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R1 (Minor) Radio Blackout Impacts
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HF Radio: Weak or minor degradation of HF radio communication on sunlit side, occasional loss of radio contact.
Navigation: Low-frequency navigation signals degraded for brief intervals.
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G1 (Minor) Geomagnetic Storms Likely on 31 July and 01 August

Negative Polarity Coronal Hole High Speed Streams
G1 (Minor) Geomagnetic Storms Likely on 31 July and 01 August
published: Monday, August 03, 2015 14:22 UTC

A WATCH for G1 (Minor) geomagnetic storm conditions has been issued for 31 July and 01 August due to the anticipated onset of multiple recurrent negative polarity coronal hole high speed streams (CH HSS).