Alert archive / Kansas / Mesoscale Discussions in 2003

Mesoscale Discussion 646

April 30, 200317 counties in Kansas

The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2003, 6:29 PM CDT for 17 counties in Kansas. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued: Apr 30, 2003, 6:29 PM CDT (23:29 UTC)
Expired: Apr 30, 2003, 8:00 PM CDT
In force: 91 min
Issued by: the Storm Prediction Center

Counties Butler County, KS, Chase County, KS, Coffey County, KS, Cowley County, KS, Elk County, KS, Franklin County, KS, Greenwood County, KS, Jackson County, KS, Lyon County, KS, Morris County, KS, Osage County, KS, Pottawatomie County, KS, Shawnee County, KS, Sumner County, KS, Wabaunsee County, KS, Wilson County, KS, Woodson County, KS

The radar

The Wichita radar (KICT), 90 km from the middle of the area, began a volume at 23:28 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 191Apr 30, 7:30 PM CDT

The nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 11.5 hours before the alert went out and 137 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: 758 J/kg
Mixed-layer CIN: -361 J/kg
Mixed-layer LCL: 980 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 284 m²/s²
0-3 km storm-relative helicity: 293 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.

624 
ACUS11 KWNS 302330
SWOMCD
SPC MCD 302329 
KSZ000-010100-

MESOSCALE DISCUSSION 0646
NWS STORM PREDICTION CENTER NORMAN OK
0629 PM CDT WED APR 30 2003

AREAS AFFECTED...ERN KS

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 302329Z - 010100Z

TSTMS MAY DEVELOP ALONG COLD FRONT WITHIN THE NEXT 1 TO 2 HOURS. WW
MAY BE REQUIRED. 

LATEST VISIBLE SATELLITE DATA INDICATE SURFACE COLD FRONT EXTENDING
FROM MARSHALL COUNTY SWWD TO SUMNER COUNTY SLOWLY MOVING EWD.
TEMPERATURES IN THE 80S AND DEWPOINTS IN THE LOWER TO MID 60S HAVE
CONTRIBUTED TO A MODERATELY TO STRONGLY UNSTABLE AIRMASS WITH
MLCAPES OF 2000-3000 J/KG. TSTMS MAY INITIATE WITHIN THE NEXT COUPLE
OF HOURS AS COLD FRONT INTERACTS WITH HORIZONTAL ROLLS/CLOUD STREETS
EVIDENT  IN THE VISIBLE SATELLITE IMAGERY. LOW-LEVEL CONVERGENCE
WILL BE FURTHER ENHANCED AS FORCING FOR LARGE-SCALE ASCENT
ASSOCIATED WITH MID-LEVEL SHORTWAVE TROUGH...CURRENTLY OVER S-CNTRL
NEB/N-CNTRL KS...CONTINUES TO OVERSPREAD THE WARM SECTOR.

DEEP-LAYER SHEAR ON THE ORDER OF 30-40KTS SUGGESTS THE POTENTIAL FOR
ORGANIZED TSTMS/ROTATING UPDRAFTS GIVEN THE DEGREE OF INSTABILITY.
LINEAR FORCING ALONG COLD FRONT AND SLIGHT VEERING NOTED IN THE
BOUNDARY-LAYER WINDS AHEAD OF THE COLD FRONT SUGGESTS THAT THE
PRIMARY SEVERE WEATHER THREATS WILL BE DAMAGING WINDS AND LARGE
HAIL. 

..MEAD.. 04/30/2003

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

ATTN...WFO...EAX...TOP...ICT...

37089761 37339778 37839714 39619627 39689563 38549524
37899547 37509577 37129645

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 29, 7:56 PM CDT	Mesoscale Discussion	SPC	Clay, Cloud, Decatur, Graham, Jewell, Mitchell and 10 more	2 hr
Apr 29, 8:45 PM CDT	Severe Thunderstorm Watch	SPC	Brown, Cheyenne, Clay, Cloud, Decatur, Dickinson and 29 more	5 hr
Apr 29, 10:29 PM CDT	Mesoscale Discussion	SPC	Brown, Cheyenne, Clay, Cloud, Decatur, Dickinson and 28 more	2 hr
Apr 30, 1:22 AM CDT	Mesoscale Discussion	SPC	Decatur, Norton, Phillips, Rawlins	113 min
Apr 30, 1:49 AM CDT	Mesoscale Discussion	SPC	Decatur, Norton, Phillips, Rawlins	116 min
Apr 30, 2:49 PM CDT	Mesoscale Discussion	SPC	Atchison, Brown, Clay, Dickinson, Doniphan, Geary and 13 more	116 min
Apr 30, 3:28 PM CDT	Mesoscale Discussion	SPC	Greeley, Wallace, Wichita	92 min
Apr 30, 5:15 PM CDT	Tornado Watch	SPC	Doniphan, Johnson, Leavenworth, Wyandotte	6 hr

Nearby

Mesoscale Discussions in Kansas, 2003 Every 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; radar from the NEXRAD Level II archive.