BUSHY PARK’S WAR HISTORIAN TELLS THE INSIDE STORY OF THE D-DAY WEATHER MOVIE
BY DAVID IVISON
(TEDDINGTON-BASED ARCHIVIST FOR THE FRIENDS OF BUSHY AND HOME PARK AND THE ROYAL PARKS)
The film ‘Pressure’ starring Andrew Scott (as James Stagg) and Brendan Fraser (as General Eisenhower), is showing at the cinemas in Kingston amid a lot of publicity.
This is based on the true story of the pressure the weather forecasting team were under on the final days leading up to D-Day in June 1944.
For those who have seen the film, you may have noticed the reference to Bushy Park within the first few minutes of the start.
Why mention Bushy Park, and how does it fit into the D-Day story?
Unfortunately, there is no explanation given in the film.
To do this we need to go back three months from the time in the film to the beginning of March 1944, with the establishment of the Supreme Headquarters Allied Expeditionary Force (SHAEF) in Bushy Park.
This was an organisation headed by General Eisenhower and set up to plan and carry out the invasion of Europe.
It was realised early in the planning for D-Day that weather forecasting would form a critical part of any decision making.
To deal with this, SHAEF set up a small section devoted to personally providing Eisenhower with weather forecasts relating to the invasion of Europe.
James Stagg, of the Met Office, was appointed as its head, with Lt Colonel Donald Yates of the US Air Force as his deputy.
Apart from this position, Yates was also the most senior American weatherman at the USAAF weather centre for the US Strategic Air Forces in Europe (USSTAFE), which was based in Bushy Park.
Throughout the war the allies had set up a comprehensive network of weather stations and sea swell monitors on the US east coast, Canada, Greenland, Iceland and the western approaches to Britain.
All weather data collected by the network was funnelled through three main weather centres; the Met Office in Dunstable (RAF), the Admiralty in London (Navy) and USSTAFE (US Air Force) in Bushy Park.
This information was then discussed daily (from the end of May, three times a day) over scrambler conference telephone calls between the three centres.
Stagg and Yates at SHAEF then agreed on a combined weather forecast.
At the beginning of April 1944, Lt General Beddell Smith, Eisenhower’s Chief of Staff, required Stagg and Yates to present to Eisenhower every Monday a five-day weather forecast for the south of England and the French coast.
Stagg never believed that he could deliver a five-day forecast with certainty.
The British tended to use scientific methods involving upper–air measurements, whereas the Americans used a series of historic data to make their future forecasts.
Inevitably, the individual charts produced very different results.
This led to furious arguments between the British and American teams, especially Irvine Krick, who served on Yates’ staff in USSTAFE, and Sverre Petterssen, a Norwegian attached to the Met Office in Dunstable.
It was the good working relationship between Stagg and Yates which meant they agreed to present the critical five-day forecasts at the end of May and early June 1944, based on scientific readings rather than historical data.
For the rest of the story, I suggest you go and see the film as it begins in Southwick House, SHAEF’s forward headquarters, near Portsmouth.
The film does move some of the facts around for dramatic effect.
In it Krick is shown playing a pivotal role in the presentation of weather charts.
This did not happen; Stagg and Yates were the only ones presenting weather forecasts to Eisenhower. Krick, being on Yates’ staff was based at Bushy Park.
Schematic diagram for 6-way telephonic weather conferences used to prepare five-day weather and wave predictions for Operation Neptune / Overlord during April to July 1944. Note: key participants are listed by given name.
Irvine Krick
Sverre Petterssen
Lt Colonel Yates USAAF
Wing Commander Stagg RAFVR