Alert archive / Texas / Mesoscale Discussions in 2017

Mesoscale Discussion 2

January 1, 201741 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jan 1, 2017, 10:11 PM CST for 41 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Jan 1, 2017, 10:11 PM CST (04:11 UTC)
Expired
Jan 2, 2017, 12:45 AM CST
In force
3 hr
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 41 counties

Archer County, TX, Baylor County, TX, Bosque County, TX, Brown County, TX, Callahan County, TX, Coleman County, TX, Comanche County, TX, Concho County, TX, Eastland County, TX, Edwards County, TX, Erath County, TX, Gillespie County, TX, Hamilton County, TX, Haskell County, TX, Hood County, TX, Jack County, TX, Johnson County, TX, Jones County, TX, Kerr County, TX, Kimble County, TX, Lampasas County, TX, Llano County, TX, Mason County, TX, McCulloch County, TX, Menard County, TX, Mills County, TX, Palo Pinto County, TX, Parker County, TX, Runnels County, TX, San Saba County, TX, Schleicher County, TX, Shackelford County, TX, Somervell County, TX, Stephens County, TX, Sutton County, TX, Tarrant County, TX, Taylor County, TX, Throckmorton County, TX, Tom Green County, TX, Wise County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 86 km from the middle of the area, began a volume at 04:12 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

Fort Worth, TX (KFWD), launched 00:00Z, 4.2 hours before the alert went out and 223 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-pSkew-T log-p diagram, Fort Worth, TX at 00:00Z on 2017-01-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Worth, TX at 00:00Z on 2017-01-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 98 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1528 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
98 m²/s²
0-3 km storm-relative helicity
160 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

337 
ACUS11 KWNS 020412
SWOMCD
SPC MCD 020411 
TXZ000-020645-

Mesoscale Discussion 0002
NWS Storm Prediction Center Norman OK
1011 PM CST Sun Jan 01 2017

Areas affected...Much of Central Texas

Concerning...Severe potential...Watch possible 

Valid 020411Z - 020645Z

Probability of Watch Issuance...60 percent

SUMMARY...Thunderstorms will increase in coverage and intensity
later tonight, with damaging winds and hail expected. A watch may be
needed prior to 06Z.

DISCUSSION...A rapidly moving cold front continues to move eastward
across West TX, with several wind gusts in excess of 40-50 kts
measured and only sporadic lightning. This front will gradually
interact with an increasingly unstable air mass, still well to the
east as of 04Z. However, increasing flow in the low levels just
above the surface will help transport mid to upper 50s dewpoints
northward out of South TX, with a rapid uptick in storms along the
front expected as MUCAPE of 500-1000 j/kg develops. This in turn
should allow for a line of storms along the front, with both wind
and hail possible.

..Jewell/Hart.. 01/02/2017

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...FWD...OUN...EWX...SJT...

LAT...LON   30219873 29730024 30030135 30720124 31520065 32510009
            33659960 33849866 33629781 33029711 32099731 30219873

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 2, 1:04 AM CSTMesoscale DiscussionSPCAnderson, Austin, Bandera, Bastrop, Bell, Bexar and 71 more86 min
Jan 2, 1:39 AM CSTSevere Thunderstorm WatchSPCAnderson, Austin, Bastrop, Bell, Blanco, Bosque and 67 more59 days
Jan 2, 2:06 AM CSTMesoscale DiscussionSPCJasper, Newton, Orange, Sabine, San Augustine, Shelby and 1 more114 min
Jan 2, 3:36 AM CSTMesoscale DiscussionSPCAnderson, Bastrop, Bell, Blanco, Bosque, Brazos and 44 more54 min
Jan 2, 5:35 AM CSTMesoscale DiscussionSPCAnderson, Angelina, Austin, Brazos, Burleson, Camp and 56 more85 min
Jan 2, 6:12 AM CSTTornado WatchSPCAngelina, Bowie, Camp, Cass, Cherokee, Franklin and 21 more10 hr
Jan 2, 7:48 AM CSTMesoscale DiscussionSPCAngelina, Bowie, Camp, Cass, Chambers, Cherokee and 25 more57 min

Nearby

Mesoscale Discussions in Texas, 2017Every mesoscale discussion in 2017

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.