Maz

Cloudy start, very muggy with some spots of rain. Deposits of Saharan dust on cars and other surfaces. Hazy sun now and a rapid climb in temperature. Enjoying this spell, extremes of any weather kind are always interesting from my point of view. Also I love it when it’s sunny. So this spell is a win-win. Makes the kids more tired and grumpy though, which is not so good.

For an extended 4 month summer period, combine mid May to end June 2023, July and August 2022 and first half Sept 2023…that would be quite the combo for sun/heat/storm lovers.

The Deep Dive and 10 day trends really are brilliant. Go into a lot of depth, but made really accessible. When you think that we used to wait for the week ahead farmers forecast on a Sunday as the only slightly in depth view, and now we get these - not to mention all the model data on the web. Comfortingly the Met Office videos always cover the same issues and uncertainties being discussed on here (minus bias, hope casting and reliance on single operational runs!!). Coming back to the models - the video said it all. Hot until Sunday with various thundery chances, then a cold front from the NW whose timing is very uncertain. Enjoy!!

Yesterday there was some discussion about the lag between sun strength and the seasons. As an example, the first week of April has similar sun strength/day length to now and by coincidence also saw a sunny high with SE flow. Early April: Min 0c, Max 15c (was fairly typical away from windward coasts etc) Early September: Min 15c, Max 30c (maybe typical of this spell) This spell is clearly extreme, but the contrast with early April is clear

Shallow field mist this morning in prone areas near the river. Interesting with a shallow valley inversion setting up. It was noticeably cooler feeling in the valley bottom. However, was really pleasant. And it’s now another hot, blue sky day.

Tomorrow might be a day for foehn effect if there is a SE flow. Chester, Porthmadog, N Devon etc. Even the right locations to NE of Cotswolds/ Chilterns/S&N Downs might be favoured. Oh and W Scotland might see some surprising heat too….just like June 13th with Porthmadog and Cumbria laying to rest the 30c enigma.

Tarmac heating up across the country: Luton, Stanstead, Heathrow, Gatwick and Fairford airports all 27c or higher.... ...it's all fake news, I'm sure it's autumn everywhere else in UK!!! (tongue in cheek, in case that doesn't come across)

Purely from day length Nov 7 - Feb 6: Dark Feb 7 - May 6: Lengthening May 7 - Aug 6: Light Aug 7 - Nov 6: Darkening Weather significantly lags though due to stored heat/cold, especially in the oceans. Hence Dec-Feb, Mar-May, Jun-Aug, Sep-Nov is the best in the UK to my mind. Astronomical seasons just seem to out of synch with the light levels and natures response to that.

That’s our “heat pump”. Cut off low over Iberia. Significantly further east than the “heat pump” low off Portugal that gave the 40c last year. However, a similar pattern. Is it a pattern that will become more common with global heating? Or is it a coincidence?

Glorious day and looks like tomorrow will make it a glorious weekend. Clocks ticking on the “outdoor” part of the year, so definitely making the most of it.

My normal early morning walk/runs take me to some prone fields near the river Irwell. No mist this morning though, not even any dew. Shallow mists and heavy dew have been a feature right through July and August though, with the ground really wet, meaning even if the temperatures didn't drop much overnight, mist/dew readily formed. Some very atmospheric mornings. "Summer" like mornings (i.e. no or only a light dew and relatively mild feeling) have been restricted to June this year for the most part....and looking at the forecast, maybe the first week of September too! We will see.

Sunnier than I was expecting today. Very pleasant so far. Clouds are interesting today. Lower clouds that are building as the front moves in, are moving SE->NW. Higher level cloud moving the opposite direction NW->SE. Veering of the wind with altitude is a good sign of a front approaching. 180 degree difference seems extreme though.

I’m Summerseat based. Hope you enjoyed your day on the trains. Was better weather than I expected….thunder is rumbling around now though and the covers are on at the village cricket.

As a SAD sufferer I will be very happy to have some sunny weather in September, and indeed beyond in autumn. Increasingly as sun weakens it is not as simple as high pressure equals sunny though. For me sunny periods in Spring and Autumn are doubly valuable in staving off SAD. Even bad spells in summer have plenty of light.

I'm not sure I agree that the models have "failed miserably". For this week, and again next, there have consistently been a significant but minority of ensemble members showing strong plumes (admittedly, disprportionately including the operational runs) but the majority showing either the heat dome over the continent as a "near miss" for the UK or a glancing blow to the SE only. All within the general envelope of high pressure to our east and low to the west. The general pattern holds, the majority position is unfolding this week and seems more likely next week. The more stable and "boring" anomly and Hovmoller charts have also consistently supported that. That said, there is clearly something going on that is throwing the modelling. Operationals and ensemble members keep throwing up a highly amplified pattern with a cut off low near Biscay or in the Atlantic around day 10, suggesting there are drivers supporting that. However, that signal always seems to be over-riden. @Tamara and others have suggested the warm sea surface temps in West Atlantic, giving a strong temperature gradiant, hence powering the jet out of Newfoundland and towards us, as a significant factor amougst others.

