Category Archives: Monthly weather

July 2008: more cloud, less frost

Posted in Manilla NSW, Monthly weather by

The daily weather log

Weather log July 2008

With 52% cloudy mornings, this was the cloudiest July (and the fifth cloudiest month) in a decade.
There were no long warm or cold spells, so the seven-day mean temperature scarcely changed until the cooler final days. Yet each day’s temperatures were quite different from the day before. Wednesday the 9th was the 4th coldest day of the decade. It reached only 9.8°, and Monday the 28th, at 11.3°, was not much warmer.
Five nights were warmer than 8°. They were separated by cold nights, but there were only fourteen frosts, the coldest, on the 12th, being 2.7°. Widespread fog on the 15th did not lift until 11 am, and there was thick fog in the valley on the 26th.
Eight rain days were scattered through the month. The wettest day had 9.4 mm, and the total was 33 mm.

 Comparing July months

Climate July 2008

The mean daily maximum and daily mean temperatures for the month were normal but, on the average, nights were warm. As a result, the mean daily temperature range, 13.6°, was the narrowest in ten July months. Sunny, frosty, droughty July 2002 had a range of 18.5°: more than 30% wider! (The month with the narrowest mean temperature range for the decade was June 2007, with 10.9°. That was also the cloudiest month.)

July usually has about 17 frosts. This month’s total of 14 made it the least frosty July this century. July 1999 had only 13 frosts, with none below -2°.
Humidity (early morning dew point) was normal for the time of year.
The rainfall total is not far below the average: 33 mm is in the 46th percentile for July. The total for this June and July together (98 mm) is better than usual: in the 52nd percentile of two-monthly totals. Not so good are the three-monthly total (112 mm) in the 30th percentile and the four-monthly total (132 mm) in the 20th percentile. Worse, the five-month total (134 mm) is only in the 8th percentile, due to the 2 mm rainfall of March. The six-month total is much better (in the 29th percentile). Rainfall totals for longer periods are normal.

Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Dew point values before August 2005 are from Tamworth Airport 6 am data supplied by the Bureau of Meteorology. Temperature and other data are from 3 Monash Street, Manilla.

 

June 2008 warm, with rain

Posted in Manilla NSW, Monthly weather by

The daily weather log

Weather log June 2008

Most of June was very warm. The 7-day average temperature stayed three degrees above normal for the first three weeks. All five rain days came during that time. The first, with 38.2 mm, was the wettest June day in a decade. By the 4th of the month the average rainfall for June (44 mm) had already been beaten. Sadly, the total rose only to 65.2 mm, the same as last year. Around the rainy days the nights were about 7° warmer than usual, and humidity was high (morning Dew Points near 10°). There were frequent fogs, including one on Saturday the 7th that was widespread and thick, and lasted a long time.

The fourth week saw a return to normal June temperatures, with sunny cloudless days. Frosts came back, but there were only eight altogether instead of the usual thirteen.

 Comparing June months

Climate June 2008

This June was warm and humid. However, due to the cool, dry change in the fourth week, it was no warmer or more humid than June of 2005. The graph shows that June 2005 had very high rainfall. It was the sixth wettest June on record.

While this month had more cloud than usual, June last year was much cloudier, and had bitterly cold days – nearly five degrees colder! By contrast, sunny June 2006 had very cold nights, including 21 frosts.
The rainfall total of 65 mm is high. It is in the 78th percentile for June, and nearly twice the median value (36 mm).
The rainfall total for this May and June together (79 mm) is in the 38th percentile of two-monthly totals, while the three-monthly total (99 mm) is in the 23rd percentile. Being above the tenth percentile, these do not count as “serious” shortages of rainfall. The four-month total (101 mm) is a serious shortage: it is only in the 9th percentile. The five-month total is much better (in the 35th percentile). Rainfall totals for longer periods are all normal, that is, near the median.

Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Dew point values before August 2005 are from Tamworth Airport 6 am data supplied by the Bureau of Meteorology. Temperature and other data are from 3 Monash Street, Manilla.

 

Perfect May weather in 2008

Posted in Manilla NSW, Monthly weather by

The daily weather log

Weather log May 2008

The mean daily temperature rose to a normal value by the middle of the month and then tracked down along the usual curve. Daily maxima were near normal except for one cool Sunday. Daily minima were also normal, except for a warm night (12°) on the 16th and six mild frosts.
The second week had very dry air, but the third week was humid, with four days of rain showers totalling 14 mm. A  number of cloudy days produced no rain.

