Maleny Weather

November this year was the driest month for 17 years with only 37mm over five rain-days. This was 26 per cent below the 118-year average of 139mm.

The synoptic weather pattern was similar to 2006 with NW cloud bands and southern cold fronts bringing storms and structural damage to southern states. The NW cloudbands that is normally responsible for the hinterland’s three-day rain spell have this month avoided SE Queensland and moved further west and south.

The weather pattern for most of the month featured a high pressure system in the northern Tasman Sea. This brought many days of hot dry northerly air streams to the hinterland, giving both maximum and minimum temperatures a two degrees boost over the norm of 24.8°C and 15.8°C respectively.

 La Niña is still active but considerably weaker than the very strong 2010-11 event.

This halo phenomenon photo was taken by Jemma Mays from Maleny Showground on Saturday morning Nov 26 – one of many people looking skyward watching this wonderful picture of nature enfolding in cirrus cloud.  This is created by ice crystals in the cloud refracting light by an angle of 22 degrees with an inner edge of a reddish tinge. The space between halo and sun appearing darker than just outside the halo. People seeing this halo for the first time are often surprised at how much larger it appears compared with photographs. The distance from the sun to the edge of the ring is equivalent to the outstretched span of a hand held up at arm’s length.

A thunderstorm at 4 pm on Wednesday brought the 21-day ‘dry spell’ to an end. This was the result of a slow moving surface trough arriving over the ranges from the west. Rainfall was minimal and did little to fill near empty hinterland rain tanks.

However, on the following day the region had a fringe benefit from an upper level cloudband extending from Broome to Victoria. Most of the rain fell in northern NSW but the ranges had some moderate intermittent rain showers with over an inch recorded in most districts. The dry ground soaked up much needed moisture and helped replenished rural water tanks.

Total rainfall so far this month is 37mm and represents the lowest November rainfall since 1994 when Maleny recorded 30mm.  The driest November recorded in 118 years was in 1913 with 8mm

Minimum temperature for the week was on Tuesday at 4am with 19°C and the maximum was 32°C on Sunday at 10.45am with a stress factor of 38°C. Sunday was also a trigger-day for people sensitive to weather change.

The Bureau of Meteorology reports La Niña conditions have undergone little change over the past fortnight, with most atmospheric and oceanic indicators remaining at, or just exceeding La Niña thresholds. Climate models surveyed by the Bureau suggest this event is likely to peak near the end of the year and persist into early 2012. Current observations of this La Niña show that it is considerably weaker than the very strong 2010-11 event.

A ridge of high pressure along the east coast brought a dry hot northerly air flow to the Ranges. Temperatures peaked on Tuesday 15^th at 1.00pm with 31°C and a heat stress factor of 39°C.

The dry spell continues with 19 consecutive rain-free days. The lowest Maleny November rainfall was recorded in 1913 with 7.8mm. Our November rainfall to date is 4.8mm. There is a likelihood the drought will be broken this week with rain forecasted on Thursday.

BOM manager of climate prediction services Dr Andrew Watkins says temperatures in the Pacific Ocean during last  year’s strong La Niña were about 1.5 degrees cooler than normal, while this year they are only 0.8 degrees cooler, leading to a relatively weak La Niña. He says at this time last year, ocean temperatures in the north of Australia were at record levels but this year they are close to average.

A La Niña episode usually means an above average rainfall in the summer months but the strength of an episode is normally an indication of how much extra rain is expected.

It has been another very ‘dry’ week on the ranges. The synoptic weather pattern is beginning to look similar to 2006 with NW cloud bands and southern cold fronts bringing storms and structural damage to southern states. The NW cloudband that is normally responsible for the range’s three-day rain spell has avoided SE Queensland and moved further west and south.

Throughout the week the high in the Tasman Sea has dominated the weather bringing strong north-easterly winds and cloud cover to the hinterland.

Minimum temperature was 13.8°C on Monday 7^{th _} two degrees above the norm and Maximum 29.5°C on Thursday 10^th representing five degrees over the norm.

Despite the dryness of the ground there is a blaze of colour from the Jacaranda trees in full bloom. The rain forecasted for the weekend did not eventuate.