Special Weather Statement, NWS Blacksburg, VA

Area Forecast Discussion
National Weather Service Blacksburg VA
742 PM EDT Tue Aug 31 2021

.SYNOPSIS...
The remnants of Ida will cross the central Appalachians tonight
and Wednesday bringing widespread moderate to heavy rainfall.
High pressure will build in from the northwest for drier and
less humid weather by the weekend.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
As of 735 PM EDT Tuesday...

Storms are showing sporadic signs of rotation this evening given
deep shear as Tropical Depression Ida approaches. As such, a
tornado watch has been issued until 3 am for the Piedmont, as
well as several counties across the mountains. Additional
details will follow shortly.

As of 315 PM EDT Tuesday...

   Wind Advisory issued for Mercer through Watauga Counties.

   Flash Flood Watch in effect for our mountains and foothills
   region this afternoon through Wednesday evening.

Eastern edge of the rainfall will continue to advance northeast
this evening. Hi-Res models bring one band of showers with
embedded pockets of heavy rain and possibly thunder across
southwest Virginia, northwest North Carolina and southeast West
Virginia between 00Z/8pm and 06Z/2AM, followed by the band
closer to the core of Ida which cross southwest to northeast
between 04Z/midnight and 16Z/noon.

Favorable environment in the mountains with the first batch of
rain due to a maximum of 0-1km and 0-3km SRH in the mountains.
Low LCLs also support a tornadic threat. By the time the second
area of showers gets into the foothills and piedmont Wednesday
afternoon, the environment will be more unstable and severe
parameters increase over central Virginia, especially after
18Z/2PM east of Lynchburg and Danville.

No change to the Flash Flood Watch needed at this time. Forecast
rain amounts from the short term models have been consistent
with minor shifts in the location of the axis of heaviest rain.
3 hr Flash Flood guidance has lowered since Monday and rainfall
rates will only increase as precipitable water values climb
tonight and Wednesday.

Bufkit forecasts for Boone and other sites from Bluefield into
the North Carolina mountains show winds of 30 to 40 mph in the
favored downslope areas on the western side of Appalachians. The
direction of the wind is more south-southwest to south-southeast
than southeast, but with wet ground expect to see some downed
trees so Wind Advisory was issued.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
As of 240 PM EST Tuesday...

   Ida high tails it out of here by Wednesday night
   leaving drier conditions to round out the workweek...

Prevailing westerly winds sweep Ida and our upper level trough out
of here fairly quickly late Wednesday night into Thursday morning.
Precipitation looks to end from south to north across the region
late Wednesday evening into the wee hours of Thursday morning. A few
lingering showers may remain over the mountains due in part to
upslope from gusty north to northwesterly flow.

As Ida moves further away from the region Thursday our pressure
gradient will start to relax by late Thursday afternoon as high
pressure builds in. With increased subsidence in the wake of
Ida and incoming high pressure from the Great Lakes region the
door will be left wide open for a plentiful supply of less
humid air to funnel in.

High temperatures as a result will be at or slightly below average
with highs in the low to mid 70s in the west to around 80 out east
on both Thursday and Friday. Overnight lows will also trend down
with an early Fall chill in the air for many on both Thursday and
Friday mornings. Thursday morning lows will be in the mid to
upper 50s for most with widespread low to mid 50s by Friday
morning. Some locations in the mountains west of the Blue Ridge
could wake up to morning lows in the mid to upper 40s by early
Friday morning.

As for any additional flooding concerns from Ida, that is yet
to be seen since it will take time for any mainstem rivers to
respond. We'll continue to monitor this threat over the next
few days ahead although no additional rain is expected in the
short term beyond Thursday morning.

Confidence remains high in the short term period based on model
consistency pulling the remnants of Ida out of the area faster.
Moderate confidence in any additional flooding threat based
upon how rivers respond over the next few days.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 240 PM EDT Tuesday...

   Tranquil weather prevails for much of the Labor Day weekend
   with our next chance of rain early next week...

A large area of high pressure continues to build into the region
from the Upper Great Lakes/Ohio River Valley Friday night and into
the day Saturday. This high will deliver lower humidity values
through the period.

