Alert archive / Colorado / Mesoscale Discussions in 2014

Mesoscale Discussion 656

May 22, 201412 counties in Colorado; 4 counties in Wyoming

The Storm Prediction Center issued this mesoscale discussion at May 22, 2014, 12:07 PM MDT for 12 counties in Colorado; 4 counties in Wyoming. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued: May 22, 2014, 12:07 PM MDT (18:07 UTC)
Expired: May 22, 2014, 1:30 PM MDT
In force: 83 min
Issued by: the Storm Prediction Center
Chance of a watch: 60%

Counties Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO, Gilpin County, CO, Jefferson County, CO, Larimer County, CO, Morgan County, CO, Weld County, CO, Albany County, WY, Goshen County, WY, Laramie County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 49 km from the middle of the area, began a volume at 18:10 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.

Severe Thunderstorm Watch 175May 22, 12:35 PM MDT

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 6.1 hours before the alert went out and 197 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: 49 J/kg
Mixed-layer CIN: -195 J/kg
Mixed-layer LCL: 772 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: -16 m²/s²
0-3 km storm-relative helicity: 75 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.

568 
ACUS11 KWNS 221807
SWOMCD
SPC MCD 221807 
COZ000-NEZ000-WYZ000-221930-

MESOSCALE DISCUSSION 0656
NWS STORM PREDICTION CENTER NORMAN OK
0107 PM CDT THU MAY 22 2014

AREAS AFFECTED...CO FRONT RANGE AND ADJACENT HIGH PLAINS / SERN WY

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 221807Z - 221930Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...WIDELY SCATTERED STRONG TO LOCALLY SEVERE MULTICELLULAR
STORMS WILL POSE AN ISOLATED WIND/HAIL THREAT THIS AFTERNOON AND
EARLY THIS EVENING.

DISCUSSION...SUBJECTIVE SURFACE MESOANALYSIS SHOWS ELY UPSLOPE FLOW
INTO THE CNTRL HIGH PLAINS --ALBEIT MORE RELAXED THAN YESTERDAY--
AND THE DEVELOPMENT OF A DCVZ.  SURFACE OBSERVATIONS AT 18Z SHOW
DEWPOINTS HOLDING IN THE UPPER 40S TO LOWER 50S AND THE BACKED
LOW-LEVEL FLOW WILL PROBABLY OFFSET APPRECIABLE DECLINE/MIXING OF
DEWPOINTS INTO THE 40S.  STRONG SURFACE HEATING ON THE E SLOPES OF
THE FRONT RANGE AND HIGHER TERRAIN OF SERN WY HAS FOSTERED SCATTERED
CONVECTIVE DEVELOPMENT THUS FAR.  THE BOUNDARY LAYER E OF THE MTNS
CONTINUES TO HEAT AND DESTABILIZE AND THIS IS RESULTING IN
INCREASING THE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS. 
MID-LEVEL FLOW IS MODEST /GENERALLY AOB 15 KT PER MODEL FORECAST
SOUNDINGS/ UNDERNEATH A MID-LEVEL RIDGE AXIS...BUT MODERATE
INSTABILITY PROMOTE THE STRONGER STORMS TO POSE AT LEAST AN ISOLD
WIND/HAIL THREAT DURING THE 19Z-01Z TIMEFRAME.

..SMITH/HART.. 05/22/2014

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

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

LAT...LON   39440558 41060573 41670650 42450656 42950571 42710455
            41400394 39740365 39110418 39020510 39440558

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 22, 11:32 AM MDT	Mesoscale Discussion	SPC	Crowley, Huerfano, Las Animas, Otero, Pueblo	88 min
May 22, 11:53 AM MDT	Severe Thunderstorm Watch	SPC	Baca, Bent, Crowley, El Paso, Huerfano, Kiowa and 4 more	7 hr
May 22, 12:34 PM MDT	Severe Thunderstorm Watch	SPC	Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas and 6 more	6 hr
May 22, 4:55 PM MDT	Mesoscale Discussion	SPC	Baca, Bent, Prowers	65 min
May 22, 5:50 PM MDT	Mesoscale Discussion	SPC	Kit Carson, Yuma	55 min

Nearby

Mesoscale Discussions in Colorado, 2014 Mesoscale Discussions in Wyoming, 2014 Every mesoscale discussion in 2014

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.