TEMPERATURE SUMMARY...

In December, temperatures were below average across Vermont and northern New York. Warmer than average temperatures opened the month (in the upper 50s), but a significant cold front pushed across the region in the first week of December, which sent temperatures plummeting to at or below zero by the 10th. This was followed by a period of above-average temperatures (into the 40s) by December 12th-13th, but temperatures returned to average as a cold front moved through on the 14th. Temperatures stayed around normal for the next week, to be followed by a period of below average temperatures between the 24th-28th. By the end of the month, temperatures would moderate again, reaching into the 40s.

TEMPERATURE STATISTICS ACROSS THE NORTH COUNTRY FOR THE MONTH OF DECEMBER...

	Burlington	Montpelier	Massena	Saint Johnsbury
Avg. Temp	23.5	20.9	22.6	21.2
Departure	-1.3	-1.6	+0.9	-1.2
Highest	57 on 1st	50 on 1st, 13th	63 on 1st	54 on 13th
Lowest	0 on 10th	-4 on 10th	-9 on 10th	-1 on 10th

Below are daily temperature graphs for the month of December for Burlington, Montpelier, Massena, and Saint Johnsbury.

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PRECIPITATION SUMMARY...

Through December, liquid-equivalent precipitation anomalies showed large variability. Generally, liquid-equivalent precipitation amounts were lowest across the St. Lawrence Valley, the northern Adirondacks, the northern Champlain Valley, and in some of the east-facing slopes of the Green Mountains. The largest totals were generally located across the west-facing slopes of the Green and Adirondack Mountains. The heaviest snowfall during the month of was found largely over the northern Greens and parts of the Northeast Kingdom. Another relative maximum in snow totals was located across the Adirondacks. Elsewhere, snowfall totals between 1 and 2 feet were common for most locations in Vermont and northern New York.

PRECIPITATION STATISTICS ACROSS THE NORTH COUNTRY FOR THE MONTH OF DECEMBER...

	Burlington	Montpelier	Massena	Saint Johnsbury
Monthly Total "	3.60	1.52	1.57	3.04
Departure	1.38	-1.09	-1.37	0.04
Greatest 24hr	1.30 on 12th-13th	0.92 on 1st-2nd	0.95 on 1st	1.12 on 1st-2nd
SNOW/SLEET
Monthly Total "	27.9
Greatest 24hr	4.1

BURLINGTON FORECAST AREA ACCUMULATED MONTHLY PRECIPITATION (IN INCHES) FOR THE MONTH OF DECEMBER

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BURLINGTON FORECAST AREA ACCUMULATED MONTHLY SNOWFALL (IN INCHES) FOR THE MONTH OF DECEMBER

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MONTHLY WEATHER PATTERNS AND GLOBAL CLIMATE DRIVERS...

The 500 MB anomaly pattern for December showed upper-level riding (indicated by warmer colors in Figure 7) across the North Pacific, northern Canada and across Greenland, with lower than average geopotential heights (colder colors in Figure 7) across the eastern U.S. and the north-central Atlantic Ocean. The Arctic Oscillation (AO), one of the major modes of wintertime climate variability across the Northern Hemisphere, turned highly negative during the latter part of December. Negative AO values often result in similar 500 MB anomaly patterns as shown in Figure 7. Atmospheric circulation patterns often associated with negative AO values include a "blocking pattern" in the higher latitudes of the northern Atlantic Ocean (reflected in the warmer colors, e.g. strong upper-level ridging, over northeast Canada and Greenland in Figure 7). Negative AO patterns can result in unusual winter weather across the Southeast. An atypical winter storm affected parts of the southeast around the Christmas holiday, and would then make its way up the mid-Atlantic and Northeast.

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