History’s Most Critical Forecast

Pressure — the new film dramatising the most critical weather forecast in modern history, in Australian cinemas from 29 October 2026. Credit: Wikipedia

This feature article originally appeared in AFLOAT Magazine and is the latest edition of Weather with Kevin Green* exploring the history of marine weather forecasting, storm tracking and the science that changed the course of history.

The movie, based on the book Pressure by David Haig, will be released in Australian cinemas on Thursday, October 29, 2026. Much like the classic 1962 film, The Longest Day, it re-enacts the role meteorologists played. It dramatises the friction between the British and American weather teams in deciding on that fateful day – 6 June 1944. Scottish meteorologist James Stagg, backed by real-time data from his extensive network of weather stations, won the day by persuading supreme allied commander general Dwight D. Eisenhower to shift the landings from the 5th to 6th June. This was despite strong lobbying from American counterpart Colonel Irving P. Krick. His synopsis relied more on “analog forecasting”, based on historical pattern readings that showed calm weather from previous forecasts for that part of the English Channel for several years.

The movie Pressure dramatises the real life conflict between these two meteorologists, pitting the “dour but canny Scot” Stagg against the bombastic Krick, while the abrasive Eisenhower, interrogated both. The abrasive scene in Pressure between Stagg, who feared for his wife’s safety at that very moment and the aggressive Eisenhower is compellingly acted by Andrew Scott and Brendan Fraser respectively. Given that most Channel weather comes from the Atlantic, a critical part of Stagg’s information came from weather stations to the west and the furthest in that direction was Ireland. Here, at 13:00 on 3 June, 21-year-old Maureen Flavin Sweeney became first to forecast a severe storm approaching Europe across the Atlantic Ocean. Despite the official neutrality of Ireland during World War Two, information gathered by the Irish Meteorological Service was shared with the Allies. Mrs Sweeney received a phone call from Stagg’s office asking for the readings to be checked again. She re-ran the tests and confirmed her results. Further analysis by Stagg’s team further showed that there would be break in the weather just after this front, on 6th June; as did indeed happen. Pressure, both in terms of air and human, was critical in lobbying for the date of 5-6 June because the next time with suitable tides was 18-20 June; which turned out to be stormy.

James Stagg received numerous honours for his efforts, including being appointed an Officer of the US Legion of Merit in October 1945. He later worked as director of services at the Meteorological Office (‘the Met Office’) until 1960. James Stagg died in 1975 and was buried in Dalkeith, near Edinburgh. On 6 June 2019, 75 years to the day since D-Day, he had a plaque unveiled to him in Dalkeith. The movie Pressure‘s closing credits state that the invasion’s success enabled the Allies to defeat Germany within a year. Eisenhower, in a 1961 conversation with John F. Kennedy, credits Overlord’s success to the fact that the Allies “had better meteorologists than the Germans”.

*Our resident weather expert Malcolm Riley is taking a break from reading the skies – hopefully enjoying a few fair winds of his own. He’ll be back in a couple months.

This feature article originally appeared in AFLOAT Magazine. To explore more stories like this, browse the AFLOAT Magazine archive or view the latest edition of AFLOAT Magazine.