SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 28 August, 2026 T-index: 55 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 15.2 13.3 7.6 ASSXMM MBBFF%%%.. . 9.6 8.6 4.5 00 01 16.5 15.0 8.5 ASSSXM MMBBBF%%%. ... 10.2 9.8 5.0 01 02 16.4 16.1 9.0 SSSXX MMBBBB%%%. ... 10.2 10.6 5.3 02 03 16.2 16.8 9.3 SSSSX XMBBBB%%%. ... 10.3 11.1 5.4 03 04 15.7 17.0 9.4 ASSSX XMBBBPP%%. ... 10.3 11.2 5.5 04 05 15.4 16.8 9.3 SSSSX XMBBBP%%%. .. 10.2 11.2 5.4 05 06 14.8 16.2 9.0 SSSXX MMBBPP%%.. .. 9.8 10.8 5.3 06 07 14.5 15.2 8.5 ASSSXX MBBBP%%%.. .. 9.6 10.1 5.0 07 08 14.2 13.5 7.8 ASSXXM MBBF%%%... .. 9.4 9.1 4.5 08 09 14.0 10.6 6.3 ASSMMMM MFF%%%%... . 9.3 7.0 3.7 09 10 11.8 2.2 0.0 XMMMMMMMMM F%%%%..... 8.1 1.4 0.0 10 11 9.3 2.2 0.0 XMMMMMMMF% %%...... 6.6 1.4 0.0 11 12 8.2 2.2 0.0 XMMMMMMF%% %..... 5.8 1.4 0.0 12 13 7.5 2.2 0.0 XMMMMMM%%% .... 5.3 1.4 0.0 13 14 7.4 2.2 0.0 XMMMMMF%%% .... 5.2 1.4 0.0 14 15 7.3 2.2 0.0 XMMMMMF%%. ... 5.1 1.4 0.0 15 16 7.1 2.2 0.0 XMMMMMF%%. ... 5.0 1.4 0.0 16 17 6.8 2.2 0.0 XMMMMM%%%. .. 4.9 1.4 0.0 17 18 6.2 2.2 0.0 XMMMMM%%.. .. 4.7 1.4 0.0 18 19 5.7 2.2 0.0 XMMMM%%%.. .. 4.2 1.4 0.0 19 20 5.1 2.2 0.0 XMMMM%%... 3.7 1.4 0.0 20 21 4.9 2.2 0.0 XMMMM%%... 3.7 1.4 0.0 21 22 6.5 2.2 0.0 XMMMMF%%.. . 4.8 1.4 0.0 22 23 12.3 10.1 6.1 ASSMMMB FF%%... 7.8 6.2 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) 28-Aug-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000