| 06:53 PST |  Mostly Cloudy Fog | -1°C / 30°F | -1°C / 30°F | 100% | 1028 mb (30.36 in) | NE 6 kph (NE 3.5 mph) | - | 1/4SM |
| | KSEA 241453Z 05003KT 1/4SM R16C/1200V4000FT FZFG BKN001 M01/M01 A3037 RMK AO2 TWR VIS 2 SLP293 T10061006 58007 |
| 06:14 PST |  Obscured Fog | 1°C / 34°F | 0°C / 32°F | 93% | 1028 mb (30.36 in) | NE 7 kph (NE 4.6 mph) | - | 1/2SM |
| | KSEA 241414Z 05004KT 1/2SM R16C/3000VP6000FT FG VV001 01/00 A3037 RMK AO2 |
| 06:09 PST |  Mostly Cloudy Fog | 0°C / 32°F | -1°C / 30°F | 93% | 1028 mb (30.36 in) | NE 9 kph (NE 5.8 mph) | - | 1SM |
| | KSEA 241409Z 05005KT 1SM R16C/3000VP6000FT BCFG BKN002 00/M01 A3037 RMK AO2 VIS N-E 1/2 |
| 06:00 PST |  Mostly Cloudy Fog | 1°C / 34°F | -1°C / 30°F | 87% | 1029 mb (30.39 in) | NE 9 kph (NE 5.8 mph) | - | 3SM |
| | KSEA 241400Z 04005KT 3SM R16C/5000VP6000FT BCFG BKN002 01/M01 A3038 RMK AO2 VIS N-E 1/2 |
| 05:53 PST |  Partly Cloudy Fog And Mist | 1°C / 34°F | -1°C / 30°F | 87% | 1028 mb (30.36 in) | NE 11 kph (NE 6.9 mph) | - | 4SM |
| | KSEA 241353Z 04006KT 4SM R16C/5000VP6000FT BR SCT002 SCT150 01/M01 A3037 RMK AO2 SLP296 T00061006 |
| 04:53 PST |  Partly Cloudy Fog And Mist | 1°C / 34°F | -1°C / 30°F | 87% | 1029 mb (30.39 in) | NE 9 kph (NE 5.8 mph) | - | 5SM |
| | KSEA 241253Z 04005KT 5SM BR FEW002 01/M01 A3038 RMK AO2 SLP299 T00061006 |
| 04:03 PST |  Partly Cloudy Fog And Mist | 1°C / 34°F | 0°C / 32°F | 93% | 1029 mb (30.39 in) | NNE 6 kph (NNE 3.5 mph) | - | 5SM |
| | KSEA 241203Z 02003KT 5SM BR SCT002 01/00 A3038 RMK AO2 |
| 03:53 PST |  Mostly Cloudy Fog And Mist | 1°C / 34°F | 0°C / 32°F | 93% | 1029 mb (30.39 in) | Calm | - | 1 1/2SM |
| | KSEA 241153Z 00000KT 1 1/2SM BR BKN002 01/00 A3039 RMK AO2 SFC VIS 4 SLP299 T00110000 10033 20006 58007 |
| 03:45 PST |  Mostly Cloudy Fog And Mist | 2°C / 36°F | 1°C / 34°F | 93% | 1029 mb (30.39 in) | Calm | - | 1 1/2SM |
| | KSEA 241145Z 00000KT 1 1/2SM BR BKN002 02/01 A3039 RMK AO2 SFC VIS 5 |
| 02:53 PST |  Partly Cloudy Fog And Mist | 2°C / 36°F | 1°C / 34°F | 93% | 1029 mb (30.39 in) | NNE 7 kph (NNE 4.6 mph) | - | 6SM |
| | KSEA 241053Z 02004KT 6SM BR FEW005 SCT150 02/01 A3040 RMK AO2 SLP305 T00170006 |
| 01:53 PST |  Mostly Cloudy | 2°C / 36°F | 1°C / 34°F | 93% | 1029 mb (30.39 in) | NE 6 kph (NE 3.5 mph) | - | 7SM |
| | KSEA 240953Z 03003KT 7SM FEW005 BKN150 02/01 A3040 RMK AO2 SLP305 T00220011 |
| 00:53 PST |  Mostly Cloudy | 3°C / 37°F | 1°C / 34°F | 87% | 1030 mb (30.42 in) | NE 7 kph (NE 4.6 mph) | - | 7SM |
| | KSEA 240853Z 05004KT 7SM FEW005 BKN150 03/01 A3041 RMK AO2 SLP306 T00280011 58007 |