Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 327, NWS Tulsa, OK

August 13, 2020Creek County, Pawnee County, Tulsa County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at Aug 13, 2020, 3:36 AM CDT for Creek County, Pawnee County, Tulsa County, Oklahoma. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 13, 2020, 3:36 AM CDT (08:36 UTC)
Expired: Aug 13, 2020, 4:15 AM CDT
In force: 39 min
Issued by: NWS Tulsa, OK
Area: Storm-based polygon
Hail: 2.0 in
Wind: 70.0 mph

Counties Creek County, OK, Pawnee County, OK, Tulsa County, OK

The radar

The Tulsa radar (KINX), 69 km from the middle of the area, began a volume at 08:40 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 8.6 hours before the alert went out and 144 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 3207 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 1596 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 39 m²/s²
0-3 km storm-relative helicity: 214 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 14.3

Open this sounding in Storm Lab

The text

As transmitted.

233 
WUUS54 KTSA 130836
SVRTSA
OKC037-117-143-130915-
/O.NEW.KTSA.SV.W.0327.200813T0836Z-200813T0915Z/

BULLETIN - EAS ACTIVATION REQUESTED
Severe Thunderstorm Warning
National Weather Service Tulsa OK
336 AM CDT Thu Aug 13 2020

The National Weather Service in Tulsa has issued a

* Severe Thunderstorm Warning for...
  Northern Creek County in northeastern Oklahoma...
  Southeastern Pawnee County in northeastern Oklahoma...
  West central Tulsa County in northeastern Oklahoma...

* Until 415 AM CDT.

* At 336 AM CDT, a severe thunderstorm was located 3 miles northeast
  of Terlton, moving southeast at 25 mph.

  HAZARD...Two inch hail and 70 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           considerable tree damage. Wind damage is also likely to 
           mobile homes, roofs, and outbuildings.

* Locations in or near the path include...
  Sand Springs...                   Sapulpa...
  Cleveland...                      Mannford...
  Kellyville...                     Jennings...
  Westport...                       Hallett...
  Terlton...                        Keystone State Park...
  Silver City...                    

This includes Interstate 44 between mile markers 189 and 214.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move immediately to shelter inside a strong building. Stay
away from windows.

&&

LAT...LON 3633 9645 3629 9643 3626 9638 3623 9634
      3623 9627 3620 9624 3617 9627 3616 9627
      3616 9619 3601 9602 3582 9644 3626 9661
TIME...MOT...LOC 0836Z 322DEG 21KT 3624 9646 

HAIL...2.00IN
WIND...70MPH
 
$$

2 follow-up statements

682 
WWUS54 KTSA 130855
SVSTSA

Severe Weather Statement
National Weather Service Tulsa OK
355 AM CDT Thu Aug 13 2020

OKC037-117-143-130915-
/O.CON.KTSA.SV.W.0327.000000T0000Z-200813T0915Z/
Creek OK-Pawnee OK-Tulsa OK-
355 AM CDT Thu Aug 13 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 AM CDT
FOR NORTHERN CREEK...SOUTHEASTERN PAWNEE AND WEST CENTRAL TULSA
COUNTIES...

At 355 AM CDT, a severe thunderstorm was located near Mannford,
moving southeast at 30 mph.

HAZARD...Two inch hail and 70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect 
         considerable tree damage. Wind damage is also likely to 
         mobile homes, roofs, and outbuildings.

Locations in or near the path include...
Sand Springs...                   Sapulpa...
Mannford...                       Kellyville...
Westport...                       Keystone State Park...
Silver City...                    

This includes Interstate 44 between mile markers 189 and 214.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.

&&

LAT...LON 3615 9648 3618 9641 3620 9635 3623 9631
      3623 9627 3620 9624 3617 9627 3616 9627
      3616 9619 3601 9602 3582 9644 3607 9653
TIME...MOT...LOC 0855Z 319DEG 27KT 3611 9632 

HAIL...2.00IN
WIND...70MPH
 
$$

301 
WWUS54 KTSA 130911
SVSTSA

Severe Weather Statement
National Weather Service Tulsa OK
411 AM CDT Thu Aug 13 2020

OKC037-117-143-130921-
/O.EXP.KTSA.SV.W.0327.000000T0000Z-200813T0915Z/
Creek OK-Pawnee OK-Tulsa OK-
411 AM CDT Thu Aug 13 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN CREEK...SOUTHEASTERN
PAWNEE AND WEST CENTRAL TULSA COUNTIES WILL EXPIRE AT 415 AM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning will be allowed to expire.  However small hail,
gusty winds and heavy rain are still possible with this thunderstorm.

