SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 29 March, 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 28-35 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 17.8 14.4 8.4 ASSSXM MMMBFFF%%% ... 11.3 9.4 5.0 00 01 19.6 16.1 9.3 SSSSX MMMMBBFFF% %%... 12.1 10.6 5.4 01 02 20.6 17.2 9.8 ASSSX XMMMBBBFFF %%%.... 12.4 11.3 5.7 02 03 21.1 17.8 10.1 ASSSS XMMMBBBFFF F%%.... 12.5 11.8 5.9 03 04 21.3 18.0 10.2 ASSSS XMMMMBBBFF F%%%... 12.6 11.9 5.9 04 05 21.3 17.8 10.1 ASSSS XMMMMBBFFF F%%.... 12.7 11.9 5.9 05 06 20.5 17.3 9.8 ASSSX XMMMMBBFFF %%%.... 12.4 11.5 5.7 06 07 19.9 16.2 9.3 SSSSX MMMMBBFFF% %%%..... 12.1 10.9 5.4 07 08 19.5 14.6 8.5 ASSSXM MMMMFFFFF% %%%.... 11.8 9.8 5.0 08 09 19.1 11.9 7.2 SSSMMM MMMMFFFFF% %%.... 11.6 7.9 4.2 09 10 16.3 2.4 0.0 MMMMMMMMMM MMMFFF%%%% ...... 10.2 0.0 1.9 10 11 12.9 2.4 0.0 XMMMMMMMMM MF%%%%%... ... 8.7 1.6 0.0 11 12 11.2 2.4 0.0 XMMMMMMMMM F%%%%..... 7.7 1.6 0.0 12 13 10.1 2.4 0.0 XMMMMMMMMF %%%..... 6.9 1.6 0.0 13 14 9.5 2.4 0.0 XMMMMMMMF% %%..... 6.6 1.6 0.0 14 15 9.5 2.4 0.0 XMMMMMMMF% %%..... 6.4 1.6 0.0 15 16 9.3 2.4 0.0 XMMMMMMMF% %%.... 6.3 1.6 0.0 16 17 9.2 2.4 0.0 XMMMMMMFF% %%.... 6.1 1.6 0.0 17 18 8.5 2.4 0.0 XMMMMMMF%% %.... 6.0 1.6 0.0 18 19 7.9 2.4 0.0 XMMMMMM%%% %... 5.6 1.6 0.0 19 20 6.9 2.4 0.0 XMMMMM%%%. ... 5.0 1.6 0.0 20 21 6.4 2.4 0.0 XMMMMM%%.. .. 4.6 1.6 0.0 21 22 8.7 2.4 0.0 XMMMMMMF%% %.. 5.9 1.6 0.0 22 23 15.2 11.5 7.0 SSXMMM BFFFF%%... 9.2 7.3 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) 29-Mar-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000