The Homs Explosion Looks Like A Low-yield Nuke (update 1)

After seeing the video of the explosion in Homs, Syria, and upon noting how the rising fireball continued to glow, I had a look at videos of a high-yield conventional explosion and a low-yield nuclear test explosion.

In a large conventional explosion, the chemical explosive tends to expend its energy near the ground and throw up a dark cloud of dust and spent chemical reactants, as is demonstrated by this explosion during the “Shock and Awe” aerial campaign over Baghdad:

At the 1:23 mark of this video, the high explosive begins to expend its energy at the point of detonation…

And by the 1:26 mark (3 seconds after), the bomb’s energy has been expended, and a dark cloud is thrown up…

Now compare that to this video of a 1KT nuclear test explosion:

The detonation occurs at the 0:21 mark, and is followed by a rising cloud that continues to glow as the nuclear material continues its fission. Here is the cloud at the 0:27 mark (6 seconds after the initial blast)…

…and the cloud continues to glow until the 0:32 mark (11 seconds after detonation).

In the Homs explosion, the blast occurs right as the video starts, and here is what the cloud looks like 6 seconds after…

…and it continues to glow until the 0:12 mark (12 seconds after detonation).

So I ask you, does the Homs explosion look more like the conventional explosion in Baghdad or the 1KT nuclear test explosion? My personal take is that it appears to be nuclear, and perhaps in the 5KT range. I see no good reason why a conventional explosion would continue to release energy in that way.

Folks, it appears we might have a nuclear war on our hands.

[Update 1 - Same Day]

Could the announced closure of US embassies on Sunday have anything to do with this blast? Are they anticipating blowback if the public catches on? Are they going to announce what happened over the weekend?