Supplemental June and January-June Information
- Climate Highlights — June
- The average temperature for the contiguous U.S. during June was 71.2°F, which is 2.0°F above the 20th century average. The June temperatures contributed to a record-warm first half of the year and the warmest 12-month period
the nation has experienced since record keeping began in 1895. Scorching
temperatures during the second half of the month led many cities to set
all-time temperature records.
- Precipitation totals across the country were mixed during June. The nation, as a whole, experienced its tenth driest June on record, with a nationally-averaged precipitation total of 2.27 inches, 0.62 inch below average. Record and near-record dry conditions were present across the Intermountain West, while Tropical Storm Debby dropped record precipitation across Florida.
- Warmer-than-average temperatures were anchored across the Intermountain West and much of the Great Plains during June. Colorado had its warmest June on record, with a statewide temperature 6.4°F above average. Seven additional states in the region had a top ten warm June.
- Cooler-than-average temperatures were present for the Pacific Northwest, where Washington had its seventh coolest June on record. Cooler-than-average conditions were also present for the Southeast, despite record warm temperatures towards the end of the month.
- Record-breaking temperatures occurred across a large portion of the nation during the second half of June. Over 170 all-time warm temperature records
were broken or tied during the month. Temperatures in South Carolina
(113°F) and Georgia (112°F) are currently under review by the U.S. State Climate Extremes Committee as possible all-time statewide temperature records.
- Precipitation patterns were mixed across the country. Drier-than-average conditions were present from the West, through the Plains, into the Ohio Valley and Mid-Atlantic. Wyoming had its driest June on record, with a precipitation total of 0.45 inch, which is 1.27 inches below average. Eleven additional states from Nevada to Kentucky had June precipitation totals ranking among their ten driest.
- According to the U.S. Drought Monitor,
as of July 3, 56.0 percent of the contiguous U.S. experienced drought
conditions, marking the largest percentage of the nation experiencing
drought conditions in the 12-year record of the U.S. Drought Monitor.
Drought conditions improved across Florida, due to the rains from
Tropical Storm Debby. Drought conditions worsened across much of the
West, Central Plains, and the Ohio Valley, causing significant impacts
on agriculture in those regions.
- Tropical Storm Debby brought copious precipitation to Florida during June as it slowly traversed the state. Florida's monthly statewide precipitation total
of 13.16 inches was 6.17 inches above average, ranking as the wettest
June on record for the state. Parts of the Northeast, as well as the
Pacific Northwest, were wetter than average. Maine, Oregon, and Washington each had a top ten wet June.
- Several large wildfires raged across the West in June, destroying
hundreds of homes and causing the evacuation of tens of thousands of
residences. The very dry, warm, and windy weather created ideal wildfire
conditions. Nationwide, wildfires scorched over 1.3 million acres, the
second most on record during June.
- A list of select June temperature and precipitation records can be found here.
- Climate Highlights — Year-to-Date (January-June)
- The January-June period
was the warmest first half of any year on record for the contiguous
United States. The national temperature of 52.9°F was 4.5°F above
average. Most of the contiguous U.S. was record and near-record warm for the six-month period, except the Pacific Northwest. Twenty-eight states east of the Rockies were record warm and an additional 15 states were top ten warm.
- The first six months of 2012 were also drier than average for much of the contiguous U.S., with a nationally-averaged precipitation total 1.62 inches below average. Drier-than-average conditions stretched from the West, through the Central Plains, into the Ohio Valley and Mid-Atlantic. Fourteen states in total had precipitation totals for the six-month period among their ten driest.
- Wetter-than-average conditions were present for the Northwest and Upper Midwest, where Minnesota, Oregon, and Washington had six-month precipitation totals among their ten wettest.
- The U.S. Climate Extremes Index (USCEI),
an index that tracks the highest and lowest 10 percent of extremes in
temperature, precipitation, drought and tropical cyclones across the
contiguous U.S., was a record-large 44 percent during the January-June
period, over twice the average value. Extremes in warm daytime
temperatures (83 percent) and warm nighttime temperatures (70 percent)
covered large areas of the nation, contributing to the record high
- Climate Highlights — 12-month period (July 2011-June 2012)
- The July 2011-June 2012 period
was the warmest 12-month period of any 12-months on record for the
contiguous U.S., narrowly surpassing the record broken last month for
the June 2011-May 2012 period by 0.05°F. The nationally-averaged temperature of 56.0°F was 3.2°F above the long term average. Every state across the contiguous U.S. had warmer than average temperatures for the period, except Washington, which was near normal.
Alaska Temperature and Precipitation:
had its 41st coolest June since records began in 1918, with a temperature 0.2°F (0.1°C) below the 1971–2000 average.
had its 41st warmest April-June since records began in 1918, with a temperature near the 1971–2000 average.
had its 16th coolest January-June since records began in 1918, with a temperature 2.7 °F (1.5°C) below the 1971–2000 average.
had its 20th wettest June since records began in 1918, with an anomaly that was 12.4 percent above the 1971–2000 average.
had its 29th wettest April-June since records began in 1918, with an anomaly that was 8.2 percent above the 1971–2000 average.
had its 33rd wettest January-June since records began in 1918, with an anomaly that was 11.1 percent above the 1971–2000 average.