Sunday, 22 March 2015

Weather guide Monday 23rd to Sunday 29th March 2015

Headline: Rather cool with frosty nights; some rain or showers at times

Last weeks highlights

Showery rain more persistent than anticipated in last week's guide over much of the South and West Midlands during Monday with many places receiving 3 or 4mm, with a Solihull PWS recording 11mm. Few showers affecting West Wales (WW) nor the NE Midlands however on Monday. Tuesday still an isolated shower in places but overall it was a dry week, the majority of rain gauges collecting less than 5mm and with next to nothing across much of WW, a mere 0.2mm in total for the past 7 days at Mumbles, Swansea for example.  Many nights were frosty last week, both Tuesday and Wednesday nights down to -4.6c here at Llanwnnen, the former colder than any official UK Met station, with nearby Trawsgoed at -3.7c and -3.5c respectively. Then on Thursday night Swyddfynnon, Ceredigion the coldest spot in the UK at -3.2c, with Saturday night (last night) the coldest of the week across WW,  -5.0c at Llanwnnen.

Thick fog greeted last Wednesday which did though turn out nice with sunny spells. A beautiful sunny mild Thursday across WW and eventually the Marches contrasting with supressed temperatures, murk, and polluted air over most of the Midlands, 12.8c the high at Milford Haven, Pembrokeshire on Thursday contrasting with 6.2c at Little Rissington in the Cotswolds. Friday was mild with sunny spells with 15.5c (60f) at Pershore the warmest place in the UK, but cooler and cloudier for Cardigan Bay and NW Wales, max just 8.3c Aberporth. Saturday another of those days when much of the the Midlands was  plagued by North Sea cloud keeping it quite cool while Wales and the Marches were sunny and relatively mild.

The week ahead

We are in a rather cool airmass for much of the coming week, and although there will be some showers and longer spells of rain some days will be mostly dry and bright, Wednesday looks one such day. As ever some places miss out on the showers in any event and end up having a mostly dry week. After a sharp Spring frost Sunday morning is again sunny over WW but more cloudy over the Midlands, during this afternoon we should see some sunny breaks for the Midlands while WW gets more in the way of cloud, highs Sunday 9c where overcast and 13c where brightest with light winds. Clear spells and a slight frost tonight, this lifting after midnight at least over Wales where it clouds over. The weakening cold front slowly sinks SE during Monday, a largely cloudy and cool day for WW with mainly light rain on and off, it stays dry with sunny intervals for the Midlands before patchy rain arrives later in the day. Max temperatures Monday 8 or 9c WW and 11 or 12c Midlands, it may brighten for WW just before dusk.

Clear spells and a touch of frost on Monday night, once any cloud and rain has cleared the Midlands that is, lows around zero. Meanwhile showers will be affecting parts of WW later in the night, these with hail and becoming wintry over high ground. Tuesday and we are in a rather cold NW flow, sunny intervals but also a fair crop of showers, some heavy downpours with hail and perhaps thunder, even a little sleet or snow possible for highest ground. As ever though a few places could miss all the showers and have a rather pleasant albeit chilly, dry day with sunny spells! Maxima Tuesday rather cold at 7 to 9c, with a cool and quite fresh NW breeze. Most of the showers die out on Tuesday night to leave clear periods and a frost, -3c locally.

A weak ridge of high pressure gives a mostly dry but cool Wednesday, although still a few showers scattered about most places should be dry with sunny spells. Rather cool again though at max 8 to 10c. Clear spells and frost forming during Wednesday evening getting down to below zero across the Midlands, but cloud and rain arrives for WW after midnight, although timings of this rain front are uncertain. This front is proving not straightforward for the models, it may hold together and give quite a wet day, particularly for Wales, or it may fizzle out so that after some early rain it becomes mostly dry afternoon. Another rather cool day maxima between 8 and 11c depending on varying degrees of dampness/ brightness. We should be seeing another ridge and attendant frost for Thursday night.

Mixed signals, as is often the case by the end of the week, most models bringing in an Atlantic low with rain and strong winds during Friday, while with some we scrape a dry day, temperatures though no better than the average of 10 to 12c. Next weekend too looking unsettled with some rain at times, and by Sunday it may well be milder but windy as well as rather wet!

No comments:

Post a Comment