Category Archives: Manilla NSW

Rainy, very cloudy September 2010

Posted in Manilla NSW, Monthly weather by

The daily weather logWeather log September 2010 Manilla

 

Like August, September had no extremes. Many days had normal temperatures, especially late in the month, and many others were cool. Nights varied, with two frosts, but most were warm.
Rain fell on 11 days, a September record number for the decade. The highest reading was 22.2 mm on the 10th. A reading of 12.6 mm was due to a brief afternoon shower on the 27th.

Comparing September monthsClimate September 2010 Manilla

 

The mean daily temperature (14.9°) was normal, but days (21.5°) were only 13.3° warmer than nights (8.2°). Usually, September has the highest daily temperature range of the year: 16.9°.
Along with cool days and warm nights, there were more cloudy mornings (57%) than in any September on this record. Very high humidity made the mean early morning Dew Point (7.3°) nearly two degrees higher than normal.
The rainfall of 59.3 mm is in the 76th percentile for September, well above the long-term average of 41 mm. Totals for two, three, and four months are now all above the median. The thirty-year total has now reached the median value, after three years below it.

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.

Winter 2010 wet, with few frosts

Posted in Manilla NSW, Season Weather by

 An episode of maritime climate

I have posted this seasonal report for winter 2010 on the front page, as a sticky post, to show how the climate of that season was not normal. It was not the average temperature or the rainfall that were unusual. The sky was very cloudy, the humidity very high, and the daily temperature range very low. The climate was equable, as one would expect at a place near the sea: a maritime climate. More in the footnote*

Weather log winter 2010

Temperatures this winter changed little from month to month. June, July and August each had temperatures near the season averages: maximum 17.0°, mean 10.7° and minimum 4.5°. Warm days were rare: only 11 exceeded 20° (usually 25). This winter was even less frosty than the last, with only 32 frosts (usually 44). The lowest minimum was -3.1°.
There were 33 rain days, about twice the usual number.

In terms of daily mean temperature, this winter was normal, However, cool days and warm nights made the daily temperature range (12.5°) narrower than in any winter in the 12-year record. It was also the cloudiest, at 49% cloudy mornings. Manilla’s climate became much more cloudy three years ago, when the average number of cloudy mornings in a month jumped suddenly from nine to twelve (See also these other graphs.). Humidity, as shown by early morning Dew Point was also very high this winter. All these changes reflect a more maritime climate, as on the coast.
Each month would have had rainfall close to average, were it not for one reading of 34.2 mm at the end of July. The total of 160 mm is in the 70th percentile, like that of the wet winters of 2005 and 2007.

Climate winter 2010

*Footnote. The nature of this episode is clear on the 3-year graphs of climate trends, such as that for August 2011. The top left graph shows that, in June, July, and August 2010, rainfall was a little high and daily maximum temperature rather low. The bottom left graph shows the main anomaly: daily minimum temperature remained extremely high while daily maximum rapidly fell, reaching a record low value by October 2010. From July to November that year the difference between daily maximum and daily minimum temperature was some three degrees less than normal.
The middle graph on the right shows directly that the daily temperature range in those months was at record low (narrow) values.

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 August 2010

Posted in 3-year climate trends, Manilla NSW by

Parametric plots of smoothed climate variables at Manilla
“Summer retreated from drought”

Trends to August 2010.

Manilla’s recent climate continues to be marked mainly by cloudier skies and a narrower daily temperature range than in the 12-year averages.
In the current plots we see final smoothed trends for summer (DJF) of 2009-10.

Daily maximum temperature anomaly is shown on the x-axis of each plot. The minimum value in Feb 2008 (-1.61) and maximum value in Nov 2009 (+1.35) are also the extremes (in blue) of the smoothed data set. In summer 2009-10 the smoothed temperature anomaly fell much faster than it had risen in the previous winter and spring. During autumn the max temp anomaly was near zero, and the raw value for August is so low (cold) the scale has had to be extended.

Monthly total rainfall anomaly is on the y-axis (inverted) of the first graph. It showed a very mild drought throughout the last winter, spring, and summer. Autumn seems to have been less droughty, much like the previous autumn, but with the opposite trend. Recently, July 2010 was very wet, but August rainfall was normal.

The anomaly of per cent cloudy mornings fell during winter 2009 as the maximum temperature anomaly rose. During summer 2009-10 it rose again as the maximum temperature anomaly fell. However, for a given maximum temperature anomaly the cloudiness anomaly was now more positive (it was cloudier). Since the end of summer, skies have been extremely cloudy

On the graph for early morning dew point anomaly, the final year’s data plots like that of the cloudiness graph. However, dew point anomalies were not so positive: in winter and spring 2009 they were quite strongly negative. By autumn 2010, dew points seem normal, and recent values are high (humid climate).

For daily temperature range anomaly, again, the last year’s pattern on this graph is like that on the previous two graphs. In this case, values low on the graph are negative anomalies, representing narrow daily temperature ranges. For a given maximum temperature anomaly, the anomaly of daily temperature range was lower during the summer than it had been the previous winter.

(Note on the “Macquarie Island” label. This August  Manilla’s anomalously low maximum temperature (16.8°) is actually much higher than that of Macquarie Island (5.0°), and the anomalously narrow daily temperature range (11.9°) is still much wider than that of Macquarie Island (3.5°).)

In the case of daily minimum temperature anomaly, summer 2010 began with a maximal value, and the value stayed high through the season. Values may have been lower in autumn, then they seem to have risen even higher (very warm nights).

World-wide low temperature

At Manilla, in early 2008  there were record low values of daily minimum temperature, daily maximum temperature and subsoil temperature. These did NOT come with high rainfall and high dew point as would occur in a “flooding rains” peak of the quasi-biennial oscillation. They match low temperature at that time world-wide.

Subsoil temperature anomalies have remained close to zero for 17 months, despite big changes in the anomalies of other temperatures.

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.

Cool days in August 2010

Posted in Manilla NSW, Monthly weather by

The daily weather logWeather log August 2010 Manilla

August had no extremes. Only four days exceeded 20° (usually thirteen days), and only ten nights were frosty (usually fifteen). The subsoil temperature failed to rise during the month, ending at 13.5°, which is 1.0° cooler than normal.

Rain fell on 13 days, an August record for the decade, but the highest reading was only 10 mm.

Comparing August monthsClimate August 2010 Manilla

The mean daily maximum temperature (26.5°) was the lowest for November on this 12-year record. The mean daily temperature range (12.4°) was (with November 2008) a record low value.

Mean subsoil temperature (20.4°) was the lowest since November 1999. The month ended with subsoil temperature (then 22.2°) trailing only 10 days later than its usual date. It had begun the month 22 days late.
There were more cloudy mornings (53%) than in any November on this record.
The rainfall of 105.4 mm is in the 84th percentile for November, far above the long-term average of 67 mm. Totals for groups of months up to 15 months are now all above the median, as is the thirty-year total.

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 July 2010

Posted in 3-year climate trends, Manilla NSW by

Parametric plots of smoothed climate variables at Manilla
“Extraordinarily moist”

Trends to July 2010.

The July 2010 raw data, (orange) shows an extraordinarily moist month. Anomaly values of rainfall, cloudy days, Dew Point, and temperature range are so extreme that the graph margins have had to be moved. The Minimum temperature anomaly is also extraordinarily high, but this result is not so clearly linked to moisture.
Extreme moisture is usually associated with low maximum daily temperatures, in the “Flooding Rains” corner of the graphs, but this July the maximum temperature is not extreme, but 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.