2015 – A reflection on ‘The Year that Was’

Climate and Weather Matters

The monsoon trough developed across northern Australia on 21st December bringing with it the increased risk of a tropical cyclone forming. The low pressure system became a Category One Cyclone for a short time in the Gulf of Carpentaria before making landfall and becoming a rain depression causing major flooding in many areas. It also brought relief to many drought ridden areas.

December has seen the first significant heatwave for the summer season, as extreme heatwave conditions covered large parts of southern Australia. An extremely hot air mass saw Adelaide to equal its 2007 record for three consecutive 40 degree days in December. As to be expected, severe and extreme heatwaves pose significant risks to human health and safety, particularly the elderly, who are more vulnerable to the effects of heat stress. When temperatures are unusually hot over a period of time, with continuously high night-time and day-time temperatures, heat stress becomes a critical factor in human survival and infrastructure resilience..

At the end of the month, a broad area of low pressure over the interior and southern Australia generated an extensive cloudband with embedded thunderstorms. Moderate to heavy rainfall extended from central Australia into, northern districts of South Australia and into south-eastern Australia.

Down the east coast and on the Ranges we experienced the El Niño effect with 1/3 of the

average rainfall bringing the total 2015 annual rainfall to match the 120 year average.

 

2015 Maleny Climate – Month by Month

 

January – Dominate feature was a strong monsoonal trough extending over Cape York across Australia to Broome. Maleny’s rainfall was 292mm, representing 6.7 mm over the 120 year norm.. The mean temperature was 4.5 degrees below average

 

February – TC “OLA” in the Coral Sea tracked toward the Queensland Coast , decreasing in intensity as it moved in a southerly direction to become a rain depression. The monsoonal trough drifted  north out of Australia.. The month’s rainfall was 602mm, which is 282 mm

above the norm. The mean temperature was 4.8 degrees below norm. On the 16th at 2.00am there was an earthquake of 5.2 magnitude felt at Rockhampton.

 

March – The dominate feature in the first part of the month was a northwest cloudband with a belt of rain extending down to NSW. Total rainfall was 36.7mm , representing 252 mm below average. The mean maximum 27.5ºC, was two degrees above the norm, and mean minimum was also two degrees above norm

On 14th TC “NATHAN” in the monsoonal trough formed up in the Coral Sea and headed on a SE course towards the Queensland coast. The TC made land on Cape York and became a rain depression

 

April – The month’s weather was dominated by a high in The Bight covering the whole continent extending a ridge up the east coast. In the first few days gale force winds and torrential rain of 168 mm were recorded..The total rainfall was 224 mm, representing 30 mm above the norm. Both the Minimum and maximum temperatures represented the all year’s average. Sunshine hours and Evaporation also recorded the mean for the month.

 

May – For the whole month the High in the Bight hovered to and fro, covering the continent and influencing Australia’s climate. Rainfall was 123 mm above the average, The Mean Minimum was one degree above the norm and the Mean maximum recorded the norm.

 

June – It was two degrees warmer for the first month of winter, whilst the Mean Daily Maximum remained. on the norm..The month’s total rainfall was 23 mm below average..

The colourful sunset on Tuesday 2nd captured the attention of many Maleny weatherwatchers and I was asked what caused such a wonderful spectacle to happen. The phenomenon usually occurs in the winter months when stable weather conditions prevail, such as when we are are under the influence of a high pressure system with light winds and altostratus clouds streaking low in the western sky. Often present is a prominence of pollution in the atmosphere in the form of dust or sand blown in from deserts   The pollution in this case was from back burning, as there was little or no wind for dispersal as it was held down by temperature inversion. The setting sun with rays of light through any of the above medium will cause refraction in the atmosphere, visible to the naked eye as colours ranging from yellow to orange to red.

 

July – The month’s ‘mean minimum temperature was one degree up on the norm and the mean maximum was down by the same amount. Precipitation was 61 mm below average. The synoptic charts for the first half of the month showed a large high pressure system centred over central Australia. This system finally moved east into the Tasman Sea on the 20th of the month, followed by a another system swiftly moving into Australia from the Indian Ocean.. Did you feel the earth shake on Thursday July 30th at 9.41am when a earthquake with a magnitude of 5.3 was recorded 100km off Fraser Island in the Coral Sea.

 

August Another earthquake occurred on Saturday 1st at 1.30 pm with a magnitude of 5.7

236km northeast of Brisbane., followed by two significant aftershocks 90 minutes later with magnigtu9des of 5.1 and 3.1 respectively.

