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Solar activity has been at low levels with mostly weak C-class flares observed from Regions 4172 and 4180.\u00a0 <\/span>The largest flare of the period was a C6.8\/Sf at 15\/1037 UTC from Region 4172.\u00a0 <\/span>There are 12 regions on the disk with most being simple in magnetic complexity.\u00a0 <\/span>Region 4172 remained the largest region on the disk and continued to decay with its magnetic field decreasing in complexity. All remaining regions were quiet and stable. <\/span><\/p>\n No Earth-directed CMEs were observed in available coronagraph imagery. Solar activity is likely to continue at low levels through 17 August.\u00a0 <\/span>Despite their decreasing activity, Region 4172 will help maintain a slight chance (35%) for isolated M-class flares (R1-2\/Minor-Moderate radio blackouts) in the forecast through 15 August.\u00a0 <\/span>Chances decrease to 30% as the region moves beyond the western limb.<\/span><\/p>\n Waning influences from the CH HSS will steadily decrease the flux of 2 MeV electrons, but concentrations at geostationary orbit will remain high most likely through 17 August.\u00a0 <\/span>Last rotation, electrons remained significantly above the 1,000 pfu threshold for seven day with diurnal maximas above threshold for 11 days. <\/span><\/p>\n Solar activity is expected to be at predominately low levels with M-class flare (R1-R2\/Minor-Moderate events) activity likely over 11 August to 06 September. <\/span><\/p>\n No proton events are expected at geosynchronous orbit, barring significant flare activity. <\/span><\/p>\n Geomagnetic field activity is expected to reach active levels on 11 August due to waning positive polarity CH HSS influence.\u00a0 <\/span>Periods of minor storming are likely on 18-20 August, with periods of active conditions likely on 22 August, due to negative polarity CH HSS influence.\u00a0 <\/span>Active conditions are likely again on 28 August in response to anticipated negative polarity CH HSS influence.\u00a0 <\/span>Periods of moderate storming are likely on 05 September, with active levels likely on 04 and 06 September, due to positive polarity CH HSS influence. <\/span><\/p>\n Weekly Commentary on the Sun, the Magnetosphere, and the Earth’s Ionosphere for August 14, 2025 by F. K. Janda, OK1HH: <\/span><\/p>\n The overall level of solar activity did not change significantly in August.\u00a0 <\/span>Medium-size flares were observed almost daily in one or two sunspot groups, while the parameters of the solar wind were most influenced by a coronal hole in the southwestern part of the solar disk.\u00a0 <\/span>This clear situation made it possible to correctly predict the positive phase of the geomagnetic disturbance on August 8 (G1), which manifested itself in improved conditions for ionospheric\u00a0 <\/span>propagation of short waves.\u00a0 <\/span>Particles from the solar flare on August 5 and the intensification of the solar wind from the coronal hole contributed to the disturbance.\u00a0 <\/span>This was followed by a negative phase of the disturbance (G2), during which propagation conditions deteriorated significantly.\u00a0 <\/span>This was followed by only slightly turbulent development. <\/span><\/p>\n The development after August 15 should be calmer, as there are currently no major active areas near the emerging coronal hole in the northeast of the solar disk. <\/span><\/p>\n The Predicted Planetary A Index for August 16 to 22 is 5, 5, 15, 25, 15, 8, and 12, with a mean of 12.1.\u00a0 <\/span>Predicted Planetary K Index is 2, 2, 5, 5, 5, 3, and 4, with a mean of 3.7.\u00a0 <\/span>10.7 centimeter flux is 145, 150, 145, 145, 145, 140, and 145, with a mean of 145. <\/span><\/p>\n For more information concerning shortwave radio propagation, see and the ARRL Technical Information Service web page at, . For an explanation of numbers used in this bulletin, see . Information and tutorials on propagation can be found at, . <\/span><\/p>\n