Area Forecast Discussion
Issued by NWS Wakefield, VA
FXUS61 KAKQ 291727
Area Forecast Discussion
National Weather Service Wakefield VA
127 PM EDT Sat Apr 29 2017
Bermuda high pressure prevails off the Southeast Coast through the
weekend. A backdoor cold front will drop south across the northern
Delmarva peninsula tonight then lift back north as a warm front
Sunday. The next cold front pushes across the region Monday night.
.NEAR TERM /THROUGH TONIGHT/...
A strong mid/upper level "Bermuda" ridge is located off the
Southeast coast, with an active stream of convection on the nrn
periphery of the ridge from the Central Plains through the Ohio
Valley. At the surface, high pressure is co-located with the
ridge aloft offshore, with a stationary front from the Midwest
to the Northeast. Morning stratus has been stubborn to erode
this morning, with temperatures in the mid 70s to around 80F.
The morning stratus should erode by midday, with sct cu and ci
aloft by aftn resulting in partly sunny conditions. Today should
be the hottest day with 850mb temperatures around 17-18C, which
will support summer like highs in the low 90s W of the Bay,
85-90F for the Ern Shore, and low 80s at the beaches. A SW wind
of 10-15mph will gust to around 20 mph. Record highs will be
approached, see the climate section below for more details.
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
Bermuda high remains in control. However, a s/w low will track along
the frontal boundary to the north. Once this low moves east, the
boundary is progged to sag south. However, the models differ in
position of the boundary which poses a challenge for pops tonight.
NAM farther north and keeps the fa dry while the GFS has the
boundary as far south as AKQ northern zones. Given the differences,
elected to keep the current grids which shows a 30 pop across the
lwr Md eastern shore through 06Z with a buffer area of slght chc
pops. Warm and humid with lows from the mid 60s to lwr 70s.
The front then lifts back north a bit keeping the fa in the summer
like airmass Sunday. H85 temps somewhat cooler than Saturday (14-
16C). Mstly sunny with highs in the mid-upr 80s west of the bay, low-
mid 80s easterrn shore except 70 at the beaches.
Dry Sunday night as the models keep pcpn west of the fa thru 12Z
Mon. Pt to mstly cldy and warm. Lows in the 60s.
Moisture progged a bit slower east ahead of the apprchg cold front
Mon. Backed off on pops thru abt noon Monday. Pops quickly ramp up
Monday afternoon as a decent feed of moisture in noted, especially
west of I95 (chc to likely pops after 18Z). Ridge holds tight along
the coast so think most areas stay dry thru 21Z. PW`s arnd 1.5 inches
so kept mdt rainfall rates in the grids. Highs in the low-mid 80s
except 75-80 along the coast.
Cold front crosses the fa Monday night and offshore by 12Z Tue. A
decent slug of moisture progged ahead of it. Adjusted the grids for
better timing of the pcpn with likely pops across the west during
the evening then chc pops after midnite. Chc pops during the evening
along the se coast with likely pops after midnight. Turning cooler
with lows from the upr 50s NW to mid 60s SE.
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
Weak high pressure will provide dry wx for Tue morning thru Wed,
as it slides fm the Gulf coast states to off the SE coast. Lows
Mon night in the upper 50s to mid 60s. Highs on Tue in the mid
70s to lower 80s. Lows Tue night ranging thru the 50s into the
lower 60s. Highs on Wed ranging thru the 70s to near 80. Low
pressure will approach fm the WSW late Wed night thru Thu, then
lifts just WNW of the area during Fri while pushing a cold front
into the region. Pops will increase to high chc on Thu, then high
chc to likely Pops for Thu night and Fri. Highs on Thu will range
fm the upper 60s to upper 70s. Lows Thu night will range fm the
lower 50s to lower 60s. Highs on Fri will range fm the mid 60s to
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
A stationary front will stay north of the area through the
forecast period. This should allow for VFR conditions through
tonight. One exception to this may be at SBY this evening as a
weak disturbance moves along the front which may help bring
scattered showers and storms to the eastern shore, allowing
conditions to breiefly drop to sub VFR conditions. In addition,
the guidance suggests some marine air will move into the eastern
shore overnight into Sunday morning as the front briefly moves
south of SBY, potentially allowing for MVFR conditions.
Outlook...Mainly dry weather expected through the remainder of
the weekend, although some convection is possible across Delaware
tonight along a backdoor cold front. Next frontal boundary late
Monday into Tuesday with possibility of showers and thunderstorms.
No headlines necessary with this forecast package. Broad Bermuda
high pres allows for 10-15 kt S/SW flow today, with 1-2 ft waves
over the Bay and 2-4 ft seas over coastal wtrs. A backdoor front may
drop into northern areas tonight, before pushing back north as a
warm front Sun. S/SW winds again 10-15 kt Sun with the high
offshore. Next cold front approaches the area Mon, and with a tight
pres gradient ahead of the front, SCA conditions of 15-25 kt
sustained winds gusting to 30 kt are likely starting around midday
Mon, lasting into Mon night until the cold front crosses the wtrs.
Winds decrease into Tue as CAA is weak behind the frnt.
Keeping flood advisory in Mecklenburg county going today, with
VDOT continuing to report numerous roads closed in the Kerr Dam
area, creating ongoing navigation concerns.
It still appears likely that Richmond and Norfolk will each end
the month with the warmest April on record. Very warm temperatures
expected today and an unseasonably warm April to date should combine
to push the April 2017 average temperature above that which occurred
in 1994. As noted below, both of the previous records on the books
were established in 1994. This month`s temperatures look to end up
around one degree above those values.
Average temperatures / Record Average Temperature
Avg temp Record
Location to date Avg temp Year
-------- -------- ------ ----
Richmond 63.1 63.2 1994
Norfolk 65.3 64.7 1994
Record high temps for today 4/29:
RIC...93 in 1974
ORF...92 IN 1974
SBY...89 IN 1974
ECG...90 IN 1974
Record high min temps for today 4/29:
RIC...67 in 1956
ORF...66 in 1981
SBY...65 in 1974
ECG...67 in 1981