160201_gfs_pres_500p_loop_eur

Hi All,

Well that’s January done and dusted and now we move onto what is traditionally the coldest month of the year. As I type this it’s 11°C outside and the soil temperature is a whisker above 10°C, so it’s probably fair to say we’re going into February warmer than ever. Still it’s a short month and then we’re into March, personally I can’t wait.

Jetstream010216

Before we lull ourselves into a false sense of security it does indeed look like February will live up to its reputation for cold snaps as the projections are for us to move from a warm peak to a pronounced deep trough. (see above) That will pull cold air down from Siberia and for sure I think some pretty bracing temperatures and snowfall, particularly as there is a low pressure associated with this trough. So let’s put some detail on it…

General Weather Situation

Monday kicks off with another of those meaninglessly-named storms (‘Enry’ this time) affecting principally the north of the U.K and Ireland although it’ll be windy everywhere. Thankfully there isn’t too much moisture associated with this one, just very strong winds for Scotland in particular. It’s there that will also pick up the rainfall and a mix of wintry showers, principally affecting western coasts. Some of these may drift southwards into north-west and northern England as well and it’s likely that we will see some more showers affecting the south west of England and Wales this morning. Ireland looks to miss most of the rain with maybe North Donegal getting some, but elsewhere (U.K and Ireland) it looks like being a dry day with some sunny intervals. You’ll notice though that it’ll get chillier as we move through the day because that mild peak is passing us by and introducing cold air into the equation. As intimated above that wind will be pretty strong especially over Scotland where I anticipate we will top 100mph across the top of The Highlands, so take care up there on the road and at work. Temperature-wise we look to start in the low double figures but drop as we progress through the day to 7-8°C.

Tuesday follows a similar pattern to Monday  as ‘Enry’ continues to “slap to all over” Scotland (At this point anyone under the age of 35 looks quizzically at the PC and wonders quite what MH is on ?…..For the younger audience there was a famous advert in the 70’s for Brut Aftershave and one of the advocates was the late, great Henry Cooper and that was the catchphrase:)) so a continuation of wintry showers for north and west Scotland with some of these drifting south to affect The Pennines. They’ll be some additional rain over North Connacht and this will drift south through the morning into Munster and Leinster I’ll warrant you. Those northerly wintry showers look to slip south through the afternoon into The Lakes and North Wales by dusk. Again south and east of this we will have a cold, dry but bright day with a chilly westerly wind pegging the temperature down to mid to high single figures.

Onto Wednesday (clever use of bold to accentuate the day of the week you know..) and that mix of wintry showers finally departs Scotland for Northern England and North Wales, so a mucky start to the day here. Elsewhere it’s another dry and bright start to the day possibly with a ground frost in sheltered areas. That band of moisture slips south into the North Midlands by lunchtime but fizzles out after that. Ireland looks to start with a bit of cold rain over North Connacht and Donegal again but this also fizzles out to leave a cold, dry and bright day for most regions. The same is true for England. That cold westerly wind may lighten off a tad but it’ll still feel pretty parky Mrs wherever you happen to be located with temperatures struggling into mid to high single figures, about normal for February.

As we move into Thursday we see a peak of milder, wetter air into Ireland overnight and this will rapidly push into the west coast of Scotland, England and Wales by the early hours. As it moves west though it fizzles out but still there may be some showers inland through the morning. What it does give is a much milder, but duller day with temperatures into double figures again for most areas. That rain never really leaves Ireland so a mix of showers continuing through the day, particularly across the north west and eastern coasts. By close of play, we see more moisture into north west Ireland and this is heavier in nature. The wind will again be brisk to strong and from the west to south west.

So Friday starts off pretty wet for Ireland and Scotland with that rain soon pushing into north west England and Wales. By mid to late-morning the heavy rain is principally affecting the west coast of Scotland, England and Wales and this pushes inland by lunchtime. Ireland will have a bright, cooler interlude before a new rain band pushes in to the west later in the afternoon.By dusk this rain will be into central areas and clearing western coasts thankfully. Much cooler as we progress through the day as that milder rain passes through so mid to high single figures again, even where you see the sun. By Friday night that second band of moisture is falling as a mix of wintry showers across Scotland, the north west of England and Wales, so not a nice end to the week really.

The outlook for the weekend isn’t great I’m afraid (though i said that last week and some places had a nice dry Saturday :)) with that moisture still in situ over Scotland, the west coast of England, Wales and Ireland. It will break up though during the morning to give some sunny intervals so not all bad. Later in the day a strong band of rain and wintry showers pushes into Wales and moves across The Midlands and Central England through Saturday night into Sunday. For once the north of England, Ireland and Scotland is drier. Onto Sunday and that moisture should have exited stage right into The North Sea though it may still linger down across the south east of England. There’s a risk of another low pushing in heavy rain to the south west and south of England during Sunday extending up into The Midlands. Elsewhere a drier and bright day but very much on the cool side as that still strong westerly wind pulls down cold air from the north.

