SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Perth district Date: 16 May, 2025 T-index: 90 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 6.8 2.3 2.0 AFFFF%.. 00 01 8.0 2.8 2.4 FFFFF%%. 01 02 8.6 3.1 2.6 AFFFFF%% . 02 03 8.9 3.3 2.7 AFFFFF%% . 03 04 8.8 3.3 2.7 AFFFFF%% . 04 05 8.8 3.3 2.7 AFFFFF%% . 05 06 8.9 3.2 2.6 AFFFFF%% . 06 07 8.9 3.0 2.5 AFFFFF%% .. 07 08 8.6 2.6 2.2 FFFFFF%. . 08 09 8.0 1.8 1.7 AFFFFF%%. 09 10 6.6 0.4 0.0 FFFFFF%.. 10 11 5.2 0.4 0.0 FFFFF%.. 11 12 4.3 0.4 0.0 FFFF%. 12 13 3.8 0.4 0.0 FFF%.. 13 14 3.7 0.4 0.0 FFF%. 14 15 3.6 0.4 0.0 FFF%. 15 16 3.6 0.4 0.0 FFF%. 16 17 3.5 0.4 0.0 FFF%. 17 18 3.4 0.4 0.0 FFF%. 18 19 3.3 0.4 0.0 FFF%. 19 20 3.3 0.4 0.0 FFF%. 20 21 3.0 0.4 0.0 FF%.. 21 22 3.2 0.4 0.0 FFF. 22 23 4.9 0.4 0.0 FFFF%. 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) 16-May-2025 BoM Space Weather Services, Sydney Australia +61-2-9213-8000