Beautiful to see the first signs of spring out walking yesterday though there won’t be much spring-like about the weather this week as we pick up some pretty cold air across the southern half of the U.K in particular.
February is traditionally our coldest month of the year as we all know so I had to admit to a smile when I saw a headline proclaiming “coldest week of year coming up” in a tabloid yesterday. Wow that must have taken some thinking about….It’s not a straight-forward case of cold and dry this week because we have low pressure sitting north of us and that will push some moisture into Scotland and the like through the week.
Ok onto the detail…
General Weather Situation
So Monday starts pretty dry everywhere but with a north east wind we are likely to see some snow showers pushing in from The North Sea into eastern and south eastern parts through the day. Areas most likely affected are the South East, East Anglia and Humberside. Otherwise a calm, dry and settled day just about everywhere with sunny intervals breaking through later in the day and a quiet, north easterly wind. Those snow showers look to drift in to eastern coastline of the U.K throughout the day but they’ll be pretty hit and miss so best to check your rain radar to see if any are coming your way. Later in the day we will see a band of moisture pushing in from The Atlantic bringing rain and wintry showers to the west coast of Ireland overnight. Temperature-wise 3-5°C is all you are likely to see on the old thermometer with a hard ground frost overnight leading into the day. (We were -1.6°C here)
Overnight into Tuesday and that front of wintry showers will be sitting across the east coast of Ireland, western and central areas of Scotland and north west England by the start of Tuesday morning rush hour with a lot of snow wrapped up in that moisture. As we go through the morning that band of wintry showers will sink south into Wales and eastern, northern England, however south and east of this it’ll be a dry, cold and bright start after a sharp overnight frost where temperatures are likely to drop to -3°C. We may just see some showers push further inland into The Midlands but we’ll see, currently this isn’t forecast. As we go through the afternoon those showers will sit in a band stretching up from Wales through northern England and across to The North East with Scotland clearing to end the day with a nice, bright, cold, clear afternoon and evening. Ireland will have a dry, bright and clear day after those wintry showers depart the east coast during the late morning but we may well see them make a return into Connacht and Donegal later in the afternoon. So another bright, cold and dry day away from those wintry showers and with the wind turning more northerly I’d expect it to feel even colder with temperatures barely breaking freezing in the wind, maybe 2-3°C tops.
Mid-week already, how time flies when you’re freezing your nads off and Wednesday promises another largely cold, dry and bitterly cold day with a penetrating ground frost overnight perhaps down to -4°C in areas. With the light wind swinging round to the north west, it’s the turn of western coasts to bear the brunt of wintry showers with Wales, The South West and the western coast of Scotland at risk through the morning. Dry, bright and cold everywhere else so a great week to crack on with winter project work if you are able. Cloud cover may persist over Scotland and northern England through the afternoon and this will thicken to bring some more wintry showers along north western coasts as we close out the day. Ireland looks to start dry, bright and cold but cloud cover will thicken through the afternoon, it should stay dry though. Again 2-3°C tops temperature-wise across the U.K and maybe 6-7°C across Ireland.
Moving into Thursday and overnight a weak band of rain and wintry showers has pushed into western Scotland and north west Ireland moving south and east by dawn. This moisture will likely fall as rain across Ireland as a change in the wind direction heralds in slightly milder air temperatures. As that moisture over Scotland and Wales meets the cold, continental air expect it to turn more wintry in nature. Through the morning that rain crosses slowly over Ireland and into the north west of England and Wales falling as snow over Scotland. This band of moisture is persistent and although it slowly clears Ireland during Thursday night it will turn more wintry in nature across the north and east of Ireland, Wales, the north west of England and Scotland pushing cloud before it. So a dry, bright and cold day for central and southern areas of England but through the day it’ll become cloudier as that band of wintry showers pushes moisture ahead of it. Similar temperatures to Wednesday with 2-3°C tops across the U.K and maybe 6-7°C across Ireland again.
Friday sees the highest threat of moisture to the southern half of the U.K this week with that band of rain and wintry showers moving south and east overnight so we may start Friday morning wet with a mix of rain, sleet and snow extending all the way down into The Midlands. The boot is on the other foot on Friday because after a soggy Thursday, Ireland and Scotland look to have a bright, cold and dry end to the week. Through Friday morning that band of moisture will sink south and east affecting all areas before it eventaully moves off into The North Sea by the late afternoon. Another cold and dry end to the day and that means a penetrating frost for all of the U.K and Ireland on Friday night I reckon with a risk of wintry showers still for the north west coast of Ireland.
