Alert archive / Kansas / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 158, NWS Topeka, KS

August 9, 2020Coffey County, Kansas

NWS Topeka, KS issued this severe thunderstorm warning at Aug 9, 2020, 6:45 PM CDT for Coffey County, Kansas. It was in force for 45 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 9, 2020, 6:45 PM CDT (23:45 UTC)
Expired: Aug 9, 2020, 7:30 PM CDT
In force: 45 min
Issued by: NWS Topeka, KS
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Coffey County, KS

The radar

The Topeka radar (KTWX), 95 km from the middle of the area, began a volume at 23:46 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 nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 11.8 hours before the alert went out and 85 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: 505 J/kg
Mixed-layer CIN: -362 J/kg
Mixed-layer LCL: 1569 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 310 m²/s²
0-3 km storm-relative helicity: 180 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.2

Open this sounding in Storm Lab

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 Aug 9, 6:33 PM CDT, 12 minutes earlier.

Area forecast discussion, Aug 9, 6:33 PM CDT, 12 minutes before

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Hazardous weather outlook, Aug 9, 3:29 PM CDT, 3 hours 16 minutes before

Hazardous Weather Outlook
National Weather Service Topeka KS
329 PM CDT Sun Aug 9 2020

KSZ008>012-020>024-026-034>040-054>056-058-059-102030-
Republic-Washington-Marshall-Nemaha-Brown-Cloud-Clay-Riley-
Pottawatomie-Jackson-Jefferson-Ottawa-Dickinson-Geary-Morris-
Wabaunsee-Shawnee-Douglas-Lyon-Osage-Franklin-Coffey-Anderson-
329 PM CDT Sun Aug 9 2020

This hazardous weather outlook is for east central...north
central and northeast Kansas.

.DAY ONE...This Afternoon and tonight.

A few thunderstorms are possible through the late afternoon hours
along and southeast of I-35. A few thunderstorms may redevelop
late Tonight across north central and northeast Kansas.

Heat indices may increase to the 100 to 106 degree range late
this afternoon. A Heat Advisory remains in effect for portions of
northeast, east central, and north central Kansas.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

A few strong to severe storms may develop across the area Monday
afternoon and evening along an approaching cold front. Heavy
rainfall may also cause localized flooding across central and east
central Kansas.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed through tonight.

&&

More detailed information can be accessed at...
http://www.weather.gov/top/sitrep

In the hours before

Local storm report, Aug 9, 2:32 PM CDT, 4 hours 13 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
232 PM CDT SUN AUG 9 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0215 PM     HEAVY RAIN       3 W LATIMER             38.74N 96.91W
08/09/2020  M5.60 INCH       MORRIS             KS   TRAINED SPOTTER

            STORM TOTAL SINCE 7:00AM. FELL IN A VERY
            NARROW BAND WITH ONLY AN INCH OR TWO OF RAIN
            RECORDED A FEW MILES TO THE NORTH OR SOUTH.
            STREAMS AND PONDS FULL, BUT NO OTHER
            FLOODING NOTED.

&&

Special weather statement, Aug 9, 5:29 PM CDT, 1 hour 16 minutes before

Special Weather Statement
National Weather Service Topeka KS
529 PM CDT Sun Aug 9 2020

KSZ054-058-059-092315-
Coffey-Lyon-Anderson-
529 PM CDT Sun Aug 9 2020

...SIGNIFICANT WEATHER ADVISORY FOR ANDERSON...COFFEY AND SOUTHERN
LYON COUNTIES UNTIL 615 PM CDT...

At 527 PM CDT, automated weather observations reported strong winds
from showers and thunderstorms that could gust up to 55 mph. Winds
up to 50 mph have been reported near Emporia and Elmdale. It is
possible you may hear no thunder and have little to no rain with
these strong winds.

Locations impacted include...
Emporia, Garnett, Burlington, Lebo, Olpe, Colony, New Strawn,
Hartford, Gridley, Neosho Rapids, Westphalia, Kincaid, Lone Elm,
Harris, John Redmond Reservoir and Le Roy.

This includes the following highways...
 Interstate 35 between mile markers 128 and 146.
 Kansas Turnpike between mile markers 117 and 132.

LAT...LON 3817 9596 3817 9636 3850 9635 3851 9635
      3828 9506 3804 9508 3804 9596
TIME...MOT...LOC 2227Z 278DEG 33KT 3830 9662 3806 9533

Skow

Special weather statement, Aug 9, 6:40 PM CDT, 5 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 3:17 AM CDT	Special Weather Statement	TOP	Clay	43 min
Aug 9, 3:18 AM CDT	Heat Advisory	TOP	Anderson, Brown, Clay, Coffey, Dickinson, Douglas and 15 more	17 hr
Aug 9, 4:04 AM CDT	Special Weather Statement	TOP	Dickinson	41 min
Aug 9, 4:44 AM CDT	Special Weather Statement	TOP	Clay	46 min
Aug 9, 6:35 AM CDT	Special Weather Statement	TOP	Morris	40 min
Aug 9, 6:51 AM CDT	Special Weather Statement	TOP	Morris	24 min
Aug 9, 7:40 AM CDT	Special Weather Statement	TOP	Douglas	20 min
Aug 9, 7:45 AM CDT	Special Weather Statement	TOP	Douglas	30 min
Aug 9, 5:29 PM CDT	Special Weather Statement	TOP	Anderson, Coffey, Lyon	46 min
Aug 9, 6:40 PM CDT	Special Weather Statement	TOP	Coffey	20 min

Nearby

Severe Thunderstorm Warnings in Kansas, 2020 Every severe thunderstorm warning in 2020

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.