Alert archive / Texas / Mesoscale Discussions in 2004
Mesoscale Discussion 75
The Storm Prediction Center issued this mesoscale discussion at Feb 4, 2004, 3:22 PM CST for 9 counties in Texas. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 4, 2004, 3:22 PM CST (21:22 UTC)
- Expired
- Feb 4, 2004, 5:45 PM CST
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
Counties Aransas County, TX, Brazoria County, TX, Calhoun County, TX, Jackson County, TX, Matagorda County, TX, Refugio County, TX, San Patricio County, TX, Victoria County, TX, Wharton County, TX
The nearest sounding before it
Corpus Christi, TX (KCRP), launched 12:00Z, 9.4 hours before the alert went out and 120 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
- 121 J/kg
- Mixed-layer CIN
- -251 J/kg
- Mixed-layer LCL
- 714 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 277 m²/s²
- 0-3 km storm-relative helicity
- 498 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted, in the capitals the NWS used until 2016.
666 ACUS11 KWNS 042122 SWOMCD SPC MCD 042122 TXZ000-042345- MESOSCALE DISCUSSION 0075 NWS STORM PREDICTION CENTER NORMAN OK 0322 PM CST WED FEB 04 2004 AREAS AFFECTED...MIDDLE TX COAST CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 042122Z - 042345Z THE POTENTIAL FOR SURFACE-BASED TSTM DEVELOPMENT IS EXPECTED TO INCREASE ACROSS THE MIDDLE AND UPPER TX COAST THROUGH THE LATE AFTERNOON AND EARLY EVENING HOURS. CONVECTIVE TRENDS WILL BE MONITORED AND A WW MAY BE REQUIRED. LATEST SURFACE ANALYSIS AND VISIBLE SATELLITE IMAGERY SHOW BOUNDARY DELIMITING NWRN EDGE OF MARITIME TROPICAL AIRMASS FROM NEAR BUOY 42020 /APPROXIMATELY 80SE CRP/ TO AROUND 50 SE GLS LIFTING NWD AT 25-30KTS. CONVERGENCE INVOF THIS BOUNDARY WITHIN WEAKLY CAPPED AND MODERATELY UNSTABLE ENVIRONMENT HAVE ALLOWED SEVERAL TSTMS TO DEVELOP THIS AFTERNOON OVER THE NWRN GULF...INCLUDING A SUPERCELL 70SSE GLS. PRESSURE FALLS AHEAD OF 110-120KT UPPER-LEVEL JET STREAK TRANSLATING EWD OUT OF NRN MEXICO SHOULD SUSTAIN NWD MOVEMENT OF WARM FRONT/MARINE BOUNDARY WITH EXTRAPOLATION PLACING THIS FEATURE INVOF MIDDLE AND UPPER TX COAST BETWEEN 2130 AND 2230Z. IT APPEARS THAT THE SURFACE WARM SECTOR WILL REMAIN OFFSHORE FOR THE NEXT FEW HOURS FROM ABOUT GLS EWD...WHERE THE TROPICAL MOISTURE SURGE IS LIKELY SPREADING NWD ABOVE THE NEAR SURFACE COOL AIR MASS. EXPECT THE POTENTIAL FOR SURFACE-BASED TSTMS TO INCREASE ALONG THE COAST FROM VCT TO GLS OVER THE NEXT SEVERAL HOURS AS MODERATELY UNSTABLE AIRMASS /CHARACTERIZED BY MLCAPES OF 500-1500 J/KG/ SPREADS INLAND. ALTHOUGH SURFACE WINDS WILL VEER TO SELY WITH PASSAGE OF BOUNDARY...SHEAR PROFILES WILL STILL REMAIN QUITE FAVORABLE FOR ISOLATED SUPERCELLS. IF IT BECOMES APPARENT THAT ANY DEVELOPING STORMS IN CLOSE PROXIMITY TO THE COAST ARE ROOTED NEAR THE SURFACE... A WW MAY BE REQUIRED. ..MEAD.. 02/04/2004 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...CRP... 27709727 27969759 28419742 28789705 29319638 29469567 29519518 29079512 27919697
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 4, 3:58 AM CST | Mesoscale Discussion | SPC | Lipscomb | 3 hr |
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.