Low-pressure area most active tropical cyclone basin on Earth. Wind is initially accelerated from areas of high pressure to areas of low pressure. This is due to density (or temperature and moisture) differences between two air masses. Since stronger high-pressure systems contain cooler or drier air, the air mass is denser and flows towards areas that are warm or moist, which are in the vicinity of low-pressure areas in advance of their associated cold fronts. The stronger the pressure difference, or pressure gradient, between a high-pressure system and a low-pressure system, the stronger the wind. Thus, stronger areas of low pressure are
Blood pressure 8 mmHg in the left atrium. Variants of venous pressure include: Normally, the pressure in the pulmonary artery is about 15 mmHg at rest. Increased blood pressure in the capillaries of the lung causes pulmonary hypertension, leading to interstitial edema if the pressure increases to above 20 mmHg, and to pulmonary edema at pressures above 25 mmHg. Disorders of blood pressure control include high blood pressure, low blood pressure, and blood pressure that shows excessive or maladaptive fluctuation. Arterial hypertension can be an indicator of other problems and may have long-term adverse effects. Sometimes it can be an acute problem,