Alert archive / Colorado / Mesoscale Discussions in 2011

Mesoscale Discussion 2285

November 2, 201112 counties in Colorado; 11 counties in Kansas; Furnas County, Red Willow County, Nebraska

The Storm Prediction Center issued this mesoscale discussion at Nov 2, 2011, 6:58 AM MDT for 12 counties in Colorado; 11 counties in Kansas; Furnas County, Red Willow County, Nebraska. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Nov 2, 2011, 6:58 AM MDT (12:58 UTC)
Expired: Nov 2, 2011, 12:00 PM MDT
In force: 5 hr
Issued by: the Storm Prediction Center

All 25 counties

Bent County, CO, Cheyenne County, CO, Crowley County, CO, Custer County, CO, Huerfano County, CO, Kiowa County, CO, Kit Carson County, CO, Las Animas County, CO, Lincoln County, CO, Otero County, CO, Prowers County, CO, Pueblo County, CO, Decatur County, KS, Greeley County, KS, Hamilton County, KS, Logan County, KS, Norton County, KS, Rawlins County, KS, Sheridan County, KS, Sherman County, KS, Thomas County, KS, Wallace County, KS, Wichita County, KS, Furnas County, NE, Red Willow County, NE

The radar

The Goodland radar (KGLD), 119 km from the middle of the area, began a volume at 13:00 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 12:00Z, 1.0 hours before the alert went out and 136 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: 497 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 107 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.

091 
ACUS11 KWNS 021258
SWOMCD
SPC MCD 021258 
KSZ000-NEZ000-COZ000-021800-

MESOSCALE DISCUSSION 2285
NWS STORM PREDICTION CENTER NORMAN OK
0758 AM CDT WED NOV 02 2011

AREAS AFFECTED...PORTIONS S-CENTRAL THROUGH E-CENTRAL CO...NWRN
KS...SWRN NEB.

CONCERNING...BLIZZARD 

VALID 021258Z - 021800Z

THROUGH 15Z...THREAT EXISTS FOR MDT-HEAVY SNOW ACCOMPANIED BY OCNL
BLIZZARD CONDITIONS...SHIFTING SEWD ACROSS SWATH OF CENTRAL HIGH
PLAINS FROM TAD/PUB AREAS NEWD OVER LHX/LAA AREAS TO NEAR GLD...MCK
AND PERHAPS HLC.  1-2 INCH/HOUR RATES ARE EXPECTED WITH
ISOLATED/LOCALIZED CONVECTIVE ENHANCEMENT ACCOMPANIED BY LTG. 
UPSLOPE/OROGRAPHIC ASCENT ALSO WILL CONTRIBUTE TO ENHANCED SNOW OVER
AREAS W OF I-25 SWD TO NEAR NM BORDER...WITH SOME 2-3 INCH/HOUR
RATES REACHING ELEVATIONS BELOW 8000 FT MSL.

MULTITUDE OF FORCINGS FOR DEEP-LAYER ASCENT AFFECTING DENDRITIC
GROWTH ZONES ARE EVIDENT AHEAD OF STG CENTRAL ROCKIES SHORTWAVE
TROUGH -- ANCHORED BY 500-MB LOW NOW EVIDENT IN MOISTURE CHANNEL
IMAGERY OVER SW CO.  LOW AND TROUGH WILL MOVE ESEWD THROUGH 18Z
ACROSS SRN CO TO NERN NM AND SWRN KS.  LARGE-SCALE DCVA WILL BE
JUXTAPOSED WITH MIDLEVEL FRONTOGENETIC LIFT AND PARALLEL/SW-NE
ALIGNED BANDS OF CONDITIONAL SYMMETRIC INSTABILITY TO SUPPORT
SLANTWISE CONVECTION...INITIALLY OVER CO THEN EWD ACROSS KS BORDER
BY 15Z.  MEANWHILE PROBABILITY FOR UPRIGHT CONVECTION AND THUNDER
EXISTS BOTH NEAR COLD-CORE REGION OF CYCLONE...AS ALREADY OBSERVED
IN S-CENTRAL CO...AND INCREASING WITH EWD EXTENT ACROSS ERN CO/WRN
KS IN PROXIMITY TO ELEVATED CONVEYOR OF MOISTENING.  MUCAPE 100-350
J/KG IS POSSIBLE...ROOTED BETWEEN 500-600 MB.  COMBINATION OF
COLUMNAR DYNAMIC COOLING AND POSTFRONTAL LOW-LEVEL CAA WILL SHUNT
BOUNDARY-LAYER FREEZING LINE SWD FROM S-CENTRAL/SWRN NEB INTO
W-CENTRAL KS ALSO...SUPPORTING POTENTIAL FOR SNOW TO SPREAD NEWD
OVER S-CENTRAL NEB BY 18Z.

..EDWARDS.. 11/02/2011

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

ATTN...WFO...GID...LBF...DDC...GLD...PUB...BOU...

LAT...LON   38520487 39250386 39740309 39570208 40290065 40439997
            39979957 39409986 38390118 37660230 37330305 37120365
            37120450 37490520 38380580 38520487

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Nov 1, 7:13 PM MDT	Mesoscale Discussion	SPC	Adams, Arapahoe, Boulder, Broomfield, Chaffee, Clear Creek and 22 more	5 hr
Nov 2, 3:54 AM MDT	Mesoscale Discussion	SPC	Bent, Cheyenne, Crowley, Custer, Huerfano, Kiowa and 6 more	5 hr

Nearby

Mesoscale Discussions in Colorado, 2011 Mesoscale Discussions in Kansas, 2011 Mesoscale Discussions in Nebraska, 2011 Every mesoscale discussion in 2011

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.