Area Forecast Discussion
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FXUS62 KILM 250525
Area Forecast Discussion
National Weather Service Wilmington NC
1225 AM EST Sat Feb 25 2017
Warm air will prevail across the Carolinas through Saturday.
A cold front approaching from the west will move off the
Carolina coast Saturday Evening. Cooler and drier air under
high pressure will overspread the area Saturday night and
persist through Monday. Shower chances will increase by Tuesday
as a warm front moves across the area. Much warmer temperatures
will follow this warm front Wednesday before the next cold
front moves offshore.
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 945 PM Friday...Onshore winds via aftn and early evening
sea breeze, was able to push in 60+ degree sfc dewpoints. Have
incorporated these hier dewpoints and meshed them with the
overall hourly temps and dewpoint readings for the remainder of
this evening and overnight. Have kept skies mostly clear this
evening. However, various model mos guidance and model sounding
data, respectively, indicate that a threat for bkn to ovc low
level cloud deck below 1000 feet...in fact around 500 foot
ceilings likely during the pre-dawn Sat morning hours. Executing
the local fog procedure illustrates radiational type fog likely
to occur from east of the I-95 corridor to the immediate coast.
Have also indicated some patchy sea fog, although sfc dewpoints
are not progged to climb much hier from current readings. This
does not bode well for any widespread sea fog to develop and/or
occur considering current SSTs are in the upper 50s to low 60s
and sfc dewpoints are progged to be nearly the same or slightly
lower. A weak to modest low level SW jet progged to develop
just off the sfc, during the pre-dawn Sat hours. And it is
unable to mix down to the sfc overnight due to the sfc based
inversion having developed earlier. Have already seen sfc winds
decoupled earlier this evening with radiational cooling across
the FA leading to patchy to areas of fog development as well as
the eventual development of a low level stratus deck below 1k
feet. Have leaned toward the development of this low level
cloud deck more-so than the possibility of widespread
radiational (dense) fog. Tonights lows will continue well above
the normals...which is the mid 30s inland to the low 40s at the
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
As of 3 PM Friday...Another warm day Saturday with record highs
in jeopardy in some locations, most favorably inland. Records
in place for Saturday 2/25 include ILM-81 in 1930, FLO-78 in
1977, CRE-77 in 1949. Inland locations may see temperature drops
up 40 degrees or better from Saturday`s highs to Sunday`s lows
as a cold front sweeps through late Saturday. Moisture appears scant
with this system and only isolated showers painted in over SE NC.
Sunday sunny and cooler with highs in the afternoon reaching around
60 degrees. The coolest time of this forecast period is Monday
daybreak, widespread 30s inland and lower 40s near the coast, in a
light onshore breeze.
.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 300 PM Friday...Fast flow aloft will keep features moving
quickly next week, so while temps will remain above normal, the
weather is likely to be unsettled at times.
Cool high pressure Monday will push offshore as a warm front lifts
northward late in the day. This warm front will bring a chance for
showers Monday night into Tuesday, along with temps soaring back
well into the 70s Tuesday after just being slightly above climo on
Monday. Warm and unstable air behind the warm front will continue at
least a slight chc for showers through Wednesday as weak impulses
rotate overhead, but total coverage is expected to be isolated at
worst. This will change on Thursday however, as a strong cold front
digs across the Carolinas with a better chance for showers, followed
by much cooler temps for the end of the period. After several days
in the 70s, below climo temps are possible as we head into the first
wknd of March.
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
As of 06Z...Conditions currently VFR but moisture profiles support
fog tonight with good saturation below 500 ft. LIFR conditions are
likely after 08Z. Fog should dissipate by 13z with increasing SW
flow becoming more westerly aft 20z. Between 00Z and 04Z Sunday winds
will become NW at area terminals.
A potential fly in the ointment though will be the onset of more
southerly flow along the coast toward 12Z. As low level winds veer
late tonight, there is the potential for low stratus to move in over
the fog at the coastal terminals. This could do 2 things. First,
vsbys will likely be higher but cigs will remain IFR or LIFR.
Second, the improvement to VFR could be delayed at coastal terminals
during the morning. Attm confidence is low in this scenario.
Extended Outlook...VFR. VSBY and ceilings lowered to MVFR/IFR with
pcp Mon night into Tues and again with SHWRs on Wed.
NEAR TERM /THROUGH TONIGHT/...
As of 945 PM Friday...SCA remains in effect for all ILM Waters.
This due to significant seas breaching SCA thresholds. The
majority of the significant seas will be in the form of a 10 to
11 second period Southeast ground swell. The well offshore
cutoff and now barotropic low off the SE U.S. Coast will push
northeastward this weekend. The sfc pg will remain tightened
north of this cutoff low, producing a solid ENE to ESE 30+ kt
winds. The result is the production of a robust ESE-SE ground
swell at 10 TO 11 second periods that has been and will affect
the local waters thruout this weekend. They will likely peak
over the ILM SC Waters tonight and the ILM NC Waters thru
midday Saturday. The area waters overnight into the 1st part of
Saturday will see a lull in the windspeeds, dropping to around
10 kt with directions from the N to NE.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 3 PM Friday...Waning SE swell on Saturday, and midday the
advisories should be dropped for the NC waters, a little sooner
for the SC waters. However, as a cold front approaches, another
advisory or caution statement may be needed Saturday night, but
only briefly. Sunday will be a day of diminishing N-WNW winds and
improving marine conditions. No TSTMS this period but look for
a few marine showers late Saturday over the NC waters.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
As of 300 PM Friday...High pressure will move overhead and
offshore Monday with light E winds veering to the S/SW by
Tuesday morning and increasing to 10-15 kts on return flow.
Winds will then remain from the SW through the remainder of the
extended and increase slowly towards 20 kts during Wednesday as
the gradient pinches ahead of a cold front. Wave heights around
2 ft Monday will climb steadily as a SE swell and southerly wind
wave amplify through mid-week. Seas will build to 3-4 ft
Tuesday, and then up to 3-5 ft Wednesday during the period of
MARINE...Small Craft Advisory until 6 AM EST early this morning for
Small Craft Advisory until noon EST today for AMZ250-252.