LAT...LON 3615 9648 3618 9641 3620 9635 3623 9631
      3623 9627 3620 9624 3617 9627 3616 9627
      3616 9619 3601 9602 3582 9644 3607 9653
TIME...MOT...LOC 0911Z 322DEG 21KT 3604 9626 

$$

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tulsa, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 13, 12:19 AM CDT, 3 hours 17 minutes earlier.

Area forecast discussion, Aug 13, 12:19 AM CDT, 3 hours 17 minutes before

Area Forecast Discussion
National Weather Service Tulsa OK
1219 AM CDT Thu Aug 13 2020

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
Scattered thunderstorms have the potential to impact all area
sites tonight and into Thursday morning. VFR conditions are
forecast at most sites outside of the thunderstorm areas.
However, MVFR conditions may be possible overnight at the
northwest Arkansas sites.

&&

.PREV DISCUSSION... /Issued 920 PM CDT Wed Aug 12 2020/

DISCUSSION...
Latest data continues to indicate convection develops across sern
KS and nern OK after midnight in low level warm advection regime.
As S/SWly low level jet strengthens across central/ern OK below
west-northwest flow aloft, activity should become organized
enough to spread across much of nern OK and nwrn AR through
Thursday morning, especially areas north of I-40. Trends in
ongoing forecast look good, but this update will reflect
increasing convective coverage through Thursday morning along with
higher QPF. Severe weather threat continues to look low, but is
nonzero.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   90  74  94  73 /  40  10  10  10
FSM   91  72  93  73 /  50  40  30  10
MLC   94  75  95  73 /  20   0  10  10
BVO   89  72  91  71 /  40  20  10  10
FYV   89  69  89  70 /  60  50  30  10
BYV   90  69  92  69 /  20  30  30  10
MKO   89  73  92  72 /  60  20  10  10
MIO   91  72  91  71 /  60  40  20  10
F10   91  74  94  72 /  30  10   0  10
HHW   97  75  97  75 /  10  10   0  10

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Heat Advisory from 1 PM this afternoon to 8 PM CDT this evening
     for OKZ049-053-064>066-071-073-075.

AR...None.
&&

AVIATION.....10

Hazardous weather outlook, Aug 12, 4:27 PM CDT, 11 hours 9 minutes before

Hazardous Weather Outlook
National Weather Service Tulsa OK
427 PM CDT Wed Aug 12 2020

ARZ001-002-010-011-019-020-029-OKZ049-053>076-131030-
Adair OK-Benton AR-Carroll AR-Cherokee OK-Choctaw OK-Craig OK-
Crawford AR-Creek OK-Delaware OK-Franklin AR-Haskell OK-Latimer OK-
Le Flore OK-Madison AR-Mayes OK-McIntosh OK-Muskogee OK-Nowata OK-
Okfuskee OK-Okmulgee OK-Osage OK-Ottawa OK-Pawnee OK-Pittsburg OK-
Pushmataha OK-Rogers OK-Sebastian AR-Sequoyah OK-Tulsa OK-Wagoner OK-
Washington OK-Washington AR-
427 PM CDT Wed Aug 12 2020

This Outlook is for Northwest and West Central Arkansas as well as
much of Eastern Oklahoma.

.DAY ONE...Tonight.

SEVERE THUNDERSTORM.
	RISK...Limited.
	AREA...Northeastern Oklahoma.
	ONSET...After 2 am.

DISCUSSION...
Thunderstorms are expected to develop into the area late tonight from
the northwest. These storms will pose a limited risk of severe
weather, generally north of I-40. Locally heavy rainfall is also
possible.

SPOTTER AND EMERGENCY MANAGEMENT ACTION STATEMENT...
Local Spotter Activation May Be Needed.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.
THURSDAY...Thunderstorm Potential...Dangerous Heat Potential.
FRIDAY...Thunderstorm Potential...Dangerous Heat Potential.
SATURDAY...Dangerous Heat Potential.
SUNDAY...Thunderstorm Potential...Dangerous Heat Potential.
MONDAY and TUESDAY...Thunderstorm Potential.

