Alert archive / Texas / Mesoscale Discussions in 2004

Mesoscale Discussion 142

February 29, 200427 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Feb 29, 2004, 7:33 AM CST for 27 counties in Texas. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued: Feb 29, 2004, 7:33 AM CST (13:33 UTC)
Expired: Feb 29, 2004, 9:30 AM CST
In force: 117 min
Issued by: the Storm Prediction Center

All 27 counties

Bell County, TX, Bosque County, TX, Collin County, TX, Cooke County, TX, Coryell County, TX, Dallas County, TX, Denton County, TX, Ellis County, TX, Falls County, TX, Freestone County, TX, Grayson County, TX, Hamilton County, TX, Henderson County, TX, Hill County, TX, Hood County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Limestone County, TX, McLennan County, TX, Navarro County, TX, Parker County, TX, Rockwall County, TX, Somervell County, TX, Tarrant County, TX, Van Zandt County, TX, Wise County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 24 km from the middle of the area, began a volume at 13:35 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

Fort Worth, TX (KFWD), launched 12:00Z, 1.6 hours before the alert went out and 41 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 457 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 556 m²/s²
0-3 km storm-relative helicity: 698 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
ACUS11 KWNS 291333
SWOMCD
SPC MCD 291333 
TXZ000-OKZ000-291530-

MESOSCALE DISCUSSION 0142
NWS STORM PREDICTION CENTER NORMAN OK
0733 AM CST SUN FEB 29 2004

AREAS AFFECTED...N-CNTRL TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 291333Z - 291530Z

THE POTENTIAL FOR ISOLATED WIND GUSTS APPROACHING SEVERE LIMITS WILL
BE POSSIBLE WITH CONVECTIVE LINE THROUGH MID MORNING.

AS OF 1315Z...FT. WORTH 88D REFLECTIVITY DATA INDICATED SQUALL LINE
FROM S-CNTRL MONTAGUE COUNTY SWD INTO ERN HAMILTON COUNTY MOVING EWD
AT 30-35KTS. THIS LINE HAS ACCELERATED SLIGHTLY OVER THE PAST HOUR
WITH SOME SMALLER SCALE BOWING STRUCTURES OBSERVED NEAR MWL WHICH
REPORTED A 41KT GUST AT 1252Z. ALTHOUGH THE 12Z FT. WORTH SOUNDING
INDICATED ONLY WEAK INSTABILITY...INTENSE LARGE-SCALE FORCING AHEAD
OF MID-LEVEL SHORTWAVE TROUGH TRANSLATING NEWD THROUGH WRN/SWRN TX
COUPLED WITH STRONG LOW-LEVEL CONVERGENCE ALONG SURFACE DRYLINE
SHOULD MAINTAIN CONVECTIVE LINE EWD THROUGH THE METROPLEX BY
1400-1430Z AND INTO ERN PORTIONS OF N TX BY MID TO LATE MORNING.

ALTHOUGH A LARGER-SCALE DAMAGING WIND EVENT DOES NOT APPEAR LIKELY
OWING TO THE WEAK INSTABILITY AND THE MERIDIONAL NATURE OF LOWER TO
MID-TROPOSPHERIC WINDS /WHICH ARE ORIENTED PARALLEL TO ONGOING
CONVECTIVE LINE/...AN ISOLATED SEVERE WIND GUST OR TWO WILL BE
POSSIBLE WITH ANY EMBEDDED SMALLER SCALE BOWING SEGMENTS.

..MEAD.. 02/29/2004

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...FWD...OUN...

33329785 33759760 33719678 33539604 32509572 31689594
30859683 31099769 31409826

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 28, 8:24 PM CST	Mesoscale Discussion	SPC	Andrews, Borden, Coke, Crane, Crockett, Dawson and 16 more	3 hr
Feb 29, 1:11 AM CST	Mesoscale Discussion	SPC	Brown, Callahan, Coke, Coleman, Concho, Crockett and 15 more	3 hr

Nearby

Mesoscale Discussions in Texas, 2004 Every 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; radar from the NEXRAD Level II archive.