weather induced colic

[Victoria A Thompson <toriandsteve@juno.com>]

If anybody out there has or has had a horse that would colic when the
weather would change I sure wish you would give me some hints on how you
were able to stop or prevent the occurrence of this nasty little trick.  

Taffy has coliced twice now (on Oct. 31 and just this past Saturday) with
the exact same conditions.  A warm day with rain called for that night or
early the next morning.  We went for a short ride (1 1/2 hours) very easy
(mostly walking on flat ground).  Five minutes from home she stopped dead
in her tracks and started pawing the ground.  Suffice it to say from
there it was colic.  Vet visit the whole nine yards.  These were not
severe colics, but banamine and dipyrone were used to ease the pain (not
together).  She would gradually eat mineral oil laced bran so we didn't
have to tube oil her.  She would have one or two bad hours where she
would want to roll, but mostly she would just lay quietly in between
trips to the mash bucket.  She's young (8) and in excellent health.  She
is fed mostly oat hay with a little alfalfa and some grass hay.  She gets
about a pound or less of Omelene 200 with a couple of pounds of carrots. 
My vet is pretty sure it's weather induced because we can't find anything
wrong.  

It's only happened twice, but I'd like to try and not let it happen
again.  Any hints?

Thanks,      Tori  (and Taffy)