SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 27 February, 2026 T-index: 100 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 15.5 15.3 9.0 SSSXM MBBBB%%%.. . 9.5 10.0 5.3 00 01 16.7 16.8 9.7 ASSSX XMBBBB%%%% ... 10.1 11.1 5.7 01 02 17.3 17.8 10.2 ASSSS XMBBBBB%%% ... 10.4 11.8 5.9 02 03 18.1 18.4 10.5 SSSS XXMBBBBB%% %... 10.9 12.2 6.1 03 04 18.3 18.6 10.6 SSSS XXMBBBBB%% %.... 11.1 12.4 6.1 04 05 18.6 18.4 10.5 SSSS XXMBBBBB%% %.... 11.2 12.3 6.1 05 06 18.5 17.9 10.2 ASSSS XMMBBBBF%% %%.... 11.2 11.9 5.9 06 07 17.9 16.9 9.8 ASSSX XMMBBBF%%% %..... 10.9 11.4 5.7 07 08 17.4 15.4 9.0 SSSXX MMMBBFF%%% %.... 10.7 10.3 5.3 08 09 16.7 13.1 7.9 ASSXMM MMMFFF%%%% .... 10.4 8.6 4.7 09 10 15.3 8.5 5.5 ASMMMMM MMFFF%%%%. .... 9.8 4.8 3.5 10 11 13.8 2.5 0.0 XMMMMMMMMM MFF%%%%%.. ... 9.2 1.6 0.0 11 12 12.3 2.5 0.0 XMMMMMMMMM FF%%%%.... 8.3 1.6 0.0 12 13 11.6 2.5 0.0 XMMMMMMMMF F%%%%.... 7.8 1.6 0.0 13 14 10.6 2.5 0.0 XMMMMMMMMF %%%.... 7.1 1.6 0.0 14 15 10.6 2.5 0.0 XMMMMMMMFF %%%.... 7.0 1.6 0.0 15 16 10.6 2.5 0.0 XMMMMMMMFF %%%.... 6.9 1.6 0.0 16 17 10.4 2.5 0.0 XMMMMMMMFF %%%.... 6.7 1.6 0.0 17 18 9.2 2.5 0.0 XMMMMMMMF% %%.... 6.4 1.6 0.0 18 19 8.4 2.5 0.0 XMMMMMMF%% %.... 6.0 1.6 0.0 19 20 7.3 2.5 0.0 XMMMMMF%%% ... 5.4 1.6 0.0 20 21 6.9 2.5 0.0 XMMMMM%%%. .. 5.2 1.6 0.0 21 22 9.4 7.5 5.0 SMMMFF% %%... 6.3 4.4 3.1 22 23 13.9 12.8 7.8 ASSXMM BBF%%%... 8.3 8.4 4.6 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) 27-Feb-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000