SPC Sep 22, 2023 0730 UTC Day 3 Severe Thunderstorm Outlook

SPC Sep 22, 2023 0730 UTC Day 3 Severe Thunderstorm Outlook

SPC 0730Z Day 3 Outlook
Day 3 Outlook Image
Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0219 AM CDT Fri Sep 22 2023

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN PLAINS...

...SUMMARY...
Thunderstorms, associated with large hail and wind damage, will be
possible on Sunday from parts of central Texas northeastward into
southeast Oklahoma.

...Southern Plains/Ark-La-Tex...
A shortwave trough is forecast to move eastward across the southern
Plains on Sunday. A cold front will likely advance southward into
west-central and north Texas by afternoon. Warming surface
temperatures ahead of the front will result in moderate to strong
destabilization by afternoon, with MLCAPE expected to peak in the
2000 to 3000 J/kg range in many areas south of the front. As
instability and low-level convergence increase near the front,
scattered thunderstorms will likely form in the mid to late
afternoon. These storms will move southeastward into the stronger
instability across north-central and northeast Texas, with several
cell clusters persisting into the early to mid evening.

Forecast soundings by 00Z/Monday near and to the southwest of the
Dallas/Fort Worth Metroplex show moderate deep-layer shear and steep
low to mid-level lapse rates. The moderate deep-layer shear is
mostly due to mid-level speed shear, although some directional shear
is evident in the low levels. 700-500 mb lapse rates are forecast to
be near 8 C/km. This environment should support supercells
associated with isolated large hail. Large temperature-dewpoint
spreads will result in high storm bases, and a nearly adiabatic
lapse rate below 850 mb will contribute to downdraft acceleration.
As a result, a wind-damage threat is also expected to develop during
the late afternoon and early evening. The cold front is forecast to
be a bit faster than some of the model solutions are suggesting. For
this reason, the faster model solutions are favored and the slight
risk has been placed accordingly.

..Broyles.. 09/22/2023

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SPC Day 2 Fire Weather Outlook

SPC Day 2 Fire Weather Outlook

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook Image
Day 2 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
0130 AM CDT Fri Sep 22 2023

Valid 231200Z - 241200Z

...NO CRITICAL AREAS...

...Synopsis...
Fire weather concerns should remain fairly localized for Saturday
along the High Plains. A surface low and an attendant surface trough
are forecast to deepen as they migrate east across the Plains on
Saturday. This will establish a zonal flow regime across much of the
Rockies and High Plains by late morning. Downslope warming/drying
along the CO Front Range and in the lee of the Sangre de Cristo and
Sandia/Manzano Mountains, augmented by diurnal heating, should
promote areas of 15-25% RH as winds increase to 15-20 mph (with
locally drier/windier in terrain-favored locations). Somewhat meager
mid to upper-level winds should confine the strongest surface winds
close to terrain features - with the exception of southeast WY into
adjacent portions of NE/northeast CO where surface gradient winds
will be stronger. This, combined with somewhat marginal fuel status
outside of far northeast NM and southern CO, will limit the coverage
of elevated conditions and the overall fire weather threat.

..Moore.. 09/22/2023

...Please see www.spc.noaa.gov/fire for graphic product...

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SPC Sep 22, 2023 0600 UTC Day 2 Convective Outlook

SPC Sep 22, 2023 0600 UTC Day 2 Convective Outlook

SPC 0600Z Day 2 Outlook
Day 2 Outlook Image
Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
0100 AM CDT Fri Sep 22 2023

Valid 231200Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE GREAT PLAINS...AND LOWER TO MID MISSOURI VALLEY...

...SUMMARY...
Thunderstorms, associated with large hail and wind damage, will be
possible on Saturday across eastern parts of the Great Plains, and
in the Lower to Mid Missouri Valley. Marginally severe storms will
also be possible in parts of the Mid-Atlantic.

