Category: Commentary

Monday saw the early effect of the hot air being brought to us on a south westerly air flow from North Africa as the thermometer steadily rose ta maximum of 25.6C at 16.05, which was 2.9C above average. The humidity was high all day, around 70%, making it feel very uncomfortable, when under such heat it is around 40%.

Another dry day with the UV level at the top end of the very high category.

Overnight the thermometer dipped away to a minimum of 12.8C at 04.38, being 1C above average.

Fog formed in the early hours with visibility at 05.00 restricted to 100m.

By 08.00 the thermometer had risen to 16.6C and the fog thinned, under the influence of continuous sunshine, with visibility improving to 500m. Not surprisingly, the humidity at 08.00 was very high at 98%, the highest since 2nd February.

Update on Tuesday at 16.20: thermometer maximum of exactly 32.0C at 17.35. This was 9.3C above average and the hottest day in 2019. My weather station is on the north east boundary of Marlborough so the peak temperature in town would have been a degree or two higher.

The southwesterly breeze brought milder air with the thermometer rising to 22.3C on Sunday, just 0.3C below average. This mild, moist air continued overnight producing a very mild night with a minimum just before midnight of 15.3C, which was 3.5C above average, the warmest night since 25th June and up 5C on the previous night minimum.

Monday arrived with complete cloud cover blotting out any chance of sunshine, the thermometer having risen further to 18.3C at 08.00.

The barometric pressure has been rising over the past two days, current reading of 1021.1mb, as the ridge of high pressure intensifies with the promise of more warm/hot, dry weather.

Update on Monday at 16.20: thermometer rose to 25.6C at 16.05 making it the second warmest day in July being 2.9C above average. Humidity very high at around 70% for most of the day.

After the cloudy and wet day on Friday, Saturday saw the sun return as the barometric pressure began to rise giving us nearly 10 hours of sunshine and a much warmer day, although below average (-1.4C) with a maximum 21.3C.

It was a dry day except for a light shower mid-morning. Rainfall in July stands at 19.2mm but evaporation has risen to 70mm.

The past night was 3C cooler, and below average (-1.4C), than the previous very warm night with a minimum of 10.4C at 05.35.

After initial brightness at dawn on Sunday cloud quickly blotted out any sunshine. However, at 08.02 the cloud began to break up allowing bursts of sunshine.

Update on Sunday at 18.10: late afternoon sunshine raised temperature to a maximum of 22.3C at 17.56, just below average, with UV level rising to very high.

The first weather front (warm) on Friday produced 10.0mm of rainfall with the second weather front (cold) crossing overnight another 2.7mm thus a daily total of 12.9mm being the wettest day since 10th June when 25.1mm was recorded.

The rainfall for July has now reached 19.0mm compared to the 35-year average of 59.9mm.

The past night has been exceptionally warm with the thermometer not falling below 15.9C at 05.07.

Saturday arrived with thick cloud from the hang back of cloud, produced by the cold weather front, easing away to the east. By 08.00 the sun had begun to break through with the thermometer at that time having risen to 17.0C.

Thursday gave us another 8.8 hours of sunshine between variable cloud, which, with a brisker westerly wind rather than south west, meant a drop of 2.5C on the Wednesday peak with a maximum of 21.5C being 1.2C below average.

Overnight the thermometer fell away to a minimum of 9.9C at 04.15, almost 3C below average. This low was before cloud thickened from the advancing weather front bringing the first spots of rain just after 05.15 that by 08.00 on Friday totalled to 0.6mm.

The soil temperature at a depth of 5cm at 08.00 Friday registers 15.4C compared to the warmest morning at that depth of 22.9C on the 5th.

Update on Friday at 14.40: first weather front (warm) produced 10.2mm of precipitation during the morning.
July so far: rainfall 16mm vs. evaporation of 66mm