 Comparing May months

Climate May 2008

The weather for May was normal in all respects: maximum, mean, and minimum temperatures, humidity, cloudiness, and rain. Some of us would call it perfect weather!
Normal temperatures break a five-month spell of unusually cool weather. On the other hand, as the graph shows, this month is much cooler than May last year. Six frosts is the normal number for May, and compares with 3 last year and 14 the year before.
Humidity, indicated by early morning Dew Point, is similar to that in 2004 and 2005. It had been higher early in the decade, due to moisture from “La Niña”.
At 14 mm, this May’s rainfall is not very low. Being well below the May average (40 mm) does not mean much. In Manilla, rainfalls in the months of March, April and May are highly “skewed” so that the very lowest rainfalls are the most common. Rainfalls of 5 mm or less occur often – more often than one May month in eight (There are two on the graph!). Fourteen millimetres is in the 25th percentile of May rainfalls.
The rainfall total for this April and May together (34 mm) is in the 9th percentile of two-monthly totals (a serious shortage) and the three-monthly total (36 mm) is in the 2nd percentile (a severe (almost extreme) shortage). The four-month total is better (in the 28th percentile) and the five-month total better still (in the 35th percentile). The six-month total (summer plus autumn) is high: in the 61st percentile. Beyond that, the totals for 9, 12 and more months are all normal, that is, near the median.

Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Dew point values before August 2005 are from Tamworth Airport 6 am data supplied by the Bureau of Meteorology. Temperature and other data are from 3 Monash Street, Manilla.

 

April 2008: fog and black frosts

Posted in Manilla NSW, Monthly weather by

The daily weather log

Weather log April 2008

Usually, the air cools and dries out quickly during April. This time only the daily maximum temperature came steadily down. The average temperature hovered near 16° until the last days.
At first, the air was very dry, with a Dew Point below 5°. Under a clear sky on the 4th the early morning temperature went down to 2.1° in the screen, which would be 0.1° of frost. Because the Dew Point (-3.8°) was much lower than that, there was no ice on the grass, which made it a “black frost”. It is said that frosts seldom occur in Manilla before ANZAC Day (April 25th).
As the month went on the air got moister. By the 24th the clouds in the overcast sky were down on the hills. On the 26th the town was blanketed in fog as the humidity hit 100%. (Temperature and Dew Point were both 8°.)
Evaporation was increased by strong winds on the 27th and 28th.
Dry southerly air made the last three days cool and sunny. Black frosts came back giving screen temperatures of 0.6° and 0.1° (around 2° of frost).
Practically no rain (3.6 mm) fell in more than seven weeks from 29 February to 21 April. After that, there were four rain days, including 12.8 mm on the 24th. In total, 20.2 mm fell in April, on five rain days.

 Comparing April months

Climate April 2008

The mean temperature this month was nearly as low as the coolest  April in ten years (1999). This was the fifth cool month in a row: December (1.0° down)  January (1.9° down) February (3.1° down) March (0.9° down) and April (2.1° down). As a 5-month average the temperature was 1.8° below normal. It is as if Manilla had been moved 400 km south (near Grenfell) or 150 metres higher (like Barraba). (Note added: This was a time of global low temperature.)

The month was as cloudy as usual, but less humid.
At 20 mm, this April’s total rainfall is about 20 mm below average, as in 2001 and 2004. It is much higher than in April 2005, when Manilla was in a rainfall  drought for several months.
The rainfall total for this March and April (22 mm) is in the 4th percentile of two-monthly totals: a severe shortage. However, the three-month total (138 mm) is just below the median, and the totals for 4, 5, 6, 9 and 12 months are all at the median or above it. In particular, the 6-month total (401 mm) is quite high, at the 75th percentile.

Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Dew point values before August 2005 are from Tamworth Airport 6 am data supplied by the Bureau of Meteorology. Temperature and other data are from 3 Monash Street, Manilla.

 

Dry, Dry March 2008

Posted in Manilla NSW, Monthly weather by

The daily weather log

Weather log March 2008

After 115.6 mm of rain in February, March crashed to just 2.2 mm with only three rain days. In 1971 it was worse: that year February had 173 mm and March 1 mm!
This month the air was very dry, too. Morning Dew Points which had been quite low (10°) all month, plunged to zero or less in the last days.
Although there were six cloudy mornings, eighteen mornings were completely cloud-free. The whole of the summer had only thirteen free of cloud!
Due to the dry, fine weather, three-quarters of the days had a range of temperature higher than the normal value of 15.4°. Three days had a range of 21° or more.
The 7-day average temperature began and ended well below normal, but was above normal in the third week. Nights were cold (8° below normal) in the first and last days.

 Comparing March months

Climate March 2008

The mean daily maximum temperature this March (29.9°) is normal, but the mean daily minimum (12.2°) is the lowest in ten years. It is 2° below the average, and 4° below that of 2007 (and 2000).
The mean morning Dew Point, 8.8°, is 3° lower than normal for March. This shows very dry air, which is wilting many shallow-rooted plants.
The total rainfall of 2.2 mm is much lower than the other Marches on the graph. It is not very low compared with Marches in the long-term record: it is on the 6th percentile. In Manilla, rainfall varies more in March and April than in other months.
There must be a lot of water deep in the soil. Total rainfalls for the last 2, 3… 18 months are all above the median. The four and five-month totals are particularly high, in the 83rd percentile.

Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Dew point values before August 2005 are from Tamworth Airport 6 am data supplied by the Bureau of Meteorology. Temperature and other data are from 3 Monash Street, Manilla.