October 2016 was cold

Photo of the bark of a Eucalyptus tree

White Box at Sunset

In this month, each of five sunny spells of normal temperature was followed by a cold, cloudy, humid break, generally with rain. Only a few days were warmer than normal, including the 27th. That was the first 30° day of the season, five weeks late.
The average weekly temperature was persistently three or four degrees cooler than normal. One cold week about the 15th was more than five degrees below normal, and the warmest week, about the 29th, was still half a degree low.
Most nights were very cool. I recorded no frosts, but others may have done. My most recent frost was early in September.
There were six rain days, not counting two readings of 0.2 mm. The highest reading was 20.0 mm on the 23rd.

Weather log for October 2016

Comparing October months

This was the coldest October on this record from 1999. That includes not only the maximum, mean, and minimum air temperatures read in the Gill Screen, but also the subsoil temperature at 750 mm. Noting that October 2015 had the highest October temperatures, the sudden collapse is astonishing. Last October was three degrees warmer than normal; this month was almost three degrees colder than normal. Put another way, the seasonal warming is a month late this year and was a month early last year.
Unlike September, there was not an unusual amount of moisture in October. Humidity, cloudiness and daily temperature range were near normal.
The monthly rainfall total of 72.1 mm was above the average of 58 mm, in the 70th percentile.
I have discussed the current drought status (that is, drought-free) in another post.

Climate for October 2016


Data. Rainfall figures are usually from the automatic rain gauge at Manilla, published on the internet by the Bureau of Meteorology as Station 55031. However, the gauge ceased recording on the 8th of October, and later readings are from my non-standard gauge. All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

September 2016 had near-record rain

Blooms of Acacia paradoxa

Kangaroo Thorn

There were fourteen rainy days in a month that ended no warmer than it began. The month of September normally warms up by nearly four degrees. This time it remained near 14° all month. Some plants encouraged by the plentiful moisture were discouraged by the cold.
The highest daily rainfall reading, 28.8 mm on the 14th, hardly compares with one of 71.1 mm in 2005, or even one of 40.0 mm in 2011.
No days were warm. For the first time in this 18-year record, no September day reached 25°. More days than ever (18) were below 20° but not one was as low as 15°. Temperatures at night were near normal. A frost on the 5th was the only one. It may have been the last of the year, about a fortnight earlier than usual.
Only four mornings this month had no cloud, while seven were totally overcast.

Weather log for September 2016

Comparing September months

For monthly average temperatures, the daily maximum of 19.7° stands out as a record low, 4.1° below normal. Three indicators for moisture reached their extreme September values for the new century: rainfall, percentage of cloudy mornings (63%), and (narrowest) daily temperature range (12.0°). Dew point (6.0°) was just above normal, but very much higher than in September months since 2010.
The monthly rainfall total of 122.4 mm (amended) was one of the four highest ever September readings. The others were: 1917: 124 mm; 1949: 126 mm; 1998: 166 mm.
There are not now any noteworthy shortages in rainfall totals for any number of months, up to 360 months (thirty years).

Climate for September 2016


Data. Rainfall figures for this month are from the automatic rain gauge at Manilla, published on the internet by the Bureau of Meteorology as Station 55031. All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

Extremely wet winter 2016

Water flowing over a weir

Manilla Weir Fish Ladder

This winter, with 227.4 mm of rain, was the fifth wettest in the record from 1883. In order of rainfall, wetter winters were: 1920 (318 mm), 1998 (304 mm), 1950 (261 mm) and 1952 (233 mm). This winter’s total was more than 100 mm over the average (125 mm). The heaviest daily fall, 37 mm, was on 5 June, and there were four other falls of more than 15 mm; two in June and two in August.
There were big week-long swings in temperature through June and July. On four occasions nights were more than four degrees warmer than normal and on one occasion days were four degrees cooler than normal. No such swings occurred from late July to mid-August, then days became five degrees cooler than normal. In this winter, there were few spells of either hot days or cold nights. The number of frosts (42) was near the usual number (44).

