SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 23 August, 2026 T-index: 80 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 16.6 13.5 7.9 ASSXMM MMBFFF%%%. ... 10.4 8.7 4.7 00 01 18.2 15.4 8.8 SSSXX MMMBBFFF%% %.... 11.3 10.1 5.2 01 02 18.4 16.5 9.3 ASSSX MMMBBBFF%% %.... 11.5 10.9 5.5 02 03 18.4 17.2 9.7 ASSSX XMMBBBBF%% %..... 11.5 11.3 5.7 03 04 17.8 17.4 9.8 ASSSX XMMBBBB%%% %.... 11.4 11.5 5.7 04 05 17.4 17.2 9.7 ASSSX XMMBBBB%%% .... 11.3 11.4 5.7 05 06 16.5 16.6 9.4 ASSSX XMBBBB%%%% .... 10.7 11.1 5.5 06 07 15.9 15.5 8.9 SSSXX MMBBB%%%%. .... 10.5 10.4 5.2 07 08 15.7 13.8 8.0 ASSXXM MMBFF%%%%. .... 10.3 9.2 4.7 08 09 15.7 10.6 6.5 ASSXMMM MMFFF%%%%. .... 10.4 7.1 3.8 09 10 13.3 2.3 0.0 XMMMMMMMMM MFF%%%%... ... 8.9 1.5 0.0 10 11 10.4 2.3 0.0 XMMMMMMMMF %%%%...... 7.2 1.5 0.0 11 12 9.1 2.3 0.0 XMMMMMMMF% %%..... 6.3 1.5 0.0 12 13 8.3 2.3 0.0 XMMMMMMF%% %..... 5.8 1.5 0.0 13 14 8.0 2.3 0.0 XMMMMMM%%% ..... 5.6 1.5 0.0 14 15 7.7 2.3 0.0 XMMMMMF%%% .... 5.3 1.5 0.0 15 16 7.4 2.3 0.0 XMMMMMF%%% ... 5.2 1.5 0.0 16 17 7.1 2.3 0.0 XMMMMMF%%. ... 5.1 1.5 0.0 17 18 6.6 2.3 0.0 XMMMMM%%%. ... 4.9 1.5 0.0 18 19 6.3 2.3 0.0 XMMMMM%%%. .. 4.6 1.5 0.0 19 20 5.6 2.3 0.0 XMMMM%%%.. . 4.1 1.5 0.0 20 21 5.2 2.3 0.0 XMMMM%%... 4.0 1.5 0.0 21 22 6.6 2.3 0.0 XMMMMM%%.. . 4.8 1.5 0.0 22 23 13.3 10.1 6.2 ASSMMMB FFF%%... 8.3 6.1 3.8 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) 23-Aug-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000