Penellype's Weather Channel

[Jay22]

More or less the same here Burnie, frosty with a bright full moon sky although no snow last night. This morning high winds and rain, not sure of temperature yet though.

[burnie]

More or less the same here Burnie, frosty with a bright full moon sky although no snow last night. This morning high winds and rain, not sure of temperature yet though.

What area are you in Jay, north, south, east or west?

[Jay22]

West Burnie, right on the Firth of Clyde for my sins

[burnie]

West Burnie, right on the Firth of Clyde for my sins

Ahh the tropical side then lol.

[Jay22]

Yes, continually wet and windy!

[Penellype]

After a very cold and raw day today with some snow on hills, we are due for quite an abrupt change. There should be some milder and possibly quite sunny weather over the next week or so, giving the illusion that spring has arrived.

It will be very tempting to rush out and sow/plant loads of stuff, but remember it is still February. The light levels are still low and the days are still short. There is a significant possibility that after a mild spell which could last upto a couple of weeks (but don't bet on it), the weather could turn colder again. March can be a very cold and sometimes snowy month and it is too far away to say with certainty that it won't be. The effects of the stratospheric warming are still uncertain - a similar (but slightly stronger) event in 2013 led to an abnormally cold spring.

Now, am I going to be able to take my own advice and resist the temptation? I wouldn't be betting on that, either...

[KevinM67]

^^^^^ regarding light levels,

This is a handy wee site, which gives you an indication of the no. of hours/daylight each day for your area.

You just need to enter your location in the box.

Daylight calculator (number of daylight hours, with sunrise and sunset, and daylight saving time) in Ghent, Belgium (or anywhere else)

[Penellype]

Just a quick update to show where we are at present, and what is expected to happen.

Currently we are under a ridge of high pressure with the wind coming from the south west, and it is likely to get warmer through the weekend. By mid day on Sunday we have this:



The upper air temperatures are warm and the air is coming from the azores, so temperatures will be well into double figures, with 16 or 17C possible in places, especially if the sun comes out. There will be a fair amount of cloud and pinning this down under high pressure is always difficult.

By Wednesday things are starting to look a little different:



The high is sinking south and low pressure has moved into Scotland bringing wet and very windy weather if this chart is correct. Note that on the western side of the low the air is coming from a very different direction - I would expect the mountains of Scotland to be seeing snow by this point. England, Ireland and Wales are still warm as the air there is still coming from the south west.

The low then moves east and a weak ridge of high pressure forms but by midnight on Friday another low brings more wind and snow to Scotland and probably high ground in northern England:



This low is further south and the whole country now has air coming from the north or north west. This would be cold, with night frosts.

The current runs of both the GFS and ECMWF have the south westerly winds returning within a day or so, but a glance at the ensemble shows that this is far from certain and some of the runs are quite cold:



So, enjoy the current mild weather, be prepared for wind, rain/snow and possible frosts later next week especially in the northern half of the country and don't assume that winter has quite finished with us yet.

[Penellype]

Warnings have been issued for wind, rain and snow as storm Doris brings an abrupt end to the spring-like conditions on Thursday. Severe weather warnings - Met Office

The first area of low pressure will move north of the UK tomorrow, bringing heavy rain to the west and strong winds to northern Scotland:



The real trouble can be seen brewing to the south of Greenland, just into the orange colours, where there is a marked Z shape in the isobars. This is the developing storm, which is caught up in the jet stream and heading straight for us. Move on 24hrs and you have this:



The strongest winds are to the south and west of the centre of the low, which is moving east across the middle of the country. There is an amber warning of strong winds through north Wales and the midlands and a much wider yellow warning area. As the low moves east it will drag air in from the north and there is a yellow warning of snow for parts of Scotland and the pennines.

This is a small and mobile low pressure system so it won't last long and should have cleared the country by Thursday evening. However there has been mention of the possibility of a sting jet forming, which could bring hurricane force gusts for a short time.

