Area Forecast Discussion
Issued by NWS Wakefield, VA-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KAKQ 180320
Area Forecast Discussion
National Weather Service Wakefield VA
1020 PM EST Fri Feb 17 2017
-- Changed Discussion --High pressure slides offshore of the Southeast coast overnight
into Saturday. A weak area of low pressure moves through the
Carolinas Saturday night with high pressure returning by Sunday
afternoon. A backdoor cold front pushes through the Eastern
Shore Sunday night, as high pressure builds well north of the
-- End Changed Discussion --
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
-- Changed Discussion --Late this evening, high pressure was cntrd right along the nrn
Fl coast. Also, a srn stream trough was over TX/LA. The high
will slide farther off the SE coast overnight into Sat morning
providing a clear to partly cloudy sky, as just some high clouds
affect the NE counties and SW counties. Lows will range fm the
lower 30s to the lower 40s.
-- End Changed Discussion --
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
Mid-level ridging builds into the Mid-Atlantic by
Saturday. Temperatures will continue to moderate with highs rising
into the upper 60s to low 70s (upper 50s/low 60s at the immediate
Atlantic coast of the Ern Shore). Mid/high clouds increase Saturday
aftn as a srn stream system pushes into the Tennessee Valley. The
upper system dampens as it lifts into the central Appalachians
Saturday night with the energy shifting off the Southeast coast.
Trended PoPs downward to only ~20% across the Piedmont and central
VA, and the Currituck Outer Banks.
This system ambles offshore Sunday as weak high pressure builds in
from the west. Above normal temperatures continue with decreasing
clouds. Morning lows range from the mid 40s to around 50, followed
by highs in the upper 60s to low 70s west of the Bay (again locally
cooler at the coast).
High pressure builds into the Ern Great Lakes Sunday night and
pushes a backdoor cold front through the Ern Shore. This high (1030+
mb) will continue to build ewd Monday resulting in onshore flow
along the coast, which will result in cooler (but still above
normal) temperatures along the coast, while the Piedmont will remain
mild. Lows Sunday night/Monday morning average in the low/mid 40s.
Forecast highs range from the low/mid 50s for the Ern Shore, to the
low/mid 60s in the I-95 corridor, to the upper 60s/near 70 over the
Piedmont. Mostly clear/sunny Sunday night into Monday.
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
High pressure will settle over the region Mon night through Tue and
then slide off the Mid Atlantic Coast Tue night into Wed. After
that, the area sits right smack in the middle of split flow with
active systems passing well north and well south...and primarily
westerly flow aloft. This is not a good set-up for active weather
within the long term forecast periods. 12Z GFS now trying to depict
one long, elongated trough passing through the region on Wed and
bringing precip to the area. This is a new solution and does not
seem to hold much merit to what should happen in reality. The 12Z
ECMWF is also trying to bring weakening shortwave energy and light
precip across the area as well. Leaned more towards a WPC solution
regarding POPs and then dropped everything by 5 percent. This ends
up keeping a slight chance for rain showers late Tue night into
Wed. Will see how this pans out against new 18/1200Z data.
Otherwise, expect a generally dry forecast with temperatures running
anywhere from 10-20 degrees above seasonal normals.
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
High confidence that VFR conditions will continue through the TAF
period. Mainly clear skies are expected to persist tonight with
only the potential for a few higher clouds. Mid/high clouds
will increase towards the end of the forecast period as an upper
trough lifts into the Tennessee Valley. Winds generally remain
light and variable tonight and increase to SW 5-10 knots during
the day on Saturday.
Outlook: An upper level trough will push into the central
Appalachians Saturday night, with weak low pressure reorganizing
off the Southeast coast. The primary forcing will split the area
with only a 20% chance of spotty light rain. High pressure
returns later Sunday which will allow for dry and VFR conditions
to continue into early next week. A weak cold front will cross
the region Wednesday with only a minimal chance of light rain.
Light and variable winds around 10kt or less the rest of today with
seas of 2-3ft and waves 1-2ft. Sfc high pressure east of FL will
result in winds becoming more sly this evening and increase to
10-15kt. Winds then become southwest overnight through Sat night
with speeds remaining aob 15kt during this time. Seas will continue
to average 2-3ft; waves 1-2ft. A weakening upper level low passes
south of the area Sat night into Sun as a very weak trough develops
off the Carolina and Southeast coasts. Main impact to waters will
be a wind shift to w-nw in this timeframe with speeds remaining
aob 15kt. High pressure will then settle over the waters Mon through
Tue and then slide off the Mid Atlantic Coast Tue night into Wed.
Winds become more n-ne Mon through Tue...swinging around to the sw
by Wed. Speeds continue to average aob 15kt, seas 2-3ft, and waves
Very warm once again for the weekend, currently not expecting
to set record highs but it may be close so for reference the
record highs are listed below:
* Site Sat 2/18 Sun 2/19
* RIC: 77 (2011) 78 (1961)
* ORF: 77 (1937) 73 (1907)
* SBY: 75 (1976) 72 (1961)
* ECG: 80 (1976) 77 (1939)