August 2012 Climate Report

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

August 2012 and Summer 2012 Highlights

New Records

Date	New Record	Previous Record
Summer 2012 (Jun-Jul-Aug)	Summer 2012 ended as the third warmest summer on record with an average temperature of 84.3°F.	Summer 1980 ended as the warmest summer on record with an average temperature of 85.1°F.

Saint Thomas

Date	New Record	Previous Record
Summer 2012 (Jun-Jul-Aug)	Summer 2012 ended as the eleventh warmest summer on record with an average temperature of 83.6°F.	Summer 1994 ended as the warmest summer on record with an average temperature of 86.7°F.
Summer 2012 (Jun-Jul-Aug)	Summer 2012 ended as the eight driest summer on record with 5.96".	Summer 1994 ended as the driest summer on record with 3.74".

Saint Croix

Date	New Record	Previous Record
August 2012	August 2012 ended as the twelfth driest August on record with 2.27".	August 2005 ended as the driest August on record with 1.35".
Summer 2012 (Jun-Jul-Aug)	Summer 2012 ended as the fifth driest summer on record with 4.43".	Summer 1985 ended as the driest summer on record with 3.64".

August 2012 Statistics

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

	San Juan	Saint Thomas	Saint Croix
High	89.2°F	90.2°F	89.2°F
Low	78.2°F	78.2°F	78.4°F
Avg. T	83.7°F	84.2°F	83.8°F
Pcpn.	5.46’’	3.74’’	3.15’’

August 2012 Observations:

	San Juan	Saint Thomas	Saint Croix
High	88.9°F(-0.3°F)	88.6°F(-1.6°F)	89.8°F(+0.6°F)
Low	78.1°F(-0.1°F)	78.0°F(-0.2°F)	77.0°F(-1.4°F)
Avg. T	83.5°F(-0.2°F)	83.3°F(-0.9°F)	83.4°F(-0.9°F)
Pcpn.	7.48" (+2.02")	2.79" (-0.95")	2.27" (-0.88")

August 2012 extremes:

	San Juan	Saint Thomas	Saint Croix
High	93°F August 9th	92°F August 20th, 11th and 2nd	93°F August 11th and 2nd
Low	74°F August 13th and 12th	75°F August 24th	72°F August 24th

Monthly Summary

August 2012 began with Tropical Storm Ernesto. This system tracked south of Puerto Rico and U.S. Virgin Islands on August 3^rd and 4^th and left periods of showers and thunderstorms mainly over the southern slopes of the island. Afterward, a generally fair weather pattern prevailed, with limited convection across western Puerto Rico. By the end of the month, Tropical Storm Isaac tracked south of the area leaving hazardous sea across the Caribbean waters. The outer bands of Isaac left rainfall accumulations of 2 to 4 inches island-wide with isolated amounts between 6 and 8 inches across sectors of eastern and southern Puerto Rico during a four day period. Strong gusty winds were also reported with Isaac.

Rainfall Accumulations Year to Date (YTD)

Figure A – Graphical Display of precipitation for August 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 YTD 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 YTD.

August Historical Statistics

Highest August Temperatures on record:

San Juan	Saint Thomas	Saint Croix
97°F August 21st, 1980	99°F August 4th, 1994	95°F August 25th, 1999
96°F August 20th, 1980	99°F August 8th, 1979	95°F August 19th, 1972
96°F August 23rd, 1974	98°F August 13th, 1994	94°F August 4th, 1972

Lowest August Temperatures on record:

San Juan	Saint Thomas	Saint Croix
68°F August 12th, 1904	62°F August 2nd, 2001	63°F August 17th, 1978
69°F August 29th, 1916	64°F August 2nd, 1972	67°F August 31st, 1979
69°F August 7th, 1913	64°F August 1st, 1972	67°F August 16th, 1978

Wettest Augusts:

San Juan	Saint Thomas	Saint Croix
18.56" 2011	9.14" 2011	11.41" 1979
14.10" 1944	8.54" 1963	11.04" 1989
11.76" 1955	8.22" 2005	11.04" 1989

Driest Augusts:

San Juan	Saint Thomas	Saint Croix
1.53" 1919	0.70" 1993	1.35" 2005
1.83" 1994	0.98" 1991	1.40" 1980
1.93" 1982	1.26" 2002	1.51" 2009

Decadal August Observations for San Juan, Puerto Rico

	2010-2011	2000’s	1990’s	1980’s	1970’s	1960’s
High	88.8°F	89.0°F	89.4°F	89.9°F	88.3°F	87.8°F
Low	78.1°F	77.6°F	77.3°F	77.0°F	77.3°F	75.6°F
Avg. T	83.5°F	83.3°F	83.3°F	83.4°F	82.8°F	81.7°F
Pcpn.	11.48"	5.92’’	4.83’’	5.08’’	5.27’’	6.13’’

Looking ahead toward the month of September

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

	San Juan	Saint Thomas	Saint Croix
High	89.2°F	90.0°F	89.0°F
Low	77.8°F	77.9°F	77.3°F
Avg. T	83.5°F	84.0°F	83.1°F
Pcpn.	5.77’’	5.58’’	4.86’’

Moon/Sun/Tide Data for the month of September 2012

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.

Click here to return to NWS San Juan Local Climate Web Page

National Weather Service Weather Forecast Office