SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 31 August, 2026 T-index: 90 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 17.9 13.9 8.2 ASSSMM MMBFFFF%%% .... 11.0 9.0 4.9 00 01 19.4 15.7 9.1 SSSSX MMMBBFFFF% %%.... 11.8 10.3 5.4 01 02 19.4 16.9 9.6 ASSSX XMMBBBFFF% %%.... 11.9 11.1 5.6 02 03 19.5 17.5 9.9 ASSSX XMMMBBBFF% %%.... 11.9 11.6 5.8 03 04 19.0 17.7 10.0 ASSSX XMMMBBBF%% %.... 11.9 11.8 5.9 04 05 18.6 17.6 9.9 ASSSX XMMBBBBF%% %.... 11.8 11.7 5.8 05 06 17.5 17.0 9.6 ASSSX XMMBBBB%%% .... 11.4 11.3 5.6 06 07 17.0 15.9 9.1 SSSSX MMMBBF%%%% .... 11.0 10.6 5.3 07 08 16.9 14.2 8.3 ASSSXM MMMBFF%%%% .... 10.9 9.5 4.8 08 09 16.8 11.2 6.8 ASSXMMM MMFFFF%%%% .... 10.7 7.4 4.0 09 10 14.6 2.4 0.0 XMMMMMMMMM MFFF%%%%.. ... 9.6 1.6 0.0 10 11 11.5 2.4 0.0 XMMMMMMMMM F%%%%..... . 7.9 1.6 0.0 11 12 10.1 2.4 0.0 XMMMMMMMFF %%%..... 7.0 1.6 0.0 12 13 9.3 2.4 0.0 XMMMMMMMF% %%..... 6.4 1.6 0.0 13 14 8.9 2.4 0.0 XMMMMMMF%% %%.... 6.1 1.6 0.0 14 15 8.6 2.4 0.0 XMMMMMMF%% %.... 5.8 1.6 0.0 15 16 8.2 2.4 0.0 XMMMMMMF%% %.... 5.7 1.6 0.0 16 17 7.8 2.4 0.0 XMMMMMF%%% .... 5.5 1.6 0.0 17 18 7.1 2.4 0.0 XMMMMMF%%. ... 5.3 1.6 0.0 18 19 6.6 2.4 0.0 XMMMMM%%%. ... 4.8 1.6 0.0 19 20 6.0 2.4 0.0 XMMMM%%%.. . 4.3 1.6 0.0 20 21 5.7 2.4 0.0 XMMMM%%%.. . 4.3 1.6 0.0 21 22 7.6 2.4 0.0 XMMMMMF%%. .. 5.4 1.6 0.0 22 23 14.4 10.7 6.6 ASSMMMM FFFF%%... 8.9 6.6 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) 31-Aug-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000