990
FXUS62 KILM 221914
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
314 PM EDT Wed May 22 2024

.SYNOPSIS...
High pressure will retreat offshore tonight and Thursday.
Shower and thunderstorm chances will grow as a series of upper
level disturbances move across the region late Thursday through
Saturday. Inland temperatures will rise into the 90s early next
week, then should cool behind a front Tuesday night.

&&

.NEAR TERM /THROUGH THURSDAY/...
Surface high pressure had been nosing in from the NE has retreated
and most of the area now seeing light S to SE winds. This will
remain the case for the entire near term meaning quiet weather
tonight with seasonable temperatures.  In the mid levels will will
transition from ridging to flatter flow, the latter always more
susceptible to housing shortwaves. The vorts depicted in guidance
are quite weak and for the most part stay to our north.  Will
continue to maintain POPs capped at 30 over nrn zones but could
definitely see how we get one last rain-free day Thursday.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
A positively tilted mid and upper ridge axis will move off the
Carolina coast Thursday evening, allowing colder air at 500 and
700 mb to flood in from the west across the Carolinas. The
strongly capped airmass we`ve enjoyed for the past couple of
days will be replaced by moderate convective instability, no mid
level cap, and precipitable water values up to 1.8 inches.

Although scattered showers or thunderstorms may dot the area
Thursday night into Friday morning, we`ll be watching for the
arrival of what could be a well-defined upper disturbance later
on Friday. This potential disturbance appears to be convectively
generated on the GFS/Canadian/ECMWF Thursday afternoon across
NE Texas and moves quickly eastward across the Mid South.
Assuming this actually occurs as expected, higher shower and
t-storm chances should develop here Friday afternoon into the
evening hours. SPC does not have a Day 3 risk area outlined,
however strengthened mid level flow and steep lapse rates could
generate a wind threat.

Saturday`s forecast gets a little murky given the potential for
subsidence and mesoscale capping behind any Friday night storms
lingering offshore, but I`m still going to keep scattered
mainly afternoon showers and t-storms in the forecast.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Our 500 mb heights should rise by 40 meters between Saturday
evening and Sunday evening as an upper level ridge across the
Gulf of Mexico expands northeastward. While it might seem like
an easy "win" to remove all convection from the forecast with
renewed capping aloft, there`s still the westerly upper level
flow to contend with which can easily bring fast-moving MCSs
across the Carolinas given rather subtle disturbances aloft. For
this reason I won`t stray too far from blended MOS PoPs through
the extended period.

As the ridging aloft builds Sunday and Monday it appears inland
high temperatures may soar to 91-94 degrees, near the warmest
of the year so far and similar to what we experienced back on
May 8th.

For Tuesday and Wednesday, all models want to carve out a trough
across the Great Lakes extending southward to the southern
Appalachians. There are indications 500 mb heights could fall
by 40-60 meters by Wednesday with decreases in temperatures
expected behind a Tuesday night cold front.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR for the most part, the only exception will be the chance for
some MVFR fog prior to daybreak. Continuity would argue for this but
since all guidance including probabilistic output has backed off
considerably fog has be cut back considerably from the forecast. ILM
in addition to radiation fog could see lower visibility roll off of
Smith Creek in the light SE flow.

Extended Outlook...Mostly VFR outside morning low clouds/fog through
Thu morning and periodic showers/storms starting Thursday night.

&&

.MARINE...
Through Thursday...The continued retreat of higher pressures will
continue to lead to minor veering of the winds from SE to S while
speeds remain capped at 10kt. With only a tiny swell component that
leaves mainly wind waves, capped at 2 ft through the period.

Thursday night through Monday...High pressure will retreat
farther offshore late this week as a weak cold front slowly
approaches from the northwest. Light southwest winds are
expected with seas only 2-3 feet. As the atmosphere becomes more
unstable getting out from beneath the warm ridging aloft,
isolated showers and thunderstorms could develop as early as
Thursday night with better chances developing Friday night. It
appears the front won`t make it down to the coastline, instead
stalling across interior North and South Carolina Saturday.
Thunderstorm outflow could temporarily shift winds across the
coastal waters northwesterly Saturday night, but winds should
come back around to the south and southwest again on Sunday.

Southwest winds should increase to 15-20 kt Monday as a strong
(for the season) area of low pressure moves across the Great
Lakes.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...Coastal Flood Advisory from 8 PM this evening to 1 AM EDT
     Thursday for NCZ107.
SC...None.
MARINE...None.

&&

$$

SYNOPSIS...TRA
NEAR TERM...MBB
SHORT TERM...TRA
LONG TERM...TRA
AVIATION...MBB
MARINE...TRA/MBB