[Ips-dhfpr] ASWFC Daily HF Prop Report - 19 July 25 issued 2331 UT on 19 Jul 2025 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/19 JULY 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (19 JULY) 
Date   T index  Conditions    
19 Jul    95    Normal         

Flares: none.

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

PCA Event : No event.

Monthly T index:
Month  T index
Jun      79
Jul      104
Aug      102


2. FORECAST (20 JULY - 22 JULY)
Date   T index  Conditions       MUFs                              
20 Jul    85    Fair-normal      Depressed 10 to 15%/near predicted 
                                 monthly values
21 Jul    90    Normal           Near predicted monthly values    
22 Jul    90    Normal-fair      Near predicted monthly values   

COMMENT: Maximum usable frequencies (MUFs) in the Australian 
region were 20% depressed to near predicted values, with depressions 
observed during local night hours and after dawn in the northern 
Australian region. Spread F was observed during local night hours 
at Learmonth, Canberra and Hobart, indicating mildly degraded 
HF conditions. MUFs are expected to be generally near predicted values 
20-22 Jul. Degraded conditions may experienced during local night 
hours 22-23 Jul due to mild geomagnetic activity from a coronal 
hole wind stream.

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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