Upon closer inspection

The weather person makes their predictions based on current conditions, and the things they can see heading our way. 

I think the lizards already know.  From my desk chair I see them climbing on the front of the house, and up and around the window screens.   They play, they do their push-ups, and every now and then they’ll leap from branch to shrub, or from house to flowerpot, and back again.

Before the first crack of thunder they have all disappeared.  Not a single lizard can be seen.  They must know.  They either all know, or they communicate with each other very quickly and very well.

I expect it’s the same with crows.   They wake me up in the early morning, hollering back and forth, and splashing around in the bird bath.  During the day I see them hopping around the yard picking out, what to them, must be tasty treats, bits of this and that, and of course catching the slower lizards.  They forage for their meals and play and just like the lizards, before the first raindrop hits, they are nowhere to be seen.

So I guess my question is…

Is the weather person looking at something called a Doppler, or are they simply watching the lizards?