SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 8 April, 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 18.6 14.1 8.3 ASSSXM MMMMFFFF%% %... 11.8 9.1 4.9 00 01 20.3 15.9 9.1 SSSSX MMMMMFFFFF %%%... 12.6 10.4 5.4 01 02 21.7 17.0 9.7 ASSSX XMMMMBBFFF F%%%%... 13.0 11.2 5.7 02 03 22.2 17.6 10.0 ASSSX XMMMMBBFFF FF%%%... 13.0 11.6 5.8 03 04 22.4 17.8 10.1 ASSSS XMMMMBBFFF FF%%%.... 13.1 11.8 5.9 04 05 22.1 17.6 10.0 ASSSX XMMMMBBFFF FF%%.... 13.3 11.7 5.8 05 06 21.0 17.1 9.7 ASSSX XMMMMBBFFF %%%%.... 12.9 11.4 5.6 06 07 20.6 16.0 9.2 SSSSX MMMMMBFFFF %%%%.... 12.6 10.7 5.3 07 08 19.9 14.3 8.4 ASSSXM MMMMMFFFF% %%%.... 12.2 9.6 4.8 08 09 19.5 11.4 6.9 SSXMMM MMMMFFFFF% %%%.... 12.0 7.5 4.1 09 10 16.4 2.4 0.0 XMMMMMMMMM MMMFFF%%%% %..... 10.4 1.6 0.0 10 11 12.6 2.4 0.0 XMMMMMMMMM MF%%%%%... ... 8.6 1.6 0.0 11 12 11.2 2.4 0.0 XMMMMMMMMM F%%%%..... 7.7 1.6 0.0 12 13 9.8 2.4 0.0 XMMMMMMMF% %%%..... 6.8 1.6 0.0 13 14 9.3 2.4 0.0 XMMMMMMMF% %%..... 6.5 1.6 0.0 14 15 9.3 2.4 0.0 XMMMMMMMF% %%.... 6.3 1.6 0.0 15 16 9.2 2.4 0.0 XMMMMMMFF% %%.... 6.1 1.6 0.0 16 17 8.9 2.4 0.0 XMMMMMMF%% %.... 6.0 1.6 0.0 17 18 8.4 2.4 0.0 XMMMMMMF%% %.... 5.9 1.6 0.0 18 19 7.7 2.4 0.0 XMMMMMM%%% .... 5.4 1.6 0.0 19 20 6.9 2.4 0.0 XMMMMM%%%. ... 4.9 1.6 0.0 20 21 6.3 2.4 0.0 XMMMMM%%.. . 4.5 1.6 0.0 21 22 8.3 2.4 0.0 XMMMMMMF%% ... 5.8 1.6 0.0 22 23 15.4 11.0 6.7 SSMMMM MFFFF%%%.. 9.3 6.8 4.1 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) 8-Apr-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000