[Ips-wsgr] ASWFC Weekly Solar and Geophysical Report (17 October 25) issued 0131 UT on 17 Oct 2025 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC WEEKLY SOLAR AND GEOPHYSICAL REPORT 
ISSUED ON 17 OCTOBER 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx

1. SUMMARY (10 OCTOBER - 16 OCTOBER)
Date     10    11    12    13    14    15    16
10cm    121   131   143   141   154   162   161
AFr       9    15    18    17     6     9  ( 14)
Aaus      4    12    16    15     5     7  (  3)
T       119   112    71    82   100   108   113

Solar:        Solar flare activity
Geomagnetic:  Geomagnetic activity observed for Australian region.
Frequencies:  Australian ionospheric F2 critical frequencies

10 Oct 
Solar:        R0
Geomagnetic:  G0
Frequencies:  
   Cocos Island Region:
      Enhanced by 40% during local day.
      Enhanced by 35% during local night.
   Niue Island Region:
      Enhanced by 45% during local day.
      Near predicted monthly values during local night.
   Northern Australian Region:
      Enhanced by 25% during local day.
      Enhanced by 25% during local night.
   Southern Australian Region:
      Enhanced 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.

11 Oct 
Solar:        R0
Geomagnetic:  G0
Frequencies:  
   Cocos Island Region:
      Enhanced by 30% during local day.
      Enhanced by 40% during local night.
   Niue Island Region:
      Mostly near predicted monthly values.
      Depressed by 20% after local dawn.
   Northern Australian Region:
      Enhanced by 20% during local day.
      Enhanced by 25% during local night.
   Southern Australian Region:
      Enhanced by 20% during local day.
      Near predicted monthly values during local night.
      Depressed by 25% after local dawn.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

12 Oct 
Solar:        R0
Geomagnetic:  G0
Frequencies:  
   Cocos Island Region:
      Near predicted monthly values.
   Niue Island Region:
      Near predicted monthly values during local day.
      Depressed by 15% during local night.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian Region:
      Depressed by 25% during local day.
      Near predicted monthly values during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 15% over the UT day.

13 Oct 
Solar:        R1, with an M1.9 at 0527UT, an M2.7 at 0919UT, 
              and an M1.3 at 1319UT
Geomagnetic:  G0
Frequencies:  
   Cocos Island Region:
      Near predicted monthly values.
   Niue Island Region:
      Enhanced by 20% during local day.
      Near predicted monthly values during local night.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian Region:
      Near predicted monthly values.
      Perth depressed by 30% during the local day.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 15% over the UT day.

14 Oct 
Solar:        R1, with an M2.0 at 0041UT, an M2.0 at 1247UT, 
              and an M3.1 at 2036UT
Geomagnetic:  G0
Frequencies:  
   Cocos Island Region:
      Enhanced by 20% during local day.
      Enhanced by 25% during local night.
   Niue Island Region:
      Enhanced by 15% during local day.
      Near predicted monthly values during local night.
   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.

15 Oct 
Solar:        R1, with an M4.8 at 0415UT, an M3.7 at 0718UT, 
              an M1.1 at 1410UT, and an M2.7 at 2228UT
Geomagnetic:  G0
Frequencies:  
   Cocos Island Region:
      Near predicted monthly values during local day.
      Enhanced by 15% during local night.
   Niue Island Region:
      Enhanced by 45% during local day.
      Enhanced by 40% during local night.
   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.

16 Oct 
Solar:        R1, with an M2.7 at 2228UT, an M1.3 at 1408UT, 
              an M1.1 at 1916UT, and an M1.0 at 2319UT
Geomagnetic:  G0
Frequencies:  
   Cocos Island Region:
      Enhanced by 25% during local day.
      Enhanced by 50% during local night.
   Niue Island Region:
      Near predicted monthly values during local day.
      Enhanced by 20% during local night.
   Northern Australian Region:
      Near predicted monthly values during local day.
      Enhanced by 20% during local night.
   Southern Australian Region:
      Near predicted monthly values during local day.
      Enhanced by 15% during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

 
2. FORECAST (17 OCTOBER - 23 OCTOBER)
Solar: 
R1-R2 conditions are expected over 17-23 Oct. Returning region AR4232 that has 
previously produced R1-R2 level flares, may return to the visible disk this
week.


Geomagnetic:  
G0-G1 geomagnetic conditions are expected for 17-Oct due to the possible late
arrival of two CMEs.
G0 with a chance of G1 are expected on 18-Oct. 
G0-G1 geomagnetic conditions are expected on 19-22 Oct as an equatorial 
coronal hole becomes geoeffective.
G0 with a chance of G1 are expected on 23 Oct.

Frequencies:  
MUFs are expected to be near predicted monthly values with mild 
depressions possible due to minor geomagnetic activity.  
Shortwave fadeouts are probable.


For an explanation of some of the terms in this report, go to
https://www.sws.bom.gov.au, and follow links to Educational->
Glossary on Solar Terrestrial Terms.

Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au