March 22nd

Hi All,

Well the spring solstice / vernal equinox has come and gone this past weekend when day and night length were roughly the same. Officially it is the start of spring and the end of winter….hurrah !

A weather week of opposites last week with some parts of England struggling to hit double figures as North Sea Haar dominated the weather picture in the south and east. Head north to Scotland and the closeness of a warm high pressure pushed temperatures there up into the twenties on successive days 🙂

This week coming is a change week as the high pressure that’s been a largely welcome and dominant feature of our weather for the last 7-10 days is due to slowly exit stage right and allow a more Atlantic airflow to come into effect. So that means the west will see those changes first and the south and east, you’ll see it last, hanging onto the high for the first half of the week. This has implications as usual for turf management decisions so I’ll chat about those later in the blog.

The countryside around here though is still pretty wet despite The Midlands being one of the drier areas. Yesterday whilst out walking I noticed running springs at the top of hills and ditches that are normally dry by now, still running strongly. Wildlife is convinced that spring is just around the corner though because Crows and Rooks have young in their nests (which means pecking potential for Leatherjackets and Bibionids is at its highest now), the Hares are still boxing (I saw 5 yesterday) and we happened upon a lovely Dog Fox loping across in front of us. He stopped to have a look once he was at a safe distance, a beautiful animal but one with a love-hate reputation that’s for sure. Sky Larks are on the wing here and I saw flocks of Fieldfares heading east back to their Scandinavian summer and autumn destinations and no doubt hoping to catch a ride on a kind westerly.

March will depart us pretty soon and as predicted, it’ll sign out as a cool one with similarly low GDD / G.P to 2020 I think, so let’s see what the weather is like for the remaining part of the month.

General Weather Situation

So as we start Monday dry with not a speck of rain troubling the Netweather radar anywhere across the U.K & Ireland, save for some showers over Orkney and I’m not sure I have any readers from there so I think I’m safe :). With low pressure trying to push in from the north Atlantic (just out of shot in the GIF above), it is no surprise that the bulk of cloud will be across Ireland and the western half of the U.K, with clearer skies (and a ground frost) for central and eastern areas. And that’s pretty much how we stay set for the day with variable cloud cover, some sunny intervals across eastern / north eastern areas and the chance of some showers across the north west coastal region of Scotland. Winds will be light across England and Wales, but for Ireland and Scotland, you’ll see them increase in intensity through the day, so here they’ll be moderate to strong and from the south west. Similar temperatures to the weekend 10 – 12°C, with a cold start where skies were clearer this morning. (we had a ground frost here) There may be just the odd isolated shower that makes it inland across Scotland and The Borders overnight.

Onto Tuesday and overnight we see a rain front from that Atlantic low pressure trying to push in but high pressure stubbornly obstructs its progress. So again a mainly dry picture for the U.K, with just the chance of showers across The Lakes and North Wales. Across the Irish Sea we will also see showers likely to affect Connacht down to Kerry. That cloud cover over the west is now across most of the U.K & Ireland as the low pressure rain front advances, with maybe only East Anglia seeing some sunshine in the morning. By midday, the rain front will be into the west of Ireland and pushing eastwards though I don’t anticipate it reaching the east coast of Ireland till after dark. Skies will clear behind this rain. The northern end of this rain front will reach north west Scotland by dusk so a wet end to the day there. Temperature-wise, a bit cooler on Tuesday up north where that colder is pushing in, otherwise yep, it’s 10-12°C as per usual.

Wednesday sees the northern part of that rain front fizzle out overnight but the remaining southerly section will be across North and West Wales by dawn. this band of rain will move eastwards into north west England and later north and north eastern England as well as across Wales, The South West and Midlands later. All the time it’ll be diminishing in intensity. More rain showers will pile into the north west coast of Ireland through the course of Wednesday morning with some showers pushing inland. The heaviest rain though will be across the north west of Scotland where some of the showers will be wintry in nature. As those belts of showers push through we will see skies clearing behind them so for the west of the U.K and eastern Ireland, you’ll maybe finish with a sunny end to the day. Those rain and wintry showers across north west Scotland will sink south and east through the course of the afternoon into Central Scotland by dusk. No prizes for guessing the temperature range from the cooler north to the milder south and west, yes, it’s 10-12°C. Winds will be strong to moderate and from the south west.

