Looking at the weather condition it seems that the water supply either from the tank or hydrant must be freezing.
Added by Bomba Boy on 28 January 2009.
A "cold snap" - clear sky - so cold dense air mass, unusual, for new orleans - possibly down from the great plains or (gasp!) even canada.
the cars are covered with water-spray, from the hoses and maybe from the snorkel[hp], which has frozen on the cars' cold metal, and everything else in the vicinity, including the fire-crews - brrrr.
new orleans is mississippi river delta-land, very low; like the netherlands, protected with levees [dikes - except when hurricane katrina came along august, 2005].
so the water table is close to the surface; the frost wouldn't have penetrated down to the pipes; so things are ok as long as you keep the water flowing up top; and the trucks' tanks are not kept static for too long out in the cold.
a very rare shot for that area - but, all too familiar for us in the great white north (>:]
Pat when I first looked at this I thought the foam tender had been out to play! Amazing weather, and Canadians are always to blame for the weather, or so Americans tell me!
Added by Bomba Boy on 28 January 2009.