Weather Outlook

So next week starts with us still firmly wedged in that trough I highlighted at the beginning of this blog. With low pressure systems associated with this trough it does mean we will be unsettled with plenty of moisture around but I think they’ll be a difference in who gets the worse. I think that the trend from the weekend will continue i.e that the south of England and Wales will get the worst of any moisture next week, they’ll still be some for the north, but the Lion’s share will be down south. So Monday looks to be unsettled, with sunny intervals and heavy, blustery showers, some of them wintry in nature down to low levels possibly. Tuesday looks to offer a day of respite but not for long as a deep depression is heading towards us and aimed at Ireland and the south of England. So Wednesday sees the wind change direction to the south west pretty much straight away and that milder air pushes heavy rain into Ireland and the south of England through Wednesday. It’ll probably reach northern England, but the worst will be in the south. Thursday sees us back to unsettled and then as that low passes eastwards it’ll drag down northerly winds for the end of the week, so a pretty cold end to next week could be on the cards. I expect next week to see wintry showers through the week, rain mid-week and then back to wintry showers at the end of the week with a cool wind throughout (except on Wednesday).

Agronomic Notes

As we start a new month, we can look back at a topsy-turvy January from a growth perspective courtesy of those peak and trough jet stream patterns.

GDD Spreadsheet

GDDmonthlycomparisonandcumulativeJantoDec2010to2016image

When I watched Countryfile last night, they said this was the mildest January according to the Met Office, but I can’t see how that was actually the case because a monthly GDD total of 28.5 is similar to most other years and nowhere near 2012 at 40.5.

Looking into the growth patterns in more detail using some Growth Potential Stats from Long Ashton and The Oxfordshire, (cheers guys for hitting my in tray this morning) we can see a pronounced period of active growth at the end of month when a warm peak in the jet stream pushed up mild / warm air.

GPJan2016

This peak in growth gave us noticeable clip yield on greens and outfield areas alike and also some recovery on thinner areas / disease scars. It did also push some disease activity into life but much less than you’d expect and mainly on older scarred areas.

This holds with my theory that the main activity period for Microdochium remains October through November and if you are able to keep the population low then, your chance of getting re-infection is much lower (not nil, but lower). Of course this growth didn’t occur at an easy time of the month because in some areas (particularly the north and west) it coincided with high rainfall events as well. This is clearly shown on the daily rainfall stats from the two locations.

RainfallJan20162loc

Interestingly in terms of total rainfall levels, the more central location was wetter than the west, but that said I know across The Bristol Channel, up north and in Scotland, totals were much higher than this for January.

Dry Days and E.T (Evapotranspiration)

In common with November and December, January showed around 2/3 (66%) of the days were wet so the periods when the turf could actually dry down were few and far between.

Interestingly at the end of the month in the Thame location, the total rainfall for the last 10 days of January was 13mm and the total E.T was 10.9mm, so that means 84% of the rainfall was actually evaporated off. This may be one of the reasons that some areas have dried down well lately (not west or north) and possibly why there’s been a lower disease incidence because the leaf is drying more quickly.

Again this high (for January) E.T was down to that warm air pushed up from Africa on a peak in the jet stream. You can see when these peaks in the jet stream passed through by looking at not just the maximum air temperature for the day but the actual change in air temperature across 24 hours. January 2016 was noticeable for some really big swings in daily air temperature. (see below)

AirtTempschangeJan2016

I again appreciate that in the west and north site conditions preclude a lot of the suggestions of last week but I’ll make them again anyway. For south and eastern locations this week presents a good opportunity to aerate and particularly hollow core if you’re in need of snicking in an extra organic matter removal event. The same advice also holds in terms of moss control although with high wind speeds this week, it’s likely that a granular product will be the only one possible to be used.

Bibionid Control Query

Last week I featured an image and some content on Bibionid larvae and I stated that there was no control on the market. Always one to slap my wrists :), Kate Entwistle came back and queried this comment (quite rightly) and sent me a link of the CRD website to a range of products (all with the same A.I – Esfenvalerate) that appear to be labelled for this pest on managed-amenity turf. Whether this approval is still current is tricky to ascertain but if anyone can shed some light on this, please drop me en email or comment to the blog.

Ok that’s all for now…

There may or may not be a blog next week depending on whether I actually make it out to GIS2016 in San Diego.

Mark Hunt