Marlborough's weather: were the first two days of August just making up for our dry July?

Written by Eric Gilbert on .

July blooms at The Lamb (photo: Eric Gilbert)July blooms at The Lamb (photo: Eric Gilbert)July 2016 was memorable for the minimal amount of rainfall. Although there were only eighteen totally dry days, there were many days with the occasional light shower.

The total precipitation amounted to 23.7mm against the mean of 61.0mm, which makes this the fourth driest July since this station started its records in 1984. The wettest day occurred on July 28 with 7.3mm - that was almost one third of the whole month’s rainfall in one day.

Marlborough's driest July was in 1999 with just 10.1mm of rainfall - and the previous very dry months were in 1994 and 1984. In the past there have been many very wet Julys with the record set in 2007 with 127.2mm.

There has been a rising trend for heavier rainfall since the year 2000, which has levelled out in recent years.

The evaporation from the ground, water sources and plant life for the month was 96.3mm giving a deficit of equivalent rainfall of almost 73mm. No wonder my six water buts ran dry looking after the greenhouse, fishpond and many flower planters! Following the below average rainfall in June, this makes the deficit for the combined months of almost 93mm.

It was not a July to remember for prolonged hot spells. The mean temperature was 0.5C above the log-term mean principally due to the night temperatures being 0.4C above the average.

There was a very warm - even hot spell - around the middle of the month when the thermometer soared to 31.7C on July 19 and with several days just before and afterwards in the high 20s. The record temperature for July was set in 2006 with a high of 34.9C.

The solar energy for the month was close to the average helped by 111 hours of strong sunshine.

The UV levels were consistently in the Very High category on 28 days in the month. The gloomiest day occurred on July 28 with a Moderate rating due to the cloud cover, which produced the wettest day.

Fog occurred during the early morning of July 18 with visibility down to 100m.

Any prolonged spell of wet weather following August's first two very wet days will be in danger of keeping the combines out of the remaining standing corn - so delaying the harvest.