Past Week’s Weather
The cold spell continued into the start of the week with 8 cm of snow on the ground at Brize Norton but milder air pushed across the country from the west, bringing strong winds and rain which has caused some flooding, especially when linked to the melting snow.
After a warm start to the week the wind swung more southerly bringing cooler conditions from near the Antarctic. Showers and more persistent fronts brought spells of rain, low cloud and strong winds. Over the weekend the wind, occasionally gale force, became more westerly bringing warmer weather.
Mainly dry but isolated light showers affected some parts, mainly around
Sunnier than of late but with some showers, mostly in the mornings, with cloud covering the hills at times. Some heavier showers developed later in the week, clearing somewhat over the weekend.
Rain, compiled by Rayne N Katzendogz
I mentioned that the
Another way of expressing rainfall is that 1 millimetre of rain is 1 litre (or 1 kg) of rain per square metre. So if we have 2.5 mm per hour of rain falling (this is classed as moderate rainfall) that means every hour the rain continues, a square metre of ground will have 2.5 litres of rain fall on it. If you work out how big a roof you have, you can see why gutters matter! On one day in April 1985, 145.5 mm of rain was recorded as falling at the Airhead, so in that day over 145 litres of rain per square metre fell.
As for snow, the crystals of snow take up more room than liquid water, so much so that in the
When forecasters speak of light (or in the correct form, “slight”), moderate or heavy rain, and when we talk about showers instead of just rain, we mean specific things. “Rain” technically falls from layered cloud and generally lasts for longer periods, “showers” fall from convective (column) clouds. Slight rain is up to 0.5 mm per hour, moderate from 0.5-4.0 mm/hr and heavy is over 4.0 mm/hr. A shower of rain is generally a short event but with larger amounts of rainfall and bigger rain drops so slight showers are up to 2 mm/hr with moderate being between 2 and 10 mm/hr and heavy 10 to 50 mm/hr.
“Drizzle” is a different beast again and is defined by the small size of the individual drops and how much it reduces visibility. “Drizzly showers” are not supposed to be able to exist, but (thanks to the wonderfully humid air here) are something we experience here quite a lot!