Celebrate the Winter Solstice & Yuletime

The Winter Solstice happens at 12:30 a.m. EST tomorrow. The Sun's rays will be directly over the Tropic of Capricorn and at their lowest point in the sky in the Northern Hemisphere. Theoretically, it is the "shortest" day of the year. Enjoy this video celebrating the Winter Solstice.

Paul

The First Snowstorm of 2009-2010 Season Happened Two Years Ago Today

The first major snowstorm of 2009-2010 blasted southwestern Connecticut two years ago today, with some local communities receiving close to a foot of snow. Fortunately, the storm arrived late Saturday evening, December 19, 2009, giving most people ample time to prepare well in advance. The highest snow totals were recorded across southeastern Connecticut, while parts of Litchfield County saw nothing more than a trace of snow.

Here is a look at snowfall totals from across the region from December 19 and 20, 2009:

• Darien: 10.5"
• New Canaan: 10.3"
• Milford: 10"
• Bridgeport: 9"
• Fairfield: 9"
• Norwalk: 8"
• Woodbridge: 7.5"

Officially, at Sikorsky Memorial Airport in Stratford, six inches of snow fell Saturday, and 3.2 inches accumulated Sunday, December 20, 2009, for a total of 9.2 inches. The snow happened one day before the Winter Solstice. Over a foot of snow (13.4") was recorded at the airport in December 2009, including two inches on December 9, and just over two inches on New Year's Eve day.



The normal average snowfall for December is 3.6 inches, based on 40 years of averages, or climatology. The snowiest December day on record in southwestern Connecticut happened December 19, 1948, when 16 inches blanketed the region. You may recall that last year, a foot of snow fell from December 26 through December 27, triggering one of the snowiest periods in recent memory. You may also recall the Winter storm of December 30, 2000, when ten inches fell.

The weather computer models are hinting at a Winter storm developing late Christmas Eve Day and continuing into Christmas morning. However, before the holiday weekend, some rain is likely Wednesday, and showers are expected Friday as the holiday season gets into high gear. Are you dreaming of a White Christmas? I know I am.

Paul

Winter Solstice Just Six Days Away

Is it really mid-December? Temperatures were in the lower 50s at 3 o'clock this morning when I arrived at the weathercenter. That's a good ten degrees above the normal high temperature for the day. In fact, this month has been much warmer than normal. The average temperature thus far this month is 42.4 degrees, which is a whopping 4.5 degrees above normal. We're on pace to break the mark for the warmest December on record, which was 41.4 degrees in 2001.

Believe it or not, we're less than a week away from the start of Winter in the Northern Hemisphere. Winter officially arrives next Thursday, December 22, at 12:30 a.m. Whenever I visit a school to conduct my Weatherkids program, many schoolchildren ask me why the start of a new season doesn't begin at midnight on a certain date, much like the beginning of a new year. The answer has to do with the Earth, the tilt on its axis, and its revolution around the Sun.

I've always maintained that the start of a new season is more of an "event" than watching the ball drop in Times Square on New Year's Eve. That's because New Year's Day is a "man-made" holiday which can arbitrarily occur at any time during a calendar year. An equinox or a solstice, however, marks a precise time when the Sun's rays strike a particular point on the face of the Earth. I try to observe the arrival of a new season, and next Thursday will be no exception.

As the Earth travels around the Sun in its orbit, the North-South position of the Sun changes over the course of the year due to the changing orientation of the Earth's tilt with respect to the Sun. The dates of maximum tilt of the Earth's equator correspond to the Summer Solstice and Winter Solstice, and the dates of zero tilt correspond to the Vernal Equinox and Autumnal Equinox.

In the Northern Hemisphere, the Winter Solstice is day of the year when the Sun is farthest South. However, in the Southern Hemisphere, the Winter and Summer Solstices are the opposite, so that the Winter Solstice occurs on the first day of Summer in the Northern Hemisphere. The Sun's direct rays will be over the Tropic of Capricorn next Thursday morning.

The Winter Solstice also marks the "shortest day" of the year in terms of daylight. The length of time elapsed between Sunrise and Sunset at the Winter Solstice is at a minimum for the year. Of course, Daylight Saving Time means that the last Sunday in March has 23 hours and the first Sunday in November has 25 hours, but it does not correspond to the actual number of daylight hours.

Finally, the shadows cast by the Sun will be at their longest next weekend, since the Sun is at its lowest point in the sky. The actual times of Sunrise and Sunset in southwestern Connecticut for the Solstice are 7:16 a.m. and 4:27 p.m., respectively. Consider that on the first day of Summer in late June, the Sun rises at 5:19 a.m. and sets at 8:30 p.m. So, next Thursday's "length of day" is only nine hours and 11 minutes as opposed to 15 hours and 11 minutes exactly a half-year later.

So, as we prepare to welcome Winter, also realize that next Thursday marks a turning point. The days will gradually begin to get longer from this point forward until the end of June. Things can only get brighter from here on out. This weekend, though, it will begin to feel more like Winter. Daytime temperatures will struggle to reach the upper 30s and lower 40s under partly sunny skies. On the bright side, though, it will mark the seventh straight dry weekend across southwestern Connecticut.

Paul

The Odds of a White Christmas

This morning featured some of the coldest temperatures of the season. The mercury dropped into the teens inland and low-to-mid 20s just before daybreak, and a coating of frost caused car windshields, lawns, and rooftops to glisten from the light of the waning Moon.

