Winter Weather

[David Nicholson]

Thanks. It is an odd weather pattern, and an unwelcome one. Beginning to snow here now, and the news says that local trains will not run tonight as a precaution. It only takes one snowflake for things to grind to a halt!

It takes only half a snowflake here! I'll be very surprised if we get any snow here apart from on Dartmoor we have only had one measureable quantity in the 30 odd years we have been here.

[Robert]

The weather here, too, is a bit odd, mainly that it is so late in the season. It was 23 F, -5 C, at the farm Sunday morning, another record for the date. This record was a bit extreme for the date. This morning it is raining in Sacramento. The first measurable precipitation for February. This is extremely unusual! The westerlies are still cut-off and the stormy weather is coming from the north. Not much moisture in this northerly flow, but it is better than nothing. The next storm on Wednesday will be in a much more westerly flow and much wetter. Currently we are at about 58% average precipitation to date. We need rain! and snow in the Sierra Nevada.

[Harald-Alex.]

- 15 C here last night. And not at the ground level. Some further cooling foreseen. The inflow will slowly change from NE to E-  this means cold here. Siberia gets closer.

.                 Hallo Jacek, I hope, the Siberian temperatures are over soon, we had now four nights under -10 grades C and sunny, but frosty day ! I am in Scotland to visit Castle Cambo and wish after comeback to Germany better weather! It is unbelivibl, how many energy the little snowdrops have, to stand up every day ,when the temperatures are over zero! Greetings Harald Alex

[ian mcdonald]

In the winter of 1946/47 ( a very cold and snowy winter) there were heavy snowfalls late into the winter. I remember my Mum telling me that snow was still on the ground at Easter. That year Easter Sunday was on April 6th. I was not found in my pram until the snow had gone. There,s nothing new under the sun.

[ian mcdonald]

This was the last time we had plenty of snow here. 1-12-2010.

[johnralphcarpenter]

Snowing hard here right now.

[Jacek]

Last night -12 C and day max -10 C. The reason for lack of significant drop in night temp was the presence of thin layer of clouds that prevented radiation.

Robert gave us the link to 500 mb map - but being lay person in meteorology it is difficult to understand to me. I understand, it reflects the situation at the half of earth's atmosphere (by weight and pressure) - this is about 5500 m asl. This is certainly important, but we live in the bottom layer of 10-20 meters and our small plants - in the last 10 cm. The layer of coldest air may by quite thin and very local, created during long winter night. This is especially true in the lowlands and far from any warm sea, where nights are calm and mixing effect of wind disappears.

For me more interesting (and unknown) is why the engine of warm northern Atlantic has stopped. And - is there relation between advection of cold in Europe and in California.

According to the excellent Norwegian long term forecast this cold period should be finished at the end of this week. The Mediterranean engine is already switched on and I suppose it will spread slowly to our area. Probably no risk of truly severe frosts, but last night absolute minimum temp in Poland was -26 C, close to Lithuanian border. Weather is seemingly stable, but each night is different.

[Jacek]

Last night temp min -18 C. The reason is obvious - it is the clear sky.

[GordonT]

It is mild and snowless here in Nova Scotia. My concern is that plants may start growing, only to get hammered by a return of freezing temperatures. Maple syrup producers in the province have already tapped their trees, perhaps the earliest start of the season in history. At 9:00 AM today the temperature outside is +4 C. The sky was clear last night, and remains so today. Our two ponds are ice-free. I suspect Viburnum x bodnantense 'Dawn' will be the first to be in bloom.

[Robert]

For me more interesting (and unknown) is why the engine of warm northern Atlantic has stopped. And - is there relation between advection of cold in Europe and in California.

Jacek,

Understanding the basics of 500 mb air circulation and the Jetstream will not only help you understand why local surface weather conditions are the way they are, but are essential for understanding how weather condition on one part of the globe may be influenced by conditions elsewhere. Having some basic understand of fluid dynamics (the atmosphere behaves much like a liquid), and the influence of ocean temperatures/circulation on the atmosphere will be helpful too. It does not hurt to know something about aerosols, solar radiation, Kelvin waves, etc. The ENSO and MJO certainly influence global weather patterns. Climatologists are still grappling with their understanding of these phenomenon and other aspects of global weather. It is a fascinating subject. I am certainly not a climatologist, however I have a keen interest in knowing what you find out on this subject.

[Robert]

Yesterday we had a huge thunderstorm with 5 mm hail. The hail was small, however it persisted for a long time. The temperature dropped from 53 F to 39 F in less than 0.5 hours.

I did get some photographs from the garden before the storm, which I will share ASAP.

Now I have to go to work. 

[ian mcdonald]

We keep getting flurries of snow here then the sun comes out. Nothing settling yet.

[angie]

Same here Ian but they say it will be worse tomorrow for us in the North East. Just hibernating here with a  stock of chocolate 

Angie 

[ian mcdonald]

Good idea Angie. It,s addictive though.

[Maggi Young]

Aberdeen Rock Garden Club - group of SRGC - tonight's meeting has been cancelled because of the bad weather. Please tell any other members you know who the group may not have been able to contact.

 Which is why Angie, Roma  ( our Speaker) - and I will all be cosy at our homes this evening and not trying to travel in the snow.