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Solar Activity is “High and Intensifying,” NOAA Says

10/25/2013

NOAA’s Space Weather Prediction Center (SWPC) says solar activity is “high and intensifying,” and radio blackouts reaching the R3 levels have been observed over the past 24 hours. An R3 event can cause a wide-area blackout of HF radio communication and a loss of radio contact for about an hour on Earth’s sunlit side. Low-frequency navigation signals may be degraded for about an hour as well.  An X-1 event occurred at 0801 UTC on October 25, followed by an X-2 event at 1503 UTC.

“There is no reason to think this fusillade will end soon, so stay tuned for more flares,” the SWPC said. The Center predicts a 55 percent chance of an R1 (minor) or R2 blackout over the 3 day period, which includes the CQ World Wide DX Contest (phone). The SWPC says there is no indication of a coronal mass ejection (CME) as yet, “but as with the earlier [0801 UTC] event, it would be unlikely to cause geomagnetic storm activity from this launch position at the sun.”

The SWPC says it is still awaiting the impacts of CME activity earlier this week that may bring G1 (minor) geomagnetic storm activity today (a watch is in effect). “More flares are in the offing,” the SWPC advises. “There are now three sunspot groups on the Earth side of the sun capable of strong eruptions.”

As of 1630 UTC, the sunspot number was 148, the A index 1, and the K index 3.



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