| 13:53 PST |  Mostly Cloudy | 4°C / 39°F | 1°C / 34°F | 81% | 1023 mb (30.21 in) | Calm | - | 10SM |
| | KSEA 222153Z 00000KT 10SM FEW018 BKN025 BKN040 04/01 A3020 RMK AO2 SLP236 T00440006 |
| 13:35 PST |  Overcast | 4°C / 39°F | 1°C / 34°F | 81% | 1022 mb (30.18 in) | SSW 6 kph (SSW 3.5 mph) | - | 10SM |
| | KSEA 222135Z 24003KT 10SM FEW018 BKN027 OVC039 04/01 A3019 RMK AO2 |
| 12:53 PST |  Overcast | 4°C / 39°F | 1°C / 34°F | 81% | 1022 mb (30.18 in) | Calm | - | 10SM |
| | KSEA 222053Z 00000KT 10SM FEW009 SCT018 OVC039 04/01 A3018 RMK AO2 SLP229 T00440011 51016 |
| 11:53 PST |  Overcast | 4°C / 39°F | 1°C / 34°F | 81% | 1022 mb (30.18 in) | Calm | - | 10SM |
| | KSEA 221953Z 00000KT 10SM FEW009 SCT017 OVC043 04/01 A3017 RMK AO2 SLP226 T00390011 |
| 10:53 PST |  Mostly Cloudy | 3°C / 37°F | 1°C / 34°F | 87% | 1021 mb (30.15 in) | SSE 7 kph (SSE 4.6 mph) | - | 10SM |
| | KSEA 221853Z 15004KT 10SM FEW008 SCT016 BKN042 03/01 A3014 RMK AO2 SLP217 T00280011 |
| 10:38 PST |  Mostly Cloudy | 3°C / 37°F | 1°C / 34°F | 87% | 1021 mb (30.15 in) | S 7 kph (S 4.6 mph) | - | 10SM |
| | KSEA 221838Z 17004KT 10SM FEW008 BKN016 BKN042 03/01 A3015 RMK AO2 |
| 09:53 PST |  Mostly Cloudy | 3°C / 37°F | 2°C / 36°F | 93% | 1020 mb (30.12 in) | SSE 7 kph (SSE 4.6 mph) | - | 10SM |
| | KSEA 221753Z 16004KT 10SM FEW022 BKN041 BKN200 03/02 A3013 RMK AO2 SLP213 60002 T00280017 10028 20011 51039 |
| 09:15 PST |  Mostly Cloudy | 3°C / 37°F | 1°C / 34°F | 87% | 1020 mb (30.12 in) | SE 11 kph (SE 6.9 mph) | - | 10SM |
| | KSEA 221715Z 12006KT 10SM FEW013 SCT022 BKN039 03/01 A3011 RMK AO2 |
| 08:53 PST |  Mostly Cloudy | 3°C / 37°F | 2°C / 36°F | 93% | 1019 mb (30.09 in) | Variable 6 kph (Variable 3.5 mph) | 0.00 mm (0.00 in) | 10SM |
| | KSEA 221653Z VRB03KT 10SM FEW013 BKN021 BKN039 03/02 A3010 RMK AO2 RAB15E48 SLP201 P0000 T00280017 |
| 07:53 PST |  Overcast | 3°C / 37°F | 1°C / 34°F | 87% | 1018 mb (30.06 in) | Calm | - | 10SM |
| | KSEA 221553Z 00000KT 10SM FEW012 BKN027 OVC032 03/01 A3006 RMK AO2 SLP188 T00280011 |
| 06:53 PST |  Mostly Cloudy | 2°C / 36°F | 1°C / 34°F | 93% | 1016 mb (30 in) | Calm | - | 10SM |
| | KSEA 221453Z 00000KT 10SM SCT015 BKN023 02/01 A3001 RMK AO2 SLP173 60002 T00220011 51029 |
| 06:42 PST |  Mostly Cloudy | 2°C / 36°F | 1°C / 34°F | 93% | 1016 mb (30 in) | Calm | - | 10SM |
| | KSEA 221442Z 00000KT 10SM BKN015 BKN046 02/01 A3001 RMK AO2 |
