{"id":798963,"date":"2025-10-31T13:42:39","date_gmt":"2025-10-31T18:42:39","guid":{"rendered":"https:\/\/spaceweekly.com\/?p=798963"},"modified":"2025-10-31T13:42:39","modified_gmt":"2025-10-31T18:42:39","slug":"the-arrl-solar-update-6","status":"publish","type":"post","link":"https:\/\/spaceweekly.com\/?p=798963","title":{"rendered":"The ARRL Solar Update"},"content":{"rendered":"<p> <br \/>\n<\/p>\n<div>\n\t\t\t\t\t<span class=\"date\">10\/31\/2025<\/span><\/p>\n<p>Solar activity has decreased to very low levels. Region 4266<br \/>exhibited signs of slight development as it gained asymmetric<br \/>penumbra surrounding its trailing spots. Meanwhile, Region 4267<br \/>underwent decay, losing several leading spots. Additional activity<br \/>included a coronal mass ejection (CME) off the NE limb on October<br \/>29.<br \/>\u00a0<br \/>An associated Type II radio sweep was reported with the CME; however<br \/>SUVI 195 imagery revealed the CME to have originated on the far<br \/>side. Also, an approximate 12 degree filament eruption, centered<br \/>near N27W24 was observed becoming unstable beginning October 29.<br \/>Most of the material of this event appeared to have been reabsorbed<br \/>with perhaps a faint and narrow CME escaping. Modeling of this event<br \/>revealed a possible glancing blow to the north of Earth by late on<br \/>November 2, but confidence is low in both the analysis of this event<br \/>and the modeling outcome.<br \/>\u00a0<br \/>Solar wind parameters continued to reflect positive polarity coronal<br \/>hole high speed stream (CH HSS) influences. Solar wind parameters<br \/>are expected to continue to reflect positive CH HSS influences<br \/>through November 1.<\/p>\n<p>Weekly Commentary on the Sun, the Magnetosphere, and the Earth&#8217;s<br \/>Ionosphere, October 30, 2025, by F. K. Janda, OK1HH:<\/p>\n<p>&#8220;It is very rare for the situation on the Sun and between it and<br \/>Earth to be as relatively simple and clear as it has been in recent<br \/>days. This is one of the reasons why it was possible to make a<br \/>fairly accurate prediction of further developments. Although there<br \/>were concerns that an intensified solar wind could hit Earth as<br \/>early as October 26, the original forecast ultimately proved<br \/>accurate and the disturbance began on October 28. The last weekend<br \/>in October was thus marked by relatively good conditions for radio<br \/>wave propagation on all shortwave bands.<\/p>\n<p>&#8220;Regular helioseismological observations of the far side of the Sun<br \/>are closely monitoring the only two currently active regions on the<br \/>Sun. They will begin to emerge on the eastern edge of the solar disk<br \/>in the first half of next week, which will immediately be reflected<br \/>in an increase in solar flux. This may peak around October 10, but<br \/>it seems that it will happen sooner.<\/p>\n<p>&#8220;The increase in solar activity during the usual favorable seasonal<br \/>changes alone will result in improved conditions for shortwave<br \/>propagation. With a little luck, the improvement could peak around<br \/>November 8, when the next increase in geomagnetic activity can be<br \/>expected.&#8221;<\/p>\n<p>Solar activity is expected to be at moderate levels until November<br \/>15 due to the return of Region 4246. Low levels are expected to<br \/>prevail from November 14 to 22 as multiple regions depart the<br \/>visible disk.<\/p>\n<p>A greater than 2 MeV electron flux at geosynchronous orbit is<br \/>expected to be at high levels until November 15 due to responses<br \/>from recurrent CH HSS influences.\u00a0 Moderate levels are expected from<br \/>November 16 to 22.<\/p>\n<p>Geomagnetic field activity is expected to be at quiet to unsettled<br \/>levels on November 1 to 6, 10 to 14, and November 16 to 22.\u00a0 Active<br \/>conditions are expected from November 7 to 9, and November 15.<\/p>\n<p>The latest video report from Dr. Tamitha Skov, WX6SWW, can be found<br \/>on YouTube at,  .<\/p>\n<p>Spaceweather.com for October 31 reports on &#8220;Halloween Fireballs&#8221; and<br \/>the rapid brightening of Comet 3I\/ATLAS.<\/p>\n<p>The Predicted Planetary A Index for November 1 to 7 is 8, 5, 5, 5,<br \/>5, 5, 8, and 12, with a mean of 6.9.\u00a0 Predicted Planetary K Index is<br \/>3, 2, 2, 2, 2, 3, and 4, with a mean of 2.6.\u00a0 10.7-centimeter flux<br \/>is 130, 130, 135, 140, 140, 140, and 140, with a mean of 136.4.<\/p>\n<p>For more information concerning shortwave radio propagation, see<br \/> and the ARRL Technical Information<br \/>Service web page at,  For<br \/>an explanation of numbers used in this bulletin, see<br \/> . Information and<br \/>tutorials on propagation can be found at,  .<\/p>\n<p>Also, check this:<\/p>\n<p>https:\/\/bit.ly\/3Rc8Njt<\/p>\n<p>&#8220;<em>Understanding Solar Indices<\/em>&#8221; from September 2002 <em>QST<\/em>.<\/p>\n<p>\u00a0<\/p>\n<\/p><\/div>\n<p><br \/>\n<br \/><a href=\"http:\/\/www.arrl.org\/news\/view\/the-arrl-solar-update-7?rand=771671\">Source link <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>10\/31\/2025 Solar activity has decreased to very low levels. Region 4266exhibited signs of slight development as it gained asymmetricpenumbra surrounding its trailing spots. Meanwhile, Region 4267underwent decay, losing several leading&hellip; <\/p>\n","protected":false},"author":1,"featured_media":771673,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-798963","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-ARRL"],"_links":{"self":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/posts\/798963","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=798963"}],"version-history":[{"count":0,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/posts\/798963\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/media\/771673"}],"wp:attachment":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=798963"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=798963"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=798963"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}