Alert archive / Nebraska / Tornado Watches in 2013
Tornado Watch 539
The Storm Prediction Center issued this tornado watch at Oct 4, 2013, 2:38 PM CDT for 18 counties in Iowa; 32 counties in Nebraska. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Oct 4, 2013, 2:38 PM CDT (19:38 UTC)
- Expired
- Oct 4, 2013, 9:37 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 3 in
- Strongest gust expected
- 65 kt
All 50 counties
Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Fremont County, IA, Harrison County, IA, Ida County, IA, Mills County, IA, Monona County, IA, Montgomery County, IA, O'Brien County, IA, Osceola County, IA, Page County, IA, Plymouth County, IA, Pottawattamie County, IA, Shelby County, IA, Sioux County, IA, Woodbury County, IA, Antelope County, NE, Boone County, NE, Burt County, NE, Butler County, NE, Cass County, NE, Cedar County, NE, Colfax County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Douglas County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Knox County, NE, Lancaster County, NE, Madison County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Pierce County, NE, Platte County, NE, Richardson County, NE, Saline County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE, Wayne County, NE
The radar
The Omaha radar (KOAX), 46 km from the middle of the area, began a volume at 19:38 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
- 70%
- One or more EF2 to EF5 tornadoes
- 30%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 70%
- One or more hailstones of 2 inches or more
- 50%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
29 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 4, 4:43 PM CDT | Tornado Warning | OAX | Stanton, Wayne | 32 min |
| Oct 4, 5:01 PM CDT | Tornado Warning | OAX | Cedar, Stanton, Wayne | 29 min |
| Oct 4, 5:11 PM CDT | Severe Thunderstorm Warning | OAX | Antelope, Knox, Pierce | 49 min |
| Oct 4, 5:16 PM CDT | Severe Thunderstorm Warning | OAX | Johnson, Nemaha, Pawnee | 29 min |
| Oct 4, 5:20 PM CDT | Tornado Warning | FSD | Dixon | 40 min |
| Oct 4, 5:22 PM CDT | Tornado Warning | OAX | Antelope, Knox | 38 min |
| Oct 4, 5:28 PM CDT | Tornado Warning | OAX | Wayne | 32 min |
| Oct 4, 5:37 PM CDT | Tornado Warning | OAX | Cedar, Knox | 23 min |
| Oct 4, 5:45 PM CDT | Severe Thunderstorm Warning | OAX | Otoe | 30 min |
| Oct 4, 5:45 PM CDT | Tornado Warning | OAX | Thurston | 45 min |
| Oct 4, 5:48 PM CDT | Tornado Warning | FSD | Dakota, Dixon | 42 min |
| Oct 4, 6:03 PM CDT | Severe Thunderstorm Warning | OAX | Fremont, Mills | 27 min |
| Oct 4, 6:04 PM CDT | Tornado Warning | OAX | Monona | 41 min |
| Oct 4, 6:07 PM CDT | Tornado Warning | FSD | Woodbury | 38 min |
| Oct 4, 6:11 PM CDT | Tornado Warning | FSD | Plymouth | 49 min |
| Oct 4, 6:16 PM CDT | Tornado Warning | FSD | Dixon | 29 min |
| Oct 4, 6:23 PM CDT | Severe Thunderstorm Warning | OAX | Mills | 37 min |
| Oct 4, 6:26 PM CDT | Severe Thunderstorm Warning | OAX | Mills, Pottawattamie | 34 min |
| Oct 4, 6:43 PM CDT | Tornado Warning | FSD | Cherokee, Ida, Plymouth, Woodbury | 47 min |
| Oct 4, 6:55 PM CDT | Tornado Warning | FSD | Plymouth, Sioux | 50 min |
| Oct 4, 6:57 PM CDT | Tornado Warning | FSD | Plymouth | 18 min |
| Oct 4, 7:11 PM CDT | Severe Thunderstorm Warning | OAX | Fremont, Mills, Montgomery, Page | 34 min |
| Oct 4, 7:22 PM CDT | Tornado Warning | FSD | Cherokee | 38 min |
| Oct 4, 7:25 PM CDT | Tornado Warning | FSD | Plymouth | 35 min |
| Oct 4, 7:42 PM CDT | Tornado Warning | OAX | Mills, Montgomery, Page, Pottawattamie | 33 min |
| Oct 4, 7:54 PM CDT | Tornado Warning | FSD | Buena Vista, Cherokee | 36 min |
| Oct 4, 8:27 PM CDT | Tornado Warning | FSD | Buena Vista, Clay | 33 min |
| Oct 4, 8:33 PM CDT | Severe Thunderstorm Warning | FSD | Buena Vista | 42 min |
| Oct 4, 8:55 PM CDT | Tornado Warning | FSD | Clay | 20 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
Omaha, NE (KOAX), launched 12:00Z, 7.6 hours before the alert went out and 45 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
- 97 J/kg
- Mixed-layer CIN
- -211 J/kg
- Mixed-layer LCL
- 898 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 76 m²/s²
- 0-3 km storm-relative helicity
- 128 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 4.9
The text
As transmitted, in the capitals the NWS used until 2016.
