- March 1 begins the meteorological spring.
- This is different from the spring equinox, which takes place on March 20th.
- Meteorological seasons are based on temperatures, not strictly on the position of the sun.
The meteorological spring arrives on Monday and although you may be itching for warmer weather, you may be wondering why this is happening weeks before equilibrium.
After some record-breaking cold and repeated snow in February, spring could not come soon enough for those affected by crippling power and water outages in Texas and surrounding states.
It seems that spring is already here, at least according to meteorologists.
The coming of spring that you have probably heard of before is known as the spring equinox.
This is the moment in time when the sun’s most direct rays shine on the equator. In 2021, the equilibrium will take place on Saturday 20 March at 05:37 EDT. If you get up early on a weekend morning, you can observe it this year.
The autumn peer, the autumnal equinox, and also the summer and winter solstice, all occur at the end of September, June, and December, respectively, due to the tilt of the Earth’s axis as it orbits the sun.
This changing solar angle throughout the year is why we have so-called astronomical seasons.
(MORE: March Temperature forecast)
The orientation of the earth in relation to the sun on the northern hemisphere’s spring equinox, summer solstice, autumn equinox and winter solstice.
(NOAA / NWS)
Why do meteorologists deviate from the seemingly concrete definitions?
It all has to do with temperatures.
If you examine the average daily highs and lows during the year, you quickly see a pattern.
The coldest three months of the year in the Northern Hemisphere are usually from early December to late February, while the warmest three months are usually from early June to late August.
These beautiful, clean three-month buckets are known as meteorological winter and summer, respectively.
And these three-month clean buckets do not fit so well with the astronomical seasons, for example, late December to late March.
A generic example track of average high (red) and low (blue) daily temperatures per year. The coldest three months of the year are known as meteorological winter. The hottest such three months is meteorological summer. The transition between these two is meteorological spring and autumn.
(NOAA / NWS)
In fact, Alaska’s climate scientist Brian Brettschneider has calculated that the meteorological winter of December 1st – February 28th a better fit at the coldest time of the year in most of the United States and Canada.
In a analysis of dozens of US cities, Brettschneider found that only Honolulu, Hawaii, extended its coldest 90-day period to March.
For those living in the north of the US, it makes sense.
It seems a bit silly when we say ‘winter is here’ just a few days before Christmas, when many parts of the north have already had at least one significant snowfall or cold snow.
Meteorological spring – March 1 to May 31 – is the transition between the three coldest and three warmest months of the year.
Another advantage for meteorological seasons is the ease of calculating seasonal statistics, as each meteorological season begins on the first of the month.
A march of increasing daylight, temperatures
Most of the US will pick up a full hour of daylight when it arrives on March 14th.
Even if there were no sun savings, most areas in the northern US would get 30-45 minutes of extra sunlight by the end of March. More areas in the south will usually only pick up 15 to 30 minutes of extra daylight during the month if our clocks do not jump forward.
Sunset times on March 1 (before sunlight) and March 31 (after daylight saving time) in 2021 in different US cities.
(Data: NOAA; table: infogram)
While March has a well-deserved stormy reputation, including winter storms in the West and North America, with the sun gradually rising higher in the sky, average high temperatures usually rise by about 10 degrees in the Middle East by the end of the month. , Northeast and the Plains.
(MORE: When can you expect the first 70s and 80s of the spring where you live?)
Daily average high temperatures on March 1 and March 31 in several U.S. cities. The largest temperature change during the month occurs in the northern United States, especially the Plains and the Middle East.
(Data: NOAA; table: infogram)
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