The weather report can tell you how cold it will be and whether to expect rain. But if you're prone to severe headaches, the forecast could also signal the start of debilitating head pain. Shifts in the weather—especially in the colder months—can sometimes trigger vascular headaches such as migraines and cluster headaches. You can't control the conditions outdoors. But just like you can wear extra layers and pack an umbrella, you can take steps to ease headache pain, whatever the weather. Is Your Head in the Clouds? Many people with migraines report climate-related triggers, including drops in barometric pressure, lower temperatures, bright sunlight, and higher humidity. In a recent survey, more than one-third of people with cluster headaches—episodes of pain that repeatedly strike one side of the head—said these types of weather changes bring on symptoms. In addition, susceptible children are nearly three times as likely to get a headache if it's humid or precipitating. Scientists aren't sure why weather brings on headaches or makes them worse. Drops in atmospheric pressure could cause your brain to release substances that lead to inflammation, swelling of blood vessels in your brain, and more sensitivity in your nerves. Genetic differences may explain why some people feel weather shifts in their heads and others don't. Spot Trends that Spark Symptoms Keeping a headache journal can help you determine if weather triggers your pain. After each headache, note factors such as: When it occurred How intense it was, and how long it lasted What the weather was like before and during What you ate and drank in the previous 24 hours How much you slept the night before Your days of your menstrual cycle, if you're a woman Share the notes with your doctor. This will help him or her diagnose your headache, pinpoint your triggers, and develop the best prevention and treatment plan. Stay Ahead of the Pain If you and your doctor note certain weather patterns that cause you pain, try to avoid them when you can. For instance, stay inside on rainy days, or shield your eyes from bright sunlight. In addition, do your best to avoid any other factors that seem to aggravate your symptoms. These may include smoke, perfume and other scents, loud music, red wine, or foods such as chocolate or nuts. In fact, you may even find that these triggers are more to blame for your headaches than is the climate. Checking the weather forecast can help you plan ahead and prevent pain. If you note dropping temperatures or other changes ahead, consider getting a massage, exercising, or trying biofeedback—any method that's helped you prevent or relieve pain in the past. Key Takeaways Shifts in the weather can sometimes trigger migraines and cluster headaches. Drops in atmospheric pressure can lead to swelling of blood vessels in your brain and more sensitivity in your nerves. Keeping a headache journal can help you determine if weather triggers your pain.