[Ips-whfpr] ASWFC Weekly Prop. Report (27 August 25) issued 0124 UT on 27 Aug 2025 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC WEEKLY HF PROPAGATION REPORT
ISSUED ON 27 AUGUST 2025 
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (20 AUGUST - 26 AUGUST)
Date   T index   Conditions        
20 Aug  107      Normal            
MUFS:
   Cocos Island Region:
      Enhanced by 15% during local day.
      Depressed by 35% during local night.
   Niue Island Region:
      Near predicted monthly values during local day.
      Enhanced by 25% 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 20% over the UT day.

21 Aug   93      Normal            
MUFS:
   Cocos Island Region:
      No data available. 
   Niue Island Region:
      Near predicted monthly values during local day.
      Depressed by 20% 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.

22 Aug   94      Normal            
MUFS:
   Cocos Island Region:
      No data available. 
   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.

23 Aug   95      Normal            
MUFS:
   Cocos Island Region:
      No data available. 
   Niue Island Region:
      Enhanced by 20% during local day.
      Enhanced by 45% 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.

24 Aug   86      Normal            
MUFS:
   Cocos Island Region:
      No data available. 
   Niue Island Region:
      Near predicted monthly values.
   Northern Australian Region:
      Near predicted monthly values during local day.
      Depressed by 20% during local night.
   Southern Australian Region:
      Near predicted monthly values.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

25 Aug   90      Normal            
MUFS:
   Cocos Island Region:
      No data available.
   Niue Island Region:
      Near predicted monthly values.
   Northern Australian Region:
      Mostly near predicted monthly values.
   Southern Australian Region:
      Near predicted monthly values.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

26 Aug  101      Normal            
MUFS:
   Cocos Island Region:
      No data available.
   Niue Island Region:
      Enhanced by 25% during local day.
      Enhanced by 15% during local night.
   Northern Australian Region:
      Enhanced by 15% during local day.
      Enhanced by 25% during local night.
   Southern Australian Region:
      Near predicted monthly values.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.
      Proton event in progress, increased absorption observed.

Predicted Monthly T index for August:  96

2. FORECAST (27 AUGUST - 02 SEPTEMBER) 
MUFS: MUFs are expected to be near predicted monthly values 
this week.
 
Propagation conditions: HF propagation conditions are expected
to be mostly normal this week. Spread F is possible in southern
Australian regions during local night hours. Shortwave fadeouts
are probable.

T index: 96
ASWFC SWF HF Communications Warning 77 was issued on 27 August 
and is current for 27-29 Aug.

3. OUTLOOK (03 SEPTEMBER - 03 OCTOBER)
Degraded HF propagation conditions possible:
03-10 Sep,  15-16 Sep, 30 Sep to 03 Oct.

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