Ionospheric Summary and Forecast

Ionospheric Summary

(last updated 01 May 2026 23:30 UT)

Date T index 01 May 84 Observed Australian Regional MUFs Cocos Island Region: No data available during local day. No data available during local night. Niue Island Region: Enhanced by 15% during local day. Near predicted monthly values during local night. Northern Australian Region: Near predicted monthly values. Southern Australian Region: Near predicted monthly values. Antarctic Region (Casey/Davis/Mawson): Depressed by 20% over the UT day. Monthly T index: Month T index Apr 74 May 71 Jun 68

Ionospheric Forecast

(last updated 01 May 2026 23:30 UT)

Date T index MUFs 02 May 85 Near predicted monthly values 03 May 85 Near predicted monthly values 04 May 85 Near predicted monthly values COMMENT: ASWFC SWF HF Communications Warning 45 was issued on 1 May and is current for 1-2 May. Maximum Usable Frequencies (MUFs) in the Australian region on 01-May were mostly near predicted monthly values, with some enhancements seen at Niue Island. Spread-F and sporadic-E were observed at Perth and Hobart, with sporadic-E also observed at Canberra. Depressions of 20% were observed in the Antarctic region. MUFs are expected to be near predicted monthly values over 02-04 May. Isolated shortwave fadeouts are possible.