SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 25 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 29-35 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 16.5 14.3 8.3 ASSSXM MMBBFF%%%. .. 10.0 9.4 4.9 00 01 17.3 15.9 9.0 SSSXX MMBBBFF%%% ... 10.2 10.5 5.3 01 02 17.6 17.0 9.5 ASSSX XMBBBBB%%% .... 10.4 11.2 5.6 02 03 17.7 17.5 9.8 ASSSX XMBBBBB%%% .... 10.7 11.6 5.7 03 04 17.9 17.8 9.9 ASSSX XMMBBBB%%% .... 10.9 11.8 5.8 04 05 17.7 17.6 9.8 ASSSX XMMBBBB%%% .... 11.0 11.7 5.7 05 06 16.4 17.0 9.6 ASSSX XMBBBBP%%. ... 10.3 11.4 5.6 06 07 15.6 16.1 9.1 SSSSX MMBBBP%%%. ... 9.7 10.8 5.3 07 08 15.3 14.5 8.4 ASSSXM MMBBF%%%%. .. 9.6 9.7 4.9 08 09 15.2 12.1 7.2 SSSMMM MMFFF%%%%. .. 9.4 8.0 4.2 09 10 13.2 5.5 3.7 AMMMMMMM MFF%%%%%.. ... 8.7 0.0 2.7 10 11 10.6 2.3 0.0 XMMMMMMMMM %%%%%..... .. 7.4 1.5 0.0 11 12 9.4 2.3 0.0 XMMMMMMMM% %%%%..... 6.6 1.5 0.0 12 13 8.8 2.3 0.0 XMMMMMMM%% %%%..... 6.2 1.5 0.0 13 14 8.8 2.3 0.0 XMMMMMMM%% %%..... 6.0 1.5 0.0 14 15 9.0 2.3 0.0 XMMMMMMF%% %%.... 6.0 1.5 0.0 15 16 8.5 2.3 0.0 XMMMMMMF%% %.... 5.8 1.5 0.0 16 17 8.0 2.3 0.0 XMMMMMM%%% %.... 5.6 1.5 0.0 17 18 7.1 2.3 0.0 XMMMMMF%%. ... 5.3 1.5 0.0 18 19 6.4 2.3 0.0 XMMMMM%%%. .. 4.7 1.5 0.0 19 20 6.0 2.3 0.0 XMMMMM%%.. . 4.4 1.5 0.0 20 21 6.1 2.3 0.0 XMMMMM%%.. . 4.6 1.5 0.0 21 22 9.1 2.3 0.0 MMMMMMMFF% %... 6.1 0.0 2.1 22 23 14.2 11.7 7.0 SSXMMM BFFF%%%.. 8.7 7.5 4.2 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) 25-Sep-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000