By Sunday, a cold frontal boundary and upper level trough sweeping
in from the Great Lakes region pushes in. The GFS has a weaker front
late Saturday night into Sunday afternoon while the 12z Euro has a
little more bite with precipitation intensity along the boundary
during the same time frame. For now will go with a blend of the two
keeping the highest chances for precipitation along and west of the
Blue Ridge during Sunday afternoon.

The front passes with another area of high pressure settling in
Monday into Tuesday before our next front midweek. Subtle
differences remain in timing and intensity with this boundary
with current 12z guidance hinting on late Tuesday into Wednesday
for precipitation chances to increase again.

Temperatures and humidity look to gradually increase through the
early half of next week. Highs will be back in the in the upper 70s
and low 80s Saturday to mid to upper 80s to start out the first few
days of September. Lows will also stay comfortable with many
locations bottoming out in the mid to upper 50s. Humidity will slow
rise as well but remain in the comfortable range through the holiday
weekend.

Confidence remains moderate to high in the long term period.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
As of 300 PM EDT Tuesday...

Moderate to embedded heavy rain will spread from southwest to
northeast across the Mid Atlantic region this afternoon and
evening. Ceilings will lower to MVFR before 00Z/8PM then down to
LIFR by 06Z/2AM. Little improvement is expected before noon on
Wednesday. Visibility will be MVFR with moderate to heavy rain.

Wind gusts up to 25 knots are possible this afternoon and
evening especially at higher elevations and will increase on the
ridges along the southern Blue Ridge south of Roanoke as high as
40 knots.

Average confidence on all elements this period.

Extended Aviation Discussion...

Tropical moisture and widespread rainfall chances continue
Wednesday afternoon. KLYH and KDAN may have showers or
thunderstorms between noon and 6PM on Wednesday with MVFR
ceilings and visibility.

As the tropical system moves to the northeast, winds will turn
to the northwest with 20 to 30 knot wind gusts at the highest
elevations into Wednesday night/early Thursday. Drier weather
and less humid conditions expected in the wake of Ida Thursday
into the weekend, with VFR conditions, outside any valley fog.

&&

.HYDROLOGY...
As of 330 PM EDT Tuesday...

   Flash Flood Watch remains in effect this afternoon into
   Wednesday evening...

As Tropical depression Ida tracks northeast, surface and low
level winds will turn to the southeast and provide upslope
along the eastern side of the Blue Ridge tonight. Models were
also showing decent upper diffluence tonight and some impressive
precipitation potential placement on Wednesday. System will be
advecting in precipitable water values approaching 2.2 inches by
Wednesday morning. Expect that in any of the bands around the
tropical system rainfall rates may be very heavy. Flash Flood
Guidance has lowered since Monday and expected rainfall over the
Greenbrier Valley, Alleghany highlands and southern Shenandoah
Valley has increased. This increases the Flash Flood threat
along and north of I-64 west of Lexington.

Widespread rainfall amounts of 1 to 3 inches are expected with
locally heavier amounts of 3 to 6 inches possible where any
rain bands set up and persist over a particular area.

Looking at the impact on the main stem rivers, at this time we
are keeping an eye on the Upper James and Greenbrier Rivers for
the potential to reach action stage but, overall impact will be
minimal. This event will have much more impact on the small
rivers, creeks and streams, and in the headwaters than on the
main stems of area rivers.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Flash Flood Watch through Wednesday evening for VAZ007-009>020-
     022>024-032>035.
     Wind Advisory until 8 AM EDT Wednesday for VAZ007-009-015.
NC...Flash Flood Watch through Wednesday evening for NCZ001>004-
     018>020.
     Wind Advisory until 8 AM EDT Wednesday for NCZ001-018.
WV...Flash Flood Watch through Wednesday evening for WVZ042>044-507-
     508.
     Wind Advisory until 8 AM EDT Wednesday for WVZ042.

&&

SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...ET
LONG TERM...ET
AVIATION...AMS/KK
HYDROLOGY...DS/KK

Hazardous Weather Outlook
National Weather Service Blacksburg VA
745 PM EDT Tue Aug 31 2021

NCZ005-006-VAZ043>047-058-059-012345-
Rockingham-Caswell-Henry-Pittsylvania-Campbell-Appomattox-Buckingham-
Halifax-Charlotte-
745 PM EDT Tue Aug 31 2021

...TORNADO WATCH 480 IN EFFECT UNTIL 3 AM EDT WEDNESDAY...

