-- Discussion containing changed information from previous version are highlighted. --
670
FXUS61 KRNK 071751
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
151 PM EDT Tue May 7 2024

.SYNOPSIS...
The weather pattern will remain unsettled for much of the
week with a daily threat of afternoon and evening
thunderstorms through Thursday. Cooler and drier weather returns
by the weekend.

&&

.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
As of 1040 AM EDT Tuesday...

Key Message:

1. Potential thunderstorms this afternoon and evening,

Most of the remaining few morning showers have moved out of the
area at this time. Ample cloud cover persists along and west of
the Blue Ridge, while some larger breaks in the clouds are
present over the Foothills and Piedmont. Expecting a decreasing
trend in cloud cover for the next few hours, before coming back
in with some afternoon showers and thunderstorms. Morning
sounding at RNK showed west to northwesterly winds near the
surface and aloft, so confidence is still lower on storm
coverage at this time, with westerly flow limiting storm
potential. No changes made to the forecast for this morning
update, aside from blending in current observations.

Previous discussion below...


As of 220 AM EDT Tuesday...

Upper wave responsible for the rain/storms yesterday will move
off the Mid-Atlantic coast this morning and weak ridging builds
overhead. Will see an increase in westerly winds behind the
departing wave. Still a bit of uncertainty on storm coverage
today with the upper ridging and westerly flow that will be in
place, which tends to suppress storm development. HRRR, NAM, and
multiple renditions of the WRF all indicate very spotty
coverage today as well. With this is mind, kept the PoPs highest
over the western mountains really decreased chances east of the
mountains. May have late development as the westerly wind
relaxes late this evening, but will begin to lose instability by
that point as we lose daytime heating. However, any storm that
is able to develop will have the potential for damaging winds,
especially with modeled DCAPE over 1000 J/kg by the mid-
afternoon.

Expecting any convection to quickly diminish after sunset and
may have areas of fog develop again tonight. Low a bit warmer in
the mid to low 60s.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
As of 430 AM EDT Tuesday...

Key Messages:

   - Increasing flash flood threat
   - Periods of numerous showers and thunderstorms

Mid-level troughing deepens on Wednesday ahead of a frontal
passage on Thursday. Both days will feature showers and
thunderstorms across the entire forecast area. Due to the
antecedent conditions and multiple consecutive days of
convective showers and storms, the threat for flash flooding
will increase through the week. High rainfall rates are possible
within any storms that form due to the above normal PWATs. There
is potential for thunderstorms to exhibit severe
characteristics, especially during the peak heating periods of
each afternoon. Greatest threats will be damaging winds or
large hail.


An embedded shortwave rotating through a broader trough will
continue the pattern of thunderstorms and rainshowers on Friday
as well. Temperatures will be around normal or just below thanks
to cloud cover, the cooling effects of showers and storms, and
frontal passage on Thursday.

&&

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

Key Messages:

  - Temperatures cool off
  - Daily threat of thunderstorms continues

Overall synoptic scale pattern during this time frame features broad
troughing in the eastern United States and lower 5000 MB heights. No
particular focus to aid in development of precipitation but region
remains cooler than earlier in the week, but warm enough for a daily
chance of afternoon and evening showers and thunderstorms. For now,
enough of a break from the deep moisture to the forecast for Monday
dry.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
As of 150 PM EDT Tuesday...

Mostly VFR to MVFR conditions presently observed across the
area. A few isolated showers have begun to pop up in far
southwestern VA and northwest NC. Expecting only isolated to
scattered coverage of showers and thunderstorms today, coverage
limited by the westerly winds at the surface and aloft. Greatest
chances for storms are over the mountains, so have included
VCTS for KLWB, KBLF, and KBCB. Storms that do develop this
afternoon and evening have the potential to produce damaging
wind gusts and hail. Coverage of showers and storms will
decrease after sunset, and any lingering showers should diminish
after midnight.

Ceilings lower to sub-VFR Wednesday morning west of the Blue
Ridge, improving after sunrise. Otherwise, ceilings east of the
mountains should remain VFR through the TAF period. Reductions
in visibilities from patchy fog are possible again for a few
hours during the morning hours given ample moisture and clearer
skies in the east. Patchy fog is also possible in the valleys,
like KLWB and KBCB.

Winds turn southwesterly later Tuesday evening, and will be
west-southwesterly through Wednesday at 5 to 10 knots. Winds
gusts may reach 15 to 20 knots this afternoon across the higher
elevations, and again Wednesday afternoon.

Forecast confidence is average.

Extended Aviation Outlook...

Unsettled weather is expected for much of the week. Daily
threat of SHRA/TSRA through at least Friday. This will bring
periods of MVFR/IFR ceilings and visibilities at times. Winds
through Wednesday will favor a SW direction and may be gusty at
times.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...BMG
NEAR TERM...AS/BMG
SHORT TERM...VFJ
LONG TERM...AMS/VFJ
AVIATION...AS/BMG