Fun with the English language

I copied this from our NWS forecast for today:

NOW
LONG PERIODS OF SNOW WILL CONTINUE ACROSS ____________ THROUGH
11 AM. SNOW ACCUMULATION WILL GENERALLY BE LIGHT, AROUND ONE TENTH OF
AN INCH, WITH SOME ISOLATED AREAS RECEIVING AROUND THREE TENTHS OF AN
INCH. CONDITIONS MAY BE SLICK AND HAZARDOUS, SO IF YOU ARE DRIVING,
USE EXTRA CAUTIONS.

MEGR

TODAY
BLUSTERY. FLURRIES LIKELY WITH A CHANCE OF SNOW SHOWERS
SNOW SHOWERS. TEMPERATURES SLOWLY STEADY OR SLOWLY FALLING INTO
THE UPPER 20S. WEST WINDS 15 TO 25 MPH WITH GUSTS TO AROUND 40 MPH.
CHANCE OF SNOW 40 PERCENT.

OK, three things:
1. Who measures snowfall in tenths of inches?
2. Use extra "cautions"?
3. How exactly do you get temperatures that are "slowly steady"?