May 2019 had the warmest nights

Keepit Dam boom, May 2019

The month began warm, with the night of the 2nd being, at 18.0°, the warmest May night of the new century. There was a second warm spell nearly four degrees above normal about the 20th.
The first frost (by my reading) came on the 12th of May this year, and on the 15th of May last year. The middle date of first frost is May 13th.
There were three rain days (usually four) but nearly all the rain (61 mm) was recorded on the 4th.

Weather log May 2019

Comparing May months

The mean temperature this month (14.6°) was high, but not as high as in May 2007 (15.1°). However, the mean daily minimum temperature (8.1°) was the warmest for May in the new century: above normal by 2.3°.
A rather narrow daily temperature range (13.1°) and high percentage of cloudy days (45%) showed moisture above normal.
The (estimated) rainfall total of 61.8 mm was very high, in the 75th percentile. Because no rain at all had fallen in April, the total for the two months together reached only to the 26th percentile.

Climate for May 2019

Drought

The on-going unprecedented drought is reported in another post.


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.  Since no 9 am readings have been recorded since August 2018, I have substituted my non-standard gauge readings for all days.
All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

No Rain Days in April 2019

Split Rock Reservoir 4-5-19

A warm spell in the third week was 4.2° above normal. There were 29 days over 25°, many more than usual. Anzac Day (25th) was sunny, calm and warm. It reached 28.2°, which was four degrees above average for that day, but not up to the 28.7° of Anzac Day 2002.
There were no rain days (usually four) and the dew point on the 28th reached a record low April value of minus 3.2°. There were no frosts.

Weather log for April 2019

Comparing April months

This month was warm (average 19.8°), but not as warm as April 2018, 2016 or 2005. The mean daily maximum of 27.8° was well below that of April 2005 (29.5°).
There was no rain, as in April 1912, 1925, 1942 and 1971. Dry air was shown by early morning readings of low dew point (5.8°) and very low relative humidity (67%). However, normal moisture was shown by 30% cloudy days and a daily temperature range of 15.9°.

The last seven April months

Drought

The on-going unprecedented drought is reported in another post.


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.  Since no 9 am readings have been recorded since August, I have substituted my non-standard gauge readings for all days.
All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

Warm, Dry February 2019

Photo of bushfire smoke at 40 km.

Bushfire at Warrabah

The month began warm, with weekly temperature three degrees above normal, but it ended slightly cool. Day and night temperatures remained near normal. The highest maximum was just under 40°.
The morning of the 13th had very dry air, with a dew point of only 1.7°. (Serious bushfires were burning that day.)
There were only 2 rain days (usually 7). Neither recorded as much as 7 mm.

Graphical log for Feb 2019

Comparing February months

After the extreme heat of January, February was only 1° warmer than normal, by day and by night.
Two indicators of moisture, cloudiness and daily temperature range, were normal. However, the mean early morning dew point, 9.2°, showed the lowest February humidity this century.
The monthly rainfall of 10.6 mm was at the 9th percentile, far below the average (67 mm). This was the 12th driest February, but it had more rain than either February 2017 (6th driest) or February 2015 (ninth driest).
I have reported the on-going drought in another post.

The last 7 February months


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.  Since no 9 am readings have been recorded since August, I have substituted my non-standard gauge readings for all days.
All other data, including subsoil at 750 mm, are from 3 Monash Street, Manilla.

Spring 2018 warm

Native vine blossoms

Wonga wonga in spring

This spring was marked by very high temperature in the first week of November. Both days and nights were about five degrees above normal, as hot as expected in mid-summer. Less extreme warmth also occurred in the second half of October and in the second week of September. Periods of very dry air (marked “ARID”) came in mid-September, late November, and at the time of very high temperature.
There were 23 rain days (normally 19), but there was one rainless period of 17 days in September. No day had more than 17 mm of rain.

Weather log spring 2018

The season’s rainfall of 114 mm was at the 24th percentile, about 50 mm below average (166 mm). [The highest rainfall on this graph, spring 2016, is only 45 mm above average.] Other measures of moisture this spring (cloud, dew point, and low daily temperature range) were similar to those of spring 2017 and 2016. They were much moister than those of spring 2013.
The season was warm, with days 0.5° above average and nights 1.5° above average. Spring 2016 had been three degrees cooler. The subsoil temperature was below normal, as it was in the three previous spring seasons.

Climate for spring 2018


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. Station 55312 recorded no readings in spring 2018. I used my own readings for the whole season.

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

May 2018 third driest

Sunset clouds

the heavens’ embroidered cloths

Temperatures did not stray far from normal. The first (black) frost that I observed was on the 15th, near the normal date for it (13th May). That began a week of sunny skies and very dry air.
There was only one rain day. An early morning shower gave a reading of 1.2 mm on the 30th.

May 2018 weather log

Comparing May months

The May months in 2018, 2017, and 2016, as well as in 2014, were all warm. The average temperature was more than half a degree above the normal value of 13.3°. While May 2017 was warm, wet, and humid, May 2018 was warm, dry, and arid. The air was exceptionally dry, with the mean early morning dew point (0.0°) the lowest for May, and the relative humidity at that time 68% instead of the usual 80% to 90%.
The rainfall total of 1.2 mm was third driest for May, equal with May 2002, but not as dry as May 2006 ( 0.2 mm). Only May 1927 was drier, with zero. May rainfall values have been low in the 21st century, with an average of 23 mm, compared to the long-term average of 41 mm.

Climate in May months

Rainfall Shortages

Last month, April 2018, had only two rainfall shortages classed as “serious” (below the 10th percentile): those for durations of five years and six years. Since then, more shortages have appeared. Those five-year and six-year shortages remain, but there are now serious shortages for durations of five months and twelve months, and severe shortages (below the 5th percentile) for one month, two months and three months. The current three-month total (45 mm) is at the 4th percentile.


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.  The gauge, which had last reported on 24 September 2017, came on line again on the 16th of March. However, during the month of May eleven daily readings were blank. I have substituted my own gauge readings, which were all zero.

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