Roughly 90% of all lightning strike are transferring negative charge from the cloud to ground. So a positive lightning strike (moving positive charge from the cloud to ground) is a rare occurrence. Positive lightning strikes tend to be generated by severe thunderstorms and contain much higher peak currents and charge transfers.
On March 31, a big positive lightning strike hit a home in Burningtown, NC. The strike ignited the structure and it burned to the ground. Luckily the resident escaped without harm.
See the news article here: