355
FXUS61 KRNK 071409
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
1009 AM EDT Sun Jul 7 2024

.SYNOPSIS...
A front will waver across central and eastern Virginia and North
Carolina through the week. The chance of showers and thunderstorms
will continue each day. Unseasonably warm and humid weather will
also remain over the region.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1000 AM EDT Sunday...

Key message:

    - Highest confidence for thunderstorms across North Carolina and
      southern Virginia this afternoon and evening


Showers continue in an widely scattered fashion across the NC
piedmont into southside VA. The latest HRRR has a pretty good
handle but still not enough coverage. PWATS this morning have
risen to 2.12 at GSO and 1.36 at RNK.

There is a bubble of moisture increasing from the southeast per
loop of MSAS, with inverted trough across the upper TN Valley,
with actual front stretching from the Tidewater of VA west-
southwest through central NC. This configuration may allow for a
little more lift swinging into southern VA this afternoon, with
also some low level convergence along the southern Blue Ridge
into the upper TN valley where isolated storms are possible, so
a little more coverage than Saturday but still ranging from
isolated/widely scattered from Bluefield-Blacksburg-Farmville,
to better coverage south of the VA/NC border, and moreso in the
NC mountains. With pwats this high, will have to watch for
localized flooding issues as thunderstorms with be proficient
rain makers and slow movers.

Previous discussion...

Front will remain stalled over the region today. Surface dew points
were in the 70s on the east side of the boundary. Guidance has the
front drifting back to the eastern slopes of the Blue Ridge today,
allowing those higher dew points to expand northwest. The hottest
heat index will be in the  95 to 100 degree range in the foothills and
piedmont around 4PM.

A majority of the convective allowing models show scattered to
numerous thunderstorms along and south of the Virginia/North
Carolina border, mainly after 2PM. More questionable is the coverage
of thunderstorms along the low level convergence with the front.
Convective Available Potential energy is forecast to be in the 500-
1000 J/kg and shear is minimal, so no organized threat of severe
thunderstorms anticipated. Isolated flash flooding is possible,
especially southeast of the front where rainfall rates could be the
2-4 in/hour. These rates are supported by precipitable water values
of 1.7 to 2.3 inches, above 2 standard deviations above normal.

The abundant moisture will also contribute to mild temperatures
overnight. Most locations on the southeast side of the front will
not drop below 70 degrees.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 500 AM EDT Sunday...

Key Messages:

1: Diurnally driven showers early this week

2: Showers could have high rain rates

A nearly stationary front in the Mid-Atlantic will continue the
process of losing its boundary characteristics. However, southerly
flow will continue to advect in anomalously warm moist air. PWATs of
1.75-2.25" around the area will be at least a couple standard
deviations above normal according to NAEFS situational awareness
tool. Even in the middle of July, a PWAT of 2" in Danville is quite
a lot of moisture. With such a moisture laden atmosphere, even with
the loss of frontal boundary forcing, scattered diurnal showers will
be wont to form throughout our CWA. In addition to the excessive
atmospheric moisture, model soundings depict tall skinny CAPE
profiles, which are generally indicative of efficient rain
processes. Localized flooding will be a concern as we monitor any
showers that do form, because of the potential for high rain rates.

It will also be anomalously warm, with highs each day in the upper
80s and mid 90s east of the Blue Ridge, and in the 80s west. This
will make for rather uncomfortable outdoor conditions in the
Piedmont and Southside, where heat indices will likely reach 100-
103F during the afternoons.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 500 AM EDT Sunday...

Key Message:

1: Diurnal showers and storms continue

There won`t be much change in the overall weather pattern for us on
the east coast over the course of this week. Broad troughing to our
west, and a stout Bermuda High on the east will ensure that we
continue to receive warm moist advection. The only feature that will
be out of the norm is the washed up remains of Beryl. By the time
that Beryl reaches the Ohio Valley, it will have weakened enough
that its unlikely we receive any wind impacts. What could happen
though, is another infusion of atmospheric moisture. As such, expect
temperatures to be above normal, and diurnal showers and storms to
form each afternoon and evening.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
As of 655 AM EDT Sunday...

Mainly VFR with scattered to broken mid and high clouds through
16Z/noon.

Front will remain stalled over the region today. A majority of
the convective allowing models show scattered to numerous
thunderstorms along and south of the Virginia/North Carolina
border, mainly after 2PM. Thunderstorms have the potential for
MVFR ceilings and MVFR or lower visibility due to very heavy
rain. More questionable is the coverage of thunderstorms along
the low level convergence with the front.

The most likely TAF site to have thunderstorms will be KDAN.

Average confidence for ceiling, visibility, wind.
Average confidence for timing and location of thunderstorms this
afternoon and evening.


AVIATION OUTLOOK...

Little change in the weather pattern and location of the front
is expected through the rest of the week. This will result in a
daily threat of thunderstorms, mainly in the afternoon and
evening.

Prevailing conditions will be VFR. The exception will be brief
periods of IFR/MVFR with the thunderstorms and also with
overnight fog.

&&

.CLIMATE...
As of 520 AM EDT Sunday...

Records for the warmest minimum temperatures may be set at
Blacksburg on Monday and Tuesday.

Tuesday looks to be the warmest day of the week so those records
have been listed here.


July 7th
Site  MaxT Year  MinT Year  LoMax Year  HiMin Year
KBLF    93 2012    44 1951     65 1967     73 1998
KDAN   104 2010    55 1979     76 1961     78 1921
KLYH   100 2012    52 2001     72 2005     75 1977
KROA   102 2012    48 1983     74 2005     78 1977
KRNK    94 2010    41 1972     67 1967     67 2022

July 8th
Site  MaxT Year  MinT Year  LoMax Year  HiMin Year
KBLF    93 2012    45 1951     70 1947     71 1977
KDAN   103 2012    54 1979     74 1949     78 1930
KLYH   101 2012    53 1983     68 1918     75 2022
KROA   102 2012    50 1979     74 1949     77 2012
KRNK    96 1988    42 1896     67 1896     70 1941

July 9th
Site  MaxT Year  MinT Year  LoMax Year  HiMin Year
KBLF    92 2007    42 1918     63 1979     75 1994
KDAN   103 1977    52 2018     69 1950     76 1987
KLYH   102 1936    53 2018     66 1927     74 1992
KROA   101 1936    48 1918     68 1969     77 1992
KRNK    97 1988    42 1961     67 1927     67 1939

&&

.EQUIPMENT...
As of 520 AM EDT Sunday...

KFCX Radar is degraded...Horizontal Low Noise Amplifier is INOP,
damaged by thunderstorm.  Please use data with caution.
High reflectivity above 40 dbz appears OK, but the radar is unable
to detect and lower reflectivity. A Low Noise Amplifier has
been emergency ordered.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.

&&

$$

SYNOPSIS...AMS
NEAR TERM...AMS/WP
SHORT TERM...VFJ
LONG TERM...VFJ
AVIATION...AMS/PM
CLIMATE...AMS
EQUIPMENT...PM