[Ips-hf-warning] ASWFC HF DEPRESSION WARNING issued 0813 UT on 28 May 2025 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC HF RADIO COMMUNICATIONS WARNING 25/54
ISSUED AT 0813UT/28 MAY 2025
BY THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE.

Coronal hole high speed wind stream impacts are producing HF 
depressions of up to 20% during local night in the Australian 
region, this is expected to continue over 28-30.

DEGRADED HF PROPAGATION CONDITIONS EXPECTED
FROM 28-30 MAY 2025
IF COMMS DIFFICULTIES EXPERIENCED TRY A LOWER FREQUENCY BAND
_____________________________________________________________

HF COMMUNICATIONS FORECAST (AUSTRALIAN/NEW ZEALAND REGION)
                                   FREQUENCY BANDS
       T-index      MUFs        2  4  6  8 12 16 22 26
_____________________________________________________________
28 May:   75          -15%      2  4  6  8 12 12 16 22
29 May:   75          -15%      2  4  6  8 12 12 16 22
30 May:   75          -15%      2  4  6  8 12 12 16 22

Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au