SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 10 April, 2026 T-index: 65 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 16.8 13.6 7.9 ASSXMM MMMFFF%%%% ... 10.7 8.8 4.7 00 01 18.3 15.4 8.7 SSSXX MMMBBFFF%% %.... 11.4 10.1 5.1 01 02 19.7 16.4 9.2 SSSSX MMMMBBFFF% %%%... 11.8 10.8 5.4 02 03 20.1 17.1 9.5 ASSSX XMMMBBBFFF %%%.... 12.0 11.3 5.6 03 04 20.2 17.3 9.6 ASSSX XMMMBBBFFF %%%.... 12.0 11.5 5.6 04 05 20.0 17.1 9.5 ASSSX XMMMBBBFF% %%%.... 12.2 11.4 5.6 05 06 19.0 16.5 9.3 SSSSX MMMMBBFF%% %%%.... 11.7 11.0 5.4 06 07 18.7 15.5 8.8 SSSXX MMMMBFFF%% %%%.... 11.6 10.4 5.1 07 08 18.0 13.8 8.0 ASSXXM MMMMFFF%%% %%.... 11.2 9.3 4.6 08 09 17.5 11.0 6.6 ASSXMMM MMMFFFF%%% %.... 10.9 7.3 3.8 09 10 14.1 2.2 0.0 XMMMMMMMMM MMFF%%%%%. .... 9.2 1.5 0.0 10 11 10.2 2.2 0.0 XMMMMMMMMM %%%%%..... . 7.2 1.5 0.0 11 12 9.0 2.2 0.0 XMMMMMMM%% %%%..... 6.3 1.5 0.0 12 13 7.9 2.2 0.0 XMMMMMM%%% %..... 5.6 1.5 0.0 13 14 7.8 2.2 0.0 XMMMMMM%%% %.... 5.5 1.5 0.0 14 15 8.0 2.2 0.0 XMMMMMM%%% .... 5.6 1.5 0.0 15 16 8.0 2.2 0.0 XMMMMMM%%% .... 5.5 1.5 0.0 16 17 7.7 2.2 0.0 XMMMMMM%%% .... 5.5 1.5 0.0 17 18 7.5 2.2 0.0 XMMMMMM%%% .... 5.4 1.5 0.0 18 19 7.0 2.2 0.0 XMMMMM%%%. ... 4.9 1.5 0.0 19 20 6.3 2.2 0.0 XMMMMM%%.. .. 4.5 1.5 0.0 20 21 5.6 2.2 0.0 XMMMM%%%.. 4.0 1.5 0.0 21 22 7.3 2.2 0.0 XMMMMMF%%. .. 5.2 1.5 0.0 22 23 13.8 10.5 6.4 ASSMMMM FFF%%%... 8.5 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) 10-Apr-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000