475
FXUS62 KRAH 161052
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
652 AM 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 315 AM Thursday...

A longwave ridge over the MS Valley this morning will progress ewd
and extend from the cntl Gulf basin to the Great Lakes by 12Z Fri.
Downstream of the ridge, nwly to nnwly flow aloft and deep
subsidence will prevail across cntl NC.

At the surface, the center of Canadian high pressure will progress
from the Great Lakes to the cntl Appalachians, while its associated
ridge will extend throughout the Middle and South Atlantic states.
Dry and cool nly to nnely flow, including a noticeable breeze with
gusts into the 15-20 kt range from mid-morning to early afternoon
focused over the ern half of cntl NC, will result, followed by
mainly calm tonight.

Despite the aforementioned deep subsidence and likely cloud-free
sky, temperatures today will only reach the mid 60s northeast to lwr
70s southwest, followed by strong radiational cooling and lows mostly
in the upr 30s to lwr 40s.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
As of 340 AM Thursday...

A longwave ridge will progress ewd and reach the Middle Atlantic by
12Z Sat. It will do so downstream of a TUTT low that will continue
to circumnavigate the sub-tropical high situated over the srn Plains
in recent days and lift from cntl Mexico this morning to the OH
Valley and srn Middle Atlantic by 12Z Sat. This feature will be
accompanied by a shield of cirrostratus that will overspread cntl NC
later Fri and especially Fri night.

At the surface, Canadian high pressure will drift ewd and across the
Middle Atlantic and Carolinas. Associated light and variable wind
Fri will become calm Fri night.

While temperatures Fri will be near persistence ones in the mid 60s
to lwr 70s, Fri night lows will probably be several degrees milder
than Fri morning owing mostly to the presence of the aforementioned
high-level ceilings.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 400 AM Thursday...

Saturday will be dry and sunny as the mid/upper ridge axis tracks
across the Northeast US and Mid-Atlantic. Temperatures will increase
to slightly above normal as the surface high moves to our east and
off the coast of the Carolinas. Forecast highs range from lower-70s
in the far NE to upper-70s far SW. Cloud cover will begin to
increase on Saturday night as the mid/upper ridge moves offshore and
the flow aloft turns southwesterly ahead of a deep trough that
develops over the MS Valley. Lows will be in the 50s.

In response to the deepening trough aloft, a surface cyclone will
develop and deepen over the Upper Great Lakes region then track into
SE Canada on Sunday and Sunday night. A cold front extending to its
south will move east and cross central NC on Sunday night. So still
have a chance of showers from Sunday afternoon into Sunday night,
with the best chance still looking to be in the evening. However,
reversing the trend from last night, guidance has trended drier
overall. The deterministic GFS and CMC depict zero or very little
precipitation with just a line of showers that dissipates at it
crosses the Appalachians. Their ensemble means are similarly dry,
less than a tenth of an inch. The ECMWF and many of its ensembles
are wetter because they continue to dig a deeper trough and develop
a secondary low over the Mid-Atlantic. But even the ECM ensemble
mean is only a tenth to a quarter inch. Think rainfall amounts will
be limited with the best upper forcing well to our north and overall
progressive nature of the system. The threat of strong storms will
also be hampered by meager instability (less than 500 J/kg of CAPE).
Locally higher amounts of a half to three quarters of an inch would
only be possible with the secondary low scenario, and regardless,
not expecting any hazardous weather or a significant dent in the
ongoing abnormally dry and drought conditions across our region.
Strong WAA ahead of the cold front (SW winds may gust to 20-30 mph)
will help Sunday`s highs get even warmer, in the mid-70s to 80.
Forecast lows Sunday night are in the upper-40s to mid-50s.

Monday will turn sunny and cooler as high pressure builds in behind
the front. NW downsloping flow will bring dew points down into the
30s, and while wind gusts look limited to less than 20 mph, still
can`t rule out some fire weather concerns especially if rain the
previous day is very limited. Forecast highs are in the upper-60s to
lower-70s on Monday with lows in the 40s on Monday night under good
radiational cooling conditions. Uncertainty increases on Tuesday and
Wednesday as another cyclone looks to move from the Upper Great
Lakes into New England, dragging another cold front through our
region. Timing and strength of the low/trough will determine how
much rain we receive, but amounts again look limited at this time.
Temperature forecast confidence is low, but the forecast brings us
slightly warmer Tuesday then slightly cooler on Wednesday behind the
next front.

&&

.AVIATION /11Z THURSDAY THROUGH MONDAY/...
As of 650 AM Thursday...

Canadian high pressure will ridge swd and favor VFR conditions in
cntl NC through the 12Z TAF period, and beyond through at least the
next few days. Nly to nnely flow around the building high will
strengthen and become gusty with daytime heating, probably strongest
and most frequently at FAY; RWI; and RDU, before diminishing to calm
or nearly so this evening.

Outlook: A cold front will move across cntl NC with an accompanying
low VFR to MVFR cloud band and chance of showers Sunday evening.

&&

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

&&

$$

SYNOPSIS...MWS
NEAR TERM...MWS
SHORT TERM...MWS
LONG TERM...Danco
AVIATION...MWS