3-year trends to February 2015

Parametric plots of smoothed climate variables at Manilla
“February 2015: very dry”

Trends toFebruary 2015

  February raw anomaly data (orange)

In February, most anomalies moved back towards “droughts” from the “flooding rains” values of January. Rainfall became extremely low, but daily maximum temperature did not rise as far as “normal”.
Exceptionally, February daily minimum temperature and subsoil temperature became very low.

Fully smoothed data (red)

The latest fully-smoothed data anomalies (August 2014) complete the winter of 2014. Through the winter season, most values were static and near normal. (Dew point, like most recent values of that variable, was 3 degrees lower than normal.)


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.

February 2015 a very dry month

Photo of a baby Kookaburra

Baby Laughing Kookaburra

After a very cool first week, normal temperatures returned, both by day (33°) and by night (18°) . Early on, most mornings were sunny. Later, many were almost overcast, but only three days had light rain, with a maximum of 3.4 mm.

Weather log  February 2015

Comparing February months

Most of the last seven February months have been unusual in some way. This month was very dry, with near-record low rainfall and very low humidity. By contrast, February 2012 was very wet, as well as very cool. Both 2011 and 2014 were very warm, but 2011 was also very cloudy and humid. February 2013 was the coolest, without being wet like 2012.
The total rainfall of 7.6 mm this month was very low (6th percentile): this was the 8th driest February, and the driest since 1989, which (like 1974) had 7.0 mm. Still, taking rainfall totals for groups of months, only the 24-month total (985 mm) is a serious shortage, in the 9th percentile.

Climate forFebruary 2015


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.

With the retirement of the Post-master, Phil Pinch, the future of rainfall observations at Manilla Post Office (055031), kept for 132 years since March 1883, is uncertain.

February Climate Anomalies Log

Heat indicators log for February

This post is the twelfth in a set for the 12 calendar months that began with March. Graphs are sixteen-year logs of the monthly mean anomaly values of nine climate variables for Manilla, NSW, with fitted trend lines. I have explained the method in notes at the foot of the page.

Raw anomaly values for February

Extreme values of February anomalies were as follows:

Daily Maximum Temperature Anomalies (3) -4.2 deg: February 2008; -3.3 deg: February 2012; -3.3 deg: February 2013;
Daily Mean Temperature Anomalies (1) -3.3 deg: February 2008;
Rainfall Anomalies (1) +120 mm: February 2012;
Dew Point Anomalies (2) -4.6 deg: February 2014; -4.6 deg: February 2015.

Trend lines for February

Heat Indicators

All heat indicator quartic trends began slightly low and ended slightly low. They had a low peak about 2004, and a trough later. The trough was deepest and earliest for daily maximum temperature (2011), followed by daily mean temperature in 2012, daily minimum temperature in 2014, and subsoil temperature in 2015 or later.

Moisture indicators log for February

Continue reading

3-year trends to February 2014

Parametric plots of smoothed climate variables at Manilla

“Drought advanced in winter; now retreating”Trends to February 2014

Raw values of climate anomalies for February 2014 moved positively away from the high temperature and low moisture of “droughts”. Daily minimum temperature increased but this, too, goes with more moisture.
Data points for the three months of winter 2013 are now fully-smoothed. They show a steady progress towards drought in increasing maximum temperature and daily temperature range, and reducing rainfall, cloudiness, and humidity (dew point). Daily minimum temperature and subsoil temperature  peaked already in July.

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.

Warm Dry February 2014

The daily weather logWeather log February 2014.

The month began sunny and dry, with extremely low humidity. The second week brought a warm spell, which became humid and cloudy, leading to rain. There were eight rain days, with 18.8 mm recorded on the 17th. The fourth week was fine, with normal temperatures.

Comparing February monthsClimate February 2014.

Like February 2011, this month was very warm, but not quite as warm as February 2006. February 2008 had been five degrees cooler, and February 2012 and 2013 also very cool.
The humidity, shown by early morning dew point, has fallen steadily for four February months. It was 15.6° in 2010, and is now a record low of 10.3°. February mean relative humidity values, which had been steady from 2006 to 2013, fell sharply to 2014: afternoon values fell from 31% to 16% and morning values from 80% to 58%.
The total rainfall of 37.4 mm is well below the February average of 67 mm and far below that for February 2012 (194 mm), the fifth wettest on record. This is the forty-fourth driest, and in the 35th percentile. Taking rainfall totals for more than one month, the greatest shortages are not serious (i.e. not below the 10th percentile). The two month total (39 mm) and the twelve-month total (452 mm) are both in the 12th percentile. Other totals have higher percentile values, and most totals for 30 months or more are above normal. Pools survive in Greenhatch Creek.


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.