Weather perfection? Strongest geomagnetic storm in a decade

Does it get any better than this?

Minnesota's reputation as the Land of 10,000 Weather Dramas takes a vacation the next few days. A few spotty showers pop up today around the region. The bulk of rainfall and any severe weather gets shoved south into Iowa and Illinois.

Mixed sunshine, highs near 80 degrees, comfortable humidity. Throw in spectacular northern lights shows and we may have achieved weather nirvana. Cue the band and parades. Summer vacation weather is here. We've earned this.

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Minnesota rides the gap in between weather systems most of this week. Here's a look at the surface features. Most of the green blobs pass north and south.

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NOAA

The severe risk stays mostly south of Minnesota today. Another gnarly thunderstorm outbreak is likely from near Des Moines, Iowa, to Chicago and beyond today and tonight. Yes, my unscientific estimate is that 86 percent of all Minnesotans would classify this as weather perfection.

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AC optional

This is the weather pattern many of us wait for all year long. Highs in the low 80s, lows in the low 60s. If you manage your windows right, letting the cool air in at night and early in the morning air conditioning is optional this week.

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Aurora watch: Strongest geomagnetic storms in a decade

Monday night's aurora dazzled onlookers. I was mesmerized by the best northern lights show I've seen since the 1990s.

Green rays and pulsating waves danced from the northern horizon to directly overhead here at the Weather Lab in Victoria on the relatively dark southwest edge of the metro. The once in a lifetime for many sky show was visible across most of Minnesota Monday night.

This was the view from 6,000 feet up at Mt. Washington in New Hampshire.

The inbound blast of solar energy was the strongest in more than a decade as measured by the U.S. Geological Survey's Geomagnetic Observatory .

Monday night's "planetary K index was of the charts. Last night's values were not sufficient to trigger widespread auroras.

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NOAA

Slate's Eric Holthaus has a good write up on why this week's geomagnetic super-storm is the biggest in at least a decade.

Using the disturbance storm time index, a measure of the severity of geomagnetic storms, Monday night’s event registered at -251 nanoteslas at the USGS geomagnetic observatory in Honolulu, Hawaii—good enough to make it the most intense geomagnetic storm in the current 11-year solar cycle, and putting it just barely into “super storm” territory (the most severe category of geomagnetic storms).

Still, that’s pretty small when compared to some of the biggest solar storms of the past few decades. The strongest geomagnetic storm since modern record keeping began was in March 1989, peaking at about -580 nanoteslas, when a power grid surge produced a blackout for six million people in Canada. The 1859 “Carrington event”—the biggest solar storm since the invention of electricity, estimated at a whopping -1760 nanoteslas—produced aurora worldwide, and channeled so much energy through telegraph wires that operators were able to send messages without batteries. Should an event like that happen today, it’s estimated it would take months or even years to rebuild the global power grid, at a cost of trillions of dollars. That’s why studying space weather is so important—with better predictive models,Earth could hunker down should the big one come barreling our way.

Sunspot AR2371 The culprit for this solar superstorm? Sunspot AR2371. It has a 'beta-gamma-delta' magnetic field that harbors energy for X-class solar flares.

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Sunspot AR2371 has a 'beta-gamma-delta' magnetic field that harbors energy for X-class solar flares. Credit: SDO/HMI

 Aurora watch tonight?

Predicting geomagnetic storms and auroras makes Doppler tornado detection look easy. NOAA predicts an 80% chance for more auroras tonight.

GEOMAGNETIC STORM WARNING: NOAA forecasters estimate a 80% chance of polar geomagnetic storms on June 24th when another CME is expected to hit Earth's magnetic field. The intensity of the storm is hard to predict. It could range from mild to severe.

Here's more on the hazards of severe geomagnetic storms.