...Great Plains/Lower to Mid Missouri Valley...
An upper-level low will move northeastward across the northern
Plains on Saturday as an associated mid-level jet moves through the
base of the trough. At the surface, a low will move quickly
northward from eastern Nebraska into western Minnesota, as a cold
front moves eastward through the central Plains. As surface heating
takes place ahead of the front, scattered thunderstorms are expected
to develop from parts of the eastern Dakotas south-southeastward
into parts of the lower to mid Missouri Valley. Cell coverage will
gradually increase in the late afternoon and early evening, with MCS
development likely across parts of the region.

By midday, a north-to-south corridor of moderate instability will
likely be in place from eastern Kansas northward into eastern
Nebraska, where MLCAPE is forecast to peak in the 1500 to 2500 J/kg
range. Moderate to strong deep-layer shear will also be present
along this corridor, with the strongest shear located beneath the
mid-level jet in the mid Missouri Valley. The thermodynamic and
kinematic environment should support supercell development, with the
greatest supercell threat located from near the axis of the jet
southward. This is forecast to be in far eastern Nebraska and
western Iowa, where the combination of instability and shear is
forecast to be the greatest. Supercells will have a threat for large
hail and wind damage.

Further north into parts of eastern South Dakota and western
Minnesota, there is some uncertainty concerning how much instability
will develop. The more aggressive solutions with instability suggest
that supercells will be possible with a threat for large hail and
wind damage. Because of the uncertainty concerning instability, the
slight risk over far eastern South Dakota and southwest Minnesota is
more conditional.

...Southern Plains...
At mid-levels, west-southwesterly flow will be in place on Saturday
across much of the Desert Southwest and southern Rockies, with
northwesterly divergent flow located over much of the southern
Plains. At the surface, a cold front will advance southeastward into
the southern High Plains. Isolated to scattered thunderstorms are
expected to form along and near the front by afternoon, as moderate
to strong instability develops. Several storm clusters appear likely
to become organized in the late afternoon, persisting into the early
to mid evening.

Forecast soundings ahead of the front, from Oklahoma City to Wichita
Falls, suggest that MLCAPE will peak in the 2000 to 3000 J/kg range
during the late afternoon. 0-6 km shear is forecast to be in the 35
to 45 knot range, with 700-500 mb lapse rates near 7.5 C/km. This
environment will likely support supercells with large hail. Wind
damage may also occur, especially with mixed mode cell clusters that
become organized. The severe threat from far southern Oklahoma to
west-central Texas will likely be marginal, due to a lack of
large-scale ascent.

...Mid-Atlantic...
A tropical system is forecast by the National Hurricane Center to
move through eastern North Carolina on Saturday. To the east of the
center, instability is forecast to increase during the day from
eastern north Carolina into eastern Virginia. A marginal tornado
threat may develop with bands of convection that move through the
stronger instability.

..Broyles.. 09/22/2023

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SPC Day 1 Fire Weather Outlook

SPC Day 1 Fire Weather Outlook

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook Image
Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1249 AM CDT Fri Sep 22 2023

Valid 221200Z - 231200Z

...Synopsis...
Areas of elevated fire weather conditions are probable this
afternoon across a broad swath of the Four Corners region and into
the Front Range of southern CO and northeast NM, though fuel status
will be a limiting factor across much of this region. Early-morning
low-level water vapor imagery depicts a plume of drier low to
mid-level air from southern CA to northeast AZ on the southern
periphery of a upper low over the northern Great Basin. 00Z
soundings within this dry plume sampled average RH in the 850-700 mb
layer around 20-30%. This dry air mass is expected to spread north
across much of the Four Corners over the next 12-24 hours, and
should mix to the surface amid deep diurnal heating/mixing. The
combination of dry air advection, diurnal warming, and downslope
warming/drying in the lee of terrain features will support
widespread RH reductions into the low teens with 15-20 mph winds.
Recent ensemble guidance shows reasonably good consensus for this
scenario, but latest ERC analyses suggests that fuels across much of
the region are not currently receptive. Local fuel reports from
northeast NM into southeast CO suggest that fuels are regionally
drier and may support a fire weather concern. Consequently,
highlights are maintained across this region where the fire weather
threat is higher.

