Chase Log 5-23-08; Darren Clabo

 

Chasers:

            Vehicle 1: Shawn Jacobs, Joanna George, Darren Clabo, Shawn Honomichl, Butch (the dog)

 

A review of the morning upper air features revealed a cut off 500mb low centered over the inter-mountain west. A surface map showed a low pressure over northwestern CO. A warm front extended ESE from the low through northern CO and Kansas. A theta-e plume was riding the warm front into SE WY. Forecast soundings showed the best 0-1km helicities near Cheyenne, WY at 20Z and near Torrington, WY at 00Z.

 

The best instability though was south of the warm front, so our decided target was basically for the far southeastern NE panhandle. This would give us plenty of road options for any last minute forecast changes. We stopped in Bridgeport, NE for some Wi-Fi and proceeded to note a massive outflow boundary clearing out the entire NE panhandle. We knew that this boundary would interact with the warm front to our south, possibly producing supercells. We continued southward to Sydney, NE and spontaneously met up with John Wetenkamp and Matt Bunkers from the NWS-RAP office.

 

We decided to head west on I-80 because storms that had moved north of the warm front were tending to produce tornadoes, and there was convection firing to the south (with the occasional reported landspout). We crossed the WY border and headed north towards Albin after a quick data stop. We encountered extensive pea-sized hail and very heavy rain. We ‘blindly’ continued north and finally west towards La Grange, WY. At this point, a tornado warning was issued for a storm in the county we were in, but the point location of the warning must have been wrong. As we got out of the precipitation we were in, we noted a very vigorous updraft to our NW. We neared highway 85, and headed north quickly realizing we were witnessing 3 funnel clouds (one of which appeared to be the roping stage of a tornado).

 

The mesocyclone was rotating rapidly and soon dropped a tornado (~6pm) that was visibly on the ground for about 4 minutes damaging the roof of one mobile home west of Hawk Springs. The storm headed directly north, us following, and kept a distinct funnel for almost 20 minutes. We couldn’t verify tornadic circulation at the ground, but the funnel was so low, it wouldn’t have been out of the question. This storm slowly dissipated and the chase crew headed for home through Scottsbluff and Chadron.

 

Summary:

            Features seen: ~4min tornado, 20 minutes of funnels

            Notes: Extensive small hail was encountered previous to tornado

 

Video Stills:

 

 

Radar images