A long-term winter forecast holds good news for home heating bills but bad news for the Northland's continuing drought and possibly for snow-sports enthusiasts.
The National Climate Prediction Center on Thursday released its updated 90-day outlook for climatological winter -- December, January and February -- and the forecast is for a high probability of higher-than-normal temperatures.
The outlook shows the Northland probably will be above normal, with western Minnesota and the Dakotas even more likely to be warmer.
The outlook says there's an equal chance of above- or below-normal precipitation, which has spurred the prediction that the region's severe drought -- now listed as among the worst in the nation -- will persist or even worsen through at least February.
Duluth and International Falls precipitation totals are almost 7 inches below normal for the year, and some areas of the region are 10 inches below normal. Stream flows and lake levels continue to be well below normal. If the drought lasts into spring, trees stressed during the region's warmest summer on record may succumb to a second season of drought. A lingering drought also could mean a hot spring wildfire season.
ADVERTISEMENT
"Everyone is pointing at us when they're talking about drought nationally. It's not good, and it doesn't look like it's going to get much better,'' said Sam Standfield, climate expert at the National Weather Service in Duluth. "Even a normal snowfall year isn't going to be enough to bring us out of this drought. It's going to take some big spring rains to do it.''
If the developing El Nino hits the moderate level, which is expected, climate analysis shows the Northland should see average winter temperatures about 5 or 6 degrees above normal. There is a strong correlation between moderate and strong El Ninos and warm winters here, Standfield said.
The last moderate El Nino, an unusual warming of Pacific Ocean waters, in 1998-99 brought an average winter temperature of 16.4 in Duluth, 5.7 degrees above average. The last very strong El Nino, in 1997-98, saw average winter temperatures nearly 12 degrees above normal.
"The discussion now is for this El Nino to become at least moderate, and the data shows that's a pretty strong indicator we'll be warmer than normal,'' Standfield said.
Earlier predictions of an El Nino-influenced warmer winter seemed off in October, one of the year's first cold months. But El Ninos historically haven't influenced Northland weather until December or January, weather experts said.
"The strengthening El Nino event will influence the position and strength of the jet stream over the Pacific Ocean, which in turn will affect winter precipitation and temperature patterns across the country," Michael Halpert, lead forecaster at the NOAA Climate Prediction Center, said in a statement on the winter outlook. "This event is likely to result in fewer cold air outbreaks in the country than would be expected to occur in a typical non-El Nino winter."
It's possible but not likely that the Northland's winter will be as warm as last winter, when an unusual flow of Pacific air kept the region cloudy and warm, including the warmest January on record in Duluth.
Eight of 11 months this year have seen above-normal temperatures, including the warmest month in recorded history in Duluth -- July; the warmest January on record; and the warmest summer in recorded history. The only months cooler than normal were February, down 3.1 degrees; October, down 3.7 degrees; and September, down 0.4 degrees. November is shaping up to be warmer than average.
ADVERTISEMENT
Every month since May has seen below-average precipitation. Some areas of northern Minnesota recorded their lowest May-October rainfall totals in recorded history, the Minnesota State Climatology Office reported.
"For parts of Minnesota, they're now saying there's a 60 percent chance of it being above normal and no chance of below normal, and you rarely see that kind of confidence level on it being warmer than average this far north in the winter,'' said Pete Boulay, assistant state climatologist. "For snowfall, the issue will be whether we can keep a snowpack on the ground. It may snow a normal amount, but if it's warmer we may not get the snowpack lasting for snowmobiling or skiing or whatever."
