Special Weather Statement, NWS Blacksburg, VA

Area Forecast Discussion
National Weather Service Blacksburg VA
246 PM EDT Mon Aug 6 2018

.SYNOPSIS...
High pressure was centered over the southeastern United States
providing typical summer weather conditions with a daily threat
for mainly afternoon and evening thunderstorms and near
seasonal temperatures. A weak cold front will approach from the
west Wednesday bringing a better chances for organized storms
to the region.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 245 PM EDT Sunday...

An upper level low off the Virginia coast will provides
subsidence to areas east of the Blue Ridge, primarily north of
Mount Airy to Danville, keeping dry conditions through Tuesday
afternoon. As deep westerly flow subsides while the low move
further offshore late tomorrow afternoon, a lee trough and
diurnal heating will generate scattered showers and
thunderstorms into the evening. Other than a few thunderstorms
tomorrow afternoon, the only weather hazards for the foothills
and piedmont counties will be patchy dense fog along the rivers
in the morning and warm humid conditions with heat indices in
the mid to upper 90s in the afternoon.

The mountains will have a better chance to see showers this
evening and again tomorrow afternoon. A stationary upper level
ridge, situated over the southeastern Gulf states, has stretched
northward into the southern Ohio Valley today. The outer ring
of this ridge sits over southwest Virginia (Bluefield) to the
northwest North Carolina mountains/foothills. A weak wave with a
cluster of storms will track across this area this afternoon
then dives south into western North Carolina late this afternoon
and evening. Any orographical showers across the rest of the
mountains will fade with lose of heating this evening. Models
are not showing any waves coming around the ridge overnight,
therefore lowered PoPs across the area after midnight. Storms
this afternoon/evening are capable of producing heavy downpours
which could lead to localized flooding. There is also a threat
that any storms forming this afternoon could also produce wet
microburst. The threat level for flooding or severe weather is
low, but not zero. Patchy dense fog is likely along the rivers
of the Greenbrier and New River Valleys and also in area that
see rain today.

The southeast Gulf coast ridge remains stationary tomorrow but
becomes flat across the southern Ohio Valley into Virginia.
There does not appear to be any waves coming across the
mountains tomorrow, however moisture and instabilities increase
as a cold front approaches the region. With an uptick in
ingredients for storms Tuesday afternoon, more areal coverage of
showers and thunderstorm are expected west of the Blue Ridge.
Storms will likely track west to east and again have the
capability to produce heavy downpours and/or wet microbursts.

Temperatures will be a few degrees above normal tonight into
Tuesday. Overnight lows will remain muggy from the 60s west of
the Blue Ridge to the low 70s east. Highs across the mountains
will warm into the 80s with low 90s east.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
As of 150 PM EDT Monday...

500 MB heights begin to lower on Wednesday with a short wave
reaching the area late in the day. Will be well into the right
rear quadrant of a 60 knot upper jet by that time. A bulk of the
lift will be offshore by late Thursday. Consensus of guidance
does not show much change in temperatures but surface dew points
will be dropping for Thursday.

850MB winds are out of the west even ahead of the front which
will result in the better coverage of showers and thunderstorms
over the mountains. Significant differences in the GFS and
particularly the NAM are suggesting a pre-frontal line of
showers and thunderstorms that crosses the mountains and
foothills and will be east of Lynchburg and Danville by evening,
but showed significant difference in the amount of placement of
low level moisture behind the front on Thursday. Threat for
severe thunderstorms is marginal based on expected instability
and shear but probability of heavy rain remains due to
precipitable water values again approaching two inches.

Confidence was average for all elements, with the exception of
clouds and temperatures on Thursday which is below average.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
As of 155 PM EDT Monday...

Synoptic scale pattern becomes more amplified by Saturday with
a closed upper low forming somewhere in the vicinity of the Ohio
Valley by the end of the weekend. This puts the Mid Atlantic
region in southwest flow Saturday through Monday with short wave
energy coming through the base of the trough into the area on
Saturday. No big deviations planned from the blended guidance.
Temperatures will be near to slightly above normal this time
frame.

