[Ips-dhfpr] ASWFC Daily HF Prop Report - 19 April 26 issued 2330 UT on 19 Apr 2026 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/19 APRIL 2026
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (19 APRIL) 
Date   T index  Conditions    
19 Apr    71    Poor           

Flares: none.

MUFs:
   Cocos Island Region:
      Near predicted monthly values during local day.
      Depressed by 35% during local night.
   Niue Island Region:
      Mostly near predicted monthly values.
      Depressed by 25% after local dawn.
   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.
      Depressed by 20% after local dawn.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 25% over the UT day.

PCA Event : No event.

Monthly T index:
Month  T index
Mar      92
Apr      83
May      81


2. FORECAST (20 APRIL - 22 APRIL)
Date   T index  Conditions       MUFs                              
20 Apr    65    Fair-poor        Depressed 15 to 20%/near predicted 
                                 monthly values
21 Apr    75    Normal-fair      Near predicted monthly values    
22 Apr    80    Normal           Near predicted monthly values   

COMMENT: ASWFC HF Communications Warning 37 was issued on 19 
April and is current for 19-20 Apr. Maximum Usable Frequencies 
(MUFs) in the Australian region on UT day 19-Apr were initially 
near predicted monthly values, but became depressed over the 
UT day due to ongoing geomagnetic activity. Depressions of up 
to 35% were recorded across the Northern Australian region and 
at the Cocos Islands during local night and dawn hours. Depressions 
of 20-25% were also reported across the Southern Australian region, 
as well as the Antarctic region and Niue Island. Strong spread-F 
was present in the southern Australian region, and sporadic-E 
was recorded at Canberra and Norfolk Island. MUFs are expected 
to remain depressed by 15-20% for UT day 20-Apr due to the ongoing 
geomagnetic activity, before trending towards predicted monthly 
values over 21-22 Apr.

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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