WINTER UNUSUALLY COLD IN THE EAST, WARM IN THE WEST
March 20, 2003 — Winter 2002-03 was a season of stark contrasts in the United States, with colder-than-normal temperatures and periods of heavy snowfall prevailing in the East, while unusual warmth and persistent drought covered most of the West. For the globe, the average surface temperature was the 6th warmest on record during the December-February period, according to NOAA. (Click NOAA image for larger view of NOAA statewide winter temperature rankings for 2002-2003. Click here for high resolution version, which is a very large file. Please credit “NOAA.”)
Scientists from the NOAA National Climatic Data Center in Asheville, N.C., today said, based on preliminary data, the average temperature for the contiguous United States during meteorological winter (December-February) was 34.0 degrees F (1.1 degrees C), which was 1.0 degree F above the 1895-2002 mean, but well below the record warm winter of 1999-2000, when the average temperature was 37.0 degrees F (2.8 degrees C). Four of the previous five winters were much warmer than average.
Twenty seven states in the eastern half of the United States experienced significantly colder-than-average weather. The below-average temperatures in the East contrasted sharply with the winter of 2001-2002, particularly in the Northeast, which had its warmest winter season on record last year. The average temperature was 10.0 degrees F lower this winter in that region. Although temperatures were much lower than in most winters of the past couple of decades, few record cold temperatures were established and no state had a much-below-average temperature (lowest 10 percent) for the season.
record warm temperatures were prevalent in the western United States in
mid-winter, and two states (Nevada and Utah) had their warmest January
Drought persisted in many of the same areas in the West that have experienced drought for the past three to five years. At the end of the winter season, 68 percent of the West was in moderate-to-extreme drought, based on the Palmer Drought Index.* Much-wetter-than-average conditions will be needed to end long-term drought by summer’s end in many areas. (The most widespread drought on record occurred in July 1934, when 97 percent of the West was in moderate to extreme drought.) After an extremely dry January from Colorado and New Mexico to California, precipitation amounts were generally higher in February, most notably in the Southwest. However, snow pack levels at the end of the season were less than 70 percent of average in much of the West, and statewide reservoir storage was below average in every western state. (Click NOAA image for larger view of NOAA statewide winter precipitation rankings for 2002-2003. Click here for high resolution version, which is a very large file. Please credit “NOAA.”)
Abnormally dry conditions spread east into the Upper Midwest, where the winter season was the second driest on record in Wisconsin, Iowa and Minnesota. Michigan had its driest winter since statewide records began in 1895, and by the end of February, severe drought covered much of the state.
Precipitation for the season was also significantly less than average from Kansas to North Dakota and in Illinois, Ohio, Vermont, New Hampshire and Maine. Areas to the east and south experienced significantly wetter- and snowier-than-average conditions. Record or near record snow fell from northern Virginia to Boston in mid-February. Heavy snow fell in the North and South Carolina in January, and severe ice storms affected those states in December and February.
The combined land and ocean surface temperature for December-February was the sixth warmest on record, while the average temperature in the lower troposphere (the lowest 5 miles of the atmosphere) tied December-February 2001-2002 as the second warmest on record . Since 1900, global surface temperatures have risen at a rate of 1.0 degree F/century (0.6 degrees C/century), but the rate has increased to approximately three times the century-scale trend since 1976.
El Niño conditions prevailed during the period but were significantly weaker by the end of February, according to the NOAA Climate Prediction Center. Sea-surface temperature anomalies had decreased by more than 3.5 degrees F (2 degrees C) in the eastern equatorial Pacific and continued weakening is expected.
The NOAA National Environmental Satellite, Data, and Information Service (NOAA Satellite and Information Services) is the nation’s primary source of space-based and surface-based meteorological and climate data. NOAA Satellite and Information Services operates the nation's environmental satellites, which are used for weather forecasting, climate monitoring and other environmental applications such as fire detection, ozone monitoring and sea surface temperature measurements.
NOAA Satellite and Information Services also operates three data centers, which house global databases in climatology, oceanography, solid earth geophysics, marine geology and geophysics, solar-terrestrial physics and paleoclimatology.
NOAA is dedicated to enhancing economic security and national safety through the prediction and research of weather and climate-related events and providing environmental stewardship of the nation’s coastal and marine resources. NOAA is part of the U. S. Department of Commerce.
* The Palmer Drought Index uses numerical values derived from weather and climate data to classify moisture conditions throughout the contiguous United States and includes drought categories on a scale from mild to moderate, severe and extreme.