SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 5 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 28-34 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 16.4 13.8 8.0 ASSXMM MMBFFF%%%. .. 10.5 8.9 4.7 00 01 17.9 15.5 8.8 SSSXX MMMBBFF%%% %... 11.2 10.2 5.2 01 02 19.2 16.6 9.3 SSSSX MMMMBBFFF% %%.... 11.6 10.9 5.4 02 03 19.7 17.2 9.6 ASSSX XMMMBBBFF% %%.... 11.7 11.4 5.6 03 04 19.8 17.4 9.7 ASSSX XMMMBBBFF% %%%... 11.8 11.5 5.6 04 05 19.7 17.2 9.6 ASSSX XMMMBBBFF% %%%... 11.9 11.4 5.6 05 06 18.7 16.6 9.3 SSSSX XMMMBBFF%% %%.... 11.5 11.1 5.4 06 07 18.4 15.6 8.8 SSSXX MMMMBFFF%% %%..... 11.3 10.4 5.1 07 08 17.8 14.0 8.1 ASSSXM MMMBFFF%%% %%.... 11.0 9.4 4.7 08 09 17.3 11.2 6.7 ASSXMMM MMMFFFF%%% %.... 10.8 7.4 3.9 09 10 14.1 2.2 0.0 XMMMMMMMMM MMFF%%%%%. .... 9.1 1.5 0.0 10 11 10.4 2.2 0.0 XMMMMMMMMM %%%%%..... . 7.3 1.5 0.0 11 12 9.0 2.2 0.0 XMMMMMMM%% %%%..... 6.4 1.5 0.0 12 13 8.0 2.2 0.0 XMMMMMM%%% %%.... 5.8 1.5 0.0 13 14 7.9 2.2 0.0 XMMMMMM%%% %.... 5.6 1.5 0.0 14 15 8.1 2.2 0.0 XMMMMMMF%% %.... 5.7 1.5 0.0 15 16 8.1 2.2 0.0 XMMMMMMF%% %.... 5.6 1.5 0.0 16 17 7.9 2.2 0.0 XMMMMMM%%% .... 5.5 1.5 0.0 17 18 7.6 2.2 0.0 XMMMMMM%%% .... 5.4 1.5 0.0 18 19 7.1 2.2 0.0 XMMMMMF%%% ... 5.0 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%%%.. 4.1 1.5 0.0 21 22 7.5 2.2 0.0 XMMMMMF%%. .. 5.3 1.5 0.0 22 23 13.7 10.8 6.5 ASSMMMM FFF%%%... 8.5 6.8 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) 5-Apr-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000