The daily weather log
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
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.