Due to winter storm, California got grant to extend tax filing on Oct/16/2023, does this include payment if I owe tax? Where I could find official answer on this? Thanks!

The postponed deadline applies to payments as well as filing. But it's not for all of California. It depends on which storm you were affected by, and what county you live in. See the page at the link below on the IRS web site for more information. On that page, the "More Information" or "Detailed Information" link for the specific storm will lead you to the official IRS announcement with all the details.

https://www.irs.gov/newsroom/around-the-nation-california

Thanks a lot for your response!

I am unable to find "More Information" or "Detailed Information" in this link:

https://www.irs.gov/newsroom/around-the-nation-california

Would you please share the specific link for the information? Thanks !

It's in the first link listed on that IRS page.  First paragraph on this one

https://www.irs.gov/newsroom/irs-reminder-to-storm-victims-in-3-states-file-and-pay-by-oct-16-most-of-california-parts-of-alabama-and-georgia-affected 

When you click the plus sign for the specific storm date that you are interested in, you will see a link for "More Information" or "Detailed Information" for that particular storm.

Thank you very much for your clear and quick answers! Got it.