Tag Archives: Seasons

Climatology, Colorado Weather, Thornton Weather

NOAA’s fall outlook predicts warmer and drier than normal conditions for Colorado

NOAA CPC Fall 2024 Temperature Outlook (NOAA)
NOAA CPC Fall 2024 Temperature Outlook (NOAA)

Tired of the heat of summer? Well, don’t power off that air conditioner just yet.

NOAA’s Climate Prediction Center’s autumn outlook for September, October and November, if accurate, would have us continue the above normal, drier than normal conditions of recent months.

The forecast gives above normal chances for most of the contiguous United States to see above average temperatures. For Colorado, the Four Corners region has the greatest chance at a likeliness of 60 to 70 percent. Most of the state, including the Front Range, is at a 50 to 60% chance.

In terms of precipitation, a good chunk of the nation has good chances to see below normal levels. The vast majority of Colorado is being given a 40 to 50% probability of below normal levels.

NOAA CPC Fall 2024 Precipitation Outlook (NOAA)
NOAA CPC Fall 2024 Precipitation Outlook (NOAA)Seasonal
Climatology, Thornton Weather

Astronomical winter arrives Thursday, offers up the shortest day of the year

The Winter Solstice
Winter officially begins at 8:27pm MST on Thursday, December 21, 2023.

Astronomical winter arrives in Thornton Thursday evening and with the solstice also comes the shortest day of the year.

Winter officially begins at 8:27pm MST on Thursday, December 21, 2023.

The Winter Solstice occurs when the North Pole is tilted at its furthest from the sun – 23.5 degrees away. This results in the shortest day of the year in the Northern Hemisphere.

Here in Denver, with sunrise at 7:17am and sunset at 4:38pm, our day Saturday will be 9 hours, 21 minutes and 14 seconds long.

The following day, Friday, it will be about a second longer and each day from now through to the Summer Solstice in June will get gradually longer as well.

While we have a short day on the solstice, it is nothing like what will be experienced in the Arctic Circle.  Areas north of there to the North Pole will have no direct sunlight at all.  Conversely, areas south of the Antarctic Circle toward the South Pole will have 24 hours of daylight and have a midnight sun.

Did you know that there is a difference between the astronomical seasons that we are discussing here and meteorological seasons?

Meteorological seasons differ slightly and are geared toward matching the calendar with the annual temperature cycle. This is done primarily for meteorological observing and forecasting and in many ways it is more logical than the astronomical seasons.

For the Northern Hemisphere, the meteorological spring covers the months of March, April and May. Summer brings the hottest months of the year and so meteorological summer is June, July and August. Meteorological fall then is September, October and November followed by the coldest months of December, January and February as meteorological winter.

Climatology, Thornton Weather

Astronomical winter arrives Saturday, offers the shortest day of the year

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The Winter Solstice
Winter officially begins at 9:28am MST on Thursday, December 21, 2017. (NOAA)

Astronomical winter arrives in Thornton Saturday evening and with the solstice also comes the shortest day of the year.

Winter officially begins at 9:19pm MST on Saturday, December 21, 2019.

The Winter Solstice occurs when the North Pole is tilted at its furthest from the sun – 23.5 degrees away. This results in the shortest day of the year in the Northern Hemisphere.

Here in Denver, with sunrise at 7:17am and sunset at 4:38pm, our day Saturday will be 9 hours, 21 minutes and 16 seconds long.

The following day, Sunday, it will be about a second longer and each day from now through to the Summer Solstice in June will get gradually longer as well.

While we have a short day on the solstice, it is nothing like what will be experienced in the Arctic Circle.  Areas north of there to the North Pole will have no direct sunlight at all.  Conversely, areas south of the Antarctic Circle toward the South Pole will have 24 hours of daylight and have a midnight sun.

Did you know that there is a difference between the astronomical seasons that we are discussing here and meteorological seasons?

Meteorological seasons differ slightly and are geared toward matching the calendar with the annual temperature cycle. This is done primarily for meteorological observing and forecasting and in many ways it is more logical than the astronomical seasons.

For the Northern Hemisphere, the meteorological spring covers the months of March, April and May. Summer brings the hottest months of the year and so meteorological summer is June, July and August. Meteorological fall then is September, October and November followed by the coldest months of December, January and February as meteorological winter.

Climatology, Thornton Weather

Astronomical winter arrives Friday, offers the shortest day of the year

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The Winter Solstice
Winter officially begins at 9:28am MST on Thursday, December 21, 2017. (NOAA)

Astronomical winter arrives in Thornton Friday afternoon and with the solstice also comes the shortest day of the year.

Winter officially begins at 3:23pm MST on Friday, December 21.

The Winter Solstice occurs when the North Pole is tilted at its furthest from the sun – 23.5 degrees away. This results in the shortest day of the year in the Northern Hemisphere.

Here in Denver, with sunrise at 7:17am and sunset at 4:38pm, our day Friday will be 9 hours, 21 minutes and 16 seconds long.

The following day, Saturday, it will be one second longer and each day from now through to the Summer Solstice in June will get gradually longer as well.

While we have a short day today, it is nothing like what will be experienced in the Arctic Circle.  Areas north of there to the North Pole will have no direct sunlight at all.  Conversely, areas south of the Antarctic Circle toward the South Pole will have 24 hours of daylight and have a midnight sun.

Did you know that there is a difference between the astronomical seasons that we are discussing here and meteorological seasons?

Meteorological seasons differ slightly and are geared toward matching the calendar with the annual temperature cycle. This is done primarily for meteorological observing and forecasting and in many ways it is more logical than the astronomical seasons.

For the Northern Hemisphere, the meteorological spring covers the months of March, April and May. Summer brings the hottest months of the year and so meteorological summer is June, July and August. Meteorological fall then is September, October and November followed by the coldest months of December, January and February as meteorological winter.

