Tag Archives: 2011

3-year trends to October 2011

Posted in 3-year climate trends, Manilla NSW by

Parametric plots of smoothed climate variables at Manilla

“Suddenly cold and wet”

Trends to October 2011.

Raw values of some climate variables for October 2011 are like those of October 2010 which, when smoothed, turned out to be a record cold-wet climate peak. Using the two sets of graphs (above and below), one can see:

1. Raw data values (orange) and little-smoothed data values flail around wildly, but the fully-smoothed values (red) near October 2010 (at the left edge of each graph above) trace simpler, more regular curves with points more closely spaced.
2. The approach routes to the two sets of raw data October values were quite different.

Graphs from one year earlier: October 2010.

Trends to October 2010.Maximum temperature anomaly values (x-axis, all graphs)

(a) Maximum temperature partly-smoothed values in 2010 fell from normal to extremely low values taking six months;
(b) The maximum temperature smoothed value for October 2010 became the peak of a cold time: a new record low;
(c) Maximum temperature partly-smoothed values in 2011 fell from normal to extremely low values (LIKE 2010) taking only two months (UNLIKE 2010).

Rainfall anomaly values (y-axis, top left graphs)

(a) Extremely high rainfall in October 2010 followed values that had been rising steadily for eight months;
(b) The smoothed rainfall value for October 2010 became the peak of a wet time: a near-record wet;
(c) Extremely high rainfall in October 2011 (UNLIKE 2010) followed even higher rainfall in September, but normal rainfall just before that.

Cloud anomaly values (y-axis, top right graphs)

(a) Extreme cloudiness in October 2010 followed values that had been rising steadily for ten months;
(b) The smoothed cloudiness value for October 2010 was near the November 2010 peak of a cloudy time: a record for smoothed cloudiness;
(c) Extremely cloudiness in October 2011 (UNLIKE 2010) broke a 10-month trend towards LESS cloudiness.

Dew Point anomaly values (y-axis, centre left graphs)

(a) Very high Dew Points in Aug-Sep-Oct 2010 followed values that had been rising steadily for almost a year;
(b) The smoothed Dew Point value for October 2010 became the peak of a humid time: a near-record;
(c) The Dew Point in October 2011 (UNLIKE 2010) was NOT very high: it was still below normal (i.e. arid) following five months of even lower values.

Temperature Range anomaly values (y-axis, centre right graphs)

(a) Extremely low temperature range in October 2010 followed even lower values;
(b) The smoothed temperature range value for October 2010 was close to the September 2010 record peak low value (-2.80 degrees), more than twice as low as the earlier record set in June 2007 (-1.09 degrees);
(c) The temperature range in October 2011 (UNLIKE 2010) was not very low, but it was much lower than the normal values of the preceding six months.

Min temp anomaly values (y-axis, bottom left graphs)

(a) The min temp in October 2010 was normal, following a full year of very high values;
(b) The smoothed min temp for October 2010 was rather high and falling steadily;
(c) The min temps in September and October 2011 (UNLIKE 2010) were very low, following six months of normal values (UNLIKE 2010).

Subsoil temp anomaly values (y-axis, bottom right graphs)

(a) Extremely low subsoil temp in October 2010 followed a rapid fall in the preceding two months;
(b) The smoothed subsoil temp value for October 2010 was near the peak (November 2010) of a near-record time of low subsoil temp;
(c) As in October 2010, extremely low subsoil temp in October 2011 followed a rapid fall in the preceding two months (LIKE 2010).

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.

Wet cloudy October 2011 began cold

Posted in Manilla NSW, Monthly weather by

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.

 

3-year trends to September 2011

Posted in 3-year climate trends, Manilla NSW by

Parametric plots of smoothed climate variables at Manilla

“Paradoxical Trends.”Trends to September 2011.

September values are paradoxical.They show sudden reversals of trend and unusual relationships between the attributes.

Daily maximum temperature anomaly (x-axis, all graphs), which had been accelerating upwards, fell suddenly below normal.

Monthly rainfall anomaly (y-axis, top left graph), from very low in July, became extremely high.

Cloudiness (top right graph) fell suddenly to a value that was normal three years ago, but not since.

Dew Point anomaly (centre left), having been briefly near normal in August, resumed a trend to extreme aridity.

Temperature range anomaly (centre right) hovered near normal.

Daily minimum temperature anomaly (bottom left) suddenly fell even faster than that of daily maximum temperature

Subsoil temperature anomaly (bottom right), which had been above normal, fell along with daily maximum temperature anomaly.

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.

September 2011: Dry Air with Rain

Posted in Manilla NSW, Monthly weather by

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.

Winter 2011 extremely dry

Posted in Manilla NSW, Season Weather by

Weather log winter 2011For temperature, this winter was normal. Otherwise, it was strange: it had the extreme low rainfall and low humidity that come with drought, without sunny skies or severe winter frosts.
During the season, two spells of weather stood out. In mid-June cool days and very warm nights came with rain, cloud, and high humidity. The last days of July and the first week of August had very warm sunny days with very low humidity. A mid-winter spell of cold weather in mid-July was not much colder than that in early June.
The number of frosts (40) was below the average number (44). The coldest screen reading was -3.7°, exactly on the average.
The percentage of mornings with more than 4/8 cloud (50%) was a new record for winter. Winters in 2008, 2009, and 2010 had percentages in the high forties, compared with the earlier average of 34%. On four mornings fog did not clear until late; five others had some fog in the valley.
Humidity was extremely low, marked by a mean early-morning Dew Point of 1.2°, the lowest winter mean on this record.
There were 19 rain days, which is normal. However, falls were extremely light: the highest daily reading of 8.2 mm was by far the lowest maximum reading in 13 winters. The winter total of 55.0 mm is in the 11th percentile: it was the 14th driest winter on record, only slightly wetter than that in the extreme drought year 2002 (44.6 mm).Climate winter 2011

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.