Spring 2017 slightly dry

Photo of a Persian silk tree at Manilla NSW

Persian silk tree

Each year, the weather warms by about eight degrees during the three months of spring. This time, the warming came all at once. After cold nights at first, by the third week of September both days and nights were five degrees above normal. As extremes, one day reached 34° and one night 22°. After that, the temperature rose no higher through to the end of the season. By then, such temperatures are normal.

For much of the season, the air was dry, but a humid spell in October brought 63 mm of rain within four days. The season’s rainfall of 134 mm was at the 40th percentile, about 30 mm below average. Other measures of moisture were slightly low.

Graphical weather log for spring 2017

Air temperatures were near normal, with days slightly warm and nights slightly cool. Spring last year had been two degrees cooler, and spring 2014 two degrees warmer. The subsoil temperature was more than a degree below normal, as it often has been in the last two years.

Climate for spring 2017


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. That gauge failed (again) on the 25th of September 2017, and later readings are from my non-standard gauge.

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

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Cool spring 2016

Photo of a wildflower

Nodding Chocolate Lilies

Through September, days were very cool, making for a narrow daily temperature range. Then, through October, both days and nights were very cool. In November, days and nights were nearer to normal but, in contrast to September, the daily temperature range was wide. The dew point failed to rise during the season, making the air very dry in November.
Rain fell frequently up to the middle of November, then ceased. There were 24 rain days, when there are normally 19 in spring. The highest reading was 28.8 mm on the 14th of September. The season total of 216.4 mm was rather high, in the 77th percentile.

Graphical log for spring 2016
All temperature measures were below normal by 1.5° to 2.0°. Only spring of 2001 had low values like that but in 2010 the mean daily maximum (only) was 2.5° below normal.
Measures of moisture were near normal, with cloud, rainfall, and daily temperature range on the moist side, and dew point on the dry side.

Climate for spring 2016


Data. Rainfall figures for this season began from the automatic rain gauge at Manilla, published on the internet by the Bureau of Meteorology as Station 55031. That gauge ceased reporting 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.

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.

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.

Spring 2013 hot and dry

 

Weather log spring 2013.Through most of this spring season, days were hot and sunny, and the humidity and dew point were very low. This changed for the final three weeks, when two-thirds of the season’s rain fell, and the weather was cool and humid.
Along with 2002 and 2009, this was one of three hot springs this century. However, this spring had cooler nights. The springs of 2002, 2012 and 2013 were the driest, counting humidity and cloud as well as rainfall. This spring had the lowest humidity by far, and last spring the second lowest. Low humidity means crops and animals (and people) need more water.
The total rainfall (130 mm) was in the 36th percentile for springs. Rain fell on only 13 days: more than in spring of 2002 (9 days), but fewer than in 2003 (15) or 2012 (16).Climate spring 2013

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.

Droughty Spring 2012

Weather log Spring 2012.Temperatures rose as normal this spring, apart from a quick rise in the last week and a cold spell in the second week of October. In the cold spell, one day failed to reach 14°! Rain fell nearly every week, but never more than 15 mm in a day.

After last spring’s record-breaking 432 mm rainfall, this spring was about as droughty as spring 2002. The rainfall total, 81 mm, was a bit higher than in spring 2002 (66 mm) and the percent of cloudy mornings higher (25% vs. 19%), but the dew point (humidity) was much lower (3.7° vs. 5.4°) and the daily temperature range was higher (17.9° vs. 17.1°).
Showers in the last days lifted the total rainfall (81 mm) to the 10th percentile for springs.Climate spring 2012.

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.

Spring 2011 the wettest by far

 

Weather log spring 2011This spring’s rainfall of 431.7 mm far exceeded that of any other spring in the record from 1883. Winter had been very dry, with only 55 mm. While there was a lot of rain in September (91.4 mm) and October (97.4 mm), much more fell in November (242.9 mm), mainly in the second half.
The only other springs with more than 300 mm were in two small groups: 1916 (326 mm) and 1917 (327 mm); and 1949 (330 mm), 1950 (379 mm), 1954 (319 mm) and 1955 (321 mm).
Apart from the extreme rainfall, all other weather readings this spring were normal. By contrast, spring 2009 had been warm and sunny, and spring 2010, cool and cloudy.
During the season, there were two very cool spells, early in September and very early in October. They were separated by a sunny warm spell with very low humidity: it had people changing into summer gear (then back again!). By mid-November, both days and nights were very warm, but then returned to normal.Climate spring 2011

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.