Lord knows I don't want to add to the mountain of material in our culture glorifying war, and particularly the Second World War, but I find this non-combat related tale irresistible for some reason. That reason may be that it is awesome.

Most westerners, and certainly Brits and Americans, are familiar with the tale of the "D-Day" landings at Normandy, the focal point of Operation Overlord. Briefly, the strategic importance of Overlord cannot be overstated. It was the Allies' all-in effort to establish a foothold on the continent, the success of which directly precipitated the defeat of Nazi Germany. Had the landings failed on June 6, 1944, the war in Europe could have been prolonged by as much as a year as the Allies regrouped, rearmed, chose a new landing site, and so on. In those additional months/years, hundreds of thousands of additional civilians, Nazi death camp inmates, and combatants who survived the war might have ended up dead.

One crucial element of war that historians and popular consciousness never seem to appreciate is the weather. It's a wild card, and the history of war is a history of good or bad fortune with weather; anyone familiar with the American Revolution, for example, knows the number of occasions on which the tiny Continental Army was saved by "divine providence" – particularly at the Battle of Long Island, where a miraculous, dense fog allowed Washington's 9000 man army to escape siege and eventual destruction by a large, concentrated British force. Yep, we basically won that war because of fog (and the massive balls of pre-treason Benedict Arnold at the Battle of Valcour Island, but that's a story for another day).

The D-Day landings needed specific weather conditions to succeed. First, a low tide was essential. In deep water, men and vehicles would be drowned before they even reached the beaches. Second, clear skies were required to permit air cover, shelling of German defenses, and so on. Finally, and coincidental to the low tides/clear skies, a full moon was needed for night operation. OK? OK.

The moon/tide schedule in June 1944 allowed for a brief window from June 4-6. Weather on June 4 was rough and stormy. June 5 was not much better. The massive movement of ships, men, and supplies toward Normandy was already underway, and Eisenhower needed to decide if they should be turned back (no small feat) or proceed with the invasion – which, again, would probably fail spectacularly if the weather was adverse. So he turned to his meteorologist, Group Captain J.M. Stagg, a cantankerous Scotsman whose uniform included specially made pants to house his balls.

A few points.

First, weather forecasting over the English Channel today, using computers, radar, and satellites, is dead wrong 50% of the time. Not "a little off" but completely wrong. Stagg didn't have satellites and radar. Meteorologists of that era drew pressure maps by hand, searched their archives to find similar looking maps from past dates, and then predicted that whatever weather followed that pattern previously would happen again. It was…not a great system. It was what they had. They made the best of it. But it wasn't exactly a science.

Not pictured: giant balls

As Group Captain Stagg (side note: use any "Group Captain!" quote from Dr. Strangelove here) surveyed the nasty weather on June 4 and 5, he looked at his crude data and came upon the idea that there would be "a break" in the violent seas and thunderstorms on June 6. Stagg has stated, as most meteorologists of his era no doubt knew in their hearts, that this was based on "a hunch" and experience. Basically, the fate of the largest invasion force ever assembled was subject to the hunches of a Scotsman with a hand-drawn map of weather fronts. Eisenhower had grown to trust Stagg and accepted his forecast. So it was a hunch about someone else's hunch; Ike went with his gut and went with Stagg's gut. It really is a miracle that the invasion force was not consumed by a hurricane and the Kraken.

I have to wonder what, aside from liquor, was going through the Group Captain's mind as he put his balls on the table and said, "No worries, this weather will clear up by the time they reach Normandy." Surely he knew what a disaster awaited them if he was wrong. Thousands of men could have died. The Allied war effort could have been set back months or years. And if that happened, he would have been the goat for all of it. Stagg recalled one General Morgan telling him, "Good luck Stagg. May all your depressions be nice little ones. But remember, we'll string you up from the nearest lamp post if you don't read the omens right." That may have been putting it kindly.

Salut, Group Captain Stagg! Salut, giant balls!