Collington, North Carolina Weather Forecast Discussion

513
FXUS62 KMHX 251959
AFDMHX
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
359 PM EDT Thu Sep 25 2025
.SYNOPSIS...
High pressure will continue to extend over Eastern NC from the
northeast through today before a low pressure system moves in
from the west late week. As we get into next week we will be
monitoring the progress of Tropical Storm Humberto and Invest 94L.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 200 PM Thursday...
Key Messages
- Scattered strong thunderstorms with heavy rain and gusty
   winds possible this afternoon and evening
- Heat indices of 95-103 degrees this afternoon
Visible satellite imagery this afternoon shows a fairly well
defined lee-trough across the central Carolinas, with areas of
deepening cumulus ongoing. The latest RAP objective analysis
shows an uncapped airmass along and ahead of the trough, with
MLCAPE of 1000+ j/kg being analyzed. The uncapped airmass
extends east to near the coastal plain of ENC. East of there,
the airmass is still weakly to moderately capped.
Through the rest of the afternoon and into this evening, the
expectation is for scattered bands of convection to form along
the eastward-advancing surface trough as it shifts from central
into eastern NC. Some of the latest short-term guidance is
showing a slightly stronger signal for some convection to reach
the far western coastal plain of ENC in the 4-8pm timeframe.
Should this occur, steep low-level lapse rates and moderate
instability appears supportive of gusty downburst winds.
Additionally, analog guidance suggests some hail potential,
which seems plausible given ~25kt of deep layer shear aiding in
storm organization. Mid-level lapse rates will be weaker,
though, and this will tend to offset a greater hail risk.
PWATs are hovering around 1.50" based on the 12z MHX upper air
sounding, and guidance suggests these will be slower to increase
through tonight. This may be due to the strongest elevated
moisture transport being focused to our north for now. Still,
PWATs of 1.50- 1.75" and moderate instability should support
some moderate rainfall rates and possibly some minor urban/poor
drainage flooding. Thunderstorms should begin to wane well after
sunset as convergence weakens along the SFC trough.
Temperatures have warmed into the upper 80s to near 90 away
from the coast, with heat indices already reaching 95-100. I
bumped highs up for the rest of the afternoon given recent
trends, and this now gives the potential for 100-103 heat
indices for some inland locations.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
As of 200 PM Thursday...
Key Messages
- Increased risk of thunderstorms with heavy rain and gusty
   winds on Friday
A weak cold front is forecast to slowly shift south out of
Virginia on Friday, reaching ENC late Friday afternoon or Friday
night. Meanwhile, an upper level shortwave is forecast to lift
NE out of the AL/GA vicinity, reaching ENC Friday night. The
combination of improved lift, both aloft and at the SFC, should
support an increased coverage of showers and thunderstorms
compared to today. Once again, deep layer shear is forecast to
be around 25kt, which should support some storm organization.
The shear/instability combo appears supportive of gusty winds
and perhaps some hail as the primary risks. Additionally, deep
southerly flow should help boost PWATs up to 2", favoring heavy
rainfall and more intense rainfall rates. This appears
supportive of another chance of urban, small stream, and poor
drainage flooding. If convection were to train along the
seabreeze and/or the advancing cold front, an instance or two of
flash flooding would be possible.
The risk of showers and thunderstorms should last well past the
normal diurnal peak thanks to the approaching shortwave.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
As of 3 AM Thursday...
Key Messages:
- Unsettled pattern is expected across ENC through early next
  week
- Monitoring the evolution of Invest 94L and TC Humberto over
  the next several days for any indirect or direct impacts to
  ENC next week
There remains average to above average confidence in the large
scale upper level pattern through Sat/Sun with lower confidence
later in the period towards early next week. As a result, have
leaned on more of the ensemble and AI guidance later in the
forecast period in order to focus on the overall pattern, and
hash out specifics as we get closer to next week. Biggest
challenge in the long term will be the eventual track of Invest
94L and TS Humberto.
