Updraft: June 1, 2009 Archive

Summer forecast: Cool & dry?

Posted at 9:51 AM on June 1, 2009 by Ken Paulman (2 Comments)

(the following was written by Paul Huttner, who's having technical difficulties today)

Forecasting weather is risky business some days. Sometimes it's tough to get tomorrow right, let alone next weekend. Imagine trying to forecast several months ahead.

That's what the folks at NOAA's Climate Prediction Center (CPC) do. They've shown considerable success over the past few years with seasonal forecasts. They often do best with winter forecasts during El Niño years. The climatic "signals" are strongest during El Niño for regional weather patterns.

Going into last winter, the CPC three-month outlook called for milder than average temperatures in the Upper Midwest. What we got was an old fashioned winter with January temperatures more than 4 degrees below average.

So you'll forgive me if I grab the salt shaker when CPC is forecasting a cool summer for Minnesota. My skepticism is no reflection on the forecast skills at CPC, they are the best. My grain-of-salt approach lies in the fact that the tropical Pacific Ocean is in a state of flux. Tropical Pacific sea surface temperatures (SST's) are on the rise. The cool La Nina pattern of the past year is history. Temperatures have warmed to near average, and nobody knows how warm they will get.

Will El Niño return next winter?

Changes in the Pacific throw climate and weather systems into chaos around the globe, and right here in Minnesota. Seasonal outlook skill is best with certainty in the Pacific. Now CPC is faced with trying to forecast months in advance based on a changing Pacific Ocean. Hurricane forecasters are dealing with the same chaos. How much will changes in the Pacific affect the Atlantic hurricane season that starts today?

One thing is for sure. We're in a drought and it's going to take a significant pattern change to get us out. We're over 10 inches below our precipitation average since last May.

In times like this I'm glad I forecast weather and not climate. I feel a lot better saying we're going to be a bit cool this week, with plenty of sun and a slight chance of showers Tuesday. Even our rain chances this weekend seem far, far away.

PH

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New sunspot cycle may be lowest in 80 years

Posted at 5:00 PM on June 1, 2009 by Ken Paulman (1 Comments)

(This post is Paul Huttner once again - still having computer problems)

NOAA and NASA have issued a new forecast for Solar Cycle 24, which is showing signs of life this week. If the forecast is right, the new sunspot cycle will peak in May 2013 with a peak sunspot number of 90, the lowest since 1928 when Solar Cycle 16 peaked at 78.

The sun was remarkably quiet in 2008. No sunspots were observed 266 of 366 days last year. That's 73% of the time. The sun has been even quieter through March of this year. No sunspot activity was observed on 78 of 90 days, or 87% of the time.

NASA astronomers say our current solar minimum is the deepest in nearly a century.
Douglas Biesecker from NOAA's Space Weather Center says even though the coming solar cycle may be weaker than average, it can still produce strong geomagnetic storms. I interviewed Doug on Jet Streaming earlier this spring.

NASA spacecraft indicate that the sun's brightness has dimmed by 0.02 percent at visible wavelengths and a whopping 6 percent at extreme UV wavelengths since the solar minimum of 1996. The vast majority of climatologists believe these changes are not enough to reverse global warming. Even though we observed reduced solar last year, 2008 was still the 8th warmest year on record globally.

It will be interesting to see how Solar Cycle 24 pans out as we head toward May of 2013. Talk about a long range forecast!

PH

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