Current observations - 4-character ICAO codes requiredhttp://weather.noaa.gov/weather/metar.shtml
METAR, TAF, PIREP, AIRMET, SIGNMET, NOTAM, Forecast area, decoded with more info - 4-character ICAO codes requiredhttp://www.wunderground.com/Aviation/index.html
Aviation Digital Data Service (ADDS), full weather info for multiple locations (separate ICAO IDs with a space)http://aviationweather.gov/adds/tafs/
Time and distance calculations - great circle distance, should only be used as a guide
, includes a 15 minute bias on takeoffhttp://www.airrouting.com/content/TimeDistanceForm.aspx
Weather METARs for any station in the world:http://weather.noaa.gov/weather/current/XXXX.html
(where XXXX is the 4-letter ICAO code).
eg: Barbados ishttp://weather.noaa.gov/weather/current/TBPB.html
And/or... send an email to email@example.com
and place the 4 letter designator in the SUBJECT field (eg. TJSJ). For multiple locations, simply separate the ICAO identifiers with a space (eg. TJSJ TAPA TBPB). They will email back the latest METAR/s and TAF/s. Works great for Smartphones.