Though its latitude is just over 45 degrees north, about the same as Portland, Oregon, the climate is considerably different from that of comparable lattitudes on the Pacific coast. The prevailing directions of air movements in north temperate latitudes bring about a strong continental influence rather than the maratime influence of the other side of the continent. The climate of our region is characterized by warm summers and cold, snowy winters. Summers are rarely as hot as more southerly regions. A ninety-degree day is relatively rare, happening in little more than half of the years. The hot days can occur anytime between April and October.
Precipitation averages around 40 inches per year roughly equally divided across all seasons. Winter precipitation falls mostly in the form of snow, though rain, sleet, and freezing rain also fall in virtually all winters.
The area lies far enough inland that the moderating effect of the ocean is diminished. Winter temperatures are generally 3 to 8 degrees colder than coastal areas, and snowfall is nearly double that of the immediate coast and the near islands.
The joke about the New England climate being 9 months of winter and 3 months of poor sledding is an old one. Some years it isn’t even true. Other jokes would have the seasons of Maine as: almost winter, winter, still winter, and construction.
There really are more than four seasons if we want to take in the fine distinctions of seasonal change. Winter might be said to coincide with the usual occurance of a permanent snow cover, in this area generally December until mid April. After that comes mud season. That is generally April. Then comes leafout when the trees go from nearly bare to almost fully leaved. In this area, May pretty much coincides with leafout. Then comes summer. That should be considered as lasting from June until mid September. Then comes the fall color season. That is from mid September until near the end of October. November and sometimes part or most of December is a brown, dreary time with neither leaves to rustle and sparkle or snow to cover the mud and add tang to the air and crunch to the paths. Most of hunting season occurs during this time as well, though it spreads a bit in both directions. Then we’re back to winter where we started.
Winter is cold and snowy, and the wind can blow. Sheltered valleys don’t see much of the wind, but can experience temperature extremes lower than that of uplands. After all, warm air rises and cold air sinks. If it is 10 below zero farenheit on the upper slopes of the valley, it might be 20 or even 25 below down in the river bottom. These extreme differences occur during still nights when there is no wind to mix up the air masses.
Animals in the region have each their own strategies for coping. Many birds cope by just packing up and leaving. Many humans have also adopted this strategy. Avian examples include the wood warblers, the wrens, and others. Some species are partially migratory. That is, some migrate while others stay put. Red breasted nuthatch is an example.
Other birds gather in flocks near reliable food sources. Evening grosbeaks, Robins, most blackbirds, and a few others are flocking birds. Some travel in loose groups looking for food. Chickadees, nuthatches, golden-crowned kinglets, goldfinches, and some others are found in such flocks.
Some animals hibernate. Porcupines, skunks, flying squirrels, and some smaller mammals do so as does as large a mammal as the black bear. Others, such as deer, form their own herds near food. A few animals of all types seem little inconvenienced by winter and go about their business as though nothing were happening. Maybe they are in denial. Reptiles and amphibians sleep out the winter, and insect populations either hibernate or overwinter as eggs or other pre-adult development stages.
During most years, the ground freezes before the permanent snow comes. When this occurs, walking in the woods can be easy and fun with the snow firm on a hard surface. When it doesn’t happen, a walk in the woods can quickly degenerate into a wallow.
There are really two mud seasons. The major one falls in the spring when the ground thaws, and the snow melts, but before the spring sun can dry out the surface layers. Mud season can begin in March and last until May, depending upon the season’s precipitation and temperature. Generally, though, if you think of April, think of mud. It can get so deep on back roads that school busses cannot traverse it. It is probably only rumor that an occasional sports car disappears completely beneath the gooey surface.
There is a secondary mud season some falls. It comes between the warm summer days when the sun evaporates the moisture and the freezup of the surface soil. Mud season generally means spring, though. During this time hibernating mammals begin to wake up and migrant birds start to straggle back. Phoebes are some of the first which is very nice because it is at this time that the insects start to wake up, some of the first being blackflies. These things bite. It is not true that the blackfly is the state bird of Maine. I think the phoebe should be the state bird because they show up just in time to start eating the pesky things. You have to like any bird that eats flying insects. Of course, chickadees, the actual state bird, do eat a few biting insects themselves.
