160125_gfs_pres_500p_loop_eur

Hi All,

The fact that our weather is so critically influenced by the jet stream couldn’t have been more fundamentally demonstrated than over the last 7-10 days. Last week we were in a trough in the jet stream that pulled cold Arctic air down and we hit -5°C and lower, consistently, but by Saturday morning that trough had moved off and was replaced by a peak that pulled warm air up from Africa and we hit a shade under 15°C here yesterday.

I was out cutting my front lawn yesterday to slightly bemused looks from passers-by, but as I explained to one of my neighbours, “Grass doesn’t grow by the calendar”, so if the air is 15°C and the soil is 11.5°C, it’s growing whatever month of the year it is…

TB205

This blog is 5 years old today, actually it was last week and I looked back at my first posting on Jan 17th, 2011, before starting this one. 5 years ago almost to the week I was commenting on air temperatures of 13.5°C and a soil temperature that had risen rapidly into double figures due to mild rain falling, sounds familiar doesn’t it ?

Thanks to everyone who popped by at BTME to say hello, sorry to those who did so and I was busy yapping, my apologies. I took a lot of stick about that sheep though….:)

Onto the weather and have my hopes of a stabilising high pressure for some of the U.K and Ireland for this week been answered ? in a word, no. The high is sitting below us, but there’s a huge cold low over Iceland and so we are caught between the two. Where a high and low meet it funnels the wind between the two pressure systems and that’s what we’ve got coming in the week ahead. After seeing the huge snow storms over the east coast of America, we know that these frontal systems will push over The Atlantic, pick up milder, wetter air and then dump their moisture over the U.K and Ireland, so that’s what we have to look forward to I’m afraid.

General Weather Situation

So we start this week with a westerly / south westerly air flow and that means, mild, wet and windy conditions will prevail, however we will pick up some cooler air along the way as well.

Starting off on Monday morning we have rain already into Ireland and south west Scotland, but sitting here at my desk watching the sun rise, the sky was beautiful and now it’s clear. That rain, light in nature, will push into more areas through the course of this morning, so by lunchtime I’d expect it to be over Wales, the south west and north west of England and Central Scotland, falling as a mix of wintry showers over the latter. As is often the way, south and east of this rain front, it’ll be mild, calm and dry so a nice start to the week really. By close of play Monday most of that rain will have fizzled out across the U.K and Ireland so a dry end to the day for most areas. Mild with temperatures in the low teens, but as the sky clears after the rain / cloud cover it’ll feel noticeably cooler, especially under clear skies. The wind will be blustery through the day and from the south west.

For Tuesday we see a much heavier band of rain ploughing the same furrow overnight pushing into West Ireland and onto Scotland by the morning rush hour. This rain will be heavy in nature and likely to cause localised flooding in western areas unfortunately. By mid-morning it’ll be affecting most of the west coast of the U.K down to South Wales and Ireland as well with some particularly heavy bursts across south west Scotland, north west England and Wales. South and east of these areas you’re unlikely to see this rain until later in the day. So by dusk it’ll be into south west England and Northern England and the worst rain will have cleared Ireland. Rounding off Tuesday night that rain pushes across all of the U.K, but it’ll be much lighter by the time it reaches south east and eastern areas. A cooler day with temperatures in the high single figures but it’ll actually get milder as we go into Tuesday night. The winds will be moderate to blustery and from the west / south west.

For Wednesday we see a re-run of Tuesday with heavy rain pushing into Ireland early doors. This rain front will however move more quickly from western areas to central and eastern areas so everybody will see significant rain on Wednesday although as usual the worst of the rain will be across Ireland, western coasts, Wales and the south-west of Scotland. With colder temperatures over Scotland, that rain will turn to sleet and snow with significant amounts expected over higher elevations, but I expect lower levels to see some as well. Scotland is really getting hammered this week I’m afraid by rain, every day sees significant rainfall and that’ll mean flooding I’m afraid for a lot of areas. By the end of Wednesday that rain will largely have moved away from the U.K and Ireland to leave a clear night though there may still be some wintry showers over Scotland and North Wales and some vestiges of rain over the south east of England going into Thursday. Temperatures will be milder on Wednesday, into low double figures but again that wind will be blustery and from the south west.

