October 19th

Hi All,

Back rested and refreshed (?) from a lovely break in Norfolk. As you can see from the pic above, the weather was ‘mixed’ but then what can you expect for October ?

The pic above is taken looking over the salt marshes towards Holkham Hall from Burnham Overy Staithe. If you know the area (and I think quite a number from our industry visit Wells and the surrounding area), you’ll know there is a sort of timeless feel to the place. I’ve been going here since I was 4 years old, it is therefore a place packed full of memories and the fact that it’s pretty much the same as it was over 50 years ago is reassuring to me in this often chaotic and volatile world. Having a bolt hole to reset yourself is essential I think for mental well-being, well this is one of mine 🙂

I had to laugh because the day after I left Norfolk, herds of twitchers descended upon the area (Stiffkey to be precise) to view a very rare visitor to our shores, the Rufous Bush Chat. Normally a tropical species, this dull brown bird evidently took a wrong turn from southern Europe and ended up here. I walked through Stiffkey the day before, probably straight past it and maybe wondered what that LBJ (Little Brown Jobbie as my dad used to call any small brown bird he couldn’t identify) was. Apparently the last one that visited the U.K turned up in a Butlins camp in Skeggie in the 90’s….Poor thing, that must have been quite a shock for it ! 🙂

Talking about resetting, the weather is up for the same this week as have a mixed bag due with plenty of rain around, some milder, humid air (which may cause us some disease issues mid-week) and at the end of the week / weekend, some really strong winds heralding the arrival of a succession of Atlantic storms for the 2nd half of the month. Without further ado let’s get onto the weather as tempus fugit today.

General Weather Situation

Starting off today we already have a wet start for Ireland and Scotland as rain moves slowly across the country. Further south across England and Wales we have a nice start to the day with light winds and some autumn sunshine. Through the morning, the rain over Ireland and Scotland will slowly move north and east which means for a time central and eastern Scotland will dry up but not for long as more rain arrives during the afternoon. Sadly the rain over Ireland will continue on and off for all of the day with the heaviest occurring this morning. So England and Wales look to stay dry for most of the day save for a few showers nudging into north and west Wales later in the day. Temperature-wise 13-15°C in the south, but a couple of degrees down on that under the cloud and rain. This milder air is feeding in on a southern wind.

Onto Tuesday and the Atlantic low pressure that brought Ireland the rain on Monday will be sitting just off Kerry and pushing rain across the U.K & Ireland. So at dawn tomorrow we will see a band of rain across most of the U.K, clearing the west and south west as it moves eastwards. Ireland may start dry (ish) but the centre of the low will push rain, some of it heavy into the south west of Ireland and this will move north and east through the course of Tuesday morning. During the morning, the first band of rain will move eastwards and clear England and Wales leaving behind a nice, warm autumn day with sunshine. Further north we see rain continue over Scotland  though this will clear all but the most northern areas through the morning into the afternoon. Another wet day for Ireland as p.m. sees that rain covering most of the country. As we move towards dusk that rain clears the south and west of Ireland and pushes into south west Scotland and north west England, with a further band of rain pushing into The South West. Despite the strong south westerly wind, it’ll feel much warmer than of late with temperatures in the high teens across England and Wales, so a really good drying day hopefully.  Mid-teens for Ireland and Scotland with that rain and heavier cloud cover.

Onto Wednesday and overnight we see that rain track north and west across The Irish Sea into the west of Scotland and a new Bay of Biscay low pressure slink up to bring rain, some of it pretty heavy along the south coast and into south east England. Through the course of Wednesday morning the rain will push northwards reaching The Midlands in time for rush hour. Ireland on the other hand will have a drier, if dull, start to the day with some showers across Kerry and Clare. Definitely a case of the boot being on the other foot because Wednesday will see rain over England and Scotland merge to place most of the country under rain and heavy cloud by the afternoon, whereas Ireland will stay reasonably dry save for those western / south western showers. As one low passes north and the other dissipates, we will see the wind drop in intensity and shift round to a more north westerly aspect which will mean a cooler day with temperatures in the low to mid-teens.

Thursday sees a quieter day weather wise with both low pressure systems moving out of the picture. They’ll leave behind a scattering of showers from The Pennines south across England and Wales early doors. These showers will push up from The South West and Wales and move north and east through the course of the morning. In contrast Ireland will have a much nicer day with some breaks in the cloud to reveal some nice autumn sunshine, the same for Scotland. The showers over the lower half of the U.K will fizzles out as we go through Thursday afternoon to leave a dry picture for the end of the day almost everywhere. Thursday will see the return of a north easterly wind so that’ll drop the temperatures down from the highs of earlier in the week and keep things in the low teens, high double figures sort of way, cooler in that wind then despite more in the way of sunshine for most places.

Closing out the week on Friday we see a new, very intense low pressure sitting off Greenland. This will push rain in overnight across Ireland and by Friday’s rush hour it’ll be mainly affecting the west of Ireland with sunshine and showers for the east. Across The Irish Sea, Friday will be a dull sort of day, maybe brighter in the west initially across The South West and Wales, but by lunchtime this brightness will have been replaced with some potentially heavy rain for Wales and a whole raft of showers pushing into the western coast of the U.K and moving eastwards into more central areas during the early afternoon. Scotland will see a dry start and then showers building from the west but like the rest of the U.K, it won’t reach the east till later and some eastern areas may miss the showers all together.

