Web posted Thursday, June 25, 1998
at 4:31 PM ET

By Environmental News Network staff

La Niņa may bring a wet and cold early winter to the Northwest, a forecast ski resorts like Idaho's Sun Valley like to hear.

Watch out. Here comes El Niño's angry little sister -- La Niña.

National Oceanic and Atmospheric Administration forecasters said this week that La Niņa conditions are developing in the tropical Pacific Ocean and will likely influence fall and winter weather patterns.

La Niña means "the little girl" and is sometimes called El Viejo (old man).

La Niņa features colder than normal sea surface temperatures in the tropical Pacific Ocean. La Niņa often implies drier than normal conditions in the Southwest in late summer, the Southwest and central Plains in the fall and the Southwest and Southeast in the winter.

In contrast, the Pacific Northwest is likely to be wetter than normal in the late fall and early winter with the presence of a well-established La Niņa.

Temperature wise, La Niņa winters are usually warmer than normal in the Southeast and colder than normal in the Northwest.

"There was a rapid cooling of sea surface temperatures in sections of the equatorial Pacific during May as El Niņo conditions rapidly dissipated," said Vern Kousky, research meteorologist with NOAA's Climate Prediction Center in Camp Springs, Md. "The cooling trend is likely to continue with the development of La Niņa conditions during the next three to six months. We expect that La Niņa will be impacting weather patterns around the globe this fall and into next winter."

"These forecasts are a prime example of the payoff for investments in research and development," said D. James Baker, NOAA administrator. "Thanks to administration and congressional support, we have the systems in place to monitor the early signs of these major events."

La Niņa features colder than normal sea surface temperatures in the tropical Pacific Ocean.

The long-term climate outlook issued by NOAA this week calls for warm and dry conditions in the Southwest during July, August and September, and continuing through the fall and winter. This is of particular concern because the area encompassing Arizona, New Mexico and much of Texas is already quite dry.

The Gulf Coast states to east of Texas, also currently quite dry, are forecast to have normal chances of precipitation in the summer months.

According NOAA , cool conditions will prevail during the next three months in the northern Great Plains. Dry conditions are expected for interior Washington and Oregon during that time. The dryness forecast for the Southwest is expected to also extend into the central Great Plains in the fall and later into the Southeast in the late fall and winter.

"La Niņa will certainly bring us a different winter next year than we observed in 1998," added Kousky. "There will be a tendency for more variability in our daily and monthly weather patterns because the jet stream is expected to be situated over the central United Sates rather than over northern Mexico and the northern Gulf of Mexico as observed during last winter."

Nationally, the spring of 1998 (March - May) was the 47th wettest and the 24th warmest spring on record since detailed records began in 1895, according to the preliminary data from NOAA's National Climatic Data Center in Asheville, N.C.

The wettest spring on record, according to NOAA, occurred in 1973 with a national average precipitation of 10.14 inches. The driest spring on record, with a national average precipitation of 5.32 inches, occurred in 1925.

"Despite the near-normal national precipitation value for the spring season, areas of extremes did exist," said William Brown, meteorologist at the NCDC. "For example, spring 1998 was the seventh driest on record for the South region and the eighth wettest since 1895 for the West region. Spring 1998 was the third driest on record for Texas and the fifth driest such season for Louisiana."

To the opposite extreme, spring 1998 was the second wettest spring for Idaho, sixth wettest for Nevada and Virginia, seventh wettest for Rhode Island, eighth wettest for California, and tenth wettest for Connecticut and New Jersey.

The 1961-1990 normal spring temperature was 51.6 degrees F. The 1998 national averaged spring temperature was 52.4 degrees F. The warmest spring on record, with a national average temperature of 54.7 degrees F, occurred in 1910. The coolest spring on record occurred in 1917 with a national average temperature of 48.1 degrees F.

Regionally, spring 1998 was the fifth warmest spring since 1895 for the Northeast region and the sixth warmest for the East-North Central region. It was the 20th coolest spring on record for the West region. Spring 1998 was the warmest on record for New Hampshire, second warmest for Rhode Island, third warmest for Connecticut and New York, fourth warmest for Vermont and Wisconsin, fifth warmest for Michigan and Minnesota, sixth warmest for Delaware, New Jersey, and Ohio, seventh warmest for Maine and Massachusetts, eighth warmest for Pennsylvania, and 10th warmest for Maryland. It was the 14th coolest spring since 1895 for California and the 24th coolest such season on record for Arizona.

"As with the recent record El Niņo, the Department of Commerce will work closely with our federal agency partners such as FEMA and state and local emergency managers to make sure that the latest weather information is available to prepare communities early and mitigate potential economic and safety impacts," said Commerce Secretary William M. Daley.

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