209
FXUS62 KILM 240959
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
559 AM EDT Tue Sep 24 2024

.SYNOPSIS...
High pressure to prevail through mid week with generally low
rain chances. More unsettled weather is expected later Thursday
thru Friday as a tropical cyclone moving northward out of the
Gulf of Mexico, passes west of the forecast area. Nevertheless,
look for possible impacts such as heavy rain, gusty winds and
coastal flooding. Cooler and drier high pressure should then
return later in the weekend into early next week.

&&

.UPDATE...
Coastal Flooding Warning has been issued for the Lower Cape
Fear River until 8 PM EDT and a Coastal Flood Advisory has been
issued for southeastern NC beaches until 4 PM EDT.

&&

.NEAR TERM /THROUGH TONIGHT/...
Similar day today with high pressure nosing southward into the
eastern Carolinas. Weak PVA along the northern periphery of the
ridge will produce isolated showers along and west of I-95 this
morning in a moisture-rich environment. Mesoscale ascent along a
shallow sea breeze could see a stray shower or storm this
afternoon, better chances as this boundary pushes inland.
Differential heating may also lead to the development of a stray
shower or storm inland, but morning clouds and showers could
impact this timing and probability. Minimal changes in low level
thicknesses today and have thus maintained a very similar high
temperature forecast to yesterday`s observations.

Warm tonight with lows in the upper 60s to around 70. Dry air
advection aloft may lead to a better chance of fog, particularly
in areas that see showers this afternoon.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
During this period, the FA will become sandwiched between upper
ridging off the SE States Coast, that transitions into a closed
upper high...and an upper low that drops to the Mid to Lower
Mississippi River Valley. Will be more under the influence of
the upper ridging and subsidence Wed. Thus low rain chances Wed,
mainly further inland ie. along and west of the I-95 corridor.
Thu, flow aloft becomes more southerly and moisture from the
Tropical Cyclone likely to reach atleast the southern portions
of the ILM CWA late in the day. End result, will have a range of
Pops Thu, hiest ILM SC CWA and lowest across ILM NC CWA. Highs,
warmer Wed over Thu. Lows, likely widespread 70s Wed Night.
Onshore flow will dominate during this period, increasing in
strength late Thu.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Thursday night thru Friday Night will be the ILM CWA`s potential
time dealing with direct and/or indirect effects from the
Tropical Cyclone as it passes well west of the FA, at this
juncture in the fcst. With the ILM CWA potentially in the
Eastern semi-circle, generally speaking, of this potential
tropical cyclone. Look for modest to strong onshore flow leading
to coastal flooding, heavy rainfall for sure and possibly
severe wx in the form of tornadoes. Will have a smaller range to
the diurnal temp curve Thu night thru Fri.

The upper low mentioned in the short term period is likely to
help steer it more northerly, or possibly with a westerly
component in that northerly direction. Come Sat, the bulk of the
moisture should be out of the forecast area followed by some
decent subsidence. Highs Sat may be underdone but for now will
not see-saw given the questionable track of the Tropical Cyclone
this far out in time.

For Sun into Mon, the lifting and movement of the upper low to
the Ohio and subtropical moisture feed aloft spreading overhead
from the SW, will atleast keep more cloudiness in the fcst and
a rain chance threat with low level flow from the NE-E.

To get the latest on the tropics, including preparedness info,
visit our tropical page at: weather.gov/ilm/tropical.

&&

.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
Low clouds developing across the area overnight, primarily
inland. Combination of MVFR/IFR with some fog possible at FLO
where clouds will be slow to develop. Onshore flow could lead to
the development of periodic MVFR along the coast. Showers along
the I-95 corridor will be possible after daybreak. Any
restrictions should be brief and limited to MVFR due to showers.
VFR today and a slight chance of late afternoon showers.

Extended Outlook... VFR conditions expected outside of predawn
fog and stratus. A tropical cyclone will likely pass near the
area Thursday night through Friday bringing a high chance for
restrictions and gusty winds.

&&

.MARINE...
Through Tonight...Southeasterly flow continues today and will
bolster a developing sea breeze. Gusts up to 15 knots near the
coast. Seas around 2 feet near the coast, increasing slightly
farther offshore to 2-3 feet. High pressure and ridging aloft
should keep showers and storms to a minimum.

Wednesday through Saturday Night...
Sfc ridging from the north will extend just east of the FA
during Wed resulting in E winds becoming ESE-SE at 10 or 10-15
kt Wed thru Wed night. An easterly swell at 10+ second periods
will dominate this period. For Thu, the sfc pg begins to
tighten from south to north resulting in continued SE winds but
increasing to possibly SCA thresholds late in the day Thu. Short
period wind driven waves will eventually dominate the seas
spectrum by late Thu. Thu night thru Fri, will observe the worst
conditions associated with the Tropical Cyclone as it tracks
west of the waters, well inland from the coast. Will be close to
Gale threshold winds Thu night into Fri, mainly from 35+ kt wind
gusts. Cannot stress again, that any deviation east of the
tropical cyclone will spell hier winds and resulting seas. At
this point, will fcst double digit seas Thu night into Fri. Fri
night thru Sat Night, look for a diminishing/subsiding trend to
winds and seas.

&&

.TIDES/COASTAL FLOODING...
Mostly minor coastal flooding remains a threat for the next
several days, especially in NC. However, future tropical
cyclone Helene could bring additional coastal flooding later
this week depending on its track/strength as it moves northward
from the Gulf of Mexico through the region.

The beaches are currently expected to reach minor flooding
levels (advisory criteria) during the afternoon high tide today
and Wednesday.

Moderate flooding is forecast along the Lower Cape Fear River
this afternoon and minor flooding is expected to occur during
each high tide over the next several days due to continued
upstream waters working their way down the river combining with
the high astronomical tides. Coastal flooding along the Lower
Cape Fear River will impact Downtown Wilmington and possibly
Brunswick County on the west side of the river, especially
during afternoon high tides.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...Coastal Flood Advisory from noon today to 4 PM EDT this
     afternoon for NCZ106-108-110.
     Coastal Flood Warning from 1 PM this afternoon to 8 PM EDT
     this evening for NCZ107-109.
SC...None.
MARINE...None.

&&

$$

SYNOPSIS...ILM
UPDATE...21
NEAR TERM...21
SHORT TERM...DCH
LONG TERM...DCH
AVIATION...21
MARINE...DCH/21
TIDES/COASTAL FLOODING...ILM