SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 21 October, 2026 T-index: 55 Bearings: 201 24 Distance: 1680 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 12-18 1E 2 1 5 10 15 20 25 30 35 40 2F 29-37 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 14.2 14.6 8.3 ASSSXM BBBB%%%... 8.7 9.6 4.9 00 01 14.4 16.0 9.0 SSSXX BBBBPP%... 8.8 10.6 5.3 01 02 15.0 17.0 9.4 ASSSX XBBBPPP%.. . 9.2 11.2 5.5 02 03 15.9 17.5 9.7 ASSSX XBBBBPP%%. .. 9.6 11.6 5.6 03 04 16.5 17.7 9.8 ASSSX XMBBBBP%%. ... 9.9 11.8 5.7 04 05 16.6 17.5 9.7 ASSSX XMBBBBP%%. ... 10.1 11.7 5.6 05 06 15.7 17.0 9.5 ASSSX XMBBBPP%%. .. 9.9 11.4 5.5 06 07 15.0 16.2 9.1 SSSSX MBBBPP%%.. .. 9.3 10.8 5.3 07 08 14.4 14.8 8.4 ASSSXM MBBB%%%... . 9.1 9.9 4.9 08 09 14.6 12.7 7.4 SSSXMM MBFF%%%%.. . 9.1 8.3 4.4 09 10 12.8 8.6 5.4 SSMMMMM MF%%%%%... .. 8.6 5.0 3.4 10 11 11.1 2.2 0.0 XMMMMMMMMM F%%%%%.... .. 7.7 1.4 0.0 11 12 9.7 2.2 0.0 XMMMMMMMM% %%%%..... 6.9 1.4 0.0 12 13 9.0 2.2 0.0 XMMMMMMM%% %%%..... 6.2 1.4 0.0 13 14 9.0 2.2 0.0 XMMMMMMM%% %%..... 6.0 1.4 0.0 14 15 9.2 2.2 0.0 XMMMMMMFF% %%.... 6.1 1.4 0.0 15 16 8.9 2.2 0.0 XMMMMMMF%% %%.... 5.9 1.4 0.0 16 17 8.4 2.2 0.0 XMMMMMMF%% %.... 5.7 1.4 0.0 17 18 7.3 2.2 0.0 XMMMMMF%%% ... 5.4 1.4 0.0 18 19 6.6 2.2 0.0 XMMMMM%%%. .. 4.9 1.4 0.0 19 20 6.2 2.2 0.0 XMMMMM%%.. . 4.8 1.4 0.0 20 21 6.8 2.2 0.0 XMMMMM%%%. ... 5.1 1.4 0.0 21 22 10.2 7.8 5.0 ASMMMMFF %%%... 6.8 4.9 3.0 22 23 13.3 12.4 7.3 SSSXMM BBF%%%... 8.2 8.1 4.3 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) 21-Oct-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000