Daily Report

(last updated 29 Aug 2025 23:30 UT)

SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT ISSUED AT 2330UT/29 AUGUST 2025 FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE SUMMARY FOR 29 AUGUST AND FORECAST FOR 30 AUGUST - 01 SEPTEMBER STATUS INDICATORS SOL:** YELLOW ** MAG:GREEN ION: GREEN ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx ----------------------------------------------------------- 1A. SOLAR SUMMARY Activity 29 Aug: R0 Flares Max Fadeout Freq. Sectors M1.0 0416UT possible lower E. Asia/Aust. Observed 10.7 cm flux/Equivalent Sunspot Number for 29 Aug: 222/172 1B. SOLAR FORECAST 30 Aug 31 Aug 01 Sep Activity R1-R2 R1-R2 R1-R2 Fadeouts Possible Possible Possible 10.7cm/SSN 225/175 230/180 220/170 COMMENT: Solar activity on UT day 29-Aug was R0, with no solar flares. There are currently six numbered sunspot regions on the solar disk. AR4197 (S17E05, beta-gamma) remains the most complex region on the disk and has grown over the past day. This region has potential to develop delta spots to increase its complexity. All other sunspot regions are either stable or in decay. Solar activity is expected to be R1-R2 over 30-Aug to 1-Sep. A CME was observed from 29/1700 UT off the southwestern solar limb, however this has been analysed as a farside event and therefore not Earth-directed. No other CMEs were observed. The >10 MeV protons remain slightly enhanced, although on a downward trend. S0 solar radiation storm conditions were observed on UT day 29-Aug. S0 solar radiation storm conditions are expected over 30-Aug to 1-Sep. The solar wind environment on UT day 29-Aug was stable and near background levels. The solar wind speed ranged from 358 to 445 km/s and is on a steady trend. The peak total interplanetary field strength (IMF, Bt) was 6 nT and the north-south IMF component range (Bz) was +6 to -5 nT. The solar wind environment is expected to remain near background levels over 30-Aug to 1-Sep. ----------------------------------------------------------- 2A. MAGNETIC SUMMARY Geomagnetic field for Australian Region 29 Aug: G0 Estimated Indices 29 Aug : A K Australian Region 5 22111122 Cocos Island 3 12110021 Darwin 5 22111122 Townsville 5 22111122 Learmonth 4 22110122 Alice Springs 4 12111122 Gingin 4 22100122 Canberra 3 12100112 Kennaook Cape Grim 4 22101112 Hobart 3 12101111 Estimated Antarctic Regional K Indices 29 Aug : Macquarie Island 1 12000001 Casey 13 44321123 Mawson 19 33220164 Observed Regional daily pc3 Indices 29 Aug : Darwin 0 (Quiet) Townsville 0 (Quiet) Learmonth 0 (Quiet) Alice Springs 0 (Quiet) Gingin 0 (Quiet) Canberra 4 (Quiet) Hobart 15 (Quiet) Pc3 pulsations are high frequency (10-45 second period) variations of the Earths magnetic field. Daily pc3-indices are the daily sum of 20 minute pc3-indices for that station and have been shown to be well correlated with rejection of high resolution aeromagnetic survey flight-line data. NOTE: Indices may have been generated from data obtained in cooperation with the following organisations: Geoscience Australia, University of Newcastle Space Physics Group, Australian Government Antarctic Division and International Center for Space Weather Science and Education, Japan. Estimated AFr/Ap Indices 29 Aug : A Fredericksburg 5 Planetary 5 Observed AFr/Ap Indices 28 Aug : A K Fredericksburg 7 Planetary 7 22322122 2B. MAGNETIC FORECAST Date Ap Conditions 30 Aug 4 G0 31 Aug 4 G0 01 Sep 4 G0 COMMENT: G0 geomagnetic conditions were observed in the Australian region on UT day 29-Aug. G0-G2 geomagnetic conditions were observed in the Antarctic region. G0 geomagnetic conditions are expected over 30-Aug to 1-Sep. ----------------------------------------------------------- 3A. GLOBAL HF PROPAGATION SUMMARY Latitude Band Date Low Middle High 29 Aug Normal Normal Normal PCA Event : No event. 3B. GLOBAL HF PROPAGATION FORECAST Latitude Band Date Low Middle High 30 Aug Normal Normal Fair 31 Aug Normal Normal Normal-fair 01 Sep Normal Normal Normal COMMENT: HF radio propagation conditions on UT day 29-Aug were normal, with some residual polar cap absorption affecting high latitudes. HF radio propagation conditions are expected to be mostly normal over 30-Aug to 1-Sep. Shortwave fadeouts are possible. ----------------------------------------------------------- 4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY Date T index 29 Aug 112 Observed Australian Regional MUFs Cocos Island Region: No data available during local day. No data available during local night. Niue Island Region: Mostly near predicted monthly values. Northern Australian Region: Near predicted monthly values during local day. Enhanced by 25% during local night. Southern Australian Region: Mostly near predicted monthly values. Enhanced by 20% after local dawn. Antarctic Region (Casey/Davis/Mawson): Near predicted monthly values over the UT day. Monthly T index: Month T index Jul 88 Aug 96 Sep 93 4B. AUSTRALIAN REGION IONOSPHERIC FORECAST Date T index MUFs 30 Aug 115 Near predicted monthly values to 25% enhanced 31 Aug 115 Near predicted monthly values to 25% enhanced 01 Sep 115 Near predicted monthly values to 25% enhanced COMMENT: Maximum usable frequencies (MUFs) on UT day 29-Aug were near predicted values to 25% enhanced. Conditions were degraded during local night hours in Darwin. Scintillation was observed in Darwin and Weipa from 1205 to 1240 UT. MUFs are expected to be near predicted values to 25% enhanced over 30-Aug to 1-Sep. Shortwave fadeouts are possible. ----------------------------------------------------------- 5. SPACE ENVIRONMENT SUMMARY GOES satellite data for 28 Aug Daily Proton Fluence >1 MeV: 1.7e+07 Daily Proton Fluence >10 MeV: 4.4e+05 Daily Electron Fluence >2 MeV: 1.3e+07 Fluence (flux accumulation over 24hrs)/ cm2-ster-day. X-ray background: C2.9 DSCOVR Satellite Solar Wind Day Averaged Data for 28 Aug Speed: 392 km/sec Density: 3.2 p/cc Temp: 70700 K Bz: 1 nT (Courtesy Space Weather Prediction Center, Boulder USA) -----------------------------------------------------------