FXUS61 KAKQ 220525
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
1225 AM EST Fri Feb 22 2019
A frontal boundary stalls over the Mid Atlantic and Southeast
states into Saturday, as high pressure builds eastward from the
Great Lakes into New England. The front will lift back north as
a warm front Saturday. A cold front will then cross the region
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 900 PM EST Thursday...
Latest MSAS has the frontal boundary across the sern states with
a sfc trof over the mts and high pres over the upr mid west. Skies
have partially cleared across the south this evening which has
allowed temps to fall to near the dew points resulting in ptchy
fog to dvlp. However, mid and high level clouds are quickly over
spreading the area from the west ahead of the moisture apprchg from
the wsw. Went ahead and put ptchy fog in across the south thru 06Z.
Although pcpn echoes increasing in coverage on the radar loop over
the wrn half of the state, sfc obs are still reporting CIGS aoa 10K
FT with no pcpn reaching the ground as of 02Z. Meanwhile, low IFR ST
along the coast is slowly creeping north this eve. Latest high res
data continues to show pcpn holding off until around 06Z the quickly
overspreading the local area during the pre dawn hrs. Thus, adjusted
PoPs a bit more with the highest PoPs after 09Z. Think the ptchy fog
arnd now scours out a bit once the clouds move in. Lows upr 30s north
to mid 40s south.
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
As of 355 PM EST Thursday...
More rain chances will continue Fri thru Sun morning. High
pressure will build eastward fm the lower Great Lakes to just
off the England coast Fri thru Sat aftn, creating another CAD
situation over the area. Waves of moisture/energy in the SW flow
aloft coupled with the return northward of the frontal boundary
as a warm front, will result in more chances for rain, esply
acrs the srn two thirds of the area Fri into early Sat aftn
(high chance to cat PoPs). Then, Sat aftn thru Sun morning, the
warm front will lift acrs the region followed by the approach of
a cold front. High chance to cat PoPs over most of the area
during this time period. The cold front will push off the coast
later Sun aftn/early Sun evening, with pcpn ending fm W to E
late Sun morning thru Sun aftn and a clearing sky. Westerly
winds behind the front will help high temps climb into the upper
60s to mid 70s acrs most of the region on Sun. Highs in the mid
to upper 40s Fri, and ranging fm the lower 40s to the lower 50s
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
As of 345 PM EST Thursday...
The flow aloft becomes more zonal across the CONUS early next week,
leading to less active wx across much of the country (including our
area). Drier (but still around average) Mon/Mon night as sfc high
pressure briefly settles into the region. Still dry/seasonable on
Tue as high pressure moves offshore. Highs on Mon will be in the mid-
upper 50s in most areas (except for low 50s on the Ern Shore). Lows
mainly in the upper 20s-low 30s Mon night w/ highs rising to around
50 on the Ern Shore/mid 50s-around 60 elsewhere on Tue. Lows Tue
night range from the low 30s N/NW to the around 40 SE.
Models diverge in their solutions for mid-late next week. Latest
12z/21 ECMWF is forecasting high pressure to settle into the Plains
(w/ sfc ridging extending to the nrn Mid-Atlantic region). The ECMWF
solution would lead to below average temps and mainly dry conditions
(perhaps a chc of light pcpn Wed night-Thu). The GFS is much warmer,
as it tracks a weak area of low pressure N of the region Wed-Wed
night (bringing light rain), w/ slightly cooler air settling into
the region on Thu. For now, went w/ a model blend from Wed-Thu and
kept slight chc PoPs in the forecast from Wed-Thu AM (for -RA).
Forecast highs are in the 50s on Wed, cooling to the mid-upper 40s
N/low-mid 50s S by Thu. Lows mainly in the 30s Wed/Thu night.
.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
As of 1225 AM EST Friday...
Another wave of moisture is streaming northeastward along a
stalled frontal boundary across the region. Patchy visibility
restrictions earlier tonight have improved as high and mid level
clouds stream into the area. CIGs are VFR/MVFR and will lower
progressively through the course of the day. CIGS are forecast
to remain in the MVFR range through 23.00Z before improving to
VFR. Slight visibility reductions to ~4SM are possible in areas
of precip Friday afternoon. Winds will generally be light and
variable overnight but will become northeasterly into the
morning hours. Generally below 10 knots for inland sites with
ECG and ORF having the greatest chance to see sustained winds
above 10 knots.
Outlook... MVFR/IFR conditions in rain, drizzle and fog
continue Fri night and Sat as a series of impulses move along
the stalled frontal bndry. The bndry moves north as a warm front
late Sat keeping unsettled wx conditions into Sun morning. A
cold front moves across the area Sun.
As of 215 PM EST Thursday...
Light winds will shift to the NNE through late aftn/early evening as
a weak frontal boundary drops south over the waters. Waves 1-2 ft;
seas 2-4 ft. Some increase in wind speed is expected early Friday
morning as sfc high pressure to the N sags south into the area. Have
speeds ~15 kt, and 15-20 kt for the southern coastal waters. With
NNE flow will have to watch to see if seas respond and try to build
to 5 ft. For now, not confident enough to issue SCA for this. High
pressure over the area Fri gradually retreats to the NE on Sat, as a
frontal boundary begins to lift back N as a warm front Sat night.
Winds will veer to the SE Sat night then to the SW and increase on
Sun as a stronger cold front approaches from the west. SCA
conditions appear likely Sun and Sun night, and potentially
lingering into Monday.
Noting Richmond Westham rising faster than anticipated this eve. Latest
update has the level of rise slowing then leveling off overnight but not
reaching flood stage until Fri eve. Held off on a warning attm given the
updated forecast. Other main stem rivers will see rises given the forecasted
rainfall over the next few days. Went ahead and added a blurb about this in