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.

3-year trends to October 2017

Avoiding drought

3-year trends to October 2017

October raw anomaly data (orange)

October 2017 was moist: all moisture indicators had dropped sharply down the graphs, retreating from the aridity of August and September. Daily maximum temperature anomaly (x-axis in all graphs) fell towards normal, while that of the subsoil (lower right graph) remained low. Daily minimum temperature anomaly (lower left graph) jumped from extremely low to extremely high.

 Fully smoothed data (red)

The latest fully-smoothed data point is that for April 2017.
At that time, the climate was warm and almost static. There was a pause in a drift towards aridity.


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.

October 2016 was cold

Photo of the bark of a Eucalyptus tree

White Box at Sunset

In this month, each of five sunny spells of normal temperature was followed by a cold, cloudy, humid break, generally with rain. Only a few days were warmer than normal, including the 27th. That was the first 30° day of the season, five weeks late.
The average weekly temperature was persistently three or four degrees cooler than normal. One cold week about the 15th was more than five degrees below normal, and the warmest week, about the 29th, was still half a degree low.
Most nights were very cool. I recorded no frosts, but others may have done. My most recent frost was early in September.
There were six rain days, not counting two readings of 0.2 mm. The highest reading was 20.0 mm on the 23rd.

Weather log for October 2016

Comparing October months

This was the coldest October on this record from 1999. That includes not only the maximum, mean, and minimum air temperatures read in the Gill Screen, but also the subsoil temperature at 750 mm. Noting that October 2015 had the highest October temperatures, the sudden collapse is astonishing. Last October was three degrees warmer than normal; this month was almost three degrees colder than normal. Put another way, the seasonal warming is a month late this year and was a month early last year.
Unlike September, there was not an unusual amount of moisture in October. Humidity, cloudiness and daily temperature range were near normal.
The monthly rainfall total of 72.1 mm was above the average of 58 mm, in the 70th percentile.
I have discussed the current drought status (that is, drought-free) in another post.

Climate for October 2016


Data. Rainfall figures are usually from the automatic rain gauge at Manilla, published on the internet by the Bureau of Meteorology as Station 55031. However, the gauge ceased recording on the 8th of October, and later readings are from my non-standard gauge. All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

3-year trends to October 2016

Parametric plots of smoothed climate variables at Manilla
“October 2016 still cold”

Trends to October 2016

October raw anomaly data (orange)

In October 2016 daily maximum air temperature continued extremely low. Now daily minimum air temperature and subsoil temperature (bottom graphs) also became extremely low. Most other variables returned to near normal.

 Fully smoothed data (red)

The latest fully-smoothed data point is April 2016.
By then, most anomalies were moving definitely towards cool and moist. However, daily minimum temperature and subsoil temperature were rising.
In April 2016, the smoothed anomaly of daily minimum temperature was extremely high. It was approaching the 18-year record value of +1.32°, set in December 2009.


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.

October 2015 very warm

Photo of native jasmine

Sweetest Jasmine

The first 30-degree day of the season came on the 3rd. That was ten days late, but the first 35-degree day followed soon after, on the 6th. Most days and nights were warm through the month, and the weekly mean temperature was three or four degrees above normal until the last week.
Ten sunny days were followed by days with much more cloud, and four rain days (usually seven). On the 22nd and 23rd, I recorded 17.4 and 8.0 mm.

Weather log for October

 Comparing October months

This was the warmest October of the new century for all daily temperatures: maximum, mean and minimum. The mean temperature of 21.7° was 3° above average, and much higher than in the other warm Octobers of 2014 (20.6°) and 2007 (20.4°).
The graph shows the curious fact that October months have warmed steadily since 2011. Since 2012, Octobers have not become drier: rainfall, cloudiness and humidity have increased rather than decreased.
The rainfall of 35.0 mm was below average, in the 29th percentile. As in last month’s report, there are no serious shortages in rainfall totals for small numbers of months. The only serious shortages are in the 30 month total (6th percentile) and in the 42 month total (7th percentile). There are still deep ponds in Greenhatch Creek.

Climate for October 2015


Data. All data, including subsoil at 750 mm, are from 3 Monash Street, Manilla. Rainfall data up to 26/3/15 is from Manilla Post Office, Station 055031.

3-year trends to October 2015

Parametric plots of smoothed climate variables at Manilla
“October 2015: very warm”

Trends to October 2015

October raw anomaly data (orange)

After a cool September, October was very warm: the warmest of the new century in both daily maximum and daily minimum. The daily temperature range was also high, but the soil temperature was not. Rainfall remained rather low, while cloudiness and dew point were near normal.
[The recorded anomaly values for daily maximum and for daily minimum were +3.2° and +2.2° respectively. For convenience, I have plotted them 0.2° lower.]

 Fully smoothed data (red)

In the latest fully smoothed data (April 2015) all trends on the first four graphs continued to move steadily away from drought. The daily minimum temperature anomaly began to rise, and subsoil temperature rose faster.


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.