..Moore.. 09/22/2023

...Please see www.spc.noaa.gov/fire for graphic product...

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SPC Sep 22, 2023 0600 UTC Day 1 Convective Outlook

SPC Sep 22, 2023 0600 UTC Day 1 Convective Outlook

SPC 1200Z Day 1 Outlook
Day 1 Outlook Image
Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1246 AM CDT Fri Sep 22 2023

Valid 221200Z - 231200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE NORTHERN AND CENTRAL HIGH PLAINS...AND OVER THE SOUTHERN COASTAL
MIDDLE ATLANTIC...

...SUMMARY...
Severe thunderstorms are possible across parts of the central and
northern High Plains, mainly this afternoon and this evening. A few
tornadoes are also possible along the Mid-Atlantic Coast early
Saturday morning in association with the approaching potential
tropical system.

...Northern/Central High Plains...

Strong upper low that has settled into the northern Great Basin will
advance into western WY by late afternoon as a 70kt 500mb speed max
rotates through the base of the trough to near WY/UT/CO border by
23/00z. Seasonally cold mid-level temperatures (-20C at 500mb
beneath the upper low) will spread east in association with this
feature, and the exit region of aforementioned jet will overspread
the High Plains of eastern WY by early afternoon.

Latest model guidance suggests boundary-layer flow will remain
decidedly easterly across NE and the Dakotas into eastern WY. As a
result, strongest boundary-layer heating will be noted across the
higher plateau region of WY immediately ahead of the approaching
trough. Forecast soundings suggest convective temperatures will be
breached by 19z, and thunderstorms should develop shortly
thereafter. Soundings across eastern WY exhibit substantial SBCAPE
with steep lapse rates through 8km. NAM 21z forecast sounding for
LUS strongly favors supercells with 60kt surface-6km bulk shear.
Very large hail may accompany some of this activity as it spreads
toward the southern Black Hills region/northwestern NE.
Additionally, relatively moist boundary-layer conditions and low
LFCs suggest some tornado threat. It's not clear how far this
activity will spread east before weakening, as the updrafts will
likely decouple from the boundary layer due to much cooler surface
temperatures and weaker low-level lapse rates. For this reason have
focused higher severe probabilities across the High Plains where
stronger surface heating is expected.

...Potential Tropical Cyclone Sixteen...

PTC 16, currently located well southeast of the Carolina Coast, is
forecast to move north-northwest over the next 24hr, likely
intensifying as it approaches the NC Coast early Saturday. As this
system intensifies, low-level shear will increase markedly across
the southern Middle Atlantic Coast. Probabilities for supercells
will increase late, especially after 06Z, along with some risk for
tornadoes, primarily east of the low track.

Reference https://www.nhc.noaa.gov for more information on this
developing system.

..Darrow/Moore.. 09/22/2023

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Severe Thunderstorm Warning

Severe Thunderstorm Warning

This is an automatic message WUUS52 KGSP 150312
SVRGSP
NCC045-071-109-SCC021-091-150400-
/O.NEW.KGSP.SV.W.0024.190415T0312Z-190415T0400Z/

BULLETIN – IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Greenville-Spartanburg SC
1112 PM EDT Sun Apr 14 2019

The National Weather Service in Greenville-Spartanburg has issued a

* Severe Thunderstorm Warning for…
Eastern Lincoln County in the Piedmont of North Carolina…
Southeastern Cleveland County in the Piedmont of North Carolina…
Gaston County in the Piedmont of North Carolina…
Northwestern York County in Upstate South Carolina…
Northeastern Cherokee County in Upstate South Carolina…

* Until midnight EDT.

* At 1112 PM EDT, severe thunderstorms were located along a line
extending from near Shelby to 19 miles west of Gastonia to 6 miles
east of Gaffney, moving east at 35 mph.

