[Ips-dhfpr] ASWFC Daily HF Prop Report - 09 December 25 issued 2330 UT on 09 Dec 2025 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/09 DECEMBER 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (09 DECEMBER) 
Date   T index  Conditions    
09 Dec   154    Normal         

Flares    Max     Fadeout    Freq.  Sectors
  M2.0    0058UT  possible   lower  West Pacific
  M1.0    0730UT  possible   lower  Mid East/Indian
  M1.6    0747UT  possible   lower  Mid East/Indian
  M1.5    1514UT  possible   lower  South American/
                                    Atlantic

MUFs:
   Cocos Island Region:
      Enhanced by 30% during local day.
      Enhanced by 50% during local night.
      Enhanced by 25% after local dawn.
   Niue Island Region:
      Near predicted monthly values during local day.
      Enhanced by 15% during local night.
   Northern Australian Region:
      Enhanced by 15% during local day.
      Enhanced by 20% during local night.
      Enhanced by 25% after local dawn.
   Southern Australian Region:
      Enhanced by 25% during local day.
      Enhanced by 20% during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

PCA Event : No event.

Monthly T index:
Month  T index
Nov      103
Dec      89
Jan      89


2. FORECAST (10 DECEMBER - 12 DECEMBER)
Date   T index  Conditions       MUFs                              
10 Dec   120    Normal-fair      10 to 15% above predicted monthly 
                                 values
11 Dec   120    Normal-fair      10 to 15% above predicted monthly 
                                 values    
12 Dec   120    Normal-fair      10 to 15% above predicted monthly 
                                 values   

COMMENT: ASWFC Preliminary HF Communications Warning 117 was 
issued on 6 December and is current for 9-10 Dec. ASWFC SWF HF 
Communications Warning 120 was issued on 9 December and is current 
for 9-11 Dec. Maximum usable frequencies (MUFs) in the Australian 
region on UT day 9-Dec were near predicted values to 25% enhanced. 
Sporadic-E was observed at Niue. Mild spread F was observed at 
Hobart during local night hours. Due to the failed occurrence 
of CME induced geomagnetic storm activity on 09-Dec the middle 
latitude Australian ionosphere is now generally expected to remain 
at near predicted monthly values to 15% enhanced over 10-12 Dec. 
The southern Australian region may experience mildly degraded 
HF conditions during local night hours 11-12 Dec. Minor shortwave 
fadeouts were observed 09/0043-0129UT and 09/0135-0142UT. Minor 
shortwave fadeouts are possible.

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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