Alert archive / Texas / Mesoscale Discussions in 2021
Mesoscale Discussion 1937
The Storm Prediction Center issued this mesoscale discussion at Nov 10, 2021, 5:06 PM CST for 7 counties in Oklahoma; 29 counties in Texas. It was in force for 114 min.
The area
The outline as issued.
The facts
- Issued
- Nov 10, 2021, 5:06 PM CST (23:06 UTC)
- Expired
- Nov 10, 2021, 7:00 PM CST
- In force
- 114 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch likely
- Chance of a watch
- 80%
All 36 counties
Bryan County, OK, Carter County, OK, Choctaw County, OK, Cotton County, OK, Jefferson County, OK, Love County, OK, Marshall County, OK, Archer County, TX, Clay County, TX, Collin County, TX, Cooke County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Fannin County, TX, Franklin County, TX, Grayson County, TX, Hopkins County, TX, Hunt County, TX, Jack County, TX, Kaufman County, TX, Lamar County, TX, Montague County, TX, Palo Pinto County, TX, Parker County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Stephens County, TX, Tarrant County, TX, Titus County, TX, Van Zandt County, TX, Wichita County, TX, Wise County, TX, Wood County, TX, Young County, TX
The radar
The Dallas/Ft Worth radar (KFWS), 98 km from the middle of the area, began a volume at 23:07 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Fort Worth, TX (KFWD), launched 12:00Z, 11.1 hours before the alert went out and 70 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
- 4 J/kg
- Mixed-layer CIN
- -49 J/kg
- Mixed-layer LCL
- 620 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 48 m²/s²
- 0-3 km storm-relative helicity
- 41 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.1
The text
As transmitted.
309
ACUS11 KWNS 102306
SWOMCD
SPC MCD 102306
OKZ000-TXZ000-110100-
Mesoscale Discussion 1937
NWS Storm Prediction Center Norman OK
0506 PM CST Wed Nov 10 2021
Areas affected...parts of north Texas
Concerning...Severe potential...Watch likely
Valid 102306Z - 110100Z
Probability of Watch Issuance...80 percent
SUMMARY...Storms capable of damaging hail, strong gusts and perhaps
a brief tornado are expected to affect parts of north Texas this
evening.
DISCUSSION...Surface analysis shows a cold front from central OK
into northwest TX, with a dryline from near Wichita Falls extending
southwestward toward San Angelo. While dewpoints are only in the
55-60 F range, temperatures aloft are quite cold which is maximizing
instability. A 21Z sounding from OUN showed 2000 J/kg MUCAPE,
despite little heating today.
Visible imagery shows towering CU near the cold front/dryline
intersection approaching the Wichita Falls area. One or more
supercells may eventually form out of this area, with storms
forecast to progress east/southeastward this evening.
Lengthening hodographs as well as steep lapse rates aloft with 500
mb temperatures near -17 C suggest damaging hail will be possible as
storms move east/southeast along and south of the Red River. A brief
tornado may occur as well, as low-level shear remains favorable
prior to the cold front passing. However, low-level winds are
forecast to rapidly veer this evening.
..Jewell/Edwards.. 11/10/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...SHV...TSA...FWD...OUN...
LAT...LON 34289674 34109555 33929504 33529492 33029494 32659544
32429606 32389696 32479793 32579891 32849899 33269877
33689878 34259895 34499858 34429769 34289674SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Nov 10, 1:26 PM CST | Mesoscale Discussion | SPC | Caddo, Canadian, Cleveland, Comanche, Creek, Garfield and 17 more | 2 hr |
| Nov 10, 3:26 PM CST | Severe Thunderstorm Watch | SPC | Adair, Atoka, Bryan, Caddo, Canadian, Carter and 48 more | 7 hr |
| Nov 10, 5:56 PM CST | Severe Thunderstorm Watch | SPC | Collin, Cooke, Dallas, Delta, Denton, Ellis and 15 more | 7 hr |
Nearby
Mesoscale Discussions in Texas, 2021Mesoscale Discussions in Oklahoma, 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.