[Ips-dhfpr] ASWFC Daily HF Prop Report - 01 September 23 issued 2330 UT on 01 Sep 2023 [SEC=OFFICIAL]

[Regional Warning Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/01 SEPTEMBER 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (01 SEPTEMBER) 
Date   T index  Conditions    
01 Sep   117    Normal         

Flares    Max     Fadeout    Freq.  Sectors
  M1.1    0319UT  possible   lower  E. Asia/Aust.

MUFs:
   Cocos Island Region:
      Near predicted monthly values during local day.
      Depressed by 15% during local night.
   Niue Island Region:
      Enhanced by 15-40%.
   Northern Australian Region:
      Enhanced by 20%.
   Southern Australian Region:
      Enhanced by 15-20%.
   Antarctic Region (Casey/Davis/Mawson):
      Enhanced by 15% over the UT day.

PCA Event : 10MeV Proton/PCA Event Began at 0425UT 01/09, Ended at 2000UT 01/09

Monthly T index:
Month  T index
Aug      115
Sep      84
Oct      81


2. FORECAST (02 SEPTEMBER - 04 SEPTEMBER)
Date   T index  Conditions       MUFs                              
02 Sep   105    Normal-fair      Initially near predicted monthly 
                                 values to 15% enhanced
03 Sep    60    Fair             Depressed 15 to 20%/near predicted 
                                 monthly values    
04 Sep    75    Fair-normal      Depressed 10 to 15%/near predicted 
                                 monthly values   

COMMENT: ASWFC Preliminary HF Communications Warning 84 was issued 
on 31 August and is current for 3-4 Sep. ASWFC SWF HF Communications 
Warning 85 was issued on 1 September and is current for 1-3 Sep. 
Maximum usable frequencies (MUFs) on UT day 01-Sep were near 
predicted values to 20% enhanced in the Australian region. Scintillation 
was observed at Niue and Weipa from 01/1200-1300UT. A minor fadeout 
only impacting the ionospheric E region was observed in association 
with the M1.2 flare. MUFs are initially expected to be near predicted 
values on 02-Sep to 15% enhanced, becoming 15-20% depressed on 
03-Sep due to anticipated geomagnetic activity. Depending on 
geomagnetic storm onset time and magnitude depressions may extend 
into 04-Sep. Degraded HF conditions are likely during local night 
hours for southern Australian region 02-Sep and 03-Sep.

----------------------------------------------------------
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