We’re heading for record rainfall totals

The area of low pressure mentioned in my last note passed over just before midnight last night (24th). An associated warm front generated 16 hours of more or less continuous rain, from 8.30am yesterday to 1am today. During that time a total of 24.8mm of rain was recorded, with a spell of really heavy rain as the front passed by at 11.45pm.

After the passage of the warm front, the rain eased off and the centre of the depression moved off north-east. As a consequence the wind backed from East through North to South West, growing in strength as it did so. During a blustery night, the peak gust was 34.8kts at 3.26am.

Since 20 November we have recorded over 76mm of rain, and the total for November as I type this (it’s 10.30am now) is 130.8mm – with yet more rain forecast for later today. The highest monthly total recorded here is 148.8mm in November 2009, and it’s hard to predict whether that record will be broken – it is suggested that there will be a quieter spell of weather at the end of the month, so perhaps we’ll get some respite from the rainfall.

The wettest year seen here was 2008, with 904.4mm. Since we’re already up to 889.4mm for 2012, that record looks certain to fall.

A halo round the moon – signifying more rain

Today has given us a break from the wind and rain, but it’s 8pm and I have just noticed a halo round the moon. The halo is generated by ice crystals high in the atmosphere, a sign of cirrus cloud and the first indication of an approaching area of low pressure, currently sitting off the coast of Portugal.

This low is forecast to move north-east towards us, bringing yet more wind and rain tomorrow (Saturday). No doubt the drainage pumps are working hard, but the rhynes and ditches are already full and there must be a risk of more local flooding: and, with the ground so wet, another gusty day may bring trees down. Take care!

November rainfall passes the 100mm mark

At 6.20pm today November became the fifth month this year to exceed 100mm of rainfall, and there is still a week to go – a week which, the forecasters tell us, may bring plenty more rain. We can expect a few more millimetres this evening following the passage of a cold front (see previous post), and already there are warnings of heavy rainfall this weekend. Hard to believe that this year began with a drought!

Record-breaking winds – and more rain to come

Wind speeds have been rising all day as a depression passes to the north of the UK, and at about 4.45pm today an active cold front that has been crossing the country reached Brent Knoll. The temperature dropped from 13C to 9C in a few minutes, a squall line brought heavy rain and the wind rose to a maximum gust of 41 knots (47mph) – the highest recorded at the weather station since December 2008.

The passing of the front should, with any luck, see wind speeds moderating: but the rain is likely to continue, though perhaps not quite as heavily as the initial squall. With the ground already saturated and watercourses full, there must be an increased risk of flooding. There is a link to the Environment Agency’s flood warning pages for the local area under the Weather links section on the right, but there may be local flooding as well as falling trees and other debris. Take care!

The rain is back . . .

After a series of wet months, November looked set to be refreshingly normal – until now. Up to yesterday we had recorded 55 mm of rain, well within the normal range, and the weather had been an autumnal mix of misty mornings and dull days – temperatures were right on the average and there was nothing exceptional in the way of wind. Not much to write home about, really.

Then, yesterday, the rain came in earnest – first, a couple of heavy spells during the day as cold fronts passed over, giving a total of 11mm by evening. At about 9pm another slow-moving front arrived, and this is still snaking slowly across the south-west bringing continuous and sometimes quite heavy rain. The rain looks set to continue until lunchtime today, and with the ground already soaked from yesterday’s rain there is nowhere for the water to go. Local flooding is the inevitable result*.

This spell of rainfall is reminiscent of the heavy rain on 23/24 September this year, and the cause is the same: a slow-moving front with a big burden of moisture, which it deposited on us as it moved very slowly across the region. At the time of writing (10.30am) we have seen about 30mm of rain in 24 hours – that’s somewhat less than we saw in the September deluge, but still enough to cause a good deal of disruption. Moreover the ground has had yet another good soaking, so the risk of flooding will remain higher than normal.

*Edit 23 November 2012 Just discovered that the flooding included my local, the Red Cow at Brent Knoll – commiserations to Mike and staff, and here’s hoping things are back to normal ASAP!