SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 17 September, 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 12-16 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 15.8 13.9 8.0 ASSXMM MBBFF%%%.. . 9.6 9.0 4.7 00 01 16.7 15.5 8.7 SSSXX MMBBBF%%%% ... 10.0 10.2 5.1 01 02 16.7 16.5 9.2 SSSSX MMBBBB%%%% ... 9.9 10.9 5.4 02 03 16.8 17.1 9.5 ASSSX XMBBBBP%%. ... 10.0 11.3 5.5 03 04 16.8 17.3 9.6 ASSSX XMBBBBP%%. ... 10.2 11.5 5.6 04 05 16.6 17.1 9.5 ASSSX XMBBBBP%%. .. 10.2 11.4 5.5 05 06 15.6 16.6 9.2 SSSSX XMBBBP%%.. .. 9.7 11.1 5.4 06 07 14.9 15.6 8.8 SSSXX MBBBP%%%.. . 9.3 10.5 5.1 07 08 14.7 14.1 8.0 ASSXXM MBBB%%%%.. . 9.2 9.4 4.7 08 09 14.4 11.5 6.8 ASSXMMM MFFF%%%... . 9.0 7.6 4.0 09 10 12.2 2.2 0.0 MMMMMMMMMM FF%%%%.... . 8.2 0.0 2.1 10 11 9.6 2.2 0.0 XMMMMMMMM% %%%%..... 6.7 1.4 0.0 11 12 8.5 2.2 0.0 XMMMMMMM%% %%..... 6.1 1.4 0.0 12 13 7.9 2.2 0.0 XMMMMMM%%% %..... 5.7 1.4 0.0 13 14 7.8 2.2 0.0 XMMMMMM%%% %.... 5.5 1.4 0.0 14 15 8.1 2.2 0.0 XMMMMMMF%% .... 5.4 1.4 0.0 15 16 7.8 2.2 0.0 XMMMMMF%%% .... 5.3 1.4 0.0 16 17 7.4 2.2 0.0 XMMMMMF%%% ... 5.2 1.4 0.0 17 18 6.6 2.2 0.0 XMMMMM%%%. .. 4.9 1.4 0.0 18 19 6.0 2.2 0.0 XMMMM%%%.. . 4.4 1.4 0.0 19 20 5.5 2.2 0.0 XMMMM%%... 4.0 1.4 0.0 20 21 5.5 2.2 0.0 XMMMM%%... 4.1 1.4 0.0 21 22 8.1 2.2 0.0 XMMMMMFF%% ... 5.5 1.4 0.0 22 23 13.1 11.1 6.6 ASSXMMB BFF%%... 8.2 7.1 4.0 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) 17-Sep-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000