Are Minnesotans due for a few wet months ahead?
- Article by: BILL McAULIFFE
- Star Tribune
- January 17, 2013 - 9:28 PM
Minnesotans might be in for some drought relief in coming months -- some of it in the form of snow.
Climate models are favoring a cooler- and wetter-than-normal February across the state, according to the nation's long-range outlook issued Thursday by the Climate Prediction Center (CPC).
In the short term, that could mean a revival for snow-removal crews and ski trail groomers. For the three-month period through the end of April, the agency's outlook stays with above-normal precipitation but sees no clear tendencies on temperatures.
"It'd be nice if they were right," said assistant Minnesota state climatologist Pete Boulay.
February is the Twin Cities' driest month on average, with 0.77 inch of precipitation, or 7.8 inches of snow. Even double those amounts would not make much of a dent in the current drought, Boulay noted. Since Aug. 1, official precipitation in the Twin Cities has been 7.75 inches below normal, or less than half the normal amount.
So what would help? A record wet February, and maybe a record wet March, Boulay said. If all of that were snow, it would amount to 26.5 inches in February and 40 more in March.
"But we'll take any moisture we can get," he said.
In suggesting the climate of the northern Great Plains is in for a short-term change, the models apparently relied on a sea-surface temperature phenomenon in the north Pacific Ocean that, like El Niño, is known to affect distant weather, said Anthony Artusa, seasonal forecaster with the CPC. Known as the Pacific Decadal Oscillation, it is expected to create moist southerly flows of air and possibly storm tracks across the central U.S., Artusa said. But it's not expected to alleviate drought in the southern Great Plains, where lack of soil moisture even more severe than Minnesota's will tend to keep the lower atmosphere dry.
Jeff Johnson, chief science officer for the Burnsville-based weather division of global energy management specialist Schneider Electric, said his models aren't calling for the snowy February but do see some possible above-normal precipitation in March and April and into the early part of the growing season. But that trend seems to fall off as summer sets in, he said. That scenario, which over several months averages out to normal, is based on the lack of a strong influence from El Niño or its opposite, La Niña.
"As far as any drought relief, it will be minimal and short-term," he said.
The cold snap expected in the coming days across the Upper Midwest -- the Twin Cities temperature may remain below zero Monday -- may also work against drought relief, Boulay said. With little snow cover, frost will be able to penetrate more deeply into the ground below, extending the time it will be unable to absorb snowmelt.
Although snow cover is below normal across nearly all of Minnesota, the CPC reported Thursday that snow across the northern hemisphere is covering a record area. The hemisphere's land area was cooler than normal in December, particularly across Europe and Asia.
The agency also issued a preliminary finding that within the U.S. in 2012, 485 local annual climate records were set -- 443 for the warmest year on record. Of those, 25 were in Wisconsin, which was second only to Texas' 39. Minnesota had 11, tied for 13th-most on the list. Only one site was the coolest ever. That was in Hawaii.
Bill McAuliffe • 612-673-7646
© 2013 Star Tribune