Hit and miss downpours

A warm, humid and unstable atmosphere will exist over the British Isles in the coming days – the recipe at this time of year for some heavy bursts of rain and thunderstorms.

A slow-moving area of low pressure will drift around through the weekend into the early days of next week, with areas of rain and low cloud encircling the low. There’s some dry weather too, and a little sunshine, but generally hazy.

Rain and drizzle over northern England on Saturday morning will tend to drift away north and westwards, with drier conditions following. Extensive hill fog to low levels, particularly in eastern Pennine areas early morning will gradually lift, and some sun will break through. One or two areas of showers will then form through the day, but not everywhere will see them, so it really does just come down to luck of the draw.

The model chart shown below is the best indication we have for where showers will form on Saturday afternoon.

Showers are likely to become more widespread and potent from Sunday onward through Monday and Tuesday, forming generally into the afternoons, when some slow-moving torrential downpours with hail and thunder are to be expected down the spine of the Pennines. Again, hit and miss, but the risk is greater and more widespread of catching the downpours. 20-30mm+ in an hour in some locations will cause local flash-flooding in these situations.

Things are due to become quieter from midweek onward, as pressure slowly builds from the west, and a couple of drier days are likely by Thursday-Friday.

There’s then a question mark about how soon pressure falls again from the west, and whether further unsettled conditions move back in for a time.

Temperatures will be better than recent values at least, with maxima commonly into the low 20s, with overnight values no lower than 10C. Damp air will hang around, so early murk is always a possibility in the hours after dawn.

At least our golf courses are greening up nicely now, and the putting surfaces have welcomed the drink. Let’s hope our weather machine knows when to turn the taps off…

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What a difference a week makes!

A week may be a long time in politics, but it’s also certainly a long time when it comes to our glorious British weather!

We have moved from high pressure and endless days of sunshine through much of May, to the prospect of the first weekend of June being plagued by heavy downpours.

Useful rain at least, as many courses were certainly in need of a drop, so maybe we shouldn’t complain, but we could do without reaching for the brollies and wetsuits for Saturday’s golf!

Here’s the latest weather plan for the next few days:

Low pressure is pivoting around over the North Sea into the weekend. Cold air at upper levels in the atmosphere means things are quite unstable. This produces frothing cumulus clouds, and ultimately some heavy and thundery downpours.

This upper ‘trough’ will be over central-northern England through Friday and Saturday, with scope for showers to locally band together due to local converging winds.

This means there is still a degree of ‘hit and miss’ about who gets what in terms of downpours. A few miles either way can make a big difference! A realistic 5mm in half an hour is to be expected, with 10-15mm in the day if you get hit a few times.

Friday is likely to see showers pretty widely, so you’ll do well to miss everything. There’s a tendency for clusters of showers to concentrate into areas east of the Pennines in the afternoons in these cyclonic northwesterly episodes, but there will always be a few bands of showers which form around Lancashire and try to move into the western Peak District and Staffordshire. Watch out for thunder and lightning because things are lively enough for that in the current setup.

By Friday night into Saturday, northwesterly winds will strengthen, with gusts toward gale force, 35-40mph, which will bring some debris down from the trees. A more organised zone of rain is expected to pivot southwards across northern England into the Midlands from pre-dawn into Saturday morning, lasting several hours. This combined with continued strong winds and chilly temperatures only 6 to 8C means it’s not looking so clever for your morning socially distanced three or fourball…

As this system pivots in on early Saturday, a 6-8 hours rainfall accumulation of 15-25mm in the western Peak & Pennines is looking believable, as strong west-northwest winds drive into this part of the world, and throw their moisture at the hills.

I say this with appropriate caution, but it’s a weather situation which is not far removed from the one which brought the infamous ‘snow stops play’ to Buxton in June 1975 (see charts below). Delving into the archives, I reckon that airmass was inherently more purely ‘Arctic’, whereas this one is merely Scandinavian in origin. It has come from the same sort of weather setup though, with a cyclonic northerly regime in charge for a few days. It would only take a few more degrees worth of temperature fall within a heavy rain band early Saturday to find something sleety in the mix. I think you’d have to go up Cat and Fiddle or onto Kinder plateau to find this, but it’s not a million miles away.

