Alert archive / Colorado / Mesoscale Discussions in 2012

Mesoscale Discussion 1091

June 6, 20128 counties in Colorado; 6 counties in Nebraska; Goshen County, Laramie County, Platte County, Wyoming

The Storm Prediction Center issued this mesoscale discussion at Jun 6, 2012, 8:37 PM MDT for 8 counties in Colorado; 6 counties in Nebraska; Goshen County, Laramie County, Platte County, Wyoming. It was in force for 23 min.

The area

The outline as issued.

The facts

Issued
Jun 6, 2012, 8:37 PM MDT (02:37 UTC)
Expired
Jun 6, 2012, 9:00 PM MDT
In force
23 min
Issued by
the Storm Prediction Center

Counties Adams County, CO, Arapahoe County, CO, Broomfield County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO, Morgan County, CO, Weld County, CO, Banner County, NE, Box Butte County, NE, Dawes County, NE, Kimball County, NE, Scotts Bluff County, NE, Sioux County, NE, Goshen County, WY, Laramie County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 73 km from the middle of the area, began a volume at 02:39 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, 2.6 hours before the alert went out and 122 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, Denver, CO at 00:00Z on 2012-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 859 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 2012-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 2 square meters per square second.1939Sfc1 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
859 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
2447 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
2 m²/s²
0-3 km storm-relative helicity
155 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.0

Open this sounding in Storm Lab

The text

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

837 
ACUS11 KWNS 070237
SWOMCD
SPC MCD 070237 
NEZ000-COZ000-WYZ000-070300-

MESOSCALE DISCUSSION 1091
NWS STORM PREDICTION CENTER NORMAN OK
0937 PM CDT WED JUN 06 2012

AREAS AFFECTED...SERN WY/NEB PANHANDLE/NERN CO

CONCERNING...TORNADO WATCH 361...

VALID 070237Z - 070300Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 361 CONTINUES.

SUMMARY...GREATEST SVR WEATHER THREAT IS EXPECTED TO REMAIN ACROSS
THE CO PORTION OF WW 361. LOCAL WFO TEMPORAL EXTENSION MAY BE NEEDED
BEYOND 03Z...ACCOUNTING FOR RESIDUAL INSTABILITY.

DISCUSSION...DESPITE WEAKER MIDLEVEL WINDS WITH SSEWD EXTENT INTO
ERN CO...A CONTINUED STRENGTHENING OF SELY LOW LEVEL WINDS INTO THE
CO FRONT RANGE /30-40 KT/ PER WIND PROFILERS/WSR-88DS HAS ENHANCED
BULK SHEAR TO 35-40 KT SUPPORTIVE OF UPDRAFT ROTATION.  THIS THREAT
IS EXPECTED TO REMAIN CONFINED TO CENTRAL CO...GENERALLY BETWEEN
DEN-COS WHERE FAVORABLE UPSLOPE FLOW REGIME WILL SUSTAIN PERSISTENT
COMPLEX OF STORMS IN THAT AREA.  THUS...UNTIL INSTABILITY IS
DEPLETED AND/OR SURFACE BASED INHIBITION STRENGTHENS...THEN A SMALL
SRN PORTION OF THIS WW MAY NEED TO BE LOCALLY EXTENDED IN TIME
BEYOND THE SCHEDULED EXPIRATION OF 03Z.

..PETERS.. 06/07/2012

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

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

LAT...LON   38890365 39060430 39120531 40340508 41040502 41370528
            42050518 42580447 42980397 42980298 40940306 39540339
            39540372 38890365

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 6, 6:47 PM MDTMesoscale DiscussionSPCAdams, Arapahoe, Broomfield, Denver, Douglas, Elbert and 4 more58 min
Jun 7, 10:59 AM MDTMesoscale DiscussionSPCLarimer, Weld91 min
Jun 7, 11:46 AM MDTTornado WatchSPCAdams, Arapahoe, Boulder, Broomfield, Denver, Douglas and 8 more10 hr
Jun 7, 1:59 PM MDTMesoscale DiscussionSPCAdams, Arapahoe, Broomfield, Denver, Morgan, Weld91 min
Jun 7, 5:52 PM MDTMesoscale DiscussionSPCAdams, Arapahoe, Boulder, Broomfield, Crowley, Denver and 11 more53 min

Nearby

Mesoscale Discussions in Colorado, 2012Mesoscale Discussions in Nebraska, 2012Mesoscale Discussions in Wyoming, 2012Every 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.