cause > weather...

Several studies...

have found some migraines are triggered by changes in weather. One study noted that 62% of the subjects in the study thought that weather was a factor, in fact 51% were actually sensitive to weather changes. While those whose migraines did occur during a change in weather, often the subjects picked a weather change other than the actual weather data recorded. Most likely to trigger a migraine were, in order:

• Temperature mixed with humidity. High humidity plus high or low temperature was the biggest cause.
• Significant changes in weather
• Changes in barometric pressure

Another study looked at chinook winds (warm westerly winds occurring in Alberta, Canada) as a possible migraine trigger. Many patients had increased incidence of migraines immediately before and/or during the chinook winds. The number of people reporting migrainous episodes during the chinook winds was higher on high-wind chinook days.