Winter 2019/2020 - General Discussion

It's strange that not many long range forecast are going for a cold spring. I suppose one positive of the strong polar vortex, is that if we do get a favourable pattern change, all that cold could come our way.
I think we will see a a change to something much colder sometime in February. In the mean time if we do manage to get a brief northwesterly airflow it could be quite potent given the record cold up in Greenland

nacho libre wrote: »

It's strange that not many long range forecast are going for a cold spring. I suppose one positive of the strong polar vortex, is that if we do get a favourable pattern change, all that cold could come our way.
I think we will see a a change to something much colder sometime in February. In the mean time if we do manage to get a brief northwesterly airflow it could be quite potent given the record cold up in Greenland

My pet theory is that with cold air tending to be 'locked up' away in the Arctic this year, that this will eventually 'unleash' into the mid latitudes during the Spring as the PV eventually breaks down as it traditionally does in that late-winter/early spring period. What effect this would have is another thing. A cold Arctic blast into the the N. Atlantic could well force much warmer air from the tropics over western Europe; or alternatively, an Arctic blast over the eastern N. American continent could power up the Atlantic and bring us much rain. Or maybe, just maybe, this cold air will come down over us and bring us a repeat of April 1917.

Or, as is more likely, I could be just talking bollox.

Carol25 wrote: »

Beautiful two days this weekend, I love the crisp frosty weather. Just a question for those of you saying this winter is incredibly mild. I seem to remember a lot of north westerly’s this winter in November and early December in particular? As regards January-it seems typically cold for this time of year in the West. Probably close to average temperatures? I am open to correction as this isn’t based on data, just my own experience ��.

January has been up to 0.5-1C above average generally to this point (which includes the colder nights that have brought down means somewhat). That temperature anomaly range is very similar to January 2019 which was a mild but not exceptionally so month in of itself. However, I would think that with the coming mild weather that January 2020 will turn out to be milder than January 2019 and it’ll be the mildest January in the country since 2012.

December was similarly milder than average to how this January has been up to now but it was a good deal colder than December 2018 or other recent Decembers like 2015 and 2016.

November was relatively cool and dominated by unsettled northwesterly winds. An absolute atrocious, diabolical, horrifically bad month by any stretch of the imagination. I’d rather erase this month from existence.

How mild winter 2019-20 will be in the end depends on how February goes. Not unprecedented to have two or more exceptionally mild winters in a row though. We only have to go back to 2015-16 and 2016-17 for that which were both well above average for temperatures.

Oneiric 3 wrote: »

Or maybe, just maybe, this cold air will come down over us and bring us a repeat of April 1917.

I had to Google it....

"Strabane, 12 April 1917 - There has not been as cold a spring in Ireland since records began, according to a British meteorologist, Dr Mill.

Ireland is currently in the midst of a brutal spell of April weather. Frost is playing havoc with crops - snowfalls around Dublin are heavy and frequent. Sheep have perished and, in Ulster, a girl living five miles from Strabane was said to have become ‘insane’ after she lost her way in a blizzard and wandered in the fields all night.

Trains have been forced to stop running in various parts after the snowfall was too deep to plough through. There is no likelihood that conditions will ease in the coming days."

https://www.rte.ie/centuryireland/index.php/articles/coldest-irish-april-for-36-years

Sounds great!

Oneiric 3 wrote: »

Current readings, 1048 hPa widely across the south. So the highest January readings in over 20 years, given that highest I could find was 1047.3 hPa back in 2000.

Can anyone say with reasonable certainty what's causing our current high pressure readings?

Say you get a powerful storm here. A strong jet stream and large temperature difference between a cold and warm air mass colliding, could be blamed.

And given that high pressure is the result of cold air descending from high up in our atmosphere and we get these high pressure records in this part of the world in January. Is this the result of a stable polar vortex building up very low temperatures high up in the atmosphere and with the angle of the Sun on the planet this time of year in the northern hemisphere and allowing this cold air to build that it just finds a home in a high pressure system in the nh which atm just happens to be over us atm?
Or is this too simplistic of an explanation?

Thoughts. Reasons?

Naggdefy wrote: »

Can very high pressure cause headache?

I've had awful ones today and yesterday and wouldn't be a sufferer generally.

High blood pressure maybe.

sryanbruen wrote: »

January has been up to 0.5-1C above average generally to this point (which includes the colder nights that have brought down means somewhat). That temperature anomaly range is very similar to January 2019 which was a mild but not exceptionally so month in of itself. However, I would think that with the coming mild weather that January 2020 will turn out to be milder than January 2019 and it’ll be the mildest January in the country since 2012.

December was similarly milder than average to how this January has been up to now but it was a good deal colder than December 2018 or other recent Decembers like 2015 and 2016.

November was relatively cool and dominated by unsettled northwesterly winds. An absolute atrocious, diabolical, horrifically bad month by any stretch of the imagination. I’d rather erase this month from existence.

How mild winter 2019-20 will be in the end depends on how February goes. Not unprecedented to have two or more exceptionally mild winters in a row though. We only have to go back to 2015-16 and 2016-17 for that which were both well above average for temperatures.

Thanks you for the info Syran! Interesting info here to ponder.

Frost that was forming last night in cork city is gone now. Mild and a bit cloudy

As we move into the last third of January, the wintry window is now starting to close. Chance of a real deep freeze in 2020 is looking slim to me unfortunately. The models have been very bleak for weather watchers since the start of December.

While we may get a cold snap in March, I have no grá for that type of weather. There is nothing like a proper deep freeze in the real core of winter, which for me is late December through to around Valentine's Day. Think 1987, and 2010. I did not enjoy the Storm Emma near as much, which seemed odd and unnatural given the time of year, messy and unwanted.

The only thing I would note is that the GFS ensemble diagram is showing a 60% snow probability for Dublin on January 28th. As this is likely from a northwesterly I would not pay it much heed. Mountains will be white most likely