Alert archive / Colorado / Mesoscale Discussions in 2012

Mesoscale Discussion 1096

June 7, 201217 counties in Colorado; 8 counties in Nebraska; 6 counties in Wyoming

The Storm Prediction Center issued this mesoscale discussion at Jun 7, 2012, 5:52 PM MDT for 17 counties in Colorado; 8 counties in Nebraska; 6 counties in Wyoming. It was in force for 53 min.

The area

The outline as issued.

The facts

Issued
Jun 7, 2012, 5:52 PM MDT (23:52 UTC)
Expired
Jun 7, 2012, 6:45 PM MDT
In force
53 min
Issued by
the Storm Prediction Center
All 31 counties

Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Crowley County, CO, Denver County, CO, Douglas County, CO, El Paso County, CO, Elbert County, CO, Gilpin County, CO, Jefferson County, CO, Larimer County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Washington County, CO, Weld County, CO, Banner County, NE, Box Butte County, NE, Cheyenne County, NE, Dawes County, NE, Kimball County, NE, Morrill County, NE, Scotts Bluff County, NE, Sioux County, NE, Albany County, WY, Converse County, WY, Goshen County, WY, Laramie County, WY, Niobrara County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 55 km from the middle of the area, began a volume at 23:54 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, 11.9 hours before the alert went out and 147 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 12:00Z on 2012-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1398 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 12:00Z on 2012-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 square meters per square second.193958Sfc1 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
1398 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
671 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
105 m²/s²
Significant tornado parameter
0.4
Supercell composite
1.8

Open this sounding in Storm Lab

The text

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

688 
ACUS11 KWNS 072353
SWOMCD
SPC MCD 072352
NEZ000-COZ000-SDZ000-WYZ000-080045-

MESOSCALE DISCUSSION 1096
NWS STORM PREDICTION CENTER NORMAN OK
0652 PM CDT THU JUN 07 2012

AREAS AFFECTED...SE AND E-CENTRAL WY/NEB PANHANDLE/N-CENTRAL AND NE
CO

CONCERNING...TORNADO WATCH 362...

VALID 072352Z - 080045Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 362 CONTINUES.

SUMMARY...THE POTENTIAL FOR SUPERCELLS WITH TORNADOES AND VERY LARGE
HAIL /EXCEEDING 2 INCH DIAMETER/ WILL PERSIST INTO THE EVENING
ACROSS THE CENTRAL HIGH PLAINS REGION FROM SERN WY AND NEB PANHANDLE
SWD THROUGH NORTH CENTRAL/NERN TO PARTS OF EAST CENTRAL CO.

GIVEN POTENTIAL FOR STRONGER STORMS TO AFFECT LINCOLN COUNTY
CO...THIS COUNTY HAS BEEN ADDED TO WW 362 BY WFO DENVER/BOULDER.

DISCUSSION...TSTM DEVELOPMENT CONTINUES ACROSS WW 362 PER REGIONAL
RADAR IMAGERY.  TRENDS IN OBJECTIVE ANALYSES SHOW A MODERATE-VERY
UNSTABLE AIR MASS AND STRONG BULK SHEAR /35-45 KT PERPENDICULAR TO
THE GENERAL N-S INITIATING BOUNDARIES/ INDICATES AN ENVIRONMENT VERY
CONDUCIVE FOR SUPERCELL DEVELOPMENT...INCLUDING SPLITTING STORMS.
IN ADDITION TO STORMS FORMING ALONG THE FRONT RANGE FROM CO NWD INTO
SERN WY...STORMS HAVE ALSO FORMED ALONG THE ERN PERIPHERY OF THE DEN
CYCLONE.  THE SPECIAL DEN SOUNDING AT 19Z MODIFIED FOR ADDITIONAL
SURFACE HEATING AND GREATER MOIST INFLOW /81 F/54 F/ OVER THE LOWER
ELEVATIONS REMOVED THE REMAINING CAP AND RESULTED IN VERY STRONG
INSTABILITY /MLCAPE 3000+ J PER KG/ FOR STORM DEVELOPMENT OVER THE
SRN EXTENT OF WW 362.  LOCAL SPC HAIL MODEL SUGGESTS DIAMETERS CAN
EXCEED 2 INCH PER THE MODIFIED DEN SOUNDING...WITH THIS VERIFIED
BETWEEN 2330-2340Z IN ARAPAHOE COUNTY CO /2.5 INCH/ AND MORGAN
COUNTY CO /2.75 INCH/.

EFFECTIVE SRH PER OBJECTIVE ANALYSES INDICATED VALUES OF 100-200
M2/S2 EXTENDING FROM ERN WY SSEWD THROUGH ERN CO WITHIN THE CORRIDOR
OF ONGOING STORMS.  THESE VALUES SHOULD INCREASE THIS EVENING AS
SSELY LOW LEVEL WINDS STRENGTHEN INTO ERN CO FURTHER ENHANCING THE
TORNADO POTENTIAL.

FARTHER S...STORM DEVELOPMENT IS EXPECTED TO REMAIN MORE ISOLATED
OVER SERN CO AS THIS REGION REMAINS SOMEWHAT REMOVED FROM STRONGER
FORCING FOR ASCENT WITH THE SHORTWAVE TROUGHS SUPPORTING THE
ACTIVITY OVER WW 362.  HOWEVER...ANY LEFT SPLIT STORMS WILL BE
CAPABLE OF MOVING INTO THE SRN EXTENT OF WW 362.

..PETERS.. 06/07/2012

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

ATTN...WFO...LBF...UNR...GLD...PUB...BOU...CYS...

LAT...LON   43460603 43490409 43010401 42990278 40960254 39470276
            38440316 38020357 38110439 38590465 39020455 39110536
            39980569 40830609 41210631 41500609 43460603

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 6, 8:37 PM MDTMesoscale DiscussionSPCAdams, Arapahoe, Broomfield, Denver, Douglas, Elbert and 2 more23 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

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.