Alert archive / Kansas / Severe Thunderstorm Watches in 2012
Severe Thunderstorm Watch 587
The Storm Prediction Center issued this severe thunderstorm watch at Aug 23, 2012, 5:57 PM CDT for 30 counties in Kansas. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 23, 2012, 5:57 PM CDT (22:57 UTC)
- Expired
- Aug 23, 2012, 10:08 PM CDT
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 55 kt
All 30 counties
Barton County, KS, Cheyenne County, KS, Decatur County, KS, Ellis County, KS, Finney County, KS, Gove County, KS, Graham County, KS, Greeley County, KS, Hamilton County, KS, Hodgeman County, KS, Kearny County, KS, Lane County, KS, Logan County, KS, Ness County, KS, Norton County, KS, Osborne County, KS, Pawnee County, KS, Phillips County, KS, Rawlins County, KS, Rooks County, KS, Rush County, KS, Russell County, KS, Scott County, KS, Sheridan County, KS, Sherman County, KS, Smith County, KS, Thomas County, KS, Trego County, KS, Wallace County, KS, Wichita County, KS
The radar
The Goodland radar (KGLD), 101 km from the middle of the area, began a volume at 22:57 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 23, 7:20 PM CDT | Severe Thunderstorm Warning | GLD | Gove, Logan, Sheridan, Thomas | 40 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Dodge City, (KDDC), launched 12:00Z, 11.0 hours before the alert went out and 157 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.
- Mixed-layer CAPE
- 1075 J/kg
- Mixed-layer CIN
- -184 J/kg
- Mixed-layer LCL
- 897 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 221 m²/s²
- 0-3 km storm-relative helicity
- 332 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.0
The text
As transmitted, in the capitals the NWS used until 2016.
971
WWUS20 KWNS 232300
SEL7
SPC WW 232300
KSZ000-240600-
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 587
NWS STORM PREDICTION CENTER NORMAN OK
600 PM CDT THU AUG 23 2012
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
WESTERN KANSAS
EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 600 PM
UNTIL 100 AM CDT.
HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 65
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80
STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES NORTH
NORTHWEST OF HILL CITY KANSAS TO 20 MILES SOUTHEAST OF GARDEN
CITY KANSAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).
REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.
DISCUSSION...STORMS ARE GRADUALLY INCREASING OVER WRN/NORTH CENTRAL
KS NEAR A LOW LEVEL CONVERGENCE ZONE EXTENDING FROM A LOW OVER SERN
CO NEWD INTO NWRN KS. THE AIR MASS SOUTH OF THE FRONT IS WARM AND
UNSTABLE WITH MLCAPE AROUND 1500 J/KG. ALTHOUGH MID LEVEL WINDS ARE
MODEST AT BEST...STRONG DIRECTIONAL SHEAR WITH HEIGHT WILL ENHANCE
STORM ORGANIZATION AND INTENSITY WITH ORGANIZED MULTICELL STRUCTURES
LIKELY. AN INCREASE STORM COVERAGE IS EXPECTED THIS EVENING AS A
LOW LEVEL JET DEVELOPS INTO WRN KS AND THIS MAY AID IN STORM
MAINTENANCE INTO THE OVERNIGHT HOURS. LARGE HAIL AND STRONG WIND
GUSTS WILL BE POSSIBLE WITH STRONGER CELLS...AND SLOW STORM MOTION
SUGGEST ADDITIONAL THREAT OF LOCALIZED HEAVY RAIN.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 55
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
MOTION VECTOR 28015.
...WEISSSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 23, 3:20 PM CDT | Mesoscale Discussion | SPC | Decatur, Finney, Gove, Graham, Grant, Gray and 19 more | 55 min |
Nearby
Severe Thunderstorm Watches in Kansas, 2012Every severe thunderstorm watch in 2012
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.