Alert archive / Texas / Mesoscale Discussions in 2016
Mesoscale Discussion 428
The Storm Prediction Center issued this mesoscale discussion at Apr 20, 2016, 11:35 PM CDT for 11 counties in Texas. It was in force for 55 min.
The area
The outline as issued.
The facts
- Issued
- Apr 20, 2016, 11:35 PM CDT (04:35 UTC)
- Expired
- Apr 21, 2016, 12:30 AM CDT
- In force
- 55 min
- Issued by
- the Storm Prediction Center
Counties Crosby County, TX, Fisher County, TX, Garza County, TX, Haskell County, TX, Jones County, TX, Kent County, TX, Lubbock County, TX, Lynn County, TX, Scurry County, TX, Shackelford County, TX, Stonewall County, TX
The radar
The Dyess AFB radar (KDYX), 125 km from the middle of the area, began a volume at 04:36 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
Midland Regional, TX (KMAF), launched 00:00Z, 4.6 hours before the alert went out and 211 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
- 1 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2940 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- -1 m²/s²
- 0-3 km storm-relative helicity
- 97 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
216
ACUS11 KWNS 210436
SWOMCD
SPC MCD 210435
TXZ000-210530-
MESOSCALE DISCUSSION 0428
NWS STORM PREDICTION CENTER NORMAN OK
1135 PM CDT WED APR 20 2016
AREAS AFFECTED...BIG COUNTRY OF NORTHWEST TX
CONCERNING...SEVERE THUNDERSTORM WATCH 99...
VALID 210435Z - 210530Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 99
CONTINUES.
SUMMARY...A RISK FOR ISOLATED SEVERE HAIL SHOULD PERSIST FOR AT
LEAST A FEW MORE HOURS ACROSS A CONFINED PORTION OF THE BIG COUNTRY.
OVERALL THREAT DOES NOT APPEAR SUFFICIENT FOR AN ADDITIONAL
DOWNSTREAM WW...BUT ANOTHER LOCAL EXTENSION BY WFO SJT IS POSSIBLE.
DISCUSSION...CONVECTIVE OUTFLOW HAS SURGED AROUND 20 MILES AHEAD OF
THE ELEVATED CLUSTER CENTERED ON THE SOUTHEAST PART OF THE LUB CWA.
NEVERTHELESS...A FEW STRONG TO SEVERE CORES PERSIST BEHIND THE
OUTFLOW WITH ADDITIONAL DEVELOPMENT OCCURRING UPSHEAR NEAR LUBBOCK.
PREDOMINANT CLUSTER MODE SHOULD CONTINUE TO LIMIT THE MAGNITUDE OF
HAIL SIZE...BUT 40-45 KT LOW-LEVEL SOUTHERLIES BENEATH 35-40 KT
MID-LEVEL WESTERLIES /PER AREA VWP DATA/ WILL SUPPORT POTENTIAL FOR
SPORADIC OCCURRENCES OF SEVERE HAIL. CONVECTIVE TRENDS SUGGEST
ACTIVITY SHOULD CONTINUE SOUTH-SOUTHEAST ALONG THE INSTABILITY
GRADIENT TOWARDS THE ABILENE AREA THROUGH ABOUT 07Z...AND GRADUALLY
WEAKEN IN OVERALL INTENSITY LATER IN THE MORNING AS THE LLJ BEGINS
TO SUBSIDE/VEER.
..GRAMS.. 04/21/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...FWD...OUN...SJT...LUB...MAF...
LAT...LON 33610002 33309949 32889910 32519900 32319943 32380029
32490082 32800156 33430201 33720185 33640117 33590057
33610002SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 20, 8:17 PM CDT | Severe Thunderstorm Watch | SPC | Armstrong, Baylor, Briscoe, Carson, Childress, Collingsworth and 23 more | 6 hr |
| Apr 20, 8:22 PM CDT | Mesoscale Discussion | SPC | Duval, Jim Hogg, Starr, Webb, Zapata | 83 min |
| Apr 20, 9:40 PM CDT | Mesoscale Discussion | SPC | Cottle, Crosby, Dickens, Fisher, Foard, Garza and 7 more | 65 min |
| Apr 21, 1:16 AM CDT | Mesoscale Discussion | SPC | Borden, Callahan, Coke, Coleman, Dawson, Fisher and 19 more | 89 min |
| Apr 21, 1:44 AM CDT | Severe Thunderstorm Watch | SPC | Borden, Coke, Dawson, Gaines, Glasscock, Howard and 7 more | 4 hr |
| Apr 21, 4:57 AM CDT | Mesoscale Discussion | SPC | Coke, Coleman, Concho, Runnels, Taylor, Tom Green | 93 min |
| Apr 21, 9:40 AM CDT | Mesoscale Discussion | SPC | Brazoria, Chambers, Hardin, Liberty, Tyler | 2 hr |
| Apr 21, 2:14 PM CDT | Mesoscale Discussion | SPC | Cameron, Hidalgo, Kenedy, Willacy | 2 hr |
| Apr 21, 2:36 PM CDT | Mesoscale Discussion | SPC | Brewster, Crockett, Edwards, Pecos, Terrell, Val Verde | 2 hr |
Nearby
Mesoscale Discussions in Texas, 2016Every mesoscale discussion in 2016
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.