While we’re concentrating on the collapse of arctic sea ice, the drought goes on.

Michael Lemonick in Climate Central:

The massive and widespread 2012 drought that has gripped the nation since the spring refuses to die, according to the latest report from the U.S. Drought Monitor — and in fact, it’s expanded a little: as of September 18, 64.82 percent of the contiguous U.S. was suffering from at least moderate drought, slightly more than the 64.16 percent reported a week earlier, enough of a gain to set a new record for this drought category.

At the same time, NOAA released its seasonal drought outlook for the period ending December 31, and it offers little prospect for significant improvement. Drought is projected to persist in a huge swath of the country, especially in the West from Southern California to West Texas, north to Wisconsin, and back west to Montana, Idaho, southeastern Oregon and back down to Nevada — and everywhere in between.

In addition, drought conditions are projected to develop during the period in the rest of the Pacific Northwest and Upper Midwest. A small swath from south Texas up through Indiana and parts of Ohio may see “some improvement” in drought conditions, as might parts of Alabama, Georgia and South Carolina. The rest of the East and Southeast are mostly unaffected by drought at this time, and that is projected to continue.

The drought forecast for the next few months is being shaped by the expected influence of a developing El Niño event in the equatorial tropical Pacific Ocean. Such events are characterized by warmer than average sea surface temperatures, which can profoundly reshape weather patterns in the U.S. and elsewhere. El Niño winters tend to be wetter than average in the South and the Ohio Valley.

In a conference call with reporters on Thursday, Hugh van den Dool, a climate forecaster with NOAA’s Climate Prediction Center, said El Niño conditions are not developing quickly, and is likely to be modest in strength.

“We believe there will be an El Niño,” van den Dool said, “but the strength of it is debatable, and it may be a fairly weak one.” He said water temperatures halted their increase during September, and this may prevent a strong El Niño event from occurring. “We expect this will intensify a little bit as we get into later fall, but it is probably too late to get a major El Niño.”

The Climate Prediction Center’s forecasts show above average temperatures are likely across the northern tier of the country through December. As is typical during El Niño winters, the southern tier of the country is forecast to have above average precipitation through December, particularly the Gulf Coast region from Texas to Florida.

As for what’s going on currently, if you include slightly less severe “abnormally dry,” category, the percentage of the Lower 48 rated as drier than normal leaps to a whopping 78.15 percent, although that represents an (infinitesimal) retreat from the previous week’s 78.53 percent.

For the most severe category, “exceptional drought,” the new number is 5.96 percent of the lower 48, down from 6.26 percent the previous week, and if you add the second most severe, “extreme drought,” the total for both categories are now 20.74 percent, down from the previous week’s 21.09.