SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Perth district Date: 7 February, 2026 T-index: 125 Bearings: 0 180 Distance: 0-300 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 60-90 1E 40-90 1 5 10 15 20 25 30 35 40 ** NONE ** UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 6.2 3.1 2.7 AFFF%.. 00 01 6.7 3.4 3.0 AFFF%%.. 01 02 7.0 3.6 3.1 FFF%%.. 02 03 7.4 3.7 3.2 FFFF%%. 03 04 7.6 3.8 3.2 FFFF%%. . 04 05 7.7 3.8 3.2 FFFF%%. . 05 06 7.6 3.7 3.2 FFFF%%. . 06 07 7.4 3.5 3.0 AFFFF%%. . 07 08 7.3 3.3 2.9 AFFFF%%. 08 09 7.0 2.9 2.6 AFFF%%.. 09 10 7.0 2.4 2.2 FFFF%%.. 10 11 6.9 0.5 0.0 FFFFFF%%. 11 12 6.6 0.5 0.0 FFFFFF%.. 12 13 6.5 0.5 0.0 FFFFFF%.. 13 14 5.9 0.5 0.0 FFFFF%%. 14 15 5.6 0.5 0.0 FFFFF%.. 15 16 5.5 0.5 0.0 FFFFF%. 16 17 5.2 0.5 0.0 FFFFF%. 17 18 4.7 0.5 0.0 FFFF%.. 18 19 4.2 0.5 0.0 FFFF%. 19 20 3.9 0.5 0.0 FFF%% 20 21 3.8 0.5 0.0 FFF%% 21 22 4.5 1.8 1.7 AFF%. 22 23 5.6 2.7 2.4 FFF%.. 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) 7-Feb-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000