March 2016 had a warm dry spell

Photo of Pittosporum berries

“Native Apricots”

In the first half of March the average weekly temperature was more than three degrees above normal. Nine days had maxima above 35°, when the month usually has only one. However, no day reached 40°, as happened in March last year (20/03/15).
No rain fell in this time: the period of 43 days between February 4 and March 19 may have been the seventh longest rain-free period in 133 years. (No official record is now kept.)
Normal weather returned in the second half of the month. I recorded 20.8 mm of rain on the 19th, and further rain on the 30th and 31st.

Weather log for March 2016

Comparing March months

Despite the cool change, this was the warmest March of the new century. Daily maxima, minima, and means were all 2° above average. The subsoil temperature was also 1° high, as in March 2012 and 2013, but not as high as in 2007 (2° high).
This was not a dry month. The moisture indicators cloudiness, humidity, and (low) daily temperature range were just slightly on the dry side.
The total rainfall of 35mm was below the average of 53 mm, but in the 46th percentile, not far below the median. Again, there are no serious rainfall shortages for totals for any number of months. In fact, the five-month total of 362 mm is high, in the 81st percentile. Ponds persist in Greenhatch Creek.

Climate graph for March 2016.


Data. All data, including subsoil at 750 mm, are from 3 Monash Street, Manilla. Rainfall data up to 26/3/15 is from Manilla Post Office, Station 055031.

No rain, and no rain gauge

A very long spell with no rain

My town, Manilla NSW, may be having one of the longest periods without rain in 133 years. We will never know.

The records of the Manilla Post Office rain gauge, No. 055031, show that the longest periods without rain were as follows:
1. August 1946: 62 days;
2. April 1912: 55 days;
3. Apr-May 2002: 47 days;
4. August 1914: 46 days;
5. May 1927: 45 days;
6. Mar-Apr 1980: 44 days;
7. April 1925: 43 days;
8. August 1982: 42 days;
9=. March 1896: 41 days;
9=. August 1995: 41 days;
To judge by my rain gauge, we have had a rainless period that is already equal seventh longest since 1883. Today, rain bands are passing through, but perhaps no rain will fall in my gauge. There may be several rainless days yet.

My gauge not valid for Manilla

Photo of dry wedge-type rain gauge

My rain gauge

The photo shows my personal rain gauge. It is dusty because it has been dry for the last 43 days.
Whether it rains in my gauge today or not, my reading cannot count in the record for the town of Manilla. It is as if it is this dry spell is not happening.
My gauge is very simple and not precise. It is hard to read to parts of a millimetre. I bought a cheap one, because there is no point in having a precise rain gauge in my yard. The yard is too sheltered to meet the Bureau of Meteorology standard. My house is also a kilometre away from the Post Office.

Manilla’s failed rainfall record

Rainfall was first recorded at the Manilla Post Office in March 1883. The record of readings was essentially unbroken through 132 years until the 26th of March 2015. There are towns with longer rainfall records, but not very many.
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