August 2014 normal but with dry air

The daily weather log

Purple flowers

Early-blooming Hardenbergia

The weekly temperature was normal throughout, but the first half of the month had sunny warm days, cold nights and very dry air. The night of the 3rd (-4.0°) was the coldest August night this century, and the early morning of the 12th had the lowest August dew point (-8.7°). Two brief overcast and rainy spells began on the 16th and 26th, yielding 54.4 mm in five rain days. The reading of 26.6 mm on the 17th was one of the highest for August in recent years.
The number of frosts (12) was a little below normal (15).

Weather log August 2014

 Comparing August months

While August 2008 had been the coolest, and August 2009 the warmest in the 21st century, nearly all averages this month were near normal. As exceptions, the daily maximum temperature was slightly low and the dew point (as in the two previous August months) was very low. Few mornings had dew on the grass.
The total rainfall of 54.4 mm is in the 75th percentile, well above the August average (40 mm). This rain also raised the rainfall totals for periods of more than one month, so that only the 18-month total of 691 mm now remains as a serious shortage (9th percentile).

Climate August 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.

Dry July 2014

The daily weather log

Photo of sunlit house interior

July sun heats the house

Normal sunny July weather was broken by two rainy days in mid-month and another “rainy” day later. With the first rain there was a very warm night of 11.0°, at the time when nights are usually at their coldest (1.8°).
Late in the month days and nights were two degrees warmer than usual.Weather log July 2014

 Comparing July months

Average temperatures were normal, but the rainfall was low and the humidity (Dew Point) was very low. Recent July months have been quite different. Last July was very warm, July 2012 was very wet (ninth wettest), and July 2010 was very cloudy and wet, with warm nights. This month was not as dry as July 2011, which was not as dry as July in the drought year: 2002.
The total rainfall of 11.4 mm is in the 15th percentile. Taking rainfall totals for more than one month, the 4-month total of 83 mm is now a serious shortage (6th percentile). There are also serious shortages in the totals for 12 months (6th percentile), 15 months (8th percentile), and 18 months (9th percentile), Other totals have higher percentile values, and most totals for 36 months or more are above normal. In the very long term, the 30-year rainfall total (19,314 mm) has just fallen below the median for the first time since August 2010.
(Note. Figures for 30-year totals begin in 1914. The lowest 30-year total rainfall was 18,026 mm (601 mm per year) in November 1940; the highest was 21,031 mm (701 mm per year) in December 1978.)Climate July 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.

June 2014: normal weather

The daily weather log

Vintage machinery fair

Oil Engine’s Day Out

In four short  rainy spells, nights were very warm and days cool. Otherwise, the weather was normal but rather cloudy. There were eight rain days (normally six). The wettest had 17 mm, which is normal. Only nine mornings were frosty, when normally there are thirteen.

Weather log June 2014

Comparing June months

Most average values were near normal for June. However, the nights were warm, the daily temperature range narrow, and the skies cloudy. The month was not extremely wet and cloudy like June last year.
The total rainfall of 40.2 mm is in the 55th percentile, close to the average.. Taking rainfall totals for more than one month, only the 12-month and 15-month totals are serious shortages (7th percentile). The 3-month total (71 mm) is in the 12th percentile. Other totals have higher percentile values, and most totals for 36 months or more are above normal.

Climate June 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.

17 Years of “Droughts and Flooding Rains” at Manilla

Manilla 17-year smoothed rainfall anomaly record

Times when Dorothea Mackellar’s “droughts and flooding rains”* affected Manilla in the years from 1997 are shown by the wavy line on this graph. The climate swings in and out of times of high and low rainfall.

Peaks or troughs were often a year or two apart, but most of them were not very far from the normal rainfall value. Only two of the troughs were so far below normal that they were severe droughts: August 2002, and December 2013 (or maybe later). Milder droughts came in October 2006 and September 2009.
The rainfall in these 17 years was not below the long-term average, but slightly above it. As well as droughts there were two peaks of extremely high rainfall: in July 1998 (when the new Split-Rock reservoir suddenly filled) and in November 2011. These “deluges” had rainfall that was further from normal than the low rainfall in the droughts. Other rainfall peaks came in November 2005, October 2008, and October 2010.
In total, there were nine peaks and troughs with rainfall outside the normal range. Six of them came in the spring months of September, October or November.
Peaks and troughs in rainfall at Manilla quite often come near times of La Niña and El Niño. These are events in the record of Pacific Ocean temperatures called ENSO (El Niño – Southern Oscillation). The ENSO record for the last 17 years is shown in the second graph.

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May 2014 cloudy with warm nights

The daily weather log

Yellow berries  on a White Cedar in May.

White Cedar in May

May began cold: the 3rd was the 2nd coldest May day of this century, at 11.7°. By the 6th, the 7-day mean temperature was more than four degrees below normal. Within a week, the weather became warm and, by the 25th, the 7-day mean was more than four degrees above normal. The night of the 26th (15.3°) was the 3rd warmest May night of the century. For the first time, May had no frosts at all, and more than half the mornings were cloudy (>4/8 cloud). There were five rain days, two more than usual.

Weather log May 2014

Comparing May months

Air temperatures and the dew point were not far from normal. However, as the second graph shows, they are higher than in May months of recent years, such as 2012. Skies were extraordinarily cloudy, but the subsoil temperature was no longer high.
The total rainfall of 18.2 mm is in the 33rd percentile for May. While this is well below the long-term average of 41 mm, it is on the average for the last 15 years. Taking rainfall totals for more than one month, only the two-month total (31 mm) is a serious shortage (9th percentile). The fifteen-month total (585 mm) is in the 12th percentile. Other totals have higher percentile values, and most totals for 36 months or more are above normal. Pools still survive in Greenhatch Creek.

Climate May 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.