Leafout is pretty much a May phenomenon here. The mud has usually pretty well dried, but there is little green showing on the deciduous trees at the beginning of that month. A few plants have flowered, but not many. Such domestic plants as crocus have been at it for awhile in places where the ground is clear of snow. More insects put in an appearance, including mosquitos. The only ones glad to see them are the birds that eat them. Most migrants return during this time, often to limited food supplies. It is a mystery of migration that the birds leave when food supplies are abundant and return when they are quite limited. Except for blackflies and mosquitos.
The first leaves are the maples. Then quaking aspens are early leafers also. Later are their close relatives, the big toothed aspens. Possibly the last of the trees to leaf out are the black locusts. These trees are not native to the region, but have become established here, especially along road cuts with other species of locust, and do reasonably well.
Summer is usually pleasantly warm. Actually, that’s the average, but the averages are made up of lots of extremes. The daily high for July averages in the mid 70s, but there will be lots of days in the 80s with high humidity and an occasional day in the 90s. There will also be days in the 60s and an occasional day in the 50s. These colder days are usually overcast, windy, and foggy or rainy. Of course, on the warm days there are bugs.
Still, the summers are fairly pleasant here. Birds are nesting now, and getting on with the business of raising their young. The search for food keeps them fully occupied.
Contrary to popular belief, the intensity of fall colors is most dependent upon nutrients available to the plants during the growing season. Fall temperatures are much less important. The foliage season peaks in our area about the first week of October and the most common critter is often the ‘leaf peeper’. The birds have generally finished their family duties and are either fattening up for the trip south or have already gone. Some will have been gone for a month or more when the leaves change.
The temperatures are cooling down considerably. September averages 10 degrees cooler than July and there can be frost before the end of the month. In October the nights can be downright cold. It is a rare October that doesn’t have a few instances of freezing temperatures. In fact, by the end of the month, the average overnight temperature is right at the freezing mark.
By that time the leaves are gone as are most of the tourists. Some specialized hunting has started, so it is wise to wear blaze orange colors in the woods.
The days and nights are growing colder. There are no leaves on the trees to contrast with the barren brownness — or to slow down the wind. The ground starts to freeze up in alternating freezes and thaws. Most of the migrant birds have gone. The flocks have formed around feeding areas. Hunting season is at its height. The thoughts of many others turn to fires and music and books. For a few thoughts are of warmer regions farther south. That species of snowbird, though, has generally already migrated along with the feathered types. And then comes the snow, and winter.
Temperature extremes range from about (all in farenheit) 95 to around minus 30. In some of the colder valleys minus 40 will occur. These extremes do not occur when the wind is blowing because that causes mixing of air masses, but it can still be cold when the wind is blowing. Windchill temperatures represent the actual chilling capacity of the air and minus 40 is not uncommon. That means that the combination of wind and temperature makes it feel like minus 40. That’s cold. The average monthly highs, lows, and averages for the center are (highs are first, then lows, then daily averages which are halfway between highs and lows):
- January 24 5 15
- February 29 8 19
- March 39 19 29
- April 51 30 41
- May 64 42 53
- June 72 52 62
- July 77 57 67
- August 76 56 66
- September 67 47 57
- October 56 36 46
- November 43 26 35
- December 30 12 21
Here are the record temperatures for the area. The column to the right of the month is the record low; the next column is the record high. Notice that sub zero temperatures can be expected as late as March. Most years there are two or three such extremes in that month. Note also that 90 degree temperatures can occur as early as April or as late as September. Extremes that early or late are rare, though.:
- January -27 57
- February -26 58
- March -16 73
- April 5 92
- May 25 94
- June 34 94
- July 41 95
- August 39 93
- September 26 90
- October 18 80
- November -5 71
- December -27 61
The first frost is usually in late September (in the valleys) or early October. Sub-zero temperatures do not generally occur until December, though they have been recorded in November. In January, one third to one half of the nights register sub-zero temperatures, but by the time March rolls around, the number is down to two or three. Double-digit sub-zero is recorded fairly regularly in March, but not every year. Double-digit sub zero is registered in January and February almost every year, and quite frequently in December.
