SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 23 September, 2026 T-index: 50 Bearings: 201 24 Distance: 1680 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 12-16 1E 2 1 5 10 15 20 25 30 35 40 2F 28-34 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 15.2 13.9 8.0 ASSXXM MBBFF%%%.. . 9.3 9.1 4.7 00 01 16.0 15.5 8.7 SSSXX MBBBB%%%%. .. 9.6 10.2 5.1 01 02 16.2 16.5 9.2 SSSSX MBBBBB%%%. .. 9.5 10.9 5.4 02 03 16.2 17.1 9.4 ASSSX XMBBBBP%%. .. 9.7 11.3 5.5 03 04 16.3 17.3 9.5 ASSSX XMBBBBP%%. .. 10.0 11.5 5.6 04 05 16.1 17.1 9.5 ASSSX XMBBBBP%%. .. 10.0 11.4 5.5 05 06 15.3 16.6 9.2 SSSSX XBBBBP%%.. . 9.6 11.1 5.3 06 07 14.7 15.6 8.8 SSSXX MBBBP%%%.. . 9.3 10.5 5.1 07 08 14.4 14.1 8.1 ASSSXM MBBB%%%... . 9.1 9.5 4.7 08 09 14.1 11.7 6.9 ASSXMMM MFFF%%%... 8.9 7.7 4.0 09 10 12.0 4.8 3.3 AMMMMMMM F%%%%%.... . 8.1 0.0 2.5 10 11 9.6 2.1 0.0 XMMMMMMMM% %%%%..... 6.7 1.4 0.0 11 12 8.5 2.1 0.0 XMMMMMMM%% %%..... 6.1 1.4 0.0 12 13 7.9 2.1 0.0 XMMMMMM%%% %..... 5.7 1.4 0.0 13 14 7.7 2.1 0.0 XMMMMMM%%% %.... 5.5 1.4 0.0 14 15 8.1 2.1 0.0 XMMMMMMF%% .... 5.5 1.4 0.0 15 16 7.8 2.1 0.0 XMMMMMF%%% .... 5.3 1.4 0.0 16 17 7.4 2.1 0.0 XMMMMMF%%% ... 5.2 1.4 0.0 17 18 6.6 2.1 0.0 XMMMMM%%%. .. 4.9 1.4 0.0 18 19 6.0 2.1 0.0 XMMMM%%%.. . 4.4 1.4 0.0 19 20 5.5 2.1 0.0 XMMMM%%... 4.0 1.4 0.0 20 21 5.6 2.1 0.0 XMMMM%%... 4.3 1.4 0.0 21 22 8.4 2.1 0.0 MMMMMMMF%% ... 5.7 0.0 1.9 22 23 13.0 11.3 6.7 ASSXMMB BF%%%... 8.1 7.3 4.0 23 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT =============================================================================== |. USABLE LESS THAN 50% OF DAYS |% USABLE 50% TO 90% OF DAYS | |B BOTH E and F MODES 90% OF DAYS |M MIXED FIRST AND SECOND F MODES | |F FIRST F MODE ONLY |E E-LAYER PROPAGATION |P 90% E and 50-90% F | |S SECOND MODES ONLY |A HIGH ABSORPTION |X COMPLEX MODES | (c) 23-Sep-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000