Q: Why is it so cloudy in Central New York?
A: There are several reasons for this. First off, we are on the western slope of the Appalachian Mountains, which essentially run from Georgia, up the east coast, through Maine. Since the prevailing winds come from the west, the air is forced to rise up when it hits the higher terrain to our east. This causes the air to cool and the moisture to condense, thus forming clouds. We also have a large moisture source less than 100 miles away (Lake Ontario) which adds additional moisture to the air, especially from October to April. In addition to that our hills and mountains can sometimes trap moisture and cool air near the ground in the valleys.

Q: Why is there so much fog, especially in the fall?
A: The longer nights of the late summer and fall in combination with the clear skies and light winds that are common at night in August, September, and October, help temperatures to fall quickly to the dewpoint, the temperature at which water vapor in the air will condense. Once the temperature and dewpoint are the same, you can initiate the formation of fog. If there is still several hours before sunrise when the fog forms and the clear skies and light winds persist, the fog can become very dense, with visibility dropping to zero in spots. Our lakes and rivers, which are warm during that time of year, add additional moisture, and thus adds to the fog. The fog is most common in the valleys, particularly south of Route 20. The valleys of Otsego, Chenango, Madison, and Delaware counties are deep and narrow. These areas cool quickly and have rivers in the valleys, both helping to make fog quickly. The valleys south of Route 20 are among the foggiest in the country, with fog observed over 100 days a year on the average.

Q: Why does it snow so much in Central New York?
A: There are several reasons for this. The number one reason for this is our proximity to Lake Ontario, thus putting our area in line for "lake effect snow" which can generate significant amounts of snow. The second reason is our proximity to several major storm tracks. We are close enough to the coast to receive heavy snow from coastal storms (often referred to as Nor'easters), we are also close to the track of storms that go up the St. Lawrence River Valley, and also the storms that track through the Ohio Valley, Pennsylvania, then off the New England/Long Island coast. Finally, we are also usually in the path of "Alberta Clippers", storm systems that come from Alberta Province, Canada, then move quickly across the Great Lakes and Northeast U.S. These systems are actually quite strong but usually only bring a few inches of snow. This because of two reasons: 1) They move very fast and 2) It is coming from a part of the continent which there is little or no mositure to draw from (No major moisture sources like the Gulf of Mexico, etc.)

Q: Why does it get so humid sometimes in the summer?
A: While we do not see the oppressively humid conditions through the whole summer, we do see it from time to time. The humidity (moisture) comes more from the Gulf of Mexico and the Atlantic Ocean (off the Southeast Coast of the U.S.) than from the Great Lakes. We often refer to the "Bermuda High", the areas of high pressure that sits off the Atlantic Coast, near Bermuda. Winds flow around a high pressure clockwise in the Northern Hemisphere, therefore, it send a south to southwest wind into Central NY. This brings not just the heat, but especially the humidity from the Atlantic, and from the Gulf of Mexico.

Q: Why don't we see the sun much in the winter?
A: You can blame the lack of sun on several things. Obviously the lake effect clouds and snow, along with being near so many storm tracks, are key factors. One thing many people don't think about is the angle of the sun. The sun is at a low angle from November to February (only 23 to 37 degrees above the horizon) and has significantly less heating power than in the summer. The sun causes a process that we call in Meteorology, "mixing", when the sun heats the ground and creates vertical air movement from the surface to around 1 mile above the ground. When there is less "mixing", you cannot mix the low level moisture easily with the drier air that is above the ground, and create breaks in the clouds. In the wintertime you have to physically move the moisture out of our area, horizontally, by a change in the wind direction. Therefore the low clouds or "Battleship Gray Skies" we sometimes refer to, tend to stay around here longer. In the warmer months, when the sun is stronger and higher in the sky, the sun can partially or almost totally break up the clouds.

Q: Why does the weather change so much over such a small area?
A: All of the factors that have been discussed above in previous questions: The proximity to Lake Ontario, the hills and valleys, and how they are set up, contribute to the unique weather of Central New York. The biggest factor is our terrain. Which direction the hills and valleys face, whether there are forests or open fields near you, contribute significantly to the weather you see in your backyard.