Barometric Pressure and Migraines: What the Research Actually Says
Barometric pressure is the most studied weather migraine trigger. Here is the proposed mechanism, the key studies, and an honest look at how strong the evidence really is.
Barometric pressure is the weather factor most consistently linked to migraine. The leading explanation is that a rapid drop in outside air pressure, the kind that precedes storms, creates a small pressure imbalance with the air- and fluid-filled spaces in the head, which can trigger an attack in sensitive people. The evidence is real but mixed: several studies find a clear link, while a few rigorous diary studies find only a weak one.
Educational use only. This article summarizes published research and reputable sources for general information. It is not medical advice and is not a substitute for diagnosis or treatment by a qualified healthcare professional. Always consult your doctor about your migraines and before changing anything about your care.
Of all the ways weather might affect a migraine, barometric pressure is the one with the most research behind it, and the one Migraine Weather watches most closely. Here’s what’s actually known.
What barometric pressure is
Barometric pressure (also called atmospheric pressure) is simply the weight of the air above you pressing down. It’s usually measured in hectopascals (hPa) or inches of mercury (inHg). Standard pressure at sea level is about 1013 hPa, or 29.92 inHg.
Pressure isn’t constant. It rises in fair, settled weather and falls as low-pressure systems, meaning storms and rain, move in. That’s why an old-fashioned barometer can “predict” rain: a falling needle means a storm is on the way. It’s also why your head may register a change before the first raindrop falls.
What’s probably happening in your head
Your body contains air- and fluid-filled spaces, most notably the sinuses, that normally sit in balance with the pressure outside. When outside pressure drops quickly, that balance is briefly disturbed. The leading hypothesis is that this small imbalance, acting on sensitive structures and blood vessels in and around the head, helps trigger the nerve and vascular changes of a migraine.
It’s worth being clear about one thing: the exact biology is still being worked out. What researchers have more confidence in is the association, the timing of attacks lining up with pressure changes, rather than the precise step-by-step cause.
What the studies found
- Okuma et al. (2015) had migraine patients log attacks alongside atmospheric pressure. Migraines clustered when pressure had fallen by about 6–10 hPa from the standard 1013 hPa, squarely the kind of drop that comes with an approaching low-pressure system.
- Mukamal et al. (2009) analyzed more than 7,000 emergency-department headache visits and found that lower barometric pressure, along with higher temperature, in the preceding days raised the short-term risk of a severe headache.
- The honest counterweight: a well-run prospective diary study by Zebenholzer et al. (2011) found only weak and inconsistent links between day-to-day weather and migraine in their group. An accompanying editorial, “Weather and migraine: can so many patients be wrong?” (Becker, 2011), caught the tension neatly: patients overwhelmingly report weather sensitivity, yet group studies don’t always confirm a large effect.
So is it real?
The fairest conclusion is yes, for some people. Weather sensitivity isn’t universal, and averaging across everyone, weather-sensitive or not, naturally dilutes the signal. If you personally notice attacks around storms and pressure drops, the research gives you good reason to take that seriously rather than dismiss it.
The way to settle it for yourself is data: log your migraines together with the conditions at the time, then look for the pattern over a few weeks. That’s exactly what Migraine Weather is built to do. It records the pressure, temperature, and humidity automatically when you log an attack, so your personal pattern emerges without extra work.
Next
- What Barometric Pressure Triggers Migraines?, the specific numbers and thresholds.
- Why Do I Get a Migraine Before It Rains?, the hours-before-the-storm play-by-play.
Frequently asked questions
Does low barometric pressure or a change in pressure trigger migraines?
The change appears to matter more than the absolute level. Studies most often implicate a rapid fall in pressure rather than simply being at low pressure, which is why an approaching storm, when pressure is dropping fastest, is a common flashpoint. Sitting in a sustained low-pressure system can contribute too, but the drop is the main signal.
How big a pressure change can trigger a migraine?
Drops on the order of 6–10 hPa (about 0.18–0.30 inHg) from normal pressure are the range most frequently associated with attacks in the research, though some weather-sensitive people report reacting to smaller changes.
Why do some people react to pressure and others don't?
Migraine susceptibility varies enormously from person to person, and weather sensitivity is just one dimension of that. Genetics, baseline migraine frequency, and other co-occurring triggers all play a part. This variation is exactly why population studies sometimes show only a modest average effect even though weather-sensitive individuals are clearly affected.
Sources
- Okuma H, Okuma Y, Kitagawa Y. Examination of fluctuations in atmospheric pressure related to migraine. SpringerPlus. 2015;4:790.
- Mukamal KJ, Wellenius GA, Suh HH, Mittleman MA. Weather and air pollution as triggers of severe headaches. Neurology. 2009;72(10):922-927.
- Zebenholzer K, et al. Migraine and weather: a prospective diary-based analysis. Cephalalgia. 2011;31(4):391-400.
- Becker WJ. Weather and migraine: can so many patients be wrong? Cephalalgia. 2011;31(4):387-390.