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By Saturday afternoon, things should be breaking up into showers, but the odd lively one is still likely. The worst of the winds are expected to ease too, and temperatures should recover toward 13 to 15C in any sunshine.

By Sunday, pressure begins to build, and whilst it stays cool with a risk of showers, they will likely be more scattered, with variable cloud and sunshine. Highs of only 13 to 15C are still not exactly summer-like!

Early next week is expected to see high pressure nudge further across Britain, with less strength than recently, but should be enough to give some dry days again. An odd shower or weak frontal band giving patchy rain will remain possible.

In the longer range, most trends favour high pressure lying to the north/northwest of Britain, whilst low pressure wants to be focused to the south over Europe, so east or southeasterly patterns may be the most common. Temperatures trending upward with time. Some showery activity is likely, but depends just how the various weather patterns shuffle around.

We could do with some rain to keep things lush, but not too much to spoil our summer!

Sunshine all the way this weekend

Things are very much set fair into the weekend, as high pressure dominates across the British Isles.

It’s a pretty simple forecast in the short term, with lots of sunshine and blue sky. A chance of local mist pockets just around dawn, but those will soon burn off.

Temperatures rising into the low 20s Celsius into the afternoons, and some spots in northwest England to the lee of the Pennines may nudge 23 or 24C.

A general light east to southeasterly breeze will prevail, so eastern parts of the Midlands will tend to be a little cooler, with the air moving inland off a cool North Sea.

Overnight temperatures will dip into single figures out of towns, and some spots over the weekend may find themselves around 5C in Pennine areas just at dawn, so a dewy start is to be expected at first light.

Into next week, it gets a little more complex, as pressure falls a little, with the scope for isolated pop-up showers forming on some days. Most indications make these very hit and miss, with a mostly dry theme still looking likely into the first week or so of June with high pressure still nearby.

One or two forecast model simulations do make showers pop up more widely with time, but trust this at your peril if you’re itching for rain… It may come to nought for most places!

The temperature will ease back a bit next week as the air mostly approaches the UK from the north or northwest. Expect a bit more cloud, and maxima in the 16 to 21C range, whilst overnight will typically fall between 5 and 10C.  Chillier nights are possible later in the week, so keep an eye on that one.

The likelihood into the second week of June is that high pressure is stationed to the west of the country with northwesterly weather patterns prevailing. Some suggestions lean toward the Atlantic patterns trying to make a stronger comeback for a time. I would suggest for now that things are likely to stay more often dry, but looking rather on the cool side on some days.

This Saturday afternoon’s maximum temperatures are shown below.1

 

 

Summer thinking; not much rain ahead

Spring 2020 has been notably dry, following the deluges of last summer, autumn and winter. It looks like the dry theme is here to stay for a while longer. Are we looking at a repeat of the parched fairways of 2018?

Weather tends to go in cycles and patterns, and I have studied this extensively over the years. There is much short term variability mixed with longer term trends which manifest themselves over a series of years for familiar weather patterns, before things switch gear and we go into another weather ‘mode’. Then there’s much longer term variability in the British weather driven by multi-decadal patterns occurring within the north Atlantic Ocean. That’s before we even consider any human induced climate changes!

It wouldn’t be a surprise to see our current dry spring drift into a dry summer based on historic patterns. Regardless of winter rainfall, dry and wet summers tend to cluster together, with the 1990s seeing batches of dry summers, and of course the two back to back years of 1975-1976 which sit high up in weather folklore.