Graphical log for winter 2016
While the mean temperature of the season was normal, most other measures of climate were not.
The winter seasons of 2016 and 2010 were both extremely moist. Winter 2016 had more rain (227 mm versus 160 mm) and more cloudy days (53% versus 49%). In other respects 2010 was more moist: the dew point was higher (3.7° versus 2.5°), and the days had a narrower temperature range (12.5° versus 12.8°). The daily temperature range for winter is usually much wider: 15.3°. It was 17.5° in winter 2002!

Climate for winter 2016


Rainfall figures for this month are from the automatic rain gauge at Manilla, published on the internet by the Bureau of Meteorology as Station 55031. All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

Wet August 2016 had two cold days

Photo of knife-leaf wattle blooms

Knife-leaf Wattle

Six days with at least eight millimetres of rain made for a very wet August.
On the average, the temperature was normal until the fourth week, which was cool. However, there were two remarkably cold days. The 3rd, at 10.6°, was the second coldest August day and the 22nd, at 11.6°, the fifth coldest. Most nights were cool, around 1°, but several were much warmer, generally with the rain. Most days were sunny, and eighteen of the mornings were frosty, about three more than usual.

Weather log for August 2016

Comparing August months

On average, the days were cold: as cold as in August 2001, but not as cold as in 2008 or 2010. The average night-time temperature, however, was normal. The dew point, while not high, was higher than in the previous four August months.
The monthly rainfall total of 80.2 mm was twice the average (40 mm), and in the 89th percentile. No rainfall total for any number of months is now below the 19th percentile. That is the 42-month total of 1949 mm, which is a mere 313 mm lower than the median 42-month value. Both Greenhatch Creek and Rushes Creek have flowed in recent weeks.

Climate for August 2016


Data. Rainfall figures for this month are from the automatic rain gauge at Manilla, published on the internet by the Bureau of Meteorology as Station 55031. All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

July 2016 had a record warm night

Photo of a pond at sunset

A neighbour’s dam

The second cloudiest month of this century brought the warmest July night.
There were two very warm spells in the trace of weekly average temperature. Both were due mainly to warm nights. The second spell, coming in the third week, reached nearly six degrees above normal. On the morning of Saturday the 23rd, the minimum reading on the screen thermometer, 14.4°, was the highest July minimum in the record from 1999.
Up to the 25th, the weather was changeable, with some days overcast and rainy, and others fine and sunny. A very warm sunny day on the 17th, following a frost, had the unusually wide daily temperature range of 21.9°. From the 25th, the weather settled to what is normal for July. In the whole month, there were sixteen frosts, which is normal.
The highest rainfall reading was only 11.4 mm. Ten days had rainfall recorded, but three of these had 0.2 mm, on days when rain was not seen.

Weather log for July 2016

Comparing July months

The mean daily maximum temperature (16.9°) was normal. The mean daily minimum temperature (4.0°) was two degrees above normal, making the average temperature (10.5°) one degree above normal. Similarly, the subsoil temperature (14.7°) was one degree above normal.
The daily temperature range, normally 15.0°, was 12.9°, not quite as narrow as in 2010 (12.3°). The early morning dew point was normal. At 2.2°, it was so close the the daily minimum temperature (4.0°) that fogs were to be expected.
The month was extraordinarily cloudy. Cloud cover is assessed by the number of octas (eighths) of the sky seen to be covered by cloud at 9 am. I compare cloudiness of months by the percentage of “cloudy mornings”: those when I see more than four octas of cloud. This month, with 21 cloudy mornings, had 68%. July normally has only 35%. The only month in this century with a higher value was June 2013, with 73%.
The monthly rainfall total of 32.4 mm is below the average (41 mm), in the 47th percentile. The greatest rainfall “shortage” is now in the 48-month total (2221 mm) which is in the 14th percentile. Both Greenhatch Creek and Rushes Creek are just flowing.

Climate for July 2016.


Data. Rainfall figures for this month are from the automatic rain gauge at Manilla, published on the internet by the Bureau of Meteorology as Station 55031. All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.