(Thanks to Dennis Bryant and his excellent blog for bringing this to our attention)

USCG NAVIGATION CENTER

HIGH HORIZONTAL DILUTION OF PRECISION (HDOP) ADVISORY FOR 29 JULY 2016

Users of the Global Positioning System (GPS) in an area extending to the Northeast from Fort Collinson and Ulukhaktok to the Northeaster tip of Victoria Island in The Beaufort Sea, and in an area of the Antarctic Coast to the Southeast of the South Georgia and South Sandwich Islands may experience short periods of high HDOP/PDOP (HDOP >6) at various times between 291123Z and 291131Z July 2016 due to satellite maintenance (please refer to NANU 2016047, available on our Constellation Status Page).

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