Good evening. Here is tonight's look at the outputs issued at midday of GFS, UKMO, GEM, NAVGEM and ECM for today Monday July 15th 2013.
All models continue to project a prolonged period of fine and dry weather still to come with very warm or hot and sunny conditions across Southern Britain extending further North across Scotland too later in the week. The few exceptions as mentioned in earlier reports remain, and they are sea fog and low cloud in Western Coastal areas early in the period and maybe in Eastern coastal areas later in the week as winds shift Easterly in response to the Northward movement of High pressure to Scotland. The weekend too looks like being another hot and sunny one nationwide with light Easterly winds and little if any cloud.
GFS then shows next week as a week when slow changes begin to take place as pressure begins to fall somewhat though it will be late in the week or weekend before any noteworthy changes look likely to affect anywhere away from the South where a few thundery showers will push up from the continent at the same time as Low pressure slips in from the NW with rain and cooler air slipping in from off the Atlantic. The run ends with a cooler Atlantic set up with Low pressure to the North with fronts crossing East bringing rain and then showery weather to all parts.
The GFS Ensembles show a continuing trend towards cooler air moving in from the NW late in the period with rain at times and rather cooler conditions. However, the ensemble mean still shows a group of members averaging conditions still set quite fair and warm in the South late in the run.
The Jet Stream shows the flow harmlessly blowing across very far Northern sea waters before it gently descends South towards the UK at the very end of tonight's output.
UKMO shows High pressure centred over the Shetland Islands by Sunday with a ridge still lying South from its core down across the UK maintaining fine, sunny, very warm and settled weather for all though the odd thundery shower may well be grazing the far SW by Sunday night should it verify.
GEM tonight shows pressure slowly leaking away early next week as the High moves further away to the NE. Low pressure will be closing in from both the South and NW with the risk of some thundery showers as well as Atlantic rainfall approaching the NW later with attendant cooler and fresher air for 10 days time on.
NAVGEM tonight too pushes High pressure further away to the North through the start of next week with the risk of showers, some thundery increasing as we move deeper into next week.
ECM tonight shows a slow deterioration in conditions next week but not necessarily in temperature terms. It looks like pressure will fall slack as the High pressure over the UK becomes more ill defined with light winds and maintained high temperatures creating more instability aloft with an increase in the risk of thundery showers developing across the UK as we move through the week.
In Summary changes in the weather remain slow with little or no change at all expected within the next 7 days with the far North joining in with the very warm and sunny conditions too beyond midweek. Next week sees slowly falling pressure with several scenarios playing out for position between the models. There has been a slight shift towards the risk of a more thundery phase in conditions as we move through next week prior to the Atlantic moving back in towards the UK late in the extended outputs tonight. Nevertheless, there is little to concern those wanting to see maintained fine and settled weather. Any major shift toward anything significantly cooler is still only shown in output between 10-14 days away and the partial deterioration in synoptic pressure patterns shown by mid term output next week would likely only result in scattered heavy and thundery showers with many places seeing the balance maintained to bias fine and warm conditions continuing for some while longer.
Originally Posted by: GIBBY