Ionospheric Summary and Forecast

Ionospheric Summary

(last updated 30 Jun 2025 23:30 UT)

Date T index 30 Jun 83 Observed Australian Regional MUFs Cocos Island Region: Enhanced by 40% during local day. Depressed by 25% during local night. Niue Island Region: Depressed by 25% during local day. Enhanced by 25% during local night. Northern Australian Region: Near predicted monthly values during local day. Depressed by 15% during local night. Southern Australian Region: Near predicted monthly values during local day. Depressed by 15% during local night. Antarctic Region (Casey/Davis/Mawson): Depressed by 15% over the UT day. Monthly T index: Month T index May 94 Jun 109 Jul 107

Ionospheric Forecast

(last updated 30 Jun 2025 23:30 UT)

Date T index MUFs 01 Jul 85 Near predicted values 02 Jul 80 Near predicted values to 15% depressed 03 Jul 75 Near predicted monthly values to 15% depressed COMMENT: Maximum usable frequencies (MUFs) on UT day 30-Jun in the Australian region were near predicted values to 15% depressed. Signal spreading was observed in Niue and Hobart during local night hours. Sporadic-E was observed in Hobart and Learmonth. MUFs are expected to be near predicted values on UT day 1-Jul, then becoming 15% depressed over 2-3 Jul due to geomagnetic activity.