered to numerous thunderstorms are expected this afternoon/evening.
  The highest coverage of storms, and the greatest SVR
  potential will be across the southern 1/2 of the area.

Early morning wx analysis shows a cold front draped over the
northern Mid-Atlantic, and the progressive pattern aloft remains in
place with fast zonal flow over the eastern CONUS. A shortwave is
quickly approaching, and will slide across the region later this
morning. Still seeing some isolated showers over the area with
mild/humid wx in place. The cold front approaches from the NNW later
today and this (along with a prefrontal trough) will serve as a
trigger for convective initiation. No more than scattered
showers/isolated tstms are expected through early aftn. While
there are some questions regarding sfc heating farther north,
temps should rise well into the 80s-near 90F south of a FVX-PTB
line with upper 60s- 70F dew pts area-wide. This will allow for
ample instability (1000- 1500 J/kg MLCAPE) along and south of
I-64 despite meager mid-level lapse rates (5.5 to 6C/km), while
modest height falls and the approaching cold front provide the
necessary lift for convection to develop by 2-3 PM. Initial
development will likely be across central/eastern VA. Then,
there is very good agreement in the 00z/07 CAMs that tstms
increase in coverage as they move to the SE during the late
aftn/evening before exiting the area late in the
evening/overnight. Unsure how much in the way of storms form
across northern areas (from LKU-SBY) where sfc heating won`t be
as strong. But, now have high confidence in at least scattered
tstms along and south of I-64. One factor that could suppress
convection today is if morning clouds/showers linger long enough
to impact convective initiation during the aftn/evening. With
the instability in place combined with 30-40 kt of effective
shear, strong to severe tstms are possible. The highest threat
is south of I-64 where SPC has a Slight Risk (Level 2/5) for
severe wx, while the Marginal Risk has been maintained farther
N. Still looks like primarily a damaging wind threat with storm
mode likely becoming linear...although the initial cells may be
able to produce small hail (not as confident in large hail given
high freezing levels and only 5.5 to 6C/km mid- level lapse
rates). In addition to the severe threat, localized urban/poor
drainage flooding cannot be ruled out across SE VA/NE NC. PWs
will be near 2" and despite the relatively fast storm
motions/dry antecedent conditions...a quick 2-3" would cause
some issues. Given the agreement in the CAMs, the 00z/07 HREF as
10%+ probs of 3" in 3 hours across our SE zones. As such, WPC
has introduced a MRGL Risk for Excessive Rainfall in these
areas.

Showers/tstms should temporarily exit after 10 PM or so, but another
shortwave in the fast zonal flow aloft (along with an associated sfc
low) begin to approach Sunday AM. The approaching sfc low will allow
the front to start moving back north as a warm front...and despite
the unfavorable timing in the diurnal cycle...we could see scattered
showers and isolated tstms develop as the front moves back north
through part of the CWA (mainly between 4-10 AM). Lows tonight will
mainly be in the mid 60s to around 70F.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
As of 300 AM EDT Saturday...

Key Messages:

- Scattered to numerous thunderstorms are expected again Sunday  as
  a frontal boundary lingers across the region.

- A few of the storms may be strong to severe, with damaging
  wind gusts being the main threat. A brief tornado can`t
  completely be ruled out near the front.

The front continues to move north on Sunday before stalling as
secondary low pressure develops and tracks from W-E along it. The
position of the front Sunday afternoon will dictate where the
highest severe threat is as another robust shortwave aloft is
progged to quickly cross the region during the aftn-evening. A few
showers (with perhaps a rumble of thunder) are possible Sunday
morning, with scattered-numerous tstms expected once again during
the aftn/evening. Similar to Saturday, the main focus for severe wx
will be along and south of that front. Models differ on how far
north the front makes it, with the NAM and some of the CAMs showing
it from FVX-RIC-JGG during the aftn, while the HRRR and a few other
CAMs are farther north and shows the front making it to northern
portions of the CWA. Regardless, it appears as if the most likely
timing for severe wx is from 2-10 PM Sunday. Instability/deep
shear parameters on Sunday look to be roughly similar to what
they will be today. Damaging wind gusts will be the main threat,
but large hail can`t completely be ruled out, given somewhat
more favorable mid level lapse rates (potentially 6 to 6.5
C/Km). Lastly, there is a low but non-zero tornado threat near
the front where winds will be locally backed and more out of the
SE. SPC has expanded the SLGT (Level 2/5) Risk to include the
entire area on Sunday. There will also be the potential for
locally heavy rainfall/localized flooding given PWATs remaining
elevated and with the front nearly parallel to the mid level
flow. Precip quickly exits after 10-11 PM Sun night once again
with lows falling into the mid-upper 60s.

