Well here we are nearly at the middle of January already, Tempus fugit indeed !
Over the course of last week we saw yet another southerly-orientated low pressure pull in some pretty hefty rainfall totals over Ireland, Wales, England and Scotland topping up an already high water table and saturated soils. Walking yesterday it was evident that any dry-down at the start of January had been negated by the heavy rain at the back end of last week. To me this seems the wettest winter we have endured and indeed it has been quite different from other wet autumn / winter in terms of the pattern of weather. Firstly, it started very early (third week of September), secondly there have been very few dry-down days since then and lastly, the low pressure systems have been southerly-orientated and slow-moving, leading to heavy daily rainfall totals. You will I think be pleased to hear that the high pressure signal mentioned last week for the end of this week is still looking odds on, so a dry respite is on the way. How long it ends up lasting is anyone’s guess 🙂
Some form of colder weather must be on its way though because all of my late-brood Hedgehogs have simultaneously hibernated (the parents did so back in the third week of November). This wasn’t before I managed to get one visitor to my garden (Parky) to the local wildlife hospital because at 235 gms he wouldn’t have been able to survive till spring. Stella is in there as well as she needs treatment for lungworm and a damaged leg. Hopefully both will survive and will be fit & healthy come March for me to re-house in my garden. Chatting to the staff there I learnt a lot more about Hedgehogs including how to get them to uncurl 🙂
So let’s see if this week’s forecast turns up some nicer weather for us all and if the Hedgepiglets were right ?
General Weather Situation
So Monday starts off as predicted last week with very strong winds and rain, some of it heavy. In the image above you can see the low pressure off the west coast of Ireland and the tightly-packed isobars that will bring us an unsettled start to the week. So from early doors on Monday we see rain, some of it heavy pushing into Ireland and also some scattered showers moving across England and Wales from The South West. Through the course of the day that rain will cross Ireland and make landfall across the west by lunchtime. It will then take most of the afternoon to reach central parts and overnight will cross all of the U.K. The accompanying winds will be very strong with gale force gusts likely. With a south west wind it will also be very mild across the south with temperatures expected to hit double figures. So wet and windy for the west, dull, drier and quieter for central regions till the wind and rain arrive.
Tuesday sees that rain clearing away into The North Sea and a dry start for all areas, but not for long. Some showers will kick off from dawn for westerly coasts but during the late morning, a new southerly-orientated low pressure system will push into the south west of Ireland and England bringing further rain from lunchtime as it tracks north easterly. Ireland will also see that rain across the south and west move north eastwards through the morning and not to be outdone, Scotland will pick up rain across the north west. Some of that northern moisture will fall as wintry showers across elevation. That rain for Wales, England and central / western Scotland is in for the day but Ireland should see it clear away as dusk approaches. A real north-south divide temperature-wise with Scotland in the mid-single figures whereas down south we look to push well into the low teens. Very windy again from the south west.
Wednesday sees that rain still placed in a band across East Anglia and The South East, otherwise you’ll start dry save for some showers along the western-facing coasts of Ireland and the north west of Scotland. Through the morning that rain across the south east will depart but we will still see some showers for The South West, Wales, The North West and north-west Scotland where again they’ll be wintry. Through the afternoon that mix of rain, sleet and snow across Scotland will push eastwards into central areas. Windy still from the west / south-west and cooler as well with more in the way of sunshine away from western coasts on Wednesday limiting temperatures to high single figures. A good drying day though for most areas.
Thursday sees yet another southerly-based low push into the south and west of Ireland from the off. Now with tightly-packed southerly isobars this low will track more north than north east so during Thursday morning it’ll cover Ireland and push into the west of Scotland. Some of the rain associated with it will be heavy across Ireland. England and Wales will start off dry, particularly across the east and central areas. Around lunchtime that rain will push into The South West and South Wales and through the course of the afternoon, push eastwards into central areas clearing Ireland as it does so. So where you start dry, you’ll end up wet and vice-versa for Thursday. Again very windy from the south / south west with the strongest winds across Ireland and the west of the U.K. Temperatures will range from 8-10°C.
Finishing off what has been an unsettled week, Friday sees a day of sunshine and showers with most of the showers early doors across the west and north of England and the west coast of Ireland, Wales and England. As we move through the day those showers become less widespread and the wind drops down announcing the arrival of high pressure from the south west. So a drier 2nd half of the day for many, still with some showers across central areas and western coasts with some of them wintry across north-west Scotland. Cooler for Friday despite a westerly wind with temperatures down to 6-8°C.
So how do we look for the weekend ?
Well with high pressure pushing in we should see a dry weekend for everyone, colder as well with the risk of night frosts, just what we need to break up the soil and dry areas down. Winds will be light and from the north west reflecting the colder feel to the weather.
Above is the GFS projection for next Monday, 20th of January and as you can see we have high pressure in situ. I can’t remember the last time I wrote that in this blog but it is good news. How long will it last ? Well maybe a week, maybe a tad longer for the south but through next week we look to have a cold, settled and dry spell with night frosts. This will gradually break down from the north towards the end of next week with some windier and more unsettled weather for Scotland towards the end of next week.
