3-year trends to December 2018

December hot and dry

3-year trends to December 2018

December raw anomaly data (orange)

In December 2018, the top two graphs show that rainfall was low and skies sunny.
The daily maximum temperature (x-axes, all graphs) and daily minimum temperature (lower left graph) were extremely high, but the subsoil was cool. Dew point and daily temperature range were near normal.

 Fully smoothed data (red)

Climate anomaly data when smoothed in this way do not show changes from month to month, but only those cycles that last for a year or more. The smoothed data identify the month when a peak occurs in a cycle .

By June 2018, the last date for which data can be fully smoothed (as described below), some variables had already peaked in their contribution to the current extreme drought.

The anomaly of daily maximum temperature (x-axis, all graphs) had peaked in March 2018. Two months later, in May 2018, the rainfall anomaly peaked (negative) to a 21st-century record low value of minus 28.3 mm. (In the 2002 drought daily maximum temperature had not peaked until after the peak of minimum rainfall.)
By June, cloudiness was decreasing towards a minimum (perhaps in August 2018) without becoming much less cloudy than normal. Dew point anomaly was still decreasing, and seemed likely to reach a record low value about August.
The anomaly of daily temperature range had been at a (high) level characteristic of drought since the previous winter (2017). It had changed little, and peaked in May 2018 without getting near the record high value of July 2002.
The anomaly of daily minimum temperature has a cryptic relation to drought. In this case, the value peaked sharply in February 2018 before falling rapidly. It may have reached a minimum about August 2018.
The anomaly of subsoil temperature was high in June 2018, and seemed likely to peak about July, lagging four months behind the daily maximum temperature anomaly.


Notes:

January data points are marked by squares.

Smoothing

Smoothing uses Gaussian functions.
For fully smoothed data the function has a Standard Deviation of 2.5 months, it spans 13 monthly data points, and has a half-width of 6 months, which suppresses cycles shorter than 12 months. For partly smoothed data, the span of the function is reduced to 11 months, 9 months and so on.

Fully smoothed data points are plotted in red, partly smoothed data uncoloured, and raw data for the last data point in orange.

Limiting values

Blue diamonds and the dashed blue rectangle show the extreme values in the fully smoothed data record since September 1999.

Normal values

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.

November 2018 began hot

A King Parrot feeding in a Hopbush

King Parrot in Hop Bush

The month began hot, with the weekly temperature more than six degrees above normal. On the 6th, the maximum reached 39.4° after a warm overnight low of 22.1°. However, rain brought a maximum of only 21.5° on the 8th. In the rest of the month temperatures were near normal. Just one morning (the 24th) had an exceptionally low dew point that was 14° below normal.
There were eight rain days, with the highest reading 17.2 mm, on the 22nd.

Weather log November 2018

Comparing November months

Although the month began so hot, the average temperature (22.7°) was only 1° above normal, and not nearly as high as in November 2014 (25.4°) or November 2009 (26.0°).
Despite the continuing drought, the only indicator showing low moisture was the early morning dew point (7.3°). There was quite a lot of cloud (43%) and a rather narrow daily temperature range (14.4°).
The rainfall total of 50.2 mm (estimated) is at the 36th percentile for November, somewhat below the average (67 mm).
I have reported the drought in another post.

Climate in November 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 record was again defective in November 2018. No 9 am readings were recorded. 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.

3-year trends to November 2018

Not So Moist

3-year trends to November 2018

November raw anomaly data (orange)

In November 2018, the top four graphs show that raw values of moisture anomalies moved up away from the moist values of October, but not as far as earlier drought values.
For temperature anomalies, daily maximum and subsoil rose again, while, daily minimum fell from its extremely high value

 Fully smoothed data (red)

At this time, Manilla was entering an extreme drought. Each of the smoothed climate anomalies shown on these graphs contributed to the drought to some degree, and with more or less lag.

By May 2018, the last date for which data can be fully smoothed (as described below), most variables had not yet peaked in their contribution. Several more months of data will reveal the complete cycle into and out of drought.
The anomaly of daily maximum temperature (x-axis, all graphs) had already peaked in March 2018. (In the 2002 drought daily maximum temperature had peaked after the peak of minimum rainfall, not before.)
In May 2018 the rainfall anomaly was still becoming more negative, to a record low value of minus 28.3 mm . June and July rainfall anomalies seemed likely to be similar after smoothing.
Cloudiness was decreasing towards a minimum (perhaps in August 2018) without becoming much less cloudy than normal.
Dew point anomaly was still decreasing, and seemed likely to reach a record low value about August.
The anomaly of daily temperature range had been at a (high) level characteristic of drought since the winter of 2017. It had changed little since, and seemed likely to peak in June 2018 without approaching the record value of July 2002.
The anomaly of daily minimum temperature has a cryptic relation to drought. In this case, the value peaked sharply in February 2018 before falling rapidly. It may have reached a minimum about August 2018.
The anomaly of subsoil temperature was rising rapidly in May 2018, and seemed likely to peak about July, lagging four months behind the daily maximum temperature anomaly.


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.

Moist October 2018

Green grass in a drought

Greenness that thickens

No temperatures were extreme, but many nights were warm. The weekly temperatures were three or four degrees high after the middle of the month. The sunniest days had low early morning dew points.
There were eight rain days, with the highest reading 15 mm, on the 11th.

Weather log, October 2018

Comparing October months

While the mean temperature (20.3°) was just above normal, this month was as moist as October 2017. Despite the continuing drought, the daily temperature range was low (14.9°), the cloudiness high (52%), and the dew point high (7.2°).
The rainfall total of 51.6 mm (estimated) is at the 45th percentile for October, not far below average (58 mm).
I have reported the drought in another post (“Contours of Manilla’s 2018 Drought”).

Climate in October 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 record was again defective in October 2018. No 9am readings were recorded. 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.

3-year trends to October 2018

Moist

3-year trends to October 2018

October raw anomaly data (orange)

In October 2018, raw values of three anomalies moved low on the graphs, showing more moisture . They were: cloudy days percent, dew point, and (narrow) daily temperature range. Rainfall increased from very low back to normal.
For temperatures, daily maximum fell to normal, daily minimum rose extremely high, and subsoil temperature fell very low.

 Fully smoothed data (red)

Fully smoothed data for April 2018 did not break the previous month’s record for daily maximum temperature anomaly (x-axis), as I had thought it would.
The April smoothed rainfall anomaly of minus 27.8 mm (top left graph) beat the 21st-century record minus value of 27.1 mm set in July 2002.
In April 2018, the trend for decreasing rainfall with increasing daily maximum temperature (top left graph), which had had lasted eight months, altered as temperature began to fall.. At that date, the three other moisture anomaly variables were moving rapidly up the graphs towards drought.
Daily minimum temperature anomaly was falling from a recent maximum in February. Subsoil temperature anomaly continued its sustained rapid rise.


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.