TUCSON, Ariz. (KGUN) — March is here and that means spring is just around the corner! However, spring is already here in one aspect. March 1st marks the beginning of meteorological spring. What is meteorological spring? Well, meteorologists and climatologists like to recognize meteorological seasons based more on annual temperature cycles versus astronomical seasons that are based on the position of the sun in relation to Earth.
One reason for observing meteorological seasons is because meteorologists and climatologists are able to rely on more consistency when collecting climatological data for a particular season. Astronomical seasons can vary by a few days each year based on the sun’s position in relation to Earth. So, using meteorological seasons eliminates the inconsistency of calendar dates when using data based on astronomical seasons.
Also, meteorological seasons follow our civil calendar a little closer. For example, we generally see a significant temperature upswing when we reach the first week of March. It’s more reflective of the season to recognize the temperature trend difference at the first of the month. If we wait until the third week of the month, when the astronomical season starts, we’ve already observed a bigger change in weather trends since the first of the month.
In reality, this temperature difference between the first week and the third week of the month isn’t always the case. For instance, we began this month with a freeze in Tucson. However, most of the time, we can be pretty confident that the first week of the 1st month of the meteorological season will show a significant change in the weather trend.
No matter what season format you choose to follow, when the calendar turns to March, we know warmer temperatures are just around the corner! This also means our last average freeze is near. Usually, in Tucson, our average last freeze occurs on March 3rd. Dating back to the late 1800s, the latest freeze ever recorded in Tucson was May 3, 1899. Wow, that’s a late freeze! Here’s a look at some last freeze data from other communities across southern Arizona.
In case you’re wondering, this winter has given us our fair share of cold mornings but nothing too extreme. As of March 2nd, we’ve seen the mercury dip to 32° or below on 6 days since October 1st. Our coldest morning, to date, was when the low temperature dipped to 30° on January 10th. We may see some more freezing temperatures before we turn the corner towards summer, but chances quickly dwindle as we head into March.
March also brings a big increase in hours of daylight which translates into warmer average temperatures. In Tucson, average highs climb into the upper 70s and average lows climb into the upper 40s by the end of the month. March can also bring some much needed rain and snow to southeastern Arizona before we head into the drier months before monsoon.
No matter what format you choose to follow the seasons, meteorological or astronomical, spring is near and it won’t be long before summer is here. Enjoy the 70s and 80s while they last!