HAZARD…60 mph wind gusts.

SOURCE…Radar indicated.

IMPACT…Expect damage to trees and power lines.

* Locations impacted include…
Gastonia, Shelby, Kings Mountain, Mt Holly, Belmont, Cherryville,
Bessemer City, South Gastonia, Clover and Dallas.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

Scattered trees and power lines will be blown down in the warned
area. Seek shelter inside an interior room.

These storms are also producing extremely heavy rainfall. Flooding of
drainage ditches and low lying areas may occur. Small streams will
rise rapidly. Do not drive through areas where water is flowing over
the road.

Please report damaging winds, hail, or flooding to the National
Weather Service Greenville-Spartanburg by calling toll free, 1, 800,
2 6 7, 8 1 0 1, or by posting on our Facebook page, or Tweet it using
hashtag nwsgsp. Your message should describe the event and the
specific location where it occurred.

&&

A Tornado Watch remains in effect until 500 AM EDT for the Piedmont
of North Carolina…and Upstate South Carolina.

LAT…LON 3535 8097 3530 8100 3527 8102 3517 8100
3515 8101 3514 8105 3510 8103 3509 8106
3495 8165 3515 8157 3530 8163 3555 8106
3555 8096 3550 8096 3549 8095 3545 8094
3543 8096 3539 8095 3537 8099 3536 8092
TIME…MOT…LOC 0312Z 248DEG 32KT 3526 8153 3518 8150 3504 8155

TORNADO…POSSIBLE
HAIL…<.75IN WIND...60MPH $$ HG

Severe Thunderstorm Warning

Severe Thunderstorm Warning

This is an automatic message WUUS52 KGSP 150215
SVRGSP
SCC045-059-083-150300-
/O.NEW.KGSP.SV.W.0022.190415T0215Z-190415T0300Z/

BULLETIN – IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Greenville-Spartanburg SC
1015 PM EDT Sun Apr 14 2019

The National Weather Service in Greenville-Spartanburg has issued a

* Severe Thunderstorm Warning for…
Northwestern Laurens County in Upstate South Carolina…
East central Greenville County in Upstate South Carolina…
Central Spartanburg County in Upstate South Carolina…

* Until 1100 PM EDT.

* At 1015 PM EDT, a severe thunderstorm was located 14 miles
southeast of Greenville Downtown, or 4 miles southeast of Five
Forks, moving east at 40 mph.

HAZARD…60 mph wind gusts.

SOURCE…Radar indicated.

IMPACT…Expect damage to trees and power lines.

* Locations impacted include…
Spartanburg, Simpsonville, Five Forks, Fountain Inn, Woodruff,
Pacolet, Cowpens, Roebuck, Pacolet Mills and Reidville.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

Scattered trees and power lines will be blown down in the warned
area. Seek shelter inside an interior room.

This storm is also producing extremely heavy rainfall. Flooding of
drainage ditches and low lying areas may occur. Small streams will
rise rapidly. Do not drive through areas where water is flowing over
the road.

Please report damaging winds, hail, or flooding to the National
Weather Service Greenville-Spartanburg by calling toll free, 1, 800,
2 6 7, 8 1 0 1, or by posting on our Facebook page, or Tweet it using
hashtag nwsgsp. Your message should describe the event and the
specific location where it occurred.

&&

A Tornado Watch remains in effect until 500 AM EDT for Upstate South
Carolina.

LAT…LON 3463 8224 3482 8228 3503 8180 3499 8177
3493 8176 3493 8174 3491 8172 3483 8179
3461 8185
TIME…MOT…LOC 0215Z 250DEG 35KT 3476 8216

TORNADO…POSSIBLE
HAIL…<.75IN WIND...60MPH $$ HG

Severe Thunderstorm Warning

Tornado Warning

This is an automatic message WFUS52 KGSP 150116
TORGSP
SCC007-150145-
/O.NEW.KGSP.TO.W.0010.190415T0116Z-190415T0145Z/

BULLETIN – EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Greenville-Spartanburg SC
916 PM EDT Sun Apr 14 2019

The National Weather Service in Greenville-Spartanburg has issued a

* Tornado Warning for…
Central Anderson County in Upstate South Carolina…

* Until 945 PM EDT.