The GFS projection above is for midday on Friday and it really sets the tone for the first part of the weekend. You can see closely packed isobars which indicate a very strong south westerly wind speed for the west of Ireland during Friday and then all of us through Saturday. Despite the close proximity of the low pressure, Saturday looks like being a reasonably dry day, albeit a very windy one for the U.K, but for Ireland you’ll get the rain associated with the low pressure system for most of Saturday I am afraid 🙁 During the course of Saturday night / Sunday morning, this rain crosses The Irish Sea into the U.K and by Sunday morning some areas will still have it present, whereas Ireland and the west of the U.K will be sunny and pleasant with lighter winds for all on Sunday. This rain band will be very slow moving and so for a line up from The Isle of Wight to The Wash we may see some pretty heavy stuff around with high rainfall totals before it eventually clears away. Scotland looks similar to Ireland weekend-wise with a very wet Saturday across western and central areas followed by a much better Sunday, though still with rain across the west. As you’d expect with a strong south westerly airflow, temperatures will be reasonable over the weekend with low to mid-teens for England and Wales and a couple of degrees lower for Ireland and Scotland.

Weather Outlook

Above is the GFS projected output for next Monday and as you can see we sit in a cool trough with milder air to the south west and cooler air to the north west. This doesn’t tell the whole story though because it’s what’s lurking just out of the frame across The Atlantic that will set a pattern on next week’s weather or more precisely, the 2nd half of next week.

The above for Wednesday next week shows a really intense low pressure, with 926mb projected at its centre.

Look how tightly packed those isobars are, so windy, damagingly so if it were centred over us. (which it isn’t luckily as the projections stand currently)

So putting some flesh on the old bones, next week starts of cool and reasonably settled with some showers around for the north west on Monday, otherwise it’ll be dry which is good because a lot of clubs will be clearing up leaves !!. By Tuesday that low pressure (Bella ?) will swing in a heavy rain front across Ireland and then the U.K through the course of the day. More rain showers for Wednesday before an intense low pressure pushes into Ireland and the U.K and brings heavy rain and strong winds on Thursday, with maybe a drier interlude on Friday for some areas before more rain pushes into the west and east as that low rotates in the trough, with the winds easing as we reach the end of next week / weekend. That low pressure will take until Sunday to work itself out of the U.K and Ireland, so possibly a more peaceful and settled Sunday next weekend. Cool though in that trough pattern so I’d expect 10-12°C to be the norm.

Agronomic Notes

Disease pressure

Looking at this week we have a pulse of mild, humid air pushing up on south westerly winds and this will cause disease pressure to ramp up from Tuesday onwards. That said it won’t be for all areas because where we have wind and rain (Ireland, Scotland, north west England), the pressure will be lower.

But for central areas and Wales, we will see some mild overnight temperatures in the low teens on Tuesday and Wednesday night dove-tailed with high humidity and plant leaf wetness.

In other words perfect conditions for disease activity.

Below is a projection of disease pressure on sheltered locations (so it represents a worst case scenario really) for 3 specific areas ;

The top graph for the south of England shows how the disease pressure builds from Tuesday night and lasts into Friday before dissipating with the arrival of the winder weather for the end of the week / start of the weekend. If we go further north to Birmingham, we see the disease peak is shorter and lasts from Tuesday night into Thursday morning. Across The Irish Sea, the windier and wetter weather forecast for Ireland and Scotland will mean a much shorter, less aggressive peak of disease activity. So it looks like we will need to rely on fungicidal protection in the south of England and up to The Midlands possibly if our prediction is accurate but the further north and west you go, the less reliance they’ll need to be.

It is as we know typical of October to feature disease peaks and with the potential for higher overnight temperatures this month compared to November, it is something that we just have to learn to manage.

Stop disease now and you’ll have less issues later into the winter. That said, it is harder with the reduced efficacy of current fungicide offerings, particularly in the UK.

Worm activity and lack of dry down time….

This year is proving to be a very tricky one in terms of managing these critters. The milder and wetter conditions in September and October have meant there’s been a lot of casting worm activity and with the lack of drying days, this has proved very hard to manage, particularly on outfield areas. The lack of drying days as we progress into the autumn has a number of knock on effects. Longer periods of leaf wetness encourage disease, you get less dry cuts and of course worm casts don’t dry out so they smear when rolled over.

I’ve charted out the weekly E.T from September 2020 to the present day and also the number of minutes of leaf wetness per week so you can see how much of a change there is as we progress from September to October, with the shorter days and consequently longer nights.

So you can see from the above graph showing the total E.T over a calendar week, how marked the drop off is in drying potential as we move from September into October…The knock on effect in increased minutes of plant leaf wetness (from rainfall and dew) is clear to see as well in the graph below ;

OK, I don’t have a solution to the issue, it’s one we will need to adapt to especially on outfield where the cost of carrying out separate operations to reduce the effects of casting worms is significant and all set against the backdrop of Covid-19 and increased restrictions / reduced resources. That’s tough.

From a greens / fine turf perspective of course we can mitigate the effects of plant leaf wetness by using dew dispersants and when you compare their cost to that of a fungicide, it really is something to think about going forward if you’re not using them already. Looking at the scenario in terms of disease pressure for the south of England / central England / Wales this week, you only really need them to bridge the gap of 3-4 days and prevent scarring, for them to earn their keep.

Something to ponder maybe ?

All the best till next week…

Mark Hunt