If we are including zombies, I’m also assuming aliens are on the table.

So I’ll go with Independence Day and Mars Attacks! Twister is also up there for me but it’s not so much on a mega scale as most disaster flicks.

Then The Big Short counts. Great film. Someone should make a film on the Beirut explosion. 

https://www.imdb.com/title/tt16120140/

For zombie movies, my fav is Dawn of the Dead (1978). The mall scenes are awesome!

(Also, shout out to Legit. How about threads about best movie in black & white, best non-english speaking movie, and best road trip movie?)

My vote actually goes to a little-known British mockumentary called Smallpox 2002: Silent Weapon which follows a fictional pandemic of the now-eradicated disease. It's really well researched and creepily realistic.

Another favourite of mine is Dante's Peak, a 1997 flick about a volcanic eruption that's a fun ride.
Contagion and Twister are right up there for me too.

Interesting fact about smallpox, only 2 labs on the planet have live samples of it.

Yeah I find it fascinating; the disease was one of my special interests for a while.

It used to kill around 2 million people a year as recently as the 60s, and killed more people in the 20th century than all that century's wars combined. We managed to eradicate it from the wild cos it can only infect humans, so if you starve it of hosts it dies out.

Scary part is, while only two labs are officially supposed to contain the virus, in 2014 someone found some old vials of it at a back of a NIH freezer:

https://www.science.org/content/article/six-vials-smallpox-discovered-us-lab

Dawn of the Dead is so great, seen it a thousand and one times

The Day After Tomorrow is one of my favorites that comes to mind.

I am Legend was cool, and can't wait for the sequel to come out.  I've read the graphic novel and it was very interesting.  There's also a novel but i haven't gotten that far into it.    War of the Worlds was alright.  I really appreciated seeing Tom Cruise in a role where he wasn't trying to be so overly serious.  It felt like you were seeing more of the real person behind the persona created by acting.  If he was looking at glass of milk in some movie, he'd dead-eye that milk.  I just don't get that level of intensity sometimes but whatevs.