UK meteorology

Malcolm's thoughts for the 19th:
The weekend will be warm and sunny with some exceptions.

Today after a chilly start it will warm up quickly with plenty of sunshine. It may be a little filtered still in north west Scotland where the front is still adjacent and low cloud and mist will still be a feature along the south east coasts so temps down here. As they will be a tad in other coastal areas as the sea breeze kicks in. The low cloud and mist may become more extensive through the evening and overnight which again will be quite cool under clear skies. But by 00 Sunday cloud and rain with a freshening wind will encroach N. Ireland and western Scotland as fronts associated with the low over Iceland track east.

Through Sunday the front tracks a little further south east thus continuing patchy rain with cooler temps and quite breezy in the north west whilst elsewhere the ridge continues to dominate and another warm and sunny day will unfold with the same caveat vis low cloud in the east and sea breezes.

Monday will be another very warm and sunny day for most, the exception being the west of N. Ireland and the Western Isles where the front is still loitering. But changes are afoot to the west. Another cut off upper low has formed west of Iberia, courtesy of renewed ridging north east of the Atlantic high pressure, which invigorates the low pressure to the south which moves north introducing an easterly and perhaps some convective the south as the ridge is pushed north east.

By Tuesday this has resulted in a high cell north of the UK and with the aforementioned low pressure safely ensconced to the south there is a light easterly over the UK leading to another very warm day, apart from the north of Scotland where the front is still lingering. Still a risk of some thundery outbreaks over central England and Wales.

A not dissimilar story on Wednesday except the high pressure has shifted north east over Scandinavia albeit still maintaining the easterly over the UK and still the possibility of convective activity in the south in what will be another warm and sunny day for everyone.

According to the gfs around now is rather a key time as the upper trough to the south gets a further boost which tends to establish an anticyclonic/low pressure north south split but which will prevail?

Malcolm's thoughts for the 20th:

Fine, warm, and dry but there are exceptions

Currently a band of light rain is across N. Ireland and central Scotland which will not progress much further south east against the block during the day. On the contrary it will move back the way a tad this evening and over night resulting in a substantial accumulation over the western Isles. Elsewhere it's been a clear night apart from the east and south east coasts where low cloud pushed a little inland. also some patchy mist/fog along the south coast. This will generally clear during the day So another very warm day beckons for but cooler where the sea breeze in. The gfs temps are probably under cooked but it does give an idea of the range.

So tomorrow continuing wet over the north west although it may slowly clear later and once the low cloud has cleared the east anther very warm day with the chance of thundery showers developing in central/southern areas, and the usual caveat vis sea breezes and of course across N. Ireland and the north west of Scotland where the front and rain severely depresses the temps.

But a key move on Monday vis the overall evolution is the high pressure once again amplifying north east creating another cut off low that slips south east towards the low pressure in the western Mediterranean

On Tuesday the result of all of this sees a new surface high cell north of Scotland with a broad area of low pressure to the south thus an easterly regime over the UK which will bring cooler temps the east coast and perhaps some mist/low cloud whilst elsewhere will have another warm and sunny day with a continuing risk of thunderstorms in southern areas.

A very similar story over the next two days as the high cell relocates over Scandinavia and the area of low pressure persists to the south with the continuing risk of thundery outbreaks in the south and west

Malcolm's thoughts on the 21st:
Today marks the transition to the next phase of this fine spell of weather (not forgetting that this hasn't, and isn't the case, in N. Ireland and north west Scotland). as the amplifying north east of the Atlantic ridge disrupts the main trough and forges a corridor to the Scandinavian high pressure. This essentially sets the pattern for the next few days and through the holiday weekend with high pressure to the north and north east dominating proceedings and with an unstable low pressure area to the south an easterly regime over the UK is set in motion with the Atlantic trough relegated to the west by the aforementioned corridor.

The detail for the next few days.

Today - The front and band of rain is still affecting N. Ireland ans western Scotland and will continue to do so through the day and evening with some heavy pulses traveling along it whilst elsewhere after a clear night another warm, very warm, day beckons once fog and low cloud has receded from eastern coastal areas although it will still be a tad cooler here. But cloud will bubble up in central southern and western areas that could lead to isolated thunderstorms.

By Tuesday there is a new high cell north of Scotland where the decaying front is still lingering albeit the rain has died out but temps around the region remain depressed Elsewhere Another very warm sunny day with again the chance of thunderstorms in the south. The usual caveat vis temps along coasts, particularly the east coast with the onshore wind.

By Wednesday the center of the high has shifted northeast and whilst warm and sunny conditions continue to dominate in many areas with again the risk of thundery outbreaks, temps in northern Scotland and eastern coastal areas decidedly cooler in comparison.

On Thursday the aforementioned 'corridor' to the west is in full swing and with the low pressure to the south pushing north a trough does likewise bringing more concentrated convective outbreaks to the south and west in the freshening easterly wind.

