Scientific Forecaster Discussion
fxus61 kakq 202104
Area forecast discussion
National Weather Service Wakefield Virginia
404 PM EST Tue Feb 20 2018
high pressure becomes anchored off the southeast coast through
Thursday. A backdoor cold front moves south across the area
Thursday, then meanders across the region through the end of
Near term /until 6 am Wednesday morning/...
warm front now north of the area with the 500 mb Bermuda ridge becoming
the dominate wx feature. Model guid suggests another night where
stratus and ptchy fog develop then lower as the night progresses.
NAM even has some drizzle after midnite. Once again, to early for
any headlines but will indicate fog/late nite drizzle in the grids.
Exception will be over the water where vsbys will quickly go below
one nm this evening, thus a marine dense fog advsry has been issued.
Given crnt dew point temps, expect some record high mins to fall.
See clisection below. Lows 55-60.
Short term /6 am Wednesday morning through Friday night/...
morning low clouds/fog burn off with a pt to mstly sunny and
warm aftrn. Record highs at ric/sby will likely fall, it will
come close at ecg/orf. Highs 75-80 except holding the 60s at the
The backdoor cold front approaches from the north Wed night with
its location across the northern akq zones by 12z Thu. Moisture
incrs along and ahead of this boundary with low chc pops for shwrs
across the nrn half of the fa by morning. Still warm ahead of it
with another night where fog will be possible, especially over
the water. Lows 55-60 except 50-55 ern shore areas.
Forecast then becomes a bit more complicated as the models differ on
just how far south the bndry gets. GFS stalls it across the fa while
the NAM/European model (ecmwf) push it south into NC. Moisture remains confined mainly
to areas along and north of the VA border so will keep chc pops to
low end likely across the far north. Tmps tricky as they will highly
depend on the fronts location. Could even see stdy or slowly falling
readings as the front drops south. Highs 50-55 ern shore to low-mid
70s across nern NC.
Cooler thurs nite with chc shwrs as a moist onshore flow develops.
Lows in the 40s. Will keep chc shwrs going Fri due to the moist
onshore flow. Highs in the lwr 50s north to lwr 60s south.
Long term /Saturday through Tuesday/...
a boundary is expected to set up north of the area on Saturday
leading to southwest flow and very warm temperatures with highs
climbing into the low to mid 70s for a good portion of the area
(cooler across the eastern shore). We should stay dry for a good
portion of the day Saturday with the highest rain chances closer to
the boundary across the north and west. Chances for showers will
increase from the northwest Saturday night into Sunday as a cold
front begins to approach the region. Mild temperatures are expected
on Saturday night with lows generally ranging from the mid to upper
The cold front crosses region during the day on Sunday bringing a
chance for showers (and potentially some isolated thunder) to the
area. Another mild day out ahead of the front on Sunday with highs
in the 70s for much of the area. Showers may try to linger Sunday
night into Monday, especially across the east. Lows Sunday night
will range from the mid 40s northwest to the lower 50s southeast and highs Monday
will range from the upper 50s to mid 60s. High pressure builds
across the region Monday night into Tuesday.
Aviation /21z Tuesday through Sunday/...
IFR/MVFR stratus hanging Tuff at orf/phf/ecg/sby Erly this
aftrn while ric has only sct SC. The fog has lifted. Still
expect a slow scouring out process in the clouds this aftrn so
kept ceilings rather low to start off the forecast period. Appears a
repeat performance is likely again tonight as the models show a
few hr period of MVFR/VFR conditions this evening before the
stratus and fog develop again. Expect the stratus to lower
bringing down the vsbys into the IFR range. Morning clouds/fog
burn off Wed with VFR conditions expected by the aftrn.
Outlook... a back door cold front approaches from the northwest Wed
night then drops south across the area on Thu. Expect a return
to IFR/MVFR conditions in rain/fog Thu/Fri behind this feature.
no headlines in the short term tonight thru Thu. Late this aftn,
sfc high pressure was cntrd well off the mid Atlc coast,
providing southerly winds 5-15 kt over the waters. Areas of fog
and stratus were still lingering over portions of the waters
also, and likely will re-develop over most of the waters later
this evening into Wed morning. Thus, a dense fog advisory has
been issued for the entire marine area until 10 am Wed.
Otherwise, expect south-southwest winds 5-15 kt tonight into early Thu
morning, then winds shift to the north-northeast 5-15 kt Thu into Fri, as a
backdoor front drops thru the region. The front then lifts back
north as a warm front later Fri, and will move north of the
region Fri night. Waves/seas will increase Thu into Fri.
another round of record highs will possibly be challenged Tue
2/20 and Wed 2/21:
* record highs:
* date: Tue 2/20 Wed 2/21
Ric: 77 (1930) 75 (1930)
orf: 77 (1991) 79 (2014)
sby: 75 (1930) 75 (1943)
ecg: 78 (1991) 77 (2014)
* record high mins for 2/21.
Ric: 54 (1953)
orf: 58 (1953)
sby: 51 (1953)
ecg: 61 (1939)
Marine...dense fog advisory until 10 am EST Wednesday for anz630>638-