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Writer's pictureMark Hunt

November 21st



Out fly fishing at the weekend on my last trip to Eyebrook Reservoir before the season closes and I ended up being stuck right on the boundary of some North Sea Haar and drizzle. Took this picture just as it rolled in across the hills behind me and we went from mild and pleasant in this picture to cool, damp and mizzly in the blink of an eye. East of us had a dismally dull and cold day, but to the west, it was lovely. Fortunately I caught :)


Looking out to the west today though and it is a different story !

Mother Nature is certainly in catch up mode rainfall-wise currently and for sure we need it because water levels are still compromised by the drought of this summer. I saw a couple of Horse Racing headlines recently that discussed that mythical entity, 'going' and how despite the heavy rain, courses are drying up 'super quick' afterwards.


Well it certainly isn't down to evapotranspiration because as you can see from this snippet, it is definitely a one-sided equation currently comparing rainfall with E.T ;

So that's 81.8 mm of rain so far this month vs. 7.72 mm of E.T...


So if the ground is drying up fast it must be due to draw down as moisture permeates the dry soil layer underneath. I drove back from Elland Road last week where I was talking at the BIGGA Regional Northern Conference and we had a 20 mm+ rainfall day.


The rivers were over their banks and water sat in the fields. At first glance they appeared saturated but I wonder how much of that standing water is due to a dry (and probably hydrophobic) soil layer below, perching the moisture above it ?


At the end of the 1976 drought, we had 4 consecutive months of 100 mm + rainfall...well we have had 2 1/2 wet months so far and maybe we are now overdue a cold spell ?


General Weather Situation


Well if you look at the above GIF's you can see we have two low pressure systems dominating the weather and with a blue colour to boot, so that means cool / cold. Cold enough in Denmark to bring the first dusting of snow and a ground frost here as well.


So this week is looking windy, wet and unsettled with plenty of rain for everyone starting today with that rain front moving diagonally over the U.K & Ireland. So Monday looks to be wet, windy on occasion and that rain clears from the west during the day with Scotland missing the worst of the rainfall for a change. More rain will try to push in later to the south west of Ireland, Wales and England but it looks to make little progress overnight as another front pushes it clear by morning. Temperature-wise, typical of November really with 6-8°C, the norm.


Tuesday promises a hiatus between one storm system and another with a drier, more settled day and some sunshine. Lighter winds, but remaining on the cool side with 6-8°C typical and some cloud cover as well. It's only a stop gap day though because we already have more rain fronts building out in The Atlantic and the first of these will make landfall into Kerry on Tuesday evening, bringing heavy rain across Ireland, The South West and Wales overnight into Wednesday as that rain front crosses The Irish Sea. By dawn on Wednesday, that band of heavy rain is clearing the west and Midlands of Ireland but firmly entrenched across the western half of the U.K. So a very wet start for the west, Ireland not so bad after the main rain front has passed but they'll still be showers across western-facing coasts of the Ireland and the U.K. A wet second half of the day I think for central and eastern areas on Wednesday with winds strengthening to gale force and pushing round to the south west and introducing milder air as well. Scotland picks up this wetter second half of the day and with cooler temperatures up north, I expect it to bring the first snow to The Highlands.


Thursday sees more rain move across Ireland overnight into Thursday morning, but across The Irish Sea we will have a largely dry start to the day, albeit a breezy one, except for Scotland, which will hang onto the overnight rain. It won't stay dry for long though because that rain will push into the western half of the U.K during Thursday morning and quickly move eastwards. So a wet and windy day for us all on Thursday, but a milder one as that south westerly wind pushes temperatures up to 11-12°C.


Closing out the week on Friday and we have a drier day to finish the week on after showers along western coasts fizzle out during the day. The departing low will swing the wind round more north westerly so that'll chill things down a little, back into high single figures, but otherwise a dry one for the U.K & Ireland.


So the weekend is dominated by a rain front crossing Ireland on Saturday and reluctantly clearing Leinster on Saturday night, a wet day for Ireland and some rain around across North Wales / Northern England as well. Elsewhere, largely dry and with that wind swinging more south / south westerly, a mild one as well, with temperatures breaking double figures in those strong winds. Overnight into Sunday, we see rain crossing Wales and the rest of the U.K, but it should be clear by morning, which is grand as I have a long coastal walk planned out with a key brunch stop at The Two Magpies, Blakeney ! Some showers remaining across the east of the U.K later on Sunday but otherwise milder, remaining breezy and largely dry.




Weather Outlook


Well next week's weather starts with something we haven't seen for awhile, a high pressure system ! So that means drier, colder I think and easterly winds.


Hmmm, haven't had them for awhile either...

