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fxus62 kilm 210756 

Area forecast discussion
National Weather Service Wilmington NC
256 am EST Tue Feb 21 2017

temperatures will remain unseasonably warm through much of the week.
High pressure extending down the East Coast today will shift
offshore Wednesday. A trough of low pressure will bring
increased cloudiness and some showers mid week. Near record
warmth will come Friday with an increasing chance of showers
ahead of an approaching cold front Friday night into Saturday.
Much cooler and drier high pressure will build in behind the
cold front Saturday night into early next week.


Near term /through tonight/...
as of 300 am Tuesday...expect dry weather to continue through
the near term. However, we will see increasing cloud cover,
initially primarily cirrus, as a complex mid-level trough
approaches eastern conus, with an upper low breaking off from
the base of the trough and spinning off into the northern Gulf
of Mexico. Satellite loops and model soundings both show this
scenario currently unfolding. Increasing cloud cover will knock
a few degrees off yesterdays highs, with Max readings this
afternoon of right around 70. Thickening cloud cover will also
moderate minimums overnight, with lows dropping only into the
lower and mid 50s.


Short term /Wednesday through Thursday night/...
as of 300 am Tuesday...retaining slight chance pops for much of
Wednesday and Thursday as an upper low and its developing
surface reflection swing out of the Gulf of Mexico and then
across Florida and the Bahamas. A generally amorphous pattern
with lack of any strong triggers and very dry mid-levels means
quantitative precipitation forecast will be kept on the minimal side. Temperatures will continue
to run unseasonably mild, with highs in the 70s and lows in the
50s for both days.


Long term /Friday through Monday/...
as of 300 am Tuesday...cutoff low exiting the Florida coast on
Friday will leave a surface low which rides up just off the southeast
coast through Sat morning. Should pull off a very warm day on
Friday with some clouds mixing with the sun and temps reaching
well into the 70s to near 80. A trough will extend up from this
low maintaining a more easterly flow at the sfc and as the low
approaches from the south in our off shore waters Fri night into
Sat, the winds will be more northeasterly. There will be a
general warm and moist return flow around Atlantic ridge
through the low levels, but this more easterly on shore flow at
the sfc will produce slightly cooler air flow on Sat, as well as
some clouds and shwrs possible. The sfc low will reach Hatteras
on Sat morning just about the same time a cold front will be
approaching from the west. The winds may veer around to the SW
soon enough before the front on Saturday to kick temps near 80
once again. The best upper level support will remain to our
north but expect some showers possible associated with this cold
front through Sat aftn.

Once the cold front moves off shore Saturday evening, high
pressure will build in with a deeper west-northwest flow of cooler and
drier air. Expect a dip in 850 temps from near 12c on Sat, down
below 0c Sat night through Sunday. Therefore our unseasonably
warm temps near 80 on Fri and into the mid 70s on Saturday will
not make it past 60 on Sunday. The high temp on Sunday will be
more similar to the previous night's low temps. Dewpoint temps
will drop a good 20 degrees leaving a very dry air mass for sun
into Mon. Clouds over the area Fri night into Saturday will
dissipate leaving plenty of sunshine for Sunday and Monday. With
high pressure moving closer overhead Sun night, should see
decent radiational cooling bringing temps down into the 30s


Aviation /06z Tuesday through Saturday/...
as of 06z...expect VFR through the valid taf period as high pressure
continues to build into the area. Mainly few/scattered cirrus expected
overnight into Tuesday as easterly winds remain around 5 kts. After
daybreak, northeast winds in the morning will return to easterly in
the afternoon, persisting around 5 to 10 kts. Cirrus will continue
to stream across the area as well, becoming broken/overcast towards the end
of the period.

Extended outlook... patchy fog possible late Tuesday night. Isolated
showers late Wednesday through Thursday. Showers possible Saturday
with a cold front. Otherwise expect VFR.


near term /through tonight/...
as of 300 am Tuesday...a weak high pressure system over the
western Atlantic will keep winds generally NE to east through today
and tonight with seas of right around 2 ft. Some 3 footers will
be present during the daylight hours, primarily over our NC
waters and out around 20 nm for our SC waters.

Short term /Wednesday through Thursday night/...
as of 300 am Tuesday...high pressure over the waters will keep
winds in the 10 kt range for Wednesday and Thursday. However,
longwave swell generated by a developing low over the Bahamas
will bring increasingly high combined sea heights, with seas
gradually building to 3 to 5 ft Thursday night.

Long term /Friday through Saturday/...
as of 300 am Tuesday...weak sfc low will move up the southeast
coast Fri into Sat. This will produce a more easterly flow and
possibly NE as the low reaches north toward Cape Fear by Sat
morning. The winds should remain less than 15 kts over most of
the waters but may reach slightly higher Fri aftn in the outer
waters. As this low tracks off toward Hatteras on Sat, a cold
front will approach from the west. Winds will back to the west-SW
briefly ahead of the front Sat aftn before shifting to the northwest
through Sat night and increasing up around 20 kts. The onshore
push through Fri will build seas up to 3 to 5 ft in the aftn and
up to 4 to 6 ft Fri night. Will most likely need some type of
precautionary or Small Craft Advisory headlines late Fri into early Sat.


Ilm watches/warnings/advisories...



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