Winter 2009 / 2010 in Western Europe?

February 2010 forecast

Summary: CET temperature 2.8C or 1.4C below average*; rainfall 90%* and sunshine 110%*

*The average February CET 1971-2000 is 4.2C, last February 4.1C, 2008 5.4C. Feb figures updated 17Z 01/02/10

Issued: 31st January 1100GMT
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Monthly retrospective for January 2010
January was again a cold month- but one of two halves. Though mean temperatures were 3C below average the first half saw them around 6C below whilst the second half was near average. N Scotland was only a degree below average though. This made it the coldest month since January 1987. Rainfall was around 75% across England and Wales but as high as 100% across SE England and the Midlands and only 55% across N Scotland. Sunshine was well above average overall at 124% and especially in the first half of the month and in western UK where 130-150% was recorded. However it was quite dull in places in the second half, especially the east, meaning Eastern Scotland saw just 88%.

The year started rather cold for most; a little less so in the south as snow fell by the 3rd, mainly across E Scotland, NE England and W Wales. Braemar (Aberdeenshire) recorded a minimum temperature of -17C on the 3rd. However the cold continued through the first week and by January 8th the coldest temperature since 1995 was recorded at Altnaharra (Sutherland) of -22.3C (and the coldest this month) with a rare snow cover across almost all of the UK. Many minor roads remained snow covered or icy. Some areas in the south (especially around Reading, Berks) had seen 30cm of level snow fall. Salt & grit supplies were "stretched" with thousands of schools remaining closed whilst rail and air travel were hit by cancellations and delays with emergency services running. Motorway hard shoulders were no longer being gritted as priority for the salt was given to the worst-affected regions. Milk deliveries were disrupted too as the tankers struggled to reach dairy farms with farmers. The 12th saw more snow overnight for many in the south, along with the upland SW too, with 5-10cm quite widely. Temperatures across England and Wales were just -1.9°C, a full -6.1 degrees below average, possibly one of the coldest starts to January ever recorded . By the 15th though the very cold spell was over as much milder weather started to return to many areas and a slow thaw began. Given the amount of snow in many upland areas it took a considerable time to thaw though. On the 16th a balmy 12.3C was recorded at Chivenor (Devon), the warmest temperature this month.

By the 26th after a milder, somewhat uneventful spell for a week or so, somewhat colder weather returned as an arctic northerly blast developed giving further snow in places mainly exposed east and west coasts. The month ended on a cold note as well. Minimum temperatures fell to -8C in the south at Hurn (Dorset) (and Benson, Oxon) on the 30th/31st and -13.3C on the grass at Hurn. The period around the 26th-28th saw unusually coloured sunsets in places also. Atmospheric expert Les Cowley believed the bright pink and dusty orange colours seen could be a type of Polar Stratospheric Cloud (PSC) lit by dust in the upper atmosphere.

Soil temperatures were below average generally esp around East Anglia & the SE & fell markedly by the middle of the month, esp in central, northern England & much of northern, eastern and central Scotland- to well below average with frozen ground common here but rose generally after then to generally somewhat below average. Sea temperatures remained near or rather above average around most parts though but were below average around the western & SW approaches, east Anglia and Irish Sea by the month's end.

Forecast summary for February 2010

The first week of February sees a cold north or northerly westerly flow move away initially as weak high pressure ridges over the UK, giving a mainly chilly period at first for most parts but it seems a more S’ly flow will develop across the west by midweek, bringing milder air into the west and SW though keeping the east dry and somewhat colder in the main, with the risk of a few wintry showers and generally some night time frosts and freezing fog. By the weekend low pressure systems in control again for most, giving some milder, wet and windy weather for many, though always a bit drier in the east with some hazy sunshine at times at least initially with hill snow across Scotland later. By week two continuing mainly unsettled & rather cloudy though the east drier with sunny periods and some freezing mist and fog patches by night at times too with some showers, sometimes wintry in the north more especially. Maybe drier in the east later too with high pressure more dominant for a few days at least giving some colder nights centrally & away from coasts in the east. By week three staying rather unsettled with low pressure close to southern areas and the north east & east generally rather drier but still seeing some rain & showers at times, these wintry in places with snow at times for upland areas especially in any short lived NE'ly spells, as depressions sink & decay SE into the continent with colder weather here at times as a result. By week four, the month ends rather unsettled still with further low pressure areas running SW & overall sunshine in short supply; the south west and Wales probably seeing most in the way of rain or sleet & hill snow with the risk of some significant precipitation in these parts but more settled elsewhere, though there may be some wintry showers at times and some frost and freezing fog by night inland.

