Propagation Update – January 5, 2018

QST de W1AW Propagation Forecast Bulletin 1  ARLP001 From Tad Cook, K7RA Seattle, WA  January 5, 2018 To all radio amateurs No sunspots appeared from December 27, 2017 until January 4, 2018. As Solar Cycle 24 declines to a minimum over the next two years we should see longer and more numerous periods of no sunspots. On January 4 the daily sunspot number was 13, indicating 3 sunspots in one sunspot group, although Spaceweather.com reported no sunspots on that day. The sunspot number for that day was reported by NOAA…

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Propagation de K7RA

ZCZC AP51 QST de W1AW Propagation Forecast Bulletin 51  ARLP051 From Tad Cook, K7RA Seattle, WA  December 16, 2016 To all radio amateurs   Average daily solar indices over the past week were lower than the previous seven days, with average daily sunspot number declining from 40.9 to 13, and average daily solar flux dropping 10 points from 82.2 to 72.2. Geomagnetic indicators were higher, with average daily planetary A index rising from 4.9 to 13.3, and mid-latitude A index from 3.4 to 9. Predicted solar flux is 72 on…

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Propagation de K7RA – December 2, 2016

QST de W1AW Propagation Forecast Bulletin 49 ARLP049 From Tad Cook, K7RA Seattle, WA December 2, 2016 To all radio amateurs   SWS Geomagnetic Disturbance Warning 16/53 issued at 2301 UTC/01 December 2016 by the Australian Space Forecast Centre. A small coronal hole will move into a geoeffective position around 4 Dec. This could result in brief active to minor storm periods from late 3 Dec or early 4 Dec. Increased geomagnetic activity expected due to coronal hole high speed wind stream from 03 to 04 December 2016 GEOMAGNETIC ACTIVITY…

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Solar Update de K7RA

Source: ARRL News 05/20/2016 Average daily solar flux and sunspot numbers rose over the past week. The average daily sunspot number rose 5 points to 64.1 while average daily solar flux was up 11.6 points to 100.4. Geomagnetic indices were quieter, with average planetary A index decreasing from 22.6 to 9.9 and average mid-latitude A index dropping from 14.6 to 10.9. USAF and NOAA predict solar flux at 100 on May 20-24, 95 on May 25-26, 90 on May 27-28, 95 on May 29, 100 on May 30 through June 1,…

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Solar Update de K7RA

Source: ARRL News 05/13/2016 There was a whopper of a geomagnetic storm on Mother’s Day, May 8, when the planetary A index reached 70. In Alaska, the college A index was 117. Aurora was visible in North America well south of the northern tier states. Average daily sunspot number dropped 15.6 points to 59.1 over the past week, and average daily solar flux declined 3.1 points to 88.8. Average daily planetary A index over the same period doubled from 11.3 to 22.6, and average daily mid-latitude A index rose 3.9…

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Solar Update de K7RA

Source: ARRL News 05/06/2016 Solar activity increased last week, making one of those occasional upticks on the way down from the peak of the solar cycle. Average daily sunspot numbers increased from 43.3 to 74.7, and average daily solar flux increased by ten points to 91.9. Average planetary A index went from 9.4 to 11.3 and average mid-latitude A index went from 11.6 to 10.7. At 0415 UTC on May 2 the Australian Space Forecast Centre issued a geomagnetic disturbance warning. At the end of the day, the planetary A…

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Solar Update de K7RA

Source: ARRL News 04/29/2016 At 0121 UTC on April 29 the Australian Space Forecast Centre released a geomagnetic disturbance warning for April 30 and May 1. Increased geomagnetic activity is predicted due to high speed solar wind coming from a coronal hole. There is a chance of minor storm levels. Over the past reporting week (April 21-27), average daily sunspot numbers rose from 40 to 43.3, and average daily solar flux declined from 100.8 to 81.9. This is compared to the previous seven days. Average planetary A index went from…

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Solar Update de K7RA

04/22/2016 Over the past reporting week, April 14-20, average daily sunspot numbers rose from 32 to 40, while average daily solar flux declined from 106.1 to 100.8. Average daily planetary A index declined from 12.4 to 10.9, but average daily mid-latitude A index rose slightly from 8.3 to 8.9. The mid-latitude A index uses 3-hour data from a magnetometer at Fredericksburg, Virginia, and the planetary numbers are derived from readings at Sitka, Alaska; Meanook, AB, Canada; Ottawa ON, Canada; Fredericksburg, Virginia; Hartland, UK; Wingst, Germany; Niemegk, Germany; and Canberra, Australia.…

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Solar Update de K7RA

04/08/2016 All solar and geomagnetic indicators declined again last week. Compared to the previous seven days, from March 31 through April 6 the average daily sunspot number slipped from 28.1 to 19.4. Average daily solar flux sank from 88.8 to 83.1, while average daily planetary A index went from 11.9 to 9.4. Average daily mid-latitude A index went to 7.6 from 8.6. The latest prediction (from April 7) has solar flux at 92 and 90 on April 8-9, 95 on April 10-15, 78 on April 16-17, 80 on April 18-22,…

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Solar Update de K7RA

Source: The ARRL News   03/25/2016 All of the indicators we track were lower over the past week (March 17-23), compared to the previous 7 days. Average daily sunspot numbers declined from 51.7 to 28.4, and average daily solar flux was 88.8, compared to 98.6 during the prior 7 days. Planetary A index was lower by 3.8 points to 11.9, and average mid-latitude A index (measured in Wallops Island, Virginia) was down from 12 to 8.6. Lower geomagnetic indices are generally considered a good thing for HF propagation. Looking at…

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