[Ips-whfpr] ASWFC Weekly Prop. Report (15 October 25) issued 0054 UT on 15 Oct 2025 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC WEEKLY HF PROPAGATION REPORT
ISSUED ON 15 OCTOBER 2025 
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (08 OCTOBER - 14 OCTOBER)
Date   T index   Conditions        
08 Oct  113      Fair-normal       
MUFS:
   Cocos Island Region:
      Enhanced by 25% during local day.
      Near predicted monthly values during local night.
   Niue Island Region:
      Enhanced by 25% during local day.
      Enhanced by 15% during local night.
   Northern Australian Region:
      Enhanced by 15% during local day.
      Near predicted monthly values during local night.
   Southern Australian Region:
      Near predicted monthly values.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 15% over the UT day.

09 Oct  111      Normal            
MUFS:
   Cocos Island Region:
      Enhanced by 40% during local day.
      Near predicted monthly values during local night.
   Niue Island Region:
      Enhanced by 50% during local day.
      Enhanced by 25% during local night.
   Northern Australian Region:
      Enhanced by 20%.
   Southern Australian Region:
      Near predicted monthly values.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

10 Oct  119      Normal            
MUFS:
   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  112      Normal-fair       
MUFS:
   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   71      Normal-fair       
MUFS:
   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   82      Fair-normal       
MUFS:
   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  100      Fair-normal       
MUFS:
   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.

Predicted Monthly T index for October:  89

Comment: Depressed MUFs for the Southern Australian region
were observed on 12-Oct, possibly in association with
mild geomagnetic activity due to a coronal hole wind
stream. There are two moderately large and magnetically 
complex solar regions on the solar disk. Solar flare 
activity is expected to increase in coming days.


2. FORECAST (15 OCTOBER - 21 OCTOBER) 
MUFS: Southern Australian regional MUFs are expected to be 
depressed 15% at times from late 15-Oct to 17-Oct, due to 
expected G1 geomagnetic activity associated with three 
anticipated weak CME arrivals during this period. MUFs near 
predicted monthly values on other days. Northern Australian
region MUFs expected to remain near predicted monthly
values to 15% enhanced.

Propagation conditions: Fair from late 15-Oct to 17-Oct for the 
southern Australian region. Otherwise normal. SWFs probable first
half of the week. 

T index: 70 on 16-17 Oct, 95 on other days.
ASWFC SWF HF Communications Warning 94 was issued on 15 October 
and is current for 15-17 Oct.

3. OUTLOOK (22 OCTOBER - 21 NOVEMBER)
Degraded HF propagation conditions possible:
28-30 Oct,  8-9 Nov

PLEASE NOTE:
Space weather conditions can frequently be determined by short 
timescale events that cannot be forecast a week in advance,
particularly at solar maximum.

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