Temperatures during the month overall staying near average, with some mild days and nights especially in the west, though below average at times in the east initially and again later in the month. Near or slightly below above average frosts generally, more especially below average in western areas; eastern parts nearer average. Rainfall near average for most northern and western parts but some eastern & SE areas may be a below average & sunshine near average overall for most parts though the NW may be slightly below.

Sea temperatures a degree below average for most coasts especially around the SW and Irish Sea; soil temperatures rising to become near average for most parts, but maybe slightly below in the east still with soil moisture near average in the east & remaining slightly above average for most other areas, especially in Wales and the SW of England and possibly NW England and S Scotland too. Snowfall generally near or below average for most parts though highland Scotland may see quite a lot at times.

Week 1 1st -7th February

Initially a cold N-NW’ly flow in the east will move away as a weak ridge of high pressure moves up across the west later on. Moderate frosts and localised mist patches at first across many inland areas of Scotland, Wales and England, but further west and NW mainly to cloudy with some wintry showers about. The weak ridge of high pressure moving across to the eastern & central UK by Tuesday though an area of rain sleet or snow associated with a front may try to push NE in the west and central areas giving local accumulations over hills for a time. By midweek any high pressure moving away to the east as the S’ly flow increases across western parts. The west becoming milder & cloudy and the east too after any rain & sleet clears away. After midweek it looks as though the S-SW’ly flow will continue for most with low pressure areas pushing into the west. Some gales or severe gales likely through the SW approaches and Irish Sea & up into W Scotland and N Ireland. However slight frosts are still possible in the north east & east with a lot of low cloud, mist & fog patches about too night and day. By the weekend, it seems that further areas of low pressure will push up from the south west allowing the wet and windy weather to continue in the west; some of the rain heavy at times and followed by blustery showers with some hail and in Scotland hill snow. The east a bit drier and brighter but rain bands will move east and NE here too at times in a strong S- SW’ly wind, becoming more NW’ly later.

Generally becoming less cold as the week progresses, though the east may start below average by day and the SW will be milder initially as well. Rainfall below average in the east initially but then near or above average later on for most parts especially in the west. Sunshine remaining near or rather below average everywhere overall.

Week 2 8th-14th February
By week two continuing mainly unsettled for many as low pressure areas push up west of Ireland with fronts crossing the UK. Less unsettled with some sunny periods and some freezing mist and fog patches by night in central and eastern areas in any temporary ridges or cols but overall a lot of cloud about for most with limited sunshine. Some wintry showers may affecting the north at times especially over higher ground. By the end of the week as high pressure develops to the east again and perhaps ridges west over the UK, it may become a bit brighter by day with some colder nights too with some frost though the west more likely staying rather cloudy with rain or showers though.

Temperatures generally above average in the west and in the east too initially, though nearer average in the east later, helped by chillier nights. Sunshine slightly below average for most parts, though perhaps nearer average in the east later with rainfall about average for most parts of the SW, west and NW & central areas but slightly below in eastern & NE’ern areas.

Week 3 15th-21st February looks like staying rather unsettled with low pressure to the south or SW in the main though pushing up and lying across southern or central parts for a time in the period. Some strong winds in the south west and south at times. The east & NE always drier but still generally unsettled with low pressure never far away, in a mainly SE'ly flow. Rain or hill sleet or snow at times for most of England and Wales, mainly localised hill snow in central and southern parts. With high pressure developing to the NE again the lows developing to the west or SW may sink SE into the near continent , allowing for some mainly short lived NE'ly flows for northern & eastern parts especially, strong at times , with rather colder weather here at times as a result.

Temperatures generally near average in this period across most parts but maybe a little below average in the east & NE. Rainfall near average in most parts but perhaps a bit below average across the north with sunshine near or rather below average in the south and SW, though the north and NE may be a little above average.

Week 4/5 22nd-28th February
Whilst there are no clear signals about the end of February as yet, it will however probably see an unsettled start as further low pressure areas run across or close to the SW and southernmost UK. The west & NW may see some active fronts too though whilst the east sees the best of the drier sunnier slots but overall sunshine in short supply; confidence is low on rain amounts but the south west and Wales probably seeing most in the way of rain or sleet & hill snow as low pressure and associated fronts slide east across these parts with the risk of some significant precipitation in these parts. Always more settled in the east though a few wintry showers around coasts at times and some frost and freezing fog by night inland.

Temperatures staying near or a little below average for most parts, though maybe near average or mild locally in the west & SW at times, rainfall near average for the west, south west and south, below average in the NE. Sunshine generally near average on the whole though slightly above average in the north and NE.

Dave Wiseman
UKww Executive/C & M Manager/Warnings team