Backward Trajectory Map in June 2011

By using computer model analyses, the past 72-hour backward trajectory of the air mass reaching Hong Kong is estimated by the Observatory on a daily basis. The daily trajectories are compiled into the Monthly Backward Trajectory Map. The Monthly Map for June 2011 is now available on the following webpage:

http://www.weather.gov.hk/wxinfo/trajectory/trajectoryMonthly_e.shtml

In June 2011, most of the air masses reaching Hong Kong originated from the south, indicating that the territory was mainly under the influence of southerly airstreams.

Backward Trajectory of Air Mass reaching Hong Kong in June 2011

For Daily or Seasonal Backward Trajectory Maps, please visit the following webpages:

Daily Backward Trajectory Map
http://www.weather.gov.hk/wxinfo/trajectory/trajectory_e.shtml

Seasonal Backward Trajectory Map
http://www.weather.gov.hk/wxinfo/trajectory/trajectorySeasonal_e.shtml