This Hazardous Weather Outlook is for north central North Carolina,
central Virginia and south central Virginia.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

Heavy rainfall, localized flash flooding, and the concern for an
isolated tornado arrives tonight as the remnants of Ida moves in.

   Tornado Watch.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

The threat for heavy rainfall, gusty winds, and isolated tornadoes
associated with the remnants of Hurricane Ida may linger into
Wednesday evening for the Southern Shenandoah Valley and Virginia
Piedmont. The probability of widespread hazardous weather from
Thursday is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Reports should be
submitted by calling 1-866-215-4324, social media, email at
rnk.skywarn@noaa.gov or online at www.weather.gov/rnk.

NCZ004-VAZ011-013-014-016>020-022>024-032>035-012345-
Stokes-Giles-Pulaski-Montgomery-Carroll-Floyd-Craig-Alleghany VA-
Bath-Roanoke-Botetourt-Rockbridge-Patrick-Franklin-Bedford-Amherst-
745 PM EDT Tue Aug 31 2021

...FLASH FLOOD WATCH IN EFFECT THROUGH WEDNESDAY EVENING...
...TORNADO WATCH 480 IN EFFECT UNTIL 3 AM EDT WEDNESDAY...

This Hazardous Weather Outlook is for north central North Carolina,
central Virginia, south central Virginia, southwest Virginia and
west central Virginia.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Tornado Watch.
   Flash Flood Watch.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flash Flood Watch.

The threat for heavy rainfall, gusty winds, and isolated tornadoes
associated with the remnants of Hurricane Ida may linger into
Wednesday evening for the Southern Shenandoah Valley and Virginia
Piedmont. The probability of widespread hazardous weather from
Thursday is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Reports should be
submitted by calling 1-866-215-4324, social media, email at
rnk.skywarn@noaa.gov or online at www.weather.gov/rnk.

NCZ001-018-VAZ007-009-015-WVZ042-012345-
Ashe-Watauga-Tazewell-Smyth-Grayson-Mercer-
745 PM EDT Tue Aug 31 2021

...WIND ADVISORY IN EFFECT UNTIL 8 AM EDT WEDNESDAY...
...FLASH FLOOD WATCH IN EFFECT THROUGH WEDNESDAY EVENING...

This Hazardous Weather Outlook is for northwest North Carolina,
southwest Virginia and southeast West Virginia.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flash Flood Watch.
   Wind Advisory.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flash Flood Watch.
   Wind Advisory.

The threat for heavy rainfall, gusty winds, and isolated tornadoes
associated with the remnants of Hurricane Ida may linger into
Wednesday evening for the Southern Shenandoah Valley and Virginia
Piedmont. The probability of widespread hazardous weather from
Thursday is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Reports should be
submitted by calling 1-866-215-4324, social media, email at
rnk.skywarn@noaa.gov or online at www.weather.gov/rnk.

NCZ002-003-019-020-VAZ010-012-WVZ043-044-507-508-012345-
Alleghany NC-Surry-Wilkes-Yadkin-Bland-Wythe-Summers-Monroe-
Eastern Greenbrier-Western Greenbrier-
745 PM EDT Tue Aug 31 2021

...FLASH FLOOD WATCH IN EFFECT THROUGH WEDNESDAY EVENING...

This Hazardous Weather Outlook is for north central North Carolina,
northwest North Carolina, southwest Virginia and southeast West
Virginia.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

Heavy rainfall, localized flash flooding, and the concern for an
isolated tornado arrives tonight as the remnants of Ida moves in.

   Flash Flood Watch.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flash Flood Watch.

The threat for heavy rainfall, gusty winds, and isolated tornadoes
associated with the remnants of Hurricane Ida may linger into
Wednesday evening for the Southern Shenandoah Valley and Virginia
Piedmont. The probability of widespread hazardous weather from
Thursday is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Reports should be
submitted by calling 1-866-215-4324, social media, email at
rnk.skywarn@noaa.gov or online at www.weather.gov/rnk.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BLACKSBURG VA
945 PM EDT TUE AUG 31 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0636 PM     TSTM WND DMG     2 SW PEORIA             36.26N 81.89W
08/31/2021                   WATAUGA            NC   LAW ENFORCEMENT

            TREE DOWN IN THE 8700 BLOCK OF NC HIGHWAY
            321. TIME ESTIMATED FROM RADAR.

