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Reanalysis and Reforecast of the Jan 31 - Feb 1 1953 North Sea Gale

From January 31 to February 1, 1953, a period of about 36 hours during a weekend, a very strong windstorm occurred over the North Sea basin.

Strong winds are not uncommon in the area, but given the shape of the North Sea, a sustained Northwesterly windstorm can pile up water into the narrower Southern North Sea, and in the extreme, sea level can rise by several meters. This is primarily a result of windstress. On this occasion sustained Northwesterly and Northnorthwesterly surface winds in excess of 50 knots were observed for more than 24 hours over a large portion of the North Sea.

Since the flow trough The Channel is small, the water is basically trapped. The very high water caused a major flood in the low lying coastal areas of East central England and, ‘turning the corner’ in Belgium and The Netherlands. In The Netherlands alone over 1800 people drowned, and tens of thousand of people were displaced. In the UK over 300 people died. Major damage was also reported in Scotland and marine interests of many nations suffered badly with several sunken ships and loss of life.

The economic impact of the flooding was also large in terms of lost housing, dead cattle and land left unusable for growing crops for years to come. The memory of this storm lives on internationally. In 1999, during the Millenium hype, NOAA scientists voted the 1953 gale into the top 15 list (no particular order) of the most significant meteorological events of the century. And now we approach the 50 year remembrance.

At the time, weather forecasts were made by time tested synoptic techniques not involving any of the numerical models which we have come to rely upon increasingly since the 1960s. Worded forecasts were normally issued only for ‘today and tomorrow’, i.e. out to about 24 hours, and distributed by radio, newspaper etc. When warranted the forecast would include a warning for unusual sea level rise valid during the next two (astronomical) high water marks - storm surge forecasts were strictly empirical as well. Sea level rise warnings were sent by telex to various authorities so as to take action. The forecast on this day (which was reasonably accurate) gave the authorities a lead time of at most 18 hours to implement evacuation plans (such as they were), issue warnings, guarding of dikes, emergency sandbagging etc.

With how much more lead time could the 1953 storm have been foreseen, if a modern system for Numerical Weather Prediction had been in place?. While the question seems well posed, the situation is somewhat artificial in that we assume modeling and analysis capabilities typical of the mid 1990s, but an observing system as it was in 1953. Of course many other things have changed since 1953. But we leave such other considerations aside.

For the full article, please download the pdf document that can be found in the links on the right hand side of this text.

De baan van de rampzalige stormdepressie tussen 30 januari en 2 februari 1953 (bron: KNMI-bijdrage tot het rapport van de Deltacommissie)
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