June 22, 2010

Statistics:

Initial Target: Omaha, NE
Departure: Goodland, KS 8:00 am CDT
Arrival: Malcom, IA 2:00 am CDT
Intercepts: Eagle Grove, IA
Tornadoes: 0
Hail: Non-Severe (not measured)
Wind: Non-Severe (not measured)
Features: RFD Gust Front
Miles: 858

Summary:

Warm front play across eastern NE and northern IA. Targeted the Omaha area for afternoon supercell initiation, but had to follow boundaries and storms into northern Iowa as initiation stalled and night chase unfolded. Followed dieing storm and orphaned anvil until double backing to new development northwest of Ames near Eagle Grove, IAafter dark. Noted HP structure but nothing tornadic, despite spotter reports. Ended chase as storms merged into cluster.

Crew and Equipment:

Solo chase.  Equipment:  Kenwood TH-F6A Tribander, Dell Inspiron Laptop.  Kyocera data card and router, Holux 236 GPS, Robotic camera dome with Sony XR-520V.

 

 

Details:

Tuesday was my third day chasing for this trip. Tornado action looked a little better than the previous day with a warm front providing enhanced directional shear. I initially targeted the Omaha area where models were indicating afternoon initiation under strong instability and directional shear.

This is where I spent the night after the chase the day before: the flatlands of northwest Kansas:

I made my way up to 80 and east to Omaha where I pulled off outside of town at a hotel to monitor data. The weather was absolutely miserable with dewpoints approaching the 80's. After living in my vehicle for the past three days and now sweating in the swamp air, I was dieing. I dumped some water on my head and washed my hair. It was refreshing but the cool off lasted only a few minutes. I was hoping the oppressive humidity would help fuel afternoon supercells, but initiation held off from what the models predicted.

Storms finally went up right on the Missouri river and I followed them into Iowa. I gave chase behind the storm, never quite catching it until I realized it had died long ago and I was now chasing an orphaned anvil. I started to make my way home, fearing a bust as storms initiated to my northwest. Rather linear looking at first I feared they might be elevated junk. It wasn't until tornado warnings went out that I finally double backed for the intercept. I intercepted near the town of Eagle Grove, with the sirens blaring for a tornado warning. Spotters were reporting tornadoes on the storm, but as I went west of town the only thing I could make out was scuddy HP structure.

 

Spotting HP storms at night is extremely difficult, and with all the ragged lowerings I was starting to become convinced the reports coming in were false. One report was of a "wedge funnel" which is completely contradictory. There were some over eager spotters and chasers on these storms seeing things in the dark. I got a call from NWS Des Moines about the reports they were receiving, asking me for confirmation. They were not impressed with the reports they were getting. I informed them that I had seen nothing tornadic, but also had visibility limitations because I was south of the HP hook. I followed the storm on gravel roads until well after midnight before the cells finally merged into a cluster.

Conclusion:

Despite intercepting a tornado warned supercell, it came much later than I thought and with little observable structure other than a massive HP core. Most of the tornado reports that came in from Iowa on this day were probably false. There was some damage but it was more likely straight line wind damage. The NWS did not conduct damage surveys as they didn't have any evidence there actually were tornadoes. This chase was probably more of a bust than a noteworthy intercept. Iowa never fails to disappoint.

 

 

Lessons Learned: 

  • Don't trust reports from HP storms at night.