Ionospheric Summary and Forecast

Ionospheric Summary

(last updated 27 Dec 2025 23:30 UT)

Date T index 27 Dec 124 Observed Australian Regional MUFs Cocos Island Region: No data. Niue Island Region: Near predicted monthly values. Northern Australian Region: Near predicted monthly values during local day. Enhanced by 30% during local night. Southern Australian Region: Near predicted monthly values during local day. Enhanced by 20% during local night. Antarctic Region (Casey/Davis/Mawson): Near predicted monthly values over the UT day. Monthly T index: Month T index Nov 103 Dec 89 Jan 89

Ionospheric Forecast

(last updated 27 Dec 2025 23:30 UT)

Date T index MUFs 28 Dec 115 Near predicted monthly values to 15% enhanced 29 Dec 115 Near predicted monthly values to 15% enhanced 30 Dec 115 Near predicted monthly values to 15% enhanced COMMENT: ASWFC SWF HF Communications Warning 124 was issued on 27 December and is current for 27-29 Dec. Maximum usable frequencies (MUFs) in the Australian region on UT day 27-Dec were near predicted values to 30% enhanced. Sporadic was observed at times at some sites. A shortwave fadeout was observed 27/0143-0226UT. MUFs are expected to be near predicted values to 15% enhanced over 28-30 Dec. HF conditions for the southern Australian region may become degraded during local night hours on 30-Dec, with mild depressions possible on 31-Dec. Isolated shortwave fadeouts are possible.