Alert archive / Colorado / Mesoscale Discussions in 2003

Mesoscale Discussion 644

April 30, 20038 counties in Colorado; Greeley County, Wallace County, Wichita County, Kansas

The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2003, 2:28 PM MDT for 8 counties in Colorado; Greeley County, Wallace County, Wichita County, Kansas. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
Apr 30, 2003, 2:28 PM MDT (20:28 UTC)
Expired
Apr 30, 2003, 4:00 PM MDT
In force
92 min
Issued by
the Storm Prediction Center

Counties Adams County, CO, Arapahoe County, CO, Broomfield County, CO, Cheyenne County, CO, Denver County, CO, Elbert County, CO, Larimer County, CO, Lincoln County, CO, Greeley County, KS, Wallace County, KS, Wichita County, KS

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 8.5 hours before the alert went out and 58 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 2003-04-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 446 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 2003-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -12 square meters per square second.19395878Sfc1 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
446 J/kg
Mixed-layer CIN
-79 J/kg
Mixed-layer LCL
984 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
-12 m²/s²
0-3 km storm-relative helicity
-6 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.

101 
ACUS11 KWNS 302028
SWOMCD
SPC MCD 302028 
KSZ000-COZ000-302200-

MESOSCALE DISCUSSION 0644
NWS STORM PREDICTION CENTER NORMAN OK
0328 PM CDT WED APR 30 2003

AREAS AFFECTED...ERN CO AND WRN KS

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 302028Z - 302200Z

ISOLATED SUPERCELLS WILL REMAIN POSSIBLE THROUGH THE AFTERNOON OVER
ERN CO/FAR WRN KS ALONG A SWD MOVING BOUNDARY...WITH ADDITIONAL
STORMS ALSO LIKELY OVER THE CENTRAL HIGH PLAINS OF NRN/ERN CO. 
ISOLATED COVERAGE WILL PREVENT WW ISSUANCE ATTM.

20Z SURFACE ANALYSIS SHOWS A BOUNDARY IN LEE OF THE ROCKIES OVER NRN
CO WITH THE BOUNDARY THEN EXTENDING ESEWD FROM DOUGLAS COUNTY CO TO
CHEYENNE COUNTY CO AND INTO WRN KS.  OBJECTIVE ANALYSES INDICATE A
MARGINALLY UNSTABLE AIR MASS ALONG THIS BOUNDARY...WITH STRONG DEEP
LAYER SHEAR SUPPORTIVE OF SUPERCELLS.  THUNDERSTORMS WITH ISOLATED
SUPERCELLS WILL CONTINUE TO DEVELOP THIS AFTERNOON EAST OF THE
HIGHER TERRAIN OVER NRN CO AND ESEWD ALONG A SURFACE BOUNDARY OVER
EAST CENTRAL CO INTO WEST CENTRAL KS...BUT SHOULD REMAIN ISOLATED IN
COVERAGE DUE TO THE MARGINAL INSTABILITY.  

..PETERS.. 04/30/2003

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

ATTN...WFO...GLD...PUB...BOU...

39000200 38930122 38380120 38470282 38810449 40000526
40830555 40750491 39340363

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 29, 7:45 PM MDTSevere Thunderstorm WatchSPCCheyenne, Elbert, El Paso, Kit Carson, Lincoln, Washington and 1 more5 hr
Apr 29, 9:29 PM MDTMesoscale DiscussionSPCCheyenne, Elbert, El Paso, Kit Carson, Lincoln, Phillips and 1 more2 hr
Apr 29, 6:56 PM MDTMesoscale DiscussionSPCClay, Cloud, Decatur, Graham, Jewell, Mitchell and 10 more2 hr
Apr 30, 12:22 AM MDTMesoscale DiscussionSPCDecatur, Norton, Phillips, Rawlins113 min
Apr 30, 12:49 AM MDTMesoscale DiscussionSPCDecatur, Norton, Phillips, Rawlins116 min
Apr 30, 1:49 PM MDTMesoscale DiscussionSPCAtchison, Brown, Clay, Dickinson, Doniphan, Geary and 13 more116 min
Apr 30, 4:15 PM MDTTornado WatchSPCDoniphan, Johnson, Leavenworth, Wyandotte6 hr
Apr 30, 5:29 PM MDTMesoscale DiscussionSPCButler, Chase, Coffey, Cowley, Elk, Franklin and 11 more91 min

Nearby

Mesoscale Discussions in Colorado, 2003Mesoscale Discussions in Kansas, 2003Every mesoscale discussion in 2003

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.