Saturday...Positively tilted upper level trough stretching from
the Interior Northeast to the Deep South will eventually take
on a more neutral to slightly negative tilt and cut off from
the upper level flow somewhere around the Tennessee River Valley
or Southeast. The exact track and strength of this upper low
will potentially have a part in the track of Invest 94L later in
the weekend and early next week but will get into that below.
Will note, still a fair amount of uncertainty with the exact
track and speed of this upper low. At the surface, cold front
will remain stalled near the coast through Sat. This will
likely promote periods of scattered to widespread showers and
thunderstorms across ENC. While not expecting severe weather,
could see training storms and therefore a low end (15% or less)
chance at excessive rainfall. With PWATs up around 1.5-2.0
inches rain could become heavy at times promoting a risk for
heavy/excessive rainfall and WPC has the area under a marginal
risk (level 1 of 5) for excessive rainfall Sat. Think Sat has
the better chance to see isolated flash flooding if we get a
fair amount of rain on Fri. High temps in the 80s Fri/Sat with
lows in the upper 60s to low 70s.
Sunday into midweek next week...Higher than avg uncertainty
expected in the forecast from Sun onwards given very complicated
upper level pattern around the Eastern Seaboard which leads
into the big question which is what will happen with Invest 94L
and TS Humberto early next week. Will go over the upper level
pattern and challenges and then potential solutions below.
Upper level cutoff low will meander around the Southeast and
Tennessee River Valley through early next week. Have followed
recent trends in the AI and ECWMF ensemble guidance which shows
the upper low pushing NE`wards early next week and exiting out
to sea by midweek as another trough dives SE`wards from the
Canadian Maritimes and provides an escape route for this upper
low out ahead of an upper level ridge to the west which will be
approaching at the end of the period. Key challenge here will be
the eventual track of the upper low as models notoriously have
a hard time handling this type of pattern and this low could
have an impact on the eventual track of Invest 94L. Otherwise
temps stay about or just below avg through the remainder of the
long term given expected ample cloud cover and widespread
precip.
At the surface, stalled front remains over the coast through
early next week before dissipating keeping things unsettled
through at least Tue with daily chances for showers and storms
across the region. Strong high pressure ridging begins to build
down across the region as well on Tue/Wed from the north and
west. At the same time TS Humberto and Invest 94L look to be
tracking NW to N on Sun and Mon with Invest 94L potentially
getting organized enough after it departs Hispaniola earlier in
the weekend to develop into a TD/TS around the Bahamas. TS
Humberto looks to continue off to the north and eventually the
NE closer to Bermuda as an upper trough leaves an escape route
for the system. The evolution of Invest 94L is where the
greatest uncertainty comes into play as multiple features will
play a role in the eventual track of the disturbance.
The first will be the speed in which Invest 94L develops. If
the system develops faster a quicker northward motion may occur
with greater impacts to the area, if slower development occurs
more interaction with TS Humberto is likely to occur limiting
impacts across ENC. The second will be the cutoff low in the
Southeast which if it moves far enough east could help to steer
94L closer to the coast. Finally an incoming ridge of high
pressure from the north could block the escape route of both
Humberto and 94L making the forecast even more complicated. With
this in mind and after taking a look at the 00Z ensemble
guidance it appears there will be three possible solutions for
early next week. The most likely as of right now is that after
94L tracks across Hispaniola, it will gradually develop on
Mon/Tue into a TD/TS and begin interacting with TS Humberto
resulting in a rare phenomena called the Fujiwara effect. With
94L likely being the weaker system at the time, TS Humberto will
flex its muscles on the disturbance creating an area of
enhanced wind shear over 94L keeping the system weak as well as
allowing 94L to attempt to circle around Humberto thus keeping
both systems out to sea and resulting in more indirect impacts
to ENC. The second solution which is currently less likely is
that 94L develops faster and the cut off low to its west is
closer to the coast allowing for less impact from Humberto and
thus allowing for a stronger system that moves more N/NW than NE
and brings more direct impacts to the area. Finally the least
likely solution is that Hispaniola disturbs the low level center
of 94L enough to result in no formation and TS Humberto
remaining well out to sea. Given the continued vast differences
in the forecast make sure you continue to stay weather aware
this week and be on the lookout for further updates.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
SHORT TERM /through 18z Friday/...
