SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 4 May, 2026 T-index: 85 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 28-32 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 18.2 13.1 7.7 ASSXMM MMMFFFFF%% %.... 11.6 8.4 4.6 00 01 20.5 15.1 8.7 SSSXM MMMMMFFFFF %%%%.... 12.8 9.8 5.2 01 02 21.0 16.3 9.3 ASSSX MMMMMBFFFF %%%%..... 13.3 10.7 5.5 02 03 21.1 17.0 9.6 ASSSX XMMMMBBFFF F%%%..... 13.3 11.2 5.6 03 04 20.9 17.2 9.7 ASSSX XMMMMBBFFF %%%%..... 13.0 11.4 5.7 04 05 20.4 17.0 9.6 ASSSX XMMMMBBFFF %%%..... 12.9 11.3 5.6 05 06 19.8 16.4 9.3 SSSSX MMMMMBFFF% %%%..... 12.8 10.9 5.4 06 07 19.9 15.3 8.8 SSSXX MMMMMFFFF% %%%%..... 12.8 10.2 5.1 07 08 19.4 13.4 7.9 ASSXMM MMMMMFFFF% %%%..... 12.6 8.9 4.6 08 09 18.5 9.9 6.1 ASSMMMM MMMMFFFF%% %%..... 12.0 6.6 3.5 09 10 14.8 2.4 0.0 XMMMMMMMMM MMFF%%%%.. .... 9.8 1.6 0.0 10 11 11.5 2.4 0.0 XMMMMMMMMM F%%%%..... . 7.9 1.6 0.0 11 12 9.8 2.4 0.0 XMMMMMMMF% %%%..... 6.8 1.6 0.0 12 13 8.6 2.4 0.0 XMMMMMMF%% %..... 6.0 1.6 0.0 13 14 8.1 2.4 0.0 XMMMMMMF%% %.... 5.7 1.6 0.0 14 15 7.6 2.4 0.0 XMMMMMM%%% .... 5.6 1.6 0.0 15 16 7.7 2.4 0.0 XMMMMMF%%% .... 5.5 1.6 0.0 16 17 7.3 2.4 0.0 XMMMMMF%%% ... 5.4 1.6 0.0 17 18 7.0 2.4 0.0 XMMMMM%%%% ... 5.1 1.6 0.0 18 19 6.7 2.4 0.0 XMMMMM%%%. ... 4.7 1.6 0.0 19 20 6.2 2.4 0.0 XMMMMM%%%. .. 4.3 1.6 0.0 20 21 5.7 2.4 0.0 XMMMM%%%.. . 4.2 1.6 0.0 21 22 7.1 2.4 0.0 XMMMMMF%%. .. 5.1 1.6 0.0 22 23 14.4 9.3 5.8 ASMMMMM FFFF%%%... 8.8 5.2 3.7 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) 4-May-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000