WORLD WAR II

Weather’s Important Role

From the very first battle marking America’s involvement in World War II, weather played a major role. On November 26, 1941, a fleet of four aircraft carriers and several other ships under the command of Admiral Isoroku Yamamoto steamed away from Japan toward Oahu, Hawaii, twelve days and 4,000 miles away.

Most of the trip was very difficult, with high seas and cold, stormy winter weather, but the rough conditions helped the huge fleet avoid detection. When the ships finally anchored 220 miles north of Oahu on December 7, 1941, and prepared to launch a surprise attack on the US naval base at Pearl Harbor, America’s entry into the war was certain.

THE ALLIES STRIKE BACK

For the next four months, most of the news coming from the Pacific theater was negative, with defeats at Bataan and Corregidor disheartening the American public and military alike. On April 18, 1942, commander Jimmy Doolittle and his squadron of sixteen B-25 bombers (still 200 miles from their intended launch point) took off from the deck of the brand new aircraft carrier USS Hornet and turned toward Tokyo, more than 700 miles away.

Forced to take off early after the fleet was sighted by a Japanese patrol boat, the B-25s lumbered off the deck of the USS Hornet in a light rain. The B-25s had been stripped of any unnecessary equipment in order to carry more fuel, but on the way to Japan, they encountered a 20-mile-per-hour headwind that accelerated their fuel consumption. Arriving over Tokyo, the Raiders loosed volleys of 500-pound bombs on war-industry targets and then turned north along the coast toward China, where they hoped to find refuge.

It soon became obvious that the bombers wouldn’t have enough fuel to make it to the Chinese airfields due to the headwinds they had encountered earlier. The situation got even worse when they encountered fog over the East China Sea, followed by a hard rain. With visibility near zero, navigators were forced to rely on dead reckoning to chart their course.

Suddenly, the winds shifted and the bomber crews found themselves being propelled by a strong tailwind. Still unable to see through the storm and low on fuel, most of the planes were forced to ditch in the ocean. In the end all sixteen B-25s were lost, seven men were injured, and three were killed. Eight crew members were taken prisoner by the Japanese, and only four of them survived the war. But the raid not only gave American morale a huge boost after several crushing defeats, it also dealt a shattering blow to Japanese pride.

THE PLOESTI RAID

In the summer of 1943, Operation Tidal Wave was launched from a Libyan airfield against Nazi-held oil refineries in Ploesti, Romania. Once again the weather would have a marked influence on the outcome. To reach the target and return, the mission’s 179 B-24 bombers would have to fly more than 2,400 miles in eighteen hours. The flight over the Mediterranean was uneventful, with beautiful weather and unlimited visibility. Then, on reaching land, the bombers encountered a bank of huge cumulus clouds over the 9,000-foot peaks of the Pindus Mountains. Flying blindly through the clouds at 12,000 feet, the planes became separated into two groups, neither one aware of the position of the other.

Because one bomber group arrived over the target well in advance of the second, the late arrivals suffered heavy casualties since the Germans had been alerted to their presence. Although most of the planes were able to drop their bombs, many important targets were missed in the confusion. Of the 179 planes in the mission, only ninety-nine returned to base, and fifty-eight of the surviving planes suffered severe combat damage.

THE BEGINNING OF THE END

The end of the Third Reich began with the Allies’ Operation Overlord, a culmination of years of planning that aimed for the invasion of Europe and the end of the Führer’s stranglehold on the embattled continent. Under the command of General Dwight D. Eisenhower, five beaches along the coast of France near Normandy were chosen as landing sites, and thousands of troops that had been in training for the mission for up to two years were moved into position.

D-Day Weather


If Operation Overlord hadn’t taken advantage of the temporary break in the weather on June 6, the invasion might never have happened. Just a few days later, one of the worst June storms in English Channel history pounded the beaches, lasting for a full five days. Artificial harbors that had been created by the invaders at critical landing zones were completely destroyed by gigantic waves.


But before the giant operation could begin, several conditions had to be met in order to boost its chances for success. Low tide should coincide with the breaking dawn, giving the Allies the maximum amount of beach to work with. There should be a rising full Moon to support airborne operations, and a minimum visibility of 3 miles so naval gunners could see their targets. Winds should not exceed 8 to 12 miles per hour onshore, or 13 to 18 miles per hour offshore. No more than 60 percent of the sky should be covered by clouds, and they could not be lower than 3,000 feet.

Given these stringent requirements, forecasters estimated that there might be only three days in the entire month of June that would be suitable. Finally, June 5 was chosen as D-day, but after the troop ships and landing craft were loaded with men and supplies on the fourth, a storm system moved in over England. With high winds whipping across the English Channel and clouds hovering only 500 feet above its churning waves, Eisenhower was forced to delay the invasion.

On the night of June 4, Eisenhower’s chief meteorological adviser, James Stagg, informed him that there might be a temporary break in the weather on the sixth, and the general uttered the fateful words “Okay, we’ll go,” throwing the formidable Allied invasion machine into gear. Six thousand landing craft and other ships left British ports on their way toward France, along with the 822 gliders and other aircraft that would transport Allied soldiers behind enemy lines. The first wave would be followed by 13,000 bombers, sent in to soften Axis positions in advance of the invading forces. This time the weather cooperated, and although Allied losses were heavy, especially at well-defended Omaha Beach, the invaders soon controlled the coast of Normandy and began the long push toward Berlin.

THE FINAL COUNTDOWN

Just as weather had influenced the first major attack of World War II against US forces, Pearl Harbor, the atmosphere intervened again in the last one: the mission to drop the atomic bomb that ended the war with Japan. The job of ending the war was brought about not by the Enola Gay, the B-29 Superfortress that leveled Hiroshima, but by another B-29, the Bockscar, which bombed Nagasaki. Although the Enola Gay’s mission was aided by clear skies over its target, the Bockscar faced tougher conditions.

In fact the residents of Kokura, on the northeast corner of the Japanese island of Kyushu, had the weather to thank for sparing their lives on August 9, 1944, when the Bockscar took to the air. President Truman had offered to spare Japan further agony after Hiroshima’s destruction three days earlier, but promised that “if they do not now accept our terms, they may expect a rain of ruin from the air the like of which has never been seen on this earth.”

With no response from the emperor, Kokura was selected as the next primary target because of its automatic weapons factories. Two weather observation planes were dispatched to the city an hour before the scheduled bombing, since the bombardier would need a clear sightline to the target. Reports indicated there would be only a 30 percent cloud cover over Kokura, but when Bockscar arrived, the crew found the entire city socked in under a thick layer of clouds. Had the weather been more accommodating, the bomb would have no doubt killed a young Kokura college student named Tetsuya Fujita, who would later become famous for developing a tornado damage scale that still bears his name.

Frustrated, the crew turned toward their secondary target, Nagasaki, a major shipbuilding center. When they arrived, they found that it, too, was mostly buried under clouds. Against orders, the crew decided to bomb by radar rather than return to its base in Okinawa and attempt to land with a fully armed atomic bomb on board. In the last twenty seconds of the bombing run, the bombardier sighted the target through a break in the clouds and released the bomb. Fifty seconds later, at 11:02 a.m., the crew experienced a white-hot flash followed by a violent shock wave.

Five days after the attack, the Japanese announced their acceptance of the Allies’ terms of unconditional surrender.

The weather has been at the center of many major turning points throughout recorded history, and has been the single constant in all of mankind’s conflicts. In the near future it’s quite possible that advances in weather-control technology will allow people to use weather as a weapon.