Thursday presents a much drier brighter picture but there is rain lurking out west and time will tell how much of the U.K and Ireland it really affects. Where skies are clear there is a likelihood of a light frost for most areas and in general it will feel much cooler. Cloud cover will build through the morning over Ireland, but any rain initially should only be over Donegal and north west Connacht. So dry and bright, but feeling much cooler for all areas as the low pressure picks up some colder air. NorthSouthdivide

By late afternoon that rain gathers strength and pushes into Ireland and then follows that familiar path of affecting the west and north primarily, whilst the south and east miss the bulk of it. (see map left) Overnight that rain sinks south and affects all areas but lightens as it does so. So temperatures much lower for Thursday, in the mid to high single figures and still with that westerly wind though perhaps lighter through Thursday.

Closing out the week and it will seem for the west and north like more of the same I’m afraid because we see rain over north west Scotland and Ireland, Wales and the south west of England. There may also be some light showers over The Midlands and central areas as well. Through Friday morning that Scottish rain pushes into central and south west Scotland and then later northern England. All the time though the worst affected areas are western coasts. Wales will also see a continuation of what has already been a very wet week I’m afraid so not much joy to send your way at the moment. Into Friday night and that rain sinks south into England, lightening as it does so. The winds will really ramp up for the end of the week so strong westerlies, Gales in places and that’ll peg back temperatures to high single figures, all in all a crap end to the week 🙁

So as you’d expect the outlook for the weekend is unsettled with strong westerly winds and a good chunk of rain. For Saturday that rain will have a southern orientation so although all areas of the U.K and Ireland will see rain through the day, the heaviest will be across South Wales, the south west of England, Central England and The Midlands up to the M62 sort of area. It’ll take most of the day to clear and later I expect some of that rain to turn to wintry showers again over Central Scotland. These will linger on into Saturday evening. Ireland will have a wet start to the weekend, but the worst of the rain should clear through by lunchtime so some patchy sunshine as well. It’ll remain on the cool side and the winds will be very strong and from the west. Sunday looks to be a re-run of Saturday so rain pushing across Ireland from the west and quickly into the western and then central areas through Sunday morning. Again the worst of the rain will be a.m. Winds will be westerly and it’ll remain windy.

Weather Outlook

Next week looks to start off with more of the same I’m afraid as that deep low slowly moves eastwards, so initially wet and windy for Monday, however as that low moves off, high pressure is set to build again from the south and west. As it does so the winds will swing round to the north so a good bit cooler later on Monday, early Tuesday I think and then hopefully some dry, cold and settled weather for all of us from mid-week, next week. I don’t expect it to last that long though as more heavy low pressure systems are stacking up behind it, so a return to milder, unsettled, windy and wet conditions is on the cards for the end of the week.

Agronomic Notes

NorthSouthdivide

When you have a geographical map split like this you can kind of guess the advice, suggestions, comments and feedback are going to be pretty split as well 🙂

Prior to this week most areas have had a 4-5 day cold and largely dry spell (save for the snow) and for me it was amazing how areas had dried up locally whilst out walking yesterday. Of course for Ireland, the west and north, this picture was spoilt by a dump of rain at the end of last week. For other areas though it re-affirmed to me the reason why turf was so wet after Christmas, even though the total amounts of rainfall hadn’t been out of the ordinary. (for the south and east)

For sure it was the lack of drying days that has characterised the pattern of rainfall this winter and that started in November.

Looking at the stats for the month so far we can see the lack of drying days very clearly, even at a dry site like The Oxfordshire with only 5 days (out of 24) completely dry. Now I know other areas will have received a lot more rain than this site, but I bet the number of drying days is similar and so is the effect, a wet surface canopy.

RainfallGPTheOxJan2016

On the growth side of things we can see that levels have been quite normal really for January with little or no growth since the mid-part of the month. This has changed over the weekend with a sharp increase in temperature and so I expect an increase in clippings to be greeting you this morning. Looking at the total GDD for the month, we are at 11 on this site and normally January checks out somewhere between 25 and 40 for the whole month, so it’s been on the cool side this month for most.

