June Wetter and Cooler Than Average in Much of Nation;
The eastern two-thirds of the nation was cooler than average and much of the eastern and southern United States was wetter than average in June, according to scientists at the NOAA Climatic Data Center in Asheville, N.C. Overall, the contiguous United States had its sixth coolest and seventh wettest June since national records began in 1895. The global average temperature was third warmest on record.
NOAA scientists report that the average temperature for the contiguous United States in June (based on preliminary data) was 66.8 degrees F (19.3 degrees C), which was 2.5 degrees F (1.4 degrees C) below the 1895-2003 mean. Four states (Kentucky, Indiana, West Virginia and Pennsylvania) had their coolest June and five states (Oklahoma, Arkansas, Tennessee, Mississippi and Florida) their second coolest June since records began in 1895. Conversely, significantly warmer-than-average temperatures occurred in Arizona, Nevada, Oregon and Washington. The average June temperature in Alaska was 2.6 degrees F (1.5 degrees C) above the 1961-1990 mean, the second warmest June on record for the state.
The unusual warmth in the West and the cooler-than-average temperatures elsewhere were largely due to a dominant high pressure area over the western United States and a June jet stream pattern that persistently pushed unusually far south through southern and eastern regions of the nation. This pattern also contributed to record and near-record monthly rainfall totals in parts of the East and extremely dry conditions in the Pacific Northwest. Twenty-four states were significantly wetter than average with the most anomalously wet states in the Deep South and mid-Atlantic from New Jersey to Virginia.
Central Park in New York City had its wettest June since records began more than a century ago. The wet June was part of an extended period of above average rainfall in which measurable precipitation fell on 10 of 13 weekends from April through June at the park. April-June was the wettest such three-month period on record in the Southeast region. Alabama and Virginia set statewide precipitation records for the same period, and Georgia and the Carolinas had their second wettest April-June since statewide records began in 1895. Tropical Storm Bill came ashore along the Louisiana coast on the last day of June and brought heavy rainfall to areas along its path as its remnants moved into Mississippi and Alabama and slowly into other parts of the Southeast during the first few days of July.
The widespread wet conditions in the East were a sharp contrast to continued warmer and generally drier-than-average conditions in large parts of the West. Oregon had its driest June on record and Washington state its fifth driest. Three other western states (Nevada, Idaho and Montana) were significantly drier than average. The lack of rainfall combined with unusually warm temperatures led to persistent or worsening drought in many areas. But conditions continued to improve in parts of Colorado as rainfall totals for the month were generally higher than average.
Drought has affected many areas of the West for the past three to five years. Although there has been some improvement since last year, at the end of June 2003, 51 percent of the West was in moderate-to-extreme drought, based on a widely used measure of drought, the Palmer Drought Index. At its most recent peak in August 2002, moderate to extreme drought affected 87 percent of the West. The long-term drought is expected to contribute to an above normal fire season in the interior West, Northwest and portions of California and the Northern Rockies, according to the National Interagency Fire Center. The dry conditions also continued to adversely affect farming and ranching activities in many western states, according to the U.S. Department of Agriculture.