A Summer Reality Check in Late July

It finally hit me last night while watching my sons swim in our backyard pool. The Sun was setting earlier. That shouldn't be too surprising since today marks 40 days since the Summer Solstice, and we're just five days away from the midpoint of Summer. You’ve probably already begun to notice the subtle changes across southwestern Connecticut.

Here’s another point to ponder. Most school systems across southwestern Connecticut open their doors in a little more than four weeks. How is that possible? It seems like only yesterday we were watching our children celebrate the last day of school. That was over five weeks ago. August begins this Wednesday!

The days are indeed getting “shorter.” In fact, we have lost nearly an hour (47 minutes) of daylight since the first day of Summer. Sunrise on June 20st happened at 5:19. This morning’s Sunrise was at 5:47, 28 minutes later. Sunset is now at 8:10, 19 minutes before the latest Sunset, at 8:29, on the Solstice. The sky is getting darker much earlier.

By mid-August, the shorter days become even more pronounced, with Sunrise and Sunset times at 6:02 and 7:51, respectively. The “shorter” days have to do with the Earth’s revolution around the Sun, and the 23.5 degree tilt on its axis. By the end of September, the Autumnal Equinox begins a six-month period of longer nights and shorter days in the Northern Hemisphere.

Need further proof that we’re moving through Summer rather quickly? Training camps for National Football League teams opened last week. The New England Patriots open their preseason schedule one week from Thursday, August 9, at home against the New Orleans Saints. And, in what lately has become a rite of late-Summer, the three-time defending state champion Fairfield American 12-year-old Little League baseball team begins play in the New England Regional tournament later this week.

Today may very well be the best day of the week under a mix of sun and clouds with a high temperature near 80 degrees. Tonight will become mostly cloudy and mild with lows in the 60s. Tomorrow will be mostly cloudy and slightly cooler with a high of 75 to 80 degrees. Scattered showers and thunderstorms are possible Wednesday through the start of the weekend.

Paul

Severe Storms Expected This Evening

The National Weather Service Storm Prediction Center has placed our region in a moderate risk of strong-to-severe weather from late this afternoon through about midnight. The atmosphere will become quite warm and humid today as temperatures soar into the mid-to-upper 80s, fueling the formation of strong thunderstorms, which may include damaging winds, small hail, vivid lightning, and even the possibility of tornadic activity. In short, the threat of severe weather is enhanced this evening.

Nearly three-quarters of Connecticut, especially the Western half, has a five percent chance of a tornado along the line of severe storms this evening. The image below shows the shaded areas in the Northeast with the accompanying probability of tornadic development.

The air is certainly more humid this morning, and some light rain developed during the morning commute. A line of thunderstorms moved across Western Fairfield County between 9 o'clock and 9:45 this morning. A storm over the Great Lakes region will track to the East today, moving into the region late this afternoon and through the area later this evening. That's when the best chance of severe weather will happen, generally between 5 p.m. and midnight.

What does this mean for us? First of all, be prepared for power outages. Our Power Outage Index is registering a "likely" for much of the region early tonight. Damaging winds may bring down tree limbs, power lines, and small trees. Have flashlights with fresh batteries at the ready. Also, make sure storm drains are cleaned and not clogged. Heavy downpours may cause ponding and flooding of low-lying areas. Finally, if you have a generator, make sure it's ready with a full tank of gasoline. You can never be too prepared for violent weather.

A frontal boundary will become nearly stationary late tonight as waves of low pressure move along the front tonight into Friday. That will bring more scattered showers and thunderstorms. The frontal system will slowly push across and then East of the region Friday night through Saturday night. Spot showers and storms are possible through this weekend, especially Saturday, before weak high pressure arrives Sunday into the beginning of next week.

Paul

Sun's Shadows Getting Longer & Sun's Angle Getting Lower

Even though we're just a little more than a month removed from the Summer Solstice, there are subtle signs that the "longest day of the year" was five weeks ago. You may have noticed that the days are getting shorter, since the Sun rises 21 minutes later and the Sun sets 11 minutes earlier than it did on the first day of Summer. However, less discernible is the change in the length of shadows. Believe it or not, the shadows have been slowly getting longer, and that's due to the Sun's lower angle in the sky.

