Partial Success?

Well, the balloon definitely went up and we got some good GPS locations from it. The text messages received from the balloon fairly closely followed the University of Wyoming's balloon prediction tool. The problem is that we stopped receiving texts, the balloon was definitely still on its way up, and it's now past the 4 hour battery life of the payload. Tomorrow we're going to make a futile effort to find where it landed based on the prediction model, but it's pretty well a lost cause now. The worst part is that I completely forgot to write my phone number on the payload, so there really isn't any hope of getting it back. I'm going to send a picture to all the sheriff's departments in the area just in case.
I hope anyone reading this blog has enjoyed the challenges and successes. If I happen to find the payload or if it comes back to me somehow I'll be certain to post it here. The last known location was  46.082375°, -107.913120°

UPDATE...not that good of one....
After searching for the balloon based on the UWYO flight prediction and some extrapolation we didn't find anything. I have sent a text message to the cellular number just in case someone finds it and is clever enough to try the SIM in a phone. I'll leave the SIM active for a month and monitor activity on the line. The flight path and the data received from the flight computer are shown below. Since the altitude reporting from the balloon wasn't working I can't say exactly how high it was when I received the last text, but if the model is any indication it was above 60,000 feet. There was a cell tower almost directly beneath the balloon at that time and the antenna on the balloon was oriented so the major lobe of radiation was directed downwards. I've removed some outlier points from the flight computer reports, but you can see that it followed the UWYO model very closely until the last two reported points. Even at the last two you can see that it was turning the corner like the model had shown. My best guess is that it burst and landed somewhere that there was no cell coverage. I am really kicking myself for not writing my phone number on the payload...lesson learned for next time.
With the balloon searching out of the way I have enjoyed the last three days in Yellowstone National Park with my dad and Arhan. This was the real reason for my trip to Montana, the balloon was just a fun experiment and challenge. I'm considering a second balloon since I have most of the hardware, but next time I'll add in a zigbee radio and a much larger battery.

Purple is the model and the yellow pins are the received data from the flight computer

Yellowstone traffic jam...damn buffalo

Arhan and I at the start of the Blacktail Deer Creek trail

Dad and I at the top of the Beartooth Pass about 10,500 feet elevation