It’s the stereotypical front-porch scene: a couple of old-timers complaining about aches and pains, and then predicting a storm is in on the horizon because of a feeling in a joint or bone.
It’s not just old knees or a beat-up shoulder than can send signals in advance of weather – some people report experiencing symptoms in their eyes as weather gets ready to change. Those issues seem to be most often accompanied by tingling, dizziness, and being mentally flustered. But whether in the eye or joints, what about an impending rain could cause any discomfort at all?
As a storm approaches, the area’s atmospheric pressure drops. This is what the weathermen talk about on the news as they explain that the low pressure system heading your way will be ruining your weekend plans or canceling school tomorrow. Atmospheric pressure is essentially the weight of the air in the atmosphere, and when a big storm is heading in, that can pressure drop — sometimes quickly enough to trigger quite a reaction.
A drop in pressure is a bit like a scuba diver coming up from extreme depths, except on a molecular level. Without the pressure of all that water, divers are required to wait for pre-determined amounts of time to decompress so air bubbles in their blood don’t expand and give them a painful and potentially fatal condition called decompression sickness (more commonly called the bends). Some doctors think that changes in the atmospheric pressure on land — such as those brought on by an impending change in the weather — can cause people with chronic pain or certain other conditions to experience sensations because of the minuscule pressure difference allowing cells to expand just a bit. It’s the same reason people’s feet swell on commercial flights — though the cabin is pressurized, it’s a little less so than you’d experience at home.
While sensitivity to pressure changes in the eyes doesn’t appear to cause more than a little discomfort and annoyance for people in normal environments, at extreme altitude it can be a different story. In part because atmospheric pressure is lower at altitude, some alpinists, soldiers, trekkers and others at very high altitudes report bleeding in the eye, known as High-Altitude Retinal Hemorrhaging. Often, the condition accompanies other signs of acute mountain sickness or other altitude-related malady like cerebral edemas, but the eye issues can also happen on their own. The good news is that a trip into the Catskills isn’t likely to trigger such a reaction. You’d probably need to be hiking high into the Himalayas or Andes to be at risk for such an issue, though people sometimes report altitude issues in places like Colorado.
So does a light head and slightly blurred vision mean there’s rain in the forecast? Maybe, but regardless you should have any unusual symptoms checked out by an eye care professional before letting the neighbors know that turning on the sprinklers is a waste of time.