With March all but gone and April just round the corner you’d like to think that we should start to see some warmer temperatures and more spring-like conditions. As mentioned numerous times so far this year though our friend the jet stream is providing a road block to this type of progress by maintaining its trough pattern.
There are some (weak) signs that this may change in the coming weeks but what needs to happen is for heat to build in southern Europe and effectively push the jet stream higher in latitude. It is this absence of heat that’s the issue and until we see a good, strong heat signature in the Atlantic, we are likely to stay in this cooler weather pattern, though we have some milder weather in store for later in the week and the weekend hopefully…
Countryfile and their early spring…???
I watched Countryfile at the weekend and I was amazed at the way they kept going on about how early a spring it was because this flower was out in so and so and this tree was in bud in this place. All the references were from February and that’s true, we were way ahead of the game back then, but now ?
If you look at the GDD data in the agronomic notes section, you’ll see this March has been one of the coolest we’ve endured for a long time so any early gains have long since been negated in my mind by this and for sure a cool start to April. My Snakes Head Fritilaries (image right) are later than last year and only just coming into flower whereas this picture was taken on the 2nd April, 2012 and then they were in full flower. All this keeps my mind ticking over about our favourite flowering plant, Poa annua and when it is likely to make an entrance in this topsy-turvy year in terms of seedheads.
General Weather Situation
So how are we looking this week ?
Well after Storm Kate threw her toys out of the pram and blasted her way through the U.K yesterday with heavy rain and strong winds, Tuesday looks a much calmer picture with a dry, bright start for most people. The exception is where we have some heavy showers and these are currently working along the west coast of Ireland, South Wales and Northern England. These showers could well be a mixture of snow, sleet, hail and / or rain with accompanying thunder. As we go through the morning these showers will push north east across the U.K into south east England, north east England and the south west of Scotland. Pushed along by a blustery, cool south west wind. Ireland looks to have a mainly dry, bright afternoon after those wintry showers push off into The Irish Sea. Definitely a day for keeping your waterproofs close by as there’s an increasing risk of showers over The Midlands and Central England as we go through the afternoon. Temperature-wise, nothing to shout about because although the winds are from the south west, they originate from up north and so keep temperatures pegged back to high single figures.
Overnight into Wednesday, the showers slowly fade to leave isolated wintry ones affecting the north east of England and Central Scotland. With clear bright conditions for many, temperature’s will drop to close to freezing for the start of Wednesday so a ground frost could be likely. Wednesday morning sees those wintry showers still in situ over The Highlands of Scotland and also some morning rain is possible for south east Munster, along the Leinster Coast and across Donegal. Aside from The Highlands, it looks like Wednesday will be bright and sunny across most of the U.K with a hazy cloud cover. Any showers look to dissipate by the afternoon to leave a clear fine end to the day for most areas. Temperatures may just nudge double figures on Wednesday but with a clear night beckoning, they will tumble down to close to freezing.
Thursday is the change day of the week because after the hiatus following Storm Kate, a new low pressure is heading our way from The Atlantic (though this one looks to skim over us) and that means a change in wind direction and temperature. So a fine, dry, cold start for many on Thursday. Ireland will see cloud build pretty much from the off and this heralds the arrival of a rain front pushing into the west coast by early afternoon. This rain will move eastwards across Ireland but since it’s pushed along by a mild, south westerly wind it is likely to head diagonally into south west Scotland for late afternoon rather than affect England or Wales. Elsewhere we’ll see another dry, bright day with cloud cover building across the west, but even though the wind will be light, we will struggle to hit double figures across Wales and England. Into Thursday night and that mix of rain and wintry showers (for elevated locations) continues to affect Ireland and Scotland, whereas south of this it remains dry.
For Friday we see that rain sink south overnight into north west England and Wales but it doesn’t look at this stage like it’ll get any further south than a line drawn from Newport (Wales) to The Humber. So Friday morning sees that band of rain still in situ over Ireland and Scotland and slowing sinking southwards. Away from this rain it’ll feel milder in a moderate south westerly air stream. By lunchtime the rain should have cleared all of Ireland save for a reluctant band sitting over Wexford (sort of way) and moved north and east across northern England, Wales and southern Scotland. For central and southern England it’ll be a mixture of sunshine and clouds for the end of the week, but staying dry and feeling milder.
‘Mixed’ is the word for the weekend I think with that band of rain still coming into play but it will feel much milder. Overnight into Saturday that band of rain moves back north and west as the wind swings round to the south and so the east of Ireland, north west of England and Scotland could well see rain on Saturday morning / afternoon. A drier start elsewhere but by late morning a band of rain looks to push into southern England and then move northwards through the afternoon. By close of day Saturday that rain should have largely cleared Ireland, Scotland and most of England save for the north east where it’ll end the day. Temperature-wise I think we should see early to even mid-teens on Saturday with a light to moderate southerly wind. The exception is across the west I’m afraid and that means Ireland where it’ll feel cooler and they’ll be more in the way of cloud cover because of that rain so not a great weekend here I am afraid. Sunday looks less unsettled with a lower risk of rain showers and a nice, mild spring day though the wind looks to shift more westerly / north westerly, but it’ll be light in strength. Ireland should have a sunnier day, but still feeling a little cool I’m afraid.
