[Ips-dhfpr] ASWFC Daily HF Prop Report - 25 March 24 issued 2331 UT on 25 Mar 2024 [SEC=OFFICIAL]

[Regional Warning Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/25 MARCH 2024
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (25 MARCH) 
Date   T index  Conditions    
25 Mar    94    Poor-fair      

Flares    Max     Fadeout    Freq.  Sectors
  M4.4    0644UT  possible   lower  Mid East/Indian

MUFs:
   Cocos Island Region:
      Enhanced by 20% during local day.
      Near predicted monthly values during local night.
      Enhanced by 45% after local dawn.
   Niue Island Region:
      Near predicted monthly values.
   Northern Australian Region:
      Near predicted monthly values during local day.
      Enhanced by 15% during local night.
   Southern Australian Region:
      Depressed by 25% during local day.
      Depressed by 20% during local night.
      Depressed by 20% after local dawn.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 30% over the UT day.

PCA Event : 10MeV Proton/PCA Event Began at 0805UT 23/03, Ended at 1405UT 25/03

Monthly T index:
Month  T index
Feb      138
Mar      111
Apr      112


2. FORECAST (26 MARCH - 28 MARCH)
Date   T index  Conditions       MUFs                              
26 Mar   100    Normal-fair      Near predicted monthly values/depressed 
                                 5 to 10%
27 Mar   110    Normal           Near predicted monthly values    
28 Mar   120    Normal           Near predicted monthly values   

COMMENT: ASWFC SWF HF Communications Warning 31 was issued on 
23 March and is current for 24-26 Mar. ASWFC HF Communications 
Warning 32 was issued on 24 March and is current for 24-26 Mar. 
Maximum usable frequencies (MUFs) on UT day 25-Mar were near 
predicted monthly values in the northern Australian region, with 
enhancements observed during local night. MUFs in the southern 
Australian region were depressed throughout 25-Mar, with some 
sign of recovery near the end of the UT-day. Sporadic E was observed 
at Brisbane and Canberra and spread F was observed at Canberra 
and Hobart, disrupting HF communication conditions. A polar cap 
absorption event (PCA) was present in the first half of 25-Mar 
and affected ionospheric conditions in the polar regions. MUFs 
are expected to be near predicted monthly values over 26-28 Mar, 
with mild depressions possible in the southern Australian region 
as conditions ease following recent geomagnetic activity. 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