The Surprise Storm That Nearly Doomed the Allied Invasion of Sicily

By 1943, the tide of World War II was shifting. After a string of early victories, Nazi Germany had suffered heavy losses against Russia on the Eastern Front, and a coalition of Allied armies—American, British and Commonwealth troops—had defeated the Axis Powers in North Africa.

When U.S. President Franklin D. Roosevelt and British Prime Minister Winston Churchill met in Casablanca, Morocco, in January 1943, they knew it was time to take the fight to enemy soil. The question was where.

The U.S. wanted to attack Germany directly through a large-scale invasion of Nazi-occupied France, but that would have to wait another year. The British successfully argued for a coordinated attack through Italy, the “soft underbelly” of Axis-controlled Europe. Sicily, the large Mediterranean island off the “toe” of Italy, was selected as the top-secret target for the massive Allied invasion, code-named Operation Husky.

“There was a real strong feeling that if Sicily fell, Mussolini's government would fall as well,” says World War II historian and author Mark Zuehlke, referring to Italian dictator Benito Mussolini. “They believed that his hold on power was so tenuous that Italy would surrender and that would take them out of the war.”

Involving 3,000 ships and more than 4,000 aircraft, Operation Husky was the largest amphibious invasion of World War II up to that point, surpassing even the D-Day landings at Normandy 11 months later. Yet in a preview of the weather challenges that would plague D-Day, Operation Husky was almost sunk by a surprise storm that wreaked havoc on the mission and claimed the lives of hundreds of Allied airmen and soldiers.

The German high command knew the Allies were planning some kind of attack in the Mediterranean, but thanks to an ingenious deception operation known as Operation Mincemeat, Hitler and his advisors weren’t sure if the invasion would happen in Greece, Corsica, Sardinia, the Balkans or Sicily. As a result, German and Italian forces were forced to spread their defenses across multiple locations, leaving Sicily vulnerable to a surprise attack.

The battle plan for Operation Husky was to land more than 150,000 Allied troops along a 100-mile stretch of Sicily's southern coastline, overwhelm Axis defenses and push north toward the Italian mainland. In addition to the ambitious amphibious assault, Operation Husky incorporated an untested tactic called “vertical envelopment,” in which airborne units—paratroopers and gliders—would simultaneously attack enemy defenses from the rear.

“The strategic advantages [of envelopment] were pronounced, not just from an attacking standpoint, but for blocking reinforcements from coming up from the rear, resupply, retreat, all those kinds of things,” says Scott McGaugh, a military historian and author.

For the envelopment strategy to work, however, thousands of paratroopers needed to drop behind enemy lines at precision locations to seize key roads, bridges and airfields. The plan also called for hundreds of gliders—large, unpowered aircraft towed into battle—to land quietly behind enemy lines and deliver even more troops and equipment for the rear attack.

“The gliders could hold about 40 men each, and could transport jeeps and small artillery pieces,” says Zuehlke, author of Operation Husky: The Canadian Invasion of Sicily, July 10–August 7. “If three gliders land in tandem right where you want them, you have 120 soldiers. That's equivalent to an entire company right there taking the enemy by surprise.”

Allied military strategists put a lot of faith in gliders, but in 1943 they were still a relatively new and unproven technology. Operation Husky marked the first large-scale combat use of gliders by the Western Allies, says McGaugh, author of Into the Firestorm: The Allied Heroes Who Flew WWII’s Most Daring Missions. By the end of the war, gliders had earned a grim nickname—"flying coffins"—thanks in part to the storm-ravaged mission in Sicily.

Flying a glider is difficult enough under normal circumstances, but Operation Husky turned out to be anything but normal, says McGaugh. First, it took forever for the gliders to arrive in the staging areas in North Africa. And when they did, some of the glider parts were shipped to the wrong bases, so it was a “mad dash” to assemble them in time.

Then British General Bernard Montgomery made a last-minute decision. Instead of executing the difficult airborne mission during the day, Montgomery ordered the paratroopers and gliders to fly at night. The airborne divisions were scheduled to take off from Tunisia late on the evening of July 9, with the amphibious landings beginning before dawn the next morning.

