Alert archive / Texas / Mesoscale Discussions in 2009

Mesoscale Discussion 1621

July 19, 20095 states

The Storm Prediction Center issued this mesoscale discussion at Jul 19, 2009, 5:34 PM MDT for 5 states. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued: Jul 19, 2009, 5:34 PM MDT (23:34 UTC)
Expired: Jul 19, 2009, 6:30 PM MDT
In force: 56 min
Issued by: the Storm Prediction Center

All 28 counties

Baca County, CO, Morton County, KS, Curry County, NM, De Baca County, NM, Guadalupe County, NM, Harding County, NM, Quay County, NM, Roosevelt County, NM, San Miguel County, NM, Union County, NM, Cimarron County, OK, Armstrong County, TX, Bailey County, TX, Carson County, TX, Castro County, TX, Dallam County, TX, Deaf Smith County, TX, Hansford County, TX, Hartley County, TX, Hutchinson County, TX, Lamb County, TX, Moore County, TX, Oldham County, TX, Parmer County, TX, Potter County, TX, Randall County, TX, Sherman County, TX, Swisher County, TX

The radar

The Amarillo radar (KAMA), 112 km from the middle of the area, began a volume at 23:36 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

Amarillo Airport, TX (KAMA), launched 12:00Z, 11.6 hours before the alert went out and 113 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: 187 J/kg
Mixed-layer CIN: -195 J/kg
Mixed-layer LCL: 1177 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 113 m²/s²
0-3 km storm-relative helicity: 139 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 192334
SWOMCD
SPC MCD 192334 
TXZ000-OKZ000-KSZ000-COZ000-NMZ000-200030-

MESOSCALE DISCUSSION 1621
NWS STORM PREDICTION CENTER NORMAN OK
0634 PM CDT SUN JUL 19 2009

AREAS AFFECTED...SERN CO...NERN NM...OK/TX PANHANDLES

CONCERNING...SEVERE THUNDERSTORM WATCH 604...

VALID 192334Z - 200030Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 604
CONTINUES.

PORTIONS OF THE OK/TX PANHANDLE ARE BEING CLOSELY MONITORED FOR THE
POSSIBILITY OF AN ADDITIONAL SEVERE TSTM WATCH OR AREAL EXTENSION OF
WW 604.

RECENT RADAR IMAGERY DEPICTED TSTM ACTIVITY PRIMARILY CONCENTRATED
ALONG THE SANGRE DE CRISTO MTNS AND ACROSS THE RATON MESA. THE
LATTER AREA HAS SHOWN INCREASED SIGNS OF AMALGAMATING OUTFLOWS AND
THIS MAY COMMENCE THE OVERALL TRANSITION FROM WHAT HAS BEEN A
MARGINALLY SEVERE HAIL THREAT INTO MORE OF A DAMAGING WIND THREAT
THIS EVENING. 23Z SUBJECTIVE SURFACE ANALYSIS PLACED A
QUASI-STATIONARY FRONTAL BOUNDARY FROM HARDING COUNTY NM SEWD TO
NEAR 40 SW CDS. VISIBLE SATELLITE IMAGERY DEPICTS A HEALTHY SC FIELD
NE OF THIS BOUNDARY ACROSS THE CNTRL/ERN TX PANHANDLE WHERE MIDDLE
TO UPPER 50S SURFACE DEW POINTS CONTRIBUTE TO A MODERATELY UNSTABLE
AIR MASS WITH MLCAPE AROUND 1500 J/KG. WITH STRONG DIRECTIONAL
VEERING FROM SLY FLOW AT THE SURFACE TO MODERATE NLY FLOW AOA 3 KM
AGL /PER AREA VWP AND PROFILER DATA/...AN ORGANIZED CONVECTIVE
CLUSTER MAY ULTIMATELY EVOLVE S/SEWD ACROSS FAR ERN NM INTO THE WRN
AND PERHAPS CNTRL PANHANDLES.

..GRAMS.. 07/19/2009

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

ATTN...WFO...DDC...LUB...AMA...PUB...ABQ...

LAT...LON   37560235 37440196 36980161 36220125 35370100 34750117
            34240135 33960219 33850320 34060472 34360506 34720526
            35470488 36680387 37300300 37560235

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 19, 1:08 PM MDT	Mesoscale Discussion	SPC	Bent, Crowley, Las Animas, Otero	2 hr
Jul 19, 1:50 PM MDT	Severe Thunderstorm Watch	SPC	Baca, Bent, Crowley, Huerfano, Kiowa, Las Animas and 3 more	7 hr
Jul 18, 8:05 PM MDT	Mesoscale Discussion	SPC	Lea	55 min
Jul 18, 6:22 PM MDT	Severe Thunderstorm Watch	SPC	Briscoe, Childress, Cochran, Cottle, Crosby, Dickens and 15 more	5 hr
Jul 19, 1:58 AM MDT	Mesoscale Discussion	SPC	Borden, Coke, Concho, Cottle, Crockett, Crosby and 25 more	2 hr
Jul 19, 1:06 PM MDT	Mesoscale Discussion	SPC	Anderson, Cherokee, Collin, Dallas, Denton, Ellis and 16 more	54 min
Jul 19, 1:36 PM MDT	Severe Thunderstorm Watch	SPC	Anderson, Angelina, Bell, Brazos, Burleson, Cherokee and 34 more	6 hr
Jul 19, 4:54 PM MDT	Mesoscale Discussion	SPC	Anderson, Angelina, Brazos, Burleson, Cherokee, Collin and 37 more	96 min

Nearby

Mesoscale Discussions in Texas, 2009 Mesoscale Discussions in New Mexico, 2009 Mesoscale Discussions in Colorado, 2009 Every mesoscale discussion in 2009

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.