Alert archive / Colorado / Mesoscale Discussions in 2012

Mesoscale Discussion 496

April 11, 20127 counties in Colorado

The Storm Prediction Center issued this mesoscale discussion at Apr 11, 2012, 10:50 PM MDT for 7 counties in Colorado. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: Apr 11, 2012, 10:50 PM MDT (04:50 UTC)
Expired: Apr 12, 2012, 12:15 AM MDT
In force: 85 min
Issued by: the Storm Prediction Center

Counties Crowley County, CO, Douglas County, CO, El Paso County, CO, Elbert County, CO, Jefferson County, CO, Pueblo County, CO, Teller County, CO

The radar

The Pueblo radar (KPUX), 71 km from the middle of the area, began a volume at 04:53 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

Denver, CO (KDNR), launched 00:00Z, 4.8 hours before the alert went out and 174 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: 265 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 1416 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 65 m²/s²
0-3 km storm-relative helicity: 169 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.

434 
ACUS11 KWNS 120451
SWOMCD
SPC MCD 120450
COZ000-120615-

MESOSCALE DISCUSSION 0496
NWS STORM PREDICTION CENTER NORMAN OK
1150 PM CDT WED APR 11 2012

AREAS AFFECTED...CO

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 120450Z - 120615Z

A LINE OF STORMS WILL LIKELY CONTINUE TO PRODUCE GUSTY WINDS/SOME
HAIL OVER THE NEXT HOUR OR TWO ACROSS EAST-CENTRAL CO/FRONT RANGE
VICINITY.

A LINEAR BAND OF STORMS HAS INCREASED IN INTENSITY/ORGANIZATION OVER
THE PAST HOUR ACROSS SOUTH-CENTRAL CO...NORTHWEST OF
PUEBLO/SOUTHWEST OF COLORADO SPRINGS. THIS ACTIVITY APPEARS TO
COINCIDE WITH THE LEADING EDGE OF FORCING FOR ASCENT/HEIGHT FALLS
ALOFT IN TANDEM WITH A FRONTAL SURGE/STRENGTHENING WINDS ALOFT.
GIVEN THE FORWARD MOTION OF THE LINE...STRONG/GUSTY WINDS AND SOME
HAIL SEEM VERY LIKELY INTO THE I-25 CORRIDOR INCLUDING AREAS
NEAR/BETWEEN COLORADO SPRINGS-PUEBLO OVER THE NEXT HOUR. BEYOND
THAT...THE SPECIFIC EVOLUTION IS UNCERTAIN OVERNIGHT...BUT THE
STORMS WILL INCREASINGLY ENCOUNTER A MORE STABLE AIRMASS ACROSS THE
HIGH PLAINS OF CO SUCH THAT A WEAKENING TREND SEEMS PROBABLE.

..GUYER.. 04/12/2012

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

ATTN...WFO...PUB...BOU...

LAT...LON   39430548 39770532 39440392 38100352 37530472 38470517
            39430548

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 12, 12:24 PM MDT	Mesoscale Discussion	SPC	Phillips, Yuma	2 hr
Apr 12, 12:47 PM MDT	Tornado Watch	SPC	Cheyenne, Kiowa, Kit Carson, Logan, Phillips, Prowers and 3 more	7 hr
Apr 12, 4:02 PM MDT	Mesoscale Discussion	SPC	Cheyenne, Kit Carson, Phillips, Prowers, Sedgwick, Washington and 1 more	88 min

Nearby

Mesoscale Discussions in Colorado, 2012 Every mesoscale discussion in 2012

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.