Snowfall totals range between 80 and 140 inches in typical years with the average being about 105 inches. The permanent snow cover lasts from November or December into April. Rarely is the ground completely bare in January, February, or March. The maximum depth usually occurs in February or early March and can be anywhere from 2 and one half feet to 4 and a half feet or even more on rare occasions. In February, occasional warm days and cold nights start sap moving, and most maple syrup producers tap their trees at this time. In March, substantial snow falls, but warmer days steadily reduce the pack. This is the peak syruping time. By the time the tree buds swell toward spring, runs are diminished and the last runs can taste of the buds themselves and be less desirable.
Snowfall is destributed across the average season as follows:
- October 1 inch
- November 7 inches
- December 22 inches
- January 27 inches
- February 26 inches
- March 19 inches
- April 3 inches
The heavy snowfall assures the popularity of winter sports. There are no ski resorts in the immediate vicinity, but cross country skiing, snomobiling, and snowshoing are popular.
Precipitation averages are fairly steady across the year, but wide year-to-year variations occur. Averages range from a low of 2.65 inches in February to highs of 3.75 in June, September and November. Figures in the table below are in inches.
- January 3.60
- February 2.65
- March 3.46
- April 3.50
- May 3.60
- June 3.75
- July 3.40
- August 3.28
- September 3.75
- October 3.65
- November 3.75
- December 3.50
The area is cold and snowy in the winter, but it is not the coldest or snowiest region of North America or even of the United States. Minneapolis-St. Paul gets less than half our amount of snow, but is several degrees colder in the winter. And the twin cities are hotter in the summer, being fully under the continental influence. Syracuse has the reputation as the snowiest major city on the North American continent. Their snowfall totals average about 10 inches more than ours. But Syracuse is warmer. The January average is in the low to mid 20s, so there are occasional warm spells sufficient to melt the snow.
Washington, DC is a dozen degrees hotter in the summer and perhaps 20 degrees warmer in January. DC gets less than 20 per cent as much snow as we do. Miami is even hotter than Washington in the summer and perhaps 50 degrees warmer than we are in January. And guess how much snow they get? About the same amount as San Diego gets. None. The Pacific coast is warmer in all seasons except for spots in Northern California and part of Oregon that are under the influences of currents that keep summers cool. The coastal region is cooler in the summer than the interior and warmer in the winter. The maratime influence, again. Portland, Oregon, at about our lattitude gets little snow and has rarely recorded sub zero temperatures. We, on the other hand, have thirty to forty days per year with sub zero temperatures.
The interior regions of the continent have considerable variation between summer and winter. Where our variation is about 50 degrees, Minneapolis-St. Paul varies by over 60 degrees. This effect becomes less pronounced as you travel south. By the time you reach the Gulf coast, July averages are generally over 80 with day time highs in the 90s for months. January average highs are close to 60 with snow and freezing weather a rarity.
The Rocky Mountains are likely to have earlier and later snows than we have, but except for favored slopes, less total snow. Extreme temperatures are more frequent, but for most areas averages are milder than ours. Albuquerque averages 34 in January, 79 in July. Denver’s averages are 30 for January, 74 for July. Helena’s January is just slightly milder than ours at 20 degrees. July is just slightly warmer at 69.
Of course, if we want to compare with extremes, there are places in mountainous areas that average over 200, even over 300 inches of snow per year. Places in the high arctic and antarctic, on the other hand, may average less than 2 inches per year because they are so dry. Fairbanks averages minus 10 in January, 63 in July. Yellowknife, capital of Canada’s Northwest Territories, averages close to minus 20 in January. Places in Sibera average around minus 50. None of these places get as much snow as we do, but probably don’t need snow to remind the inhabitants that it is winter.