National Overview - September 2006


NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. This was coincident with the release of the February 2014 monthly monitoring report. For details on this transition, please visit our public FTP site and our U.S. Climate Divisional Database site.

Maps and Graphics:


September Most Recent 3 Months Most Recent 6 Months
Most Recent 12 Months Year-to-Date US Percent Area Very Wet/Dry/Warm/Cold
Annual Summary for 2005

PLEASE NOTE: All temperature and precipitation ranks and values are based on preliminary data.  The ranks will change when the final data are processed, but will not be replaced on these pages.  Graphics based on final data are available on the Climate Monitoring Products page.


For graphics covering periods other than those mentioned above or for tables of national, regional, and statewide data from 1895-present, for September, last 3 months or other periods, please go to the Climate At A Glance page.
[------- visual page separator -------]

National Overview:


September
  • 31st coolest September on record (1895-2006). (Most recent below average monthly U.S. temperature: August 2004 - 5th coolest on record)
  • 7th coldest September for the Southwest Region
  • Only 5 states above normal temperatures in September: Washington, Oregon, Idaho, Montana and Vermont
  • 37th wettest September for U.S.
  • Wettest September on record for Kentucky
  • South Dakota ranked 6th wettest September
  • Regionally, wet in Southwest, West North Central, Central and Northeast
  • For information on local temperature and precipitation records during the month, please visit NCDC's Extremes page.


  • Drought conditions persisted in the South and northern Plains, with exceptional drought continuing in parts of northeast Texas.  For more information on drought during September, please visit the U.S. Drought page.

  • Four hurricanes (Florence, Gordon, Helene and Isaac) developed in the Atlantic Basin in September. Florence impacted the island of Bermuda as a Category 1 storm.
  • In the East North Pacific Basin, Hurricane Lane made landfall in Mexico as a Category 3 storm.
  • El Niño-Southern Oscillation (ENSO) conditions began a transition to a warm phase (El Niño) in the tropical Pacific basin by the end of August. During the first half of September, El Niño conditions developed as the SSTs and oceanic heat content increased rapidly since the beginning of the month. For more information on ENSO conditions, please visit the NCDC ENSO Monitoring page and the latest NOAA ENSO Advisory.
For additional details, see the Monthly and Seasonal Highlights section below and visit the September Climate Summary page. For details and graphics on weather events across the U.S. and the globe please visit NCDC's Global Hazards page.
[------- visual page separator -------]

Monthly and Seasonal Highlights:


National:

For additional national, regional, and statewide data and graphics from 1895-present, for September, the last 3 months or other periods, please visit the Climate At A Glance page.
  • September 2006 was the 31st coolest September in the 1895-2006 record.  The preliminary nationally averaged temperature was 64.7°F (18.2°C).

  • September had above-average precipitation nationally, ranking as the 37th wettest September in the 1895-2006 record.  An average of 2.68 inches (68 mm) fell over the contiguous U.S. in September, 0.2 inches (5 mm) above the 20th century mean for the month.

  • The 3-month period (July-September) was the 12th warmest in the 1895-to-present record.  The preliminary nationally averaged July-September temperature was 72.1°F (22.3°C).  The warmest July-September period on record occurred in 1998 (73.5°F or 23.1°C). A total of 8.23 inches (208 mm) of precipitation fell during this 3-month period, which corresponds to a ranking of 32nd wettest.

  • The 6-month (April-September) national average temperature was the warmest such period on record. The nationally-averaged temperature was 67.9°F (20°C).  At 15.56 inches (393 mm), April - September precipitation was below-normal and ranked as the 40th driest such period in the 1895-2006 record.

  • January to September has been the warmest such year-to-date period on record.  The nationally averaged year-to-date temperature was 58.3°F (14.6°C). The previous record of 58.2°F (14.6°C) was set in 2000.  The year-to-date period was the 29th driest January-September in the 112-year record, receiving a national average of 21.72 inches (548 mm) of precipitation during the period, or 1.0 inches (24 mm) below the 20th Century average.

  • October 2005 - September 2006 was the 2nd warmest such period in the 1895-2006 record.  The preliminary nationally-averaged 12-month temperature was 55.1°F (12.8°C).  Precipitation was below-average for the October 2005 - September 2006 period, ranking it as the 37th driest October-September in the 111-year record.  The nationally-averaged 12-month precipitation accumulation was 28.40 inches (717 mm).

Regional and Statewide:
  • July-September precipitation across New Mexico was 2nd wettest on record, 3rd wettest in Kentucky. Much above average temperatures existed in the West, Pacific Northwest and the Northern Plains states. Below average temperatures existed across Colorado and New Mexico.

  • The July-September regional temperatures were 3rd warmest on record for the West. Much above average temperatures existed in the Northwest and West North Central regions. In the Southwest, precipitation was 4th wettest in the last 112 years.

  • The past 6-months (April-September) were above- to much-above-normal over all regions of the contiguous United States, with the West having its 2nd warmest such period on record. The Northwest and West North Central regions were 3rd warmest.
  • April - September temperature was much above normal across much of the western half of the contiguous U.S. Wyoming was warmest on record for this period. North Dakota, Nevada and Louisiana were each 2nd warmest. Twenty-nine states were either record warmest and/or had much above average temperatures during the April to September period. Rhode Island was wettest on record during this period and precipitation received in Vermont, New Hampshire and Massachusetts was 2nd wettest.

  • The Year-to-Date period (January-September) was record warm in Montana and 2nd warmest in four additional states (North and South Dakota, Nebraska and Oklahoma).  No state was near or cooler than average for the period. Eight states (Indiana, Michigan, New York, Vermont, New Hampshire, Massachusetts, Connecticut and Rhode Island) were among the top 10 wettest during this period.

  • The January - September regional temperature across the West North Central region was record warmest in the 1895-2006 record. The South was 2nd warmest. Every other region was either above or much above normal during this period. The Northeast region was 3rd wettest during the year-to-date period.

  • October 2005 - September 2006 was warmer- or much-warmer-than-average for all but one state in the contiguous U.S.  North Dakota experienced record warmth for the period while Oklahoma had its second warmest October to September on record. Six New England states had the wettest such period on record (New York, Maine, New Hampshire, Massachusetts, Connecticut and Rhode Island).

  • Regional temperature ranks for the October to September period were all above to much above average in 2006. The Northeast region was wettest on record during this period. The South was 9th driest.


    See NCDC's Monthly Extremes web-page for weather and climate records for the month of September.

[------- visual page separator -------]
PLEASE NOTE: All of the temperature and precipitation ranks and values are based on preliminary data.  The ranks will change when the final data are processed, but will not be replaced on these pages.  Graphics based on final data are available on the Climate Monitoring Products page.

Citing This Report

NOAA National Climatic Data Center, State of the Climate: National Overview for September 2006, published online October 2006, retrieved on October 23, 2014 from http://www.ncdc.noaa.gov/sotc/national/2006/9.