Microdochium Activity

This sudden increase in air temperature experienced over the past 2-3 days is likely to have kicked off disease activity, especially where you already have scars present from last autumn and thus a high population is in situ. Aside from areas in the east and south, it’s going to be difficult to treat this from a wind, rain and I’m sure ‘getting to the playing surface’ perspective over the coming week with no spray days for most of you in the worst-affected areas. Sorry I can’t give you better news.

Moss Growth

Low light, high moisture levels and a mild November and December has really ramped up moss growth and if there is an application window open to you, this week is a good time to hit these areas with a high iron product. From a golf course perspective, back tees are an obvious first port of call due to their less play / more organic matter dynamic. You’d have thought that the elevated levels of grass growth at the back end of last year would have out-competed moss but I think the growth dynamic between the two species has been different.

What I mean by that is that I think grass growth has been elongated and upright with little basal tillering as the combination of high air temperature and low light (short days) extended the shoot upwards. The lack of tillering has seen areas thin out even though they are growing with the mild temperatures and this has allowed moss to gain the upper hand.

PGR Usage

This feature of upright growth is precisely the type that Trinexapac-ethyl will control and it therefore lends further weight in my mind to the continued usage of PGR’s (especially on outfield turf) late into the year. Recently I had a GDD / GP spreadsheet sent into me from the south west of England (Cheers Richard) and on this site the end user had been applying a PGR every 200 Growth-Degree Days starting from Jan 1.

Here’s how the frequency of application mapped out last year applying every 200 GDD.

Application 1 – 10th April / Application 2 – 13th May / Application 3 – 10th June /

Application 4 – 29th June / Application 5 – 16th July / Application 6 – 30th July /

Application 7 – 18th August / Application 8 – 7th September / Application 9 – 1st October

That was the final application, but if you’d have carried on applying every 200GDD, the rest of the year would have read…

Application 10 – 2nd November / Application 11 – 20th December

So you can see that initially the PGR applications are monthly, but in the warmer months of June and July they become fortnightly because of the increased temperatures. With a cool August and September they drop back to monthly again but because of the extended growing season through November and December (due to higher air temperatures), the applications could have continued on a monthly basis through November and December.

That for me is the beauty of using GDD as a growth model for applying PGR’s, it changes depending on the actual temperature the grass plant experiences. I know the question you’re asking….Is this PGR application to greens, tees, outfield or what ? I have to apologise here as I forgot to ask 🙁 In my mind this would be greens and tees (and outfield turf if the budget and resources were there). At the very least it vindicates why in autumn 2015, extended PGR usage was warranted.

Bibionid

Warm Soil = Increased Insect Activity = Increased Pecking…

The rain and mild temperatures late last week and over the weekend have kicked into life some insect activity particularly those that are living in the surface. I received a picture today which I’m pretty sure is of Bibionid Grubs (the larvae of Fever and St Mark’s Fly) with a note that pecking had been seen on greens. Bibionids are known to live in surface organic matter and so they’ll be the first type of insect affected by the sudden increase in soil temperature (I’m hoping after those cracking frosts last week that Leatherjackets and Chafers will be deeper down the profile). An additional issue is that I’ve noticed that Corvids started nesting earlier in response to the super-mild temperatures in December and I’ve already seen Crow’s and Rook’s clearly sitting on eggs in their nests. Once these hatch, the young will need feeding and as mentioned in previous blogs, with no Chlorpyrifos option, this will be our first spring when we notice the full effect of insect activity on our surfaces.

So we have a challenging week and season ahead of us for sure…

Five weeks from now though and we’ll be tip-toeing into March, it couldn’t come a moment too soon in my mind…

Rainfall Stats

Last call for your 2015 Rainfall Stats, if you want to send them in, this week is the last week we’ll be taking them, after that the door is shut for another year….Please send them to weather@headlandamenity.com and thanks to everyone who has done so so far….

All the best…

Mark Hunt