Thursday 28th August
The rain gods gave Marlborough a miss on Wednesday from the very heavy showers that drifted in on a south-westerly breeze, one sailed along the Pewsey Vale and another major storm arrived over Swindon with thunder and torrential rain mid-afternoon. However, there were several light showers and drizzle during the daylight hours that amounted to 2.2mm, which dampened the surface but no use to gardeners. The unsettled weather and variable cloud meant that temperatures were depressed with a maximum of only 20.6C at 17.35 in late afternoon sunshine. This was the lowest maximum for a week being 1.5C below average. As the skies cleared in the evening the thermometer dropped very low for August registering a minimum of 6.8C at 06.19 early Thursday, just after sunrise in Marlborough at 06.13, being 4.4C below my long-term average.
Thursday arrived with welcome sunshine after sunrise in a blue sky with thin, high cloud and vapour trails. However I observed at 07.00 thicker cloud edging our way. The temperature had recovered to 14.4C by 08.00.
The recent depression is still parked just north of Northern Ireland and continues to dominate our weather. In fact today is likely to bring us more showers on a gusty southwesterly breeze that will become more frequent and likely heavy as the temperature rises during the morning. The rain radar at 06.30 already showed a rash of showers drifting in across the West Country and heading our way. The depression is forecast to drift closer to the UK on Friday, over Scotland, that will likely mean less shower activity than today and lighter winds with the wind eventually veering into the west as the morning progresses.
When the sun heats up the air in these unstable weather conditions, under a moist Atlantic airstream, the air rises as it expands under the heat of the sun, it then begins to cool at higher altitudes. At that point the moisture within it condenses and often arrives below as showers, when the rain drops are too heavy to be contained within the cloud.
Note: The live display for rainfall has shown the amount from February, when the new on-line station became active. At last I have discovered how to include the amount from January, as a result the rainfall total now shows the total precipitation from the 1st January.
I continue the floral images from Funchal in Madeira, which is volcanic, green, rugged with high cliffs and pebbly beaches.
