Alert archive / Texas / Mesoscale Discussions in 2017
Mesoscale Discussion 511
The Storm Prediction Center issued this mesoscale discussion at Apr 16, 2017, 9:06 PM CDT for 15 counties in Texas. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 16, 2017, 9:06 PM CDT (02:06 UTC)
- Expired
- Apr 16, 2017, 11:30 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
Counties Coke County, TX, Crockett County, TX, Dimmit County, TX, Edwards County, TX, Glasscock County, TX, Irion County, TX, Kinney County, TX, Maverick County, TX, Mitchell County, TX, Reagan County, TX, Sterling County, TX, Sutton County, TX, Uvalde County, TX, Val Verde County, TX, Zavala County, TX
The radar
The Laughlin AFB radar (KDFX), 70 km from the middle of the area, began a volume at 02:07 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 nearest sounding before it
Del Rio, TX (KDLF), launched 00:00Z, 2.1 hours before the alert went out and 65 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
- 2034 J/kg
- Mixed-layer CIN
- -61 J/kg
- Mixed-layer LCL
- 1078 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 16 m²/s²
- 0-3 km storm-relative helicity
- 34 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
130
ACUS11 KWNS 170207
SWOMCD
SPC MCD 170206
TXZ000-170430-
Mesoscale Discussion 0511
NWS Storm Prediction Center Norman OK
0906 PM CDT Sun Apr 16 2017
Areas affected...Part of southwest TX to the lower Rio Grande Valley
Concerning...Severe potential...Watch unlikely
Valid 170206Z - 170430Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated large hail and strong wind gusts will be possible
with strong/sustained storms this evening across primarily a portion
of the lower Rio Grande Valley in the northwest Brush Country of
South Texas. Farther north into Val Verde to Glasscock Counties,
overall severe-weather threat should be lower than in South Texas.
DISCUSSION...Mosaic radar and satellite imagery showed rapid
thunderstorm development in northwest portion of South TX from
Dimmit County to Kinney and Uvalde Counties. The presence of
moderate-strong instability (MLCAPE 2500-3000 J/kg per RAP
mesoanalysis and 00z DRT sounding) and steep 3-6 km lapse rates
exceeding 8 C/km per southwest and south TX 00Z soundings suggest
large hail will be possible with the sustained updrafts. The
potential for watch issuance is low, since weak bulk shear and weak
winds in the 700-500 mb layer per 00Z soundings should limit overall
storm organization to sustain greater severe-weather risk.
Farther north/northwest, storms moving through portions of the
Edwards Plateau and located between KMAF and KSJT are undergoing a
weakening trend per CAPPI data and objective analyses showing
increasing surface-based inhibition. This would suggest a
severe-weather threat will continue to diminish with this activity.
..Peters/Hart.. 04/17/2017
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...CRP...EWX...SJT...MAF...
LAT...LON 28560034 29480102 29990167 30950180 32090166 32420107
32290057 30720058 29969991 29129943 28419930 27849945
27839991 28560034SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 16, 7:01 PM CDT | Mesoscale Discussion | SPC | Armstrong, Briscoe, Childress, Collingsworth, Cottle, Crosby and 25 more | 59 min |
| Apr 16, 9:33 PM CDT | Mesoscale Discussion | SPC | Armstrong, Briscoe, Childress, Collingsworth, Cottle, Crosby and 26 more | 57 min |
| Apr 17, 2:40 AM CDT | Mesoscale Discussion | SPC | Brooks, Duval, Jim Hogg, Jim Wells, Kenedy, Kleberg and 3 more | 3 hr |
| Apr 17, 4:50 PM CDT | Mesoscale Discussion | SPC | Brooks, Duval, Jim Hogg, Jim Wells, Kenedy, Kleberg and 4 more | 115 min |
Nearby
Mesoscale Discussions in Texas, 2017Every mesoscale discussion in 2017
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.