We wanted to let you know about the possibility of flooding this weekend. We are sharing very early, so there is a chance that the forecast could yet change and updates will be sent as needed.
Successive bands of rain will pass over Sussex on Friday, Saturday and Sunday before clearing up on Monday.
Friday (29/10/2021): 4 to 15mm
Saturday (30/10/2021): 7 to 27mm
Sunday (31/10/2021): 17 to 30mm
The flood risk will be influenced by the cumulative rainfall amounts and its location, over the three days which is hard to tell accurately so long in advance. As context, two bands of rain on Wednesday last week brought around 40 to 50mm of rain to most places in Sussex which resulted in widespread flood alerts and 5 flood warnings being issued.
If the weather forecast doesn’t change over the next few days, we feel we are likely to issue a similar amount of messages this Sunday as we did last week; Flood Alerts widely across Sussex, and some Flood Warnings (~5) to indicate where flooding to property is expected. It is currently difficult to predict exactly where we might issue Flood Warnings, but it is probable to be the predominantly smaller catchments with small numbers of isolated properties. For planning purposes we are also provided a less likely scenario by the Met Office termed the ‘Reasonable Worst Case’. This less likely scenario suggests on Sunday we could measure 30 to 50mm of rain which would see more Flood Warnings being required.
Surface water flooding impacts could be experienced where the rainfall is heaviest.
Breezy conditions will generate moderate waves and the chance of small amounts of spray along the coast, but with tides low and currently falling to neaps, coastal flood risk is low. We are not expecting to issue any coastal Flood Alerts or Flood Warnings. However, the Reasonable Worst Case scenario also suggests there could be very strong winds and very large waves Saturday. With the possibility of a small number of coastal Flood Alerts. However, the low tides should still keep coastal flood risk to a minimum.
We are organising additional staff to be available to assist our response at the weekend. We will continue to operate our assets to reduce flood risk as much as possible.
We will share another message on Friday (or before if needed), to keep you informed of how the forecast is looking.
If anyone has any questions, please do ask.
The Environment Agency
Flood Warning Duty Officer, Sussex