EXTENDED DISCUSSION...
Scattered thunderstorms will likely be ongoing across portions of
northeast Oklahoma, spreading into northwest Arkansas Thursday
morning before weakening. Additional scattered thunderstorms are
expected to develop across portions of northeast Oklahoma and
northwest Arkansas Thursday night into Friday morning. A few of these
storms could be severe with marginally severe hail and strong gusty
winds. In addition, a very moist air mass will remain in place, and
with the slow storm motions expected, locally heavy rainfall will
again be possible.

Afternoon heat index values around 105 degrees will be possible
through the weekend, and additional Heat Advisories may be needed
for portions of eastern Oklahoma and northwest Arkansas. A cold front
is forecast to arrive late in the weekend, with notably cooler and
drier weather possible by early next week.

weather.gov/tulsa contains additional information.

69

In the hours before

Special weather statement, Aug 13, 2:58 AM CDT, 38 minutes before

Special Weather Statement
National Weather Service Tulsa OK
258 AM CDT Thu Aug 13 2020

OKZ054-130845-
Osage OK-
258 AM CDT Thu Aug 13 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTH CENTRAL OSAGE COUNTY UNTIL
345 AM CDT...

At 258 AM CDT, a strong thunderstorm was located near Grainola,
moving southeast at 20 mph.

Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.

Locations in or near the path include...
Shidler...                        Grainola...
Foraker...                        Pearsonia...
Webb City...

LAT...LON 3680 9633 3663 9659 3686 9675 3692 9675
      3700 9663 3700 9659
TIME...MOT...LOC 0758Z 321DEG 16KT 3690 9664

Local storm report, Aug 13, 3:01 AM CDT, 35 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
301 AM CDT THU AUG 13 2020

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

0240 AM     HAIL             HOMINY                  36.41N 96.39W
08/13/2020  M1.75 INCH       OSAGE              OK   EMERGENCY MNGR

&&

JBM

Local storm report, Aug 13, 3:03 AM CDT, 33 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
303 AM CDT THU AUG 13 2020

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

0257 AM     HAIL             4 W SKIATOOK            36.37N 96.07W
08/13/2020  E1.00 INCH       OSAGE              OK   BROADCAST MEDIA

            ALSO 60 MPH WINDS REPORTED.

&&

JBM

Special weather statement, Aug 13, 3:06 AM CDT, 30 minutes before

Special Weather Statement
National Weather Service Tulsa OK
306 AM CDT Thu Aug 13 2020

OKZ060-064-130845-
Tulsa OK-Creek OK-
306 AM CDT Thu Aug 13 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN CREEK AND WEST
CENTRAL TULSA COUNTIES UNTIL 345 AM CDT...

At 306 AM CDT, a strong thunderstorm was located 4 miles south of
Mannford, moving east at 20 mph.

Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.

Locations in or near the path include...
Tulsa...                          Sand Springs...
Sapulpa...                        Mannford...
Kellyville...                     Keystone State Park...

This includes Interstate 44 between mile markers 200 and 219.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3616 9640 3616 9629 3611 9600 3586 9612
      3586 9613 3601 9647
TIME...MOT...LOC 0806Z 290DEG 18KT 3607 9635

Local storm report, Aug 13, 3:33 AM CDT, 3 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
333 AM CDT THU AUG 13 2020

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

0324 AM     TSTM WND GST     4 NE TULSA              36.17N 95.87W
08/13/2020  M63 MPH          TULSA              OK   MESONET

&&

JBM

Local storm report, Aug 13, 3:36 AM CDT, 0 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
336 AM CDT THU AUG 13 2020

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

0330 AM     TSTM WND GST     TULSA                   36.13N 95.92W
08/13/2020  E60 MPH          TULSA              OK   NWS EMPLOYEE

