SIZZLING SUMMER WEATHER
July 21, 2005 — From coast to coast, people are looking for ways to escape the sizzle of summer weather. Over the past week, many cities across the country have set or broken records for daily highs or for high minimum temperatures. Also, the heat index values have been particularly high over the East the past few days due to very high humidity levels, which also has resulted in warm nighttime temperatures. (Click NOAA image for larger view of heat and drought collage. Please credit “NOAA.”)
The latest wave of heat sweeping across the nation has many people wondering: is this unusual? Forecasters say, a strong ridge of high pressure at the upper levels, centered in southeastern Utah, has turned up the heat in the region recently (since about July 10). This ridge center is somewhat stronger than normal and is displaced slightly from its typical climatological position in west-central New Mexico.
"Typically, the warmest temperatures of the year in the southwestern United States occur in June or early July, just before the start of the monsoon season," said Wayne Higgins, principal climate scientist at the NOAA Climate Prediction Center. "Over the past several days high pressure aloft over the four corners of the region has become established and will bring monsoon moisture into Arizona and New Mexico," Higgins added. During the next week the chances for showers and thunderstorms will increase as remnant moisture from former tropical system Emily moves across northern Mexico and into southern Arizona from east to west. This will help to lower daytime maximum temperatures from their recent record values.
Also, the monsoon season in the Southwest United States typically begins in early July, but this year we have had a late start. Because the monsoon season is short, typically spanning July-September, it is hard to make up for lost time. Thus, it is most likely that the monsoon will be lackluster overall, consistent with NOAA's August-October seasonal outlook, which calls for below normal precipitation in the region.
The NOAA Climate Prediction Center's Seasonal Outlook released today calls for the August through October temperatures to be above normal along the West coast, in the Southwest, the west-central Plains, and western and southern Texas. South Florida and much of the deep South are also expected to have above normal temperatures during the period. Rainfall is expected to be above normal along the south Atlantic coast from Virginia through Florida; while below normal rainfall is expected throughout the Great Basin and the Southwest.
In conjunction with the Seasonal Outlook, today NOAA released its U.S. Seasonal Drought Outlook which reports the soaking rains from Hurricane Emily are expected to result in drought improvement across the southern most counties of Texas. However drought is expected to remain a concern over areas of the Pacific Northwest and the Southwest.
NOAA cautions the public that heat waves can be deadly. During the summer months, it is important for everyone to stay abreast of the weather and know preventive measures to take in order to keep safe. During heat waves, those especially susceptible to heat danger are the homeless, elderly and pets. NOAA has a Web site dedicated to weather safety with tips on how to be prepared in extreme weather events.
NOAA, an agency of the U.S. Department of Commerce, 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.
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