Summer 2014-15 on average

Wildflower photo

Commelina cyanea in Monash Street

This summer, January was no warmer than December or February, and none of these months was as warm as November! The number of hot days (over 35°) had a similar pattern that “sagged” in midsummer: Oct: 4 days; Nov: 10 days; Dec: 7 days; Jan: 2 days; Feb: 3 days; Mar: 2 days (in the first week). There were no very hot days over 40° this summer, although there had been three in spring.

A very cool spell from late January to early February had day and night temperatures 4.5° degrees lower than normal. Humidity was also low at that time and earlier, in mid-December.

Weather log for summer 2014-15

By most measures, this was a normal summer. Compared with the 21st century average, the daily maximum temperature and the daily temperature range were both just one degree low, and skies were a little more cloudy. The dew point (humidity) was low, but much higher than last summer.

The rainfall of 224 mm could hardly be more “normal”. It lies between the 125-year average of 227 mm and the 125-year median value of 221 mm. Summer rainfall totals like this also occurred in 2002-03 (227 mm) and 2008-09 (229 mm). Historically, summer rainfall totals in the “normal” range from 220 mm to 230 mm occurred in 1902-03, 1917-18, 1936-37, 1948-49, and 1957-58.

Climate for summer 2014-15.


Data. Rainfall data is from Manilla Post Office, courtesy of the Post-master, Phil Pinch. I thank Phil for his help over the years. When he retires this March, there is some uncertainty about the future of rainfall observations that have been maintained for 132 years since March 1883.

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

December 2014 rainy with warm nights

Photo of a rain-shower

A shower on Mt Baldwin

Few days or nights were unusually warm or cool, except for a very cold day on the 28th. Thunderstorm clouds were often seen, but only a few yielded any rain. Later, overcast skies brought steady rain recorded on the 27th (25.2 mm) , 28th (11.2 mm) and 29th (12.6 mm). There were fourteen rain days: twice the usual number.

Weather log December 2014

Comparing December months

The mean daily maximum temperature (31.8°) was normal, but the mean daily minimum temperature (18.0°) was very high (Very warm nights!), just below the record of 18.6° set in 2009.
Subsoil temperature (24.7°) fell to normal after two Decembers above normal.
The total rainfall of 99.0 mm was in the 72nd percentile, well above the average of 74 mm. This clears most of the shortages in rainfall totals for groups of months. Two serious shortages remain: the nine month total of 306 mm is in the 8th percentile, and the eighteen month total of 659 mm is in the 6th percentile.

Climate for December 2014

The Year 2014

This year had the warmest nights (11.34°) of the new century. Although the days, at 26.67°, were cooler than in 2002 (26.72°), this year had also the warmest mean temperature: 19.01°. The second-warmest, at 18.85°, was 2009 and the coolest, at 17.19°, was 2008.
The subsoil temperature: 20.5°, fell back to near average.
In the year, 39% of the mornings were cloudy (more than four octas of cloud). This is 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, 447 mm, was second lowest in the new century, after 2002 (366 mm). In the long-term rainfall record, this is a serious, but not severe deficiency: it is in the 8th percentile.


Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Temperatures, including subsoil at 750 mm, and other data are from 3 Monash  Street, Manilla.

3-year trends to December 2014

Parametric plots of smoothed climate variables at Manilla
“December 2014 rain again”

Trends to December 2014

December data (orange)

From November to December, the raw anomaly value for daily maximum temperature returned to normal from extremely high. Rainfall anomaly moved from very dry to rather wet. Most other anomalies came back to near zero, where they had been (as smoothed values) in June 2014, six months earlier.
Temperature range became low while daily minimum temperature remained high. (Which causes which?)

Fully smoothed data (red)

The latest fully-smoothed data (June 2014) mainly show a renewed movement towards drought.


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.

Spring 2014 dry and hotter

Weather log for spring 2014

Warm weather developed in early October, followed by a cool spell with one rain day of 26.4 mm. After that came three hot spells. There were showers and storms in the district, but little more rain fell at Manilla.
This spring was slightly hotter than spring 2013 and spring 2009, but not as hot as spring 2002. The air was not as extremely arid (dew point 3.6°) as in last spring (dew point 2.3°), and skies were a little more cloudy.
The total rainfall of 69.8 mm was in the 8th percentile: the 10th lowest spring rainfall. (Spring 2002 had been equal 5th lowest at 66 mm, and spring 1957 the lowest at 23 mm.) Rain fell on 11 days: more than in spring of 2002 (9 days), but fewer than in 2013 (13).

