Wind Shear
...is certainly not to be ruled out (yet), although the METAR posted earlier showed "NOSIG."
The event as reported so far (including rain columns visible in the background of the picture) is consistent with wind shear, but also consistent with other possibilities.
One way or the other, this one will likely be solved fairly rapidly, unless it turns out to be an obscure mechanical problem that takes digging.
Last edited by pattern_is_full; 13th Apr 2013 at 19:51.