Aviation Digital Data Service (ADDS)

Output produced by TAFs form (2125 UTC 24 January 2017)
found at http://www.aviationweather.gov/adds/tafs/
 
Forecast for: EGLL (LONDON/HEATHROW , GB)
Text: TAF EGLL 241656Z 2418/2524 23003KT 9999 FEW040
Forecast period: 1800 UTC 24 January 2017 to 0000 UTC 26 January 2017
Forecast type: FROM: standard forecast or significant change
Winds: from the SW (230 degrees) at 3 MPH (3 knots; 1.6 m/s)
Visibility: 6 or more miles (10+ km)
Clouds: few clouds at 4000 feet AGL
Weather: no significant weather forecast for this period
Text: BECMG 2418/2421 3000 BR
Forecast period: 1800 UTC 24 January 2017 to 0200 UTC 25 January 2017
Forecast type: BECOMING: Conditions expected to become as follows by 2100 UTC 24 January 2017
Winds: from the SW (230 degrees) at 3 MPH (3 knots; 1.6 m/s)
Visibility: 1.86 miles (2.99 km)
Clouds: few clouds at 4000 feet AGL
Weather: BR  (mist)
Text: PROB40
Forecast period: 2000 UTC 24 January 2017 to 0200 UTC 25 January 2017
Forecast type: TEMPORARY: The following changes expected for less than half the time period
Visibility: 0.12 miles (0.19 km)
Weather: FG FZFG  (fog, freezing fog could not decipher "FZ")
Text: TEMPO 2420/2502 0200 FG FZFG VV///
Forecast period: 0200 to 0900 UTC 25 January 2017
Forecast type: BECOMING: Conditions expected to become as follows by 0500 UTC 25 January 2017
Winds: from the SW (230 degrees) at 3 MPH (3 knots; 1.6 m/s)
Visibility: 0.12 miles (0.19 km)
Clouds: few clouds at 4000 feet AGL
Weather: FZFG FG  (freezing fog, fog)
Text: BECMG 2502/2505 0200 FZFG FG VV///
Forecast period: 0900 to 1200 UTC 25 January 2017
Forecast type: BECOMING: Conditions expected to become as follows by 1200 UTC 25 January 2017
Winds: from the SW (230 degrees) at 3 MPH (3 knots; 1.6 m/s)
Visibility: 4 miles (6 km)
Ceiling: 800 feet AGL
Clouds: broken clouds at 800 feet AGL
Weather: NSW  (no significant weather)
Text: BECMG 2509/2512 6000 NSW BKN008
Forecast period: 1200 UTC 25 January 2017 to 0000 UTC 26 January 2017
Forecast type: BECOMING: Conditions expected to become as follows by 1500 UTC 25 January 2017
Winds: from the SW (230 degrees) at 3 MPH (3 knots; 1.6 m/s)
Visibility: 6 or more miles (10+ km)
Ceiling: 1200 feet AGL
Clouds: broken clouds at 1200 feet AGL
Weather: NSW  (no significant weather)
Text: BECMG 2512/2515 9999 BKN012
Forecast period: 1500 UTC 25 January 2017 to 0000 UTC 26 January 2017
Forecast type: TEMPORARY: The following changes expected for less than half the time period
Ceiling: 1800 feet AGL
Clouds: broken clouds at 1800 feet AGL
Weather: no significant weather forecast for this period