Risk of disruption from rain/wind Sunday night/Monday morning
A relatively quiet day today although a further band of rain will cross the region this evening. Tomorrow a rather windy day with blustery showers, some of which could be heavy, especially in the morning.
Now on to the main development for Sunday night and Monday morning. Although the track and intensity of the low pressure centre bringing the event are relatively clear cut now, there is still some fine detail to nail down. Hence what follows is the best prediction based on the latest forecast data.
- Rain will be the initial issue, spreading northwards into our region late Sunday evening, perhaps not reaching Lancashire/Cumbria until after midnight. The wettest period currently looks like being roughly 0300 to 0900 Monday morning and the latest forecast suggests that the largest rainfall totals could occur over Lancashire, Merseyside, Greater Manchester and Cheshire. This morning’s Flood Guidance Statement is expected to have all our region at Yellow (low) flood risk for Monday with a risk of some impacts resulting from surface water excess and perhaps also raised river levels.
- Winds – with the centre of low likely to pass very close to the Northwest winds are not expected to be problematic initially, even when the rain is at its height. The main issue as regards wind looks like being as the low pressure centre starts to pull away to the northeast during Monday morning. As this happens there is a likely to be a sharp increase in wind speeds (W to NW direction), especially across the more southern parts of the region, Cumbria again looking like it will escape the worst of the winds. The key issue is of course what speeds are we likely to attain. For the moment the advice is to go along with the values quoted yesterday i.e. 50-60mph with a low probability of touching 70mph. The most probable time for the strongest winds to be realised looks like being in the 0600 to 1200 time slot. By tomorrow we may be able to narrow that down further. Hence, as Monday morning proceeds there may well be combined impacts from rain and wind to deal with but how the balance between the two will play out is not yet clear. From Monday lunchtime onwards the picture gradually improves, still further blustery showers to come and still windy with gales likely along the coasts but with the risk of the more damaging gusts having receded.
That’s the picture at present, the Severe Weather warnings should have been updated on the Met Office website by around midday so my advice is to check it later today. If you need further clarification on any of the above please refer to our 24-hour response centre in Exeter on the usual number.
A full update briefing will be issued tomorrow morning, in the meantime have a good day,
Alan Goodman; Met Office Advisor (Civil Contingencies)