Confidence was average for all elements Friday and below
average on Saturday through Monday.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
As of 130 PM EDT Monday...

Generally VFR through the 24 hour TAF period, with the
following two exceptions...

Daytime heating and cloud buildups over the mountains will
result in widely scattered SHRA/TSRA from 18Z/2PM-00Z/8PM.

Development of mountain/river valley fog between 06Z/2AM-
daybreak along the rivers with high probability of LIFR at KLWB
and KBCB. Elsewhere fog expected to be patchy ground fog.

Winds through the period generally light and variable except
for outflow near shra/tsra.

Extended...

Summer pattern will feature mainly VFR. Any sub-VFR will be
associated with scattered mainly afternoon and evening shra/tsra
and development of early morning fog/stratus in the mountain
valleys...all of which are temporary.

Best coverage of storms will occur mid-week (Wednesday)
associated with an upper level trof and weak surface cold front.
The fog/stratus should be limited to pre-dawn hours and
confined mainly to the mountain river valleys with impacts to
KBCB/KLWB.

&&

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

&&

SYNOPSIS...RCS
NEAR TERM...RCS
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...RCS

Hazardous Weather Outlook
National Weather Service Blacksburg VA
439 AM EDT Mon Aug 6 2018

VAZ007-010>014-016>020-022>024-032>035-043>047-058-059-WVZ042>044-
507-508-070845-
Tazewell-Bland-Giles-Wythe-Pulaski-Montgomery-Carroll-Floyd-Craig-
Alleghany VA-Bath-Roanoke-Botetourt-Rockbridge-Patrick-Franklin-
Bedford-Amherst-Henry-Pittsylvania-Campbell-Appomattox-Buckingham-
Halifax-Charlotte-Mercer-Summers-Monroe-Eastern Greenbrier-
Western Greenbrier-
439 AM EDT Mon Aug 6 2018

This Hazardous Weather Outlook is for central Virginia, south
central Virginia, southwest Virginia, west central Virginia and
southeast West Virginia.

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

A weather disturbance is expected to move east through the area on
Wednesday. Scattered showers and thunderstorms are expected to
develop in advance of this system. Some of the strongest storms may
produce locally damaging winds. The greatest potential for severe
weather on Wednesday will be during the afternoon and evening hours,
mainly along and north of Highway 460.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

NCZ001>006-018>020-VAZ009-015-070845-
Ashe-Alleghany NC-Surry-Stokes-Rockingham-Caswell-Watauga-Wilkes-
Yadkin-Smyth-Grayson-
439 AM EDT Mon Aug 6 2018

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

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Wert

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BLACKSBURG VA
326 PM EDT MON AUG 6 2018

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

0300 PM     HAIL             2 NNW BOONE             36.23N 81.68W
08/06/2018  E0.50 INCH       WATAUGA            NC   TRAINED SPOTTER

            PEA TO DIME SIZED HAIL

&&

LOCONTO

Special Weather Statement
National Weather Service BLACKSBURG VA
329 PM EDT MON AUG 6 2018

VAZ010-011-013-WVZ042-062015-
Giles-Pulaski-Bland-Mercer-
329 PM EDT MON AUG 6 2018

...A STRONG THUNDERSTORM WILL AFFECT
NORTHWESTERN PULASKI...SOUTHWESTERN GILES...NORTHEASTERN BLAND AND
SOUTHEASTERN MERCER COUNTIES...

Until 415 PM EDT.

At 329 PM EDT, a strong thunderstorm was located over Chapel, moving
southeast at 5 mph.

Winds in excess of 40 mph and half inch hail are possible with this
storm.

Locations impacted include...
Pearisburg...
Narrows...
Poplar Hill...
Oakvale...
and Glen Lyn.

Torrential rainfall is also occurring with this storm, and may cause
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.

