2.7 kilotons. Hiroshima was about 15 kilotons.
Of course in this case the 2.7 kiloton blast was caused by 2.7 kilotons of explosive. In the Hiroshima case, the 15 kt blast was caused by something that weighed a bit less than five tons, or 0.005 kilotons.
Ammonium nitrate isn’t as explosive as TNT. So it isn’t a direct comparison.
Thats what I read. Local media are reporting that 2,700 tonnes of the chemical exploded, which scientists making initial calculations said was about three kilotonnes of TNT - roughly a fifth of the Little Boy atomic bomb dropped on Hiroshima in the Second World War.
(Amonium nitrate)
“2.7 kilotons”
Well, it would be 2.7 kilotons if it were 2700 tons of TNT. ANFO is only about 80% as powerful as TNT, so more like 2.2 kilotons.
2.7 kilotons of ammonium-nitrate produces nothing like 2.7 kT of explosive yield. Actually, as a measure of explosive energy one kiloton is exactly one-billion calories, the kiloton moniker is merely a convenience. The explosive energy of ammonium nitrate is 230 cal/gm which would make 2.7 kilotons of ammonium-nitrate equivalent in yield to about 0.62 kilotons.
https://www.nature.com/articles/195277a0
I am extremely skeptical of the “ammonium nitrate” explanation. The more plausible explanation is that the warehouse was a Hezbollah ammunition depot, and that that ammunition was intended for Israel. Unless they could divert it to use against U.S. troops in the area.