Penellype's Weather Channel

[Penellype]

Yellow warning of fog in the east midlands this morning - typical of high pressure. This should soon burn off (as will any cloud in most parts of the country) in the increasingly strong spring sunshine.

The models are having 2nd thoughts about bringing low pressure and rain in after the weekend, and this could be confined to the far north and west of the UK. The high pressure is looking increasingly inclined to rebuild - as always its exact position will determine the temperatures, but (away from the northern half of Scotland) expect warm and sunny conditions, becoming quite hot over the weekend, at least until Monday, with dry conditions possibly continuing especially in the east, for much of next week too, although as always this could change.

I could do with some rain as my soil is already getting really quite dry, especially in the raised beds.

[Penellype]

Quite a lot of uncertainty creeping into the models now. The warm and dry weather looks likely to hang on until Monday, after which it gradually becomes more unsettled from the west. It will also become cooler, but not particularly cold as far as I can tell. There are big disagreements about what happens next, with the shorter range models tending to keep low pressure in control into May, while the longer term ones seem to insist that May will be dominated by high pressure.

May is a difficult month to forecast anyway, with the winter temperature contrast between the pole and the tropics fading away, resulting in generally less active weather which is tricky to predict.

[Penellype]

Enjoy the last day or 2 of fine and warm weather - it is going to get colder and wetter as the week progresses. Rain and possible thunderstorms will spread north tomorrow into Wednesday as a low pressure makes the air increasingly unstable. The low then gets stuck over us for the rest of the week with associated rain or showers. Models disagree on how this pans out, but the temperature will certainly drop, and some have the wind turning into the north, which would be cold enough for night frosts towards the end of the month and into May. The current GFS operational run (thick green line below) is one of the coldest and has night time temperatures below freezing for many places throughout the first week of May. Wintery showers would also be possible in the north .



While this is one of the coldest it is not the only one and it is not unusual to have a cold snap with frost towards the end of April. Keep an eye on the local forecasts as despite current appearances it is not summer yet.

[Nicos]

Thanks Pen!
I need to prioritise the direct sowing in that case before I get rained off!

[1Bee]

Brrr. Distinctly chill wind today, and I'm holding off putting the tender plants into the growhouse as I'm not convinced it will stay above 10C...

[Gillykat]

Getting quite foggy up here in Alnwick at 8pm....could see it rolling in from the coast which is 4 miles away when I left the allotment at 6pm. Definite chill in the air but a refreshing chill after the crazy heat of the weekend.....if that makes sense?

[Penellype]

Interesting split developing between the various ensemble runs and models for the early part of May. The colder, wetter interlude now looks short, lasting until Saturday, after which it looks likely to become warmer and drier as high pressure builds back in:



Into the first week of May there are 2 distinct sets of lines, one lot cold and one warm, with very little in between. As always this is all about what happens to the high pressure. The colder runs have the high retrogressing (moving from east to west) to end up over Greenland. This turns the wind into the north or north east, which is cold. The warmer runs keep the high over and to the east of us, bringing the air up from the south or south east. This is much warmer, hence the split.

It will be interesting to see which (if either) is right.

[Penellype]

I should probably have added to the above that a rapidly developing low pressure system is due to arrive in the south west tomorrow night and has been named storm Hannah. There is a yellow warning of wind in the south west and south Wales https://www.metoffice.gov.uk/weather...ate=2019-04-26. Expect gales if you live in the affected area and strong winds in the southern half of the country - make sure that garden furniture etc is secure.

[Gillykat]

Hannah can stay away from Northumberland!!!!! Her mate Gareth trashed my shed roof so lord knows what Hannah would do.....probably finish it off

[chillithyme]

It was definitely a much cooler and windier day here, sudden change from the warm bank holiday weekend, I won't be making the mistake of working outside without a jumper tomorrow, as I did today

[Penellype]

Hannah can stay away from Northumberland!!!!! Her mate Gareth trashed my shed roof so lord knows what Hannah would do.....probably finish it off

Hannah will mostly affect the southern half of the country - it may be quite breezy further north but not gale force winds.

[Penellype]

Storm Hannah update - Met Eireann (Irish Met Office) have issued a red warning of wind gusts around 90mph for County Clare. The remainder of south west Ireland has an amber warning, with most of the rest of Eire having a yellow warning.

Stay safe if you live in SW Ireland.

The Met Office have issued a yellow warning of rain for the whole of Northern Ireland.

[Penellype]

Suddenly the ensemble runs make up their minds about what happens over the bank holiday:



Only one of the very cold runs (blue) remains, everything else has gone with the warmer option. While the next couple of nights might be chilly, the prospect of a series of potentially damaging frosts following next weekend looks to be diminishing. This isn't a certainty, but its a lot more reassuring than having half the runs hovering somewhere below -5.

[Penellype]

...or not. This is just ridiculous! This morning's operational run (thick green line) joins several others that have flipped back to cold over the bank holiday weekend:



This would bring night frosts in places as high pressure takes over within a cold airmass brought down by a northerly wind on the Friday.

The ECMWF is also showing the colder option this morning .

[Nicos]

Yikes!...frost again?
I suppose that would mean sunnier days though?