Why has there not been much snow in this decade for Ireland compared to the last one?

nigel_wilson wrote:

The only real snow we experienced was during Nov to Dec 2010. I remember how everything stopped then. We haven't had anything snow afaik for 7 years. What's the meteorological explanation for this?

The previous time we had snow like that was 1982. I wouldn't be expecting another anytime soon

Snow is the most difficult thing to forecast in our country as everything has to be just right for it to take place with thunderstorms not being far behind in terms of difficulty of forecasting, even in the shortest term possible. First we have to look at how does snow occur? What even is it? The average person knows it as frozen rain. Here's the UK Met Office definition of Snow:

Snow is a type of solid precipitation which occur in a variety of minute ice crystals at temperatures well below 0c but as larger snowflakes at temperatures near 0c. It is formed when temperatures are low and there is moisture trapped in the air or atmosphere above us. Tiny ice crystals in clouds stick together to become snowflakes. If enough crystals stick together, they'll become heavy to fall to the ground. Snowflakes that descend through wet air that is slightly warmer than 0c, will melt around the edges and stick together to produce big flakes. Snowflakes that fall through cold, dry air produce powdery snow that does not stick together.

Our location around the world has a large say in why snow is difficult for us to record and get. We are in the mid-latitude yes but we're also surrounded with bodies of ocean/sea water that is milder than the land temperatures in Winter and cooler than the land temperatures in Summer. This situation can lead to rain around the coasts but snow a few miles inland.

Secondly, the higher you are the more likely it is to snow due to temperature dropping with height. Like it may snow at a time on a mountain when everywhere else it rained. The Scottish mountains for example had their snowiest Winter for years in 2013/14.

We often run into battleground situations where two contrasting air masses meet each other. Snow is possible at the line between the two air masses and perhaps blizzards (as it is the boundary between both air masses) but it vitally depends on which air mass wins the battle or which is more stubborn. Like a 1035hPa block is most likely to win the battle against a 990hPa low for example.

Another factor is if the location is an urban or countryside area. Urban areas are less likely to get snow due to the warming effects of the surroundings and pollution.

Last but not least on what can influence the recording of snow, if it rains continuously at a fairly high temperature like let's say 4-7c, it can cause the air temperature to drop and as a result, turn the rain to snow. This is due to heat being absorbed by the evaporation of water vapour from the raindrops as they fall.

There are lots of possible reasons why snow has been far less frequently this decade although the 90s and 00s were far from perfect as well. I'd like to first state though that there was snow during early December 2011, Winter 2012/13 in early December in northern regions, during mid-January in scattered places, during February (early and late) and much of March. There was also snow in parts on 11 February 2014 as the winds turned into a northwesterly briefly after a front passed through overnight. Early February 2015 might have had some snow in parts but I'm not sure whilst early March 2015 brought some snow flurries. 2-4 March 2016 too brought some snow.

Firstly, solar activity comes into play. Solar minimum took place in 2009. The best chance for cold winters according to research is just after solar minimum. Winters that took place just after solar minimum/around solar minimum include 2010/11, 2009/10, 1996/97, 1995/96, 1986/87, 1985/86, 1976/77, 1975/76, 1964/65, 1963/64 and 1962/63.

Here are the IMTs for each of these Winters with their anomalies - bar 1964/65 and 1963/64 'cause I have not calculated them yet:

2010/11 - 3.1 (-2.4c below the average)
2009/10 - 2.6 (-2.9c below the average)
1996/97 - 5.6 (+0.1c above the average) (February was exceptionally mild whilst January was near average with a very cold start and December was quite cold with -1.2c below the average)
1995/96 - 5.1 (-0.4c below the average (December was very cold, February was quite cold and snowy but also stormy. January was very mild)
1986/87 - 5.2 (-0.3c below the average)
1985/86 - 3.6 (-1.9c below the average)
1976/77 - 4.2 (-1.3c below the average)
1975/76 - 6.1 (+0.6c above the average)
1962/63 - 0.2 (-5.3c below the average)

All information here is calculated by me from Met Éireann and UKMO's historical data

As you can see from this data going back to Solar Cycle 19 (we're currently in #24), there was only one mild Winter near or at solar minimum - though I don't have the data from the other two Winters but going off of my memory, 1964/65 was cold with 1963/64 being close to average on the cooler side. Solar Cycle 24 has been the weakest Solar Cycle since #16 which was from 1923-1933. That was a poor period for cold Winters - a knock on effect for us now? Predictions show that scientists think Solar Cycle 25 will be even weaker and will eventually descend us into a new mini Ice Age. I won't go too much into that as it's a controversial topic and let's say, I'm not an expert on it.

We should reach solar minimum by 2019/20 meaning that we are getting very close to be having our best chance of cold Winters.

I'm sorry that I don't have time to continue it on from here, maybe another day I will.

Danno wrote: »

14th January 2015 3cm+

I forgot about Storm Rachel’s snow oops and yeah wasn’t sure if lowlands recorded snow in March 2017.

Ye snowstorm, it was early February 2012. Ireland got so damn unlucky. It was a very mild February at an IMT of 7.2c which comes to +1.9c above the average.

beefburrito wrote: »

You're definitely right about the Easterly winds.
In fishing and Surfing we call them offshore winds.
These offshore breeze's and winds flattens the Atlantic....and combined the Easterly winds and south Westerly swells bring in beautiful surfable waves.
I remember back from 2011 back there was always periods of offshore winds and glassy ocean conditions.

A lot of you here are well up in the scientific explanation of the weather.

Hopefully we'll get plenty of Easterly winds this winter and it'll be much drier.

And some snow thrown in for good measure.

"Much drier"

Was last Winter not enough for ya? :P