Area Forecast Discussion
Issued by NWS Wilmington, NC-- Remove Highlighting --
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FXUS62 KILM 261553
Area Forecast Discussion
National Weather Service Wilmington NC
1153 AM EDT Mon Sep 26 2016
A stationary front will remain in that area this afternoon before
pushing northward on Tuesday ahead of a cold front. This cold
front will slowly cross the region on Wednesday before moving off
the coast on Thursday. Cooler and drier weather is expected by
.NEAR TERM /THROUGH TONIGHT/...
As of 1150 AM Monday...A stationary front will slowly shift
northward as a warm from throughout the day. The model soundings
and upper air sounding from mhx are showing moisture is generally
contained below 700 millibars this morning. This will change with
the frontal boundary moving to the north and deeper moisture is
expected to return later today into Tuesday. The moisture will
increase south of MYR and west of FLO and LBT.
This evening and overnight cloud cover will increase with a chance
of showers overnight. For temperatures, highs today will reach
the middle 80s and lows will fall to around 70.
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 400 AM Monday...Amazingly, the models have the general idea
of a closed low dropping south from the Great Lakes and becoming
a cutoff low by the end of this period as the westerlies
bypass this system by the end of this period. Like spokes on a
bicycle, weak mid-level vorts or S/w trofs, rotating counter-
clockwise around the upper low, will occasionally affect the FA
this period. More-so when this upper low drops to the central
Appalachians. These s/w`s will be able to interact with dynamics
from the slow moving sfc cold front slithering across the FA.
POPs will be advertised each day, likely hiest during Tue thru
early Wed, due to the passage of the sfc low along the inverted
sfc trof just off the coast. With the cold pool aloft partially
reaching the area during the latter half of this period,
increasing the lapse rates and instability due to the days
insolation, the chance for thunderstorms will exist thruout this
period. For temps, leaned toward the European MOS Guidance over
the GFS Mos due to its recent and slightly better performance.
.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 300 AM Monday...Big differences in the extended continue to
cause lowered confidence for late this week. While the guidance all
shows a deep trough closing off across the OH VLY, the evolution
thereafter becomes quite muddled. The ECM continues to be a
strong/slow/west outlier with this feature as it digs into the lower
Appalachians and then actually retrogrades to the NW through
Saturday before finally ejecting late in the wknd. The GFS/CMC are
more in line with a sharp digging through Thursday and then lifting
off to the NE through New England Friday and into the wknd. Although
the ECM has been consistent the last few days, the GFS solution is
still preferred as a retrograde west of the upper low into a +3 SD
ridge seems unlikely. WPC cannot rule out any solution at this time
however, so a blended forecast is preferred with highest weight on
This upper low will determine the passage of a surface cold front
which continues to slow in forecast guidance. Favoring the GFS,
FROPA is now expected early Thursday, with cool and dry weather
expected Fri-Sun. In fact, temps Fri-Sun may fall slightly below
climo for both highs and lows as the first fall-like airmass of the
season advects into the Carolinas beneath Canadian high pressure.
Will note that if the ECM solution verifies, the front won`t cross
until Saturday, leaving much more unsettled weather through the
week, along with continued above normal temperatures.
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
As of 12Z...A washed out front will remain nearly stationary and
dissipate today. Predominately easterly flow, a bit more
northeasterly early on. There will be quite a bit of a high
stratocu deck this morning, more scattered by this afternoon.
Tonight some fog entering the picture well after midnight, mainly
EXTENDED OUTLOOK...Chance for SHRA/TSRA each day through
Wednesday, with morning fog/stratus also possible. VFR Thursday
NEAR TERM /THROUGH TONIGHT/...
As of 1152 AM Monday...A stationary front over the waters will
slowly move north this afternoon with the winds mainly from the
east-northeast to east between 10 to 15 knots. seas will range
between 2 and 4 feet with a 1 to 2 foot east- southeast swell of
an underlying 1 to 2 foot east-southeast ground swell around 9
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 400 AM Monday...Will see a veering trend to the winds from
easterly at the start of this period, to south southwest by the
end of this period. Weak sfc low to move along the inverted sfc
trof Tue. A sfc cold front to drop SE at a snail`s pace this
period, moving from the Appalachians early Tue, to the local
waters by early Thu. Wind speeds may become temporarily northerly
up to 15 kt after the low passes by early wed, otherwise looking
at around 10 kt for speeds with the sfc pg relaxing up until the
sfc cold front reaches the coast. Significant seas will run 2 to 3
ft, possibly and briefly up to 4 ft at the start of this period
due to the passage of the sfc low. Wind driven waves to dominate
thru early Wed with periods running 4 to 6 seconds. The ESE, 1 to
2 foot ground swell at 9 to 10 seconds.
LONG TERM/THURSDAY THROUGH FRIDAY/...
As of 300 AM Monday...Still some uncertainty in the extended with
respect to a frontal passage, but attm expect FROPA to occur
Thursday with W/SW winds around 10 kts becoming NW late. High
pressure will build in behind this front creating a very weak
pressure gradient, so winds across the waters on Friday will
feature highly variable direction with speeds of 5-10 kts. Seas of
2-3 ft Thursday will fall to around 2 ft on Friday thanks to the
weaker winds, and a continuing 2ft/9-10 sec SE swell.