LAT...LON 3730 8109 3742 8091 3726 8061 3706 8084
TIME...MOT...LOC 1929Z 312DEG 6KT 3729 8091

Loconto

Special Weather Statement
National Weather Service BLACKSBURG VA
346 PM EDT MON AUG 6 2018

VAZ017-032-062030-
Patrick-Floyd-
346 PM EDT MON AUG 6 2018

...A STRONG THUNDERSTORM WILL AFFECT
CENTRAL FLOYD AND NORTH CENTRAL PATRICK COUNTIES...

Until 430 PM EDT.

At 345 PM EDT, a strong thunderstorm was located near Mabry Mill,
moving northeast at 10 mph.

Winds in excess of 40 mph and half inch hail are possible with this
storm.

Locations impacted include...
Floyd...
Willis...
Meadows Of Dan...
Mabry Mill...
and Rocky Knob Recreation Area.

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

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.

LAT...LON 3677 8051 3682 8055 3701 8040 3702 8038
      3702 8036 3693 8019 3691 8020 3669 8039
TIME...MOT...LOC 1945Z 218DEG 10KT 3681 8042

Loconto

Special Weather Statement
National Weather Service BLACKSBURG VA
406 PM EDT MON AUG 6 2018

NCZ004-005-062045-
Stokes-Rockingham-
406 PM EDT MON AUG 6 2018

...A STRONG THUNDERSTORM WILL AFFECT
EASTERN STOKES AND WESTERN ROCKINGHAM COUNTIES...

Until 445 PM EDT.

At 406 PM EDT, a strong thunderstorm was located over Danbury, moving
east at 15 mph.

Winds in excess of 40 mph and half inch hail are possible with this
storm.

Locations impacted include...
Mayodan...
Madison...
Walnut Cove...
Stoneville...
and Danbury.

Torrential rainfall is also occurring with this storm, and may cause
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.

LAT...LON 3641 8035 3654 8029 3654 8025 3648 7985
      3626 7997 3626 8003
TIME...MOT...LOC 2006Z 291DEG 12KT 3645 8022

Loconto

Special Weather Statement
National Weather Service BLACKSBURG VA
420 PM EDT MON AUG 6 2018

VAZ009-015-062100-
Grayson-Smyth-
420 PM EDT MON AUG 6 2018

...A STRONG THUNDERSTORM WILL AFFECT
SOUTHEASTERN SMYTH AND NORTHWESTERN GRAYSON COUNTIES...

Until 500 PM EDT.

At 420 PM EDT, a strong thunderstorm was located over Thomas Bridge,
moving east at 10 mph.

Winds in excess of 40 mph and pea size hail are possible with this
storm.

Locations impacted include...
Marion...
Sugar Grove...
Mount Rogers National Recreation Area...
Troutdale...
and Adwolf.

Torrential rainfall is also occurring with this storm, and may cause
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.

LAT...LON 3682 8165 3688 8132 3682 8128 3662 8127
      3667 8164 3673 8167
TIME...MOT...LOC 2020Z 266DEG 8KT 3675 8157

Loconto

Special Weather Statement
National Weather Service BLACKSBURG VA
437 PM EDT MON AUG 6 2018

WVZ042-043-062115-
Mercer-Summers-
437 PM EDT MON AUG 6 2018

...A STRONG THUNDERSTORM WILL AFFECT SOUTHERN SUMMERS AND
NORTHEASTERN MERCER COUNTIES...

Until 515 PM EDT.

At 436 PM EDT, a strong thunderstorm was located over Lerona, moving
northeast at 10 mph.

Winds in excess of 30 mph and pea size hail are possible with this
storm.

Locations impacted include...
Athens...
Pipestem...
Buck...
Pipestem Resort State Park...
and Lick Creek.

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 3761 8073 3752 8080 3743 8085 3738 8100
      3751 8108 3772 8082
TIME...MOT...LOC 2036Z 234DEG 8KT 3748 8096

RAB