Ionospheric Summary and Forecast

Ionospheric Summary

(last updated 18 Mar 2026 23:30 UT)

Date T index 18 Mar 87 Observed Australian Regional MUFs Cocos Island Region: Near predicted monthly values during local day. Depressed by 15% during local night. Niue Island Region: Near predicted monthly values during local day. Depressed by 20% during local night. Northern Australian Region: Near predicted monthly values. Southern Australian Region: Near predicted monthly values. Antarctic Region (Casey/Davis/Mawson): Near predicted monthly values over the UT day. Monthly T index: Month T index Feb 98 Mar 87 Apr 85

Ionospheric Forecast

(last updated 18 Mar 2026 23:30 UT)

Date T index MUFs 19 Mar 80 Near predicted monthly values, depressed 15% late in UT day. 20 Mar 60 Depressed by up to 20% 21 Mar 60 Depressed by up to 20% COMMENT: Maximum usable frequencies (MUFs) in the Australian region on UT day 18-Mar were near predicted monthly values. MUFs are expected to be near predicted monthly values for most of the UT day 19-Mar, then becoming 15% depressed late in the UT day (after local dawn 20-Mar). Australian regional MUFs are expected to be depressed by up to 20% over 20-21 Mar due to an anticipated increase in geomagnetic activity from two CME arrivals and coronal hole wind streams.