As of 200 PM Thursday...
Key Messages
- IFR/MVFR CIGs possible tonight (30-50% chance)
 - TSRA impacts possible through Friday (40-60% chance)
South to southwest low-level winds will help draw improved
moisture into the area through Friday, and will combine with a
surface trough approaching from the west, to support an
increasing chance of TSRA over the next 24 hours. Through this
evening, the greatest TSRA risk looks to be from KISO to KPGV.
The risk then shifts to much of ENC on Friday. With the
increased moisture advection comes the potential for low CIGs
later tonight into Friday morning. Guidance isn`t overly
enthusiastic about this potential, but we`ll be monitoring
trends for the potential development of IFR/MVFR stratus
tonight.
LONG TERM /Friday night through Tuesday/...
As of 3 AM Thursday...
Key Messages
- Unsettled pattern will bring unfavorable flying conditions
   to ENC into early next week.
A cold front is forecast to stall across the region this
weekend. This front will then move little through early next
week. As a result, will likely see an extended period with a
higher likelihood of sub-VFR conditions across ENC as scattered
to widespread showers and thunderstorms develop across the
area. Ceilings and vis will likely be reduced within any rain
and thunderstorm activity while outside of this activity periods
of VFR may be found between precip chances.
&&
.MARINE...
SHORT TERM /through Friday night/...
As of 200 PM Thursday...
Key Messages
- Increased risk of thunderstorm impacts Friday/Friday night
South to southwest winds of 10-15kt will build to 10-20kt
through this evening as the thermal gradient tightens across the
area. Occasional gusts of 20-25kt will be possible across the
Pamlico, Croatan, and Roanoke Sounds. A cold front will then
approach the waters from the north on Friday, with a weakening
gradient supporting winds laying down to 5-15kt. Seas of 2-3 ft
at 8-9s are expected through Friday night.
Through this evening, the thunderstorm risk should primarily be
focused offshore (10-20nm+). On Friday, the risk will begin to
increase for all waters as the above-mentioned cold front moves
into the area.
LONG TERM /Saturday through Tuesday/...
As of 3 AM Thursday...
Key Message
- Deteriorating marine conditions expected as early as Sun/Mon
Cold front is expected to stall near the coast this weekend.
This is forecast to bring a prolonged period of scattered
showers and thunderstorms to our area waters. A few storms could
be strong in nature resulting in locally enhanced winds and
seas. As we get into Sat seas remain at 2-3 ft while the winds
back to a SE to E`rly direction at 5-10 kts. As we get into Sun
and Mon, high pressure ridge begins to build in from the north
and with Invest 94L and TS Humberto off to the south and east
expect the gradient to tighten some allowing winds to gradually
increase to 10-15 kts on Sun and then 15-25 kts on Mon. Winds
will gradually become NE`rly by Mon as well. At the same time,
seas across our coastal waters will build, with 3-5 ft seas now
forecast by Sun and then 4-6 ft seas by Mon. At the very least
this will begin our period of unsettled marine conditions with
at the bare minimum, SCA conditions currently forecast.
&&
.TIDES/COASTAL FLOODING...
As of 300 PM Thursday...
Long period swell from distant Hurricane Humberto is forecast
to reach ENC beaches as early as Monday, then peak Tuesday and
Wednesday. Swell impacts may last much of the upcoming week, and
include dangerous rip currents, large breaking waves, and the
potential for ocean overwash and wave runup impacts. In the wake
of the tropical systems, a period of strong onshore winds
associated with a cold front may heighten impacts along the
coast, while also increasing the risk for soundside impacts
later in the work-week. Stay tuned through the week for updates
on the area of greatest impact, and the magnitude of those
impacts.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...None.
MARINE...None.
&&
$$
SYNOPSIS...MHX
NEAR TERM...RM
SHORT TERM...RM
LONG TERM...RCF
AVIATION...RM/OJC
MARINE...RM/OJC
TIDES/COASTAL FLOODING...MHX

NWS MHX Office Area Forecast Discussion