Let's hope it whisks over some flocks of Waxwings from Scandinavia as we overdue a visit of these beautiful birds, as they usually hitch a ride on winter easterlies to feed on our berry crop.


Now those easterlies look set to be a feature of our weather all through next week and possibly beyond, so I think that means cool, dull but crucially largely dry. I say 'largely dry' because this type of weather system often pulls in Haar and cold, wintry showers from The North Sea and I can see this happening as well, particularly at the end of next week. So a real taste of winter for us all maybe !


By the end of next weekend, that high pressure is threatening to pull down some colder northerlies as well and this could open the way for easterly and northerly cold air to push into the U.K & Ireland for the first part of December.


The odds on a White Christmas may just have got shorter not that Paddy Power is running a bet this year (bah humbug)

Agronomic Notes


So I thought I'd revisit a theme from the late summer in this week's blog and look at how our water table is recovering and maybe how much it still needs to go ?


Now it doesn't really affect Scotland, Ireland or Wales because I think they're pretty much back to where they needed to be, but I don't have the data to back up that statement, so it is at best, an educated guess. It does however take a lot more rain than you might think to rectify the effects of our hottest, driest summer (in places).


The above picture is Yellowstone Bay on Rutland Water's peninsular. It is a favourite walking destination of mine, not least because it's a good, year round surface and you have a view of water most of the way round and that's where I'm most at home.


The images above were taken 16 days and 63 mm of rain apart and for sure you can see the water is starting to edge up the shoreline. It has a long way to go though and with a drier spell kicking in from next week, it certainly won't be close to where it needs to be by Christmas.


When you look at the soil moisture deficit / surplus scenario that we have currently, yes we are undoubtedly heading in the right direction, but no, we aren't quite there yet. If I had more time I'd dig out some more useful information on borehole levels but perhaps that's for a later blog.


I picked 3 locations for my BIGGA talks recently and looked at a simple rainfall vs. E.T on a monthly basis and it spoke volumes. Now it is a simplistic comparison and dependent very much on how that rain falls (rain rate in mm per hour) and the characteristic of the soil to drain, but it offers a yardstick.


So here's how the year has panned out at one of those locations, down in Sevenoaks, Kent.

Firstly, I had to double check that November rainfall total because it's 80% more than we have had here in The Midlands this month !


Well just by this simplified model of rainfall and E.T, you can see we are heading the right way to reverse the damage of the summer. Now of course when we have deluges of rain, it tends to wash off rather than permeate in, so this is definitely over-stating the extent of recovery. That said, most of the heavy rainfall hasn't been at extremely high rain rates (see below), so you'd think there's a good chance of this rainfall adding to the depth of moisture saturation in the soil profile rather than shedding off ?



Cold, dry springs and aeration


Another point I'd highlight is the relationship between monthly rainfall, E.T and growth in the spring.


Look at April, we see 10.4 mm of rain and 71.07 mm of E.T, which means we are running at a significant deficit. The soil profile will be drying out from the surface downwards and putting the grass plant under stress.


Why then do we insist on aerating in the spring ?


I will clarify this statement almost immediately.


Why do we think we can get away with removing or trying to remove significant amount of O.M in the spring, be it with the Graden, large diameter hollow core or the like ?


The simple fact is we don't have the rainfall, we more often than not don't the growth and we have significant plant stress.


Looking at the chart above, you can see that the total monthly Growth Potential in March at this location was 5.8, that's out of a theoretical maximum of 31. (31 days of optimum G.P (1.0)). The figure for April was 9.3, out of an optimum monthly G.P of 30.


Putting that into % terms, we have March coming in at 18.7% of optimum growth and April at 31%.


Compare that to August and September, where we are at 91.0% and 72.6% respectively.


So for me, March and April is definitely the time to aerate, but not in a way that requires good amounts of growth to recover from. So compact vertidraining, micro-tining, solid tining, etc are the order of the day and I'd be favouring anytime from January onwards for this provided ground conditions allow.


January ?.............. yep January, because the grass doesn't grow by the calendar, so why should we maintain it by the same ?. If you get a weather window in January and aerate, then you have longer for recovery before the conditions begin to work against you (usually towards the end of March)


OK, that's me for this week as the rain hammers down outside and the temperature drops to the more normal November figure of 5.3°C !


Next week, there won't be a blog as I'm having some downtime in Norfolk, timed to coincide with the last of the mild winds maybe ?


Catch you on the flipside and all the best


Mark Hunt


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Martin Ashdown
Martin Ashdown
Nov 22, 2022

Great blog as usual, thanks Mark.

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kevin boot
kevin boot
Nov 21, 2022

A very interesting and informative blog. Thank you

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