* At 916 PM EDT, a severe thunderstorm capable of producing a tornado
was located 10 miles southwest of Anderson, or near Lake Hartwell,
moving northeast at 35 mph.

HAZARD…Tornado.

SOURCE…Radar indicated rotation.

IMPACT…Flying debris will be dangerous to those caught without
shelter. Mobile homes will be damaged or destroyed.
Damage to roofs, windows, and vehicles will occur. Tree
damage is likely.

* This dangerous storm will be near…
Anderson, Northlake, Anderson Airport and Homeland Park around 930
PM EDT.
Belton around 940 PM EDT.

Other locations impacted by this dangerous thunderstorm include Sandy
Springs, Sadlers Creek State Park and Broadway Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

Please report damaging winds, hail, or flooding to the National
Weather Service Greenville-Spartanburg by calling toll free, 1, 800,
2 6 7, 8 1 0 1, or by posting on our Facebook page, or Tweet it using
hashtag nwsgsp. Your message should describe the event and the
specific location where it occurred.

&&

LAT…LON 3437 8284 3444 8286 3447 8287 3449 8291
3448 8292 3449 8293 3475 8252 3467 8246
3462 8245 3459 8242 3456 8242 3454 8239
3451 8237 3435 8281
TIME…MOT…LOC 0116Z 238DEG 31KT 3446 8281

TORNADO…RADAR INDICATED
HAIL…<.75IN $$ HG

Severe Thunderstorm Warning

Tornado Warning

This is an automatic message WFUS52 KGSP 150041
TORGSP
NCC089-175-SCC045-077-150115-
/O.NEW.KGSP.TO.W.0009.190415T0041Z-190415T0115Z/

BULLETIN – EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Greenville-Spartanburg SC
841 PM EDT Sun Apr 14 2019

The National Weather Service in Greenville-Spartanburg has issued a

* Tornado Warning for…
Southeastern Transylvania County in western North Carolina…
South central Henderson County in western North Carolina…
Northwestern Greenville County in Upstate South Carolina…
Northwestern Pickens County in Upstate South Carolina…

* Until 915 PM EDT.

* At 841 PM EDT, a severe thunderstorm capable of producing a tornado
was located 11 miles northwest of Pickens, or 5 miles northeast of
Jocassee Gorges, moving northeast at 40 mph.

HAZARD…Tornado.

SOURCE…Radar indicated rotation.

IMPACT…Flying debris will be dangerous to those caught without
shelter. Mobile homes will be damaged or destroyed.
Damage to roofs, windows, and vehicles will occur. Tree
damage is likely.

* This dangerous storm will be near…
Table Rock State Park around 850 PM EDT.
Caesars Head State Park and Dupont State Forest around 900 PM EDT.
Jones Gap State Park and Pleasant Ridge State Park around 910 PM
EDT.

Other locations impacted by this dangerous thunderstorm include
Sunset, Pumpkintown, Little River In Transylvania County, Connestee
and Crab Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

Please report damaging winds, hail, or flooding to the National
Weather Service Greenville-Spartanburg by calling toll free, 1, 800,
2 6 7, 8 1 0 1, or by posting on our Facebook page, or Tweet it using
hashtag nwsgsp. Your message should describe the event and the
specific location where it occurred.

&&

LAT…LON 3532 8258 3509 8239 3489 8283 3501 8293
3501 8291 3502 8292 3503 8292 3505 8290
3504 8296
TIME…MOT…LOC 0041Z 237DEG 35KT 3502 8281

TORNADO…RADAR INDICATED
HAIL…<.75IN $$ HG