 

There was very little rainfall until near the end of the month and it would have been classified a ‘dry’ month had there not been a storm on the last day when we recorded an inch of rain. This amount, with the odd shower or two  recorded in the latter half of the month, brought the total for the month to 73.4 mm, representing 10 mm above the average over  110 years.

With the El Niño stronger and with the forecast it will be as strong as the 1997/98 episode it  is more than likely we will have a few drier months ahead. In 1997 the El Niño started in June and continued until October 1998 – seventeen months with below average rainfalls. An official drought was declared in many parts of Queensland but we were lucky as on the Ranges we enjoyed a few maritime showers.

 

September –

The synoptic situation in the first week of spring was complicated  by a small high in the Tasman Sea rapidly moving east, a cold front moving rapidly east over  western Australia and a trough extending from the gulf down to northern NSW. This left stable atmosphere over Queensland’s  east coast. resulted in a daily dew point  of 0.2mm and  a maximum daily temperature  a half a degree above the norm. Moist winds over our shoreline  brought showers adding up to over 8.0mm.  Similar conditions prevailed in the third week with maritime showers adding up to 25mm.

A dry following week in the final stages of being a dry stable month, before a synoptic change brought a kerfuffle of high and surface troughs combining  over east Queensland resulting in some fierce thunderstorms with hail. Total rainfall for the month was 60.2mm, three millimetres under the 120 years average.

 

October – The second month of spring – was not a dry month as traditionallly expected, and precipitation was  recorded on most days.Total rainfall  was 25mm above the 123 year average. In between the showers the sun shone for 170 hours on solar panels.The highest October rainfall  was in 2010 with  532 mm.   The synopic chart for the first week of the month  showed four high pressure cells through the Bight and southern states, with a ridge of high pressure extending up the east coast. A surface trough from the Gulf down to Victoria was active for a few hours on the first day and was responsible for a depression setling in over the Ranges, and in Maleny we recorded  24 mm of heavy rain`with hail.. The depression soon dissipated as a stable high pressure system moved in.  The inclement weather soon cleared and was followed by stable conditions as high pressure systems dominated. The result was sunshine and heavy morning dews.  Stable atmosphere prevailed over the next few weeks.  It was windy on 8th and 9th with maximum gusts of 35km/hr. Thunder was  heard on four occasions.

 

November   Heatwaves with record temperatures have been recorded in several states. It is timely to say something about the dangers associated with powerful rays from the sun..

rays can cause numerous health problems, such as sun burn, skin cancer, skin aging, and cataracts, and can suppress the immune system

The strength of the sun’s ultraviolet (UV) radiation is expressed as a ‘Solar UV Index’, a system developed by the World Health Organization. These Met Office forecasts include the effects of:

  • the position of the sun in the sky;
  • forecast cloud cover;
  • ozone amounts in the stratosphere.

 

The strength of the sun’s ultraviolet (UV) radiation is expressed as a ‘Solar UV Index’, a system developed by the World Health Organization. These Met Office forecasts include the effects of:

  • the position of the sun in the sky;
  • forecast cloud cove
  • ozone amounts in the stratosphere

Energy from the sun reaches the earth as visible, infrared, and ultraviolet (UV) rays. Exposure to UV

Weekly sea surface temperatures

Compared to two weeks ago, warm sea surface temperature (SST) anomalies have increased in parts of the eastern equatorial Pacific and decreased across the northeast of the basin and over the western equatorial Pacific (west of the

December – The mini- heatwave in the month increased   the mean daily maximum temperature by five degrees. The annual rainfall departure from norm was 132mm.

The synoptic chart for the month show a series of rapid moving low and high pressure systems crossing the country. Associated surface troughs and hot winds from high pressure systems presented the right conditions for a heatwave of abnormal proportions.. The hot weather descended on Adelaide and surrounding areas on 19/20 th. The temperature reached 40 °C in Adelaide on each of the four days from 16–19 December. This was the first occasion that four consecutive days of 40 °C or above had occurred in Adelaide in December: runs of three consecutive days of 40 °C or above had previously occurred from 29−31 December 2007, 28−30 December 1898 and 28−30 December 1897.

December 2015 Summary

 

The monsoon trough developed across northern Australia on 21st December bringing with it the increased risk of a tropical cyclone forming. The low pressure system became a Category One Cyclone for a short time in the Gulf of Carpentaria before making landfall and becoming a rain depression causing major flooding in many areas. It also brought relief to many drought ridden areas.