A similar story on Friday vis the risk of thundery outbreaks in the south and again another warm day but with a definite westerly bias and cooler in the eastern half of the country with possible some low cloud and mist along the coast.

The rainfall distribution reflects the above - hopefuly

Malcolm's post for the 22nd:
The rain that has been plaguing north west Scotland will finally peter out today but still leaving a legacy of cloud which will gradually thin out from the south west. But low cloud and mist over eastern Scotland will persist, and even own as far as north east England, and this will depress the temp in these areas whilst further south it will generally be another, warm, sunny day which again could trigger some downpours.

Overnight the low cloud and fog will become quite extensive over the eastern part of the country but clearing quickly in the morning but still much cooler along eastern coastal areas in the on shore breeze whilst elsewhere should be another warm and sunny day, albeit still the possibility of the rogue shower. Out to the west south of Iceland an active front sits thanks to temporary foray from the upper trough to disrupt the SW/NE high pressure 'corridor'

I say temporary foray because by Thursday high pressure is once more surging north east west of Ireland whilst whilst a trough in the low pressure to the south pushes north bringing rain to the south, perhaps some convective outbreaks embedded? and at the same time initiating a quite brisk easterly over the southern half of the country. So still quite warm but again cooler along eastern coasts.

The band of rain/showers continues to push north overnight and through Friday whilst the high cell to the west moves north east, all of which accomplishes two things. A variable temp spread over England and Wales and of course the east coast as the brisk easterlies have spread themselves further north

The trough continues north through saturday but is of little consequence by now whilst the high cell is now west of southern Norway (the alignment of this over the next couple of days is quite important) whilst down south the low pressure is pushing north along with some convective activity which could well bring some heavy thundery outbreaks to the south and west. This scenario introduces quite a spread of temps across the whole of the country but the jockeying for position of the main players High to the NE and low pressure to the SW) has introduced warmer air into the for south.

Malcolm on the 23rd:
As we move through the end of the week and into the holiday weekend an overall summary of dry, warm/hot and sunny would not be out of order but must come with a couple of caveats relating to the specifics of the daily analysis. They are the regional temp variations and range and intensity of any convective activity, whether home grown or imported from the continent

Today. It has been a clear night for most but the low cloud.mist eastern Scotland and the north east yesterday did spread further south and inland by this morning. This will burn back as the sun rises but will still affect NE/E coastal regions throughout the day so whilst elsewhere will experience another warm and sunny day temps in these regions will be depressed. Again there may be a few showers bubbling up in the south east this afternoon and late in the evening a more concentrated batch will arrive from the south east.

The concentrated band of showers associated with the trough will continue to track NW across southern England into Wales through Thursday and some of these will be heavy with the odd thunderstorm So although another warm day is on the cards a fair temp variation denoting the specific analysis as be seen on the temp chart.

A quick look at the general pattern on Friday finds the Azores> Scandinavia corridor and the cut off upper Iberian low in good working order.

and specifically the high cell is creeping NE to the NW of Ireland and the trough north over England and wales producing sporadic heavy bursts of rain all of which, on a basically warm day, does again produce some marked regional temp variations

By 1200 Saturday the high is north of Scotland and with low pressure pushing north the gradient tightens resulting in the easterly winds increasing a tad and thus on another warm day, warmer air has now arrived in the south,eastern regions will again be adversely affected temperature wise. Still a chance of the odd shower in the south.

Sunday a generally warmer day with the usual east coast caveat and elsewhere if sea breezes kick in, and a chance of thundery outbreaks in the south

Malcolm's thoughts:
For this period the UK will essentially stay withing the circulation of the low pressure to the SW/S and thus a moist, unstable, airstream from an easterly quadrant. Temps remaining above average but cooler in the east with a fair amount of sunshine with a westerly bias but but showers and storms, sometime in concentrated bands, will affect many areas at times.


After a generally mild night the low cloud and mist affecting many areas will gradually retreat to the eastern coasts (hopefully) leaving a sunny but a tad cooler day than of late, But storms currently over Holland will swing west along the south during the day with possible some intense localized rainfall if you are unlucky to catch one. This evening the low cloud and mist will start to return inland as another band of showers starts tracking north east across the SE and the North Sea.

The murk may well hang around a bit in eastern regions as the line of showers and the odd storm cross eastern and central areas during another warm day so sporadic sunshine unless you in western areas, particularly western Scotland.

By Thursday the next phase in the evolution is underway with the cut off upper low to our south west boosting and re-orientating the surface low which will increase shower activity in general, with the odd storm, but may also negate the east coast malaise on another warm day.

On Friday the slack area of low pressure covers the UK with again a fair bit of showery activity whilst out to the west the Azores high is ridging north quite strongly between the cut off lows.

Not a lot of change on Saturday but the high pressure transition continues apace with, something I've touched on previously, a strong westerly jet in the tight thermal gradient north of the high pressure.