Weather seems to have played a major role in some of history’s most important moments, especially in warfare.
The Battle of Gettysburg, over a century and a half ago, proved to be one of the bloodiest battles and a turning point in the Civil War. Between July 1 and 3, 1863, the Union and Confederate armies squared off in Gettysburg, Penn., and the weather turned terrible, which could very well be to blame for the jump in casualties to an estimated 50,000 — the most ever on American soil.
The interesting piece here, at least from a weather lens, is that we have the actual weather conditions recorded on each of the battle days. Rev. Dr. Michael Jacobs, a math professor at Pennsylvania College (now known as Gettysburg College), recorded the weather each of the three days of battle, and wrote the “Meteorology of the Battle.”
July 1 and July 2
It’s worth noting that just days prior, temperatures were in the mid-60s, but rain played a part in delaying the battle.
The first day of the square-off saw the best conditions, with a mostly dry ground and temperatures reaching the mid-70s. There was also a light breeze while the skies stayed mostly cloudy. But breeze or not, temperatures were still pushing to a level where soldiers became hot and exhausted with heavy wool uniforms and carrying all sorts of weaponry and rations.
On July 2, the sky remained mostly cloudy with some clearing in the afternoon. The added sunshine pushed temperatures into the low 80s, increasing the vulnerability for soldiers to heat exhaustion and heat stroke. Winds remained calm.
July 3 — Severe thunderstorm arrives
The morning started cool and cloudy, with temperatures in the low 70s just after sunrise. The afternoon turned hot with increasing sunshine, pushing temperatures to 87 degrees at 2 p.m. Notes from Rev. Dr. Jacobs described a “massive thunder-cloud of summer” in the vicinity of the battlefield.
It seemed as if two storms were happening at the same time, on the ground and in the sky — as Jacobs added, “the thunder seemed tame, after the artillery firing of the afternoon.” Wet powder led to many misfires, and trying to march and position heavy artillery in the mud was nearly impossible during the storm.
The heavy rain left its mark on the battlefield and, unfortunately, most likely drowned the folk who lay wounded on the ground. Rainwater overflowed nearby creeks and spilled into camps and making walking around very challenging.
The day after the battle, on July 4, soldiers had to trek 18 miles to the next camp across terrible road conditions from flood water, making the largest battle of the Civil War just that much more gut-wrenching.
Ken Mahan can be reached at ken.mahan@globe.com. Follow him on Instagram @kenmahantheweatherman.