Daily Report

(last updated 01 Aug 2025 23:32 UT)

SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT ISSUED AT 2330UT/01 AUGUST 2025 FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE SUMMARY FOR 01 AUGUST AND FORECAST FOR 02 AUGUST - 04 AUGUST STATUS INDICATORS SOL:GREEN MAG:GREEN ION: GREEN ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx ----------------------------------------------------------- 1A. SOLAR SUMMARY Activity 01 Aug: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 01 Aug: 146/100 1B. SOLAR FORECAST 02 Aug 03 Aug 04 Aug Activity R0, chance R1 R0, chance R1 R0, chance R1 Fadeouts None expected None expected None expected 10.7cm/SSN 145/99 145/99 140/94 COMMENT: Solar activity on UT day 01-Aug was at the R0 level, with several low level C-class flares observed. There are currently eight numbered sunspot regions visible on the solar disk. AR4167 (N11W20, beta) is the largest region on the disk and has shown spot growth over the UT day. AR4155 (S10W46, beta) has shown mild growth in its trailer spots. All other sunspot regions are either stable or in decay. Solar activity is expected to be at the R0 level over 02-04 Aug, with a chance of R1. S0 solar proton conditions were observed on UT day 01-Aug. S0 solar proton conditions are expected over 02-04 Aug. No Earth-directed CMEs have been observed. The solar wind speed on UT day 01-Aug increased, ranging from 440 to 515 km/s and is currently near 490 km/s. The peak total interplanetary magnetic field strength (IMF, Bt) was 7 nT and the north-south IMF component (Bz) range was -7 to +6 nT. The solar wind speed is expected to decline toward background levels over 02-03 Aug. A mild increase in the solar wind is possible on 04-Aug due to a narrow equatorial coronal hole. ----------------------------------------------------------- 2A. MAGNETIC SUMMARY Geomagnetic field for Australian Region 01 Aug: G0 Estimated Indices 01 Aug : A K Australian Region 7 22213122 Cocos Island 7 22212123 Darwin 8 23223122 Townsville 9 23223123 Learmonth 10 22224123 Alice Springs 7 12223122 Gingin 9 22214123 Canberra 6 12213122 Kennaook Cape Grim 8 12214122 Hobart 6 12213122 Estimated Antarctic Regional K Indices 01 Aug : Macquarie Island 9 12125012 Casey 15 34334123 Mawson 43 34434367 Observed Regional daily pc3 Indices 01 Aug : Darwin 0 (Quiet) Townsville 0 (Quiet) Learmonth 0 (Quiet) Alice Springs 0 (Quiet) Gingin 38 (Quiet to unsettled) Canberra 21 (Quiet to unsettled) Hobart 40 (Quiet to unsettled) 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 01 Aug : A Fredericksburg 13 Planetary 14 Observed AFr/Ap Indices 31 Jul : A K Fredericksburg 10 Planetary 11 ---- ---- 2B. MAGNETIC FORECAST Date Ap Conditions 02 Aug 5 G0 03 Aug 5 G0 04 Aug 6 G0 COMMENT: G0 geomagnetic conditions were observed in the Australian region on UT day 01-Aug. Mostly G0-G1 geomagnetic conditions were observed in the Antarctic region, with isolated periods of G2 and G3 observed at Mawson. G0 geomagnetic conditions are expected over 02-04 Aug. ----------------------------------------------------------- 3A. GLOBAL HF PROPAGATION SUMMARY Latitude Band Date Low Middle High 01 Aug Normal Normal Normal-fair PCA Event : No event. 3B. GLOBAL HF PROPAGATION FORECAST Latitude Band Date Low Middle High 02 Aug Normal Normal Normal 03 Aug Normal Normal Normal 04 Aug Normal Normal Normal COMMENT: HF radio propagation conditions on UT day 01-Aug were mostly normal, with periods of fair conditions at high latitudes. HF radio propagation conditions are expected to be mostly normal over 02-04 Aug. ----------------------------------------------------------- 4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY Date T index 01 Aug 94 Observed Australian Regional MUFs Cocos Island Region: Near predicted monthly values during local day. Depressed by 20% during local night. Niue Island Region: Near predicted monthly values. Northern Australian Region: Near predicted monthly values. Southern Australian Region: Near predicted monthly values. 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 02 Aug 95 Near predicted monthly values 03 Aug 95 Near predicted monthly values 04 Aug 95 Near predicted monthly values COMMENT: Maximum usable frequencies (MUFs) in the Australian region on UT day 01-Aug were near predicted monthly values. Spread F was observed during local night hours at Hobart. MUFs are expected to be near predicted monthly values over 02-04 Aug. ----------------------------------------------------------- 5. SPACE ENVIRONMENT SUMMARY GOES satellite data for 31 Jul Daily Proton Fluence >1 MeV: 3.5E+05 Daily Proton Fluence >10 MeV: 1.6E+04 Daily Electron Fluence >2 MeV: 3.40E+07 (normal fluence) Electron Fluence Daily Deep Dielectric Discharge Probability: 5% Fluence (flux accumulation over 24hrs)/ cm2-ster-day. X-ray background: B8.1 DSCOVR Satellite Solar Wind Day Averaged Data for 31 Jul Speed: 434 km/sec Density: 2.5 p/cc Temp: 95700 K Bz: 0 nT (Courtesy Space Weather Prediction Center, Boulder USA) -----------------------------------------------------------