SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 2 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 28-32 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 14.7 12.5 7.2 SSSMMM BBFF%%%... 9.3 7.9 4.4 00 01 16.2 14.4 8.2 ASSSXM MMBBFF%%.. .. 10.2 9.4 4.8 01 02 16.0 15.6 8.7 SSSXX MMBBB%%%%. ... 10.3 10.2 5.1 02 03 15.5 16.3 9.0 SSSXX MMBBBP%%%. .... 10.4 10.7 5.3 03 04 14.7 16.5 9.1 SSSSX MMBBPP%%.. .. 9.8 10.9 5.4 04 05 14.5 16.3 9.0 SSSXX MMBBPP%%.. .. 9.6 10.8 5.3 05 06 14.1 15.7 8.8 SSSXX MBBBP%%... .. 9.4 10.4 5.1 06 07 14.0 14.6 8.2 ASSSXM MBBP%%%... .. 9.2 9.7 4.8 07 08 13.7 12.7 7.4 SSSXMM MBF%%%%... .. 9.1 8.5 4.3 08 09 13.5 9.2 5.6 SSXMMMM MFF%%%%... . 9.1 6.2 3.2 09 10 10.8 2.2 0.0 XMMMMMMMMF %%%%..... 7.6 1.4 0.0 10 11 8.5 2.2 0.0 XMMMMMMF%% %..... 6.0 1.4 0.0 11 12 7.4 2.2 0.0 XMMMMMF%%. .... 5.3 1.4 0.0 12 13 6.8 2.2 0.0 XMMMMM%%%. ... 4.9 1.4 0.0 13 14 6.5 2.2 0.0 XMMMMM%%.. .. 4.8 1.4 0.0 14 15 6.4 2.2 0.0 XMMMMF%%.. .. 4.7 1.4 0.0 15 16 6.3 2.2 0.0 XMMMMF%%.. .. 4.7 1.4 0.0 16 17 6.2 2.2 0.0 XMMMMF%%.. . 4.6 1.4 0.0 17 18 5.7 2.2 0.0 XMMMM%%%.. . 4.4 1.4 0.0 18 19 5.3 2.2 0.0 XMMMM%%%.. . 4.0 1.4 0.0 19 20 4.8 2.2 0.0 XMMM%%%... 3.5 1.4 0.0 20 21 4.5 2.2 0.0 XMMM%%%... 3.4 1.4 0.0 21 22 5.6 2.2 0.0 XMMMM%%... 4.3 1.4 0.0 22 23 11.3 8.5 5.3 SSMMMFF F%%... 7.0 4.5 3.4 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) 2-Aug-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000