&&

JBM

The office that day

Everything else NWS Tulsa, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 13, 12:24 AM CDT	Special Weather Statement	TSA	Osage	51 min
Aug 13, 12:50 AM CDT	Severe Thunderstorm Warning	TSA	Osage	40 min
Aug 13, 12:52 AM CDT	Special Weather Statement	TSA	Pawnee	53 min
Aug 13, 12:58 AM CDT	Severe Thunderstorm Warning	TSA	Osage, Pawnee	25 min
Aug 13, 1:21 AM CDT	Severe Thunderstorm Warning	TSA	Osage	54 min
Aug 13, 1:26 AM CDT	Severe Thunderstorm Warning	TSA	Osage	34 min
Aug 13, 1:59 AM CDT	Severe Thunderstorm Warning	TSA	Osage, Pawnee	61 min
Aug 13, 2:15 AM CDT	Severe Thunderstorm Warning	TSA	Osage	60 min
Aug 13, 2:20 AM CDT	Special Weather Statement	TSA	Osage	25 min
Aug 13, 2:27 AM CDT	Special Weather Statement	TSA	Tulsa	48 min
Aug 13, 2:40 AM CDT	Severe Thunderstorm Warning	TSA	Rogers, Tulsa	50 min
Aug 13, 2:53 AM CDT	Severe Thunderstorm Warning	TSA	Osage, Pawnee	52 min
Aug 13, 2:58 AM CDT	Special Weather Statement	TSA	Osage	47 min
Aug 13, 3:04 AM CDT	Severe Thunderstorm Warning	TSA	Osage	41 min
Aug 13, 3:06 AM CDT	Special Weather Statement	TSA	Creek	39 min
Aug 13, 3:07 AM CDT	Areal Flood Advisory	TSA	Osage, Pawnee, Tulsa	3 hr
Aug 13, 3:23 AM CDT	Severe Thunderstorm Warning	TSA	Creek, Okmulgee, Tulsa	52 min
Aug 13, 3:26 AM CDT	Severe Thunderstorm Warning	TSA	Tulsa, Wagoner	49 min
Aug 13, 3:39 AM CDT	Flash Flood Warning	TSA	Tulsa	5 hr
Aug 13, 3:44 AM CDT	Severe Thunderstorm Warning	TSA	Osage	34 min
Aug 13, 3:54 AM CDT	Severe Thunderstorm Warning	TSA	Creek, Muskogee, Okmulgee, Tulsa, Wagoner	51 min
Aug 13, 3:57 AM CDT	Areal Flood Advisory	TSA	Okmulgee, Tulsa, Wagoner	3 hr
Aug 13, 4:20 AM CDT	Special Weather Statement	TSA	Osage	40 min
Aug 13, 4:21 AM CDT	Special Weather Statement	TSA	Tulsa	39 min
Aug 13, 4:23 AM CDT	Severe Thunderstorm Warning	TSA	Cherokee, McIntosh, Muskogee, Okmulgee, Wagoner	52 min
Aug 13, 4:33 AM CDT	Severe Thunderstorm Warning	TSA	Creek, Okmulgee, Tulsa, Wagoner	42 min
Aug 13, 4:40 AM CDT	Special Weather Statement	TSA	Tulsa	35 min
Aug 13, 5:07 AM CDT	Special Weather Statement	TSA	Cherokee, Haskell, Sequoyah	53 min
Aug 13, 5:27 AM CDT	Severe Thunderstorm Warning	TSA	Haskell, Muskogee, Sequoyah	48 min
Aug 13, 5:29 AM CDT	Special Weather Statement	TSA	Tulsa	31 min
Aug 13, 6:01 AM CDT	Special Weather Statement	TSA	Sequoyah	44 min
Aug 13, 6:55 AM CDT	Areal Flood Advisory	TSA	Creek, Muskogee, Okmulgee, Tulsa, Wagoner	2 hr
Aug 13, 7:06 AM CDT	Special Weather Statement	TSA	Latimer	24 min
Aug 13, 7:32 AM CDT	Special Weather Statement	TSA	Latimer	28 min
Aug 13, 7:44 AM CDT	Areal Flood Advisory	TSA	Haskell, Latimer, LeFlore, McIntosh, Muskogee, Okmulgee and 1 more	3 hr
Aug 13, 8:16 AM CDT	Special Weather Statement	TSA	Latimer	44 min
Aug 13, 9:01 AM CDT	Special Weather Statement	TSA	LeFlore	44 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2020 Every severe thunderstorm warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.