Area Forecast Discussion
Issued by NWS Wakefield, VA
FXUS61 KAKQ 011614
Area Forecast Discussion
National Weather Service WAKEFIELD VA
1114 AM EST Wed Mar 1 2017
A broad southwest flow will allow for warm temperatures today,
as a strong cold front approaches from the west. The front
crosses the region tonight into early Thursday morning, with
high pressure building in from the west Thursday. A secondary
cold front moves through the area Friday. High pressure then
settles over the Mid Atlantic states Saturday.
.NEAR TERM /THROUGH TONIGHT/...
Late morning analysis indicating a strong sfc cold front over
Indiana/western KY, with a pre-frontal sfc trough along the
western slope of the Appalachians. Ongoing severe wx occurring
across Tennessee/eastern KY and much of WV. A severe Tstm Watch
has been issued for areas mainly west/northwest of the AKQ CWA
for the potential for the storms to hold together and produce
severe wx after crossing the Mtns after 18Z. Confidence that
these storms remain intact enough into AKQ CWA later this aftn
is not high given the strong SW flow in the boundary layer east
of the Mtns. IR satellite imagery overall is showing warming
cloud tops aloft as well. What will be favorable for severe wx
is the very warm temperatures and strong low level lapse rates
up to about 700 mb through the aftn. Even in the absence of any
precip, expect widespread gusts of 35-40 mph through the aftn
(with the typically windier locations gusting to ~45 mph).
For timing, have maintained chc to likely PoPs across NW 1/2 of
the CWA from about 20Z and beyond, with minimal chances over
southeast VA and northeast NC through 00Z. Will need to monitor
situation closely given strong winds aloft and deep mixing as
even a few isolated late aftn tstms would be capable of
producing strong to severe wind gusts and large hail if they do
develop. The more widespread activity (though probably with a
lower chance for full blown severe wx) is expected after sunset
for most areas and likely PoPs/70% are in the forecast for all
zones. This will be with the added lift of the actual cold front
as it translates through the CWA from about 02Z northwest to
06Z southeast. Highs today to avg in the lower 80s except for
locally cooler conditions over the eastern shore and Outer Banks
(mainly in the 70s).
Pcpn will end/PoPs will decrease fm NW to SE after midnight
through 8 am Thu. Decreasing clouds also as WNW winds start to
usher drier air into the area behind the front. Lows tngt will
range fm the mid 40s northwest to the mid 50s southeast.
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
Strong CAA/much drier airmass continues to filter into the
region during Thu. Mostly sunny and breezy (at least in the
ern/NE counties), with highs ranging fm the mid 50s to lower
60s. Dry wx and chilly temps expected for Thu night in advance
of a secondary cold front. Lows in the mid 30s to near 40.
That secondary cold front swings acrs the region Fri
morning/aftn...bringing a chance of rain showers to extreme nrn
and NE counties. Highs on Fri will range fm the upper 40s to the
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Canadian high pressure then builds into the Mid Atlantic Region
Friday night into Saturday...shifting south of the VA/NC border
Saturday night and then off the Southeast Coast on Sunday. Low
pressure crossing the Hudson Bay should drag a weak cold front
across the nern half of the CWA again Sunday evening (similar to
Friday`s front) and could bring a stray shower across the Nrn
Neck to MD/VA Eastern Shore. Confidence not as high for shower
chances as long range models in the Day 6 timeframe do not line
up very well at all. Capped POPs at 10-14% in these areas for
now. The weak front exits well off the Delmarva Coast by Monday
morning, and the sfc high suppressed off the Southeast Coast
will rebound back into the area with mid-upper level ridging
moving in from the west as well. Next cold front to impact the
area is currently expected to cross the Midwest into the Ohio
Valley on Monday.
