THE VERMONT WEATHER BOOK by David Ludlum (Vermont Historical Society, 1996)
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Though having fewer days by two or three, more inches of snow actually fall in February than in any other month, and the percentage of the total precipitation falling as snow reaches the highest figure of the year: 97 percent on the first day of the month, and 88 percent on the last day, according to a study of snowfall at Burlington.
The sun makes good progress northward during February. It climbs about nine degrees toward the zenith until on the 28th it stands at noontime about 37 degrees above the southern horizon. The period of direct sunlight is 71 minutes longer at the end than at the beginning of the month, and total insolation increases by 12.8 percent.
February is the stormiest month of the year in Vermont. The main jet stream crosses the Pacific Ocean along the latitude 35° N; when approaching the continent, it dips southeast over Baja California. After taking a southerly route across the country, the jet trends northeast to the Ohio Valley and is joined by a weaker westerly jet from the northern plains. The combined airflow leaves the continent in the vicinity of the Virginia capes. The southerly displacement of the cross-continent air movement contributes to storm formation (cyclogenesis) over the tropical Gulf of Mexico and Texas. During the winter season, storm centers from this region head northeast along either the western or eastern slopes of the Appalachian Mountains.
The path of the storm track determines what kind of weather will prevail over Vermont. If the storm centers pass to the west over Pennsylvania and western New York State, south and southeast airstreams will overspread Vermont with a steadily increasing warmth. Though the storm precipitation may begin as snow, the possibility of a change to ice pellets and eventually to rain increases with the continuation of the flow from the southerly quadrant of the compass. If the storm track stays to the east along the Atlantic coastal plain, precipitation will begin as snow and usually continue in that form, perhaps becoming heavy when the moisture of the nearby ocean is tapped by the circulation.
The major stormway from the Great Lakes down to the St. Lawrence Valley remains active, though less frequented than in the earlier winter months. Cyclonic systems moving to the north of Vermont come from relatively dry regions and are usually fast movers, so the period of precipitation is shorter and less intense than with Atlantic coastal storms.
The behavior of polar anticyclones continues the same as in January. The frozen surface of Hudson Bay and the snow-covered tundra of Central Canada condition the atmosphere for several days until the air masses move into the northeastern states on gusty winds. Occasionally, high-pressure areas of great magnitude build up in the Hudson Bay region. Known as Hudson Bay Highs, they await the passage of a cyclonic disturbance along the Atlantic seaboard before their frigid airstreams are enticed southeast into the rear of the departing storm system. They treat the Vermont countryside to its coldest weather, with the temperature dropping as much as 30 to 40 degrees to minimums of -20° or lower. The record cold of February 1934 resulted from a series of cold outbreaks from the Hudson Bay region following the passage of successive snowstorms along the coast.
In February, mean temperatures begin to respond to the increasing altitude of the sun. Newport in the northeast shows a rise of 2.3 degrees to 16.1°; Vernon in the southeast increases by 2.3 degrees to 22.5°. The highest readings obtain in the southwest: Bennington reaches a mean of 24.1°. The severest cold can occur as late as February 16, but thereafter comes a decline in the refrigerating ability of the Hudson Bay region. Temperatures in Vermont do not drop below -40° after mid-February. The worst of winter’s sting is over.
Total precipitation in the northeast and southeast sections averages slightly more each day than in January because of more plentiful Atlantic moisture. The west and northwest sections are the driest under the continued domination of the westerly airflow. Burlington receives only 1.68 inches in February, while Vernon has an expectancy of 3.09 inches. The mountain stations catch the maximum amounts; Searsburg Station, at a high elevation in Bennington County, averages 3.73 inches.
The highest February temperature reported in this century was 65° at Rutland in 1957 and the lowest, -46°, at East Barnet in 1943.
The second day of February marks a big event on the folklore calendar, a day thought to portend a possible end of wintry conditions since the Europeans regarded November, December, and January as the three winter months. Hibernating bears and badgers were supposed to come out of their lairs and check the weather prognostics. In America the role was transferred to the groundhog, or woodchuck, of which Vermont has an abundance. If it is sunny on February 2, the animal will see his shadow and be frightened into returning to his hibernation hole for six weeks longer, and winter will continue for that period. Since the percentage of possible sunshine is 46 percent at Burlington in February, the groundhog has about a fifty-fifty chance of seeing his shadow.
