710
FXUS61 KRNK 300752
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
352 AM EDT Mon Sep 30 2024

.SYNOPSIS...
A large, slow moving low pressure system will move east across
the Mid Atlantic region through Tuesday with periods of
showers. Drier weather returns for Wednesday and Thursday under
high pressure.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 325 AM EDT Monday...

Key Message:

1) Threat of flooding persists today as upper low slowly pushes
into the mountains.

The flood watch this morning will be cancelled as showers have
weakened/dissipated.

The remnants of Helene and the upper low will shift east into
the central Appalachians today while a stalled boundary lingers
across central NC into southeast VA. Better lift to still occur
across our northern CWA and high-res models along with synoptic
models showing overall better coverage toward midday to the
evening across the I-64 corridor and as far south of US 460 in
VA. Rainfall from yesterday came in bands and highest totals
occurred across the VA foothills and piedmont with a secondary
area from Roanoke to Bath County.

Signals from the high-res models and HREF probabilities suggest that
the Alleghanys of VA to the Roanoke Valley southeast to southside VA
could see another set up in terms of showers today. Will have a
flood watch from noon to midnight to cover this area for flooding
but coverage of any flooding will be localized.

Tornadic threat looks to be lower compared to yesterday with poor
lapse rates, but low level helicities of 100+ m2/s2 in the piedmont
could lead to some rotation if convection can get deep enough.
Confidence is low on this as supported by other convective
parameters but it is a non-zero threat.

Look for more clouds than sunshine today with fog and low clouds to
start the day for most. Temperatures will reach the 70s, some 60s in
the mountains.

Tonight, showers will linger through the overnight but gradually
drop off overnight with loss of heating, though having the upper
low/trough overhead showers cannot be ruled out through dawn Tuesday
with higher chances along/north of I-64.

Lows stay above normal in the 60s, except 50s in the mountains.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 330 AM EDT Monday...

Key Message:

1)Tuesday is the last day of shower chances.

Shower chances stay with us into Tuesday but seems better
concentration of lift heads east with the trough weakening, but
enough support with the upper cool pool and residual surface
troughiness to have chance pops in for most. A cold front to
finally start to arrive by late Tuesday night with another upper
trough digging across the Great Lakes to boot what was Helene
east to the coast. By Wednesday should see sunshine returning
and highs in the 70s. Drier air arrives Wed night with
temperatures dropping to the upper 40s to mid 50s in the
mountains to around 60 east.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 230 AM EDT Monday...

Key Messages:

1) Dry conditions will continue through most of the period, with the
only notable chance of rain occurring Friday afternoon.

2) Temperatures will be above normal late week before a cold front
passes through, lowering temperatures back to seasonal averages by
Sunday.

High pressure will be the dominant feature across the Mid-Atlantic
region on Thursday, with quiet weather expected to last into Friday.
A shortwave trough over the Great Lakes region will swing down into
the Ohio River Valley late this week, instigating some lift across
the CWA by Friday afternoon. A mid level ridge just offshore in the
Atlantic will help provide a southerly flow across the CWA. This
will slightly increase mid-level moisture, which along with diurnal
heating and dewpoints in the 60s, will allow enough instability for
some showers and storms to form. On Saturday morning, the trough and
associated cold front move through, but PoPs remain very low during
the passage, as mid-level dry air will suppress any convection.
After the frontal passage, high pressure builds back into the area
for the rest of the weekend, keeping quiet weather in place through
the remainder of the period.

There is high confidence in the precipitation forecast, as high
pressure stays in control for most of the period, with the best
chance of rain coming on Friday afternoon. Temperatures will be
above normal for the late week, as the aforementioned southerly flow
will bring warm air into the region. Highs will be around 80 for the
piedmont, with 70s in higher elevations into the weekend. Lows will
also remain mild, around 60 degrees. Once the front passes,
confidence is moderate that temperatures will return to normal
beginning on Sunday, with highs in the upper 60s to low 70s, and
lows dropping into the upper 40s and low 50s.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
As of 139 AM EDT Monday...

Expect ceilings/some visibilities by mainly IFR at the local
terminals, and below 1 kft for all terminals through much of the
period. Little improvement expected tomorrow with the upper low
in the vicinity and periods of -RA/RA. May see some improvement
to MVFR at DAN but appears low clouds along with numerous
showers to impact most sites Monday afternoon. A stray storm not
out of the question but not enough to warrant taf mention.

Winds through the period will be light and mainly out of the
east to southeast.

Confidence high for the aviation forecast in terms of poor cigs
but lower confidence on vsbys in showers and fog.

Due to a power outage, no data is coming from the BLF ASOS.
AMD NOT SKED has been added to that TAF.

EXTENDED AVIATION OUTLOOK...

Scattered showers remain in the forecast through Tuesday which
may result in MVFR ceilings and visibilities.

Flight conditions should improve Wednesday-Friday as a cold
front crosses the area.

&&

.EQUIPMENT...
As of 1120 AM EDT Sunday...

A power outage has resulted in missing data from the Bluefield
ASOS (KBLF).

The NOAA All-Hazards radio at Richlands is off the air due to
a power outage.

The Hillsville VA (HLX) AWOS is currently out of service with no
estimated time to restored service.

The river gauge on the Watauga River at Sugar Grove will remain
out of service until further notice.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Flood Watch until 6 AM EDT early this morning for VAZ020-024-
     035.
NC...None.
WV...None.

&&

$$

SYNOPSIS...AMS/WP
NEAR TERM...AMS/WP
SHORT TERM...WP
LONG TERM...JCB
AVIATION...SH/WP
EQUIPMENT...AMS/WP