By Monday, PW anomalies return to near normal with the front washing
out across NC, so PoPs are mainly 20% or less, with the exception of
20-30% near the Albemarle Sound.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 300 AM EDT Saturday...

Key Message:

- Unsettled conditions return Tuesday, with mostly dry weather
  expected by Wednesday/Thursday.

Scattered-numerous aftn/evening tstms are once again expected on
Tuesday as moisture increases ahead of another (fairly strong)
shortwave trough pushing through the lower Great Lakes. There will
likely at least some sort of organized severe threat given that the
mid-level flow will be 30-45 kt with a decent amount of instability
to work with. By Wednesday, high pressure and drier conditions
potentially return to the region as the trough axis moves offshore.
Dry wx continues on Thu, with isolated aftn/evening convection
potentially returning on Fri. Temperatures will be near normal Tue,
then trending above normal later in the week with highs into the
upper 80s to lower 90s.

&&

.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
As of 150 AM EDT Saturday...

Lingering showers are diminishing across the region early this
morning. Patchy MVFR conditions are noted in areas that received
showers and storms on Friday. SBY and vicinity is seeing more
widespread IFR conditions. Brief departures into LIFR are
possible in these areas through roughly 12z. IFR/MVFR conditions
will linger into mid morning for the MD Eastern Shore. Generally
VFR this afternoon at all sites with potential for widespread
showers and storms after 20z (later along the coast) as a weak
front approaches the area. Low confidence in timing and
placement of convection precludes anything more than PROB30
mention at this time.

This front is expected to linger in vicinity of the region Sunday
with a high chance of showers/tstms continuing. The latest guidance
shows the front pushing S of the region Monday. Showers/storms
return Tuesday aftn/evening, then a bit drier again Wednesday.

&&

.MARINE...
As of 300 AM EDT Saturday...

Key Messages:

- Sub-Small Craft Advisory conditions are expected through the
  weekend.

- Potential for scattered strong thunderstorms across the waters
  late this afternoon into the evening and again on Sunday.

Weak low pressure is noted off the MD coast. Winds are very light
across the waters with most observations showing less than 5 kts.
Waves are around 1 foot with seas 2-4 ft.

Guidance suggests swell energy will propagate toward shore early
this morning through sunrise or so before decreasing this afternoon.
Undercut the wave guidance as it was showing 4-6 ft seas across the
northern coastal waters by 3am. Otherwise expecting generally light
flow through early afternoon before winds turn onshore late this
afternoon into the evening at 5-10 kt. A prefrontal trough will help
to initiate showers and storms over inland areas this afternoon,
moving toward the coast this evening. A few of these could be
locally strong to severe with gusts 35-50 kt possible. The southern
Chesapeake Bay and coastal waters have somewhat higher chances
strong storms this evening vs points to the north. Sub-SCA
conditions continue tonight (outside of any thunderstorm
influences). Onshore flow develops again by Sunday afternoon with
greater coverage of showers and storms expected area wide from late
afternoon into the early overnight hours. Strong winds will be the
main threat once again on Sunday. An area of low pressure
potentially forms along the front early next week (late Monday into
Tuesday) which could allow the front to drop south of the waters by
mid week.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.

&&

$$

SYNOPSIS...ERI/LKB
NEAR TERM...ERI
SHORT TERM...ERI/LKB
LONG TERM...ERI/LKB
AVIATION...RHR/NB
MARINE...RHR