[Ips-dsgr] ASWFC Daily Report - 25 October 26 issued 2330 UT on 25 Oct 2026 [SEC=OFFICIAL]

Mon Oct 26 10:30:51 AEDT 2026

SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/25 OCTOBER 2026
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 25 OCTOBER AND FORECAST FOR 26 OCTOBER - 28 OCTOBER
STATUS INDICATORS SOL:GREEN   MAG:GREEN     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 25 Oct:  R0

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 25 Oct:  89/33

1B. SOLAR FORECAST
             26 Oct             27 Oct             28 Oct
Activity     R0                 R0                 R0
Fadeouts     None expected      None expected      None expected
10.7cm/SSN    88/32              84/26              84/26

COMMENT: Solar flare activity on UT day 25-Oct was at the R0 
level, with no significant flaring activity. There is currently 
one numbered sunspot region visible on the disk and three unnumbered 
regions. Active Region (AR) 4560 (N13W78, beta) is the only numbered 
region on the disk and is currently rotating over the western 
limb. An unnumbered region recently appeared near S09W62 (beta) 
and has shown mild spot development. A second unnumbered region 
is visible near S15E63 (alpha) which has exhibited mild spot 
growth. A third unnumbered region near S17W28 (beta) has shown 
some decay. Solar flare activity is expected to be at the R0 
level over 26-28 Oct. S0 solar radiation storm conditions were 
observed on UT day 25-Oct. S0 solar radiation storm conditions 
are expected over 26-28 Oct. No Earth-directed coronal mass ejections 
(CMEs) have been observed. The solar wind speed on UT day 25-Oct 
decreased, ranging between 370 and 340 km/s, and is currently 
near 345 km/s. The peak total interplanetary magnetic field strength 
(IMF, Bt) was 6 nT and the north-south IMF component (Bz) ranged 
between -3 to +4 nT. The solar wind speed is expected to remain 
at background levels over 26-28 Oct.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 25 Oct: G0

Estimated Indices 25 Oct : A   K           
   Australian Region       1   11011001
      Cocos Island         0   01001000
      Darwin               2   11011012
      Townsville           2   11011111
      Learmonth            2   11011002
      Alice Springs        1   11011001
      Gingin               1   11011001
      Canberra             1   11011001
      Kennaook Cape Grim   1   11011001
      Hobart               1   01011001    

Estimated Antarctic Regional K Indices 25 Oct :
      Casey                8   34222011
      Mawson              15   22112155

Observed Regional daily pc3 Indices 25 Oct : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               0   (Quiet)
      Canberra             0   (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 25 Oct : A 
           Fredericksburg         4
           Planetary              4                         

Observed AFr/Ap Indices 24 Oct :  A   K
           Fredericksburg         3
           Planetary              5   2112 2221     

2B. MAGNETIC FORECAST 
Date      Ap    Conditions
26 Oct     8    G0
27 Oct     6    G0
28 Oct     6    G0

COMMENT: G0 geomagnetic conditions were observed in the Australian 
region and at the planetary level on UT day 25-Oct. Mostly G0 
geomagnetic conditions were observed in the Antarctic region, 
with an isolated period of G1 observed at Mawson. G0 planetary 
geomagnetic conditions are expected over 26-28 Oct.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
25 Oct      Fair           Normal-fair    Normal-fair    

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
26 Oct      Normal         Normal         Normal-fair
27 Oct      Normal         Normal         Normal
28 Oct      Normal         Normal         Normal

COMMENT: Global high-frequency (HF) radio propagation conditions 
were mostly fair over UT day 25-Oct, with most degraded conditions 
observed in northern hemisphere regions. HF propagation conditions 
are forecast to be mostly normal over 26-28 Oct.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY

Date   T index
25 Oct    33

Observed Australian Regional MUFs
   Cocos Island Region:
      No data available during local day.
      No data available during local night.
   Niue Island Region:
      Depressed by 15% during local day.
      Near predicted monthly values during local night.
   Northern Australian Region:
      Depressed by 20% during local day.
      Depressed by 15% during local night.
   Southern Australian Region:
      Depressed by 15% during local day.
      Near predicted monthly values during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

Monthly T index:
Month  T index
Sep      61
Oct      60
Nov      58

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
26 Oct    40    Near predicted monthly values
27 Oct    50    Near predicted monthly values
28 Oct    50    Near predicted monthly values

COMMENT: ASWFC HF Communications Warning 94 was issued on 24 
October and is current for 25-Oct. Maximum Usable Frequencies 
(MUFs) on UT day 25-Oct were depressed by 15-20% in northern 
Australia regions. MUFs in southern Australia were near predicted 
monthly values during local night and 15% depressed during local 
day. Spread F was observed at Hobart and Perth during local night 
hours. MUFs are forecast to be mostly near predicted monthly 
values over 26-28 Oct.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 24 Oct
       Daily Proton Fluence >1 MeV:   1.1E+05
       Daily Proton Fluence >10 MeV:  2.2E+04
       Daily Electron Fluence >2 MeV: 1.16E+08   (moderate fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability:11%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: B4.0

Solar Wind Day Averaged Data for 24 Oct
Speed: 395 km/sec  Density:    2.1 p/cc  Temp:    84700 K  Bz:  -1 nT

(Courtesy Space Weather Prediction Center, Boulder USA)
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Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au