A sudden onset of strong winds with speeds increasing to at least 16 knots (18 miles per hour) and sustained at 22 or more knots (25 miles per hour) for at least one minute. The intensity and duration is longer than that of a gust. It is reported as "SQ" in an observation and on the METAR.
Meaning of SQUALL in English
Weather and meteorology English vocabulary. Английский словарь погоды и метеорологии . 2012