REPORT MAY 16 2004 ROCKVILLE, NEBRASKA TORNADOES
   
Tornado # 1 near Rockville, NE approx 6:50 PM
(click to enlarge)
[courtesy Jeff Gammons]


Tornado #2 NE of Rockville, NE
[courtesy Chris Collura & http://sky-chaser.com]


Jason Foster and I, along with the Weathervine gang and Scott Eubanks intercepted two tornadoes on a supercell that moved from Sherman to Howard County in southern Nebraska. We observed the first tornado near Rockville in southeastern Sherman County about 6:50 PM CST and the second near Boelus in southwestern Howard County about six minutes later. We were traveling southeast and then east on Nebraska State Road 58.

Our original target was Broken Bow, a location between the moisture and thermal axis and near the differential heating boundary stretching from southwest to northeast as cited by SPC in their MCD for the area. We believed the shortwave would likely help initiate storms along the boundary which would then move eastward into the low level jet and intensify. This is more or less what happened.

We learned of the storm in Gosper County south of Lexington and I-80, and raced south on 183 to position ourselves west of the updraft region. However, near the intersection of 30 and 183, the storm had moved near enough that we observed the first of a series of lowerings and rotating wall clouds that tracked through Buffalo County. To mirror the storm's northeastward movement we navigated through some slippery Bob's roads as the storm cycled several times, but without successful tornadogenesis.

As the storm reached the Sweetwater to Ravenna area, it intensified dramatically, morphing into a tall wedding cake appearance with strong inflow from the southeast. On 68 north of Ravenna, a large but elevated rotating wall cloud hung over the road directly in front of us. We decided to scoot underneath it as it looked somewhat disorganized and offered us a chance to regain a favorable viewing position. This was a fortuitous move since, about fifteen minutes later, the first cone shaped tornado touched down about four miles to our north. It was down about one minute, and, from Boelus looking north, we observed the second tornado five to seven minutes later, this time at a longer distance, perhaps six miles. Our second tornado also presented a conical appearance and lifted quickly.

Several intersections were jammed with chasers and tour buses, which we evaded rapidly. However, most drivers behaved sensibly and co-operated. Again I think the publicity of sites like Stormtrack and lists like wx-chase have disseminated the ideas of pulling off the road and using hazard lights and watching carefully before re-entering the roadway pretty well.

The images above belong to Jeff Gammons and Chris Collura and I appreciate their permission to use them.. I should have video of both tornadoes and will post grabs as soon as possible to replace their images.