Alert archive / Nebraska / Severe Thunderstorm Watches in 2009
Severe Thunderstorm Watch 593
The Storm Prediction Center issued this severe thunderstorm watch at Jul 17, 2009, 11:40 AM CDT for 11 counties in Kansas; 14 counties in Nebraska. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 17, 2009, 11:40 AM CDT (16:40 UTC)
- Expired
- Jul 17, 2009, 6:00 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2.5 in
- Strongest gust expected
- 60 kt
All 25 counties
Cheyenne County, KS, Decatur County, KS, Gove County, KS, Greeley County, KS, Logan County, KS, Rawlins County, KS, Sheridan County, KS, Sherman County, KS, Thomas County, KS, Wallace County, KS, Wichita County, KS, Arthur County, NE, Chase County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Garden County, NE, Grant County, NE, Hayes County, NE, Hitchcock County, NE, Keith County, NE, Lincoln County, NE, McPherson County, NE, Perkins County, NE, Red Willow County, NE
The radar
The North Platte radar (KLNX), 147 km from the middle of the area, began a volume at 16:42 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
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 60%
- One or more hailstones of 2 inches or more
- 60%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
22 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 17, 11:46 AM CDT | Severe Thunderstorm Warning | LBF | Arthur, Keith | 44 min |
| Jul 17, 11:57 AM CDT | Severe Thunderstorm Warning | LBF | Hayes | 33 min |
| Jul 17, 11:58 AM CDT | Severe Thunderstorm Warning | LBF | Chase, Perkins | 47 min |
| Jul 17, 12:05 PM CDT | Severe Thunderstorm Warning | LBF | Hayes, Lincoln | 40 min |
| Jul 17, 12:08 PM CDT | Severe Thunderstorm Warning | GLD | Hitchcock | 67 min |
| Jul 17, 12:26 PM CDT | Severe Thunderstorm Warning | LBF | Keith, Perkins | 49 min |
| Jul 17, 12:39 PM CDT | Severe Thunderstorm Warning | LBF | Chase | 51 min |
| Jul 17, 1:05 PM CDT | Severe Thunderstorm Warning | LBF | Chase, Perkins | 40 min |
| Jul 17, 1:07 PM CDT | Severe Thunderstorm Warning | GLD | Rawlins | 53 min |
| Jul 17, 1:22 PM CDT | Severe Thunderstorm Warning | GLD | Dundy | 53 min |
| Jul 17, 1:43 PM CDT | Severe Thunderstorm Warning | LBF | Chase | 47 min |
| Jul 17, 1:52 PM CDT | Severe Thunderstorm Warning | GLD | Thomas | 68 min |
| Jul 17, 2:39 PM CDT | Severe Thunderstorm Warning | GLD | Cheyenne | 66 min |
| Jul 17, 2:47 PM CDT | Severe Thunderstorm Warning | GLD | Logan | 58 min |
| Jul 17, 3:28 PM CDT | Severe Thunderstorm Warning | GLD | Cheyenne, Sherman | 62 min |
| Jul 17, 3:49 PM CDT | Severe Thunderstorm Warning | GLD | Sherman, Thomas | 37 min |
| Jul 17, 3:55 PM CDT | Severe Thunderstorm Warning | LBF | Arthur, Grant | 50 min |
| Jul 17, 4:21 PM CDT | Severe Thunderstorm Warning | GLD | Logan | 18 min |
| Jul 17, 4:24 PM CDT | Severe Thunderstorm Warning | LBF | Arthur, Garden | 51 min |
| Jul 17, 4:43 PM CDT | Severe Thunderstorm Warning | LBF | Arthur, Keith | 47 min |
| Jul 17, 5:07 PM CDT | Severe Thunderstorm Warning | LBF | Arthur, Garden, Keith | 38 min |
| Jul 17, 5:42 PM CDT | Severe Thunderstorm Warning | LBF | Deuel, Garden, Keith | 48 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
N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 4.7 hours before the alert went out and 73 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
- 11 J/kg
- Mixed-layer CIN
- -268 J/kg
- Mixed-layer LCL
- 983 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 7 m²/s²
- 0-3 km storm-relative helicity
- 118 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 17, 11:07 AM CDT | Mesoscale Discussion | SPC | Decatur, Rawlins, Sheridan | 83 min |
| Jul 17, 2:21 PM CDT | Mesoscale Discussion | SPC | Finney, Grant, Greeley, Hamilton, Haskell, Kearny and 6 more | 54 min |
| Jul 17, 2:58 PM CDT | Severe Thunderstorm Watch | SPC | Finney, Grant, Gray, Hamilton, Haskell, Kearny and 7 more | 7 hr |
| Jul 17, 3:15 PM CDT | Mesoscale Discussion | SPC | Cheyenne, Gove, Logan, Sherman, Thomas, Wallace | 30 min |
| Jul 17, 1:06 PM CDT | Mesoscale Discussion | SPC | Banner, Cheyenne, Kimball | 84 min |
| Jul 17, 1:59 PM CDT | Tornado Watch | SPC | Banner, Box Butte, Cheyenne, Kimball, Morrill, Scotts Bluff and 1 more | 6 hr |
Nearby
Severe Thunderstorm Watches in Nebraska, 2009Severe Thunderstorm Watches in Kansas, 2009Every severe thunderstorm watch in 2009
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.