December has seen the first significant heatwave for the summer season, as extreme heatwave conditions covered large parts of southern Australia. An extremely hot air mass seen Adelaide to equal its 2007 record for three consecutive 40 degree days in December. As to be expected, severe and extreme heatwaves pose significant risks to human health and safety, particularly the elderly, who are more vulnerable to the effects of heat stress. When temperatures are unusually hot over a period of time, with continuously high night-time and day-time temperatures, heat stress becomes a critical factor in human survival and infrastructure resilience..

At the end of the month, a broad area of low pressure over the interior and southern Australia generated an extensive cloudband with embedded thunderstorms. Moderate to heavy rainfall extended from central Australia into, northern districts of South Australia and into south-eastern Australia.

Down the east coast and on the Ranges we experienced the El Niño effect with 1/3 of the

average rainfall bringing the total 2015 annual rainfall to match the 120 year average.

climate 012016

Maleny Annual Rain 2014/15

Annual Rain 2015

MERRY CHRISTMAS and a HEALTHY & HAPPY NEW YEAR

TO ALL OUR WEATHER WATCHERS A BIG THANK YOU FOR ALL YOUR

LOYAL  SUPPORT OVER THE PAST YEAR

KAY & PATRICK

Climate Influences

Climatces  Influences

El Niño expected to decrease early in 2016

A strong El Niño persists in the tropical Pacific Ocean. The event is comparable to the record events of 1997–98 and 1982–83. International climate models suggest that El Niño SSTs are approaching their peak, and will decrease in the first quarter of 2016. With such warm SSTs, models suggest the tropical Pacific is unlikely to return to neutral until at least autumn 2016, although impacts on Australian climate are likely to decline prior to this.

El Niño’s influence on Australian rainfall is variable at this time of year, with both wetter and drier summers observed in past events depending on how quickly the event breaks down. However, on average an El Niño summer brings below-average rainfall across northern Queensland, and a slight drying influence across the southeast of Australia. Conversely, inland Western Australia often sees above-average rainfall at this time of year during El Niño.

El Niño is as strong as previous episodes

A strong El Niño persists in the tropical Pacific Ocean. The event is comparable to the record events of 1997–98 and 1982–83. International climate models suggest that El Niño SSTs are approaching their peak, and will decrease in the first quarter of 2016. With such warm SSTs, models suggest the tropical Pacific is unlikely to return to neutral until at least autumn 2016, although impacts on Australian climate are likely to decline prior to this.

El Niño’s influence on Australian rainfall is variable at this time of year, with both wetter and drier summers observed in past events depending on how quickly the event breaks down. However, on average an El Niño summer brings below-average rainfall across northern Queensland, and a slight drying influence across the southeast of Australia. Conversely, inland Western Australia often sees above-average rainfall at this time of year dur

November Mini-heatwave

Energy from the sun reaches the earth as visible, infrared, and ultraviolet (UV) rays. Exposure to UV rays can cause numerous health problems, such as sun burn, skin cancer, skin aging, and cataracts, and can suppress the immune system

The strength of the sun’s ultraviolet (UV) radiation is expressed as a ‘Solar UV Index’, a system developed by the World Health Organization. These Met Office forecasts include the effects of:

  • the position of the sun in the sky;
  • forecast cloud cover;
  • ozone amounts in the stratosphere.

The chart  gives an indication  of the effect UV rays has  on different skin types  sunbathing without protection Heatwave Weather

October Weather Summary 2015

October – the second month of spring – was not a dry month as traditionallly expected, and precipitation was  recorded on most days. Total rainfall  was 25mm above the 123 year average. In between the showers the sun shone for 170 hours on solar panels.The highest October rainfall  was in 2010 with  532 mm.

The synopic chart for the first week of the month showed four high pressure cells through the Bight and southern states, with a ridge of high pressure extending up the east coast. A surface trough from the Gulf down to Victoria was active for a few hours on the first day and was responsible for a depression setling in over the Ranges. In Maleny we recorded  24 mm of heavy rain`with hail.. The depression soon dissipated as a stable high pressure system moved in.  The inclement weather soon cleared and was followed by stable conditions as thigh pressure systems dominated. The result was sunshine and heavy morning dews

Stable atmosphere prevailed over the next few weeks. It was windy on the 8th and 9th with maximum gusts of 35km/hr. Thunder was  heard on four occasions.