SJU controller; absent tower wind equipment; elected to estimate wind information based upon the wind sock; noting the flight crew advised the velocity reported was inaccurate based upon aircraft equipment.

Narrative

While I was working the Local position; Air Carrier X requested a wind check on final for Runway 10. Since the Tower doesn't have a wind measuring equipment and the wind information was more than 20 minutes old from the last METAR observation; I observed the wind sock that was adjacent to Runway 10 and gave the pilot an estimated wind reading of 110 at 10 knots in which I missed that there was a significant wind gust present. The Pilot informed me in an apparent disgusted manner that his/her flight computer was showing a wind of 24 knots on final contrary to my estimation. The aircraft landed without any further incident. There is no wind measuring equipment; ATIS or ASOS equipment available at the Tower. Recommendation; since there is no Wind Measuring Equipment available and this; I consider is an unusual circumstance (not having Wind Measuring Equipment for a prolonged time) refresher training should be given to controllers regarding unusual operations such as this. Also; a monthly team briefing with our FLM (Front Line Manager) will help to clarify any doubts that develop during the month. Also; there is a lack of a clear and concise policy on what other procedures are we allowed to use (using wind sock; etc) when giving estimated winds when in our opinion the METAR data is outdated. On a personal side; I am reviewing the 7110.65 and reviewing all the chapters regarding issuing wind and ATIS (lack of) information. Also; I have requested my FLM to provide me a definite answer in regarding whether we can use the wind sock as a reference or not since I am concerned this technique might be used in the future by other controllers at my facility.