The 2000s were much more sparse with frequently wet or thundery summers. The 2007 to 2009 years were excessively wet. 2012 was also very wet, then after a dry July in 2013, the middle 2010s were mediocre rather than extreme, lacking any significantly long dry spells until we arrived at 2018. Last year started off dry in the spring, but by June things were often wet. July had it’s ups and downs before the heat spike followed immediately by the heavens opening and dramatic flooding.

So where do we go into summer 2020? There’s never an absolute answer, and things never repeat exactly, but there’s some patterns which we can look for.

My suggestion is that we stay on the drier side into early summer, maybe interspersed by the odd ‘nibble’ of Atlantic patterns, but soon back to building pressure. Higher than average pressure means drier than average weather, and that seems to be on the cards based on latest computer modelling.

Deeper into summer, I suspect some lively thunderstorms will get going again, perhaps a situation where most of a month’s total rainfall occurs in just a few big events, leaving still a good deal of dry weather. By August, I wonder if we’re struggling, and unsettled patterns are more common. August is climatologically a wet month in British weather patterns despite our idea of it being the holiday month! Very dry Augusts are quite rare.

In the short term, there’s a small but useful amount of rain to come on Friday morning as a frontal system sweeps through. Very windy conditions too, and blustery west to southwest winds will take us into the weekend. A few squibs of showers will come from the west, most frequent in areas north of the Peak District, leaving places nearer to the Midlands more generally dry.

The week ahead sees pressure build from the south again, and any weather fronts off the Atlantic will focus themselves on western Scotland and sometimes the Lakes & N Pennines, with just the weak tail end of fronts grazing our part of the world with little or no rain of note.

Temperatures will be a little warmer than average thanks to southwesterly air, although cloud amounts may vary day to day, changing the feel of things through the week.

Most indications keep pressure fairly high to the end of the month, with perhaps a weather system floating around later next week, but unlikely to come to much.

Total accumulated rainfall up to 1st of June from one of the standard forecast models is shown below.

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Golf returns, any useful rain?

Golf has returned, and lets hope the situation in the country stays safe enough for us to continue doing this fully into the summer. I’m sure we’re all more than willing to keep to the various restrictions to enable us to get out and enjoy the game we love.

So what does the weather have in store for both players and greenkeepers in the near future? Here’s my latest summary relevant to the Midlands and the south Pennine areas:

Still often dry, warming up next week.

Our British weather likes to give us the run around, and we often swing between being too wet and too dry, and less often ‘just right’! The soggy winter is now a distant memory, and recent weeks of lockdown has seen things dry out significantly, to the extent that we could now use a drop of rain!

The outlook for the next 10 days doesn’t have much rain in the forecast however, and it stays dry for most through to Saturday, barring a local squib of a shower. 

A weather front is then due to come in from the Atlantic as we move into Sunday and Monday. Most of this rain is likely to be aimed at the northwestern parts of Britain, although some is expected to spill into the Pennines. The Lancs/Yorks corridor may get rainfall in a couple of sustained periods during Sunday-Monday, totalling 10mm over the western Pennine hills north from about Manchester, with less further east.

There will be generally less rain the further south you are, with 3-5mm currently modelled for central parts of Derbyshire and the Peak District in 48 hours or so Sunday-Monday, whilst into the lowlands of the Midlands, more likely barely 1-2mm.

Beyond that, high pressure is expected to build from the south, with dry conditions looking likely for most of next week, and becoming increasingly warm as the wind flow turns to the south, beginning to feel rather humid too. 

Temperatures will be back to 15 to 17C this weekend, then into the low 20s Celsius into next week, and some spots may nudge 23 or 24C by midweek if sunshine comes out widely. The current risk of overnight frost will disappear by the weekend onward.

Further ahead, signals are for warmer than average conditions to be a common theme late May into early June, interspersed with perhaps the odd thundery breakdown coming from the south.

Overall though, conditions look more often dry in the weeks ahead. Sometimes as we move further into June, we see a so-called ‘return of the westerly winds’, which can bring unsettled weather following these drier springtime patterns.

We’ll have to wait and see if that will materialise this year.