The Sun reached its highest angle in the sky --- or declination --- in the Northern Hemisphere on the first day of Summer. The declination of the Sun is the measurement of the angle between the Sun’s rays and the Earth’s equatorial plane. The Earth’s axis is tilted by 23.5 degrees away from the solar plane. This explains why we have different seasons and why the Northern Hemisphere and the Southern Hemisphere always have contradicting seasons. When tilted towards the Sun, it's Summer in the Northern Hemisphere.

The Sun’s declination varies throughout the year. Its declination becomes zero during the Spring Equinox and reaches the maximum declination angle of 23.5 degrees during the Summer Solstice. It reverts to zero declination when the Fall Equinox occurs and drops to a negative 23.5-degree declination during the Winter Solstice. This accompanying photos were taken by one of our viewers on the sky ride at Lake Compounce in Bristol last weekend. As you can see, the Sun's angle in the sky is still relatively quite high.

Today, for example, the declination of the Sun is an even 20 degrees North of the celestial equator. That's three-and-a-half degrees lower than where it was June 20. By the end of the month, it will be 18.5 degrees North of the celestial equator. The Sun's declination will be +14.15 degrees by August 15, and +8.52 on the final day of next month. By September 16, it will be just 3.16 degrees North of the celestial equator. As you can see, the Sun's angle will be dropping lower in the sky over the next two months.

The change in the Sun’s declination results in yearly cycles which are observed as each season progresses. The declination of the Sun has effects on its own altitude and to the duration of daylight. The Sun reaches its highest altitude above the horizon each day at noon in the Northern Hemisphere. With respect to the celestial equator, it reaches the highest altitude of 73.5 degrees the first day of the Summer, while its altitude reaches the minimum 26.5 degrees during the first day of Winter.

We'll see plenty of sunshine today, but it will be hot as temperatures climb close to 90 degrees. There is a chance of an isolated shower or thunderstorm as a cold front approaches from the Northwest. Tonight will be mostly clear and less humid with lows of 57 to 65 degrees. Tomorrow will be the best day of the week under sunny skies, lower humidity, and seasonable temperatures as highs reach the lower 80s. Unsettled weather is expected Thursday through Sunday.

Paul

Today Marks 43rd Anniversary of Apollo 11 Moon Landing

Some dates naturally carry more significance than others. Birthdays and anniversaries come to mind instantly. One such "anniversary" happened 43 years ago today. Those of you old enough to remember Sunday, July 20, 1969, no doubt can recall watching Apollo 11 astronaut Neil Armstrong descending the steps of the lunar module’s ladder and setting foot on the Moon for the first time. I was mesmerized by what I saw that night on the black-and-white Zenith television set in our living room.

Apollo 11, the fifth human spaceflight of the Apollo program, launched from the Kennedy Space Center four days earlier. As a young child of 10, watching Armstrong walk on the lunar surface was probably the most significant news event of my youth. I can still remember the late Walter Cronkite on CBS television describing the landing, and the bundle of nerves I felt for myself and the Apollo astronauts, Commander Neil Armstrong, Lunar Module Pilot Edwin “Buzz” Aldrin, and Command Module Pilot Michael Collins.

I was fascinated by the space program in the 1960s. Naturally, I couldn’t wait for the landing of Apollo on the Moon. As I recall, while on the far side of the Moon, the lunar module, called the Eagle, separated from the Command Module, named Columbia. Collins remained alone in Columbia, while Armstrong and Aldrin used Eagle’s descent engine to right themselves and descend to the lunar surface. The wait seemed interminable for this youngster, who couldn’t believe that we would actually see LIVE images from the Moon later that night.

I kept asking questions of my Mom and Dad all day and evening. “What will it look like on television?” “When will the astronauts climb out of the Eagle?” “How are we able to see it if they’re so far away?” They couldn’t answer most of my questions since this had never happened before. I still couldn’t believe what we were about to see. I’m sure it’s what ultimately piqued my interest in astronomy, subsequent space missions, and Science in general. This is what it looked like 43 years ago today.



Our family gathered in the living room in front of the small TV set with rabbit ears and watched as Cronkite prepared us for the first step on the Moon. Just over six-and-a half hours after Apollo 11 landed on the Moon at 4:17 p.m., we sat in silence and awe as Armstrong made his descent to the Moon’s surface at 10:56 p.m. and spoke his famous words: “That’s one small step for man, one giant leap for mankind.”

