[Ips-dhfpr] ASWFC Daily HF Prop Report - 17 May 26 issued 2330 UT on 17 May 2026 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/17 MAY 2026
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (17 MAY) 
Date   T index  Conditions    
17 May    48    Normal         

Flares    Max     Fadeout    Freq.  Sectors
  M1.4    0339UT  possible   lower  E. Asia/Aust.

MUFs:
   Cocos Island Region:
      No data available during local day.
      No data available during local night.
   Niue Island Region:
      Depressed by 15% during local day.
      Depressed by 35% during local night.
   Northern Australian Region:
      Near predicted monthly values during local day.
      Depressed by 15% during local night.
   Southern Australian Region:
      Depressed by 20% during local day.
      Depressed by 20% during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 20% over the UT day.

PCA Event : No event.

Monthly T index:
Month  T index
Apr      74
May      71
Jun      68


2. FORECAST (18 MAY - 20 MAY)
Date   T index  Conditions       MUFs                              
18 May    45    Normal-fair      Depressed 15%/near predicted 
                                 monthly values
19 May    45    Normal-fair      Depressed 15%/near predicted 
                                 monthly values    
20 May    54    Normal           Near predicted monthly values   

COMMENT: Maximum Usable Frequencies (MUFs) were near predicted 
monthly values in the northern Australian region during local 
day, but depressed by up to 15% during local night. MUFs were 
depressed by up to 20% in the southern Australian region throughout 
the day. Significant spread-F was observed at Hobart and Canberra 
during local night hours. MUFs are expected to be near predicted 
monthly values in the first half of 18-May, with depressions 
of up to 15% expected possible from late on 18-May through 19-May 
due to anticipated geomagnetic activity. Conditions are expected 
to recover towards predicted monthly values on 20-May.

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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