foehn, chinook, katabatic winds.
dog days (of summer).
colder than the balls on a brass monkey.
whiteout / blizzard / ...
horizontal rain
snain (snow/rain blend)
thunder-bumpers
squall line
tornado weather
fry an egg on the sidewalk
'good sleeping weather' (seldom observed in my current locale!)
typhoon/cyclone/willy-willy/tornado/dust devils/water spouts/ ... (cyclone meaning tornado in some areas, but not others)