Mrs. B knows you weather folks are working without a net.
She did it, too, for a few years early in her career.
Ad lib is what you do.
You don't have a script or the prompter to break your fall.
But you don't want to get careless and tumble into illogical and
ungrammatical language.
So let's go over a few common misspeaks.

"The thermometer is falling."

If that were the case, you'd have to worry about it crashing to the ground
and breaking.

Try this, instead:

  >The TEMPERATURE is falling.

"The temperatures are going to cool off."

Temperatures don't heat up or cool off.
The weather does.

"The winds are calm."

Wait a minute.
If the air is calm, there isn't any wind.
So winds can't be calm.
Mrs. B suggests:

  >The air is calm this evening.
or
  >There's no wind today.

In his book A Broadcast News Manual of Style, Ron MacDonald says to say
"the temperature is presently 60 degrees" is nonsense.
Mrs. B would have to agree.
"Presently" means "in a short time" or "soon."
What you may think you're saying is this:

  >The temperature is CURRENTLY 60 degrees."

But do you even need "currently"?
"Is" implies "now."
Think about it.

MacDonald tosses about another one:

"Three inches of rainfall has fallen."

Rainfall is rain that has already fallen, so...

  >Three inches of RAIN has fallen.

"We can expect a 40-percent chance of rainfall tomorrow."

A chance of rain, maybe, but not rainfall.
We predict rain; we measure rainfall, so...

  >We can expect a 40-percent chance of RAIN tomorrow.

And how about "rain shower activity"?
A shower is rain and an activity.
MacDonald calls this one a double-headed redundancy, so...

  >We're looking at a good chance of rain tomorrow.
or
  >We're looking at a good chance of a shower tomorrow.

Mrs. B predicts your next forecast will be logical and grammatical.

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