December 2012 Climate Report

December 2012 Climate Report for Puerto Rico and the U.S. Virgin Islands

December 2012 Highlights

New Records for December 2012

Date	New Record	Previous Record
December 2012	December 2012 ended as the ninth warmest December on record with an average temperature of 79.4°F.	December 1980 ended as the warmest December on record with an average temperature of 80.7°F.

Saint Croix

Date	New Record	Previous Record
December 08th	A record high temperature of 88°F.	This tied the previous record of 88°F set back in 2009, 1997, 1993 and 1963.
December 09th	A record high temperature of 88°F.	This tied the previous record of 88°F set back in 2002, 1997 and 1986.
December 12th	A record high temperature of 88°F.	This tied the previous record of 88°F set back in 1995, 1985, 1980 and 1963.
December 16th	A record low temperature of 67°F.	This broke the previous record of 69°F set back in 1980, 1964 and 1962.

December 2012 Statistics

Average December Temperatures/Precipitation (NCDC 1981-2010 averages):

	San Juan	Saint Thomas	Saint Croix
High	83.9°F	85.6°F	84.7°F
Low	73.4°F	73.5°F	73.4°F
Avg. T	78.7°F	79.5°F	79.0°F
Pcpn.	5.02’’	2.96’’	2.97’’

December 2012 Observations:

	San Juan	Saint Thomas	Saint Croix
High	84.7°F(+0.8°F)	84.1°F(-1.5°F)	85.3°F(+0.6°F)
Low	74.1°F(+0.7°F)	74.0°F(+0.5°F)	72.4°F(-1.0°F)
Avg. T	79.4°F(+0.7°F)	79.0°F(-0.5°F)	78.9°F(-0.1°F)
Pcpn.	5.31" (+0.29")	2.34"(-0.62")	2.18"(-0.79")

December 2012 extremes:

	San Juan	Saint Thomas	Saint Croix
High	87°F December 27th, 12th and 09th	86°F December 28th, 12th and 09th	88°F December 12th, 09th and 08th
Low	71°F December 16th	70°F December 30th	65°F December 15th

Rainfall Accumulations Year to Date (YTD)

Figure A – Graphical Display of precipitation for December 2012 across Puerto Rico and the U.S. Virgin Islands derived from a combination of rain gage and radar data.

Figure B – Graphical Display of annual precipitation across Puerto Rico and the U.S. Virgin Islands derived from a combination of rain gage and radar data.

Figure C – Graphical display of departure from normal precipitation during 2012.

December Historical Statistics

Highest December Temperatures on record:

San Juan	Saint Thomas	Saint Croix
94°F December 6th 1989	92°F December 26th 1995	92°F December 27th 1995
91°F December 24th 1995	92°F December 25th 1995	90°F December 10th 1998
91°F December 26th 1994	90°F December 11th 1995	90°F December 29th 1972

Lowest December Temperatures on record:

San Juan	Saint Thomas	Saint Croix
62°F December 29th 1917	62°F December 5th 1942	61°F December 29th 1982
63°F December 22nd 1964	63°F December 24th 1991	61°F December 24th 1964
63°F December 30th 1917	63°F December 27th 1972	62°F December 28th 1980

Wettest Decembers:

San Juan	Saint Thomas	Saint Croix
16.81" 1981	9.87" 1960	14.03" 1960
15.40" 1910	7.45" 1963	9.07" 1975
12.64" 1922	6.66" 1981	7.86" 2001

Driest Decembers:

San Juan	Saint Thomas	Saint Croix
0.63" 1963	0.63" 1963	0.37" 2010
0.98" 1925	0.76" 1956	0.75" 2008
1.02" 1997	1.12" 2000	0.79" 1963

Decadal December Observations for San Juan, Puerto Rico

	2010-2012	2000’s	1990’s	1980’s	1970’s	1960’s
High	83.3°F	83.8°F	84.4°F	84.5°F	83.7°F	83.3°F
Low	73.2°F	72.8°F	72.5°F	72.4°F	73.3°F	71.1°F
Avg. T	78.2°F	78.3°F	78.5°F	78.4°F	78.5°F	77.2°F
Pcpn.	6.99"	5.19’’	4.08’’	5.36’’	4.57’’	4.54’’

Looking ahead toward the month of January

Average January Temperatures/Precipitation (NCDC 1981-2010 averages):

	San Juan	Saint Thomas	Saint Croix
High	83.2°F	85.1°F	84.0°F
Low	72.0°F	72.5°F	72.4°F
Avg. T	77.6°F	78.8°F	78.2°F
Pcpn.	3.76’’	2.38’’	2.14’’

Moon/Sun/Tide data for the month of January 2013

Sunrise/sunset data, phase of the moon, as well as tide data can all be found by going to the climate portion of the National Weather Service San Juan Climate homepage and then clicking on the astronomical tab.

National Weather Service Weather Forecast Office