160425_gfs_pres_500p_loop_eur

Hi All

Well looking out of the window it certainly doesn’t look like we are only a week away from May as our dismally cool spring carries on, mind you looking at last year’s data, we were still getting ground frosts in the last week of April 2015.

FemaleBlackbird

Talking of looking out of the window or more specifically in through a window, one of the bird inhabitants of my garden, a female Blackbird, has taken to landing on the kitchen window first thing in the morning to give me the evil eye whilst I’m preparing my breakfast smoothy (a complicated 7-way tankmix). Almost to say “it’s alright for you but where’s my food ?”

As intimated last week, this week is going to be a cool / cold and unsettled affair because of a trough formation in the jet stream. Looking ahead I can’t see any respite until the end of the 1st week of May, but there is a glimmer of hope there nonetheless.

General Weather Situation

For many places on Monday we have a dull, damp start with frequent showers blown in on a moderate to occasionally blustery north west wind. Most of these showers are over Ireland, Wales and the south of England, in a line drawn down from The Wash. For most of Scotland and the north of England, you’ll have a brighter morning, but across The Highlands and north east of Scotland we’ll see some wintry showers falling as snow at elevation.  In the afternoon, those showers will dissipate across the west and become confined to the south / south-east of England, though the north east of Scotland will remain wintry. Temperature-wise, nothing to write home about with low double figures in most places but as the sun breaks through in the afternoon it will feel more pleasant. ‘More pleasant’ compared to mid-week especially.

Through Monday night into Tuesday we see skies clear across most of the U.K and Ireland and that could mean a ground frost. Those wintry showers across the north east of Scotland will slip down the east coast into the north east of England overnight and we could also see some wintry showers over The Welsh Mountains and Dartmoor as well. Through the morning that wintry shower mix slips south and inland into Northern England and later The Midlands, falling mainly as rain here. North east Scotland continues to see wintry showers and heavier rain through Tuesday morning as will Donegal. Away from these shower fronts, it’ll be a bright day for Ireland and the south / south west of England, but a cool one nonetheless with temperatures barely able to break double figures as the wind takes on a northerly aspect.

Again with skies clearing through Tuesday night into Wednesday we have a risk of a ground frost across most areas of the U.K and Ireland. As the wind turns round to straight north it’ll pull down colder air and more in the way of wintry showers and longer spells of sleet and snow over Scotland initially but these will soon track south into Northern England and Wales by late morning. Ireland will see the same pattern with wintry showers over the north and Donegal tracking south into Connacht, Leinster and eventually Munster during the morning. By the afternoon this mix of wintry showers and rain will be over most of the U.K and Ireland, but there will be some bright spells of sunshine across Wales, the north east of Scotland and possibly East Anglia as we close out the day. A raw one though with that cold north / north-west wind and highs of 6-8°C likely.

Moving onto Thursday and another raw day is in prospect with a ground frost in areas where the sky cleared overnight. Those wintry showers will still be in evidence though, across north east Scotland, the north east of England and Wales. The pattern for Wednesday is repeated on Thursday for Ireland with wintry showers in Donegal pushing south into Connacht and Munster through the morning. Between these blocks of showers they’ll be plenty of sunshine though so not all doom and gloom. Through the afternoon those northern wintry showers are likely to sink south again into the north east Midlands and along the east coast and here they may be heavy in nature. Again another raw one though with that cold north / north-west wind in situ with highs of 6-8°C likely for most places. As we progress through Thursday evening those showers dissipate somewhat but there’s still a risk of more wintry ones across The Midlands late on Thursday night.

Again with clearing skies for a lot of the U.K and Ireland, we’ll see another ground frost, that’s 4 on the bounce for some areas :(, but with a change in the wind to a more westerly aspect it does mean it’ll feel milder on Friday. After a bright start, that change in the wind direction will push showers across Ireland, the north of England and Scotland later on Friday morning and some of these showers will again be wintry in nature across mountainous areas. Across Scotland in particular those showers will extend to longer periods of rain and this may mean some significant rainfall totals I’m afraid. South of this rain / sleet band you’ll have a dry, bright start to the day and with lighter winds, temperatures will pick up nicely in the afternoon. At this stage the line between those wintry showers and brighter, warmer weather looks to be drawn north of Birmingham.

So looking forward to The Bank Holiday weekend (for everyone I think ?), Saturday looks a day of two halves with a hazy start to the day for Ireland and the U.K, away from western coasts. Here it’ll be wet with frequent showers from the off across Wales, the north west of England and Scotland, the latter wintry in nature. As we progress through Saturday, those showers, pushed along by a blustery south west wind will move inland across the U.K for the afternoon so take your waterproofs if you’re out and about. Ireland looks to start reasonably dry but by mid-morning we’ll see some heavy rain into Kerry and pushing up country to affect all areas by sun down. Sunday looks another day of sunshine and showers with that rain band pushing in from the west early doors and quickly moving across the U.K during Sunday morning. The second half of Sunday could be bright, but still feeling cool despite a westerly air stream. Monday again looks a day of sunshine and showers and as for Saturday and Sunday, temperatures only just breaking double figures, maybe a tad higher if you catch the sun and are out of the wind.

