December 2015: normal month, normal year

Senna bush photo

Senna-leaf circles

Very few days or nights were more than four degrees from normal this month. The coldest day (the 23rd) was 24.9°, only 7.6° below normal.
Rain fell, mainly as showers, on nine days spaced through the month. The highest reading was 31 mm on the 10th.

Weather log December 2015

 Comparing December months

Nearly all climate variables were very close to normal. Those furthest from normal were:
Early morning dew point, 9.4°, below normal by 3.9°;
Daily minimum temperature, 17.1°, above normal by 0.7°;
Cloudy days percent, 45%, above normal by 14%.
The total rainfall of 101.9 mm was well above the average of 74 mm. It was almost the same as in last December (99 mm): in the 74th percentile, The two-month total for November and December was also high (176 mm). There are no serious rainfall shortages for totals for any number of months.

Climate for December 2015

The Year 2015

Compared to other years in the new century, this year had day temperatures that were on the average (25.6°), and nights (10.8°) that were just 0.6° above average. The subsoil temperature (20.1°) was also near average.
Like last year, the percentage of mornings with more than four octas of cloud (37%) was close to the recent average (40%) for 2007 to 2014, but much more cloudy than the earlier average (26%) for 2000 to 2006.
The rainfall, 621 mm, was only 31 mm below the long-term rainfall average of 652 mm.


Data. All data, including subsoil at 750 mm, are from 3 Monash Street, Manilla. Rainfall data up to 26/3/15 is from Manilla Post Office, Station 055031.

3-year trends to December 2015

Parametric plots of smoothed climate variables at Manilla
“December 2015: moist”

Trends to December 2015

December raw anomaly data (orange)

In December, raw values for daily maximum and daily minimum temperature anomaly, which had been very high in October and November, returned to normal. Rainfall and cloud became higher than normal.

 Fully smoothed data (red)

In the latest month with fully smoothed data (June 2015) no anomalies were changing much. Most were near cool/moist climate peaks (towards the lower left): only daily minimum temperature and subsoil temperature were near warm/dry peaks. None of these peaks had extreme values.


Note:

Fully smoothed data – Gaussian smoothing with half-width 6 months – are plotted in red, partly smoothed data uncoloured, and raw data for the last data point in orange. January data points are marked by squares.
Blue diamonds and the dashed blue rectangle show the extreme values in the fully smoothed data record since September 1999.

Normal values are based on averages for the decade from March 1999.* They appear on these graphs as a turquoise (turquoise) circle at the origin (0,0). A range of anomalies called “normal” is shown by a dashed rectangle in aqua (aqua). For values in degrees, the assigned normal range is +/-0.7°; for cloudiness, +/-7%; for monthly rainfall, +/-14 mm.

 * Normal values for rainfall are based on averages for the 125 years beginning 1883.

Warm Spring 2015

 

View of Redjack Mountain from Manilla

Redjack Mountain

After cool spells in early and late September, the season was marked by two long very warm spells in early October and late November. In these, days were five degrees above normal, the air was very dry, and there was little cloud.

Weather log for spring 2015

On the average, the season was only the fourth warmest spring of the new century. Spring days had been much warmer in 2002 and in 2014, while spring nights had been just as warm in 2002, 2005, 2009, and 2014 as in 2015.
Measures of moisture (rainfall, humidity, cloud, and a narrow daily temperature range) were a little below normal, but not as low as in the last three spring seasons. Humidity (as dew point) had been extremely low in spring 2013.
The total rainfall for the season, 125 mm, was in the 31st percentile. Just four years ago, the spring rainfall total for 2011 was the record-breaking 431.7 mm.

Climate for spring 2015


 Temperature, including subsoil at 750 mm, and other data are from 3 Monash Street, Manilla.

November 2015 had warm days and nights

Photo of seeding clematis

“Old Man’s Beard”

By the last week of October, the weather had cooled down to normal. In November, this continued until the 15th, with rain falling on eight of the days. The highest rainfall reading was 30.0 mm on the 5th.
After that, the weather was fine. Both days and nights were warm, but no day got to 40°. The weekly average temperature reached about four degrees above normal, as it had done early in October.

Weather log November 2015

 Comparing November months

This was a warm November, by day and by night. However, November 2014 had been hotter, and November 2009 very much hotter. The average daily maximum temperature in November 2009 (34.3°) was nearly 3° higher than in this month (31.5°).
Moisture indicators for this month were close to normal, although there was not much cloud. The dew point is no longer very low, as in the last three Novembers.
The rainfall of 73.8 mm was above average, in the 63rd percentile. The climate graph still includes the phenomenally high rainfall of November 2011: 242.9 mm, the highest November rainfall since the record began in 1883. (The next highest was 226 mm in November 1961.)
There are now no serious shortages in rainfall totals for ANY number of months. For the last 30 years, Manilla has enjoyed rainfalls close to normal. The 30-year total of 19,449 mm to this date is within 100 mm from the median 30-year total of 19,360 mm. In all that time, the most extreme major rainfall events were the 2002 winter-spring drought, and the 2011-2012 summer deluge.