Want to know when it is going to get colder ?
Simple, Ask a Hedgepiglet…..
OK, we will start off this week’s notes with a look back at December 2019 and also 2019 as a year….
GDD – UK Location – Thame, Oxfordshire
So December 2019 went out as a pretty cool one with a total GDD of 31, ranking it very similar to 2018 and previous years. As confidently predicted , 2019 wasn’t going to set the GDD world alight from a yearly total perspective, coming in below 2000 total GDD for the year and a good way off the peak years of 2017 and 2018.
As I’ve commented on before, I don’t believe the U.K & Ireland’s climate is following the climate trend we hear about so often on the news in terms of rising temperature year-on-year. This is because of our island location and the fact that the jet stream dictates our weather. Now of course there’s an argument to say the peak and trough patterns forming in the jet stream are the result of climate change with theories pointing towards less temperature differential between the equator and The North Pole. This means less energy driving the jet stream at certain points of the year and therefore more potential for the formation of Rossby Waves. (peak and trough patterns)
Certainly our weather nowadays seems to come in set ‘blocks’, the 10-week summer of 2018, when we had continuously high E.T, air temperature and no rain. The 12-week (and counting) block of autumn / winter 2019, with near continuous rain and very few drying days.
GDD & Rainfall – U.K Locations – December 2019
Looking across the GDD, my Netatmo data comes in lowest GDD for the month again, by virtue of my shaded back garden location I think rather than my unwillingness to put the central heating on 🙂 The biggest variability for December across the locations is not in growth but in rainfall with Fife coming in as one of driest and the warmest from a GDD perspective. This is because Scotland picked up some milder air at the end of the year and for many days was significantly warmer than down south. Wettest again was down in The South West with 219mm of rain falling in December, that is over 4 times the driest location and shows that the predominant rainfall patterns were south and west-orientated rather than the traditional north and west. You have my heartfelt sympathy lads and lasses down that neck of the woods….
GDD & Rainfall – Irish Locations – December 2019
Ireland follows a similar pattern but here there is much greater variability between locations Killiney coming in as the coolest location (16.1) by way of its higher elevation. Only a few miles up the coast as the Seagull flies and we have Donabate at 51.7. Just shows you can’t presume from a general location how your growth pattern has / will been / be. Valentia stands head and shoulders above the rest as the mildest and wettest, but you can also see the southerly and westerly orientation of the rainfall with Cork, Claremorris and Valentia, the wettest Irish locations.
I thought it might be a good idea to look at the total rainfall for 2019 for the sites that submit their weather data to me (thanks as always one and all) and also look at how much of that rain fell from September to the end of December. The results are pretty interesting……
Total rainfall for 2019 and autumn contribution – U.K Locations (all readings in mm)
It’s amazing to see the consistency in terms of the % of the yearly total rainfall that fell in effectively a 13-week period from the 3rd week of September to year end. For the U.K locations that we monitored, between 47 – 58% of the total rainfall of 2019 fell in effectively the last 25% of the year. So you want to know why everywhere is so wet ? well there’s your reason…. You can download the above graph here
Total rainfall for 2019 and autumn contribution – Irish Locations (all readings in mm)
For the Irish locations, the % of yearly total is lower on the whole varying from 35 – 53%, with the average down in the low 40’s. Nevertheless it is still reflective of a wetter-than-usual autumn / winter period….. You can download the above graph here
Another significant feature of autumn / winter 2019 was / is the lack of dry-down days that gave the soil a chance to return to some form of healthy oxygen status rather than the low oxygen / saturated soil status it has been for weeks now. I’ll do some digging into this particular feature later this month but time is marching on…
Microdochium nivale activity update
Last week I mentioned the activity peak between Christmas and New Year and this was repeated again last week as we picked up some very mild, southerly air and high humidity.
On most sites it seems to have shown as new activity around the edge of an existing fungal patch rather than new activity across the sward from a greens perspective. The type of activity shown below would be typical on a Poa annua-dominated green. Thanks……ah ah
Speaking of our old friend Poa annua, it has been a pretty good autumn / winter for this grass plant species although it hasn’t had the temperature to grow as much as we would normally see in a wet winter because as my GDD stats show we have been wet but not mild. With low light and high rainfall I would also expect to see moss species on the up as well with the balance tipping towards them and away from grass.
Let us hope that as last year we transition into spring quickly and growth picks up well allowing the balance to swing back in favour of grass growth.
Rarely does a Meteoturf module tell a better story of this week with mild day and night temperatures accompanied by rainfall through the week resulting in a nice bit of growth and then a sharp drop-off in both as colder high pressure arrives. This one is for the Bracknell area of the U.K. As we progress through this week I expect low Microdochium nivale activity because of the strong wind and rain and for this trend to continue through next week as the colder air arrives.
I hope to catch up with many of you at Harrogate next week but at the same time try to avoid my half-marathon training regime going down the pan at too fast a rate 🙂
A delicate balance if ever there was one 🙂
You can find the Headland Weathercheck link for Harrogate here…I reckon it’ll be fine, dry and cold.
OK, that’s me for another week…
All the best.