Hail, Osage
- When
- August 13, 12:59 AM CST
- Where
- Osage County, Burbank
- Measured
- 1.75 in hail
- Property damage
- $25,000
- Reported by
- Public
- Coordinates
- 36.700, -96.720
Golf ball size hail damaged vehicles and homes.
Flash Flood and Hail in Oklahoma, August 13, 2020
Thunderstorms developed across north central Oklahoma and south central Kansas during the early morning hours of the 13th, as a low level jet strengthened across the region. Moderately strong instability combined with strong deep layer wind shear to produce severe thunderstorms with large hail up to golf ball size and damaging wind gusts.
Where it happened
Every event with a place to put it. Tap one for its entry below.
- Tornadoes
- Tropical storms and surge
- Floods
- Wind
- Hail
- Winter weather
- Heat and drought
- Cold
- Fire, smoke and dust
- Marine and coastal
- Other
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- $52,000
- Crop damage
- None recorded
- Events
- 11
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
What happened
The episode as NWS TSA wrote it up.
Thunderstorms developed across north central Oklahoma and south central Kansas during the early morning hours of the 13th, as a low level jet strengthened across the region. Moderately strong instability combined with strong deep layer wind shear to produce severe thunderstorms with large hail up to golf ball size and damaging wind gusts. In addition, slow moving storms that moved repeatedly across the same area resulted in locally heavy rainfall and localized flash flooding.
What forecasters said that day
The local office's own words before the first event, 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 the first event at Aug 12, 11:19 PM CST, 1 hour 40 minutes earlier.
Area forecast discussion, Aug 12, 11:19 PM CST, 1 hour 40 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.....10Hazardous weather outlook, Aug 12, 3:27 PM CST, 9 hours 32 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 12, 11:24 PM CST, 1 hour 35 minutes before
Special Weather Statement
National Weather Service Tulsa OK
1224 AM CDT Thu Aug 13 2020
OKZ054-130615-
Osage OK-
1224 AM CDT Thu Aug 13 2020
...SIGNIFICANT WEATHER ADVISORY FOR WEST CENTRAL OSAGE COUNTY UNTIL
115 AM CDT...
At 1224 AM CDT, a strong thunderstorm was located 5 miles south of
Kaw City, moving east at 30 mph.
Penny size hail and wind gusts up to 50 mph will be possible with
this storm.
Locations in or near the path include...
Fairfax... Shidler...
Burbank... Southern Kaw Lake...
Apperson...
LAT...LON 3668 9694 3669 9693 3672 9692 3675 9689
3675 9687 3674 9683 3676 9682 3677 9682
3677 9679 3678 9679 3680 9644 3653 9645
3658 9690 3660 9692 3659 9695
TIME...MOT...LOC 0524Z 271DEG 28KT 3668 9685Special weather statement, Aug 12, 11:52 PM CST, 1 hour 7 minutes before
Special Weather Statement National Weather Service Tulsa OK 1252 AM CDT Thu Aug 13 2020 OKZ054-059-130645- Osage OK-Pawnee OK- 1252 AM CDT Thu Aug 13 2020 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL OSAGE AND CENTRAL PAWNEE COUNTIES UNTIL 145 AM CDT... At 1252 AM CDT, a strong thunderstorm was located near Ralston, moving east at 25 mph. Nickel size hail and wind gusts up to 50 mph will be possible with this storm. Locations in or near the path include... Ralston... Blackburn... 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 3643 9681 3655 9674 3644 9644 3629 9648 TIME...MOT...LOC 0552Z 287DEG 23KT 3650 9669
The radar
The Tulsa radar (KINX), 119 km away, was scanning. The volume nearest the first event began at 07:00 UTC.
Event by event
7 thunderstorm wind, 3 hail, 1 flash flood. Local standard time, as filed.
Hail, Osage
- When
- August 13, 1:40 AM CST
- Where
- Osage County, Hominy
- Measured
- 1.75 in hail
- Property damage
- $25,000
- Reported by
- Emergency Manager
- Coordinates
- 36.420, -96.400
Golf ball size hail damaged vehicles and homes.
