Penellype's Weather Channel

[Penellype]

Update:

There are now signals that the low on Sunday could be rather further south and also deeper. This could lead to several problems on Sunday, with gales or severe gales for parts of the south, heavy rain with possible flooding to the south and east of the low and possible snow to the north and west of it. There is fairly good model agreement even at this stage, so if you have plans for Sunday it is worth keeping an eye on the forecasts for this one.

[Gillykat]

Expect a return to frosts from Thursday night.

Spot on! Lovely hard frost this morning in Northumberland

[Penellype]

Loads of reports of snow on higher ground over night and into this morning. Also some "thunder snow" - ie a thunderstorm with snow rather than rain, which is quite rare.

Some odd weather around yesterday with tornadoes reported in Wales and the Midlands causing significant damage. These were associated with a squall line on a cold front - these are very localised into a sharp band and typically last only a few minutes, accompanied by very heavy rain. The same types of conditions cause these as big thunderstorms - sharp differences in temperature and differences in wind direction with height, causing wind shear which leads to rotation of the air. You can often see thunder clouds rotating with height, and sometimes the formation of a funnel cloud below, which becomes a tornado if it touches the ground.

The models are still not handling Sunday's low pressure particularly well, with a lot of scatter. The Met Office have warnings for ice, wind and rain over the next few days: Severe weather warnings - Met Office

[Lumpy]

Thank you Penellype - I know this sounds terrible but I have never experienced 'thunder snow' and would really like to.

Your forecasting is brilliant.

When will you be able to make a prediction about Christmas?

[Thelma Sanders]

Netweather Christmas forecast here, complete with Santa Shaker lol
Christmas Weather Forecast - White Xmas 2016

[Penellype]

Thank you Penellype - I know this sounds terrible but I have never experienced 'thunder snow' and would really like to.

Your forecasting is brilliant.

When will you be able to make a prediction about Christmas?

Christmas is some way off at the moment. Realistically you would be talking about a good chance of reasonable accuracy from about 20th December. If you can't wait that long, you could try watching these Christmas Weather Forecast 2016 which are well explained but JUST FOR FUN.

[Penellype]

Some exceedingly unpleasant weather tonight and into tomorrow morning in the south with hurricane force gusts possible along the south coast. Charts are from WxCharts.eu - weather chart viewer for Europe and are the high resolution Arpege model, which shows a chart for each hour. This is 6am UTC (equivalent to GMT) tomorrow morning:

Wind speed:



Wind gusts:



A little explanation is necessary as these are not the charts I usually post. Wind strength is shown by the colour, with the scale along the bottom in kph. These numbers look frighteningly large to people used to using mph or knots. The divisions between the colours also look very strange until you realize what they have done. Each colour band refers to a wind force on the Beaufort Scale (see https://en.wikipedia.org/wiki/Beaufort_scale), so blue and green take you up to force 6 (strong breeze, upto 49kph = 31mph), the yellow band is force 7 (near gale, 50-61kph, 32-38mph), red is gale force 8 (62-74kph = 39-46mph), brown is severe gale 9 (75-88kph = 47-54mph), purple is storm force 10 (89-102kph = 55-63mph), pink is violent storm 11 (103-117kph = 64-72mph) the grey area and beyond is force 12 (hurricane, 118kph+ = 73mph+). The table on the Wikipedia page tells you what you can expect to see at each of these speeds for base wind values (1st chart) not gusts.

These charts show damaging gust speeds, so if you live on one of the affected areas, do take care. Secure any loose objects like garden furniture, wheelie bins etc or preferably bring them indoors as these can blow about and smash windows. Close greenhouse/shed/garage doors and windows as these can blow down if the wind gets in and has nowhere to go (my flat roofed brick garage blew down in a gale 12 years ago when the door blew open). If you have to travel, check local news for road closures due to fallen trees etc before you go and be prepared for delays or diversions. Flooding could be an issue too as this lot brings heavy rain with it too.

Good luck, and stay safe.

[Penellype]

Update: tonight's storm has been officially named Angus. An amber warning for strong winds has been issued by the Met Office for parts of the south east Severe weather warnings - Met Office

[Jungle Jane]

Thankyou for the warning,if anyone has anything in blowaway grow tents,they'l probably fly around tonight,good luck that doesn't happen to anyone!!

[Penellype]

After Angus, what next?

This is tonight's chart, showing storm Angus to the south:



Another low pressure system is already forming to the west along a kink in the isobars, and this will run across the country on Monday:



In comparison to Angus this is nowhere near as windy - the isobars are much more widely spaced. There will be a lot of rain on this system with a slow moving weather front producing several hours of heavy or even torrential rain in places.

By Wednesday things have calmed down:



We revert to a cool, cloudy regime as high pressure builds to the north. Northern areas should be dry with some sunshine, but further south there will be a lot of cloud with some drizzle or showers likely. Frosts should be confined to the north where skies clear.

This continues into the weekend:



although things may gradually brightening up a bit from the north as the high pressure moves slowly south. If the cloud does break up, nights are likely to be colder with the risk of frost and fog returning.

The general picture remains uncertain with a lot of scatter on the ensemble chart:



This is for York, further south there will be a much bigger rise in temperature tonight as the low passes over. The 2 lots of heavy rain show up very well along the bottom of the chart, arriving in York tomorrow and on Monday night.

Into December, this particular run shows the operational (thick green line) going very cold, but in the previous run it was one of the warmest, so don't read too much into this at the moment.

[Thelma Sanders]

Yes, here in Kent we have a MetO Amber warning for wind and torrential rain in the morning OMG.

I hope my new greenhouse stays put...

[Penellype]

Fingers crossed for you Thelma.

[Nicos]

We are smack in the middle of the pink area on that gust chart.
And yup.....it's pretty noisy out there!

We've moved our cars away from under the large maple tree they are usually parked beneath....just in case!

[Philthy]

Drove home to Brighton this morning - arrived half hour ago. Very blustery out there tonight for sure. Torrential rain for a time but that seems to have eased up a bit and now the wind is in full control. Some big gusts hitting the building. Quite a few recycling / wheelie bins scattered about, and a warning to stay away from the pier. And the streets are pretty much deserted (but then it is gone 3 in the morning )
Likewise you pretty much have the motorway to yourself when it's like this. Drop your speed to allow for some buffeting and maybe a bit of aquaplaning and the weather isn't a problem.
Think I might watch something scary on telly while listening to the storm rage outside

[Thelma Sanders]

Very noisy out there right now! Wheelie bins flying about and car alarms going off.
I was woken up at 5.30am - it sounded like loose tiles sliding down the roof OMG. (I still remember that from the hurricane that wasn't in '87 )
Have to wait til later to see what's going on - but I'm now downstairs in the safest place, even the cat is hiding Bless!

Stay safe everyone...