3-year trends to July 2015

Parametric plots of smoothed climate variables at Manilla
“July 2015: cooler, moister trend”

Trends to July 2015

July raw anomaly data (orange)

The near-normal values of June are now seen as merely interrupting a trend to cooler, moister climate. July had very low day temperature, very high cloudiness, and very low daily temperature range, but dew point was not extreme. Discordantly, rainfall, which had been very high in June, became very low in July.
Night-time and subsoil temperatures continued their trends towards higher values. (Relatively warm nights have now persisted for 17 months.)

Fully smoothed data (red)

January 2015 was relatively cooler by day than the previous month, but each of the other variables moved only slightly down the graphs.

El Niño

In this record, the last hot dry climate phase that matched an El Niño was in November-December 2009. At that time, the daily maximum temperature anomaly was very high, the rainfall anomaly was low, and the daily minimum temperature anomaly (lower left graph) was a record high.
Later, in November-December 2013, without an El Niño, Manilla had a more extreme hot dry climate phase. As seen on these graphs (marked in blue), 21st century records were set then for anomalies of high daily maximum temperature, high subsoil temperature, and low dew point.
Now, in July 2015, an El Niño is forecast, but these Manilla graphs show no movement as yet away from cool moist climate.


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.

July Climate Anomalies Log

Heat Indicators log for June months

This post is the fifth in a set for the 12 calendar months. 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 July

Extreme values of July anomalies in this period were:

Subsoil Temperature anomaly +3.2 deg: July 2012;
Temperature range anomaly (minus) -3.2 deg: July 2002;
Dew Point Anomaly +3.3 deg: July 1999;
Dew Point Anomaly -3.8 deg: July 2002.

Trend lines for July

Heat Indicators

The trend of mean temperature anomalies fell below zero in 2003 then rose to +1 by 2014.
The trend of daily maximum temperature anomalies fell more slowly to -0.5 in 2007, then rose to meet the mean in 2014. The trend of minimum temperature anomaly reached an early minimum in 2002. It rose to a broad peak (+1.4) in 2010, then declined. The subsoil temperature anomaly trend was slightly low in 2004 and very high (+1.9) in 2013.Moisture Indicators log for July months

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3-year trends to July 2014

Parametric plots of smoothed climate variables at Manilla
“July 2014 dry again”

Trends to July 2014

 July data (orange)

Most raw anomaly values for July have now moved back to be like the smoothed values during the summer drought. Very few of the partially-smoothed values during the last few months suggested a trend in this direction.

Fully smoothed data (red)

January 2014 is now the latest fully-smoothed data point. Through November, December and January all variables moved decisively away from drought, except for rainfall and daily minimum temperature. In those months, rainfall remained near a (drought) minimum. Daily minimum temperature (which has a cryptic relation to drought) increased, bringing very warm nights in autumn.


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.

 

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.

Extremely warm July 2013

The daily weather logWeather log July 2013.

There were three warm spells and no cold spells in July. Fourteen days went over 20 degrees, instead of the usual four. There were only eleven frosts, the fewest in 15 July months (usually 17). In five rain days, two high rainfall figures came on the 20th (19.2mm) and the 21st (9.6mm).

Comparing July monthsClimate July 2013.

After June’s extreme cloudiness and rain, July was very near to normal in everything but temperature. The average values of daily maximum, daily minimum, and daily mean temperature were all just under two degrees above normal. The daily maximum and daily mean are 15-year record high values, but the daily minimum had been higher in July 2010: 2.4 degrees above normal.
(Note: My “normal” is the ten year average from March 1999. For the official normal period 1961-1990 there are no Manilla figures (except rainfall). This month’s very high temperatures would be (perhaps) just over 2 degrees above the 1961-1990 average.)
Rainfall, at 29.8 mm, is in the 43rd percentile, a bit below the average (41.1mm). Rainfall totals for 24 months and more are very high. This accounts for the rare appearance of water flowing locally 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.

3-year trends to July 2012

Parametric plots of smoothed climate variables at Manilla

“Back towards very wet”Trends to July 2012.

Most July 2012 anomalies are close to normal, and like those of the month before. Rainfall, however, is again very high, as in the spring and summer, and daily min temp has gone from very low in May to very high.
The subsoil remained extraordinarily warm. (Why?)

Fully-smoothed data (in red) show that the 13-year record low monthly max temp anomaly of October 2010 (-1.96 degrees) was beaten in January 2012, with a new low value of -2.03 degrees, perhaps to be beaten in the following month. At Manilla, the “flooding rains” climate phase of 2011-12 was very much wetter, and somewhat cooler than that of 2010-11.

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.

Very Wet July 2012

The daily weather logWeather log July 2012.

As in June, most weather features in July were normal, except for very warm nights with the heavy rain in the second week. Sixteen mornings were frosty, one down to minus three degrees. There were several early fogs in the valley.
Of seven rain readings, most were heavy. But the 29.6 mm value included three days.

 Comparing July monthsClimate July 2012.

Other than rainfall, there is only one variable that is not on the July average: the subsoil temperature at 750 mm is again extraordinarily warm, at 16.9°, 3.2° above normal.
The rainfall total of 91.4 mm is in the 94th percentile. Only eight July months have ever been wetter. However, July 1984, at 171 mm, was nearly twice as wet. The 12-month total to the end of July (1020 mm) is extreme. In the last 50 years, only three 12-month totals have been higher: September and October 1998 and February 1984.


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.