The Collaborative International Dictionary of English v.0.48:

Weather station \Weather station\ (Meteor.)
   A station for taking meteorological observations, making
   weather forecasts, or disseminating such information. Such
   stations are of the first order when they make observations
   of all the important elements either hourly or by
   self-registering instruments; of the second order when only
   important observations are taken; of the third order when
   simpler work is done, as to record rainfall and maximum and
   minimum temperatures.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

weather station
    n 1: one of a network of observation posts where meteorological
         data is recorded [syn: meteorological observation post,
         weather station]