The long term period begins with temperatures at to slightly below
seasonal normals due to the cooler Canadian airmass Thursday night...
followed by Canadian high pressure Friday into Saturday. Plus the
region remains well-wedged within the cooler airmass through this
time. Lows Thursday night generally in the mid 30s inland (upper 30s
to lower 40s immediate coast). Highs Friday/Saturday in the lower 50s
(upper 40s far nwrn and nrn counties) despite decent west/downsloping
winds gusting to 25-30 mph. Colder lows Friday night as Canadian high
moves directly overhead. Expect readings in the mid 20s inland/around
30F (+/- a few degrees) at the beaches. As the sfc high shifts towards
the Southeast Coast Sunday, temperatures will slowly rebound above
normal with each passing day. Highs Sunday in the lower 60s (mid-upper
50s beaches, Nrn Neck, and MD/VA Eastern Shore). Lows Sunday night
in the lower 40s inland and mid-upper 40s closer to the coast. Highs
Monday around 70F (low-mid 60s beaches and MD/VA Eastern Shore). Lows
Monday night in the lower 50s with ample warm air advection ahead of
the aforementioned approaching cold front.
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
Initial warm frontal showers were moving off the coast early
this morning. But, increasing SSW winds and low level moisture
will result in lower MVFR or IFR cigs at the TAF sites
re-developing between 06Z-10Z and lasting until 15Z-16Z this
morning. Cigs will then improve back to VFR after 15Z-16Z today,
with SW winds 15-20 knots and gusts near 30 knots at times for
late this morning into this evening, in advance of the cold
front. That cold front will push acrs the area and off the coast
this evening into early Thu morning, with showers and tstms
ahead of and along the front. A few tstms could produce damaging
Outlook: High pressure and VFR conditions return for Thu and
into Thu night. A secondary, mainly dry, cold front crosses the
region on Fri. VFR conditions continue into the first half of
the weekend, as high pressure builds over the region.
Warm front continues to lift NE across the local waters early
this morning. Winds gradually becoming SSW attm...and will be
increasing through the morning hours. Strong WAA over the
colder waters today...the stability will limit mixing/higher
wind speeds except near the shoreline (through this afternoon).
SCA SW-W winds will become more prominent this evening/tonight.
A strong cold front crosses the waters late tonight. CAA in the
wake of the cold front will allow for higher wind speeds to
transfer down. A period of gales (at least gusts) expected w/
the initial cold air push Wed night...especially far northern
waters. Wind probs showing much higher potential (nearly 60%)
for gusts aoa 35 kt N of Parramore Island VA.
Moderate-strong SCA lingers until late morning/early afternoon
Thu then the pres gradient weakens and winds begin to wane.
Raising a gale for the nrn ocean waters this package
(07Z-17Z/02)...otherwise SCA will be in effect all waters
through 21Z/02. Another SCA will likely be needed Fri and Fri
night behind a secondary cold front.
Increasing SW winds today will bring the potential for low
water over parts of the marine area. The main threat is for
water levels of 1.0 to 1.5 feet below MLLW in the southern Ches
Bay at the time of low tide late this afternoon and again early
Thursday morning. Holding off on any advisory until after low
tide occurs early this morning.
Record high temperatures for today/March 1st:
RIC...80 in 1976
ORF...81 in 1918
SBY...80 in 1976
ECG...82 in 2012
Feb 2017 now ranks among the warmest and driest on record.
RIC and ORF ranks as the 2nd warmest, ECG is 3rd warmest, and
SBY is the 5th warmest.
Preliminary February Temperature ranks (average temps):
* RIC: (2nd warmest):
1) 49.9 (1890)
2) 49.0 (2017)
2) 48.5 (1976)
3) 48.1 (1884)
* ORF: (2nd warmest):
1) 52.4 (1890)
2) 51.5 (2017)
3) 50.5 (1909)
* SBY: (5th warmest):
1) 46.1 (1976)
2) 45.8 (1984)
3) 45.7 (1925)
4) 45.2 (1909)
5) 45.16 (2017)
* ECG: (3rd warmest):
1) 52.1 (1990)
2) 51.8 (1939)
3) 50.6 (2017)
Precipitation for Feb 2017:
* RIC: 0.71"/5th driest (0.48" in 1978 is driest)
* ORF: 0.66"/3rd driest (0.26" in 1918 is driest)
* SBY: 1.45"/not top 10 (0.24" in 2009 is driest)
* ECG: 0.92"/3rd driest (0.59" in 2009 is driest)
MARINE...Small Craft Advisory until 4 PM EST Thursday for ANZ630>638-
Small Craft Advisory until 2 AM EST Thursday for ANZ650-652.
Gale Warning from 2 AM to 1 PM EST Thursday for ANZ650-652.