Skip to main content
Hong Kong Observatory Brand Hong Kong - Asia's world city
GovHK Traditional Chinese Simplified Chinese Search
Search Site Map Contact Us
red dot
Print Version
Back
Print Version PDF Version

Backward Trajectory Map in April 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 April 2011 is now available on the following webpage:

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

As indicated in the figure below, the air masses reaching Hong Kong in April 2011 mainly originated from northeast of Hong Kong as the territory was under the influence of the northeast monsoon most of the time. With Hong Kong transitting to spring, some air masses of maritime origin also affected Hong Kong.


Backward Trajectory of Air Mass reaching Hong Kong in April 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

 

Last revision date: <21 Dec 2012>