Climate for spring 2014


Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Temperature, including subsoil at 750 mm, and other data are from 3 Monash Street, Manilla.

3-year trends to November 2014

Parametric plots of smoothed climate variables at Manilla
“November 2014 more droughty”

Trends to November 2014

November data (orange)

The raw anomaly value for daily maximum temperature became extremely high: +5.1°. (The record positive anomaly was +5.6°, set in November 2009.) There were also extreme “droughts” values for high daily minimum temperature, high daily temperature range and low monthly rainfall. Values for cloudy days, dew point and subsoil temperature were near normal.

Fully smoothed data (red)

The latest fully-smoothed data (May 2014) complete the season of autumn 2014. The movement away from the mild drought of late 2013 ended in this month. Rainfall was rather low, skies rather cloudy, dew point low (near a new “normal”), temperature range and subsoil temperature normal.
Contrariwise, the smoothed anomaly of daily minimum temperature peaked in May 2014, showing a more maritime climatic episode.


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.

Still hot and dry in November 2014

Silky oak trees in full bloom

November Silky Oaks

Although the month began near normal, with two rain days, the weather became hot and dry again. Saturday the 22nd reached 41.4°, to be the second hottest November day on this 15-year record.
There were two heat waves, with the average weekly temperature above normal by 6.1° on the 12th and by 7.0° on Sunday the 23rd. (November of 2009 had a worse heat wave, being above normal by 9.5°, and reaching 31.3°: the hottest week in any month.)
Most nights this month were warm, with low dew points. By contrast, many days were cloudy.

 Weather log November 2014

Comparing November months

On average, the month was not quite as hot as November 2009, the hottest this century. The air was again very dry, with an early morning dew point of 7.1°, a little higher than the lowest value (5.7°) recorded for November last year.
Following only three years after the wettest November on the 130-year record (242.9 mm), the total rainfall of only 24 mm was in the 15th percentile. That is, such low November rainfalls happen about one year in seven. However, the time since a lower November rainfall (15 mm in November 1990) is thirteen years: the longest gap ever.
For the third month in a row, little changed in rainfall totals for periods of more than one month. There is no longer a serious shortage in the 6-month total (now in the 10th percentile) but there are now serious shortages in the totals for 5 months (9th percentile), 9 months (8th percentile), 15 months (6th percentile), 18 months (6th percentile), and 30 months (9th percentile). There is one severe shortage: the total for 12 months (393 mm) is in the 4th percentile.

Climate fro November 2014


Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Temperatures, including subsoil at 750 mm, and other data are from 3 Monash  Street, Manilla.

October 2014 hot and dry

Blooms of Melia azedarach

Fragrant white cedar blooms

The month began with a warm spell, which was followed by a cool spell about the 15th. It ended with a long hot spell, 4.8 degrees above normal, including the hottest October day this century (38.1°) on the 26th. As usual, there were no frosts.

Of three rain days (usually seven), only the 14th had much rain: 26.4 mm, with heavy showers.
Half the mornings had no cloud at all, and nine days had very wide temperature ranges, greater than 20°.

Weather log October 2014

 Comparing October months

This was the hottest October month at Manilla in this 16-year record. Maximum, mean and minimum temperatures were all highest values, but the maximum was no higher than in October 2007. The subsoil temperature returned to a value below normal.
As indicators of low moisture, the daily temperature range was very high and cloudiness and dew point were very low, as in the last two October months. Even less cloud had been seen in 2002 and 2004.
Recently, lower rainfall occurred in October 2002 (15.0 mm), 2012 (12.6 mm), and 2013 (15.0 mm). However, this month’s total of 27.0 mm is well below the October average of 58 mm, in the 21st percentile. Since last month, little has changed in rainfall totals for periods of more than one month. There is still a serious shortage in the 6-month total (8th percentile) but not now in the 9-month total (10th percentile). The 15-month total has advanced to severe (4th percentile), while the 18-month total has retreated to serious (5th percentile). A serious shortage has also appeared in the 30-month total (8th percentile).

Climate October 2014  


Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Temperatures, including subsoil at 750 mm, and other data are from 3 Monash  Street, Manilla.