Ranked Hot and Cold Days

Graphs like this show how the trends of temperature differ between the coldest days (or nights) of the year, the hottest ones, and all those ranked in between.

This first post on this topic is a “sampler” of Manilla data that I will present. It compares my first 9-year period March 1999 to February 2008 with the 9-year period September 2003 to August 2012, four and a half years later.

Graphs showing trends of temperatures for ranked days.

All the days (or nights) of the year are arranged from the coldest on the left to the hottest on the right. Columns show by how much the day or night of that rank has trended warmer or cooler during the nine years. (See also Notes below.)

1. Days
In the earlier period (blue), most winter days and a few mid-summer days cooled at 0.1 to 0.2 degrees per year. Days in spring and autumn, and cooler days in summer warmed at less than 0.1 degrees per year.
In the later period (red), all days of the year cooled, but there was a gradient from no cooling in midwinter to extremely rapid cooling (more than 0.3 degrees per year) in midsummer.

2. Nights
In the earlier period (blue), nights in the warmer half of the year, and in midwinter warmed at about 0.1 degrees per year. There was no warming either in midsummer or in the warmer part of winter.
In the later period (red), it was now in the cooler half of the year that nights warmed at about 0.1 degrees per year. Nights in the warmer part of summer cooled more and more rapidly as they approached midsummer, where the cooling rate was 0.25 degrees per year.
[The 50-year average warming of this part of australia is 0.015 degrees per year. That is, less than two tick-marks on the y-axis.]


Prior postings

This graph and its commentary appeared as a post in “weatherzone” forums on 25/10/12:

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January 2016: moist again

Photo of Senna-bush

Jewel-box Cassia

Unlike December, this month saw varying temperatures. The week around the 7th was quite cool. The maximum on the 3rd reached only 22.3°, but worse was to come. The 15th reached only 21.1°: equal coldest January day in the new century (with 31/1/2001). It was more than 12° below normal, and that happens less than once in a year. There was also one very hot day above 40°, which is the normal number for January.
Rain fell, mainly as showers, on ten days spaced through the month. The higher readings were 28.4 mm on the 6th, 24.2 mm on the 23rd, and 27.6 mm on the 24th.

Weather log January 2016.

 Comparing January months

Like January last year, this month could be called “moist”. It was cloudy, and the rather cool days were only 14° warmer than the nights.
The total rainfall of 104.7 mm was well above the average of 87 mm, and in the 72nd percentile. Again, there are no serious rainfall shortages for totals for any number of months. In fact, totals for 2-, 3-, 4-, 5-, and 6-months are very high.

El Niño

Manilla’s climate is now out of step with the El Niño – Southern Oscillation (ENSO). This “super” El Niño has not brought dryness here, and the dryness in January 2014 (for example) came at a time without an El Niño.

Climate for January 2016


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 January 2016

Parametric plots of smoothed climate variables at Manilla
“January 2016: moist again”

Trends to January 2016

January raw anomaly data (orange)

In January 2016, raw values for nearly all anomalies moved well towards the cool and moist corner of the graphs.

 Fully smoothed data (red)

In the latest month with fully smoothed data (July 2015) anomalies were quite small, but were moving towards warm and dry. Partially smoothed data points for more recent months show that the warm and dry “El Nino” influence on values around October and November was smaller than it seemed at first. In particular, rainfall did not go below the “normal” range, but the anomaly of daily minimum temperature rose quite high.


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.

December 2015: normal month, normal year

Senna bush photo

Senna-leaf circles

Very few days or nights were more than four degrees from normal this month. The coldest day (the 23rd) was 24.9°, only 7.6° below normal.
Rain fell, mainly as showers, on nine days spaced through the month. The highest reading was 31 mm on the 10th.

Weather log December 2015

 Comparing December months

Nearly all climate variables were very close to normal. Those furthest from normal were:
Early morning dew point, 9.4°, below normal by 3.9°;
Daily minimum temperature, 17.1°, above normal by 0.7°;
Cloudy days percent, 45%, above normal by 14%.
The total rainfall of 101.9 mm was well above the average of 74 mm. It was almost the same as in last December (99 mm): in the 74th percentile, The two-month total for November and December was also high (176 mm). There are no serious rainfall shortages for totals for any number of months.

Climate for December 2015

The Year 2015

Compared to other years in the new century, this year had day temperatures that were on the average (25.6°), and nights (10.8°) that were just 0.6° above average. The subsoil temperature (20.1°) was also near average.
Like last year, the percentage of mornings with more than four octas of cloud (37%) was close to the recent average (40%) for 2007 to 2014, but much more cloudy than the earlier average (26%) for 2000 to 2006.
The rainfall, 621 mm, was only 31 mm below the long-term rainfall average of 652 mm.


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 December 2015

Parametric plots of smoothed climate variables at Manilla
“December 2015: moist”

Trends to December 2015

December raw anomaly data (orange)

In December, raw values for daily maximum and daily minimum temperature anomaly, which had been very high in October and November, returned to normal. Rainfall and cloud became higher than normal.

 Fully smoothed data (red)

In the latest month with fully smoothed data (June 2015) no anomalies were changing much. Most were near cool/moist climate peaks (towards the lower left): only daily minimum temperature and subsoil temperature were near warm/dry peaks. None of these peaks had extreme values.


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.

Warm Spring 2015

 

View of Redjack Mountain from Manilla

Redjack Mountain

After cool spells in early and late September, the season was marked by two long very warm spells in early October and late November. In these, days were five degrees above normal, the air was very dry, and there was little cloud.

Weather log for spring 2015

On the average, the season was only the fourth warmest spring of the new century. Spring days had been much warmer in 2002 and in 2014, while spring nights had been just as warm in 2002, 2005, 2009, and 2014 as in 2015.
Measures of moisture (rainfall, humidity, cloud, and a narrow daily temperature range) were a little below normal, but not as low as in the last three spring seasons. Humidity (as dew point) had been extremely low in spring 2013.
The total rainfall for the season, 125 mm, was in the 31st percentile. Just four years ago, the spring rainfall total for 2011 was the record-breaking 431.7 mm.

Climate for spring 2015


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

November 2015 had warm days and nights

Photo of seeding clematis

“Old Man’s Beard”

By the last week of October, the weather had cooled down to normal. In November, this continued until the 15th, with rain falling on eight of the days. The highest rainfall reading was 30.0 mm on the 5th.
After that, the weather was fine. Both days and nights were warm, but no day got to 40°. The weekly average temperature reached about four degrees above normal, as it had done early in October.

Weather log November 2015

 Comparing November months

This was a warm November, by day and by night. However, November 2014 had been hotter, and November 2009 very much hotter. The average daily maximum temperature in November 2009 (34.3°) was nearly 3° higher than in this month (31.5°).
Moisture indicators for this month were close to normal, although there was not much cloud. The dew point is no longer very low, as in the last three Novembers.
The rainfall of 73.8 mm was above average, in the 63rd percentile. The climate graph still includes the phenomenally high rainfall of November 2011: 242.9 mm, the highest November rainfall since the record began in 1883. (The next highest was 226 mm in November 1961.)
There are now no serious shortages in rainfall totals for ANY number of months. For the last 30 years, Manilla has enjoyed rainfalls close to normal. The 30-year total of 19,449 mm to this date is within 100 mm from the median 30-year total of 19,360 mm. In all that time, the most extreme major rainfall events were the 2002 winter-spring drought, and the 2011-2012 summer deluge.

Climate for November 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.