The asteroid that killed most of what you think of as dinosaurs was ~6-9 miles in diameter. It killed ~75% of life on earth, but a bunch of dinosaurs still made it through. There are currently twice as many bird species, as there are mammal species.
This thing sounds like a baby at 100-300 feet across, but that puts the minimum estimate (100 foot diameter) as a Tunguska explosion sized blast, which would be cataclysmic regionally.
For reference, Hiroshima was ~16 kilotons, Nagasaki was ~21 kilotons.
The Tunguska explosion happened in 1908 in the middle of Siberia. Tunguska was 3-50 megatons, most common estimate is ~15 megatons, close to 1000X the Hiroshima atomic bomb.
Tunguska may have been an asteroid, or maybe a comet, but whatever it was, likely airburst at an altitude of ~6 miles. It leveled ~800 sq. miles of trees and charred ~100 sq. miles of trees adjacent to the blast.
People felt the explosion in London and were able to see the light from it on the east coast of the US.
15 megatons is the most common estimate for Tunguska, so here's a nuke map estimate of a 15 megaton explosion hitting Houston.
100% probability of 3rd degree burns all the way from Sugar Land to La Porte. Again, this is the minimum predicted size, the asteroid could be up to 3X bigger.
If this asteroid does hit, it's going to obliterate anything it hits, so hope for the ocean.
The track posted upthread goes right over Mumbai, Calcutta and everything in between them, then Dhaka, the capital of Bangladesh. All of those are ~20 million each. Also Lagos at >13 million, Bogota at >10 million among others. For even the minimum possible size estimate, if it hit one of them, the death toll would be in the millions.
NASA made physical contact with a ~500 foot asteroid a couple of years ago, so hopefully no one working on that project has been purged. That institutional knowledge could wind up being pretty important.