Happy first day of spring! Sort of...

Thursday marks the first day of 'meteorological spring'

By Justin Horne - Weather Authority Meteorologist/Reporter

SAN ANTONIO - Happy first day of spring! Sort of...

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Thursday marks the meteorological start of spring.  

While most people still go off of the astronomical seasons, many in the world of meteorology use a slightly different calendar.

Here’s why…

KSAT Weather: Beautiful weather for the end of the week

The astronomical seasons, which have been used for thousands of years, are based on the natural rotation of the earth around the sun: You have two equinoxes and two solstices.  

For the astronomical calendar, the spring equinox is March 20. Thanks to things like leap years and the elliptical shape of the earth’s orbit, the lengths of the astronomical seasons vary between 80 and 93 days. This variation makes it tough to compile and compare climatological statistics.

As a result, the meteorological season was born.  

The seasons are based on the grouping of three months. Meteorological spring includes March, April, and May. This creates a more consistent length for the season, making it much easier to compile weather statistics. This information is valuable to agriculture, commerce, and many others. 

So if you hear us say spring… you’ll know why. 

Thursday, Friday and weekend forecast

Meanwhile, the first day of the meteorological spring is turning out to be beautiful!  

Expect a mostly sunny day, along with warm temperatures in the mid to upper 70s.  

Winds are forecast to be gusty  out of the north through the afternoon.  

Tonight, temperatures will fall quickly, with 40s possible for a large portion of South Texas.

Friday looks equally as nice, with a high near 70 and partly cloudy skies.

As for the weekend, clouds make a return, as does the potential for fog and some patchy drizzle. 

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