Daily variability in weather is great, but the annual variance in temperature and precipitation is slight. The length of the growing season ranges from less than 100 days above the 2,000 ft elevation, and in some deeper cold hollows of northern Vermont and New Hampshire, to more than 150 days in southernmost New Hampshire, northern Massachusetts, the upper Hudson Valley of New York, and a small portion of the northern Champlain Valley. The interaction between the rugged topography and prevailing westerly flow across it gives rise to a complex but orderly distribution of precipitation. A fair amount of this falls as snow. The flow around these systems pulls inland vast amounts of moist air from the Atlantic Ocean.
Heavy precipitation is the result.
The full brunt of these storms is felt most often in southern Vermont, northern Massachusetts, and New Hampshire from the Presidential Range southward. The high peaks of that range blunt the fury of such disturbances for locations further north and west, but substantial precipitation may fall over northern Vermont and the Eastern Townships of Quebec. Further to the north and west, increasing distance from the storm centers corresponds to a reduction in storm total precipitation and severity.