The message is clear - batten down the hatches, tie down or bring indoors anything that might blow about, and be prepared for possible disruption to travel and power and possible damage to buildings if you live in the path of this thing. Good luck!

[Penellype]

After Thursday's storm there will be a short cold snap on Friday, followed by more wet and windy weather over the weekend, although not as windy as storm Doris. Beyond that there is considerable uncertainty as shown by this morning's very messy ensemble chart:



The situation is complicated, and I can't do better than Matt Hugo's explanation and forecast in his excellent synoptic guidance released earlier today: Synoptic Guidance - Storm Doris and Beyond - Blog by Matt Hugo - Netweather.tv

[Penellype]

Storm? What storm?



The "eye" of storm Doris passes over York at mid-day with gorgeous blue skies, bright sunshine and light winds. Lurking in the distance is the cloud associated with the "2nd wind" - the western flank of the storm. This hits suddenly and hard, and has stronger winds than the earlier eastern side. We look to be going to be relatively lucky here as the storm is moving to the east south east, with the very strongest winds on the southerly and south westerly flank passing just to the south of York. It was warm first thing, but is already starting to feel colder as the wind swings round to the north.

[Penellype]

About time for an update.

The currently mild period is coming to an end after today, with temperatures slipping back to nearer normal for February, possibly slightly cooler. Expect night frosts if skies clear, and some snow on higher ground, particularly but not exclusively in the north. With low pressure the dominant feature this week it will be wet at times and sometimes windy, especially in the west. The actual weather pattern is complex and pinning down exactly where and when it will rain is quite tricky.

This is Monday's midday chart:



The low pressure over us is rotating around but not really going anywhere, with various fronts and troughs associated with it moving generally from west to east at times. This will continue during the first half of the week before a weak ridge of high pressure gives a better day on Thursday:



Then it is back to square 1 on Friday:



This sets us up for a wet day on Friday with further areas of rain or showers likely over the weekend. Note the weak area of high pressure over and to the east of Greenland - it is this which is keeping the low pressure over us rather than moving on the more normal track to the south of Iceland.

Friday's chart shows a deep area of low pressure over Newfoundland (purple) which on this run of the GFS model stays roughly where it is and fuels a ridge of high pressure over us (warm air advection) for the following week. This is beyond the reliable timeframe, and I'd be inclined to wait and see.

The ensemble for York looks like this:



The drop in temperature into tomorrow shows very clearly, with the upper air temperature dipping to around the -5 mark, nearly cold enough for snow. The rainfall associated with the low pressure systems shows marked differences between the members as early as tonight, pinpointing how hard it is to get the timing of this right. Western areas will be wetter than this. As always uncertainty increases with time so that by 3rd March there are noticeable differences between the runs, and there are massive uncertainties by 7th.

So, expect a cooler, often wet and at times windy week.

[Muddy_Boots]

....... or here is the alternative weather forecast according to Ian McCaskill ....

[Penellype]

So, now that winter is officially finished, how did the forecasts go?

Well, November was colder than average as predicted, and we did have some short cold snaps interspersed with milder intervals, which was just about what I predicted. The high pressure had several attempts at becoming established over Scandinavia during the winter, without actually managing to make us really cold (it was a different story for southern and eastern Europe though, where they got the full force of the arctic blast for quite an extended period of time).

December was mild and dry. This is a most unusual combination for winter and would have been very difficult to predict. January was around average and quite dry, colder in the south than in the north. February was very mild and slightly wetter than average in places. The net result was a warm and dry winter with an average temperature about 2 degrees above normal and about 75% of the expected winter rainfall. Obviously there are regional variations, but given the overall mild and dry outcome, I don't think my "forecast" was particularly good! However, it wasn't as bad as the papers as we didn't see the heaviest snowfall in years, or the "wall of snow" that was shouted about in the headlines.

[Thelma Sanders]

we didn't see the heaviest snowfall in years, or the "wall of snow" that was shouted about in the headlines.

If they say it often enough - perhaps one day they will be right! You'd think they would know better by now