Hail, Osage
- When
- August 13, 1:57 AM CST
- Where
- Osage County, 4 mi W of Skiatook
- Measured
- 1 in hail
- Reported by
- Broadcast Media
- Coordinates
- 36.370, -96.072
Thunderstorm Wind, Osage
- When
- August 13, 1:57 AM CST
- Where
- Osage County, 4 mi W of Skiatook
- Measured
- 52 kt (60 mph) estimated gust
- Reported by
- Broadcast Media
- Coordinates
- 36.370, -96.072
Thunderstorm wind gusts were estimated to 60 mph.
Thunderstorm Wind, Tulsa
- When
- August 13, 2:24 AM CST
- Where
- Tulsa County, 2.84 mi NW of Dawson
- Measured
- 55 kt (63 mph) measured gust
- Reported by
- Mesonet
- Coordinates
- 36.197, -95.939
The Oklahoma Mesonet station near Tulsa measured 63 mph thunderstorm wind gusts.
Thunderstorm Wind, Tulsa
- When
- August 13, 2:30 AM CST
- Where
- Tulsa County, 1.72 mi SSE of Dawson
- Measured
- 65 kt (75 mph) estimated gust
- Reported by
- NWS Employee
- Coordinates
- 36.148, -95.886
Strong thunderstorm wind blew down trees, and snapped large tree limbs.
Thunderstorm Wind, Tulsa
- When
- August 13, 2:37 AM CST
- Where
- Tulsa County, 1.59 mi S of Dawson
- Measured
- 56 kt (64 mph) estimated gust
- Reported by
- NWS Employee
- Coordinates
- 36.147, -95.904
Strong thunderstorm wind snapped large tree limbs.
Thunderstorm Wind, Tulsa
- When
- August 13, 2:54 AM CST
- Where
- Tulsa County, 1.19 mi NE of Bixby
- Measured
- 53 kt (61 mph) measured gust
- Reported by
- Mesonet
- Coordinates
- 35.963, -95.866
The Oklahoma Mesonet station near Bixby measured 61 mph thunderstorm wind gusts.
Thunderstorm Wind, Tulsa
- When
- August 13, 2:55 AM CST
- Where
- Tulsa County, 1 mi N of Bixby
- Measured
- 65 kt (75 mph) estimated gust
- Reported by
- Broadcast Media
- Coordinates
- 35.965, -95.880
Strong thunderstorm wind blew down trees.
Flash Flood, Tulsa
- When
- August 13, 3:12 AM CST to 7:00 AM CST
- Where
- Tulsa County, 2.55 mi SE of Dawson to 1.72 mi ESE of Dawson
- Cause
- Heavy Rain
- Reported by
- NWS Employee
- Coordinates
- 36.142, -95.870
Portions of E 11th Street were flooded west of Highway 169 and east of S Yale Avenue.
Thunderstorm Wind, Muskogee
- When
- August 13, 4:30 AM CST
- Where
- Muskogee County, Warner
- Measured
- 65 kt (75 mph) estimated gust
- Property damage
- $2,000
- Reported by
- Emergency Manager
- Coordinates
- 35.500, -95.300
Strong thunderstorm wind blew down trees, and snapped a power pole.
What these are
- Hail
- Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
- Thunderstorm Wind
- Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
- Flash Flood
- Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Excessive Heat and Heat in Arizona, August 13 to 19, 2020
- Tornadoes and Flash Flooding in Minnesota, August 13 to 14, 2020
- Excessive Heat in California, August 13 to 20, 2020
- Hail and Damaging Winds in North Dakota, August 13 to 14, 2020
- Wildfire in Texas, August 13 to 16, 2020
- Wildfire in California, August 13 to 28, 2020
- Damaging Winds and Lightning Strikes in Georgia, August 13 to 14, 2020
- Flash Flood in Indiana, August 13, 2020
- Tornadoes and Hail in Minnesota, August 13, 2020
- Flash Flooding and Flooding in Virginia, August 13, 2020
- Heat in Texas, August 13, 2020
- Heat in Louisiana, August 13, 2020
More
Every storm in Oklahoma in 2020Every state in 2020This day in weather historyWarnings in Oklahoma, August 2020
Sources
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 907842, 914790, 914792, 914793, 914794, 914795, 914796, 914797, 914791, 914798, 914799.