January 2020 more humid

Rain in the main street

It rained!

Weekly average temperatures were 7 deg high early in the month, normal in the third week, then 6 deg high at the end. In these hot weeks, ten days went over 40 deg.
The night of the 11th, at 28.1 deg, was extremely warm. It was the 2nd warmest on record, after 28.2 on 14/01/17.
Although the wettest day had only 22.8 mm of rain, there were 11 rain days. Other signs of moisture included 11 days with half cloud cover or more, and 9 mornings with dew points over 20 deg.

Weather log January 2020

Comparing January months

Mean temperatures this month are the 2nd highest for January, being lower than last year. Subsoil temperature is normal.
All moisture indicators are higher. The early morning dew point, at 16.8 deg, is remarkably high, exceeded only in January 2006.
The rainfall total of 46.8 mm is at the 28th percentile for January, well below the average of 87 mm.

January climae

Drought

I will report separately on the on-going drought that continues to break low-rainfall records at durations of 15-months and longer.


Data. A Bureau of Meteorology automatic rain gauge operates in the museum yard. From 17 March 2017, 9 am daily readings are published as Manilla Museum, Station 55312.  These reports use that rainfall data when it is available. Recording resumed on 20 July 2019.
My estimates of early morning dew point have drifted anomalously low. From August 2019, I use data from the Tamworth Airport published graphs.
All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

3-year trends to January 2020

January much more humid

3-year climate trends to Jan 2020

January raw anomaly data (orange)

Temperatures

Daily maximum temperature anomaly (all x-axes) high, but not now extreme: now only three degrees above 21st century normal.
Daily minimum temperature anomaly (lower left): extremely high, twice as high as the record smoothed value
Subsoil temperature anomaly (lower right): still near normal.

Moistures (moist is at the bottom)

Rainfall anomaly (upper left): no longer extremely low.
Cloudiness anomaly (upper right): back to normal.
Dew point anomaly (middle left): suddenly rather high (humid).
Daily temperature range anomaly (middle right): suddenly narrow, due to cloud.

 Fully smoothed data values (red) 

Smoothed anomaly values now include July of 2019. From the rather static values of the autumn, nearly all smoothed values for June began to move in the direction towards drought that seems to have persisted through spring.
There were two exceptions. Daily minimum temperature anomaly continued to fall. Subsoil temperature anomaly reached a peak value in June.


Notes:

January data points are marked by squares.

Smoothing Continue reading

December 2019: very hot and dry

Sun in smoke

Red Sun 17 Dec

After the first week, each week in December was very hot, reading up to 5.9° above normal. Both days and nights were hot, but only one record was set: 42.2° on the 21st was the hottest December day. That was well below the record hot day of 44.9° set on 11/2/17.
Twenty mornings were cloudless which was twice the usual number. Smoke from mainly coastal bushfires reduced visibility to 15 km or less from the 8th to the 25th. Early in the month, rain fell on three days, the highest reading being 12.4 mm on the first day.

December 2019 weather

Comparing December months

This month broke 21st century records for December mean monthly temperatures. The mean minimum of 18.7° just beat 18.6° of December 2009, the mean average of 27.6° easily beat 26.1° last year, while the mean maximum of 36.5° was far above last year’s 33.9°.
On balance, indicators of moisture make this the driest December of the century. Rainfall, at 19.6 mm, was lower than any but December 2006 (18.8 mm), and the dew point was equal lowest with 2013. This month had by far the fewest cloudy mornings (10%) and the widest daily temperature range (17.8°).

December 2019 climate

Drought

I will report separately on the on-going drought that continues to break low-rainfall records at durations of 15-months and longer.


Data. A Bureau of Meteorology automatic rain gauge operates in the museum yard. From 17 March 2017, 9 am daily readings are published as Manilla Museum, Station 55312.  These reports use that rainfall data when it is available. Recording resumed on 20 July 2019.
My estimates of early morning dew point have drifted anomalously low. From August 2019, I use data from the Tamworth Airport published graphs.
All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

3-year trends to December 2019

December dry and very hot

3-year trends of climate anomalies

December raw anomaly data (orange)

Temperatures

Daily maximum temperature anomaly (all x-axes) extremely high: now five degrees above 21st century normal and three degrees above the record for smoothed values.
Daily minimum temperature anomaly (lower left): very high, just above the record smoothed value.
Subsoil temperature anomaly (lower right): still near normal.

Moistures (moist is at the bottom)

Rainfall anomaly (upper left): extremely low.
Cloudiness anomaly (upper right): extremely low.
Dew point anomaly (middle left): still rather low.
Daily temperature range anomaly (middle right): very high.

 Fully smoothed data values (red) 

Smoothed anomaly values now include June of 2019. From the rather static values of the spring, nearly all smoothed values for June began to move in the direction towards drought that seems to have prevailed since then.
There were two exceptions. Daily minimum temperature anomaly continued to fall very rapidly. Subsoil temperature anomaly approached a peak value.

Detail of rainfall vs. max temp

Rainfall and temperature anomaly trendsThe relation of smoothed rainfall anomaly to smoothed daily maximum temperature anomaly (top left graph) is important, but the graph is hard to read. I have drawn a part at a larger scale here.
The value for September 2017 is the first to show the current drought by falling on the hot-dry side of the normal range (aqua). Values became successively warmer and drier until March 2018 (max temp) and May 2018 (min rain). Values (especially temperature) then cycled away from drought until August-September 2018, and back to record-breaking drought in January 2019.
After January 2019, there was a retreat from drought until May 2019, when anomaly values were like those of 17 months earlier, in January 2018 (red square).
June 2019 began a renewed cycle towards drought, seemingly confirmed by later data.


Notes:

January data points are marked by squares.

Smoothing Continue reading

“Novel graphs for rainfall shortages”

I display my drought poster

Garry’s drought poster

Drought poster for conference

Grasslands Conference Poster Display

A conference paper about drought graphs

This blog “Climate by Surly” has analyses of the current drought at Manilla, mainly in the form of graphs. I was invited to present these findings as a “Poster Paper” at a conference of the Grassland Society of NSW at Gunnedah in July 2019. The poster itself is shown in the photo and the reduced image above.

The paper

The paper is published in two parts: the colour poster shown above, and four pages of text and figures. Both have the title “Novel graphs show extreme rainfall shortages”.
The point of my paper was that these novel graphs bring out features of the current drought at Manilla in a way that could be applied at other times and places.
Because the paper is brief, I have referred the reader to further information in posts in this blog. The construction of each of the three kinds of graph is fully explained in the posts that I linked:
/2019/03/31/march-rain-leaves-drought-extreme/
/2019/04/09/rainfall-shortage-sequence-03-2019/
/2019/04/15/rainfall-shortage-history-manilla/
/2019/04/16/rainfall-shortage-jan-2000-mar-2019/

The complete reference to the paper is:
Speight JG (2019) Novel graphs show extreme rainfall shortages. In
‘Proceedings of the 31st Conference of the Grassland Society of NSW Inc.’ (Eds SR Murphy, SP Boschma, and M Simpson). pp. 36-39. (Grassland Society of NSW Inc., Orange).

The text can be accessed here as a pdf:

Click to access 6-2019-grassland-conf-proc-speight-pp35-39-web-ver.pdf

The paper will become accessible on the website of the Grassland Society of NSW.

The Poster on display

Thanks to the generosity and interest of the proprieters, the original of the poster can be seen at Molly May’s Coffee Shop in the main street of Manilla.