Area Forecast Discussion
Issued by NWS Wakefield, VA

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864
FXUS61 KAKQ 281059
AFDAKQ

Area Forecast Discussion
National Weather Service WAKEFIELD VA
659 AM EDT Tue Mar 28 2017

.SYNOPSIS...
A cold front approaches from the west today and crosses the
region late this afternoon and tonight. High pressure builds in
from the north on Wednesday. The high retreats to the northeast
on Thursday as the next system approaches from the west. A
strong system is expected to impact the region on Friday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Watching low pressure and its attendant cold front move across
the OH/TN Valleys early this morning. At the same time upper
level ridging has begun to break down across the local area in
advance of this system, allowing scattered showers and isolated
tstms to develop just to our west. As the upper level trough
continues to push into the area today, will see an increase in
pops during the morning into the afternoon hours. Have highest
pops 30-50% limited to our Piedmont counties through 12z, then
higher pops 40-60% spreading across the remainder of the FA thru
18z. Current thinking is that there will be an initial area of
showers and embedded tstms that move thru the area from west to
east between 12-17z, then a secondary batch of shwrs/tstms that
moves thru between 18-23z. SPC has the area highlighted in a
marginal risk for severe storms this aftn/eve due to increased
shear and sfc dew pts near 60F. Think the severe threat will be
low this afternoon due to only a small window of opportunity
for the atmosphere to recover after the morning pcpn exits. It
will remain mild today despite plenty of clouds. Highs in the
low to mid 70s, except cooler 60s at the beaches.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
Will limit chance PoPs to areas along/east of I-95 by late this
evening as the Piedmont dries out, then drying out all the way
to the coast after midnight with lows mainly 50-55 F (except upr
40s ern shore). Becoming partly/mostly sunny Wed after some
early clouds (especially south) as drier air moves in from the
N. Somewhat cooler but still a little above avg with highs
60-65F near the coast and in the upper 60s to lower 70s well
inland. Upper ridge axis quickly moves back into the region by
Thu, allowing return of mid/high clouds during the day. With
fairly low mixing and overrunning clouds, expect a cooler day
with highs mainly ranging from the mid 50s to around 60. Kept it
dry through the day despite the increase in clouds ahead of the
next system.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
A complex low pressure system approaches from the west late Thu
night and early Fri before slowly crossing the region
Friday/Friday night. Guidance in good agreement with respect to
potential for widespread showers/tstms and potential for heavy
rain during Fri. Will limit pops to 20-30% along west of I-95
prior to 12z Fri before increasing to 60-80% all areas during
Fri (highest west). Will keep similar pops Fri night with a slow
exit of pcpn expected. Dry wx and high pressure returns for Sat
aftn thru Sun night. Yet another system may approach fm the
west late Mon.

Highs in the upper 50s to upper 60s Fri, in the 60s to near 70
Sat, in the mid 60s to lower 70s Sun, and in the 60s to near 70
Mon. Lows in the 40s Thu night, in the upper 40s to mid 50s Fri
night, in the 40s Sat night, and in the mid 40s to near 50 Sun
night.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Scattered showers and thunderstorms will be possible throughout
the day today, with the potential for a few storms to be strong
late this afternoon and early evening. Brief sub-VFR CIGS/VSBYS
will be possible in the heaviest showers/storms. Winds will
remain S-SW around 10 kt.

Outlook: Unsettled weather conditions will continue thru
Tuesday evening due to the potential for showers and
thunderstorms. Dry/VFR conditions return on Wednesday as winds
shift to the north. The next storm system is expected to
approach the area Friday bringing the next chance of adverse
aviation conditions.

&&

.MARINE...
Latest obs reflect SSW flow across the waters. Surface high pressure
continues to linger along and just offshore of the Mid-Atlantic and
Southeast coast this morning, as a cold front approaches from the
Ohio and Tennessee River Valleys. Pressure gradient will gradually
tighten today, allowing gradual increase in winds this afternoon and
tonight...before the front crosses the waters late this evening and
overnight. SSW winds become NNW post frontal late tonight and
continue through Wed, as high pressure starts to build in fm the N.
While experimental wind probs are indicating a small chance for a
few gusts to low end SCA in the Ches Bay Wednesday morning through
midday, still do not expect predominate SCA conditions to be met
thru Wed. However, winds will be marginal for much of the
morning and early afternoon in the lower Chesapeake Bay and
Currituck Sound, and will need to watch marginal SCA gusts
during that time. Will also need to watch encroaching SSE swell
on Wednesday, owing to developing system crossing south of
Bermuda this morning. NWPS and WaveWatch in general agreement
in depiction 5 ft seas mainly south of hatteras and offshore of
the Mid-Atlantic waters, and thinking at this time is much of
this energy stays well offshore. Thus, will hold Significant
wave heights at 3 to 4 ft, just below SCA thresholds. Waves 1-2
ft today...building to 2-3 ft on Wed.

Otherwise, cool high pressure will continue to build in from the
north Wed night into Thu morning, before it slides out to sea Thu
aftn and night. NNE winds 10-15 kt Wed night and early Thursday,
become NE 5 to 10 kt by Thu aftn. E-NE winds 5 to 10 kt Thu night
become SE 10-15 kt by Friday morning, and southerly by afternoon as
a warm front lifts across the waters. Seas subside during this
period of diminishing winds Wed-Thu, but increase again Friday
afternoon and evening ahead of next cold front, which crosses the
waters Saturday morning. Seas build back to 4-5 ft, highest toward
outer waters in pre-frontal south flow. A brief period of SCA
headlines is possible over the coastal zones, mainly for seas. Seas
subside back into the 2-4ft range over the weekend in NNW flow aob
15kt as surface high pressure rebuilds over the waters.

&&

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

&&

$$
SYNOPSIS...JDM
NEAR TERM...JDM
SHORT TERM...JDM/LKB
LONG TERM...TMG
AVIATION...JDM
MARINE...MAM



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