Hi folks. Here is the report on the 12 midday outputs from GFS, UKMO, GEM, NAVGEM and ECM for tonight Friday July 26th 2013.
All models show a thundery area of Low pressure moving North from France over the next 24 hours to affect the more Eastern parts of the UK worst with some torrential rain and possible flooding issues later tomorrow and on Saturday night. Scotland will not see this rain until later tomorrow night. Following on behind all models show a cooler and fresher SW flow with heavy showers in the west and continuing across all areas through the first few days of next week. By midweek warmer air encroaches North towards the UK from France again with the chance of further thundery rain soon after midweek.
GFS then ends the week with further showery conditions as further shallow Low pressure skirts NE along the edge of very warm air off the Continent with the potential for further thundery rain at times late in the week before a cooler but still showery weekend unfolds as winds turn more towards the NW briefly. The latter end of the run tonight suggests further showery weather as a trough remains locked over the UK. Some dry and bright weather will always be around and it will feel warm enough in the sunshine despite temperatures settling close to average.
The GFS Ensembles show a Westerly flow the most dominant feature of the weather over the coming two weeks. There is a warmer phase briefly midweek before generally cooler and more unsettled conditions are shown from then through to the end of the run.
The Jet Stream shows the flow much further South than recently and it shows little sign of moving North again anytime soon, blowing frequently Northeastwards or eastwards across the UK.
UKMO tonight shows a large but shallow trough of Low pressure over the UK and the Eastern Atlantic with warm air still flirting with the East of the UK. Thundery showers look the most likely weather type with some warm sunny intervals in between.
GEM tonight shows a changeable pattern likely with a warmer snap midweek before a spell of thundery rain again looks likely towards the end of the week before high pressure settles down over the UK with a drier and warmer spell developing to start the second week.
NAVGEM too shows a warmer phase around midweek with a further surge of showery rain moving East across the UK to open the new month.
ECM shows the most marked warm up later next week. In fact it becomes hot and very humid and with Low pressure close to the SW by the weekend with thunderstorms becoming widespread across Southern and SE Britain by next weekend. Later in the run cooler air spreads in from the West as the Low to the SW moves NE over Scotland with a sunshine and shower mix then to see us out to the end of the run as pressure falls slack over the UK.
In Summary tonight it looks like after a few days of unsettled and cooler conditions early next week when sunshine, showers and even longer spells of rain are possible the common theme is for there to be a warmer phase lasting two or three days later next week. ECM has the most pronounced version of this event with a vigorous thundery outbreak likely for the South and East should it verify while the other models suggest a more moderate version of this event. Longer term the weather looks like turning cooler and changeable under Westerly winds, at least for a time though there are still some suggestion that High pressure could make a comeback later on into August.
Originally Posted by: GIBBY