Climate for November 2015


Data. All data, including subsoil at 750 mm, are from 3 Monash Street, Manilla. Rainfall data up to 26/3/15 is from Manilla Post Office, Station 055031.

3-year trends to November 2015

Parametric plots of smoothed climate variables at Manilla
“November 2015: warm days and nights”

Trends to November 2015

November raw anomaly data (orange)

While November daily maximum anomalies were not as warm as in October, daily minimum anomalies were warmer (on the lower left graph). Apart from these, nearly all other climatic anomalies for November were near normal.

 Fully smoothed data (red)

The latest fully smoothed data (May 2015) completes the autumn months (MAM) of 2015. In that season, no variables were changing much. Daily maximum temperature, daily minimum temperature, subsoil temperature, and monthly rainfall were all near normal. Skies were rather cloudy, daily temperature range rather narrow and dew point (as is now usual) rather low. It seemed certain that the winter season would see a trend reversal: minimum values in the anomalies of daily maximum temperature and daily temperature range, and maximum values in the anomalies of daily minimum temperature, subsoil temperature, monthly rainfall, cloudiness, and dew point.

The three-year pattern

In these three years, a repeating annual cycle is best seen in the centre-right graph, which relates daily temperature range to daily maximum temperature. In May of each year the climate was relatively cool and equable (or maritime), while in October of each year it was relatively warm and extreme (or continental).


Note:

Fully smoothed data – Gaussian smoothing with half-width 6 months – are plotted in red, partly smoothed data uncoloured, and raw data for the last data point in orange. January data points are marked by squares.
Blue diamonds and the dashed blue rectangle show the extreme values in the fully smoothed data record since September 1999.

Normal values are based on averages for the decade from March 1999.* They appear on these graphs as a turquoise (turquoise) circle at the origin (0,0). A range of anomalies called “normal” is shown by a dashed rectangle in aqua (aqua). For values in degrees, the assigned normal range is +/-0.7°; for cloudiness, +/-7%; for monthly rainfall, +/-14 mm.

 * Normal values for rainfall are based on averages for the 125 years beginning 1883.

October 2015 very warm

Photo of native jasmine

Sweetest Jasmine

The first 30-degree day of the season came on the 3rd. That was ten days late, but the first 35-degree day followed soon after, on the 6th. Most days and nights were warm through the month, and the weekly mean temperature was three or four degrees above normal until the last week.
Ten sunny days were followed by days with much more cloud, and four rain days (usually seven). On the 22nd and 23rd, I recorded 17.4 and 8.0 mm.

Weather log for October

 Comparing October months

This was the warmest October of the new century for all daily temperatures: maximum, mean and minimum. The mean temperature of 21.7° was 3° above average, and much higher than in the other warm Octobers of 2014 (20.6°) and 2007 (20.4°).
The graph shows the curious fact that October months have warmed steadily since 2011. Since 2012, Octobers have not become drier: rainfall, cloudiness and humidity have increased rather than decreased.
The rainfall of 35.0 mm was below average, in the 29th percentile. As in last month’s report, there are no serious shortages in rainfall totals for small numbers of months. The only serious shortages are in the 30 month total (6th percentile) and in the 42 month total (7th percentile). There are still deep ponds in Greenhatch Creek.

Climate for October 2015


Data. All data, including subsoil at 750 mm, are from 3 Monash Street, Manilla. Rainfall data up to 26/3/15 is from Manilla Post Office, Station 055031.

3-year trends to October 2015

Parametric plots of smoothed climate variables at Manilla
“October 2015: very warm”

Trends to October 2015

October raw anomaly data (orange)

After a cool September, October was very warm: the warmest of the new century in both daily maximum and daily minimum. The daily temperature range was also high, but the soil temperature was not. Rainfall remained rather low, while cloudiness and dew point were near normal.
[The recorded anomaly values for daily maximum and for daily minimum were +3.2° and +2.2° respectively. For convenience, I have plotted them 0.2° lower.]

 Fully smoothed data (red)

In the latest fully smoothed data (April 2015) all trends on the first four graphs continued to move steadily away from drought. The daily minimum temperature anomaly began to rise, and subsoil temperature rose faster.


Note:

Fully smoothed data – Gaussian smoothing with half-width 6 months – are plotted in red, partly smoothed data uncoloured, and raw data for the last data point in orange. January data points are marked by squares.
Blue diamonds and the dashed blue rectangle show the extreme values in the fully smoothed data record since September 1999.

Normal values are based on averages for the decade from March 1999.* They appear on these graphs as a turquoise (turquoise) circle at the origin (0,0). A range of anomalies called “normal” is shown by a dashed rectangle in aqua (aqua). For values in degrees, the assigned normal range is +/-0.7°; for cloudiness, +/-7%; for monthly rainfall, +/-14 mm.

 * Normal values for rainfall are based on averages for the 125 years beginning 1883.