[Ips-dhfpr] ASWFC Daily HF Prop Report - 22 April 26 issued 2330 UT on 22 Apr 2026 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/22 APRIL 2026
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (22 APRIL) 
Date   T index  Conditions    
22 Apr    47    Fair           

Flares: none.

MUFs:
   Cocos Island Region:
      No data available during local day.
      No data available during local night.
   Niue Island Region:
      Near predicted monthly values during local day.
      Depressed by 35% during local night.
      Depressed by 20% after local dawn.
   Northern Australian Region:
      Near predicted monthly values during local day.
      Depressed by 25% during local night.
   Southern Australian Region:
      Depressed by 20% during local day.
      Depressed by 25% 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
Mar      92
Apr      83
May      81


2. FORECAST (23 APRIL - 25 APRIL)
Date   T index  Conditions       MUFs                              
23 Apr    58    Fair-normal      Depressed 15 to 20%/near predicted 
                                 monthly values
24 Apr    65    Normal-fair      Near predicted monthly values    
25 Apr    75    Normal           Near predicted monthly values   

COMMENT: ASWFC HF Communications Warning 40 was issued on 22 
April and is current for 23 Apr only. Maximum Usable Frequencies 
(MUFs) in the Australian region were depressed by 20-25% over 
UT day 22-Apr, with MUFs near predicted values during local daylight 
hours in the Northern Australian region. Spread-F was observed 
in multiple sites in the Southern Australian region. Depressions 
of up to 15% were reported in the Antarctic region, with depressions 
up to 35% at Niue Island. MUFs are forecast to trend toward predicted 
monthly values over 23-Apr, and remain near predicted values 
over 24-25 Apr.

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