Did the outcome of World War II depend on the weather? Separating fact from fiction in ‘Pressure’

I remember learning about D-Day, and how crucial the weather was to its success. It was a turning point in World War II, the invasion of Normandy, France, on June 6th, 1944. For months, the American and British forces had been preparing, practicing everything in England before the big day.

A huge amount of work went into deceiving the Germans about the planned invasion. It was initially set for June 5th, but the day before, Royal Air Force meteorologist James Stagg recommended to General Dwight D. Eisenhower that they postpone it until the weather improved.

The new film “Pressure,” directed by Anthony Maras, is based on a relatively obscure historical event. It’s adapted from a play of the same name by David Haig, who also played the lead role and co-wrote the movie’s script with Maras. Haig has described the film as similar in style to “The Imitation Game.”

According to Haig, many unsung heroes only gain recognition when researchers uncover their quiet acts of bravery, which then make for a compelling story. He shared this insight while speaking over Zoom from London.

Review

‘Pressure’ dramatizes World War II’s decisive turn, a clash between generals and weathermen

Brendan Fraser and Andrew Scott deliver compelling performances in this film about the critical preparations leading up to D-Day. The story focuses on a top-secret operation demanding complete dedication – and, surprisingly, a requirement for clear weather.

Shortly after the play first appeared in Edinburgh in May 2014, Haig started working on a script adaptation. The play later transferred to London’s West End in 2018 and premiered in North America in Toronto in 2023. Director Maras joined the project following his 2018 film, “Hotel Mumbai,” which was also based on real events.

Honestly, when I first read the play and the script, I was completely blown away by how one single decision rippled outwards and changed so many lives. It wasn’t just about the soldiers on the beach, but how it affected people across the entire Allied effort. You usually think of war stories focusing on the fighting, but this really showed me all the incredible stuff happening behind the scenes, too.

This movie builds upon Haig’s original play by adding new characters and scenes, notably a depiction of the D-Day invasion itself. The cast includes Andrew Scott as Stagg, Brendan Fraser as Eisenhower, Kerry Condon as Eisenhower’s secretary Kay Summersby, Chris Messina as meteorologist Irving P. Krick, and Damian Lewis as British army officer Bernard Montgomery.

I was really impressed with how much effort Haig and Maras put into making the production historically accurate – they even used actual footage from the war! Haig explained that, like any play or movie, things are naturally dramatized a bit, but at its heart, it’s a very truthful portrayal.

Maras explains they made every effort to be historically accurate and tell the full story, all within the limits of the film’s two-hour length.

Here’s what is true and what is dramatized in “Pressure.”

The importance of the weather

D-Day, officially called Operation Overlord, was carefully planned to coincide with specific conditions like favorable weather, tides, and moonlight. The attack involved forces arriving by sea, air, and land, so clear nighttime visibility and high tides were essential to minimize the distance between the landing boats and German defenses.

As Maras explained, the distance from where the boats landed to the German defenses really varied depending on the tide. At high tide, it was only about 50 meters to reach the dunes and then the bunkers. But when the tide was out, you were looking at a 300-meter scramble across the beach just to get to the cover of the dunes – a huge difference, and a really dangerous situation for anyone landing there. It really makes you think about the challenges the soldiers faced.

A clear forecast with low winds and no rain was essential.

As a movie buff, I always wonder about ‘what ifs,’ but this one’s pretty chilling. Apparently, the boats they used for D-Day were really old and not designed for rough seas. According to Haig, if they’d launched on May 5th, like originally planned, with the storms the meteorologist Stagg predicted, those boats would’ve flipped over. He says it wouldn’t have lost the war, but it definitely would have dragged it out, costing a huge number of extra lives. It’s one thing to see a dramatic storm in a movie, but knowing how close they were to a real disaster? That’s sobering.

For the movie “Pressure,” the filmmakers used authentic weather charts and instruments. The team responsible for the film’s look recreated the iconic D-Day map originally used at Allied headquarters in Southwark House. Interestingly, the original map was created in two parts by different companies to keep its details secret.

I was really struck by the attention to detail in this film. The production designer, Maras, told me they painstakingly recreated even the maps you see onscreen. They went so far as to source the same paper stock from the original mill used eighty years ago! It’s that level of commitment to the smallest details that really elevates the film’s authenticity.

Exercise Tiger

The movie begins by showing Exercise Tiger, a months-long training exercise for Allied soldiers that took place on Slapton Sands in England. Leaders wanted to get the inexperienced troops ready for the realities of combat, exposing them to what they would likely see and hear during battle.

According to Maras, they practiced extensively with a complete mock run of the D-Day invasion to prepare.

Practice exercises held in secret from late 1943 to April 1944 were plagued by mistakes, including soldiers being accidentally killed by their own side. These errors led to the deaths of at least 700 American and British troops.

Despite being a near catastrophe, D-Day is remembered as a major military success, according to Haig.

Maras wanted the film to begin with this moment to emphasize the headspace of the Allied leaders.

Maras asks how to effectively show the real dangers of failure in this story. He explains that when the military leaders are discussing strategy, they fully understand the weight of their decisions because they’ve witnessed the consequences firsthand. The graphic image of bloodshed – young soldiers injured in the water – was deliberately designed to leave a lasting impression on viewers, emphasizing that mistakes by those in charge could lead to similar tragedies.

