Can a power surge cause amp to clip?

If there was an audible sound heard from the speakers as a result of a power surge it’s very possible the amp clipped while making it.  If it did it could damage the speakers.   Check everything out.  Hopefully sounds same as prior and everything works.   

Don't you have to be playing something to clip?

Yes. The OP is most likely using the wrong terminology.

(Unless he plays music all night long).

You don’t need clipping for a power surge to cause damage to gear but it’s possible and perhaps even likely clipping occurred as a result if you heard a sound from the speakers as a result of a power surge.

The issue is the power surge.   Avoid those in any way possible like turning off and even unplugging gear during thunder storms. 

thanks for the responses. there was no input to the amp when the clipping sound was made by the speakers. My guess is perhaps the grid had a surge, or the lighting was close enough to me that the magnetic field directly induced some current in the analogue cables going from the DAC to the amp. The amplitude was so large such that it clipped.
The troubling thing is that I heard it more than once. Again a day later, during the day. My area was going through a heat wave and the strain on the grid could be leading to problems with power surges.
Just wondering if a surge alone (without lighting) can cause clipping.

No, power surges do not cause clipping. What it might cause is your DAC to output a signal (noise) that is so high amplitude it overdrives the amp. Either way the sound you heard is not clipping. Whatever it is we can guess but of that we can be sure.