Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 324, NWS Tulsa, OK

August 13, 2020Osage County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at Aug 13, 2020, 3:04 AM CDT for Osage County, Oklahoma. It was in force for 41 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, 3:04 AM CDT (08:04 UTC)
Expired: Aug 13, 2020, 3:45 AM CDT
In force: 41 min
Issued by: NWS Tulsa, OK
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

County Osage County, OK

The radar

The Tulsa radar (KINX), 114 km from the middle of the area, began a volume at 08:03 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, 8.1 hours before the alert went out and 192 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.

476 
WUUS54 KTSA 130804
SVRTSA
OKC113-130845-
/O.NEW.KTSA.SV.W.0324.200813T0804Z-200813T0845Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tulsa OK
304 AM CDT Thu Aug 13 2020

The National Weather Service in Tulsa has issued a

* Severe Thunderstorm Warning for...
  North central Osage County in northeastern Oklahoma...

* Until 345 AM CDT.

* At 304 AM CDT, a severe thunderstorm was located 3 miles south of
  Grainola, moving southeast at 20 mph.

  HAZARD...60 mph wind gusts and half dollar size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3674 9628 3657 9654 3685 9676 3686 9675
      3690 9675 3700 9661
TIME...MOT...LOC 0804Z 321DEG 16KT 3689 9664 

HAIL...1.25IN
WIND...60MPH
 
$$

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, 2 hours 45 minutes earlier.

Area forecast discussion, Aug 13, 12:19 AM CDT, 2 hours 45 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, 10 hours 37 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

Local storm report, Aug 13, 2:01 AM CDT, 1 hour 3 minutes before

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

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

0159 AM     HAIL             BURBANK                 36.69N 96.73W
08/13/2020  E1.75 INCH       OSAGE              OK   PUBLIC

&&

JBM

Special weather statement, Aug 13, 2:20 AM CDT, 44 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Tulsa OK
Issued by National Weather Service Norman OK
220 AM CDT Thu Aug 13 2020

OKZ054-130745-
Osage OK-
220 AM CDT Thu Aug 13 2020

...SIGNIFICANT WEATHER ADVISORY FOR north central Osage County Until
245 AM CDT....

AT 215 AM CDT...A STRONG THUNDERSTORM WAS LOCATED NEAR Shidler...
MOVING southeast AT 25 MPH.

HAZARDS INCLUDE...
HAIL UP TO THE SIZE OF NICKELS...
POTENTIALLY SEVERE WINDS GUSTING OVER 55 MPH...
MINOR FLOODING IN AREAS OF POOR DRAINAGE...

LOCATIONS IMPACTED INCLUDE...
Shidler and Webb City.

MONITOR THE WEATHER SITUATION CLOSELY AND BE ALERT FOR THREATENING
WEATHER CONDITIONS.

LAT...LON 3692 9675 3684 9648 3667 9666 3678 9678
      3678 9675
TIME...MOT...LOC 0715Z 305DEG 20KT 3682 9672

Special weather statement, Aug 13, 2:27 AM CDT, 37 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Tulsa OK
Issued by National Weather Service Norman OK
227 AM CDT Thu Aug 13 2020

OKZ054-060-061-130815-
Tulsa OK-Osage OK-Rogers OK-
227 AM CDT Thu Aug 13 2020

...SIGNIFICANT WEATHER ADVISORY FOR northeastern Tulsa...southeastern
Osage and west central Rogers Counties Until 315 AM CDT....

AT 223 AM CDT...A STRONG THUNDERSTORM WAS LOCATED NEAR Sperry...
MOVING southeast AT 25 MPH.

HAZARDS INCLUDE...
HAIL UP TO THE SIZE OF NICKELS...
POTENTIALLY SEVERE WINDS GUSTING OVER 55 MPH...
MINOR FLOODING IN AREAS OF POOR DRAINAGE...
FREQUENT CLOUD TO GROUND LIGHTNING...

LAT...LON 3632 9621 3644 9609 3627 9565 3608 9588
TIME...MOT...LOC 0723Z 304DEG 20KT 3629 9602

Special weather statement, Aug 13, 2:58 AM CDT, 6 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, 3 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, 1 minute 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

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, 3:06 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, 3:36 AM CDT	Severe Thunderstorm Warning	TSA	Creek, Pawnee, Tulsa	39 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.