So does April hold the key to the start of spring ?
Well certainly the beginning of next week will feel like spring has arrived because we’ll see a continuation of that mild theme for most places and dry to boot for many areas. The exception may be across Ireland on Monday and south west Scotland, but for the rest it’ll feel nice and mild on Monday with light winds in place. The same for Tuesday, maybe a tad cooler but still dry and sunny for most areas with the highest threat of cloud across the north and west. Wednesday should continue that theme, milder across the west now but I’m afraid it’s all change on Thursday as a new, cooler low is projected to swing down. That means a change in wind strength and direction to south westerly / westerly and a risk of rain across Scotland accompanied by a drop in temperatures. By Friday that rain will have sunk southwards to give a cool and unsettled end to next week. So not out of the woods yet in terms of temperature I’m afraid
I’m going to carry on the theme from the last few weeks and look at how we’re doing as we progress through to the end of March…So here’s a look at 2016 GDD vs. 2015 to the end of March….
You can see that my prediction for nearly identical GDD at the end of March 2016 vs. 2015 is just about bang on, so I hereby claim the smug prize for GDD prediction (no other candidates obviously) and promptly retire on the winnings to my luxury Swiss-style villa overlooking Shiskine Beach on the Isle of Arran
Now I know this is only one location and I’m going to be really interested to see your GDD spreadsheets for the end of March so please email them in to me and I can have a good look and show the difference between different regions of the U.K and Ireland. I’ve already had a glimpse of a 2016 vs. 2015 comparison from Co Cavan (Cheers Peter) and there they are ahead and staying ahead so I think we will see significant variation between westerly locations like Ireland, Wales and the south west of England vs. central locations. Time will tell.
The reason why I take issue with Countrywide is clear to see when you look at how the three months this year have shaped up GDD-wise…
So how does that compare ?
So what we can see is we had more growth in January and February and precious little in March until the last few days. March 2016’s projected total GDD of 16.5 for this location is the 2nd lowest we’ve measured for this location, the lowest being the cold winter / spring of 2013 when we hit 12.5 for the month, so clearly spring 2016 is nothing to shout about !
To put it in perspective growth-wise, a good growth month for March would return around 60 GDD in total for the month so we’ve only had 20% of the growth level of a mild March this year.
If you’re seeing slow recovery from aeration carried out in March or your winter season pitch to cricket conversion is a little lacking, this is the reason why.
The plus side is that you should have seen some growth over the last few days and are destined for more once the milder air stream comes in at the end of the week. I expect for most areas you’ll see the first good greens growth over next weekend with a rise in clipping yield by next Monday morning.
Plenty of purpling going on….
Now I know there’s been some purpling around for a little while now but looking at last year I posted about purpling on March 9th, a good bit earlier than this year for sure.
I’ve created a pdf extract which you can download here but one point that’s worth re-iterating is that this purpling only occurs on the top surface of the leaf because it’s the area on the grass plant that’s exposed to direct sunlight. If you flip the plant leaf over, the underside will be green and that’s why it isn’t a disease or a nutrient deficiency.
Poa annua Seedheads
So where does this leave us with respect to predicting when Poa is likely to seed in earnest ?
Note – I’m talking the Perennial Poa seedhead flush on fine turf here…
That is a very good question and in my mind there are two scenarios ;
- An early seedhead flush because Poa annua grew significantly during December 2015 and is therefore in an advanced state of seedhead development
- The Poa seedhead flush will be similar to other years based on a GDD total of around 130 (U.K biotype and different from the Irish Poa biotype). So currently we’re sitting on 70 ish for our Thame location (I appreciate other areas will be lower and higher) and April can serve us up anything from 60 – 130 GDD, which means we could see Poa annua seeding in the third week of April if the month is warm and the end of April / early May if it is a cool April.
The question is which scenario is right ?
Danish Sea Scurvy, that opportunist, halophytic (salt-tolerant) plant that’s been exploiting the salted areas of our motorways and other road systems is starting to come into flower already and that is early for sure, so if Poa follows this example we’ll see seeding pretty soon. You can read about it in an old BBC article here.
My money is on scenario 2, that of a more traditional Poa seeding date because I don’t think we’ll see the heat required to really push Poa seeding into top gear anytime soon. Time will tell I’m I am right, but I’d appreciate your experiences on this front if you’d care to drop me an email or a comment to this blog.
Ok have a good, short week..
All the best..