The weather at the end of the week pretty much shapes the beginning of the weekend because with a bright, cold and dry night we will all have a penetrating ground frost to start the weekend. So Saturday looks cold, dry and sunny across all areas with a really cold northerly wind dragging temperatures down towards a negative windchill. So it’s a winter walk, wrap up warm sort of day if you feel disposed to do so, except for Ireland where I think you’ll see a dry first half of the day but increasing wind and cloud will push rain in for the 2nd half of Saturday. Sunday sees the wind swing round to the west and gather strength, particularly over the north of England, Scotland and Ireland so milder but more unsettled with an increased risk of showers for the 2nd half of the weekend.
So next week looks like it’ll start with a North-South split in the weather with the south hanging onto that cold, dry, high pressure for a few more days. The north and west will come under the effect of another Atlantic low pressure system which will bring unsettled, windier weather in from the off and a milder westerly airstream. At present it looks like this low pressure system will sink south and exert its effect across all of the U.K and Ireland as we approach mid-week settling into a strong westerly wind, milder temperatures and some rainfall of course.
As it’s the first blog of February it gives us a chance to look back at January and see what hand we were dealt.
GDD January 2018 – Thame Location
So we can see at this location we put on 30.5 GDD which is pretty normal really as January’s go and reflects some positive growth periods during the month, more on that later. No real point in doing a cumulative so we’ll cast our net around the U.K and Ireland and look at both GDD and rainfall.
UK Locations – GDD & rainfall data
The first point that is very obvious about the above chart is the huge amount of variation in rainfall levels with the Northampton location, the driest and Okehampton, the wettest.
The difference between the two is a rather mid-boggling 163mm !
There’s a clear west – east divide for the U.K when it comes to rainfall and as you’ll see from the Irish data, this is true there as well. Growth-wise we have evidence of a pretty cold January in Scotland with a GDD of only 6.8 recorded for Fife compared to our Thame location which showed 30.5 total GDD for the same period.
Looking at the growth patterns for the month we can clearly see the difference between 3 UK locations as we cover south to north…
All 3 locations show similar patterns of growth but not magnitude with the most southerly location warmer as we would expect. The phrase “No one size of hat fits all” is clearly true when we look at the potential for taking advantage of this growth by carrying out early organic matter removal / aeration. Clearly although Fife and Thame shared similar rainfall totals it’s obvious that whereas we would have seen some growth and recovery in the Thame location from any January work, we would have seen nothing in the Fife location.
Ireland Locations – GDD & rainfall data
Ireland follows a similar pattern in terms of GDD and rainfall but you can clearly see where the rainfall bias was !
So the east / south east coastal locations of Dublin and Wexford came off lower rainfall-wise, some 50-60% less than the west of Ireland that got clattered I’m afraid during the month of January.
Growth-wise we have the shining star that is Valentia with a GDD total of 67.4 compared to the lowest GDD in Claremorris and also Dublin of around 20. With temperature in January comes rainfall though and so the highest GDD location is also the wettest with nearly 10″ of rainfall 🙁
Again the same dynamic in terms of growth would have been present but with so much rain falling in January over most of Ireland I’d be doubtful if anyone managed to get some aeration done successfully even if there was some good growth windows evident as we can see below ;
In some locations, the period from Jan 22nd to Jan 29th showed some good growth albeit with a drop off on the 26th and 27th and this window was enough to provide some great response from early season-applied granular and foliar fertilisation.
I think granular nutrition is often more effective at this time of year because you have better resistance to leaching (particularly if the formulation is slow release, controlled release, organic) and better longevity as well.
You may ask “What’s the point of fertilising so early” but for me if you have such a growth window (and clearly not everyone did) then why not get the plant growing or ‘primed’ in readiness for growth ?
Any growth benefit gained now means less growth requirement once we reach the spring good and proper and with a propensity to have drier springs, using these windows now can be more reliable than those later into the spring, particularly from a moisture perspective. I’m going to guess that in the latter part of next week we will pick up a milder airstream and a return to growth and so if the grass plant is ‘primed’ it can take advantage of this whereas trying to kick start it during the window means an inevitiable lag.
There is a counter-argument I know that the grass plant growing the most at this time of year is Poa and by encouraging this plant to grow, you tip the balance in favour of it vs. other grass species. Of course on a lot of surfaces, Poa annua IS the dominant grass and so I could chuck in another counter argument which would be that growth at this time of year from Poa means better recovery from autumn disease scarring and a tendency to out-compete other plant species like moss. Like so many things in life it is horses for courses….
Ok that’s me done for another week, wrap up well this week with all that cold weather around and let’s hope that next weeks milder weather signal does indeed manifest itself.
All the best…