In some cultures in the Northern Hemisphere, the astronomical March equinox (varying between 19 and 21 March) is taken to mark the first day of spring, and the Northern solstice (around 21 June) is taken as the first day of summer. In other traditions, the equinox is taken as mid-spring.
Circulation problems that cause dizziness. You may feel dizzy, faint or off balance if your heart isn't pumping enough blood to your brain. Causes include: 1  Drop in blood pressure.
A single lower-than-normal reading is not cause for alarm if you are not experiencing any other symptoms or problems. However, a sudden drop in blood pressure --- even a change of just 20 mm Hg --- can cause dizziness or fainting. Sometimes a rapid decrease in blood pressure can indicate an underlying problem such as: 1  Uncontrolled bleeding. 2  Severe infections.