I don't know if there will be any mention of it on any newscasts today. Three years ago, however, it was a different story as it marked the 40th anniversary of that unforgettable day. Incredibly, more than half the people living in the United States today weren’t even born when Neil Armstrong became the first man to walk on the moon. It was arguably the most historic event of the 20th century. I, for one, am glad I saw it LIVE, and I will never forget it for the rest of my life!

Paul

Second Official Heat Wave of the Season Broken

The second official heat wave across southwestern Connecticut since June 1 is over, but not before a record high temperature was established Wednesday afternoon at Sikorsky Memorial Airport in Stratford. The mercury hit 95 degrees yesterday at 1:42 p.m., officially tying the previous mark which was established in 2006. Consider the normal high temperature for this time of the year is 83 degrees.

A strong cold front approached the region early yesterday afternoon, triggering a round of showers and thunderstorms just before 3 o'clock. Viewer Ralph Fato of Norwalk sent this unique photo to me. He wrote, "I took this picture before the line (of storms) came through and matched it with the satellite and radar photo at the time." This is unique. The radar clearly shows the approaching storms to the Northwest, and the photo shows the darkening clouds in advance of the storms. Click the photo to see a larger version.

We've had high temperatures of at least 90 degrees six times or one-third of July. The latest heat wave featured high temperatures of 91, 93, and 95 degrees Monday through Wednesday, respectively. Since June 1, we've had 10 90+ degree days at the airport which, more often than not is cooler than inland communities due to a mild sea breeze this time of the year. The average temperature thus far this month is 79.6 degrees, which is a healthy 5.8 degrees above normal. Take a look at the following graph provided by Ralph Fato.

A closer look at the weather record book reveals that we just barely missed two more official heat waves by just one degree each time. We missed a heat wave June 20 (92), June 21 (96), and June 22 (89) by one degree, and another potential heat wave was nixed by only one degree July 5 (91), July 6 (89), and July 7 (93). The first heat wave happened June 29 (91), June 30 (92), and July 1 (92).

Although cooler and less humid air has arrived this morning, we're not out of the woods as far as precipitation is concerned. The frontal boundary which pushed through the region has stalled just to our South, and that may trigger a shower or two this afternoon. We'll be on the northern edge of a wave of low pressure later tonight and tomorrow, and that will bring occasional rain and much cooler air. Tomorrow's high will only reach the low-to-mid 70s. A nicer weekend is ahead, however.

Paul

Severe Weather Potential for Wednesday

The second of three consecutive hot and humid days is sending many southwestern Connecticut families to lakes, beaches, and close to the air conditioners this afternoon. Today will most likely be the hottest day of the week after the mercury reached 91 degrees at Sikorsky Memorial Airport in Stratford Monday afternoon. The normal high temperature for this time of the year is 83 degrees, and the record high is 95 set in 1953.

The Connecticut Department of Energy and Environmental Protection has issued an Air Quality Alert, which will remain in effect through 11 o'clock tonight. A southwest flow of air is bringing tropical moisture, high humidity, and hot surface temperatures to the region. This will create a favorable environment for ozone levels to exceed the threshold for 'unhealthy for sensitive groups.'

However, our weather picture is about to change in a big way. A cold front will approach from the North tomorrow afternoon, bringing the potential for strong-to-severe thunderstorms to the region. The forecast surface map below shows the cold front just to the North and West of southwestern Connecticut at 8 o'clock Wednesday evening. There is concern for the possibility of vivid lightning, heavy rain, small hail, and gusty winds. 

The atmosphere will be saturated. Working in our favor, though, are winds less than 50 knots in the upper atmosphere and the influence of the maritime air ahead of the front. Keep an eye to the sky tomorrow afternoon. Not surprisingly, the National Weather Service Storm Prediction Center has placed our region in a slight threat for strong convection during the day tomorrow.

The silver lining behind the front will be much more comfortable and seasonable weather by the end of the week and the weekend. One of the computer models is hinting at some moisture making its way toward Southern New England Friday, but we're playing optimist in the weathercenter and expecting a large dome of high pressure to keep us bright and dry through Sunday.

Paul