Christmas is less than two weeks away, and many people have asked me about the odds of seeing a "White Christmas." Other than the historic Nor'easter the last weekend of October, we haven't seen any snow the last two months. Although showers are expected this Thursday and an offshore storm should stay far enough away early this weekend, there aren't any snowstorms in sight. I am watching the potential for a possible Wintry mix next Tuesday, however.

So, what are the chances of snow by Christmas? Here in southwestern Connecticut, weather records have been kept for a long time. Our climatology is based on record-keeping over a 40-year period. Based on history, shoreline communities such as Stamford, Darien, Stratford, and Milford have a 30% chance of seeing at least one inch of snow on the ground by December 25. There's a 10% chance of at least five inches of snow on the ground by then. However, we have a zero percent probability of having ten inches of snow or more on our front lawns by Christmas morning.



Inland, the odds are more favorable. People living north of the Merritt or Wilbur Cross parkways have a 57% chance of at least one inch of snow for Christmas. The odds are slightly lower than one-in-four (23%) for five inches of snow, and quite slim (3%) for at least ten inches of snow. However, residents in Wilton, Redding, Easton, and Woodbridge have a much better opportunity of seeing snow on the ground than their shoreline counterparts.

As far as the rest of New England is concerned, the chance of a white Christmas gets even better. Northern Connecticut and southern Massachusetts have about a 40 to 60% chance of at least one inch of snow; central New England's chances improve to 60 to 80 percent; and northern New England (80 to 100%) is virtualy assured of having a White Christmas.

One of the more memorable snowstorms which occured in late December was the Christmas Eve storm of 1966. We received over a half-foot of snow (6.9"), making roads quite slippery and travel very difficult. I distinctly remember my family on our way to visit my grandmother in the snow, but my parents deciding the drive wasn't worth the risk. We turned around and headed for home, but the car slid several times on the snowy roadways.

You may recall the snowstorm which delivered more than nine inches of snow to southwestern Connecticut the weekend of December 19 and 20, 2009. The snow began late Saturday evening, and six inches had accumulated by midnight. The snow tapered off early Sunday morning, but not before another 3.2 inches caused headaches for holiday shoppers the last weekend before Christmas.

Another recent snow occurred on Christmas Day, 2002. Some light snow happened early that morning, but a steadier and heavier snow developed by later in the afternoon and evening. The snow totals were quite impressive locally. Darien received 10 inches of snow by the time the storm exited the following day. Redding (9.5"), New Canaan (9.2"), Norwalk (7.0"), Greenwich (7.0"), and Westport (6.5") each saw at least a half-foot of snow!

On the flip side, I'm sure you recall December of  2006. The afternoon high temperatures from December 23 to 26 reached 58, 52, 44, and 50 degrees respectively, well above the 38-degree normal high. Over an inch of rain fell December 23 (1.15") and over a quarter-inch (0.28") was recorded on Christmas Day. We were left dreaming of snow for quite some time.

Paul

Full "Long Night" Moon Happens Tonight

Mostly clear skies, a light wind, and high pressure overhead gave us one of the coldest mornings of the season. The nearly Full Moon illuminated the frost on rooftops, lawns, and car windshields this morning as I made my way to work just after 3 o'clock. The Full Moon happens tomorrow morning at 10:36 EDT. The December Full Moon is known by a variety of names, including the Full Cold Moon and the Full Long Night Moon.

Why is it called the Full Long Night Moon? During December, the Winter cold fastens its grip in the Northern Hemisphere, and nights are at their longest and darkest. The term Long Night Moon is also an appropriate name because the early Winter night is long, and because the Moon is above the horizon for a long time. The midwinter full Moon has a high trajectory across the sky because it is opposite a low Sun.

In fact, the December Full Moon has been referred to as the Oak Moon, the Frost Moon, the Cold Moon, and the Moon Before Yule. No matter what the name, the Full Moon in December is directly opposite the Sun; therefore it is out for a long time. Since the Moon appears to follow nearly the same path as the Sun in the sky, the amount of time the Moon spends above the horizon varies as it orbits the Earth. The Moon is Full when it is opposite the Sun in the sky, so a Full Moon rises roughly at sunset and sets at sunrise. Therefore, we only see Full Moons at night.

Six months from now, on the Summer Solstice, the longest day of the year when the Sun spends the most time above the horizon, the Full Moon spends the least amount of time above the horizon. On the other hand, on the Winter Solstice, the shortest day of the year when the Sun spends the least time above the horizon, the Full Moon spends the most amount of time above the horizon. The time spent above the horizon each night for the Full Moon varies throughout the year about as much as the length of the day.

More clouds are expected tonight, however, as a dry cold front approaches the region. The clouds will most likely obscure the viewing of the Full Moon. Temperatures will drop into the low-to-mid 30s by daybreak. Tomorrow will feature clouds giving way to sunshine, but it will be windy and colder with a high in the low 40s. This will be the sixth straight dry weekend across southwestern Connecticut. Now that's something to howl about!

Paul

Roger Ludlowe Middle School's Sixth-Graders the Featured Weatherkids of the Week

I visited with the sixth-grade Science classes at Roger Ludlowe Middle School in Fairfield yesterday, Wednesday, November 30. They were the featured Weatherkids this week.



Paul