Storm chaser arrested

Brian Barnes of Violent Skies Tours was arrested on May 6 for basically storm chasing. The official violation was obstruction of a highway or other passage way. He was parked at a rest stop, with plenty of room for other vehicles to get by.
Here are a few links to stories covering the incident:
News West 9 - has some good video of the arrest
CBS 7 - another account
ABC 33/40 - has Brian's original post to a weather list
Here is some edited commentary I posted on the same weather list I subscribe to:

An arresting officer has to have a valid reason for arresting someone, and not following his orders is not one of them. Here's a nice little wiki on false arrest:
http://en.wikipedia.org/wiki/False_arrest
I don't know Texas arrest laws in detail, but some things are common in all 50 states. Miranda rights for one, if Brian was asked any questions, I wonder if Brian was read his? Also, Brian should have been told at the time of arrest why he was being arrested; the exact criminal offense. As the wiki article mentions, in the case of a misdemeanor, he should only have been detained long enough for identification and to issue a summons (ticket). If it actually took 5 hours for them to tell you what you were charged with, then this should be an easy false arrest case (imo).
(Whether the officer was) Untrained about the weather or not, unless the passengers of the van are being held against their will (they, in fact, wished to be there, or they would not be on a tour), he can't just arrest Brian because he refuses to move. He could barricade the entrance to the rest area, etc, but unless Brian was breaking the law, he can't force him to move. He could even issue him a citation to be fought in court later for a misdemeanor parking violation if he thinks he's parked wrong, but again, he can't arrest him for just not following his orders. If that were the case, police could use that to arrest anyone, anytime.
I can think of any number of ridiculous scenarios following that logic.

I would like to think I would have done the same thing had I been in Brian's shoes, but sometimes I'm too nice... Although in this situation, after seeing the video, I think I might have just done the same thing.