Storm Events Database

Storm Events Database

Event Details

Event Thunderstorm Wind
Magnitude 52 kts.
State NEBRASKA
County/Area HOWARD
WFO GID
Begin Date 05/11/2011 14:00:00 CST-6
Begin Range 8
Begin Azimuth N
Begin Location ST PAUL
Begin Lat/Lon 41.34/-98.47
End Date 05/11/2011 14:00:00 CST-6
Deaths Direct/Indirect 0/0 (fatality details below, when available...)
Injuries Direct/Indirect 0/0
Property Damage 0.00K
Crop Damage 0.00K
Episode Narrative After a rather quiet start to the severe weather season in South Central Nebraska, things changed in a hurry during the early to mid afternoon hours on this Wednesday as a line of severe thunderstorms marched from southwest to northeast across much of the area, but primarily impacting counties along and east of Highway 281. Although widespread straight line wind damage was the main story, there were also three confirmed tornadoes embedded within the line, consisting of an EF0 in extreme southern Adams County, an EF1 several miles north of Hampton in Hamilton County, and another EF1 that actually touched down on the edge of Osceola in Polk County. These tornadoes were relatively short-track, but did cause some damage. In terms of straight line wind damage, one of the many reports included 22 vehicles with rear or side windows blown out by flying gravel at Sandy Creek School south of Clay Center. There were only a handful of hail reports, none of which were larger than nickels. No injuries were reported from these storms.

The primary driving force for severe weather was a powerful, negatively tilted mid and upper level low pressure system centered over Colorado. At the surface, a fairly well-defined quasi-stationary front extended across the region from southeast Colorado to east-central Nebraska, with a few areas of low pressure along it. This surface front marked a sharp division in instability, with mid-day mixed-layer CAPE values ranging from negligible across western portions of South Central Nebraska, to between 1500-2500 J/kg in eastern counties. Deep layer vertical wind shear on the order of 30-50 knots was also present, making the environment conducive to fairly widespread severe storm development.

Focusing on storm mode and timing, the nearly solid line of severe storms lifted northeast across South Central Nebraska in a generally west-northwest to east-southeast orientation, first crossing into the state out of north central Kansas around 1 PM CDT, and eventually exiting the Polk and Nance County areas around 4 PM CDT. While strong to severe wind gusts of 50-70 MPH were common across several counties, the brief tornadoes were likely a result of the line of storms encountering enhanced low level shear and easterly low-level winds along and north of the quasi-stationary front.
Event Narrative Wind gusts were estimated at 60 mph.


All events for this episode:

Location County/Zone St. Date Time T.Z. Type Mag Dth Inj PrD CrD
Totals: 0 0 340.00K 0.00K
DESHLER THAYER CO. NE 05/11/2011 12:35 CST-6 Hail 0.75 in. 0 0 0.00K 0.00K
AYR ADAMS CO. NE 05/11/2011 12:40 CST-6 Tornado EF0 0 0 25.00K 0.00K
HEBRON THAYER CO. NE 05/11/2011 12:43 CST-6 Hail 0.88 in. 0 0 0.00K 0.00K
CARLETON THAYER CO. NE 05/11/2011 12:58 CST-6 Hail 0.75 in. 0 0 0.00K 0.00K
FAIRFIELD CLAY CO. NE 05/11/2011 13:00 CST-6 Thunderstorm Wind 52 kts. EG 0 0 30.00K 0.00K
HENDERSON YORK CO. NE 05/11/2011 13:32 CST-6 Thunderstorm Wind 52 kts. EG 0 0 0.00K 0.00K
KRONBORG HAMILTON CO. NE 05/11/2011 13:50 CST-6 Tornado EF1 0 0 150.00K 0.00K
OSCEOLA POLK CO. NE 05/11/2011 14:00 CST-6 Tornado EF1 0 0 100.00K 0.00K
ST PAUL HOWARD CO. NE 05/11/2011 14:00 CST-6 Thunderstorm Wind 52 kts. EG 0 0 0.00K 0.00K
SWEDEHOME POLK CO. NE 05/11/2011 14:02 CST-6 Thunderstorm Wind 61 kts. EG 0 0 35.00K 0.00K
OSCEOLA POLK CO. NE 05/11/2011 14:03 CST-6 Thunderstorm Wind 55 kts. MG 0 0 0.00K 0.00K
STROMSBURG POLK CO. NE 05/11/2011 14:15 CST-6 Thunderstorm Wind 52 kts. EG 0 0 0.00K 0.00K
GENOA NANCE CO. NE 05/11/2011 14:32 CST-6 Thunderstorm Wind 61 kts. EG 0 0 0.00K 0.00K
Totals: 0 0 340.00K 0.00K