SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 11 April, 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 12-15 1E 2 1 5 10 15 20 25 30 35 40 2F 28-33 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 17.2 13.7 7.9 ASSXMM MMMFFFF%%% ... 10.9 8.8 4.7 00 01 18.7 15.4 8.8 SSSXX MMMMBFFF%% %%... 11.7 10.1 5.2 01 02 20.1 16.5 9.3 ASSSX MMMMBBFFFF %%%.... 12.1 10.9 5.5 02 03 20.5 17.1 9.6 ASSSX XMMMBBBFFF %%%.... 12.3 11.3 5.6 03 04 20.7 17.4 9.7 ASSSX XMMMBBBFFF %%%%.... 12.4 11.5 5.7 04 05 20.4 17.2 9.6 ASSSX XMMMMBBFFF %%%.... 12.5 11.4 5.6 05 06 19.3 16.6 9.3 SSSSX XMMMBBFFF% %%%.... 12.0 11.1 5.4 06 07 19.0 15.6 8.8 SSSXX MMMMBFFF%% %%%..... 11.7 10.4 5.1 07 08 18.3 13.9 8.0 ASSXXM MMMMFFFF%% %%..... 11.2 9.3 4.6 08 09 17.8 11.0 6.6 ASSXMMM MMMMFFF%%% %%.... 11.0 7.3 3.9 09 10 14.4 2.3 0.0 XMMMMMMMMM MMFF%%%%%. ..... 9.4 1.5 0.0 10 11 10.5 2.3 0.0 XMMMMMMMMM %%%%%..... .. 7.4 1.5 0.0 11 12 9.3 2.3 0.0 XMMMMMMMM% %%%...... 6.5 1.5 0.0 12 13 8.1 2.3 0.0 XMMMMMMM%% %%..... 5.8 1.5 0.0 13 14 8.0 2.3 0.0 XMMMMMM%%% %.... 5.7 1.5 0.0 14 15 8.2 2.3 0.0 XMMMMMMF%% %.... 5.7 1.5 0.0 15 16 8.2 2.3 0.0 XMMMMMMF%% %.... 5.6 1.5 0.0 16 17 7.9 2.3 0.0 XMMMMMM%%% .... 5.5 1.5 0.0 17 18 7.6 2.3 0.0 XMMMMMM%%% .... 5.4 1.5 0.0 18 19 7.1 2.3 0.0 XMMMMMF%%% ... 4.9 1.5 0.0 19 20 6.4 2.3 0.0 XMMMMM%%%. .. 4.5 1.5 0.0 20 21 5.7 2.3 0.0 XMMMM%%%.. . 4.0 1.5 0.0 21 22 7.4 2.3 0.0 XMMMMMF%%. .. 5.3 1.5 0.0 22 23 14.1 10.5 6.4 ASSMMMM FFFF%%... 8.6 6.5 3.9 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) 11-Apr-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000