Weather for the weekend of 10 - 11 December 2011

 Updated 9/12/2011

A high south east of the continent is moving slowly towards New Zealand whilst another approaches the south west of the continent, ridging into the Bight. Slack pressure with associated troughs will dominate the continent through the weekend into the early part of next week. The surface/mid level disturbance that brought the recent rain is now off the coast. However, instability associated with the slack pressure and troughs will bring thundery weather to the Downs through the weekend before clearing late on Monday. NOAA is currently forecasting a further 40-50mm of rain for this period. With the CAPE around 1000J/kg and SLI at -4C to -5C, there will be thunderstorms on both days and these could be severe.

In the last seven days, Dalby has received 37mm of rain and Oakey 17mm,. Further west, the heavy rain passed over Roma (85mm) awith its eastern boundary at Dulacca (32mm).

Saturday 10 December 2011
Dalby             27C
Stability          B
Convection      Dry convection to 6,000ft with cloud base at 5,000ft
Wind              NW @ 10kts

High cloud will increase during the day.



Sunday 11 December 2011
Dalby              30C
Stability          A
Convection      Dry convection to 8,000ft with cloud base at 6,000ft
Wind              NW @ 10kts

High and medium cloud cover will be fairly solid throughout the day.


Looking ahead for the Juniors (at Kingaroy) and Caboolture week (at DDSC)

The meteorogram for the next seven days is below. It shows the major thunderstorm activity and rain clearing from the Downs late on Monday, with Tuesday and Wednesday looking promising, despite the possibility of showers. Thursday is showing significant rain at this stage, but that is a bit distant for reliable forecasting (the forecast is clearly moving around quite bit).

Weather for the weekend of 3 - 4 December 2011

A large and strong (reaching 1033 hPa) high is practically stationary in the Bight. It will move only very slowly east of the next few days but will ridge up the east coast behind the trough that is producing rain in the eastern Downs early today. This trough has produced 48mm of rain at Roma in the last 24 hours but falls appear to be diminishing as it moves east (Miles received only 2.8 mm). The trough will cross the coast today. A further trough is forming south from the Gulf, but will be held behind the coastal ridge until after the weekend.

Although Dalby received only about 30mm of rain last week, the area around Chinchilla was much wetter (falls of 50 - 60mm). Depending on the rain from the current trough, it can be expected that the area around Chinchilla will remain somewhat wet, with suppressed convection. NOAA is forecasting about 8mm as the trough passes.

Saturday December 3 2011
Dalby            28C
Stability         A
Convection     Dry convection to 10,000ft with cloud base at 8,500ft
Wind             E @ 5 kts

High cloud will from from around midday, thickening as the day progresses.


Sunday December 4 2011
Dalby            28C
Stability         B
Convection     Dry convection to 9,500ft with cloud base at 8,000ft
Wind             SE @ 5 kts

There will be significant high cloud throughout the day.