[Ips-dhfpr] ASWFC Daily HF Prop Report - 15 May 25 issued 2331 UT on 15 May 2025 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/15 MAY 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (15 MAY) 
Date   T index  Conditions    
15 May    88    Normal-fair    

Flares    Max     Fadeout    Freq.  Sectors
  M2.1    1721UT  possible   lower  South American/
                                    Atlantic

MUFs:
   Cocos Island Region:
      Near predicted monthly values during local day.
      Depressed by 20% 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 35% during local night.
   Southern Australian Region:
      Near predicted monthly values during local day.
      Depressed by 15% during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 15% over the UT day.

PCA Event : No event.

Monthly T index:
Month  T index
Apr      123
May      113
Jun      111


2. FORECAST (16 MAY - 18 MAY)
Date   T index  Conditions       MUFs                              
16 May    90    Normal           Depressed 15%/near predicted 
                                 monthly values
17 May    90    Normal           Depressed 15%/near predicted 
                                 monthly values    
18 May    90    Normal-fair      Depressed 15%/near predicted 
                                 monthly values   

COMMENT: ASWFC SWF HF Communications Warning 47 was issued on 
14 May and is current for 14-16 May. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 15-May were depressed 
by 15-35% during local night and were near predicted monthly 
values during local day. Spread F was observed at Hobart and 
Brisbane during local night hours. MUFs are expected to be near 
predicted monthly values to 15% depressed over 16-18 May. Shortwave 
fadeouts are probable.

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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