The Miracle of Dunkirk
Light winds and little ships help to evacuate the British Expeditionary Force during the Second World War.
One of the best-known events of the Second World War is the evacuation of the British Expeditionary Force between 26 May and 4 June 1940. As German troops closed in, 338,226 British and allied troops, including those of the French army, were extracted from the piers and beaches of Dunkirk under heavy aerial bombardment from the German Luftwaffe.
The evacuation, codenamed Operation Dynamo, involved a hastily assembled fleet of over 800 ships. Many of the soldiers were evacuated directly onto large naval vessels from the two concrete moles protecting Dunkirk harbour, but these could only accommodate a limited number of vessels and the wide sandy beaches prevented others from getting near enough to embark troops which slowed the pace of the evacuation. As a result from 28 May onwards over 600 small vessels were volunteered, or in some cases pressed into service, to extract as many troops as possible directly from the beaches. These have become known as the Dunkirk ‘little ships’. They included merchant marine boats, fishing boats, pleasure craft, lifeboats and even the Mersey Ferry ‘Royal Daffodil’. These small craft either carried men directly back to England or ferried them out to larger craft waiting offshore. They were manned by a mixture of military and civilian crews and were, for the most part, unarmed.
Even though the ‘little ships’ could approach much nearer the beaches, the men waiting there still had to queue for many hours to be rescued, shoulder or even neck deep in water. The courage displayed by the crews of the ‘little ships’, who had to across the English Channel and operate under continuous aerial attack from the German Luftwaffe has been enshrined in the phrase ‘Dunkirk Spirit’.
How the weather played a crucial role
The man charged with co-ordinating the evacuation from the naval headquarters below Dover Castle was Vice Admiral Bertram Ramsay. Indeed Operation Dynamo took its name from the dynamo room that provided power for the facility. Ramsay was well aware that the weather would play a critical role in deciding how many troops could be evacuated. Despite its relative narrowness, the Channel is an offshore environment and subject to strong winds even when conditions nearer the coasts are calmer.
If weather conditions had prevented the little ships from crossing the Channel the operation would have been almost entirely reliant on lifting troops from the moles at Dunkirk harbour and far fewer could have been rescued. The meteorological information Vice Admiral Bertram Ramsay required to decide whether he could call upon the ‘little ships’ was provided by the forecasting division of the Met Office, known as the Central Forecasting Office (CFO). CFO was evacuated to Dunstable for the duration of the war and led by Chief Forecaster C.K.M Douglas, although many of the staff would have been involved over the course of the evacuation.
How the storm turned around
Records show that the weather during the period of the Dunkirk operations was unusually calm. A storm which was coming from the Atlantic turned northwards up the west coast of Ireland and had much less impact than initially predicted on the seas at the Straits of Dover. This was a major turn of luck for the men waiting on the beaches. The maximum wind recorded throughout the evacuation was force four and on most days it varied between forces one and three. The resulting calm sea conditions enabled even the smallest craft to cross the channel and saved many thousands of lives.
The odds of winds greater than force four in the Dunkirk area in May and June are slightly higher than 2:1 whilst the odds against a wind of force five of above are 19:1. In addition, the easterly wind direction reduced the amount of surf the ships and soldiers had to contend with on the beaches and would have blown smoke from the shell-fire and burning town towards the sea, providing a little cover from aerial attack although it also added to the already significant navigational hazards.
Somewhere among those awaiting evacuation at Dunkirk were meteorological officers who had been working with sound ranging units attached to Survey Regiments. Their task was to determine the direction and distance of enemy gunfire to assist with artillery operations. It is not known which ship they were evacuated on, but the unusually calm weather was certainly in their favour and played a significant part in what was later described by Churchill as the ‘miracle of Dunkirk’.
Nineteen RNLI lifeboats helped the operation
Among the’ little ships’ were nineteen lifeboats of the RNLI – the Royal National Lifeboat Institution. On 30 May 1940, the Ministry of Shipping telephoned the RNLI and asked them to send as many lifeboats as possible, as quickly as possible, to Dover. No other information was given but the RNLI quickly organised for lifeboats from around the south and east coast of England to be made available to the Navy.
The Ramsgate and Margate lifeboat crews were asked directly by their naval-officers-in-charge if they would go to Dunkirk and they said at once that they would. They were given steel helmets, food and cigarettes and left on their dangerous mission. The Ramsgate lifeboat Prudential negotiated the 50-mile passage to Dunkirk with eight small Thames work boats in tow. The passage had hurriedly been swept for mines and both lifeboats battled strong tides and dodged wreckage and enemy fire during their journey. Mercifully the weather was one challenge the crews did not have to face. Coxswain Howard Knight’s crew and the naval personnel managed to get 800 men off the beaches during the first night.
The Margate lifeboat, The Lord Southborough – in tow to a Dutch barge to conserve fuel, and containing Coxswain Edward Parker and his crew of ten – set off for Dunkirk with a flotilla of other craft on the afternoon of Thursday 30 May 1940, a few hours after the Prudential. The crew of the Ramsgate lifeboat kept going for 30 hours, saving hundreds more troops. Between them, these two lifeboat crews saved over 3,400 soldiers. Seventeen other lifeboats from Poole around to Lowestoft, including one newly built lifeboat, had been assembled by the RNLI at Dover. These were crewed by the Navy without RNLI crews and therefore little is known of their activities other than that they saved thousands of lives between them.
Even once they had returned to England, the work of the lifeboat crews didn’t stop. A day after returning to Ramsgate, Prudential was in action again, bringing injured troops ashore from vessels anchored offshore along with other lifeboats such as that at Dover.
Despite being under heavy fire for the whole evacuation, only one lifeboat was lost – the Hythe lifeboat, Viscountess Wakefield. All of the rest returned, some heavily damaged, and were quickly repaired at their lifeboat stations to be returned to service.
Coxswains Howard Knight and Edward Parker were awarded the Distinguished Service Medal for their gallantry and determination, and all crew of the Ramsgate and Margate lifeboats received the RNLI's Thanks on Vellum.
Met Office National Meteorological Library and Archive
The Daily Weather Report (UK) which includes the full period of the Dunkirk evacuation is available from our digital library and archive.