Onto Thursday and we start the day with a smattering of showers across Ireland and that heavier band of rain still over the north west, west of Scotland and extending down the north west of England towards The Mersey estuary. Through the course of Thursday morning we will see those northern showers pushing inland and some further south across Wales and north west England. If anything these showers will consolidate through the latter half of the morning here and also across The Irish Sea where we will see two bands moving across the western and eastern coasts down through Wexford to Cork. Through the afternoon, those showers will dissipate across the U.K though some could make it inland into northern England and The Midlands. Across The Irish Sea those showers will continue to consolidate to more widespread rain across most of Ireland pushing up into the north as well. The same for Scotland where the rain will continue to affect western, north western and central areas. Temperature wise it’s all beginning to sound like a bit of a scratched record with 10-12°C. Winds will be strong to moderate and swinging round to the north west.

Rounding out the working week on Friday and overnight that consolidated rain front over Ireland will push east into Wales and the west of the U.K, so by dawn it’ll be raining here. Across The Irish Sea, it’ll be a brighter start after the rain clears east with plenty of sunshine. It will be noticeable cooler though as colder air pushes down from Greenland on a north west air stream affecting the U.K & Ireland, so everywhere can expect to have a sharp, cool blast on Friday. That rain, some of it heavy will push eastwards across the U.K with another rain front following close behind into Wales and the west. Scotland will see a mix of rain and wintry showers across elevated areas of the west and north west push east into central and eastern areas through Friday morning, but it’ll clear afterwards. Ireland will also see the same with the east side of the country, brighter and the west, duller with more rain pushing in during Friday morning. Those showers and heavier bursts of rain will funnel through most of Friday afternoon, but we will start to see some gaps in the showers and some sunny intervals developing during the later afternoon. A windier day on Friday and a much cooler one as mentioned above with a cold front dropping south and feeding cold air into a north west air stream. So 7-9°C on Friday with the cooler air across Scotland and strong to gale force accompanying winds meaning the wind chill will be quite marked for the end of March and some of those showers will turn wintry across Ireland, England and Wales.

So with a cool, wet end to the week, how does the coming weekend look ?

Saturday looks mainly dry except for rain across the north west of Scotland. A dull and breezy day with some sunny intervals across the east and some showers arriving late in the day across the west of Ireland. We will still have that strong to moderate north west wind with us on Saturday and cooler air so similar temperatures to Friday I’m afraid. In other words we will be struggling to make it into double figures and below the seasonal average. As we approach dusk on Saturday and heavy band of rain pushes into the west of Ireland / north west of Scotland and quickly moves eastwards. Some of this rain will be particularly heavy across Kerry and Connacht and it’ll fall as wintry showers further north across western Scotland. Overnight this rain will push north and west into North Wales and north western England with some heavy bursts amongst it. It’s a north easterly vectored rain front so that’ll mean South Wales, The South West and Central England down from The Humber Estuary may miss the worst of it. It’ll be a quick mover though so by Sunday morning most of it will have pushed through and it’ll be replaced by a sunshine and showers outlook across Ireland, Wales and England with some rain still remaining for the north of Ireland and north western / Central Scotland. Again the latter may fall as a wintry shower mix. Still breezy on Sunday with a strong to moderate south westerly wind, but temperatures lifting a little for Ireland, Wales and England, back to our metronomic normal of 10-12°C…..yawn…..

Weather Outlook

So as you can see from the start of next week, the high pressure is gone and we have a south westerly air flow positioned across the U.K & Ireland with the milder air across the southern half of the U.K. I’d say classic sunshine and showers weather by the looks of it for the start of the week. As we progress through the first half of the week, a low pressure system develops down across the Bay of Biscay and into western Portugal. The knock on effect of this will be interesting as it should switch the wind into a more southerly orientation bringing better temperatures and also drier weather. As we progress through the week, the winds lessen in intensity and high pressure swings in from the south east ushering warm winds in from the continent. So rain for the north west of Scotland and England on Monday with a band crossing Ireland on Tuesday. The vestiges of this may push into Wales and the west of England through Wednesday next week but all the time the prospect of milder, drier weather looks to loom closer as we approach the Easter weekend. Probably not what the authorities want to hear as another invasion of Bournemouth and The South Coast isn’t what we need for keeping numbers where they need to be. That said I don’t think it’ll be an Easter heatwave as the wind will swing more northerly for the second half of the weekend and that’ll likely mean a bit duller and cooler. Crucially dry though. As usual the normal “It’s a long way ahead” caveat applies and particularly for this forecast as we need to see that low pressure form first to re-direct and block the south westerly air stream.

Agronomic Notes

So a bit of a short one agronomically today because time is as usual in short supply 🙁

Drying out….