I’ve always been struck by how much weight Eisenhower carried on D-Day. Apparently, he was so worried about the outcome that he actually wrote two different letters beforehand – one if the invasion went well, and another if it failed. It really shows how much pressure he was under. People say he barely slept, maybe just two hours a night, and was incredibly anxious. It’s amazing to think about the burden he carried.

Stagg vs. Krick

As a film buff, I was really gripped by the scene where Stagg arrives at Southwark House, just four days before D-Day. The tension immediately kicks in because he clashes with Krick, an American weather forecaster. They have completely different views on what’s coming – Krick is optimistic, pointing to past weather patterns and predicting sunshine and calm seas. But Stagg, relying on what he feels are more thorough and modern forecasting techniques, is convinced a huge storm is brewing. It’s a classic setup – two experts at odds, and the fate of an invasion hanging in the balance!

According to Maras, Stagg actually joined the team around November 1943 and arrived at Southwark House a few months before that. While the depiction of the relationships between Stagg, Krick, and the others is correct, the events happened over a shorter period of time than originally portrayed. His transfer wasn’t a matter of days, but months, earlier.

Stagg and Krick each wrote about what happened, and both believed they were correct in their assessment of the weather. While Haig and Maras have created fictionalized accounts of their conversations and disagreements, the underlying conflicts were genuine.

Haig explains that different continents use different weather prediction methods because of their climates. Krick’s forecasting system worked well in the United States, but it’s not effective in the U.K., where the weather changes so rapidly – often within just five minutes.

Maras explained that they decided to proceed, believing the weather would cooperate. However, this decision sparked a heated and intense argument between him and the rest of the group.

In the movie, Krick insists he’s always accurately forecast the weather before battles, pointing to his track record in North Africa as proof. And, strictly speaking, he wasn’t wrong.

According to Haig, the forecaster was highly skilled, especially when it came to predicting weather in specific regions. He was remarkably accurate during the North African campaign – Eisenhower himself acknowledged that Krick ‘never got it wrong’ and consistently provided correct forecasts throughout the entire campaign.

It was incredible to watch how things played out! Stagg managed to convince the commanders to delay D-Day, and then, almost immediately, a huge rainstorm hit while everyone was at church in Southwark House on June 5th. I later learned that the church scene was a bit exaggerated for the film, but it really emphasized how right Stagg was about the weather.

Haig isn’t sure if it started raining at that exact time, but he believes the story is generally true.

Ike and Kay

Kay Summersby drove ambulances during the bombing raids of the Blitz. The movie suggests that her relationship with Eisenhower, who she worked for as a personal secretary, was more than just professional. While it’s confirmed she was at Southwark House with Eisenhower, there’s little proof she knew or worked with Stagg.

Haig explains that the biggest change he made when adapting the play for film was connecting the characters of Stagg, Eisenhower, and Kay. He admits that, historically, there wasn’t a strong connection between Stagg and Kay.

People have different views on the nature of Eisenhower and Kay Summersby’s relationship. According to historian Susan Maras, they were very close and deeply trusted each other. Numerous photos show them together, and she clearly had a significant impact on Eisenhower during that period, something the researchers wanted to acknowledge.

No matter how you see her connections to other characters, she clearly had a significant impact on the story, according to Haig.

Archival footage

Inspired by Peter Jackson’s 2018 World War I documentary, “They Shall Not Grow Old,” Maras decided to incorporate colorized historical footage into the film “Pressure.”

Maras explains that the D-Day scene includes actual historical footage of soldiers landing on the beaches. They combined this real footage with their own to create a more impactful and grand scale. It wasn’t just about showing large numbers of ships and vehicles; they also wanted to capture the personal toll of war, like the fear visible in a soldier’s eyes.

So, we ended up with over 50 hours of old footage – a total treasure trove! We brought in some research editors to start digging through it, and honestly, it was a lot. After just a few days, our director, Maras, was like, ‘Anyone know some extra hands we can bring on board to help with all this?’ It was clear we needed more people to tackle the mountain of film!

A man named James Stagg once worked with us, and surprisingly, eighty years later, his grandson came to our offices. He actually helped us edit the old movie clips we used in a film about his grandfather, which was quite a moment, according to Maras.

Stagg’s wife

Although Stagg’s wife, Elizabeth, isn’t featured in most of the play, the filmmaker, Haig, intentionally shows them together at the beginning and end. Haig explains that seeing Stagg’s loving side with his wife first provides important context for his behavior throughout the story. The audience then anticipates his return to her and their baby at the conclusion.

When Stagg traveled to Southwark House, his wife was expecting their child. Due to the need for secrecy around the D-Day landings, he wasn’t permitted to call and check on her. Contrary to what’s shown in the film, the hospital where she gave birth was never actually bombed.

According to Maras, the hospital bombing scene really shows the intense stress Stagg and his wife experienced before D-Day. The scene is meant to highlight Stagg’s worry for his wife’s safety, leaving the audience to wonder if she survived.

Truth to power

In the end, Stagg informs a gathering of military officials that the D-Day invasion must be delayed due to bad weather – a historically accurate detail. Maras wanted to highlight how he bravely challenged those in authority.

Maras describes the main character as someone who is bold and outspoken, willing to confront even the world’s most powerful military leaders and deliver an unwelcome message.

During John F. Kennedy’s inauguration, he asked Dwight D. Eisenhower what had been the key to success on D-Day. Eisenhower replied that they simply had more accurate weather forecasting than the Germans. This shows the importance of trusting the advice of experts, a lesson we should remember from history.

2026-05-30 01:02