Area Forecast Discussion
Issued by NWS Wakefield, VA-- Remove Highlighting --
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FXUS61 KAKQ 052351
Area Forecast Discussion
National Weather Service Wakefield VA
651 PM EST Mon Dec 5 2016
High pressure moves into New England tonight. A complex area of low
pressure crosses the region Tuesday, then moves offshore Tuesday
night. A strong cold front crosses the area Thursday. Cold high
pressure builds into the area late in the week.
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Latest MSAS has this mornings low well offshore with high pressure
over srn Ohio. Meanwhile, low pressure and associated fronts remain
over the deep south.
Models quickly move this high over PA this evening then into New
England late. This retreating high will allow moisture from the
south to quickly overspread the fa after midnight. Will first see
clouds increase this evening with overrunning pcpn breaking out
after 06Z first across the SW to near the Ches Bay by 12Z. Eastern
shore will likely stay dry. This timing is generally a model blend
given how the models generally underestimate just how fast pcpn can
break out. Pops will quickly ramp up late tonight (likely/cat)
across the SW...chc pops further east. Like yesterday, although
there may be a few sleet pellets mixed in at the start across the
NW, this will be insignificant and will not be mentioned in the
grids. Lows in the mid-upr 30s north to lwr 40s sern zones.
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
Tuesday appears to be a washout with widespread rainfall across the
fa. The initial low tracks NE to a position over the KY/Ohio valley
Tuesday afternoon while a secondary low develops along the stalled
coastal front. This coastal low progged to become the dominant low
as it tracks NE across eastern NC then the northern Outer Banks
Tuesday afternoon to a position east of VA Beach by 00Z Wed.
Abundant GOM / Atlantic moisture becomes entrained allowing for a
widespread mdt rainfall across the region. Given the progged
forcing, some of the rainfall could be heavy at times. Kept pcpn
type stratiformed for now but some convective elements are possible
after 18Z across the extreme SE. Any thunder progged to remain
offshore ivof Gulf stream. Added areas of fog to the grids as well.
Temps always a challenge given an insitu-wedge across the piedmont
and coastal front approaching from the SE. Little if any temp rise
expected across NWRN most zones where highs will be hard pressed to
reach 40. Temps stay in the 40s along and west of the I95 corridor,
50-55 coastal areas ranging to the upr50s-lwr 60s across the nrn
Outer Banks ivof the low.
Rainfall continues into Tuesday evening across the fa with the pcpn
quickly tapering off then ending SW-NE after midnight as the low and
best lift pull away from the region. Skies remain cldy with lows
from the mid 30s NW to upr 40s SE. Total QPF expected between 1 to
High pressure builds into the area from the west Wed and Wed night.
Dry with near seasonal conditions. Highs in the mid-upr 50s under pt
cldy skies. Lows in the mid 30s-lwr 40s.
Much advertised cold crosses the region Thursday. Initial band of
moisture progged to weaken as it crosses the mts given a downsloping
wind flow. However, enough moisture seen to carry low chc pops with
the fropa (30 pop north, 20 pop south). CAA not expected to kick in
until the moisture passes to the east so expect any pcpn to remain
in liquid form. Highs in the upr 40s-mid 50s but falling dp temps
in the afternoon.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Long term period starts off Thu night/Fri with dry weather behind an
offshore moving cold front. Main story in the extended will be cold
temps, with lows in the mid/upr 20s Thu night dropping to the
low/mid 20s Fri night and Sat night under continued dry weather with
sfc high pressure in the vicinity. High temps Fri and Sat avg in
the low 40s both days. Next chance of pcpn arrives Sun night/Mon
with an approaching cold front, but have capped pops for now at
20-30% with this several days out.
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
VFR conditions are expected at all terminals through the first half
of the night. Moisture from an approaching low pressure system will
begin to stream into the area after 00Z, leading to gradual lowering
of ceilings through the night. Winds should remain light through the
night out of the the NNE.
Rain is expected to overspread the region from south to northeast by
Tuesday morning. Guidance continues to show IFR conditions with
areas of fog, low ceilings, and the potential for some moderate
precip during the day on Tuesday. Have IFR conditions building in at
all TAF sites from west to east tomorrow late morning and into the
afternoon. Expecting the IFR to persist through the end of the
forecast period. Occasional periods of LIFR due to low ceilings and
visibility cannot also be ruled out at all TAF sites, generally
after 15Z Tuesday.
Outlook: IFR conditions continue into Tuesday night as the storm
slowly pulls away to the NE. Improving conditions to VFR behind the
system on Wednesday. A strong cold front will impact the area on
Thursday and bring a chance of scattered showers.
Latest sfc analysis shows high pressure in the vicinity with low
pressure developing near the GOM coast. The low advances
northeastward tonight, with another area of low pressure
developing over the eastern Carolinas Tue. Winds/waves/seas
increase ahead of the low, with SCA conditions expected over all
waters by Tue aftn. Latest guidance continues to increase winds
north and west of the sfc low as it strengthens offshore Tue
eveng/night, enough that there is 50% confidence for a few hours
of gale winds over the ocean, so have hoisted a gale watch there.
Highest likelihood will be over northern coastal wtrs. The low
pushes farther offshore Wed as weak high pressure builds into the
area with winds/waves/seas decreasing. Sca conditions may linger
into Wed with 5 ft seas continuing. A strong cold front then pushes
across the waters Thu, with strong SCA conditions to low-end gale
conditions possible Thu night through Fri night. SCA conditions
expected over the weekend.
MARINE...Small Craft Advisory from 1 PM Tuesday to 1 AM EST Wednesday
Small Craft Advisory from 10 AM Tuesday to 7 AM EST Wednesday
Gale Watch from Tuesday afternoon through Wednesday morning
Small Craft Advisory from 10 AM to 4 PM EST Tuesday for ANZ650-
Small Craft Advisory from 4 AM to 4 PM EST Tuesday for ANZ656-