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219
FXUS62 KMHX 202328
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
728 PM EDT Mon May 20 2024

.SYNOPSIS...
High pressure builds in from the north keeping much of the area
dry through mid week before the next potential frontal system
moves through late week.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 130 PM Monday...

- Patchy, dense fog possible tonight (20-40% chance)

A mid/upper level ridge will shift east over the Carolinas
through tonight. Meanwhile, at the SFC, high pressure will nose
south out of the Northern Mid-Atlantic. This will keep a "cool"
northeasterly onshore flow going across Eastern NC through
tonight. Low-level moisture trapped beneath an inversion
(centered around 800mb) will continue to support periods of low
clouds through tonight. Of note, recent satellite imagery
reveals an area of low-level drying south of the Chesapeake Bay,
with an area of limited cloudcover stretching south into the
Albemarle Sound vicinity of Eastern NC. Short-term guidance is
insistent that this drying will be temporary, with low clouds
building back in through the night. Additionally, a moist
onshore flow plus light winds appears supportive of some fog
potential tonight. The general consensus of guidance is more
stratus than fog, and ensemble guidance only give a 20-40%
chance of dense fog across any part of the area. Given all of
the above, I will keep a patchy fog mention in the forecast, but
hold off on messaging dense fog for now. If clouds end up
clearing out, the fog threat would increase.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
As of 130 PM Monday...

- Near to below normal temps, and dry conditions, continue on
  Tuesday

Ridging aloft, and high pressure at the surface, will support
another day of dry weather across ENC on Tuesday. The main
forecast challenge Tuesday will be how quickly, or if, morning
clouds mix out. I suspect guidance is a bit too quick to erode
the morning clouds, although we`ll be losing the moist, onshore
flow as high pressure shifts overhead, so perhaps there`s some
credence to this. Assuming clouds mix out by the afternoon,
highs should reach close to normal inland, but still remain
below normal along the Outer Banks.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
As of 330 AM Monday...High pressure builds in from the north
for the first half of the workweek. A cold front will approach
from the west toward the latter half of the week.

Tuesday night through Thursday...High pressure builds across
the Mid- Atlantic and Southeast. Expect dry conditions through
Thursday, along with steadily warming conditions. By Wed and
Thu, temps rise through the 80s and back above climo. In fact,
some areas may flirt with 90 degree highs by Thu. Lows will be
in the 50s to start the pd, then rise into the 60s by mid week.

Friday through Sunday...Next potential weather maker in the
form of a shortwave trough and approaching cold front may arrive
by week`s end, bringing threat for thundershowers to the region
with a warm/humid airmass in place by then. Lots of
disagreement this far out, so pops only in the 30`s% at best.
Followed closer to climo, and kept thunder mainly in the
afternoon to early evening time periods, with very small to nil
shower chances overnight and morning periods.

&&

.AVIATION /23Z MONDAY THROUGH SATURDAY/...
-- Changed Discussion --
SHORT TERM /through 18z Tuesday/...
As of 7:15 PM Monday...Periods of MVFR and IFR ceilings are
expected through tomorrow morning with reduced visibility from
fog and low stratus development.Tonight, the cool and moist
northeasterly onshore flow will allow the low ceilings (MVFR to
low-end IFR) over the OBX to creep inland. By tomorrow morning,
lower ceilings will push back to the east and cloud cover will
diminsh across the coastal plain by the afternoon. Since the
afternoon update, confidence in fog has increased slightly
given the clearing of clouds over the majority of the coastal
plain. Obs will continue to be monitored and the TAFs will be
updated as needed.

LONG TERM /Tuesday night through Saturday/...
As of 4 AM Sat...Pred VFR conditions are expected early through
mid to late week.
-- End Changed Discussion --

&&

.MARINE...
SHORT TERM /through Tuesday/...
As of 130 PM Monday...

- Improving marine conditions over the next 24 hours

Breezy northeast winds of 10-20kt are ongoing across area
waters this afternoon thanks to a pinched gradient between low
pressure offshore and high pressure nosing south out of the
northern Mid- Atlantic. This is also supporting elevated seas of
4-6ft across the coastal waters. High pressure will shift south
into North Carolina tonight, then over Eastern NC on Tuesday.
This will allow winds and seas to lay down, supporting improving
marine conditions by Tuesday. In fact, winds should lay down to
<10kt for all waters on Tuesday, with seas laying down to 2-4
ft. The one fly in the ointment tonight and Tuesday morning will
be the potential for fog. Late this evening through about mid-
morning Tuesday, visibilities are expected to fall to 1-3NM,
especially across the northern waters. At this time, the
probability of <1NM visibility is 20-40%, and no marine dense
fog headlines are planned, but trends will be closely monitored.

LONG TERM /Tuesday night through Saturday/...
As of 4 AM Sun...High pressure will remain in control, favoring
good boating conditions through mid-week.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...Beach Hazards Statement until 8 PM EDT this evening for NCZ203-
     205.
MARINE...Small Craft Advisory until midnight EDT tonight for AMZ152-154.

&&

$$
SYNOPSIS...MHX
NEAR TERM...RM
SHORT TERM...RM
LONG TERM...TL
AVIATION...TL/OJC
MARINE...RM/TL