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Mr Freeze

What Are The Perfect Weather Conditions For Snow & Cold Weather?

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As a complete numpty when it comes to predicting weather conditions. Could you please tell me what makes the perfect weather conditions for snow and cold weather. Also could I ask anyone if they know what would be the perfect scenario for snow for me on the far North North West of Cumbria right on the coast of the Irish Sea. Thank You!

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Not sure about the first part of the question, but i will try with the second half. Cumbria is has hills all around it so it can be very hard for snow to make it across the hills, however over the last couple of years we have had great snowfall from an Easterly. Although i think the North-Westerly flow is MENT to be better for us as the Irish sea comes into play. There is also battle ground cold v mild as the atlantic tries to move, however they have been crap this year.

Im sure someone can explain better than me soon lol.

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Frontal Snowfall from the W (like today's and yesterday's) can give very heavy stuff when it passes, but is usually a bit too mild for coastal areas, unless of course, it's cold enough (haha).

From convective snowfall, a NW/WNW flow, bringing showers from the Atlantic, and then pepping up in the Irish Sea.

For coldness, an ENE or E flow from the continent is probably coldest in Winter, as the showers probably won't reach to the far NW coast, and with a frigid airmass, sustained cold and clearness is likely for you.

In Summer, for you and everyone, then a direct N flow from the Arctic brings the coldest temperatures.

Hope this helps :)

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Best conditions for heavy snow on the west cumbrian coast are caused due to either one of the two scenarios explained below:

1 - frontal snow from the atlantic bumping into cold air, you really want the front to align itself on a NW-SE trajectory rather than S/N or even less favourable a SW/NE trajectory. A NW-SE trajectory ensures the flow remains onshore and helps prevents any milder undercutting and often when this occurs the front will stall in situ and pivot eventually either fizzling in situ as it begins to edge east or even better being forced to move south again due to stronger heights either to the north or east. A classic example of such a synoptical pattern establishing itself wason the 5/6 Feb 1996. That event brought nearly 2 feet of snow to the coast. They are rare events but when they come off they are the best for heavy snow on the coast.

2- less likely to deliver long lasting heavy snowfalls, but best for delivering short sharp heavy falls, is a very cold unstable NW/WNW flow tracking down far from the reaches of the arctic. As the flow hits the milder seas of the Irish Sea we get convection and then very heavy snow showers, often thundery in nature. In such flows, troughs can quickly develop and shortwaves giving more organised bouts of snow. A recent example of such an event was the 20/21 Dec 2009, the flow was slightly more west/south west, hence it gave southern coastal parts of Cumbria normally one of the most snow free parts of the country some very heavy snow.

Other synoptics which can deliver heavy snow to the coast, is a cyclonic flow with low pressure anchored to the south or east pulling down very cold uppers from the north. Or a very deep seated unstable easterly, but quite often the lakeland fells squeeze out what is left of any heavy snow showers. Conversely inland parts of Cumbria especially east cumbria can do very well from unstable strong easterly flows, fronts and heavy showers making it easily across the pennines. As recent as early december, much of south east and east cumbria receieved many snow showers off the pennines.

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You can also tell the weather by the clouds as well.

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You can also tell the weather by the clouds as well.

:mellow:

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<SNIP>

I hope this will help you with the bad weather with the clouds.

Thanks, learn something every day me! :)

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Well for charts. Low pressure. Low dew point and temp. Low humidity around 65 to 85% Thickenss - 528 dam line. Well thats about it. Med wind around 10ish mph not too much or the snow will get blown away and wont settle

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I looked quite heavily into this during my Lancaster years and I think Damianslaw is right. Lancaster's biggest snowfalls have traditionally come from frontal battlegrounds with the front aligned roughly NNW-SSE and stalling against cold continental air, e.g. 21-23 January 1984 and 5-7 February 1996.

The "sunshine and snow showers" setups with W and NW winds are often less reliable at the coast because of the exposure to the warming effects of the Irish Sea leading to a good deal of wet snow that fails to settle. However they often provide sizeable falls further inland, and in arctic maritime types with a westerly component to the flow they can deliver even out to the sea front.

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What Are The Perfect Weather Conditions For Snow & Cold Weather?

Temps and dewpoint.

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What Are The Perfect Weather Conditions For Snow & Cold Weather?

Temps and dewpoint.

Temperatures about 0C give the heaviest snowfall.

The lower the dewpoint the smaller the snowflakes... so -1C -2C for the best snow.

Reason being, the colder the air, the drier the air. Basically the snowflakes don't pick up as much moisture on the way down from the cloud, so they can't join together or get larger.

The largest flakes are usually at a dewpoint of around 0C / -1C although this can be marginal.

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So 0.1C gives less heavy snow than 0.0C?

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So 0.1C gives less heavy snow than 0.0C?

Now that's just been silly. :lol:

I meant full degrees, not decimals.

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