911
FXUS62 KRAH 201027
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
627 AM EDT Sun Apr 20 2025

.SYNOPSIS...
A backdoor cold front will drop through Virginia and into northern
North Carolina today, then linger across northern North
Carolina tonight and return north into the Middle Atlantic as a
warm front on Monday. A slow moving and weakening cold front
will move east into the Carolinas Monday night and Tuesday and
then stall across the region through much of the work week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 345 AM Sunday...

* Continued unseasonably warm

Aloft, the mid-level anticyclone will remain over/just off the
Southeast US coast, ridging nwd along the Carolina/srn mid-Atlantic
coast, through tonight. Meanwhile, the H5 low (over NM as of 06Z)
will shift ewd into the srn Plains this morning, then lift nnewd
across the cntl Plains and into the upper MS Valley through tonight.
At the surface, a backdoor cold front will slide swd across the mid-
Atlantic and into northeast NC through this evening, then stall over
the Coastal Plain and nrn Piedmont tonight. Meanwhile, the Bermuda
high will retreat wwd toward the Southeast US coast as the Canadian
high continues ewd across srn Ontario, Quebec, and the Northeast US
today into tonight, the backdoor front situated between the two
highs. Still expect an area of moisture convergence along the
backdoor front, with localized dewpoints temps in the low to mid
60s. Forecast soundings do show some MLCAPE (highest (~1000 J/Kg)
off the NAM at KRDU and KRWI), however much of that instability
resides above a capping inversion, which for now seems to hold. With
the moisture and instability present, cannot rule out a stray shower
along the front, but chances remain low at this time. Skies should
generally remain cloudy today and tonight, however highs should
still be similar to Sat, in the mid 80s. Lows tonight will be
continued mild, upper 50s to low 60s. There could be a brief period
of some gusts of 15-20 mph along and in the wake of the front this
evening, otherwise expect winds of 5-10 kts, generally swly to
ssely.

&&

.SHORT TERM /MONDAY AND MONDAY NIGHT/...
As of 400 AM Sunday...

Aloft, the mid-level cyclone will lift nwd across the wrn Great
Lakes and srn Ontario, Canada, while the anticyclone weakens off the
east coast of FL. At the surface, the front will lift newd out of
the area on Mon, with a Piedmont trough setting up Mon eve as a cold
front approaches the Appalachians from the west. As the parent low
occludes over se Canada Mon night, the attendant cold front will
become more WSW-ENE oriented as it moves across the mid-Atlantic.
The weather should largely remain dry Mon and most of Mon night.
Expect showers to approach from the west late Mon night, moving into
the NW Piedmont Tue morn. Winds could become a bit breezy again on
Mon as the pressure gradient increases ahead of the front, with
gusts of 15-20 mph, highest over the northwest Piedmont Mon aft/eve.
Otherwise, expect another unseasonably warm day, with highs in the
low to mid 80s and lows in the low to mid 60s.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 310 AM Sunday...

* High temperatures will be well above normal on Tuesday and
  slightly above normal for the rest of the period.
* A weakening front will move into the area on Tuesday and linger
  for much of the work week providing a weak focus for scattered
  showers and a few storms.
* Rainfall totals for Tuesday through Saturday will average around a
  half inch with somewhat greater amounts across southern areas.

The long term period begins on Tuesday morning with an exiting mid
and upper-level closed low across Quebec and a weakened ridge just
east of FL. The remnants of a sheared out trough will extend from
the Chesapeake Bay southwest across the western Carolinas into the
Deep South. An associated surface cold front which will be weakening
drops into the western Carolinas Monday night and moves into the
central Carolinas on Tuesday and Wednesday and then waivers and
dissipates on Thursday and Friday.

Deep layer moisture will increase with the southwesterly flow aloft
resulting in PW values increasing to around 1.5 inches across
central NC late Tuesday and into Wednesday. The enhanced moisture
persists and may moisten further on Thursday and Friday. While the
forcing won`t be particularly strong, low-level convergence along
the front, increasing moisture, and some modest low level
instability will support shower/thunderstorm chances across central
NC for the Tuesday through Friday period. The greatest PoPs in the
50% range are focused on Wednesday and perhaps Thursday with the
precipitation chances greatest during the afternoon and evening. A
slight enhancement to the mid level flow will support bulk-layer
shear values of 20 to 30 kts mainly for Wednesday through Friday
which could result in a stronger storm or two but no widespread
organized severe weather is expected during the period. Rainfall
totals through Friday night will average around a half inch with
slightly greater amounts probable across southern areas in the
southern Piedmont and Sandhills where greater instability and
moisture is expected.

High temperatures will be the warmest on Tuesday with highs in the
lower to mid 80s which is about 8 to 12 degrees above average. Highs
will drop back a bit on Wednesday and Thursday and range in the
upper 70s to lower 80s which is about 4 to 8 degrees above average.
Lows will range mainly in the upper 50s to lower 60s.

the next mid and upper level trough develops across the Midwest and
Great lakes on Friday and approaches the Carolinas on Saturday. An
associated cold front will also approach the area with enhanced
moisture and some stronger flow which will support an uptick in
shower and storm coverage. Highs will nudge upward ahead of the
front and range in the lower to mid 80s on Saturday. -Blaes

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
As of 625 AM Sunday...

24 hour TAF period: High confidence VFR conditions will prevail,
with broken high clouds, through the TAF period. The exception is
some MVFR cigs developing invof KRWI after 08Z Mon. A backdoor cold
front will slip swd-swwd into the area today, with winds becoming a
bit more sly across the area ahead of it and more variable along, to
sely to ely and potentially gusty (15-20 kts) behind it this
eve/tonight (mainly at KRWI and KRDU).

Outlook: MVFR cigs should retreat newd out of the area Mon morn.
There could be some borderline LLWS Mon eve/night as the LLJ
strengthens to around 35 kts as it passes over central NC. There
will be a chance for convection and flight restrictions Tue-Thu as a
cold front moves into and settles over the area.

&&

.CLIMATE...
Record High Temperatures:

April 20:
KGSO: 94/1917
KRDU: 93/1896
KFAY: 94/1917

Record High Minimum Temperatures:

April 20:
KGSO: 65/1941
KRDU: 67/1896
KFAY: 69/2011

April 21:
KGSO: 64/1927
KRDU: 70/1896
KFAY: 68/2017

April 22:
KGSO: 63/1967
KRDU: 66/1909
KFAY: 64/1963

&&

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

&&

$$

SYNOPSIS...Blaes
NEAR TERM...KC
SHORT TERM...KC
LONG TERM...Blaes
AVIATION...KC
CLIMATE...RAH