Alert archive / Kansas / Mesoscale Discussions in 2003

Mesoscale Discussion 621

April 29, 200317 counties in Kansas; 6 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Apr 29, 2003, 2:19 PM CDT for 17 counties in Kansas; 6 counties in Nebraska. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued
Apr 29, 2003, 2:19 PM CDT (19:19 UTC)
Expired
Apr 29, 2003, 4:15 PM CDT
In force
116 min
Issued by
the Storm Prediction Center
All 23 counties

Cloud County, KS, Ellis County, KS, Ellsworth County, KS, Graham County, KS, Jewell County, KS, Lincoln County, KS, Mitchell County, KS, Norton County, KS, Osborne County, KS, Ottawa County, KS, Phillips County, KS, Republic County, KS, Rooks County, KS, Russell County, KS, Saline County, KS, Smith County, KS, Trego County, KS, Franklin County, NE, Furnas County, NE, Harlan County, NE, Nuckolls County, NE, Thayer County, NE, Webster County, NE

The radar

The Grand Island radar (KUEX), 101 km from the middle of the area, began a volume at 19:21 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.

The nearest sounding before it

Dodge City, (KDDC), launched 12:00Z, 7.3 hours before the alert went out and 214 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, Dodge City, at 12:00Z on 2003-04-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 20 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Dodge City, at 12:00Z on 2003-04-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 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
20 J/kg
Mixed-layer CIN
-565 J/kg
Mixed-layer LCL
1571 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
61 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.

930 
ACUS11 KWNS 291920
SWOMCD
SPC MCD 291919 
KSZ000-NEZ000-292115-

MESOSCALE DISCUSSION 0621
NWS STORM PREDICTION CENTER NORMAN OK
0219 PM CDT TUE APR 29 2003

AREAS AFFECTED...SRN-SERN NE

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 291919Z - 292115Z

SCATTERED ELEVATED THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS
SCNTRL-SERN NE OVER THE NEXT FEW HOURS. ADDITIONAL STORMS WILL
LIKELY INITIATE ACROSS NRN-CNTRL KS LATER THIS AFTERNOON.
INITIALLY...LARGE HAIL WILL BE THE PRIMARY THREAT WITH THE ELEVATED
CONVECTION NORTH OF THE FRONT. ADDITIONAL STORMS INITIATING ACROSS
CNTRL AND NRN KS WILL HAVE A POTENTIAL FOR HAIL AND WIND. ISOLATED
TORNADOES WILL ALSO BE POSSIBLE PARTICULARLY WITH SUPERCELLS. A WW
WILL LIKELY BE NECESSARY WITHIN THE NEXT FEW HOURS.

SLY FLOW SOUTH OF A WARM FRONT ACROSS NRN KS HAD BROUGHT UPPER 50 TO
LOWER 60 F SFC DEWPOINTS INTO NRN KS AND SRN NE. SFC TEMPS IN THE
70S HAD RESULTING IN MLCAPE VALUES OF 1500-2000 J/KG IN THIS REGION.
VIS SATELLITE SHOWED CU FIELD INCREASING IN SIZE ACROSS NRN KS.
STORMS SHOULD INITIATE IN THIS AREA NEAR THE WARM FRONT AND MOVE EWD
LATER THIS AFTERNOON. AS STORMS INTERACT WITH MODERATE TO STRONG
DEEP LAYER SHEAR WITH 0-6 KM SHEAR VALUES OF 40 TO 50 KNOTS...A FEW
SUPERCELLS MAY DEVELOP. INITIALLY...THE SUPERCELLS WILL BE CAPABLE
OF LARGE HAIL AND WIND DAMAGE. AS THE LOW-LEVEL JET STRENGTHENS LATE
THIS AFTERNOON...ISOLATED TORNADOES WILL BE POSSIBLE MAINLY IN THE
VICINITY AND S OF THE WARM FRONT. OTHER ELEVATED CELLS N OF THE
FRONT WILL BE CAPABLE LARGE HAIL. A WW WILL LIKELY BECOME NECESSARY
LATER THIS AFTERNOON.

..BROYLES.. 04/29/2003

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

ATTN...WFO...OAX...TOP...ICT...GID...DDC...GLD...

38619927 38830018 39370037 40250024 40499938 40459797
40349736 39779716 39089724 38799745 38629816

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 28, 7:10 PM CDTMesoscale DiscussionSPCAllen, Anderson, Bourbon, Butler, Chase, Chautauqua and 12 more2 hr
Apr 28, 11:50 PM CDTMesoscale DiscussionSPCCheyenne, Rawlins2 hr
Apr 29, 2:15 AM CDTMesoscale DiscussionSPCDecatur, Jewell, Norton, Phillips, Rawlins, Republic and 2 more3 hr
Apr 29, 3:40 PM CDTTornado WatchSPCClay, Cloud, Decatur, Dickinson, Ellis, Ellsworth and 19 more5 hr
Apr 29, 4:10 PM CDTSevere Thunderstorm WatchSPCCheyenne, Logan, Rawlins, Scott, Sherman, Thomas and 1 more6 hr
Apr 29, 5:52 PM CDTMesoscale DiscussionSPCClay, Cloud, Decatur, Dickinson, Ellis, Ellsworth and 19 more53 min
Apr 29, 6:16 PM CDTMesoscale DiscussionSPCCheyenne, Logan, Rawlins, Scott, Sherman, Thomas and 2 more119 min
Apr 29, 3:47 PM CDTMesoscale DiscussionSPCKimball118 min

Nearby

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