Alert archive / Oklahoma / Mesoscale Discussions in 2021
Mesoscale Discussion 1562
The Storm Prediction Center issued this mesoscale discussion at Aug 19, 2021, 5:46 PM CDT for 10 counties in Oklahoma; 4 counties in Texas. It was in force for 59 min.
The area
The outline as issued.
The facts
- Issued
- Aug 19, 2021, 5:46 PM CDT (22:46 UTC)
- Expired
- Aug 19, 2021, 6:45 PM CDT
- In force
- 59 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 5%
Counties Beckham County, OK, Caddo County, OK, Comanche County, OK, Cotton County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Kiowa County, OK, Tillman County, OK, Washita County, OK, Clay County, TX, Hardeman County, TX, Wichita County, TX, Wilbarger County, TX
The radar
The Altus AFB radar (KFDR), 26 km from the middle of the area, began a volume at 22:49 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
Amarillo Airport, TX (KAMA), launched 12:00Z, 10.8 hours before the alert went out and 241 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
- 1123 J/kg
- Mixed-layer CIN
- -57 J/kg
- Mixed-layer LCL
- 988 m above ground
- 0-6 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- 33 m²/s²
- 0-3 km storm-relative helicity
- 89 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
305 ACUS11 KWNS 192247 SWOMCD SPC MCD 192246 OKZ000-TXZ000-192345- Mesoscale Discussion 1562 NWS Storm Prediction Center Norman OK 0546 PM CDT Thu Aug 19 2021 Areas affected...Southwest Oklahoma and Northwest Texas Concerning...Severe potential...Watch unlikely Valid 192246Z - 192345Z Probability of Watch Issuance...5 percent SUMMARY...Isolated damaging wind threat may continue for a few more hours, watch issuance not anticipated. DISCUSSION...Regional radar shows a small cluster of storms entering portions of southwest Oklahoma, with a history of producing damaging wind gusts, including a 71 kt gust at the Hollis, OK, mesonet site at 2210 UTC. These storms have formed in environment characterized by MLCAPE near 3500-4000 J/kg and weak deep-layer shear. Relatively steep low-level lapse rates near 8 C/km and modest low-level shear (25 kt 0-3 km AGL per KFDR VAD) is likely enough to support a continued threat of damaging wind gusts for a few more hours, at least until day time heating subsides. Given the current expectation for an isolated wind threat, watch issuance is unlikely. ..Karstens/Thompson.. 08/19/2021 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN...LUB...AMA... LAT...LON 33869954 34430018 35479969 35499816 33779819 33869954
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 19, 3:29 PM CDT | Mesoscale Discussion | SPC | Beaver, Texas | 2 hr |
Nearby
Mesoscale Discussions in Oklahoma, 2021Mesoscale Discussions in Texas, 2021Every mesoscale discussion in 2021
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.