Climatology, Thornton Weather

Winter Solstice brings shortest day of the year, change of seasons

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The Winter Solstice
Winter officially begins at 9:28am MST on Thursday, December 21, 2017. (NOAA)

Astronomical winter arrives in Thornton Thursday morning and with the solstice also comes the shortest day of the year.  Mother Nature as well appears set to bring in winter with a bit of a bang and a change in our recent mild, dry weather pattern.

Winter officially begins at 9:28am MST on Thursday, December 21.

The Winter Solstice occurs when the North Pole is tilted at its furthest from the sun – 23.5 degrees away. This results in the shortest day of the year in the Northern Hemisphere.

Here in Denver, with sunrise at 7:17am and sunset at 4:38pm, our day Thursday will be 9 hours, 21 minutes and 16 seconds long. The following day, Friday, it will be three seconds longer and each day from now through to the Summer Solstice in June will get gradually longer as well.

While we have a short day today, it is nothing like what will be experienced in the Arctic Circle.  Areas north of there to the North Pole will have no direct sunlight at all.  Conversely, areas south of the Antarctic Circle toward the South Pole will have 24 hours of daylight and have a midnight sun.

Did you know that there is a difference between the astronomical seasons that we are discussing here and meteorological seasons?

Meteorological seasons differ slightly and are geared toward matching the calendar with the annual temperature cycle. This is done primarily for meteorological observing and forecasting and in many ways it is more logical than the astronomical seasons.

For the Northern Hemisphere, the meteorological spring covers the months of March, April and May. Summer brings the hottest months of the year and so meteorological summer is June, July and August. Meteorological fall then is September, October and November followed by the coldest months of December, January and February as meteorological winter.

Astronomy

Winter Solstice brings shortest day of the year, change of seasons

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The Earth at the Winter Solstice. (NASA)
The Earth at the Winter Solstice. (NASA)

Astronomical winter arrives in Thornton today and with the solstice also comes the shortest day of the year.

Winter officially begins at 4:03pm today.  The Winter Solstice occurs when the North Pole is tilted at its furthest from the sun – 23.5 degrees away.  This results in the shortest day of the year in the Northern Hemisphere.

Here in Denver, with sunrise at 7:18am and sunset at 4:39pm, our day today is 9 hours, 21 minutes and 13 seconds long.  Tomorrow it will be one second longer and each day from now through to the Summer Solstice in June will get gradually longer as well.

Did you know that there is a difference between the astronomical seasons that we are discussing here and meteorological seasons?

Meteorological seasons differ slightly and are geared toward matching the calendar with the annual temperature cycle.  This is done primarily for meteorological observing and forecasting and in many ways it is more logical than the astronomical seasons.

For the Northern Hemisphere, the meteorological spring covers the months of March, April and May.  Summer brings the hottest months of the year and so meteorological summer is June, July and August.  Meteorological fall then is September, October and November followed by the coldest months of December, January and February as meteorological winter.

Thornton Weather, World Weather

Winter comes to a close as spring begins on Sunday

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Why do we have seasons?
Why do we have seasons? It is all thanks to the tilt of the Earth's axis. (NASA / NOAA)

We are now in the waning hours of winter as spring is set to arrive in Thornton later today – at 5:21pm to be exact.  The changing of the seasons from winter to spring means longer days, warmer temperatures and a greening landscape.

The Earth experiences seasons thanks to its 23 1/2 degree tilt.  As the planet circles the sun, a process that takes 365 1/4 days, different parts of the Earth are tilted closer to or farther away from the sun.

The vernal equinox (the first day of spring) is the day on which the sun is directly over the Earth’s equator and daylight lasts 12 hours in both the Northern and Southern Hemisphere.  This is because at this point the Earth’s axis is 90 degrees away from the sun.

From now until the summer solstice, those of us in the Northern Hemisphere get closer to the sun and thus enjoy the warming temperatures and experience spring and summer.  In the Southern Hemisphere they experience the opposite and for them today is the first day of autumn.

Animated vernal equinox
The vernal equinox brings nearly equal daytime and nighttime across the globe.

Here is Colorado, thanks to our northern latitude, we have already passed the point of 12 hours of equal daytime and nighttime, something that occurred just a few days ago.  Today in fact daytime will last 12 hours and 7 minutes.

Did you know that there is a difference between the astronomical seasons that we are discussing here and meteorological seasons?

Meteorological seasons differ slightly and are geared toward matching the calendar with the annual temperature cycle.  This is done primarily for meteorological observing and forecasting.

For the Northern Hemisphere, the meteorological spring covers the months of March, April and May.  Summer brings the hottest months of the year and so meteorological summer is June, July and August.  Meteorological fall then is September, October and November followed by the coldest months of December, January and February as meteorological winter.

Thornton Weather

First day of fall brings summer-like weather

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Today at 9:44am marks the Autumn Equinox – the first day of fall.  The days are definitely getting shorter and we are seeing less and less daylight.  The spring and autumn equinox mark the two days of the year  when the center of the Sun will spend a nearly equal amount of time above and below the horizon at every location on Earth and night and day will be of nearly the same length.  In short, there is 12 hours between sunrise and sunset.  Here along the Front Range we are pleased to see summer-like weather today and for most of the week. 

A dry and stable weather pattern will settle in over much of the state and with it usher in well above normal temperatures.  The normal high temperature for this time of year is 75 degrees and on Monday we will be a good bit above that as we reach 85.  There will be a slight chance for thunderstorms late today but those will be few and far between. 

As the week progresses we will continue to see above normal temperatures with 80 on Tuesday, 82 on Wednesday, 85 on Thursday and 84 on Friday.  Enjoy it while you can – the snow could be flying any day now!