&&

VFJ

Special Weather Statement
National Weather Service BLACKSBURG VA
947 PM EDT Tue Aug 31 2021

VAZ019-020-023-WVZ507-010215-
Botetourt VA-Bath VA-Alleghany VA-Eastern Greenbrier WV-
947 PM EDT Tue Aug 31 2021

...Strong thunderstorms will impact portions of
northeastern Alleghany, Bath, north central Botetourt Counties in
west central Virginia and east central Greenbrier Counties in
southeastern West Virginia and the City of Covington through 1015 PM
EDT...

At 946 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Natural Well to near Eagle Rock. Movement
was north at 50 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Covington...
Clifton Forge...
Warm Springs...
Millboro...
Eagle Rock...
Hot Springs...
and Iron Gate.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

A Tornado Watch remains in effect until 300 AM EDT for central, south
central, southwestern and west central Virginia.

&&

LAT...LON 3822 7971 3821 7959 3814 7952 3795 7959
      3793 7961 3788 7965 3786 7962 3774 7969
      3770 7968 3752 7974 3788 8013 3805 8012
      3806 7996 3810 7993 3813 7995 3815 7992
      3818 7992 3827 7980
TIME...MOT...LOC 0146Z 187DEG 61KT 3790 8006 3762 7975

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

WP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BLACKSBURG VA
953 PM EDT TUE AUG 31 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0718 PM     TSTM WND DMG     4 ENE BLACKSBURG        37.26N 80.35W
08/31/2021                   MONTGOMERY         VA   911 CALL CENTER

            TREE DOWN PARTIALLY BLOCKING CATAWBA ROAD.
            TIME ESTIMATED FROM RADAR.

&&

VFJ

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BLACKSBURG VA
959 PM EDT TUE AUG 31 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0814 PM     TSTM WND DMG     1 E BLACKSBURG          37.23N 80.41W
08/31/2021                   MONTGOMERY         VA   911 CALL CENTER

            TREE DOWN NEAR INTERSECTION OF ROANOKE AND
            JEFFERSON STREET, PARTIALLY BLOCKING THE
            ROADWAY. TIME ESTIMATED FROM RADAR.

&&

VFJ

Special Weather Statement
National Weather Service BLACKSBURG VA
1026 PM EDT Tue Aug 31 2021

VAZ024-035-010300-
Amherst VA-Rockbridge VA-
1026 PM EDT Tue Aug 31 2021

...A strong thunderstorm will impact portions of
central Rockbridge and northwestern Amherst Counties, the City of
Buena Vista and the City of Lexington through 1100 PM EDT...

At 1025 PM EDT, Doppler radar was tracking a strong thunderstorm over
Snowden, or over Glasgow, moving north at 25 mph.

HAZARD...Wind gusts up to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Lexington...
Buena Vista...
Glasgow...
Alto...
Cornwall...
and Oronoco.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

A Tornado Watch remains in effect until 300 AM EDT for central, south
central and west central Virginia.

&&

LAT...LON 3783 7916 3782 7916 3755 7935 3756 7937
      3759 7938 3761 7941 3760 7943 3758 7945
      3760 7944 3762 7944 3761 7945 3790 7948
TIME...MOT...LOC 0225Z 194DEG 20KT 3761 7940

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

WP

Special Weather Statement
National Weather Service BLACKSBURG VA
1030 PM EDT Tue Aug 31 2021

VAZ023-024-010300-
Botetourt VA-Rockbridge VA-
1030 PM EDT Tue Aug 31 2021

...A strong thunderstorm will impact portions of
southwestern Rockbridge and northeastern Botetourt Counties through
1100 PM EDT...

At 1030 PM EDT, Doppler radar was tracking a strong thunderstorm over
Buchanan, moving north at 20 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Buchanan...
Natural Bridge...
and Arcadia.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

A Tornado Watch remains in effect until 300 AM EDT for central, south
central, southwestern and west central Virginia.

&&

LAT...LON 3771 7945 3745 7963 3746 7964 3747 7964
      3748 7965 3748 7968 3745 7972 3745 7973
      3775 7975
TIME...MOT...LOC 0230Z 194DEG 19KT 3748 7967

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

WP