Alert archive / Kansas / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 51, NWS Topeka, KS

May 20, 1998Jackson County, Kansas

NWS Topeka, KS issued this severe thunderstorm warning at May 20, 1998, 6:21 PM CDT for Jackson County, Kansas. It was in force for 49 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: May 20, 1998, 6:21 PM CDT (23:21 UTC)
Expired: May 20, 1998, 7:10 PM CDT
In force: 49 min
Issued by: NWS Topeka, KS
Area: Whole counties

County Jackson County, KS

The radar

The Topeka radar (KTWX), 60 km from the middle of the area, began a volume at 23:24 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.

What was reported inside it

Time	Report	Where	Remark
May 20, 6:40 PM CDT	Hail 0.75	Delia, KS

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 11.4 hours before the alert went out and 48 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: 3880 J/kg
Mixed-layer CIN: -84 J/kg
Mixed-layer LCL: 780 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 81 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.6

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Topeka, KS wrote its last area forecast discussion before this severe thunderstorm warning went out at May 20, 3:35 PM CDT, 2 hours 46 minutes earlier.

Area forecast discussion, May 20, 3:35 PM CDT, 2 hours 46 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
335 PM CDT WED MAY 20 1998

...MAIN FORECAST CONCERN CONTINUES TO BE...THUNDERSTORM CHANCES...

LAST NIGHTS MCS PUSHED THE FRONTAL BOUNDARY TO THE SOUTH...MORE IN
LINE WITH YESTERDAYS ETA.  LOOKS LIKE ANOTHER MCS SHOULD DEVELOP
TONIGHT AND PROPAGATE OUR DIRECTION...BUT STILL SHUNT OFF TO THE
EAST.  EXTREME NORTHEAST KANSAS STANDS THE BEST SHOT AT RAIN.  THAT
SHOULD SLIDE TO THE EAST BY NOON LEAVING SKIES PARTLY SUNNY.

THE QUESTION REMAINS...WHERE WILL THE FRONT BE LOCATED ??  THE MCS
SHOULD AGAIN ESTABLISH AN OUTFLOW THE HELP KEEP THE FRONT
SOUTH...BUT AT THE SAME TIME...AS THE WEST COAST SYSTEM DIG IN...THE
H500 RIDGE MAY AMPLIFY ENOUGH TO ALLOW THE FRONT TO DRIFT BACK A
LITTLE NORTH.  THIS SEEMS TO BE THE ETAS SOLUTION.

THIS SHOULD HELP FOCUS THE HEAVIER RAIN ON THURSDAY NIGHT WHERE
ETA/AVN BOTH SHOW VERY GOOD WARM AIR ADVECTION AND THETA-E
CONVERGENCE IN SOUTHERN/CENTRAL NEBRASKA AT 850 & 700.
THEREFORE...WILL ONLY HAVE 30-40 POPS NEEDED ALONG THE NEBRASKA
BORDER WITH LESSER AMOUNTS SOUTH.

BELIEVING THIS SCENARIO... WILL KEEP TEMPERATURES ON THE WARMER SIDE
OF GUIDANCE VALUES.

DLR

.TOP...NONE.

The office that day

Everything else NWS Topeka, KS issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 20, 6:14 PM CDT	Severe Thunderstorm Warning	TOP	Pottawatomie	46 min
May 20, 6:44 PM CDT	Tornado Warning	TOP	Pottawatomie, Riley	31 min

Nearby

Severe Thunderstorm Warnings in Kansas, 1998 Every severe thunderstorm warning in 1998

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.