We're in a strong solar cycle

Sunspots are storms on the sun and during the height of a cycle, its magnetic poles will usually flip as the North Pole becomes the South Pole and vice-versa. The last solar cycle, which was number 24, began in late 2008 and ended in late 2019. That one was the weakest in recorded history and we’re now in Solar Cycle 25, a much more active one, which is the 25th cycle since 1755 when extensive observations of the Sun began.

Within the last year, the number of sunspots has been the highest since 2002. For much of 2023, the average number of sunspots reported per day on the Sun has been close to 140. Over the last month, the average has been 145 sunspots observed per day. Historically, the average number of sunspots is about 175 during each cycle when the Sun is in its “maxima” phase. During the “minima” in the 2010s, the average number of sunspots was 81, but there were long stretches with no sunspots reported.

There were several days in September when sunspots topped 200. The highest was 220 on Sept. 22, while the next day reported 211. Many scientists are speculating that we may be experiencing one of the strongest cycles in recorded history, which likely means more solar storms.

With the high number of sunspots, there is a concern for solar flares that would have the potential to damage electronic equipment or satellites orbiting the Earth. The most powerful solar flares are X-class storms. According to space.com, a strong solar storm swept across the Earth, forcing a 4.5-hour delay to a Starlink launch from Florida on Feb. 27. The solar storm also disrupted GPS signals resulting in the pausing of operations of several Canadian oil rigs.

Last year, the sun produced seven X-class flares. For the first nine months of this year, there have been 20. During the first eight days of August, there were two strong X-class flares. On Aug. 7, according to space.com, a powerful solar flare disrupted radio and navigation signals across North America. Forecasters who observe the sun and space issued warnings due to the high energy particles slamming into the Earth. That particular flare was classified as an X1.5, which was the most potent solar flare category for this “maxima” solar cycle.

In addition to sunspots, the chances of CMEs are higher during this “maxima” cycle. A coronal mass ejection (CME) is a large release of plasma and accompanying magnetic field from the sun’s corona, which is the outer layer of its atmosphere. They will often follow solar flares and be released into the solar wind. They will travel away from the sun and can reach our planet as fast as 15-18 hours.

The magnetic field around our planet protects us from the harmful effects of the sun. Scientists say that it’s generated by the Earth’s liquid iron core. The core’s continuous cooling and crystallization lead to powerful electrical currents that generate our magnetic field into space. When charged particles from the Sun interact with our magnetic field, they will give off light. During a strong event, people in the northern latitudes will be treated to a magnificent light show called the aurora borealis, or the northern lights.

The northern lights are often visible to those in far northern Canada, Europe, Alaska and other areas of very high latitudes. However, if the Earth receives a strong CME, the lights can be visible much farther to the south. During the infamous Carrington Event in 1859, when a super-strong solar flare hit the Earth, auroras were seen in areas as far south as Cuba and Hawaii. In mid-July, auroral activity was spotted in Idaho from a solar flare event. During the late hours of Sept. 18 into the early morning of Sept. 19, residents from northern Idaho southward to Idaho were also provided a dazzling display of the northern lights.

The latest solar cycle is not expected to peak until at least 2024 or 2025. Therefore, solar activity is expected to remain high with additional chances of our planet being impacted by solar flares or CMEs. There are many astronomical websites, including space.com, that will provide the probabilities of more northern light shows several days in advance.

In terms of our local weather, the full moon cycle weather change started a little early, but we did manage to receive 0.69 inches of rain in Coeur d’Alene from Sept. 26 through 29. Other locations were close to an inch or more of precipitation. North Idaho College received 0.91 inches of rain while Hayden had around 1.25 inches. Despite the much-needed rainfall, our September precipitation total ended up below the average of 1.48 inches in Coeur d’Alene.

Conditions this week are expected to be mostly dry across the Inland Northwest. However, rainfall is expected to increase across the region around the early portion of next week. The normal rainfall for October in Coeur d’Alene is 2.22 inches. We believe there’s a good chance of getting close to that figure this month as the jet stream is expected to occasionally move over our region.

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Contact Randy Mann at randy@longrangeweather.com.