133
FXUS62 KRAH 161718
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
118 PM EDT Thu Oct 16 2025

.SYNOPSIS...
Canadian high pressure will build across and offshore the Middle
Atlantic states through Saturday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 100 PM Thursday...

* Lowest temperatures since mid-April expected tonight.

Aloft, central NC will remain under NW flow on the ern periphery of
a longwave ridge (progressing slowly ewd across the MS Valley), with
the deepening cyclone sliding swd off the New England coast, through
tonight. At the surface, Canadian high pressure will progress ewd
across the Great Lakes today, then sewd toward the mid-Atlantic
tonight, its ridge axis extending swd through the region. Highs
today still expected to top out in the mid 60s NE to low 70s SW.
With the subsidence aloft and high pressure building in at the
surface, expect dry weather, clear skies, and calm to very light
winds tonight, resulting in excellent radiational cooling
conditions. Low-level thicknesses should be in the 1335-1350 meter
range by 12Z Friday, which with the above in mind should result in
lows Fri morning ranging from mid/upper 30s to low/mid 40s.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
As of 115 PM Thursday...

As the cyclone moves ewd away from New England, the longwave ridge
will progress ewd to over the Eastern US, flattening some over the
region Fri night as an upper level s/w disturbance tracking ewd
across the TN Valley Fri aft/eve moves over the area. Primary impact
with this s/w will be some increased high clouds from W-E late Fri
through Fri night. At the surface, Canadian high pressure will
continue to move slowly ewd across the mid-Atlantic and Carolinas
Fri/Fri night. High temperatures should again range from mid 40s NE
to low 70s SW on Fri. Despite the high being over the area Fri
night, low level thicknesses are expected to increase to 1360-1370
meters by 12Z Sat, and with the increased cloud cover, lows should
be several degrees higher than the previous night, mainly in the mid
to upper 40s.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
As of 115 PM Thursday...

* Breezy conditions expected Sunday with frequent gusts of 20 to 30
  mph.

* A period of light rain remains possible late Sun afternoon into
  Sun night.

A longwave trough will sharpen over the MS Valley on Sun and is
expected to slide into the Mid-Atlantic Sun night into Mon night.
There are some discrepancies between the GFS/CMC and the ECMWF
global models and their respective ensembles on the character of the
trough and related secondary surface low placement. The ECMWF and
its ensemble members remain stubborn on a secondary low developing
over the Ohio Valley and shifting into the northern Mid-Atlantic
late Sun into Mon, resulting in overall tighter pressure gradient
and markedly better precip chances. A cold front is expected to
traverse the eastern seaboard as this low departs on Mon with high
pressure building into the region into midweek.

The forecast still suggest mostly light rain amounts (trace to
0.25") possible late Sun afternoon into early Mon morning as a band
of decaying convection and remnant MCVs are directed over the area.
Conditions will likely become breezy Sun afternoon with a tight
pressure gradient between the deep low over the Great Lakes and
broad high pressure just off the East Coast. Although we will likely
see partly to mostly cloudy skies, point soundings from 00z grand-
ensemble, 12z GFS and 12z NAM suggest gusts of 20-25 kts with
infrequent gusts as high as 30 kts possible; however, higher end
gusts will likely be confined to areas with limited cloud cover as
momentum transfer through the mixed layer is more efficient under
sunny skies.

There may be some fire weather concerns early to midweek behind the
cold front with downsloping winds, lower dew points, locally higher
wind gusts, and abnormally dry to moderate drought in the Piedmont
and Sandhills, but confidence in placement of surface features and
probabilities from 00z LREF are too low at this point to include in
the forecast.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
As of 100 PM Thursday...

24 hour TAF period: High confidence VFR conditions will prevail
through the TAF period. Winds will continue to be a bit breezy this
aft but should taper off after sunset to light/calm overnight.

Outlook: A cold front will move across cntl NC on Sunday, with gusty
winds, a band of low-end VFR to MVFR cigs, and a chance of showers
expected. Otherwise, VFR conditions will prevail through early next
week.

&&

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

&&

$$

SYNOPSIS...MWS
NEAR TERM...10
SHORT TERM...10
LONG TERM...AS
AVIATION...10