[Ips-dhfpr] ASWFC Daily HF Prop Report - 29 September 25 issued 2339 UT on 29 Sep 2025 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/29 SEPTEMBER 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (29 SEPTEMBER) 
Date   T index  Conditions    
29 Sep   130    Normal-fair    

Flares    Max     Fadeout    Freq.  Sectors
  M3.6    0145UT  possible   lower  West Pacific
  M1.0    1115UT  possible   lower  European
  M1.1    1139UT  possible   lower  European
  M1.0    1159UT  possible   lower  European

MUFs:
   Cocos Island Region:
      Near predicted monthly values during local day.
      Enhanced by 15% during local night.
   Niue Island Region:
      Enhanced by 20-30%.
   Northern Australian Region:
      Enhanced by 15-25%.
   Southern Australian Region:
      Near predicted monthly values during local day.
      Enhanced by 20% during local night.
      Depressed by 15-30% after local dawn.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 15% over the UT day.

PCA Event : No event.

Monthly T index:
Month  T index
Aug      96
Sep      92
Oct      90


2. FORECAST (30 SEPTEMBER - 02 OCTOBER)
Date   T index  Conditions       MUFs                              
30 Sep    75    Fair-normal      Depressed 15 to 20%/near predicted 
                                 monthly values
01 Oct   130    Normal           Near to 15% above predicted 
                                 monthly values    
02 Oct   130    Normal           Near to 15% above predicted 
                                 monthly values   

COMMENT: ASWFC SWF HF Communications Warning 86 was issued on 
28 September and is current for 29 Sep to 1 Oct. Maximum usable 
frequencies (MUFs) in the Australian region on UT day 29-Sep 
were variable. Northern Australian region were generally enhanced 
15-25%. MUFs in the southern Australian region were initially 
near to 20% above predicted monthly values, becoming depressed 
by 15-30% after local dawn this morning, following overnight 
geomagnetic activity and are expected to slowly recover today. 
Spread F was observed at Hobart over night. Equatorial range 
spread F was observed at Cocos Island and Niue. Equatorial ionospheric 
scintillation was observed 29/0717-1130UT. A brief fadeout impacting 
only the lower HF frequencies was observed 29/0143-0149UT. Northern 
region MUFs are expected to be near predicted monthly values 
to 15% enhanced for 30-Sep. MUFs are expected to be near predicted 
values to 15% enhanced over 01-02 Oct.

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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