SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 20 May, 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 12-14 1E 2 1 5 10 15 20 25 30 35 40 2F 28-31 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 16.0 12.3 7.1 SSSMMM MBFFF%%%.. .. 10.2 7.7 4.3 00 01 17.8 14.3 8.1 ASSSXM MMMBFFF%%% ..... 11.2 9.3 4.8 01 02 17.6 15.5 8.6 SSSXX MMMBBFF%%% %.... 11.6 10.1 5.1 02 03 16.8 16.1 8.9 SSSXX MMMBBB%%%% %..... 11.1 10.6 5.3 03 04 16.5 16.3 9.0 SSSXX MMMBBB%%%% ..... 10.9 10.8 5.3 04 05 16.1 16.2 9.0 SSSXX MMMBBB%%%% ..... 10.8 10.7 5.3 05 06 16.3 15.5 8.7 SSSXX MMMBBF%%%% ..... 10.8 10.3 5.1 06 07 16.6 14.4 8.1 ASSSXM MMMBFF%%%% %..... 10.7 9.6 4.8 07 08 16.2 12.5 7.2 SSSXMM MMMFFF%%%% ...... 10.5 8.3 4.2 08 09 14.7 8.7 5.3 SSMMMMM MMFF%%%%.. ... 9.8 5.8 3.1 09 10 11.2 2.2 0.0 XMMMMMMMMF F%%%..... 7.9 1.4 0.0 10 11 9.0 2.2 0.0 XMMMMMMF%% %%..... 6.2 1.4 0.0 11 12 7.5 2.2 0.0 XMMMMMF%%% .... 5.3 1.4 0.0 12 13 7.0 2.2 0.0 XMMMMM%%%. ... 4.9 1.4 0.0 13 14 6.8 2.2 0.0 XMMMMM%%%. .. 4.8 1.4 0.0 14 15 6.4 2.2 0.0 XMMMMM%%.. .. 4.8 1.4 0.0 15 16 6.5 2.2 0.0 XMMMMM%%.. .. 4.8 1.4 0.0 16 17 6.4 2.2 0.0 XMMMMM%%.. .. 4.7 1.4 0.0 17 18 6.1 2.2 0.0 XMMMMM%%.. .. 4.5 1.4 0.0 18 19 5.8 2.2 0.0 XMMMM%%%.. .. 4.1 1.4 0.0 19 20 5.5 2.2 0.0 XMMMM%%%.. .. 3.8 1.4 0.0 20 21 5.1 2.2 0.0 XMMMM%%... . 3.8 1.4 0.0 21 22 6.2 2.2 0.0 XMMMMF%%.. . 4.5 1.4 0.0 22 23 12.4 8.0 5.0 SMMMMFF FF%%... 7.6 3.6 3.3 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) 20-May-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000