250
FXUS62 KRAH 061451
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
1051 AM EDT Sun Oct 6 2024

.SYNOPSIS...
High pressure centered near New England will extend into the eastern
Carolinas through this evening. A strong but moisture-starved cold
front will move east across the region on Monday. Canadian high
pressure will build into the region behind the front and persist
into next weekend.
&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1050 AM Sunday...

* Dense Fog Advisory was allowed to expire at 10am.
* Warmer than average today with increasing sunshine.

The latest surface analysis shows modest surface high pressure
centered over southwestern Quebec and eastern New England that
extends southwest into the mid-Atlantic and the Carolinas. The
airmass across central NC is rather dry with the PW observed in the
06/12Z KGSO sounding at 0.72 inches with is about 65% of average for
this time of year. Nearby soundings are similar with most of the
moisture noted below 800mb in a region of light north to
northeasterly flow. Further aloft, a light northwest flow is noted
at 500mb with a weakness/trough noted across SC/GA/AL with a strong
northern stream trough across the western Great Lakes.

Areas of dense fog this morning will continue to lift into a region
of stratus that will linger into the early afternoon across the
western Piedmont and VA border counties. Eventually, the stratus
will mix out this afternoon with mostly sunny conditions expected
areawide by early to mid afternoon. Morning low level thickness
values this morning are a little cooler than yesterday and will
support highs in the upper 70s across the VA border counties, Triad
area and the northwest Piedmont with lower 80s across the Sandhills
and southern Piedmont.

The northern stream trough will rapidly move east and become
negatively tilted as it moves from the eastern Great Lakes and into
New England. A pair of associated cold fronts will merge and move
across the crest of the southern Appalachians late tonight and move
into the Foothills of VA/NC toward daybreak Monday. Mainly clear
skies are expected tonight, most of the low level clouds associated
with the front will fade as they cross the NC mountains. A light
southwesterly wind is expected overnight ahead of the front. Lows
tonight will range in the upper 50s to lower 60s, or about 5 to 10
degrees above average. -Blaes

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
As of 355 AM Sunday...

Warmer yet, and mainly dry.

An elongated mean cyclone from Hudson Bay to srn QC will favor
broadly cyclonic flow over the nern quarter of the CONUS and mainly
dry, wnwly flow over cntl NC. At the surface, a couple of moisture-
starved cold fronts that will have merged and banked up west of the
Appalachians Mon morning will move sewd and across cntl NC Mon
midday through evening - probably a few hours slower than the models
depict at this time, given their fast bias for cP air masses
crossing the Appalachians. Tropospheric-deep wnwly to nwly flow will
downslope dry the already moisture-starved cold front(s) such that
only a 15-30 percent chance of showers will result over the
Sandhills and srn/cntl Coastal Plain, where frontal passage timing
will best coincide with peak heating and ~500 J/kg MLCAPE during the
afternoon-evening. Temperatures Mon should warm into the lwr-mid 80s
for most, with some upr 80s possible around MEB-FAY. Cooler and
drier post-frontal flow will favor cooler than recent days low
temperatures in the upr 40s to around 50 over the Piedmont to mid-
upr 50s elsewhere.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 220 AM Sunday...

Dry weather should prevail, with below normal highs and near normal
lows.

Aloft, the northern stream cyclone will gradually swing eastward
through southeast Canada and the Northeast US Tue-Thu, with central
NC under wly (Tue/Tue night), then nwly (Wed/Thu) flow as the broad
trough axis slowly shifts ewd through the area. Meanwhile to the
south, Milton should move through ctl FL Wed/Wed night, then
continue enewd toward Bermuda through Sat. As of the latest model
guidance, it appears the northern stream trough should keep Milton
south-southeast of the area. As Milton moves away from the East
Coast Fri/Sat, a s/w will swing through the lwr MS Valley and settle
over the Deep South. At the surface, the front will likely stall
over the Southeast US as Milton approaches and moves eastward
through FL, with high pressure ridging into central NC. Still expect
central NC to largely remain on the cool side of the boundary, with
nely flow prevailing through Sat. For now, most if not all of the
rain associated with Milton should stay out of central NC. There
could be a period of stronger winds/gusts on Thu, mainly across the
Sandhills and southern Coastal Plain, but that will depend on the
timing/track of the storm as it moves out over the Atlantic.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
As of 745 AM Sunday...

Widespread very low overcast and fog, and associated LIFR-VLIFR
conditions, will gradually lift and disperse to VFR through 16 or
17Z. Light surface winds and VFR conditions are otherwise expected
for the remainder of the 12Z TAF period.

Outlook: An otherwise moisture-starved cold front may support the
development of a band of showers from FAY to the coast late Mon
afternoon-evening. Canadian high pressure will follow and favor
mainly VFR conditions for the upcoming week. The exception to VFR
will be a chance of very shallow radiation fog at RWI Wed and Thu
morning.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Blaes
NEAR TERM...Blaes
SHORT TERM...MWS
LONG TERM...KCP
AVIATION...MWS