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| Near the Hamble mouth at high tide, 3rd January |
2nd January 2018, the early hours: the first of two full moons this month. This one informally known as the Wolf Moon. It was a also a "supermoon", being full at perigee (its closest point to the Earth in its orbit around the Earth). Though the ensuing spring tides around Britain weren't forecast to be as high of some of those we have seen in recent years, they were raised through a combination of low atmospheric pressure and strong ( sometimes gale force) onshore winds. They came as a succession of low pressure systems crossed the British Isles; the jetstream being over the British Isles in the first week of January. One of these lows was so-called Storm Eleanor (but all the Eleanors I know aren't at all stormy) which passed over the British Isles on Wednesday 3rd January. It had a central pressure of 966 millibars at one point, centred over southern Scotland / the far north of England. Tidal surges of around 30cm above the astronomical forecast heights along the south coast on Wednesday and about 46cm on Thursday. These took the height of first high water at Southampton and Warsash to 5.14m on Wednesday and 5.24m on Thursday; triggering the EA to issue a flood alert.
On Tuesday evening and Wednesday morning, there were more than sixty flood warnings and well over a hundred flood alerts. Some of them included river (fluvial) flooding because of rivers rising in response to the rain since Boxing Day (mostly East Anglia and the Midlands). Most of them, though were coastal and estuary; mainly western and southern coasts of England. There were warnings along the tidal Wye and Severn; though as there were no severe flood warnings here, it didn't sound as bad as it did during the high spring tides / tidal flooding this time four years ago. Over the course of Wednesday, the flood count went down; but Storm Eleanor also affected western continental Europe particularly France and Germany. In France, the Vigicrues river map was turning yellow with touches of orange as rivers rose after heavy rain and (in mountainous areas snow); and, as on this side of the Channel, the effect of strong winds and high tides along the Channel and Atlantic coasts. There were flood alerts along all the major rivers and their tributaries - plus ca change (see notes last month mentioning the Loire stuck at estival levels). There was a vigilance orange along the Lower Seine because of a triple whammy of strong winds generating waves; high tides; and the high volume of water flowing downstream, thanks to most of its main tributaries running high for sometime. By Friday evening, the flow through Paris had reached 1000 cubic metres per second (over 1100 cumecs on Monday 8th). Even after the tides waned and the weather became drier from the following weekend (6th / 7th) the larger rivers were still rising as the heightened flows from the tributaries propagated downstream. At Saumur, the Loire was forecast to peak at around 3000 cumecs on Tuesday 9th January (a month earlier it had only just made it to 200 cumecs).
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| Flooded path and bank erosion near the Hamble mouth |
On the Wednesday - windy but sunny after several days of rain during the middle of the day - I went down to Warsash. It was very windy, but bright along the shore. Southampton Water was very choppy and tide was rising on the foreshore, with about 45 minutes to go before first high water. The waves were about 50cm high and much smaller than they would have been in the open sea. I was able to walk along the shore; the backshore widening heading towards the Hamble.
The trouble came, though when I tried walking up the Hamble from the shore (see photos above). The path along the raised bank was flooding as waves splashed over the low wall separating it from the Hamble. It was also flooding beneath the bank, at the far end of the lagoon. I tried both, but didn't get far. I got as far as the gate; clambered over it and clamber back over it again; going any further clearly a lost cause. With the tide remaining high through the middle of the day (HW2 14:05h), I had no choice but to walk back along the shore to the path up to Cowes Lane; then double back along Hook Park Road to get to Warsash and the Quay. I got to the quay about half-twelve; about an hour after HW1. Though no water in the quay car park now, it was clear from the seaweed debris that it had been. By now, the path up the Hamble past the Pink Ferry was walkable; but had large puddles which had been there for a while because of the rain. They were there when we'd walked this way New Year's Day afternoon.
On the Thursday, the tide was even higher. I didn't go down there; but over the next few days numerous photos and videos appeared on Facebook with flooding on both sides of the Hamble, all along it, including Warsash, the Bunny Meadows path, the shore at Lower Swanwick. On the west side, it had spilled along the road behind Hamble Quay (a few motorists unwisely trying to negociate it). Among the footage on the Warsash side was a video posted by Warsash Harbour Master. This showed water spilling both into the car park (a number of cars and vans parked there - time they put up signs warning people) and into the sailing club / marina nextdoor; though unlike cars, boats float. This was the highest tide in this suite of spring tides; and probably one of the highest since 2014.
The tidal cycle subsequently waned with the moon, with drier and much colder weather coming in over the weekend 6th / 7th January.
Flood warnings - https://flood-warning-information.service.gov.uk/warnings
On the Thursday, the tide was even higher. I didn't go down there; but over the next few days numerous photos and videos appeared on Facebook with flooding on both sides of the Hamble, all along it, including Warsash, the Bunny Meadows path, the shore at Lower Swanwick. On the west side, it had spilled along the road behind Hamble Quay (a few motorists unwisely trying to negociate it). Among the footage on the Warsash side was a video posted by Warsash Harbour Master. This showed water spilling both into the car park (a number of cars and vans parked there - time they put up signs warning people) and into the sailing club / marina nextdoor; though unlike cars, boats float. This was the highest tide in this suite of spring tides; and probably one of the highest since 2014.
The tidal cycle subsequently waned with the moon, with drier and much colder weather coming in over the weekend 6th / 7th January.
Links / sources of information:
UK Met. Office - https://www.metoffice.gov.uk/
Environment Agency (England):
Flood warnings - https://flood-warning-information.service.gov.uk/warnings
France
Vigicrues (flood warnings, links to gauging stations with real-time river levels and flows: https://www.vigicrues.gouv.fr/