To be fair the model runs for this week and again for next week have had the 25c + runs in the minority of the ensemble runs. In that sense, the models have delivered this week. They just have not delivered the lower probability possibility many of us might well prefer.

Shallow mist and thick dew on all the fields around here on my early morning walk today. Was very nice, with a noticable increasing cool feel in every little dip. I'm not a fan of the descent into autumn (as I have SAD), but misty mornings are lovely!!

Excellent video! Nice week upcoming. Not without complications (low cloud to burn off, always worse to NW, Friday night breakdown and low chance plume for SE early next week). But overall a high pressure anomaly. No strong signal for beyond and for start of September, so still up for grabs.

Still over the other side of the Pennines in North Yorkshire. Weather was awful upto Saturday. However, 3 dry days since with plenty of sunshine. Bit cool and breezy at times, but very pleasant useable weather. Wednesday and Thursday looking fine too. The way this summer has been since the start of July, that has to be seen as a good spell. Hope you’ve had some sun back over in the NW too.

A new chart to me a few weeks back. It was well explained on one of the Met office deep dives back in July (and by @mushymanrob above!). They are great for the really general pattern and showing where uncertainty increases (as mentioned above). They also show how much mobility there is. If as you work down the diagram the lows or high are vertical there is little movement, I.e expect a meridional blocked pattern with “stuck” patterns, e.g. high over UK (at 0 degrees - the middle of the diagram) in early June and low in July. Around recent days the vertical columns become diagonal. The lows and highs are moving W->E, albeit slowly. A steeper diagonal would show zonal (not seen that yet since watching them in June), and a reversed diagonal, represents “retrogression”, movement E->W, which has been seen a bit recently. Also it is possible to count either the number of highs or lows across the diagram at any one point in time. There were 5 in mid July (5 wave pattern - really stuck). Currently there is progression W->E as mentioned above and also a 4 wave pattern). The upcoming H pressure at 0 degrees is shown and then low to West and high to East. Hence some suggesting a 2nd plume might follow the one later this week. As uncertainty increases through time there seems to be a move to a 5 wave pattern and “columns” again. If so, and if there is a high over us, we might have a settled, warm end to August. If the pattern sets up with the high to our Near East, heat and plumes and instability more likely. Given the uncertainty can’t rule out the low pressure in the Atlantic being closer unfortunately. The diagram doesn’t say anything about N->S variation, so clearly doesn’t give a full picture. But used with the anomalies etc does seem to improve our view of the likely “big picture” situation out to perhaps 3 weeks . Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4900865

A new chart to me a few weeks back. It was well explained on one of the Met office deep dives back in July (and by @mushymanrob above!). They are great for the really general pattern and showing where uncertainty increases (as mentioned above). They also show how much mobility there is. If as you work down the diagram the lows or high are vertical there is little movement, I.e expect a meridional blocked pattern with “stuck” patterns, e.g. high over UK (at 0 degrees - the middle of the diagram) in early June and low in July. Around recent days the vertical columns become diagonal. The lows and highs are moving W->E, albeit slowly. A steeper diagonal would show zonal (not seen that yet since watching them in June), and a reversed diagonal, represents “retrogression”, movement E->W, which has been seen a bit recently. Also it is possible to count either the number of highs or lows across the diagram at any one point in time. There were 5 in mid July (5 wave pattern - really stuck). Currently there is progression W->E as mentioned above and also a 4 wave pattern). The upcoming H pressure at 0 degrees is shown and then low to West and high to East. Hence some suggesting a 2nd plume might follow the one later this week. As uncertainty increases through time there seems to be a move to a 5 wave pattern and “columns” again. If so, and if there is a high over us, we might have a settled, warm end to August. If the pattern sets up with the high to our Near East, heat and plumes and instability more likely. Given the uncertainty can’t rule out the low pressure in the Atlantic being closer unfortunately. The diagram doesn’t say anything about N->S variation, so clearly doesn’t give a full picture. But used with the anomalies etc does seem to improve our view of the likely “big picture” situation out to perhaps 3 weeks .

On holiday near Pickering, Yorkshire this week and next with the family. Rainy or showery spells every day so far with just the hint of sun occasionally. Today heavy rain from dawn, nasty nagging easterly. About as bad as you are going to get in first week August. At least the northerly the next couple of days promises sun in between showers. Convergence zone might set up and make it really wet though.….just think what three days like that, with a bit of modest elevation and 20miles or so from the North Sea, in midwinter might have bought. Would have been buried!! It’s not so much fun with kids, on holiday, in midsummer though!

Solid rain since 9pm Friday, don’t know how many hours that is, but it’s far too long!! …tomorrow looks better

I normally try to find a positive aspect of the weather, but today I’m struggling. 60mm rain in the last 36 hours, forecast for 12 more hours or more, all following a very mixed, cool month…July is the payback for 6 weeks of sun in these parts.

Steady rather than heavy here now. However, given its been raining most of the last 36 hours, flooding in prone places along the Irwell and other South Pennine rivers, would seem likely now. Really is as bad as it gets in mid-summer.