Our colleagues latest advice from the Met office - hopefully not reaching up to Cumbria...
'Picking up from where I left off on Friday, we close out summer 2020 with a distinctly autumnal week. Two areas of low pressure are set to make their mark over the coming days, the first a deep centre set to track right across the UK tomorrow, threatening disruptive wind and rain to the extent that it has already been named Storm ‘Francis’ by the Met Office. The second centre, somewhat shallower and more uncertain in its eventual track, will bring further rain in during the Thu/Fri period before things eventually start to settle down over the course of the bank holiday weekend. Today’s message will major on the first event, Storm ‘Francis’.
Weather sequence:
The rain will be the first element to play its hand, spreading steadily NE’wards across our region during the early hours of tomorrow. The weather system has some tropical air entrained within it so no surprise some of the rain will be on the heavy side. The initial thrust of rain will be clearing up from the southwest during tomorrow morning but will leave behind a residue of intermittent lighter rain ahead of what looks likely to be a second pulse of heavier rain feeding back into parts of Lancashire, Merseyside, GM and Cheshire during the afternoon and evening, some of this perhaps lingering into the early hours of Wednesday before finally pulling away later tomorrow night.
The winds are not expected to become a major player until later tomorrow afternoon and, more particularly, tomorrow evening. The exact track of the low centre will be key as the strongest winds will be encountered just to the SW of the centre. The risk of wind disruption looks highest across the S half of the region i.e. Cheshire, Merseyside in particular and perhaps also GM. Tomorrow evening and for a while overnight will be the period to watch when, allied to the second batch of rainfall, conditions could become particularly adverse on the roads/motorways for a time.
By Wednesday morning things will be quietening down from both a wind and rain sense with potentially a very pleasant second half of the day ensuing as ‘Francis’ hurries off across the North Sea into Denmark and N Europe.
Severe weather warnings:
Two yellow warnings have been issued in relation to ‘Francis’, one for rain and one for the winds. Both are attached above for your reference.
Rain – valid from midnight tonight to 06:00 Wednesday covering all of the Northwest away from Cheshire. Impact assessment – medium likelihood of low.
Wind – valid from 0900 Tuesday to 0900 Wednesday and covering Cheshire, Merseyside, Greater Manchester and the southern two thirds of Lancashire. Impact assessment – low likelihood of medium. This impact assessment allows for potential escalation to amber closer to the event although it should be added that the likelihood of any escalation is more focussed on Wales and Cent/S England than on the N of England.
Impacts:
Both warnings include full listings of ‘What to expect’. Please use these as best guidance. In the rainfall department surface water excess on the roads and rails could trigger localised transport disruption both during tomorrow morning’s ‘rush’ hour (if rush is still an appropriate word in the Covid era) and perhaps again tomorrow evening. As for the winds the strongest gusts should occur after the evening commute when traffic flows are relatively low. It would be no surprise to see some trees brought down and possibly some localised rural power disruption. The coastal stretch from say Southport down to The Wirral looks to be at greatest risk of disruptive gusts. The warning suggests speeds of 55-60mph possible – these are pretty unusual for August but then again this is 2020 and the meteorological mood swings this year have been amongst the most acute I can recall. Any camp sites across Merseyside, Cheshire, W Lancs and GM are advised to secure well ahead of tomorrow evening. One plus point – the astronomical tides are now tailing off quickly so little or no coastal impacts this time round.
Flood Guidance Statement:
I have included this morning’s Flood Guidance Statement along with the severe weather warnings. The FGS depicts a medium likelihood of minor flooding impacts across much of the region tomorrow and Wednesday, the risk primarily the result of surface water issues. However, note also the low likelihood of some minor river-based impacts for the whole of the region.
Beyond ‘Francis’:
The period of respite between ‘Francis’ and the next low centre will be disappointingly short. Current expectations have much of the Northwest experiencing renewed showers or some longer spells of rain through the course of Thursday, eventually pulling way during Friday to allow a cool, autumnal N’ly wind to settle in for later Friday and Saturday. This is the start of a trend towards an improving Bank Holiday weekend but with cool air in residence by this times and the nights slowly lengthening we could be in for some decidedly cool starts come Sunday/Monday.
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