Expect has a "weather" command supplied as an example in its source distribution. "However, note that the version in Expect needs a modification to handle a new web site location for the weather information, and that new site requires the machine doing the request be located in reverse dns lookup or it refuses to provide data." [June 2002, LV ]
"A little rain forecaster", Jason Tang's tclweather applet, Iain B. Findleton's collection of weather-related Tcl fltk demonstrations, and ... are all interesting.
Several of the documented TclSOAP examples focus on weather data.
Also, see Jstrack, tclMetarGUI