BAMOS March 2017
18
Article
Recent severe weather events in the Australian Capital Territory
Gavin O ’ Brien , Southside Weather Watch ( ACT ) southsidewhract @ gmail . com
I operate a Personal Weather Station ( PWS ) which is a Davis Vintage Pro 2 with sensors communicating by wireless link to a Console on my office . In addition , I also operate a manual weather station with a temperature screen modelled on the conventional Stevenson Screen and Marquis rain gauge located on a grassed plot on the upper level of our back garden . A Maximum Analog Dial Anemometer is co-located with the Davis Anemometer , attached to the top of a guyed mast whose base is anchored on the upper end of the rear veranda roof . The sensors are about nine metres above ground level . The sensors have a good exposure in all directions , except the sector from east through north east as we are located on the southwest slope of Gilmore Hill whose summit , about 15 metres higher than the site , is located about 350 metres to the east north east . There is a mercury barometer adjacent to my office . It is set to station level readings ( 662 metres above mean sea level ).
Observations are made at 0900 and 1500 local time daily , with special observations when unusual or severe weather occur . The PWS transmits data to a data logger set at five minute intervals , which in turn transmits the information to a personal computer . The data are sent via the internet to the Weather Underground web site in real time , with the station name “ Gilmore North ”. Manual observations are entered into the UK Met Office WOW website operated by the Bureau of Meteorology , twice daily following the observations . A Meteorological Log for the 0900 and 1500 Observations are kept as paper copy and filed . I am a Storm Spotter for the Bureau of Meteorology .
Severe Thunderstorm and hail storm in the Tuggeranong Valley ACT 29 January 2016 .
Synoptic Situation The Synoptic Analysis for 11:00 a . m . 29 January 2016 ( 0000 UTC )
Figure 1 ( above ). Mean sea level pressure conditions over Australia , 0000UTC 29 January 2016 . Figure 2 ( below ). Loop of 850hPa , 500hPa and 250 hPa conditions over Australia , 0000UTC 29 January 2016 . Images : Australian Bureau of Meteorology .
A trough extended from north west Queensland through central New South Wales to a low pressure system , 1002 hPa located over central Bass Strait , separating warm moist tropical air flowing southward around a 1023 hPa high system . This system was centred over the southern Tasman Sea , while another high