GFS, ECM and GEM have all picked up on a very shallow LP and some cooler air sliding down the eastern side of the UK Saturday-Monday, which compared to the 00z runs acts to greatly delay the transfer of HP eastward through the UK.
While this means a cooler day or two - though not by much according to GFS, thanks to plentiful sunshine through that cool air mass - it seems to be beneficial for prolonging the settled spell of weather, provided the sliding feature doesn't drop down too far west, in which case some showers would likely develop this weekend.
Curiously, UKMO and JMA don't buy into that feature at all. Either they're lagging behind, or not being fooled when the other models are.
Longer term, the picture is similar across all the models; 2014's most frequent pattern (as far as I can see and allowing for variations on the theme, with those few weeks in August a glaring exception) emerges yet again, with HP to the E/NE and LP in the mid-Atlantic.
However, the Atlantic looks vigorous this time around, and that could act to flatten the ridge, preventing a Scandi High.
GFS shows this until later in FI, but the jet is positioned so far NW that we just see a sort of gigantic ridge from the Azores extending through the UK and well on into Europe. Then a Scandi High does begin to develop, though it struggles a bit against the active Atlantic flow.
GEM goes mad and flattens everthing to produce unsettled westerlies with LP tracking to the Shetland Isles by day 10. Good thing this model is notorious for giving things too much energy (hence the unreasonable bombing out storms, or super-strong HP cells, overcooked summer plumes, excessively cold blasts of Arctic air in winter... and so on).
ECM doesn't flatten things much at all, instead going for an undercutting LP for day 10. This sort of thing tended to win out during June and July, but now it's early Autumn so the rules are a bit different - keeping an open mind on this one.
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