We started out the day in Hastings on Saturday looking at internet weather data from the public library and decided to target the area of storms moving east from the McCook, Nebraska region.  This area was in the tongue of high CAPE and good theta-E advection with dewpoints pooling into the 60's north of a surface low over north central Kansas.  We were concerned with the 700 millibar warm cap of around 10 degrees Celsius and if we were going to break the cap before dark in the Hastings area.  So we left the library around 330 pm and drove west to get in front of severe storms developing rapidly near McCook, Nebraska. 

We noticed some large lowerings to the west around 530 pm in Furnas county but missed seeing the large high contrast tornado viewed by Roger Hill, Matt Crowther, and others.

We got to Alma about 6 pm and drove to a higher location on the north side of town.  At 6:02 pm, we saw a very narrow developing funnel about 5 miles west northwest of us next to a rain shaft.  At 6:03, it was producing debris and the condensation had touched the ground.  It then got wider with an elephant trunk shape with more debris. We then needed to move a bit south because it was moving straight towards us.  It was getting very hard to see at 6:08 pm, was getting rain and hail wrapped, and getting closer, so we decided to bail out of Alma and get east of Alma on Highway 136.  The storm started to race eastward as the strong rear flank downdraft (RFD) outflow was pushing outward.  The strong circulation with an RFD notch stayed north of the highway and kept trying to put down more funnels, but cannot confirm more tornados after 6:08 pm.  This storm system was hard to stay ahead of as we raced several times east to get ahead of the downdraft.  We then saw the herds of storm chase vehicles, maybe 20 cars in a row, all traveling east along with the Doppler On Wheels (Dows).  We ended the chase at Hebron at dark and had another supercell chase us back to a gas station for cover.  We were getting quarter size hail while the tornado sirens were blaring about dark or 9 pm. 

 

All in all an incredible day with over 80 tornados reported.  This day goes down in history as one of the top 10 most active tornado days on record.  We are also saddened to hear of the loss of life and property in the Hallam area of Lancaster County.  This damage was caused by another supercell thunderstorm ahead of the Alma storm and later in the afternoon.  A preliminary investigation shows F3 damage on the Fujita scale around Hallam and will probably be rated higher pending further investigation.