SB PROP @ ARL $ARLP052 ARLP052 Propagation de K7RA ZCZC AP52 QST de W1AW Propagation Forecast Bulletin 52 ARLP052 From Tad Cook, K7RA Seattle, WA December 28, 2020 To all radio amateurs SB PROP ARL ARLP052 ARLP052 Propagation de K7RA Merry Christmas. Sunspots went missing last Friday and Saturday, but large new sunspot group 2794 appeared on Sunday, December 21, and on Wednesday Spaceweather.com reported new sunspot group 2795 emerging over our Sun's southeastern limb. This disappearance depressed the average weekly sunspot number, which went from 17.4 last week to 10.3 this week, ending on Wednesday, December 23. Our reporting week runs from Thursday through Wednesday. In spite of lower sunspot numbers, the average daily solar flux increased slightly from 82.1 to 82.8. Average daily planetary A index increased from 4.7 to 7.3, and average daily middle latitude A index went from 3.3 to 6. These are still low numbers, indicating quiet geomagnetic conditions, so 160 meter propagation remains good, also aided by lower seasonal atmospheric noise as winter begins in the Northern Hemisphere. Predicted solar flux for the next 30 days is 88 on December 25 to 30, 86 on December 31, 84 on January 1 to 6, 82 on January 7 to 12, 84 on January 13 to 20, and 86 on January 21 to 23. Predicted geomagnetic indicators for the same period has planetary A index at 15 and 8 on December 25 and 26, 5 on December 27 through January 4, 10 on January 5 and 6, 5 on January 7 to 12, 8 on January 13, 5 on January 14 to 16, then 12, 8 and 18 on January 17 to 19, then 15, 10, 8 and 3 on January 20 and 23. The OK1HH geomagnetic activity forecast for the period December 25, 2020 til January 19, 2021: "Geomagnetic field will be Quiet on: January 4, 12 to 14 Quiet to unsettled on: December 28 to 31, January 1 to 3, 15 Quiet to active on: December 25 to 27, January 6, 8, 10 and 11, 16 Unsettled to active: January 2, 5, 7, 9, 17, 19 Active to disturbed: January 18 Solar wind will intensify on: December (25,) 27 (28 and 29,) (January 1 to 3, 7 and 9, 18,) 19 Remarks: - Parenthesis means lower probability of activity enhancement. - The predictability of changes is lower again, as there are ambiguous and changing indications. I wish you a blessed Christmas, positive thinking and negative tests." Steve, NN4X reported working a VK and a ZL via 15 meter long path around 1915 UTC on December 23 using FT8. NN4X is in Florida, southeast of Orlando. His antenna (two stacked 6 element Yagis) is highly directional, so he has no doubt this was long path. He was also heard at 3D2 and KH6. He writes, "I've been a ham since 1977, and this stuff never gets boring." Check out his impressive array of antennas listed on his QRZ.com page. He sent a pskreporter screenshot showing he was copied all over the world, except Asia. Jeff, N8II wrote on December 19: "Today, we had 2 contests. The RAC and 9A CW (Croatia, everybody works everybody). 15 was a bit marginal into western Canada, but I worked MB, SK, AB, and BC plus several VE3's on backscatter. 15 meters was open to Southern and Central EU at the 1400 UTC 9A CW start, but with few loud signals. By 1500 UTC most activity disappeared. 20 meter signals were loud from both eastern and western Canada and Europe, with the band starting to close around 1615 UTC. My last EU QSOs were with Geoff, GM8OFQ in the Orkney Islands (S9+10db) and Tom G1IZQ (S9 with QSB) just after 1700 UTC. Signals from EU have been weaker and openings much shorter on 15 meters in general this past week due to the drop in solar activity. One day I had a QSO with a loud Norwegian who was S9 around 1400 UTC, but in general most signals have been from southern EU. Our sunsets are already later here by 3 minutes, but sunrises will get later until about December 31 due to the elliptical orbit of the Earth, so openings to the East will get later." Tamitha Skov's latest: https://bit.ly/3aIEWKq For more information concerning radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information Service at http://arrl.org/propagation-of-rf-signals. For an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere. An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive- propagation. More good information and tutorials on propagation are at http://k9la.us/. Instructions for starting or ending email distribution of ARRL bulletins are at http://arrl.org/bulletins . Sunspot numbers for December 17 through 23, 2020 were 12, 0, 0, 11, 11, 11, and 27, with a mean of 10.3. 10.7 cm flux was 81.6, 80.5, 81.7, 83.8, 79.6, 85.8, and 86.4, with a mean of 82.8. Estimated planetary A indices were 2, 3, 5, 4, 12, 13, and 12, with a mean of 7.3. Middle latitude A index was 2, 2, 4, 4, 8, 11, and 11, with a mean of 6. NNNN /EX