Alert archive / Colorado / Mesoscale Discussions in 2016

Mesoscale Discussion 792

May 30, 201614 counties in Colorado; Cheyenne County, Rawlins County, Sherman County, Kansas; 11 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at May 30, 2016, 1:56 PM MDT for 14 counties in Colorado; Cheyenne County, Rawlins County, Sherman County, Kansas; 11 counties in Nebraska. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued: May 30, 2016, 1:56 PM MDT (19:56 UTC)
Expired: May 30, 2016, 3:00 PM MDT
In force: 64 min
Issued by: the Storm Prediction Center
Chance of a watch: 80%

All 28 counties

Adams County, CO, Arapahoe County, CO, Cheyenne County, CO, Denver County, CO, Elbert County, CO, Kit Carson County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO, Yuma County, CO, Cheyenne County, KS, Rawlins County, KS, Sherman County, KS, Chase County, NE, Cheyenne County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Hayes County, NE, Hitchcock County, NE, Keith County, NE, Lincoln County, NE, Perkins County, NE, Red Willow County, NE

The radar

The Goodland radar (KGLD), 110 km from the middle of the area, began a volume at 20:02 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 232May 30, 2:20 PM MDT

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 7.9 hours before the alert went out and 64 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: 2218 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 36 m²/s²
0-3 km storm-relative helicity: 54 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

929 
ACUS11 KWNS 301956
SWOMCD
SPC MCD 301956 
NEZ000-KSZ000-COZ000-WYZ000-302100-

MESOSCALE DISCUSSION 0792
NWS STORM PREDICTION CENTER NORMAN OK
0256 PM CDT MON MAY 30 2016

AREAS AFFECTED...NE CO...SW NEB...FAR NW KS

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 301956Z - 302100Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...TSTM COVERAGE IS EXPECTED TO GRADUALLY INCREASE ACROSS NE
CO AND SW NEB. AIRMASS IS SUPPORTIVE OF SVR TSTMS AND A WW WILL
LIKELY BE NEEDED TO COVER THE THREAT.

DISCUSSION...LARGE-SCALE FORCING FOR ASCENT WILL CONTINUE TO
INCREASE ACROSS THE REGION AS A SHORTWAVE TROUGH NOW NEAR THE UT/CO
BORDER CONTINUES EWD. MESOSCALE FORCING FOR ASCENT ALSO EXISTS WITH
WEAK UPSLOPE FLOW CONTRIBUTING TO CONVERGENCE IN THE FOOTHILLS AND A
WEAK DRYLINE MOVING INTO NE CO. ALL OF THESE FACTORS ARE EXPECTED TO
CONTRIBUTE TO INCREASED TSTM COVERAGE DURING THE NEXT FEW HOURS. 

AIRMASS IN THE REGION IS CHARACTERIZED BY TEMPERATURES IN THE UPPER
70S AND LOW 80S AND DEWPOINTS IN THE MID 40S TO LOW 50S. STEEP
MID-LEVEL LAPSE RATES AMIDST THESE SURFACE CONDITIONS ARE
CONTRIBUTING TO MLCAPE AROUND 1000-1500 J/KG. 0-6 KM BULK SHEAR
SAMPLED BY THE CYS AND FTG RADARS IS AROUND 35 KT...WHICH SHOULD BE
SUFFICIENT FOR MODEST UPDRAFT ORGANIZATION. THE PRIMARY SEVERE
THREATS WILL BE DAMAGING WIND GUSTS AND HAIL BUT RECENT MESOANALYSIS
SUGGESTS ENOUGH SURFACE VORTICITY EXISTS FOR A BRIEF TORNADO. A WW
WILL LIKELY BE NEEDED TO COVER THE SVR THREAT.

..MOSIER/CORFIDI.. 05/30/2016

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

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

LAT...LON   41460056 40460028 39710075 39240129 38700238 38740402
            38980473 39570494 40450477 40980422 41590213 41460056

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 30, 2:19 PM MDT	Severe Thunderstorm Watch	SPC	Cheyenne, Elbert, Kiowa, Kit Carson, Lincoln, Logan and 5 more	7 hr
May 30, 12:16 PM MDT	Mesoscale Discussion	SPC	Anderson, Atchison, Bourbon, Brown, Cherokee, Crawford and 9 more	119 min
May 30, 1:16 PM MDT	Mesoscale Discussion	SPC	Blaine, Brown, Cherry, Grant, Hooker, Keya Paha and 2 more	59 min
May 30, 4:14 PM MDT	Mesoscale Discussion	SPC	Burt, Butler, Cass, Colfax, Cuming, Dakota and 13 more	91 min

Nearby

Mesoscale Discussions in Colorado, 2016 Mesoscale Discussions in Nebraska, 2016 Mesoscale Discussions in Kansas, 2016 Every mesoscale discussion in 2016

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.