Good morning. Here is the latest report on the 12 midnight outputs of GFS, UKMO, GEM, NAVGEM and ECM for today Saturday December 14th 2013.
All models show troughs of low pressure crossing East across the UK later today and tonight in a strong SW flow. The rain will be heaviest in the NW and here will be coupled with severe gale force winds for a time. Clearer air behind the fronts will bring a quieter spell overnight before tomorrow sees a re-run of today as another swipe from Atlantic fronts affect all areas in a mild weekend and a stormy one over the NW. Early next week sees somewhat less mild conditions for a ttimes as pressure builds near the South with later Monday and tuesday becoming dry and bright. By Wednesday the next powerful Atlantic storm will of wound itself up to the NW with troughs swinging East with wind and rain for all by the end of the day.
GFS then shows a sustained period of Atlantic dominated weather with very deep low pressure to the North pushing active troughs and secondary Lows NE across all areas with spells of rain followed by sunshine and squally showers, wintry at times over the hills in the North. there sheems little chance of sustained cold weather with a white Christmas unlikely away from higher Northern elevations. The end of the run leading out of christmas and towards the New Year looks unlikely at this stage to see any major pattern change from the generally wet and windy conditions in SW or west winds though it might turn rather colder from the NW.
UKMO shows a blustery west wind behind a cold front next friday with a mix of sunshine and showers, wintry on Northern hills briefly before it looks like milder weather will return over the weekend as a new Atlantic syatem bears down on the UK from the West.
GEM shows a mild and windy spell of weather following a briefly chillier showery period late next week. Winds will be gale force and with fronts straddling the UK there would be rain at times for all, always heaviest across the North with some drier and very mild periods in the SE.
NAVGEM also shows a milder period next weekend as the cool and showery weather late next week becomes replaced by gale SW winds and warm frontal activity bringing rain NE across all areas next weekend.
ECM maintains very unsettled weather with the potential for a viscious storm system crossing the UK next weekend with storm force winds for a time and heavy rain followed by a mild SW flow with rain at times in the north and West and still windy weather everywhere.
The GFS Ensembles show a very unsettled and windy spell over the coming two weeks with a domination of Low pressure over or just to the North of the UK. After a mild start temperatures will moderate to average and perhaps slightly below average later with wintry precipitation developing over the hills at times.
The Jet Stream continues to show a sine wave pattern in a very strong flow near the UK for the next week or so. there are still indications this morning that the flow may sink South of the UK in week 2 increasing the risk of colder conditions over the UK later.
In Summary there seems little change in the overall windy and changeable theme of the weather over the entire period. the only main difference or trend seems to be that the South could become quite close to high pressure again over Europe for a time later next week decreasing the effects of rain and wind here and making it become quite mild again before it seems that it may well become wet and potentially stormy again over christmas week when Northern high ground could see some snow. Overall though the chances of a whte Christmas remain quite slim though with Polar maritime air present close by a few may have a surprise.
Martin G
Kilmersdon Radstock Bath Somerset