SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 13 September, 2026 T-index: 70 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 16.8 14.0 8.1 ASSSXM MMBBFF%%%% ... 10.3 9.1 4.8 00 01 17.8 15.7 8.9 SSSXX MMMBBFF%%% %... 10.7 10.3 5.2 01 02 18.0 16.8 9.4 ASSSX XMMBBBF%%% %... 10.7 11.1 5.5 02 03 18.0 17.4 9.7 ASSSX XMMBBBB%%% %... 10.9 11.5 5.7 03 04 17.9 17.6 9.8 ASSSX XMMBBBB%%% .... 11.0 11.7 5.7 04 05 17.6 17.4 9.7 ASSSX XMMBBBB%%% ... 11.0 11.6 5.7 05 06 16.3 16.8 9.5 ASSSX XMBBBB%%%. ... 10.4 11.2 5.5 06 07 15.6 15.8 9.0 SSSXX MMBBB%%%%. ... 9.9 10.6 5.2 07 08 15.5 14.2 8.2 ASSSXM MMBBF%%%%. ... 9.8 9.6 4.8 08 09 15.1 11.6 6.9 SSXMMM MMFFF%%%.. .. 9.6 7.6 4.1 09 10 13.0 2.3 0.0 MMMMMMMMMM MF%%%%%... .. 8.7 0.0 1.5 10 11 10.2 2.3 0.0 XMMMMMMMMF %%%%%..... . 7.1 1.5 0.0 11 12 9.1 2.3 0.0 XMMMMMMMF% %%%..... 6.4 1.5 0.0 12 13 8.4 2.3 0.0 XMMMMMMM%% %%..... 6.0 1.5 0.0 13 14 8.2 2.3 0.0 XMMMMMMF%% %..... 5.8 1.5 0.0 14 15 8.5 2.3 0.0 XMMMMMMF%% %.... 5.7 1.5 0.0 15 16 8.1 2.3 0.0 XMMMMMMF%% %.... 5.5 1.5 0.0 16 17 7.6 2.3 0.0 XMMMMMF%%% .... 5.4 1.5 0.0 17 18 6.9 2.3 0.0 XMMMMM%%%. ... 5.1 1.5 0.0 18 19 6.3 2.3 0.0 XMMMMM%%.. .. 4.6 1.5 0.0 19 20 5.7 2.3 0.0 XMMMM%%%.. . 4.1 1.5 0.0 20 21 5.6 2.3 0.0 XMMMM%%%.. 4.2 1.5 0.0 21 22 8.1 2.3 0.0 XMMMMMMF%% ... 5.5 1.5 0.0 22 23 13.7 11.2 6.7 ASSXMMM BFF%%%... 8.5 7.1 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) 13-Sep-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000