To further complicate things, Montgomery assigned British pilots to fly the American-made gliders, even though there was almost no time left to train them.

“Most of the British glider pilots had four hours of flight time in these gliders and nothing of any kind at night,” says McGaugh. “Now they're going to fly 450 miles across the Mediterranean in the middle of the night as the precursor to the invasion of Sicily.”

Montgomery assigned American pilots to tow the gliders, which were to be flown just 200 to 300 feet above the water to evade radar and then released at precisely the right moment to glide safely to their landing zones. The American pilots also had minimal glider-towing experience and none at night.

“And we haven’t even gotten to the weather yet,” says McGaugh.

The Mediterranean is the world’s largest enclosed sea, and its weather can be incredibly erratic, with powerful cold fronts swooping down from Scandinavia and colliding with hot air from Africa. Under the right conditions, the Mediterranean can even generate tropical-like cyclones known as “medicanes,” a portmanteau of Mediterranean and hurricane.

Weather forecasting was primitive in the 1940s, so the planners of Operation Husky had no idea that a severe storm was going to strike on the evening of July 9, just as the paratroopers and gliders were scheduled to take off.

"Canceling or delaying the invasion is not an option,” says Zuehlke. “If the Allies are going to achieve any surprise, they can't be sitting off the coast of Sicily for days. The Germans and Italians will say, ‘By Jove, I think they're going to invade us!’ So the air component has to go forward that night.”

Despite heavy rain and 40 mph winds, hundreds of Allied aircraft carrying paratroopers and towing gliders took off from Tunisia and began the five-hour flight to Sicily. The harrowing journey was made even more perilous by a shortage of navigators.

“Only one in four planes had a navigator, so three-fourths of the air armada was playing follow-the-leader,” says McGaugh. “If the first navigator miscalculated in the wind and the rain and the darkness, three more planes were going to follow him and be in equally dire straits.”

The storm was so bad that it nearly jeopardized the entire operation. Allied paratroopers were scattered over a 1,000-square-mile area in southern Sicily. Fewer than 1 in 34 landed anywhere close to their intended drop zone. Colonel James Gavin, a commander in the 82nd Airborne, was blown so far from his destination that he initially thought he landed in mainland Italy. Only the sound of distant explosions reassured him that he was in Sicily.

Glider pilots faced even worse odds. Buffeted by gale-force winds, some tow ropes simply snapped, surrendering the gliders to the dark ocean below. Other gliders were released too early, too low or too far off course. Of the 144 gliders that left Tunisia, only 12 reached their landing zones. Nearly 70 gliders crashed into the sea and more than 600 Allied soldiers were killed, half by drowning.

Despite inflicting heavy losses, the storm wasn’t enough to derail Operation Husky completely. The paratroopers were badly scattered, but they managed to regroup, improvise and sow chaos behind enemy lines. By the time the amphibious landings began on the morning of July 10, the only reminder of the storm was the choppy sea, which was still rough enough to make most of the infantrymen lose their breakfasts on the way to the beach.

The invasion of Sicily was ultimately a success. It took the Allies 38 days to defeat the stubborn Axis resistance and secure the island, including airfields that later served as launching points for bombing raids against targets in Romania and Germany. Operation Husky also contributed to the collapse of Mussolini’s regime, although the Allies continued to fight the costly Italian Campaign until the end of the war.

The most important legacies of Operation Husky were the lessons it taught the Allied commanders about the dangers and difficulties of amphibious invasions—lessons that were applied 11 months later on D-Day. McGaugh says that after Sicily, General Dwight D. Eisenhower became deeply skeptical about airborne operations due to the vulnerability and unreliability of gliders and paratroopers. “Eisenhower basically said, if we’re going to do this again, we have to get our act together.”

The other critical lesson learned from Sicily was the importance of weather forecasting. The D-Day invasion was famously delayed after Scottish meteorologist James Stagg advised Allied commanders that weather conditions were unsuitable for the planned June 5, 1944, launch. Stagg’s rain delay not only safeguarded the mission, but also contributed to a key element of surprise. German forecasters believed the storm was going to be so bad that the Allies would have to cancel D-Day entirely. They were wrong.