Monthly Archives: June 2010

3-year trends to May 2010

Posted in 3-year climate trends, Manilla NSW by

Parametric plots of smoothed climate variables at Manilla
“Temperatures normal”

Trends to May 2010

Manilla’s climate in the last three years has been marked mainly by cloudier skies and a narrower daily temperature range.

Raw anomaly values for climate variables for May 2010 (orange) were normal for daily maximum, daily minimum, and subsoil temperatures and for daily temperature range. Rainfall and humidity (dew point) were rather low, but skies were very cloudy.
Fully-smoothed data (red) for November 2009 showed a record value for daily maximum temperature anomaly, which seemed likely to be a peak value.

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.

(Note added in May 2014:

This post titled “3-year trends to May 2010” is the first of a consecutive series of parametric plots, updated monthly at the time of observation and originally posted elsewhere.
Data exists back to March 1999, but the earlier data was not edited in this form at the time.
To display all existing fully-smoothed data points at least once, I have prepared back-dated posts in this same format for:
“3-year trends to August 2002” which includes smoothed data September 1999 to February 2002, covering the calendar years 2000 and 2001.
“3-year trends to August 2004” which includes smoothed data September 2001 to February 2004, covering the calendar years 2002 and 2003.
“3-year trends to August 2006” which includes smoothed data September 2003 to February 2006, covering the calendar years 2004 and 2005.
“3-year trends to August 2008” which includes smoothed data September 2005 to February 2008, covering the calendar years 2006 and 2007.)

Damp end to cloudy May 2010

Posted in Manilla NSW, Monthly weather by

The daily weather logWeather log May 2010

Dry weather with warm days and cool nights lasted most of the month. On the 13th the early morning Dew Point of -6.3° set a record for low humidity in May. The seven-day average temperature was quite low in the second week. Nine mild frosts (usually 6) all came about this time. By the 25th there had been only 57 mm of rain in 14 weeks: an average of barely 4 mm per week. A serious rainfall shortage was developing, despite months of cloudy weather.
Late in the month nights became very humid and warm. Mornings had fog on the 18th and 22nd and mist (visibility one kilometre) on the 27th and 31st. Three days had more than 5 mm of rain. In all, the month had 8 rain days, totalling 28.0 mm.

 Comparing May monthsClimate May 2010

This was the cloudiest May in the 11-year record. The mean maximum temperature and the mean average were normal. The mean minimum was up, reducing the daily temperature range, and the mean Dew Point was down.
The rainfall of 28.0 mm is near the median for May (51st percentile). It is below the long-term average of 40 mm, but no May total has beaten the average since 1998! Rainfall totals for groups of months show just one serious shortage. The 15-month total (538 mm) is now down to the 7th percentile.

Subsoil Temperature

Both graphs now include subsoil temperature measured at 750 mm depth. There the temperature barely changes during a day. It changes slowly with the seasons. Usually it ranges from 26° in February to 14° in July.
As observed in Manilla, the  subsoil temperature does not relate to the normal average temperature of the air in a simple way. In May, it stays about five degrees warmer; in other autumn and winter months it is less than five degrees warmer. In spring and summer it is almost the same as the normal average air temperature.
In autumn 2007 the subsoil temperature was nearly two degrees warmer than usual; in autumn 2008 it was one degree cooler than usual. This is a puzzle, because the average air temperature did not change so much.

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.