[Ips-dhfpr] ASWFC Daily HF Prop Report - 18 November 23 issued 2330 UT on 18 Nov 2023 [SEC=OFFICIAL]

[Regional Warning Centre]

SUBJ: ASWFC DAILY HF PROPAGATION REPORT
ISSUED AT 2330UT/18 NOVEMBER 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECAST CENTRE
AUSTRALIAN REGION SUMMARY AND FORECAST

1. SUMMARY (18 NOVEMBER) 
Date   T index  Conditions    
18 Nov   118    Fair           

Flares    Max     Fadeout    Freq.  Sectors
  M1.2    0542UT  possible   lower  E. Asia/Aust.
  M1.2    1644UT  possible   lower  South American/
                                    Atlantic
  M1.0    2234UT  possible   lower  East Pacific/
                                    North American

MUFs:
   Cocos Island Region:
      No data available during local day.
      No data available during local night.
   Niue Island Region:
      Mostly near predicted monthly values.
      Depressed by 20% after local dawn.
   Northern Australian Region:
      Mostly near predicted monthly values.
   Southern Australian Region:
      Mostly near predicted monthly values.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

PCA Event : No event.

Monthly T index:
Month  T index
Oct      130
Nov      100
Dec      98


2. FORECAST (19 NOVEMBER - 21 NOVEMBER)
Date   T index  Conditions       MUFs                              
19 Nov   100    Normal-fair      Near predicted monthly values 
                                 to 10-20% depressed
20 Nov    90    Fair             Near predicted monthly values 
                                 to 10-20% depressed    
21 Nov    95    Normal-fair      Near predicted monthly values 
                                 to 10-20% depressed   

COMMENT: ASWFC SWF HF Communications Warning 114 was issued on 
18 November and is current for 19-20 Nov. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 18-Nov were near predicted 
monthly values. Sporadic E was present during local dawn and 
night hours at most sites, especially in Brisbane, Hobart and 
Perth. HF conditions were generally degraded during these times. 

MUFs are expected to be near predicted monthly values on the 
first half of UT day 19-Nov, but tending to 10-20% depressed 
by the end of the day due to anticipated geomagnetic activity 
from a recent CME. MUFs may be 10-20% depressed over 20-21 Nov 
due to the CME induced geomagnetic activity followed by possible 
coronal hole geomagnetic activity. Sporadic E is expected to 
persist during local night hours. Isolated shortwave fadeouts 
are possible.

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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