SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 24 September, 2026 T-index: 45 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 14.7 13.9 7.9 ASSXXM MBBF%%%... 9.1 9.1 4.7 00 01 15.4 15.4 8.6 SSSXX MBBBB%%%.. . 9.3 10.2 5.1 01 02 15.6 16.4 9.1 SSSSX MBBBBP%%%. . 9.3 10.9 5.3 02 03 15.7 17.0 9.4 ASSSX XBBBBPP%%. .. 9.4 11.3 5.5 03 04 15.8 17.2 9.4 ASSSX XMBBBPP%%. .. 9.7 11.4 5.5 04 05 15.7 17.0 9.4 ASSSX XMBBBPP%%. .. 9.7 11.3 5.5 05 06 14.9 16.5 9.1 SSSSX MBBBPP%%.. . 9.4 11.0 5.3 06 07 14.4 15.6 8.7 ASSSXX MBBBP%%... . 9.1 10.4 5.0 07 08 14.1 14.1 8.0 ASSXXM MBBB%%%... 8.9 9.4 4.6 08 09 13.8 11.7 6.8 ASSXMMM BFF%%%%... 8.7 7.7 4.0 09 10 11.7 5.1 3.4 AMMMMMMM F%%%%%.... 7.9 0.0 2.5 10 11 9.4 2.1 0.0 XMMMMMMMM% %%%%..... 6.6 1.4 0.0 11 12 8.3 2.1 0.0 XMMMMMMM%% %%..... 6.0 1.4 0.0 12 13 7.7 2.1 0.0 XMMMMMM%%% %..... 5.5 1.4 0.0 13 14 7.5 2.1 0.0 XMMMMMM%%% .... 5.4 1.4 0.0 14 15 7.8 2.1 0.0 XMMMMMF%%% .... 5.4 1.4 0.0 15 16 7.6 2.1 0.0 XMMMMMF%%% ... 5.2 1.4 0.0 16 17 7.2 2.1 0.0 XMMMMMF%%. ... 5.1 1.4 0.0 17 18 6.5 2.1 0.0 XMMMMM%%.. .. 4.8 1.4 0.0 18 19 5.9 2.1 0.0 XMMMM%%%.. . 4.3 1.4 0.0 19 20 5.4 2.1 0.0 XMMMM%%... 4.0 1.4 0.0 20 21 5.5 2.1 0.0 XMMMM%%... 4.2 1.4 0.0 21 22 8.1 2.1 0.0 MMMMMMMF%% ... 5.6 0.0 2.0 22 23 12.6 11.3 6.7 ASSXMMB BF%%%.. 7.9 7.3 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) 24-Sep-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000