3-year trends to June 2020

June: again warm and dry

3-year climate trends at Manilla

June raw anomaly data (orange)

Temperatures

Daily maximum temperature anomaly (all x-axes), having been negative for three months, returned to positive.
Daily minimum temperature anomaly (lower left): returned from normal to positive.
Subsoil temperature anomaly (lower right): returned from normal to positive.

Moistures (moist is at the bottom)

Rainfall anomaly (upper left) returned from normal to negative (dry).
Cloudiness anomaly (upper right): returned from high (cloudy) to near normal.
Dew point anomaly (middle left): remained normal.
Daily temperature range anomaly (middle right) returned from narrow to near normal.

 Fully smoothed data values (red) 

Fully-smoothed data for December 2019 shows that only the daily minimum temperature was increasing. Other temperatures became cooler, and all the moisture indicators (rainfall, cloud, dew point, and daily temperature range) moved downward, showing decreasing drought.

[Note.
Due to illness, 45 days were missed for some Manilla values, mainly in April 2020. No values were noted for cloud or soil temperature; daily maximum and minimum air temperatures were estimated by regression on values from Tamworth Airport Automatic Weather Service.]


Notes:

January data points are marked by squares.

Smoothing Continue reading

Warm, Dry February 2019

Photo of bushfire smoke at 40 km.

Bushfire at Warrabah

The month began warm, with weekly temperature three degrees above normal, but it ended slightly cool. Day and night temperatures remained near normal. The highest maximum was just under 40°.
The morning of the 13th had very dry air, with a dew point of only 1.7°. (Serious bushfires were burning that day.)
There were only 2 rain days (usually 7). Neither recorded as much as 7 mm.

Graphical log for Feb 2019

Comparing February months

After the extreme heat of January, February was only 1° warmer than normal, by day and by night.
Two indicators of moisture, cloudiness and daily temperature range, were normal. However, the mean early morning dew point, 9.2°, showed the lowest February humidity this century.
The monthly rainfall of 10.6 mm was at the 9th percentile, far below the average (67 mm). This was the 12th driest February, but it had more rain than either February 2017 (6th driest) or February 2015 (ninth driest).
I have reported the on-going drought in another post.

The last 7 February months


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.  Since no 9 am readings have been recorded since August, I have substituted my non-standard gauge readings for all days.
All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

Winter 2018 had the driest air

A gum-tree blowing in the wind

Wind-blown Gum-tree

Temperatures varied widely, especially at night. In both mid-July and mid-August, the weekly mean night temperatures were more than 4° low. At these times, the air was extremely dry.
Early in July night temperatures were nearly 4° high, while late in July it was the day temperatures that were more than 4° high. The daily temperature range was almost 21° in mid-July, having been less than 13° in mid-June.
There were 16 rain days, but the highest reading (estimated) was only 10.2 mm.

Weather log for winter 2018

Last winter’s report had been headlined: “Dry air in winter 2017”. This winter was even drier by all measures. In particular, the mean early morning dew point set a new record of -3.0°. The best match in this century is the winter of 2002. Both had warm days, cold nights, wide daily temperature range, little cloud and low dew point.
The total rainfall of 42 mm makes this the 9th driest winter on record, displacing winter 2002, which had 44 mm. (The year 1888 had the lowest winter rainfall total: 6 mm. However, daily readings are missing. The next lowest was 1946, with 29 mm, then 1972 and 1982, both with 32 mm.)

Climate for winter 2018


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. During this winter season 20 daily readings were missed, including several days with significant falls of rain. I have used my own readings for the whole season.

All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

Autumn 2018 dry and very warm

Gum nuts and blossoms

Gumnut and Gum-Blossum

The air became four degrees warmer than normal by day and by night in mid-March and continued warm until late in April. As normal temperatures returned the climate became dry, with no rain for thirty-nine days.

Graphical weather log for autumn 2018

Both autumn 2016 and autumn 2018 had record high average temperatures. This season had the highest mean daily maximum (27.7°), but 2016 had the highest mean daily minimum (12.1°). In the combined average, 2016, with 19.9°, was warmer than 2018, with 19.7°.

All four indicators of moisture (rainfall, dew point, cloud, and daily temperature range) agree in showing this autumn to be drier than last autumn, and even than the three autumns before that.
The total rainfall of 45 mm was the 12th driest on record, but it was not the driest in the 21st century. Similarly dry autumns occurred in 2002 (60 mm), 2005 (35 mm), 2006 (53 mm), and 2008 (37 mm). That is about twice as many as history would suggest.

Climate for autumn 2018


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. During this autumn season 30 daily readings were missed, and I replaced them with my own readings.

All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

March 2018 very warm indeed

Acacia salicina

Young Cooba

Eight days went over 35° this March, beaten only by nine days in March 2016. The 19th (38.6°) was the fifth hottest March day of the new century. Weekly mean temperatures rose to 4.6° above normal by the 18th, and remained almost as high beyond the end of the month.
There were seven rain days, with the highest reading of 16.5 mm (est.) coming early in the month.

Weather log for March 2018

Comparing March months

Average temperatures this month very nearly match those of the record-breaking March 2016. They are only 0.1° lower! Moisture variables are also similar: rather dry, in stark contrast to the sogginess of March 2017.

The rainfall total of 25.6 mm (est.) was at the 40th percentile, well below the average (53 mm). Serious rainfall shortages are seen only in the medium term: the 60-month total of 2770 mm (8th percentile) and the 72-month total of 3410 mm (9th percentile).

Climate in March months


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.  The gauge, which had last reported on 24 September 2017, came on line again on the 16th of March. However, not all later days have readings reported.

All data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.