you tell me, is the weather proving to be any benefit, or dealing with more tough conditions? >> reporter: u.s. a bit of both, actually, chris. winds problematic. shipping back and forth. strong at times and that could shift debris if you are trying to do a search or a building that's weakened by the blast. the rain clears the air, helps wash particles out. toxics, things like that. it helps when it comes to any kind of environmental hazard. but it has slowed at least, the search and rescue effort and it will help stabilize fires and put those embers out. good and bad. daylight is the biggest help they have now. >> all right, martin, we'll check back with you, to explain to you at home, the reason that this weather may be a little bit helpful with the chemical compound they are worried about, anhydrous ammonia means without water. it turns into a vapor, dry, can be weighed down by water, tamped into the ground. that's what we hope happens here. the continuing risk, fire is not