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227
FXUS62 KRAH 031839
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
235 PM EDT Mon Jun 3 2024

.SYNOPSIS...
A series of mid-level disturbances will move east and interact with
a surface trough and unseasonably moist airmass over NC through
Thursday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 945 AM Monday...

As the current surface trough slowly moves across the region
scattered showers continue to move across the eastern portions of
the CWA this morning. Another round of lighter rain is moving across
the Triad area but dissipating as it moves south east. Made minor
changes to the PoPs today as rounds of precipitation is expected
through the day. While chances reduce to 15-25 % for a few hours
during the day, the afternoon chances increase to 25-35% when the
lee trough enters the NW Piedmont later today and moves across the
region this afternoon and evening. While clouds are expected to thin
out later this morning between the features, some areas could see
some sunshine and heating, in result, temperatures ranging around
the low to mid 80s today.

As of 400 AM Monday... Amid an unseasonably moist airmass
characterized by PWs around 1.5" (~90th percentile at GSO), a
tropopause-based disturbance will move from cntl SC esewd and
offshore through 12Z. Meanwhile, an MCV evident in KRAX data over
wrn Chatham Co. will drift slowly, generally ewd and across the ne
NC Piedmont this morning/through ~16Z and across the Coastal Plain
this afternoon/through ~20-21Z.

At the surface, high pressure centered near Bermuda will continue to
extend wwd and across the South Atlantic states. Meanwhile, a lee
trough will sharpen with diurnal heating over the Foothills and wrn
Piedmont of the srn Middle Atlantic and Carolinas, while a sea
breeze will move inland and into the NC Coastal Plain and ern
Sandhills. A weak backdoor cold front will drift south and across
the Delmarva and Chesapeake Bay tonight.

While cloud tops have generally been warming with the area of
convection now moving across west-cntl NC, bursts of cooling and
deepening convection have been noted immediately surrounding the
center of the aforementioned MCV, as it moves east through a weakly
unstable environment over cntl NC. This compact area of convection
will probably be maintained as the MCV continues to move slowly ewd
through the day, and the airmass diurnally warms into the lwr-mid
80s and becomes moderately unstable throughout cntl NC. In the wake
of the MCV, additional, isolated/widely scattered showers/storms are
expected to develop along the lee trough and spread east and across
the wrn Piedmont later this afternoon-evening. A lack discernible
forcing features for tonight suggest today`s convection should
dissipate with nocturnal cooling, with seasonably muggy low
temperatures in the mid/upr 60s.

&&

.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
-- Changed Discussion --
As of 230 PM Monday...

Tuesday should be a relatively average June day with a Bermuda high
in place and southerly return flow beneath weak ridging aloft.  A
weak backdoor cold front is forecast to settle down the Mid-Atlantic
coast but models have trended further north with its final push and
it doesnt quite reach Halifax and Edgecombe Counties, perhaps
stopping over southeast VA per NAM 925mb fields.  Aloft, there is a
weak circulation over TN today but it should drift more
northeastward tonight and doesnt appear to have much impact on
convective development tomorrow.  CAMs tend to slightly favor the
northeast CWA, again perhaps in closer proximity to the weak
convergence associated with the weak backdoor boundary.  PW will
increase to around 1.6, which is around the daily 90th percentile,
and thus will support a little better coverage or storms, which will
be slow moving given very weak tropospheric flow under the ridge.
Will trend 30-50 POPs toward the northeast CWA during the afternoon,
with otherwise partly to mostly cloudy skies once possible morning
stratus in the Piedmont burns off.  Highs will be in the mid to
upper 60s, falling only into the mid and upper 60s overnight with a
continued slight chance of a shower.
-- End Changed Discussion --

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 350 AM Monday...

By Wednesday morning, a stacked low will be over Manitoba, with an
upper trough and surface cold front arcing southeast across
Minneapolis into Illinois and down across the southern Mississippi
River. Both of these features will approach North Carolina during
the day, and have expanded likely pops across the entire forecast
area on Wednesday. Southerly flow will continue to increase, and the
GFS indicates that PW values could approach 2", nearing record
territory. High chance pops will continue into Wednesday night, with
a lobe of energy breaking off both the surface and upper features
and another stacked low forming near Lake Huron by Thursday morning.
Slightly expanded the coverage of likely pops on Thursday, now
covering all areas southeast of US-1, although models are showing
some indecision in how quickly the cold front will move through.
While some parameters depict the front moving east late Thursday
into Thursday night, other parameters show the front bisecting the
region somewhere along the US-1/I-95 corridor Thursday night with a
more definitive push through the region Friday morning. Have
continued with the slight chance pops everywhere Friday afternoon
based on ensemble solutions despite deterministic solutions showing
all precipitation moving to the coast. Dry weather returns to the
forecast for the start of the weekend with dry conditions forecast
Friday night, Saturday, and Saturday night. Another front should
remain west of the region on Sunday, and with a lot of model
uncertainty, only have slight chance pops in the forecast for Sunday.

Thursday should be the warmest day, with highs ranging from the mid
80s to the lower 90s. The Thursday/Friday will only drop
temperatures by a couple degrees, but it will bring a noticeably
drier air mass into the region. The weekend should have highs in the
80s. Lows will mostly be in the 60s, with some upper 50s near the
Virginia border Friday and Saturday nights.

&&

.AVIATION /18Z MONDAY THROUGH Saturday/...
As of 200 PM Monday...

A few isolated showers developing across the region this afternoon
is expected to continue through the early evening before diminishing
later tonight. Scattered to Broken clouds at around 2k-3k feet has
been observed over the Triad for a good part of the day as the lee
trough moves east into the Piedmont. Cloud bases of 3k- 4k ft can be
seen around the Triangle south and east. VFR conditions currently at
most TAF sites are not expected to last as coverage this afternoon
is expected to increase and MVFR conditions are expected to move
into the region this afternoon and evening, some ceiling and visby
restriction conditions are possible with a direct hit at a terminal
, but generally expect MVFR overnight with IFR low stratus
developing early morning especially over the northern terminals.
While the chance for storms across the region remains at around 25-
35%, precip chances will decrease overnight most of Tuesday morning.
Winds will generally be SW 5-10kts this afternoon decreasing to less
than 5 kts overnight. Expect another chance of showers/storms
Tuesday afternoon with day time heating kicking off again.

Outlook: Intermittent Sub-VFR conditions possible as isolated
afternoon and evening showers and thunderstorms anticipated again
Tuesday with more widespread coverage Wednesday as a front moves
through the area. Drier air is expected to move into the region
Friday through the weekend.

&&

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

&&

$$
SYNOPSIS...MWS
NEAR TERM...CA/MWS
SHORT TERM...BLS
LONG TERM...Green
AVIATION...CA