Alert archive / Texas / Mesoscale Discussions in 2012
Mesoscale Discussion 558
The Storm Prediction Center issued this mesoscale discussion at Apr 16, 2012, 5:50 AM CDT for 5 counties in Texas. It was in force for 55 min.
The area
The outline as issued.
The facts
- Issued
- Apr 16, 2012, 5:50 AM CDT (10:50 UTC)
- Expired
- Apr 16, 2012, 6:45 AM CDT
- In force
- 55 min
- Issued by
- the Storm Prediction Center
Counties Aransas County, TX, Calhoun County, TX, Nueces County, TX, Refugio County, TX, San Patricio County, TX
The radar
The Corpus Christi radar (KCRP), 71 km from the middle of the area, began a volume at 10:49 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
Corpus Christi, TX (KCRP), launched 00:00Z, 10.8 hours before the alert went out and 59 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
- 3768 J/kg
- Mixed-layer CIN
- -73 J/kg
- Mixed-layer LCL
- 1113 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- -15 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.1
The text
As transmitted, in the capitals the NWS used until 2016.
563
ACUS11 KWNS 161050
SWOMCD
SPC MCD 161050
TXZ000-161145-
MESOSCALE DISCUSSION 0558
NWS STORM PREDICTION CENTER NORMAN OK
0550 AM CDT MON APR 16 2012
AREAS AFFECTED...MIDDLE TX COAST
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 161050Z - 161145Z
A MARGINAL TORNADO THREAT MAY EXIST FOR A FEW HOURS ACROSS THE
MIDDLE TX COAST EARLY THIS MORNING. HAIL AND STRONG GUSTY WINDS MAY
ALSO OCCUR. ALTHOUGH THE THREATS SHOULD REMAIN ISOLATED...WW
ISSUANCE CAN NOT BE RULED OUT. FOR THE OUTLOOK AT 13Z...A SLIGHT
RISK UPGRADE IS BEING CONSIDERED FOR THE LOWER TO MIDDLE TX COAST.
A SUPERCELL ONGOING TO THE NORTHWEST OF PORT ARANSAS IS LOCATED ON A
SFC FRONT WHERE MESOANALYSIS SHOWS ENHANCED LOW-LEVEL CONVERGENCE.
THE STORM IS BEING SUPPORTED BY A SHORTWAVE TROUGH EVIDENT IN WATER
VAPOR IMAGERY MOVING NEWD INTO THE WRN GULF OF MEXICO. CONCERNING
THE AIRMASS ON THE TX COAST...MODERATE INSTABILITY EXISTS WITH
MLCAPE OF ABOUT 1500 J/KG WITH WSR-88D VWPS ESTIMATING 0-6 KM SHEAR
OF 35 TO 45 KT. THIS ENVIRONMENT WILL SUPPORT SUPERCELL STRUCTURED
STORMS WITH A HAIL AND ISOLATED WIND DAMAGE THREAT. THE LOW-LEVEL
SHEAR MAY JUST BE STRONG ENOUGH FOR A BRIEF TORNADO OR TWO. THE
THREAT MAY CONTINUE FOR A FEW MORE HOURS AS THE STORMS PARALLEL THE
IMMEDIATE TX COAST.
..BROYLES.. 04/16/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...HGX...CRP...
LAT...LON 27909644 27539695 27449728 27589758 27959772 28539731
28769668 28729602 28169615 27909644SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 16, 8:07 AM CDT | Severe Thunderstorm Watch | SPC | Aransas, Bee, Brooks, Calhoun, Cameron, Goliad and 10 more | 7 hr |
| Apr 16, 12:06 PM CDT | Mesoscale Discussion | SPC | Aransas, Bee, Brooks, Calhoun, Cameron, DeWitt and 14 more | 84 min |
| Apr 16, 2:23 PM CDT | Mesoscale Discussion | SPC | Brooks, Cameron, Hidalgo, Kenedy, Willacy | 67 min |
| Apr 16, 3:28 PM CDT | Severe Thunderstorm Watch | SPC | Cameron, Hidalgo, Kenedy, Willacy | 4 hr |
Nearby
Mesoscale Discussions in Texas, 2012Every mesoscale discussion in 2012
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.