Alert archive / Texas / Mesoscale Discussions in 2017
Mesoscale Discussion 736
The Storm Prediction Center issued this mesoscale discussion at May 16, 2017, 4:56 PM CDT for Collingsworth County, Wheeler County, Texas. It was in force for 64 min.
The area
The outline as issued.
The facts
- Issued
- May 16, 2017, 4:56 PM CDT (21:56 UTC)
- Expired
- May 16, 2017, 6:00 PM CDT
- In force
- 64 min
- Issued by
- the Storm Prediction Center
Counties Collingsworth County, TX, Wheeler County, TX
The radar
The Amarillo radar (KAMA), 124 km from the middle of the area, began a volume at 21:59 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, 9.9 hours before the alert went out and 123 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
- 837 J/kg
- Mixed-layer CIN
- -240 J/kg
- Mixed-layer LCL
- 1292 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 4 m²/s²
- 0-3 km storm-relative helicity
- 88 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted.
992 ACUS11 KWNS 162157 SWOMCD SPC MCD 162156 OKZ000-TXZ000-162300- Mesoscale Discussion 0736 NWS Storm Prediction Center Norman OK 0456 PM CDT Tue May 16 2017 Areas affected...east-central TX Panhandle Concerning...Tornado Watch 220... Valid 162156Z - 162300Z The severe weather threat for Tornado Watch 220 continues. SUMMARY...The risk for very large to giant hail (2-3.5 inches in diameter) and tornadoes will increase nonlinearly (22-00Z). A large/intense (EF3+ capable) tornado is possible (23-02Z) given the strengthening low-level shear, very large buoyancy, and the mature phase of a quasi-discrete supercell. DISCUSSION...Radar imagery shows a north-south cluster of supercells over the eastern TX Panhandle which have moved east of the dryline. OK and West TX mesonet observations show dewpoints in the 66-69 degrees F range and temperatures in the middle 70s to around 80. Very strong backing of low-level flow, perhaps partially induced by parent storms to the west, has enlarged the low-level hodograph size during the past 30 minutes from Childress County to Wheeler County with 2-4 mb/hour falls in the past 2 hours. RAP forecast soundings show 0-1 km SRH increasing from 150 m2/s2 to 350 m2/s2 (locally higher and augmented by storms) during the 22-00Z period. As the low-level shear continues to increase over the next couple of hours, expect with medium to higher confidence of a large/intense tornado ---potentially capable of EF3+ intensity--- evolving from supercell cluster in Wheeler/Gray/Collingsworth counties. ..Smith/Guyer.. 05/16/2017 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN...LUB...AMA... LAT...LON 35220072 35510031 35429986 34969988 34710057 35220072
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 16, 1:19 PM CDT | Mesoscale Discussion | SPC | Briscoe, Carson, Childress, Collingsworth, Donley, Gray and 7 more | 56 min |
| May 16, 1:54 PM CDT | Tornado Watch | SPC | Armstrong, Baylor, Briscoe, Carson, Childress, Collingsworth and 20 more | 8 hr |
| May 16, 3:36 PM CDT | Mesoscale Discussion | SPC | Armstrong, Briscoe, Carson, Childress, Collingsworth, Cottle and 15 more | 54 min |
| May 16, 5:29 PM CDT | Mesoscale Discussion | SPC | Borden, Coke, Crockett, Fisher, Garza, Glasscock and 14 more | 2 hr |
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.