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NOAA Issues Moderate (G2) Geomagnetic Storm Watch for September 11

09/11/2018

Just as Hurricane Florence approaches the US mainland and Hurricane Olivia is poised to affect Hawaii, NOAA has issued a G2 (moderate) geomagnetic storm watch for September 11. The G2 storm could exacerbate already modest propagation on HF bands as the planetary K index rises to an estimated value of 6. The G2 forecast stems from a fast-moving stream of coronal hole solar wind that’s expected to hit Earth’s magnetic field. During G2 storms, auroras can appear along the northern tier of the US. Among other effects, a G2 storm could cause HF fading at higher latitudes. 



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