Scientific Forecaster Discussion
fxus61 kakq 111141
Area forecast discussion
National Weather Service Wakefield Virginia
641 am EST Wed Dec 11 2019
high pressure builds into the area today and tonight. Low pressure
develops along the Gulf Coast Friday, then tracks northeast along
the eastern Seaboard over the upcoming weekend.
Near term /until 6 PM this evening/...
as of 640 am EDT Wednesday...
The pcpn is quickly shifting east this morning and will end west
to east by noon. Had a burst of wet snow from ric on north along
i95 an hour ago which coated the ground in places. Otw, models
continue to show a rapid decrease in clouds right after the pcpn
ends with skies becoming sunny this aftrn. Cold air advection keeps it cold despite
the aftrn sunshine. Highs 40-45.
Short term /6 PM this evening through Friday night/...
as of 215 am EST Wednesday...
Clear/cold tonite as the center of the 1040 mb high tracks ENE ivof
the Mason-Dixon line. A secondary cold air advection surge will keep the winds up
over the waters and right along the coast, but expect decoupling
west of the Bay. Lows in the 20s to around 30 se.
The high slowly pushes off to the NE thurs. Cold despite ample
sunshine although some aftrn SC will apprch the coast due to the
persistant NE flow. Highs from the upr 30s NW to mid 40s se.
The high pushes off the New England coast thurs nite. Moisture from
the dvlpng systm to the SSW increases along a sfc trof ivof the mts
while addntl moisture is noted along a Carolina coastal trof. Dry
air in the lwr levels should keep it dry thru 12z Fri with the
exception of some rain creeping up from ern NC. Will increase the
cloud coverage in the grids but keep it dry as the models show
ridging east of the mts across the rgn. Lows in the upr 20s northwest to
lwr 40s southeast but will likely steady out or rise a bit towards sunrise
as the clouds come in.
The ridging slowly breaks down Fri with warm air advection moisture overspreading
the area from the SSW throughout the day. The deepest moisture will
come up from the SW during the aftrn. Thus, will have chc morning
pops becoming likely during the aftrn. Depending on how fast the
pcpn comes in, low lvl thicknesses suggest a possible brief period
of fz rain across nwrn most (climo favored) zones at the onset.
Highs from arnd 40 over the wrn most zones due to the insitu-wedge
ranging to near 60 across the nrn ob.
Widespread rain Fri nite (cat pops) as low pressure tracks NE along
the mid Atlantic Coastal Plain. Lows upr 30s northwest to lwr 50s southeast.
Long term /Saturday through Tuesday/...
as of 215 am EST Wednesday...
Low pressure tracks northeast Saturday and into interior New
England and Quebec, giving the area a dry northwest flow for
Sunday. Pcpn Sat morning, tapers off in the aftrn as trailing
cold front pushes east. Highs Sat range from near 50 northwest to lwr
60s southeast. Lows Sat nite upr 30s NW to mid 40s southeast. Dry sun with
highs in the low-mid 50s.
Dry conditions will continue into Monday as a cold area of high
pressure moves southeast across the Great Lakes Sunday night
into Monday morning. High pressure will be centered over the
area Monday with high temperatures on Monday in the mid 40s and
lows Monday night in the low 30s. Models are indicating that
another area of low pressure will develop in the northern Gulf
of Mexico and track into the mid-Atlantic Tuesday, bringing the
next chance of rain, and possibly wintry precip for the onset of
Aviation /12z Wednesday through Sunday/...
as of 630 am EST Wednesday...
Scattered-broken IFR ceilings in areas of rain (rain/snow mix at ric/sby) will
continue for the next 1-3 hrs. Pcpn quickly ends along with rapidly
improving ceilings to VFR as high pressure quickly builds east after
16z. Only scattered clouds along the coast by late in the day. Gusty north
winds (15-25 kts) this morning diminish to 10 kts or less after 18z.
VFR conditions cont thru thurs nite as high pressure tracks NNE
of the area. The next systm brings rain and degraded flight conditions
Friday through Saturday.
as of 320 am EST Wednesday...
The cold front has moved south and east of the waters and in its
wake, north to northwest winds have increased to around 15 to 25 knots with
gusts to 30 knots. These wind speeds will continue through the early
morning hours before diminishing later this morning and this
afternoon. Did not make any changes to the small craft advisories on
this update. A second surge of cold air advection is expected later this evening
and tonight (that does appear weaker than the current surge this
morning, but still in the 15 to 20 knot range) before high pressure
builds over the local waters Thursday. An additional round of scas
will likely be needed for at least the Chesapeake Bay, Currituck
Sound, and lower James for this next round. High pressure drifts off
to the NE later Thursday through Thursday night with low pressure
developing along the Gulf Coast Friday and eventually tracking north
to the mid-Atlantic Saturday.
Seas generally range from 4 to 6 feet this morning while waves in
the Bay range from 2 to 4 feet. Expect seas to remain elevated to at
or above 5 feet (especially out 20 nm) into potentially Thursday.
Seas decrease below Small Craft Advisory thresholds later Thursday for all locations
minus the southern coastal waters where these conditions may linger
through Friday. Seas build this weekend as the next system impacts
Marine...Small Craft Advisory until 1 PM EST this afternoon for
Small Craft Advisory until 10 am EST this morning for anz630-
Small Craft Advisory until 9 am EST Thursday for anz654.
Small Craft Advisory until 7 PM EST Thursday for anz656-658.
Small Craft Advisory until 6 am EST Thursday for anz650-652.