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000
FXUS62 KILM 181121
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
721 AM EDT Tue Sep 18 2018

.SYNOPSIS...
A front will cross the Carolinas today, exiting off the coast
by Wednesday morning. This will usher much drier air into the
region, with no significant precipitation expected this week as
high pressure builds in from the north. Lingering effects of
Florence will be felt for days to come as dangerous river
flooding continues.

&&

.NEAR TERM /THROUGH TONIGHT/...
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As of 300 AM Tuesday...Coastal Flood Advisory for downtown
flooding has expired at 7am and area wide Flood Warning has
been extended until 7pm on Wednesday. Mid-level s/w energy and a
sfc frontal boundary will combine to produce showers and
isolated thunderstorms early this morning. Once insolation
commences this morning, the atmosphere will further destabilize
resulting in additional thunderstorm activity. A few of the
stronger storms could produce 30 to 45 mph wind gusts later this
morning and aftn. In addition, rainfall amounts will generally
run one- quarter to 1 inch with isolated hier amounts possible.
The locations not within our Areal Flood Warning that runs thru
1015 AM today include...Williamsburg County and the southern
half of Georgetown County. However, enough pcpn has fallen to
warrant atleast a Flood Advisory for Minor Flooding in the
mentioned locations thru 645 AM this morning. Overall, POPs will
run 30 to 50 percent today early this morning thru this
afternoon then drop off from NW to SE as the front pushes off
the Carolina coasts this evening and overnight. Models are
similar in taking the drier air and infiltrating it across the
local area this evening and pre-dawn Wed hours. PWS in the 1.6
to 1.9 inch range or progged to drop to around or below 1 inch
come Wed daybreak. A WELCOME CHANGE to say the least. Temps
followed the consensus amongst the models with a 80s to around
90 for highs today and 70 to 75 for tonights lows with possible
upper 60s along and west of the I-95 corridor where the drier
air having worked in.
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&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 300 AM Tuesday...The start to a dry period across the
Carolinas, with a change in air mass, as high pressure builds
in behind an exiting front Wed into Thurs. At the same time the
mid to upper ridge will migrate across the Southeast taking up
residence nearly overhead by Thurs night. A deep northerly flow
will advect dry air into the area with pcp water values down
less than 1.5 inches to start the day on Wed. These values will
decrease further to less than 1.25 inches through the period as
sfc high pressure continues to extend down from the north as it
migrates eastward toward the coast. Overall expect dry and warm
weather during the day with temps in the mid 80s both days, but
a couple of degrees less on Thurs. Overnight lows will feel a
bit cooler as lower dewpoint air will allow for greater diurnal
swings with temps dropping below 70 many places inland Wed night
and down into the mid 60s Thurs night.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 300 PM Monday...Mid-level high pressure will dominate the
upper levels through Sunday. The 500 mb ridge Will shift south of the
area and a weak front will be along the Virginia-North Carolina
border on Monday. The precipitable waters are expected to be at or
below 1.25" through Sunday. What this means is the chances for
precipitation will be low with a slight increase on Monday afternoon.

High temperature are expected to be in the middle to upper 80s
through the period. With lows in the upper 60s inland to the lower
70s at the coast.

&&

.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
As of 06Z...Scattered convection will occur early this morning,
basically along and south of a line that runs from ILM to FLO.
Mid-level support will aid in keeping this convection ongoing
overnight into daylight Tue. Low level clouds will dominate the
early morning terminal sites with only patchy fog possible due
to winds staying active from the south at 5 to 9 kt.

A cold front dropping southeastward during Tue combined with
upper level dynamics that may be partly of Florence remnants,
will keep the threat for showers and tstorms thruout the day on
Tue. Could see residual clouds and early evening shra before the
cold front pushes south of the area by the end of this period.
After FROPA, winds will become NW-N at 4 kt or less with the
threat for patchy ground fog at the end of the 24 hr TAF
Issuance period.

Extended Outlook...Predominately VFR throughout the extended
period due to ridging aloft and high pressure at the sfc keeping
a lid on convection development.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
As of 300 AM Tuesday...Ahead of the sfc frontal boundary, the
sfc pg will remain tightened with the sfc pressure pattern
yielding S-SW winds 10 to 20 kt to start, veering to the WSW-WNW
as the front pushes across the waters this aftn and early
evening. And finally, further veering to the NW-NE after the CFP
later tonight and pre- dawn Wed hours. Speeds at the end of the
period will run 10 to 15 kt. Models may be under-estimating the
dry surge after the CFP but for now will keep it at 15 kt
speeds. Significant seas will be initialized in the 3 to 4 foot
range with occasional 5 footers. As winds veer and become
partially to mostly offshore later tonight, the seas will see a
decline by atleast a foot come daybreak Wed. Dominant periods
will run 6 to 8 seconds with an underlying small SE groundswell
at 11 to 13 second periods.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 300 PM Monday...A sfc front will be crossing the waters
Wed morning. NW winds behind the front will veer to N on Wed
and will continue to shift around to the NE by Thurs and more
easterly by Thurs night as high pressure builds down into the
waters from the north and then migrates eastward. Winds 10 kts
or less Wed morning will increase to 10 to 15 kts Wed night into
Thurs. Seas on a downward trend to 2 to 3 ft through Wed will
jump up a bit Wed night into Thurs, to 3 to 4 ft.

LONG TERM /FRIDAY THROUGH SATURDAY/...
As of 300 PM Monday...High pressure will be over the coastal
waters through the period. Winds will shift to the east and
weaken to 5 to 10 knots on Fri into Sat. Seas will range
generally in the 2 to 3 foot range.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
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SC...Beach Hazards Statement through this evening for SCZ054-056.
NC...Beach Hazards Statement through this evening for NCZ106-108.
MARINE...None.
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&&

$$

NEAR TERM...DCH/RGZ
SHORT TERM...RGZ
LONG TERM...RH
AVIATION...DCH