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Hallam Nebraska Tornado

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Hallam Nebraska Tornado Track
Reflectivity 01:07Z (8:07 PM CDT) This radar image shows the supercell (high-precipitation supercell) as it was moving through Saline County. The red colors indicate very heavy rain or hail, with lighter rain indicated by the yellow, green, and blue colors. The tornado clipped the southern portion of the town of Wilber, with the main part of the tornado passing just south of Wilber. There is a hook echo that has completely wrapped around to form a "donut" shape echo between the towns of Wilber and De Witt. This donut echo is associated with the tornado.
Storm-Relative Velocity 01:07Z (8:07 CDT) This radar image shows the wind velocity within the supercell thunderstorm. The green and blue colors indicate winds blowing toward the radar, and the red, orange, and yellow colors indicate winds blowing away from the radar. Just southwest of Wilber the radar is showing a 105 mph wind blowing toward the radar, right next to a 69 mph wind blowing away from the radar. This is known as a "velocity couplet," and is often associated with the mesocyclone in the supercell. The radar typically does not actually measure the winds inside the tornado, but rather the "parent" mesocyclone that the tornado forms out of.
Reflecitivity 01:24Z (8:24 PM CDT) This reflectivity image shows a more classic looking hook echo, moving out of Saline County and into the northwest corner of Gage county and the southwest corner of Lancaster County. The hook echo, and the associated tornado, is between Hallam and Wilber.
Storm-Relative Velocity 01:24Z (8:24 CDT) At this time, the velocity image is showing winds of 90 mph blowing toward the radar, and 113 mph blowing away from the radar.
Reflectivity 01:28Z (8:28 PM CDT) The hook echo now stretches from the town of Claytonia to the town of Hallam
Storm-Relative Velocity 01:28Z (8:28 CDT) The velocity couplet is shown just west of Hallam, about to move into the Hallam area. The wind speeds, as indicated by the radar, in the mesocyclone are 83 mph toward the radar and 100 mph away from the radar.
Reflectivity 01:33Z (8:33 PM CDT) The hook echo at 8:33 PM completely engulfed the town of Hallam. This was when the tornado was near its widest point of approximately 2 ½ miles. The town of Hallam was near the northern edge of the tornado path.
Storm-Relative Velocity 01:33Z (8:33 CDT) The tornado was passing over Hallam at 8:33 PM, and the radar velocity winds were 79 mph toward the radar and 92 mph away from the radar. Because the radar is measuring the winds in the mesocyclone, the wind speeds do not necessarily correlate to the strength of the tornado, because the tornado was rated a F4 at the time of this radar image. There are many factors and variables which determine the radar's ability to measure the wind speeds inside the mesocyclone. Despite the slightly lower winds on the radar, this is still considered an extremely strong velocity couplet.

Some Storm damage photo's from Hallam

Destroyed home on the east side of Hallam.
A destroyed home and trees with all of their limbs gone in Hallam.
Collapsed home in Hallam.
Toppled center flow hopper cars in Hallam.
All the rooms are exposed in this damaged home in Hallam.
Collapsed remains of the United Methodist Church in Hallam.
A 100 year old farm house swept away by the tornado north of Firth. The family that lived in this home just moved into it the week prior to the tornado.
Some of the strongest damage occurred south and west of Hallam. Here is the foundation of a home just south of Hallam.
Picture of a van that was thrown from the school bus area and landing on the remains of a concession building near the Norris school football field.
This is the remains of the auditorium of the Norris High School. The roof was peeled off and the walls collapsed into the auditorium.
School busses that were tossed like toys near the Norris school.
A mini van that was tossed and a roof of the school that collapsed at the Norris school.
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