March 2012 a bit dry and cool

The daily weather logWeather log March 2012

Apart from a cold snap about the 9th, March was just a little cooler than usual. There were four rain days, with a maximum reading less than 7 mm. Late in the month, the weather was showery, but none of that rain fell here.

 Comparing March monthsClimate March 2012.

All the mean temperatures, and the Dew Point, were about a degree low. However, this month was not nearly as cold or as dry as March 2008, which had only 2.2 mm of rain, and barely escaped a frost.
The month was very cloudy, but not as cloudy as last year. The subsoil was very warm.
The rainfall total of 15.4 mm is well below the March average of 53.3 mm. It is in the 26th percentile: about one quarter of all March months have been drier than this one. This rather low reading hardly affects the high totals for groups of months. Totals for periods from five months to twenty-four months are still near record high values. No totals up to the thirty-year total are below normal.


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.

 

Very cool December 2011; wet year

The daily weather logWeather log December 2011.

Nearly all the days and nights of December were several degrees cooler than normal. None of them were very cold, but no days and few nights were above normal either. As in much of NSW, cool weather continued for the whole month. In a normal December, most days are warmer than 30°, but this time only four were. There were eleven rain days, often with cloud on the hills and sometimes valley fog (in summer!). The highest rainfall (2 day) reading was 22.0 mm.

 Comparing December monthsClimate December 2011.

This December was even cooler than the last. It set new post-1998 record lows for mean daily maximum temperature (27.0°), mean daily mean temperature (20.4°), and mean daily minimum temperature (13.9°). This December’s days and nights were cooler than those of November, by 2.8° and 2.1° respectively.
Mean early morning Dew Point (11.1°) was also a record low value.
The mean daily temperature range (13.2°) was a bit wider than last years record narrow value (11.7°). The sky was rather cloudy, and the mean subsoil temperature (24.0°) normal.
The rainfall of 79.0 mm is in the 58th percentile for December, above the long-term average of 74 mm. Totals for groups of months up to 24 months are now all extremely high: above the 80th percentile. The greatest rainfall “shortage” is in the 12-year total, which has the lowest percentile value (41st percentile): in the last 12 years 7621 mm of rain fell, which is just 82 mm short of the median 12-year total of 7703 mm.

The year 2011

After a very dry winter, record-breaking spring rain made this an extremely wet year. The rainfall for the year, 839 mm, is in the 86th percentile. It was not quite as wet as 1998 (919 mm; the 6th wettest) or 1996 (890 mm; the 10th wettest). These three years (1996, 1998, 2011) are the wettest in the third of a century since 1978, which had 979 mm.
In other ways, the year was nearer to normal than 2010. There were 91 rain days, fewer than last year’s record 112 rain days. It was much less cloudy, which allowed days to become warmer and nights cooler than last year, when the climate had been more equable: like that on the coast.


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.

 

November 2011 was the wettest

This was the wettest November, and the fifth-wettest month in the 129-year record.

The daily weather logWeather log November 2011.

After eight sunny dry days, half the remaining days were cloudy and wet. At first it was stormy, with over 60 mm falling in half an hour on the 13th. Persistent steady rain fell later in the month, with daily readings of 47.8, 25.0 and 62.8 mm.. The total reached 242.9 mm.
Some days in the middle of the month were rather warm, balanced later by cool days with the rain. Most nights were a little warm. Taking days and nights together, the weather was warm until the last week.

 Comparing November monthsClimate November 2011.

The record total rainfall of 242.9 mm is more than 100 mm higher than the very high November rainfalls of 2008 (132 mm), 2001 (133 mm) and 2000 (132 mm). All these are far above the November average, which is 67 mm.
Totals for groups of months up to 18 months are all very high. For longer periods, totals are not so high, but all are above the median (the 50th percentile) except for the 10-year total (43rd percentile) and the 12-year total (39th percentile).
Mean daily temperatures are above normal, especially the daily minimum, which is 2° up. However, temperatures in the heat-wave of November 2009 were much higher. This month was humid, with a morning Dew Point a degree higher than normal.


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.

 

Wet cloudy October 2011 began cold

The daily weather logWeather log October 2011.

October began very cold throughout NSW, southern Queensland and central Australia. At Manilla the maximum on Sunday the 2nd was only 13.4°: 12.6° below normal, and the coldest October day in 13 years. During the month, the air slowly warmed up to normal. The subsoil was also very cold in the second week, but only slightly cool later.
Rain fell every few days except for the week beginning on Sunday the 16th. Most rain came as showers or storms. The highest reading was 22.6 mm on the 26th. In 10 rain days (3 more than usual) the total was 97.4 mm.

 Comparing October monthsClimate October 2011.

Mean temperature readings and the Dew Point were well below normal. The average October temperature has fallen steadily since October 2007.  While that month was rather dry and sunny, October 2002 was much drier (15 mm rain) and sunnier (only 6% cloudy days).
Fifty-eight percent cloudy mornings is a record high value for October, equal with last year, and more than twice normal.
The rainfall of 97.4 mm is very high, in the 84th percentile for October (Average: 58.1 mm.). Most rainfall totals for groups of months are now high. Among groups of 108 months or less, the driest is the 30-month total which is not very dry: in the 37th percentile. In that 30 months there was 1516 mm of rain, just 100 mm below normal.


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.

 

September 2011: Dry Air with Rain

Humidity this month was extremely low. Early morning Dew Point readings averaged 1.7°, which is 3.7° below normal for September (5.4°). Relative humidity at sunrise was about 70% instead of 80%, and in the heat of the day 25% instead of 35%. This is the sixth month in a row with very low humidity, beginning with April, which had Dew Points 1.5° below normal.
In thirteen years only three months have had Dew Points further below normal. They were: July 2002 (down 3.8°), October 2002 (down 3.9°), and May 2006 (down 3.9°).
Plants are stressed by such dry air, and litter will burn easily.

The daily weather logWeather log September 2011.

Most September days were warm and sunny, but heavy rain registered on the 9th (38 mm) and on the 29th (40 mm) brought cold windy overcast weather. The 9th, at 12.9°, was the coldest September day on this record. There had been no days colder than 14°.
While many days had no cloud at all, seven days (marked “H”) had a thick smoke haze from Queensland.

 Comparing September monthsClimate September 2011.

Mean temperature readings were below normal by half a degree or more. The extremely low mean early morning Dew Point (1.7°) contrasts with the very high value last September: 7.3°
Twenty-seven percent cloudy mornings is a normal value, but lower than in the last three Septembers.
The rainfall of 91.4 mm is extremely high, in the 94th percentile for September (Average: 41.1 mm.). Rainfall totals for groups of months are all near normal. The nearest to a “drought” is the 6-month total (221 mm) which is in the 21st percentile; the nearest to a “deluge: is the 12-month total (724 mm) which is in the 68th 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.