Ionospheric Summary and Forecast
Ionospheric Summary
(last updated 21 Jul 2026 23:30 UT)
Date T index 21 Jul 76 Observed Australian Regional MUFs Cocos Island Region: No data available during local day. No data available during local night. Niue Island Region: Near predicted monthly values. Northern Australian Region: Near predicted monthly values. Southern Australian Region: Near predicted monthly values during local day. Enhanced by 25% during local night. Antarctic Region (Casey/Davis/Mawson): Near predicted monthly values over the UT day. Monthly T index: Month T index Jun 81 Jul 66 Aug 63
Ionospheric Forecast
(last updated 21 Jul 2026 23:30 UT)
Date T index MUFs 22 Jul 50 Depressed 15%/near predicted monthly values 23 Jul 50 Depressed 15%/near predicted monthly values 24 Jul 65 Near predicted monthly values COMMENT: ASWFC SWF HF Communications Warning 66 was issued on 21 July and is current for 21-22 Jul. Maximum Usable Frequencies (MUFs) in the Australian region were near predicted values on 21-Jul, with some enhancements of up to 25% observed in the southern Australian region during local night hours. Sporadic E was observed in the northern Australian region, Norfolk Island, and Niue Island during local night hours. MUFs are forecast to become depressed by up to 15% over 22-23 Jul due to expected geomagnetic activity over this period, before recovering to near predicted values on 24-Jul. Shortwave fadeouts are possible.
