Friday 11th September
Thursday was a pleasant sunny day with the thermometer rising to 19.2C at 13.07 being 0.2C above average. More cloud drifted across in the afternoon also the wind became quite gusty, hence no further rose in temperature. This was due to a couple of warm fronts crossing the UK with their associated cloud. During the evening a couple of very weak, fragmented bands of showers crossed the country that amounted to just 0.8mm. The slightly warmer air behind the warm front, combined with total overnight cloud cover, resulted in a minimum of 13.7C at 05.42 early Friday being 4.2C above average.
Friday after first light revealed low cloud draping the tops of the Marlborough Downs from the back edge of the last weather front and no sunshine. However, a weak cold weather front is heading south that could thicken cloud cover around midday. Hopefully, the clouds might thin and allow a little sunshine to break through that could then lift the maximum above average. The breeze has veered into the northwest that is a slightly drier airstream.
Saturday will be a much brighter, sunnier day as a ridge of high pressure will continue to push back across the country squeezing out any shower activity. Sunday is likely to be a significant contrast with much more cloud and possible light precipitation during the morning.
When does astronomical autumn begin?
Astronomical autumn begins with the autumn equinox, which usually falls on 22 or 23 September each year. During the equinox, the Sun shines directly above the Earth’s equator, resulting in day and night being nearly equal in length across the globe.
Unlike meteorological seasons, astronomical seasons are determined by the Earth’s position in its orbit around the Sun. Because the Earth’s orbit is not perfectly uniform, the exact date of the equinox can vary slightly from year to year.
After the autumn equinox, nights become longer than days in the Northern Hemisphere, continuing until the spring equinox the following year.