January 2015: cool rainy days

Crepe myrtle shrubs

Crepe Myrtles in Arthur Street

Only five days were warmer than average. The final five days and four nights were very cool, taking the weekly average (normally the hottest of the year) down to five degrees below normal. (This would be normal for the end of March, not January!) There were fifteen rain days, equalling the 125-year record number for January, set in 1941. Rain was spread evenly through the month, with the highest reading 29.2 mm on the 2nd.

Weather log January 2015

Comparing January months

The mean daily maximum temperature (31.4°) was well below the average of 33.8°. Since nights, at 17.6°, were near normal, the daily temperature range was the record narrow value for January of 13.8°.
The dew point (humidity) returned to a normal value of 12.9°, after last January’s arid 6.9°. Subsoil temperature (25.3°) fell to normal after two January months above normal.
The total rainfall of 117.4 mm was in the 75th percentile, well above the average of 87 mm. This clears all shortages in rainfall totals for groups of months. The lowest percentile value remaining (15th) is for the 18 month total of 746 mm.

Climate for January 2015


Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Temperatures, including subsoil at 750 mm, and other data are from 3 Monash  Street, Manilla.

3-year trends to January 2015

Parametric plots of smoothed climate variables at Manilla
“January 2015: rainy cool days”

Trends to January 2015

 

January raw anomaly data (orange)

Anomalies for all variables except subsoil temperature moved across the graphs, from “droughts” in November to “flooding rains” in January. Subsoil temperature had been normal from February to December (11 months!), then became cooler than normal in January.
Most raw anomaly values for January were close to the fully-smoothed anomaly values of the La Niña-affected cool summer of 2012. This month’s daily temperature range was even narrower, and the subsoil temperature lower, but the daily minimum temperature was not so low.

Fully smoothed data (red)

The latest fully-smoothed data anomalies (July 2014) were near normal. (Dew point, like most recent values of that variable, was 3° lower than normal.)


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 2014 rainy with warm nights

Photo of a rain-shower

A shower on Mt Baldwin

Few days or nights were unusually warm or cool, except for a very cold day on the 28th. Thunderstorm clouds were often seen, but only a few yielded any rain. Later, overcast skies brought steady rain recorded on the 27th (25.2 mm) , 28th (11.2 mm) and 29th (12.6 mm). There were fourteen rain days: twice the usual number.

Weather log December 2014

Comparing December months

The mean daily maximum temperature (31.8°) was normal, but the mean daily minimum temperature (18.0°) was very high (Very warm nights!), just below the record of 18.6° set in 2009.
Subsoil temperature (24.7°) fell to normal after two Decembers above normal.
The total rainfall of 99.0 mm was in the 72nd percentile, well above the average of 74 mm. This clears most of the shortages in rainfall totals for groups of months. Two serious shortages remain: the nine month total of 306 mm is in the 8th percentile, and the eighteen month total of 659 mm is in the 6th percentile.

Climate for December 2014

The Year 2014

This year had the warmest nights (11.34°) of the new century. Although the days, at 26.67°, were cooler than in 2002 (26.72°), this year had also the warmest mean temperature: 19.01°. The second-warmest, at 18.85°, was 2009 and the coolest, at 17.19°, was 2008.
The subsoil temperature: 20.5°, fell back to near average.
In the year, 39% of the mornings were cloudy (more than four octas of cloud). This is 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, 447 mm, was second lowest in the new century, after 2002 (366 mm). In the long-term rainfall record, this is a serious, but not severe deficiency: it is in the 8th percentile.


Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Temperatures, including subsoil at 750 mm, and other data are from 3 Monash  Street, Manilla.

3-year trends to December 2014

Parametric plots of smoothed climate variables at Manilla
“December 2014 rain again”

Trends to December 2014

December data (orange)

From November to December, the raw anomaly value for daily maximum temperature returned to normal from extremely high. Rainfall anomaly moved from very dry to rather wet. Most other anomalies came back to near zero, where they had been (as smoothed values) in June 2014, six months earlier.
Temperature range became low while daily minimum temperature remained high. (Which causes which?)

Fully smoothed data (red)

The latest fully-smoothed data (June 2014) mainly show a renewed movement towards drought.


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.

Spring 2014 dry and hotter

Weather log for spring 2014

Warm weather developed in early October, followed by a cool spell with one rain day of 26.4 mm. After that came three hot spells. There were showers and storms in the district, but little more rain fell at Manilla.
This spring was slightly hotter than spring 2013 and spring 2009, but not as hot as spring 2002. The air was not as extremely arid (dew point 3.6°) as in last spring (dew point 2.3°), and skies were a little more cloudy.
The total rainfall of 69.8 mm was in the 8th percentile: the 10th lowest spring rainfall. (Spring 2002 had been equal 5th lowest at 66 mm, and spring 1957 the lowest at 23 mm.) Rain fell on 11 days: more than in spring of 2002 (9 days), but fewer than in 2013 (13).

Climate for spring 2014


Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Temperature, including subsoil at 750 mm, and other data are from 3 Monash Street, Manilla.