Alert archive / Texas / Mesoscale Discussions in 2004
Mesoscale Discussion 488
The Storm Prediction Center issued this mesoscale discussion at Apr 28, 2004, 7:07 PM CDT for 14 counties in Texas. It was in force for 83 min.
The area
The outline as issued.
The facts
- Issued
- Apr 28, 2004, 7:07 PM CDT (00:07 UTC)
- Expired
- Apr 28, 2004, 8:30 PM CDT
- In force
- 83 min
- Issued by
- the Storm Prediction Center
Counties Bandera County, TX, Dimmit County, TX, Edwards County, TX, Frio County, TX, Kerr County, TX, Kinney County, TX, La Salle County, TX, Maverick County, TX, Medina County, TX, Real County, TX, Uvalde County, TX, Val Verde County, TX, Webb County, TX, Zavala County, TX
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Del Rio, TX (KDRT), launched 00:00Z, 0.1 hours before the alert went out and 74 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
- 850 J/kg
- Mixed-layer CIN
- -10 J/kg
- Mixed-layer LCL
- 912 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 97 m²/s²
- 0-3 km storm-relative helicity
- 198 m²/s²
- Significant tornado parameter
- 0.8
- Supercell composite
- 5.8
The text
As transmitted, in the capitals the NWS used until 2016.
734 ACUS11 KWNS 290007 SWOMCD SPC MCD 290007 TXZ000-290130- MESOSCALE DISCUSSION 0488 NWS STORM PREDICTION CENTER NORMAN OK 0707 PM CDT WED APR 28 2004 AREAS AFFECTED...SW TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL/OUTLOOK UPGRADE VALID 290007Z - 290130Z SEVERE WIND/HAIL POSSIBLE IN SW TX ALONG THE RIO GRANDE THIS EVENING...TRENDS ARE BEING MONITORED FOR POSSIBLE SEVERE WATCH. 01Z OUTLOOK WILL BE UPGRADED TO CATEGORICAL SLIGHT RISK FOR MUCH OF THE RIO GRANDE VALLEY. AS SHORTWAVE TROUGH NEAR BIG BEND REGION CONTINUES TO MOVE EWD THIS EVENING...POSSIBILITY WILL EXIST FOR ISOLD LARGE HAIL/DAMAGING WINDS ACROSS THE RIO GRANDE VALLEY AS TSTMS DEVELOP AND/OR PROPAGATE OUT OF MEXICO. LATEST OBJECTIVE ANALYSIS PORTRAYS INSTABILITY AXIS ALONG THE RIO GRANDE VALLEY WITH MLCAPE ON THE ORDER OF 500-1000 J/KG. MODERATE LOW LEVEL SE WINDS WILL CONTRIBUTE TO CURVED HODOGRAPHS AND DEEP LAYER SHEAR /0-6 KM/ OF 40-45 KTS...SUPPORTIVE OF STORM ORGANIZATION THROUGH THE EVENING...INCLUDING A FEW SUPERCELLS AND/OR FORWARD PROPAGATING MCS. ..GUYER.. 04/29/2004 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CRP...EWX...SJT... 29880164 30510027 30159931 28559858 27529890 27589956 28510043 29160102
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 28, 7:25 PM CDT | Severe Thunderstorm Watch | SPC | Bandera, Brooks, Crockett, Dimmit, Duval, Edwards and 17 more | 6 hr |
| Apr 28, 9:56 PM CDT | Mesoscale Discussion | SPC | Atascosa, Bandera, Brooks, Dimmit, Duval, Edwards and 12 more | 94 min |
| Apr 29, 4:12 AM CDT | Mesoscale Discussion | SPC | Austin, Bastrop, Brazos, Burleson, Colorado, DeWitt and 18 more | 3 hr |
| Apr 29, 1:10 PM CDT | Tornado Watch | SPC | Shelby | 6 hr |
| Apr 29, 1:49 PM CDT | Mesoscale Discussion | SPC | Baylor, Childress, Collingsworth, Cottle, Foard, Hall and 4 more | 116 min |
| Apr 29, 3:05 PM CDT | Severe Thunderstorm Watch | SPC | Childress, Collingsworth, Cottle, Crosby, Dickens, Foard and 7 more | 7 hr |
| Apr 29, 3:58 PM CDT | Mesoscale Discussion | SPC | Borden, Coke, Crockett, Fisher, Glasscock, Howard and 15 more | 2 hr |
| Apr 29, 5:10 PM CDT | Mesoscale Discussion | SPC | Archer, Baylor, Callahan, Clay, Coke, Coleman and 18 more | 95 min |
| Apr 29, 5:35 PM CDT | Severe Thunderstorm Watch | SPC | Archer, Baylor, Callahan, Clay, Fisher, Haskell and 10 more | 5 hr |
| Apr 29, 6:35 PM CDT | Mesoscale Discussion | SPC | Childress, Collingsworth, Cottle, Crosby, Dickens, Foard and 7 more | 85 min |
Nearby
Mesoscale Discussions in Texas, 2004Every mesoscale discussion in 2004
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.