Alert archive / Texas / Mesoscale Discussions in 2011
Mesoscale Discussion 844
The Storm Prediction Center issued this mesoscale discussion at May 21, 2011, 7:34 PM CDT for 16 counties in Texas. It was in force for 86 min.
The area
The outline as issued.
The facts
- Issued
- May 21, 2011, 7:34 PM CDT (00:34 UTC)
- Expired
- May 21, 2011, 9:00 PM CDT
- In force
- 86 min
- Issued by
- the Storm Prediction Center
Counties Bell County, TX, Blanco County, TX, Burnet County, TX, Coryell County, TX, Gillespie County, TX, Hamilton County, TX, Kerr County, TX, Kimble County, TX, Lampasas County, TX, Llano County, TX, Mason County, TX, McLennan County, TX, Mills County, TX, Real County, TX, San Saba County, TX, Williamson County, TX
The radar
The Austin/San Antonio radar (KEWX), 123 km from the middle of the area, began a volume at 00:33 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 (KDRT), launched 00:00Z, 0.6 hours before the alert went out and 252 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
- 1814 J/kg
- Mixed-layer CIN
- -23 J/kg
- Mixed-layer LCL
- 2284 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- -24 m²/s²
- 0-3 km storm-relative helicity
- 81 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.0
The text
As transmitted, in the capitals the NWS used until 2016.
395
ACUS11 KWNS 220034
SWOMCD
SPC MCD 220034
TXZ000-220200-
MESOSCALE DISCUSSION 0844
NWS STORM PREDICTION CENTER NORMAN OK
0734 PM CDT SAT MAY 21 2011
AREAS AFFECTED...CENTRAL TX
CONCERNING...SEVERE THUNDERSTORM WATCH 316...
VALID 220034Z - 220200Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 316
CONTINUES.
CLUSTER OF SUPERCELLS CONTINUES ACROSS CENTRAL TX.
LATEST RADAR LOOP SHOWS A CLUSTER OF SUPERCELLS PERSISTING ACROSS
CENTRAL TX ATTM...WITH THE MOST SUBSTANTIAL STORM NOW OVER BURNET
CO. THESE STORMS HAVE SHOWN LITTLE DESIRE TO SHIFT EWD TOWARD THE
ERN FRINGE OF THE WATCH. HOWEVER...VISIBLE SATELLITE SHOWS THAT
THIS CLUSTER HAS SENT AN OUTFLOW BOUNDARY SWWD ALONG THE DRYLINE --
WITH MORE PRONOUNCED CU AGITATION EVIDENT AS THIS BOUNDARY MOVES
THROUGH THE DRYLINE CU FIELD. THIS COULD EVENTUALLY RESULT IN STORM
DEVELOPMENT W OF THE ONGOING CLUSTER -- NEAR THE WRN FRINGE OF THE
WW. WITH THIS AND OTHER SIGNS SUGGESTING POTENTIAL FOR STORMS TO
LINGER BEYOND THE SCHEDULED 22/02Z EXPIRATION...LOCAL EXT OR NEW WW
MAY NEED TO BE CONSIDERED.
..GOSS.. 05/22/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...FWD...EWX...SJT...
LAT...LON 29809986 30240009 31199928 31949781 31519694 30649733
30089832 29809986SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 22, 12:42 PM CDT | Mesoscale Discussion | SPC | Brown, Callahan, Coke, Coleman, Comanche, Concho and 13 more | 2 hr |
| May 22, 1:47 PM CDT | Tornado Watch | SPC | Bosque, Clay, Collin, Comanche, Cooke, Dallas and 19 more | 7 hr |
| May 22, 2:48 PM CDT | Severe Thunderstorm Watch | SPC | Brewster, Brown, Callahan, Coke, Coleman, Concho and 25 more | 7 hr |
| May 22, 3:47 PM CDT | Mesoscale Discussion | SPC | Cooke, Jack, Montague, Palo Pinto, Parker, Stephens and 2 more | 58 min |
| May 22, 6:34 PM CDT | Mesoscale Discussion | SPC | Callahan, Clay, Collin, Cooke, Dallas, Denton and 14 more | 56 min |
| May 22, 6:56 PM CDT | Mesoscale Discussion | SPC | Brewster, Brown, Callahan, Coke, Coleman, Concho and 25 more | 64 min |
Nearby
Mesoscale Discussions in Texas, 2011Every mesoscale discussion in 2011
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.