Blood pressure generally is higher in the winter and lower in the summer. That's because low temperatures cause your blood vessels to narrow — which increases blood pressure because more pressure is needed to force blood through your narrowed veins and arteries.
In addition to cold weather, blood pressure may also be affected by a sudden change in weather patterns, such as a weather front or a storm. Your body — and blood vessels — may react to abrupt changes in humidity, atmospheric pressure, cloud cover or wind in much the same way it reacts to cold. These weather-related variations in blood pressure are more common in people age 65 and older.
Other seasonal causes of higher blood pressure include weight gain and decreased physical activity in winter. If you have high blood pressure already, continue to monitor your blood pressure readings as the seasons change and talk to your doctor. Your doctor may recommend changing the dose of your blood pressure medication or switching to another medication. Don't make any changes to your medications without talking to your doctor.
If you have questions about how weather may affect your blood pressure, ask your doctor.