Weather Outlook

With low pressure still sitting in that trough, next week starts unsettled with plenty of rain on the radar I think. As we progress through an unsettled Monday we enter a battle between an Atlantic high pressure trying to push warmer air in and a continental low pressure trying to resist it. So the isobars get squashed and that means three things ; a northerly wind aspect, it’ll feel cool / cold and they’ll be strong winds as well. By Wednesday things are looking to settle down a bit and most of the rain should have departed to leave a drier picture, but not for long because another Atlantic low is expected to rattle through during Thursday. That will mean that things will begin to feel milder though and here’s where that glimmer of warmer weather to come enters the picture. By the end of next week we are likely to see a southerly air stream in place and if that comes to pass it’ll push up much warmer air from The Mediterranean for the end of next week, next weekend. Lot’s of things crossed and positive vibes on that front for all of us in this industry.

Agronomic Notes

Year-to date Growth-Degree-Day Analysis

Continuing my theme of how the spring this year compares with last, here’s how the GDD stats look up until and including the 24th April…

CumGDDApril24th2016

So you can see (hopefully) that our graph again flattens out this week and in fact falls behind last year. On a daily basis (below) you can see how the warmer air late last week gave us some growth but because we had cold nights (often with ground frost), this growth wasn’t strong in nature.

DailyGDD2016April24th

To give you an idea, an April with good growing conditions, that means milder days and less cold at night, would typically yield between 125 and up to 175 total GDD for the month. So far we’re tracking at less than 60 for most locations and looking at the coming week I think we’ll be lucky to register much if any additions to that total. So if we close out April with a total of 60GDD, it means we had half as much growth as last April and a third of a really good growth month.

Of course there’s a flip side to the picture painted by the GDD data above and that is on outfield turf where this spring has given nice consistent growth without any flushes. That means less cutting, less requirement for PGR’s and less diesel usage I reckon. 🙂

Unfortunately on fine turf we need this growth, in many cases to pull us away from spring aeration work and it has been a long haul if you cored say in mid-March and we are now 5 weeks down the line with only slow recovery.

Poa annua seedheads

Ox240416MTurf

So looking at Poa annua seedheads,  we are just hitting 130 total GDD at a lot of locations, less I know in the north and higher on the south coast, but for the majority I think we are there or thereabouts. It’s at the point where I’d normally expect to see a flush of seedheads, but as you can see from the predicted growth pattern (above) on the Meteoturf module of your Weathercheck, using either GDD or GP, nothing much is likely to happen this week from that perspective.

A total projected GDD of 5 for the next 7 days isn’t worth a jot so I don’t expect much to happen on the seedhead front this week or much of next week actually, but…..

…..If we do get that shift to a southerly airstream later on next week and a rapid pick up in both day and night temperatures, then you are going to see a lot of seedheads pop up very quickly across your fine turf canopy.

Pathogen Activity

Following on from the above, I’d expect to see a very sudden movement on the Microdochium nivale front if we get a rapid increase in temperature however because we should also get a nice hike in growth I’m hopeful that we can grow it out without reaching for keys to the Chemsafe.

Another pathogen that I have noticed out in the field is plant parasitic nematodes, (PPN’s)  especially the endoparasitic ones which have spent the winter safely protected in a root gall or cyst. These have hatched in large numbers during April but it’s unlikely you’ll have seen much in the way of symptoms quite yet.

Plant parasitic nematodes work a bit like Take All as a pathogen in that they do their damage to the grass plants root system in the spring but typically there is little or no expression of symptoms whilst the plant is growing at a slow rate. Once temperatures rise, the plant needs to uptake more nutrients and moisture to maintain growth and replace water lost by E.T and it is then that we see symptoms of PPN damage. Ectoparasitic nematodes, those free-living species that inhabit the soil are usually slower to build population number in the spring but we are already starting to see some symptoms of Spiral Nematode activity on fine turf. So it wouldn’t surprise me to see more in the way of PPN damage by mid-May.

Uptake Windows

If you are looking to apply nutrition this week I’d leave it till the end of the week because the cold, mid-week temperatures will knock back the plant somewhat and this is likely to reduce uptake efficiency, whether it be nutrients, PGR’s or the like. I also think with 4-5 ground frosts within this weeks forecast, it is likely that we will see a loss of colour across turf surfaces this week due to this and a cold windchill, mid-week.

Ok that’s all for now, wrap up well and have a good Bank Holiday..

All the best.

Mark Hunt