PHOENIX -- For the fifth consecutive day, the mercury sweated out another record high temperature.

It was 94 degrees Sunday, breaking the old record for the date of 91 degrees set in 2004.

Sunday morning's low of 65 degrees also established a record for the warmest minimum temperature for the date, breaking the old mark of 62 set in 2004.

Here are the other record highs set the past few days:

Saturday: 99 degrees breaks old record of 92 in 1972.

Friday: 99 degrees breaks old record of 95 in 1921. It marked the hottest reading so early in a calendar year and the second hottest day ever recorded in March.The all-time record high temperature for March is 100 degrees set on March 26, 1988.

Thursday: 92 degrees breaks the old record of 91 in 1934.

Wednesday: 91 degrees breaks the old record of 90 set in 1934.

An unusually strong high pressure system over the region produced the record-shattering heat.

A weak low pressure system has moved towards Arizona from the southwest, which is helping weaken the upper level high, leading to somewhat cooler readings.

Vernal Equinox Begins On Tuesday

While it may feel like summer, spring officially begins at 5:07 p.m. Tuesday, March 20, marking the sun's halfway point of its six-month journey northward.

The crossing of the sun directly over the equator is known as the vernal equinox. The sun will continue its northward move until the summer solstice on June 21.

This is the time of year when days and nights are near equal length. This is also the time of year when the run rises directly in the east and sets directly in the west.

On Tuesday, the sun will rise at 6:37 a.m. and set at 6:37 p.m.

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