[Ips-dsgr] ASWFC Daily Report - 28 October 25 issued 2330 UT on 28 Oct 2025 [SEC=OFFICIAL]
Australian Space Weather Forecasting Centre
aswfc at bom.gov.au
Wed Oct 29 10:30:51 AEDT 2025
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/28 OCTOBER 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 28 OCTOBER AND FORECAST FOR 29 OCTOBER - 31 OCTOBER
STATUS INDICATORS SOL:GREEN MAG:** RED ** ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 28 Oct: R0
Flares: none.
Observed 10.7 cm flux/Equivalent Sunspot Number for 28 Oct: 122/75
1B. SOLAR FORECAST
29 Oct 30 Oct 31 Oct
Activity R0 R0 R0
Fadeouts None expected None expected None expected
10.7cm/SSN 120/72 125/78 130/84
COMMENT: Solar activity on UT day 28-Oct was at the R0 level,
with a single C1.7 flare observed at 28/1626UT. There are currently
seven numbered sunspot regions visible on the solar disk and
two unnumbered regions. AR4266 (N16W22, beta) and AR4267 (N08E02,
beta) both showed development over the UT day and AR4267 was
responsible for the C1.7 flare at 28/1626UT. An unnumbered region
has developed on the disk at around N11W03 with beta magnetic
characteristics and an additional unnumbered region has rotated
onto the solar disk at around N12E44 with alpha magnetic characteristics.
All other regions are either stable or in decay. Solar activity
is expected to be at the R0 level over 29-31 Oct. S0 solar radiation
conditions were observed on UT day 28-Oct. S0 solar radiation
conditions are expected over 29-31 Oct. No Earth-directed CMEs
have been observed on UT day 28-Oct. A filament lift off is visible
in H-Alpha, SDO and GOES SUVI imagery from 28/0234UT at around
N20E40. There is no associated CME visible in available coronagraph
imagery. A broad, east directed CME is visible in SOHO coronagraph
imagery from 28/1536UT. Coronal dimming over the eastern limb
is visible from 28/1521UT in GOES SUVI imagery. This CME is considered
a far side event and not geoeffective. The solar wind speed on
UT day 28-Oct increased, mostly ranging between 360 to 485 km/s
and is currently near 460 km/s. The peak total interplanetary
magnetic field strength (IMF, Bt) was 13 nT and the North-South
IMF component (Bz) range was -11 to +8 nT. A sustained period
of southward Bz (-Bz) began at 28/1600UT and ended at 28/2220UT.
It appears the Earth has entered an expected coronal hole high
speed wind stream, although the impacts of this wind stream have
not yet been as strong as anticipated. The solar wind speed is
expected to continue to increase over the 29-30 Oct due to ongoing
coronal hole high speed wind effects. A decline is possible on
31-Oct.
-----------------------------------------------------------
2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 28 Oct: G0
Estimated Indices 28 Oct : A K
Australian Region 13 23324233
Cocos Island 10 22223233
Darwin 14 22324234
Townsville 13 23324233
Learmonth 17 33325233
Alice Springs 13 23324233
Gingin 16 32225234
Canberra 13 13324233
Kennaook Cape Grim 13 23324233
Hobart 14 13424233
Estimated Antarctic Regional K Indices 28 Oct :
Macquarie Island 22 13336342
Casey 21 35443233
Mawson 40 44434375
Observed Regional daily pc3 Indices 28 Oct :
Darwin 0 (Quiet)
Townsville 0 (Quiet)
Learmonth 0 (Quiet)
Alice Springs 2 (Quiet)
Gingin 11 (Quiet)
Canberra 7 (Quiet)
Hobart 22 (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 28 Oct : A
Fredericksburg 16
Planetary 20
Observed AFr/Ap Indices 27 Oct : A K
Fredericksburg 4
Planetary 6 1111 1223
2B. MAGNETIC FORECAST
Date Ap Conditions
29 Oct 30 G1
30 Oct 22 G0-G1
31 Oct 8 G0
COMMENT: ASWFC Geomagnetic Warning 82 was issued on 27 October
and is current for 28-29 Oct. Mostly G0 geomagnetic conditions
were observed in the Australian region on UT day 28-Oct with
a period of G1 conditions observed at Learmonth and Gingin. G1-G3
conditions were observed in the Antarctic region. G1 geomagnetic
conditions are expected on 29-Oct, G0-G1 conditions are expected
on 30-Oct due to ongoing coronal hole high speed wind stream
effects. G0 conditions are expected on 31-Oct
-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
28 Oct Normal Normal Normal
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
29 Oct Fair-normal Fair-normal Fair
30 Oct Fair Fair Fair
31 Oct Normal Normal Normal-fair
COMMENT: HF radio propagation conditions on UT day 28-Oct were
mostly normal with mild degradations observed at the end of the
UT day. Mostly fair conditions are expected over 29-30 Oct due
to anticipated geomagnetic activity. Mostly normal conditions
are expected on 31-Oct.
-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
28 Oct 113
Observed Australian Regional MUFs
Cocos Island Region:
Near predicted monthly values during local day.
Enhanced by 20% during local night.
Niue Island Region:
Near predicted monthly values during local day.
Enhanced by 15% during local night.
Northern Australian Region:
Near predicted monthly values.
Southern Australian Region:
Enhanced by 15% during local day.
Near predicted monthly values during local night.
Depressed by 20% after local dawn.
Antarctic Region (Casey/Davis/Mawson):
Near predicted monthly values over the UT day.
Monthly T index:
Month T index
Sep 109
Oct 89
Nov 89
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
29 Oct 90 Near predicted monthly values/depressed 5 to
15%
30 Oct 75 Near predicted monthly values/depressed 5 to
15%
31 Oct 90 Near predicted monthly values
COMMENT: Maximum usable frequencies (MUFs) in the Australian
region on UT day 28-Oct were near predicted monthly values with
enhancements of up to 15% observed during local day and depressions
of up to 20% during local dawn in the southern Australian region.
Spread F was observed at Hobart during local night hours and
mild sporadic E was observed at Townsville during local night
hours. MUFs are expected to be near predicted monthly values
over 29-31 Oct, with a chance of mild depressions in the southern
Australian region due to anticipated geomagnetic activity.
-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 27 Oct
Daily Proton Fluence >1 MeV: 3.9E+05
Daily Proton Fluence >10 MeV: 1.8E+04
Daily Electron Fluence >2 MeV: 2.20E+07 (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 4%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: B4.3
DSCOVR Satellite Solar Wind Day Averaged Data for 27 Oct
Speed: 364 km/sec Density: 5.8 p/cc Temp: 45500 K Bz: 2 nT
(Courtesy Space Weather Prediction Center, Boulder USA)
-----------------------------------------------------------
Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au
More information about the ips-dsgr
mailing list