Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 54, NWS Tulsa, OK
NWS Tulsa, OK issued this severe thunderstorm warning at Apr 20, 2020, 4:32 PM CDT for Delaware County, Ottawa County, Oklahoma. It was in force for 58 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Apr 20, 2020, 4:32 PM CDT (21:32 UTC)
- Expired
- Apr 20, 2020, 5:30 PM CDT
- In force
- 58 min
- Issued by
- NWS Tulsa, OK
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Delaware County, OK, Ottawa County, OK
The radar
The Tulsa radar (KINX), 84 km from the middle of the area, began a volume at 21:35 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.
The nearest sounding before it
Springfield, MO (KSGF), launched 12:00Z, 9.5 hours before the alert went out and 95 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1600 m above ground
- 0-6 km bulk shear
- 54 kt
- 0-1 km storm-relative helicity
- 58 m²/s²
- 0-3 km storm-relative helicity
- 79 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 Apr 20, 1:44 PM CDT, 2 hours 48 minutes earlier.
Area forecast discussion, Apr 20, 1:44 PM CDT, 2 hours 48 minutes before
Area Forecast Discussion National Weather Service Tulsa OK 144 PM CDT Mon Apr 20 2020 .DISCUSSION... Scattered thunderstorm are expected to develop later this afternoon across northeast Oklahoma and northwest Arkansas as a weak surface trof moves into the region. The cap has pretty well eroded across this region with surface based cape expected to be between 1500 to 2000 j/kg late this afternoon. Some of these storms could become strong to severe with hail to the size of quarters and wind gusts to around 60 mph possible. This activity is expected to diminish this evening as is moves into a more stable environment and the surface boundary weakens considerably. The next chance of showers and thunderstorms will come Tuesday night through Wednesday night. Strong isentropic lift is forecast to develop across eastern Oklahoma and western Arkansas Tuesday night as the low level jet strengthens in advance of a mid-level low moving out of the Southern Rockies into the Plains. The mid-level low will move across Oklahoma Wednesday into Wednesday night before exiting to the east Thursday morning. The associated surface low is set track across southern Oklahoma during this time. The best chances for surface based thunderstorms will be Wednesday afternoon and evening across southeast Oklahoma and west-central Arkansas. This is where the greatest potential for severe thunderstorms will exist with large hail and gusty winds the main concern. However, the elevated storms across northeast Oklahoma and northwest Arkansas will also have the potential to be severe with large hail the main concern. Heavy rain will also be a concern during this time with most of the area seeing 1 to 2 inches of rain with locally higher amounts possible. After a brief respite, the chances of showers and thunderstorms return Thursday night into Friday as a cold front sweeps through the region. && .PRELIMINARY POINT TEMPS/POPS... TUL 49 76 56 68 / 30 0 80 90 FSM 50 78 55 69 / 20 0 80 90 MLC 52 78 58 69 / 10 10 80 90 BVO 48 75 53 66 / 10 0 80 90 FYV 49 75 53 65 / 40 0 60 90 BYV 47 72 51 64 / 40 0 60 90 MKO 49 76 55 67 / 30 0 80 90 MIO 46 72 53 64 / 10 0 60 90 F10 51 77 56 69 / 30 0 90 90 HHW 52 77 58 70 / 10 10 50 90 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...None. AR...None. && LONG TERM....10
Hazardous weather outlook, Apr 20, 1:20 PM CDT, 3 hours 12 minutes before
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</html>In the hours before
Special weather statement, Apr 20, 3:41 PM CDT, 51 minutes before
Special Weather Statement National Weather Service Tulsa OK 341 PM CDT Mon Apr 20 2020 OKZ057-058-202130- Craig OK-Ottawa OK- 341 PM CDT Mon Apr 20 2020 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN CRAIG AND CENTRAL OTTAWA COUNTIES UNTIL 430 PM CDT... At 341 PM CDT, a strong thunderstorm was located 3 miles northeast of Welch, moving east at 40 mph. Penny size hail and wind gusts up to 50 mph will be possible with this storm. Locations in or near the path include... Miami... Commerce... Welch... Wyandotte... Narcissa... Ottawa... Peoria... Twin Bridges State Park... This includes Interstate 44 between mile markers 302 and 319. LAT...LON 3694 9462 3668 9462 3686 9511 3696 9507 TIME...MOT...LOC 2041Z 284DEG 33KT 3690 9503
Special weather statement, Apr 20, 3:54 PM CDT, 38 minutes before
Special Weather Statement National Weather Service Tulsa OK 354 PM CDT Mon Apr 20 2020 OKZ057-202130- Craig OK- 354 PM CDT Mon Apr 20 2020 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN CRAIG COUNTY UNTIL 430 PM CDT... At 354 PM CDT, a strong thunderstorm was located 11 miles west of Welch, 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... Welch... Bluejacket... Hollow... Pyramid Corners... LAT...LON 3685 9537 3693 9536 3695 9500 3672 9500 TIME...MOT...LOC 2054Z 280DEG 26KT 3687 9530
Special weather statement, Apr 20, 4:15 PM CDT, 17 minutes before
Special Weather Statement National Weather Service Tulsa OK 415 PM CDT Mon Apr 20 2020 OKZ054-202145- Osage OK- 415 PM CDT Mon Apr 20 2020 ...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL OSAGE COUNTY UNTIL 445 PM CDT... At 415 PM CDT, a strong thunderstorm was located near Wynona, 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... Skiatook... Barnsdall... Wynona... Avant... Wolco... LAT...LON 3655 9600 3632 9600 3647 9642 3657 9639 TIME...MOT...LOC 2115Z 282DEG 28KT 3650 9632
The office that day
Everything else NWS Tulsa, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 19, 10:31 PM CDT | Dense Fog Advisory | TSA | Haskell, Latimer, McIntosh, Muskogee, Pittsburg | 12 hr |
| Apr 20, 3:41 PM CDT | Special Weather Statement | TSA | Ottawa | 49 min |
| Apr 20, 3:54 PM CDT | Special Weather Statement | TSA | Craig | 36 min |
| Apr 20, 4:15 PM CDT | Special Weather Statement | TSA | Osage | 30 min |
| Apr 20, 4:46 PM CDT | Special Weather Statement | TSA | Craig | 29 min |
| Apr 20, 5:38 PM CDT | Special Weather Statement | TSA | Wagoner | 37 min |
| Apr 20, 6:15 PM CDT | Special Weather Statement | TSA | Wagoner | 45 min |
| Apr 20, 5:30 PM CDT | Special Weather Statement | TSA | Benton | 45 min |
| Apr 20, 5:34 PM CDT | Severe Thunderstorm Warning | TSA | Benton | 56 min |
| Apr 20, 6:25 PM CDT | Severe Thunderstorm Warning | TSA | Benton, Madison, Washington | 50 min |
Nearby
Severe Thunderstorm Warnings in Oklahoma, 2020Every 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.