I have to admit at the weekend I was surprised with how wet the countryside was after pretty minimal rainfall last week (4.9 mm here) and some dry days but of course we had pretty continual Haar (cloud cover) and drizzle in the second half of the week and that means two things. Firstly, the air is very humid, typically > 97.5% humidity and secondly, the evapotranspiration potential is very low as a consequence. When we have low humidity it means water is able to evaporate freely from the soil and grass plant leaf into the atmosphere, but when that atmosphere is closed to saturated (high humidity), there is very little potential for water to evaporate from the soil and turf surface. It is also incidentally why you sweat more in humid conditions because the sweat isn’t evaporated from your body.

The point of this part of the blog is really to look at how much potential there’s been to evaporate moisture into the atmosphere. Now I appreciate if I present rainfall vs. E.T data, it’s an imprecise equation because not all rainfall stays in the soil, some is washed off / shed when a rootzone reaches filled capacity. That process is obviously entirely dependent on the characteristics of the rootzone. Since it is difficult for me to take this into account as a humble blog writer in Market Harborough, you’ll just have to tut at the flaw in my figures but I think the message is still pretty clear.

Below is a graph of monthly total rainfall and E.T recorded by a Davis Vantage Pro 2 located at Great Dunmow, Essex. Again it would be great to present lots of data from all around but that’s tricky and beyond my time capabilities. You’ll get the gist from this graph though…

So as we can see, the last month that we experienced significant E.T was September 2020, where we had a rainfall : E.T ratio of 1: 3. What this means in simplest terms is that for every 1 mm of rainfall we had in September, we experienced 3 mm of evaporation, so the ground would have been able to dry out. By October that ratio had reversed to 4.5 :1 in favour of rainfall. A dry November got us back on track with a low rain:E.T ratio of 2.1 :1, but things really went to pot in December and January with respective rainfall : E.T ratio’s of 12.3 :1 and 8.6 : 1. Obviously for these months the ratio was tipped so much in favour of rainfall that rootzones became saturated and more to the point, stayed saturated with precious little evaporation.  February if you remember (it was only last month you know 🙂 ) was cold and dry and we recorded at this location an even ratio of rainfall to E.T. March 2021 is currently showing slightly less rainfall to E.T at 0.92 :1, so again we will have seen a little bit of dry down of the soil, but not much considering the very high moisture status we experienced in December 2020 and January 2021. So the bottom line is ground conditions are still saturated and especially where the rootzone has high filled capacity and received more rainfall than we have in this location. I’m talking about the west and north specifically where this will be the case. The surprise for me is that here in The Midlands we have had a reasonably dry month (rainfall total-wise), but obviously with high humidity, the E.T has been low and dry down of soils slow, so everywhere still feels wet.

If you added up the rainfall and E.T since Sept ’20 to y.t.d March ’21 for this location, we would show 477.8mm of rainfall vs. 208.9mm of E.T, which is what I’d expect for this period of the year, more rainfall than E.T. The craic though is that although in this location we would have had a pretty dry February and March, we still have some drying down to do and I’d be hopeful that this will come in April when the E.T normally out-scores the rainfall by some margin (usually to the point where we are clambering to get systems opened up and water on to our surfaces !)

Plant Nutrition

As discussed last week, we have had two bites of the cherry really in March with a mild (ish), wetter start to the month which was more conducive for granular fertilisation and then this cool, drier phase where low amounts of foliar nutrition was / is most effective. Come the last week of this month we swing back to granular with the promise of milder, wetter weather and high wind speeds negating the possibility of spraying. This is I think typical of the March / April period and its really a case of picking your nutrition, identifying a weather window specific to application and going for it !

Insect activity

Well there’s a lot of pecking going on now on outfield turf particularly as both Leatherjacket and Bibionid grubs feed close to the surface. The main culprits are of course the Corvid species like Crow, Rook and Jackdaw, who all have young in the nest and therefore eager mouths to feed. Some Badger activity as well I can see on the various FB and Twitter posts. Some of these areas have of course received a control but when you look at the variation in size of grubs present and their respectively different life spans, it is very, very difficult to control all of these grubs with one spray. I often wonder what those areas would look like if they had received no application. A lot worse I think.

Disease activity

Last week saw a north-south and west-east divide in the weather with the west and north closer to the centre of the high pressure. These areas picked up milder conditions and with the associated high humidity, we also saw some Microdochium activity across Ireland and sin Scotland as well with nominal amounts in the cooler south and east. That spike in activity will decline quickly this week for the north and west as that cooler, low pressure system introduces rain, wind and lower temperatures into the disease equation. For the south and east where we will hang onto the high pressure for longer, we have the opposite, with some higher activity expected through the first part of this week due to heavy dews and light overnight winds. This will drop off as we get to mid-week as that more unsettled weather spills south and east.

OK, that’s me done for another week….

All the best.

Mark Hunt