889
WWUS20 KWNS 041938
SEL9
SPC WW 041938
IAZ000-NEZ000-050300-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 539
NWS STORM PREDICTION CENTER NORMAN OK
240 PM CDT FRI OCT 4 2013
THE NWS STORM PREDICTION CENTER HAS ISSUED A
* TORNADO WATCH FOR PORTIONS OF
WESTERN IOWA
EASTERN NEBRASKA
* EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 240 PM UNTIL
1000 PM CDT.
* PRIMARY THREATS INCLUDE...
SEVERAL TORNADOES LIKELY WITH A FEW INTENSE TORNADOES POSSIBLE
SEVERAL VERY LARGE HAIL EVENTS TO 3 INCHES IN DIAMETER POSSIBLE
SEVERAL DAMAGING WIND GUSTS WITH A FEW SIGNIFICANT GUSTS TO 75
MPH POSSIBLE
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 65 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES WEST OF FALLS CITY
NEBRASKA TO 35 MILES NORTHEAST OF NORFOLK NEBRASKA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU9).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.
&&
DISCUSSION...THUNDERSTORMS ARE EXPECTED TO FORM THIS AFTERNOON
ALONG/AHEAD OF AN APPROACHING COLD FRONT OVER EASTERN NEB. THOSE
STORMS WILL TRACK EAST-NORTHEASTWARD ACROSS THE WATCH AREA THROUGH
THIS EVENING. SUPERCELLS CAPABLE OF VERY LARGE HAIL AND A FEW
TORNADOES ARE POSSIBLE. LOCALLY DAMAGING WINDS ARE ALSO A CONCERN.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 25035.
...HARTSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 3, 7:32 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Cass, Clarke, Dallas and 23 more | 2 hr |
| Oct 3, 8:16 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Adams, Appanoose, Audubon, Benton, Black Hawk and 49 more | 9 hr |
| Oct 3, 9:13 PM CDT | Tornado Watch | SPC | Fremont, Mills, Montgomery, Page, Pottawattamie | 5 hr |
| Oct 3, 11:42 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Benton, Boone and 41 more | 93 min |
| Oct 4, 2:06 AM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Benton, Black Hawk and 70 more | 84 min |
| Oct 4, 4:35 AM CDT | Mesoscale Discussion | SPC | Benton, Cedar, Clinton, Jackson, Jones, Linn | 85 min |
| Oct 4, 9:03 AM CDT | Mesoscale Discussion | SPC | Appanoose, Cedar, Clinton, Davis, Decatur, Des Moines and 15 more | 87 min |
| Oct 4, 1:28 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Boone, Calhoun and 36 more | 2 hr |
| Oct 4, 5:20 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Audubon, Buena Vista, Carroll, Cass and 20 more | 85 min |
| Oct 4, 6:42 PM CDT | Tornado Watch | SPC | Adair, Adams, Audubon, Boone, Calhoun, Carroll and 29 more | 5 hr |
| Oct 4, 3:11 PM CDT | Severe Thunderstorm Watch | SPC | Andrew, Atchison, Buchanan, Clay, Clinton, DeKalb and 6 more | 9 hr |
Nearby
Tornado Watches in Nebraska, 2013Tornado Watches in Iowa, 2013Every tornado watch in 2013
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.