| 05:53 PST |  Mostly Cloudy | 2°C / 36°F | 1°C / 34°F | 93% | 1016 mb (30 in) | Calm | 0.25 mm (0.01 in) | 10SM |
| | KSEA 221353Z 00000KT 10SM FEW010 BKN046 02/01 A2999 RMK AO2 RAE09 SLP163 P0001 T00220006 |
| 05:19 PST |  Overcast | 2°C / 36°F | 1°C / 34°F | 93% | 1015 mb (29.97 in) | Calm | 0.25 mm (0.01 in) | 10SM |
| | KSEA 221319Z 00000KT 10SM FEW010 SCT015 OVC044 02/01 A2997 RMK AO2 RAE09 P0001 |
| 04:53 PST |  Overcast Light Rain | 2°C / 36°F | 1°C / 34°F | 93% | 1015 mb (29.97 in) | WNW 6 kph (WNW 3.5 mph) | 0.25 mm (0.01 in) | 9SM |
| | KSEA 221253Z 29003KT 9SM -RA SCT010 BKN016 OVC021 02/01 A2996 RMK AO2 RAB25 SLP153 P0001 T00220006 |
| 04:36 PST |  Overcast Light Rain | 3°C / 37°F | 1°C / 34°F | 87% | 1014 mb (29.94 in) | S 6 kph (S 3.5 mph) | 0.00 mm (0.00 in) | 8SM |
| | KSEA 221236Z 17003KT 8SM -RA BKN016 OVC022 03/01 A2994 RMK AO2 RAB25 P0000 |
| 03:53 PST |  Overcast | 3°C / 37°F | 1°C / 34°F | 87% | 1014 mb (29.94 in) | S 7 kph (S 4.6 mph) | 0.00 mm (0.00 in) | 10SM |
| | KSEA 221153Z 17004KT 10SM BKN013 BKN020 OVC026 03/01 A2993 RMK AO2 RAE42 SLP143 P0000 60000 70014 T00280006 10033 20028 52027 |
| 03:26 PST |  Overcast Light Rain | 3°C / 37°F | 1°C / 34°F | 87% | 1013 mb (29.91 in) | SSE 11 kph (SSE 6.9 mph) | 0.00 mm (0.00 in) | 10SM |
| | KSEA 221126Z 16006KT 10SM -RA BKN017 BKN022 OVC028 03/01 A2991 RMK AO2 P0000 |
| 02:53 PST |  Overcast Light Rain | 3°C / 37°F | 1°C / 34°F | 87% | 1013 mb (29.91 in) | SSE 13 kph (SSE 8.1 mph) | 0.00 mm (0.00 in) | 8SM |
| | KSEA 221053Z 16007KT 8SM -RA BKN011 OVC019 03/01 A2990 RMK AO2 RAB09E20B37 SLP134 P0000 T00280011 |
| 01:53 PST |  Overcast | 3°C / 37°F | 1°C / 34°F | 87% | 1012 mb (29.88 in) | SSE 9 kph (SSE 5.8 mph) | - | 10SM |
| | KSEA 220953Z 16005KT 10SM BKN011 OVC018 03/01 A2987 RMK AO2 SLP124 T00280006 |
| 01:31 PST |  Overcast | 3°C / 37°F | 1°C / 34°F | 87% | 1011 mb (29.85 in) | S 11 kph (S 6.9 mph) | - | 10SM |
| | KSEA 220931Z 17006KT 10SM OVC015 03/01 A2986 RMK AO2 |
| 00:53 PST |  Overcast | 3°C / 37°F | 1°C / 34°F | 87% | 1011 mb (29.85 in) | S 15 kph (S 9.2 mph) | - | 10SM |
| | KSEA 220853Z 19008G17KT 10SM BKN013 OVC019 03/01 A2985 RMK AO2 SLP116 T00330006 52013 |
| 00:35 PST |  Overcast | 3°C / 37°F | 1°C / 34°F | 87% | 1010 mb (29.83 in) | S 17 kph (S 10.4 mph) | - | 10SM |
| | KSEA 220835Z 19009KT 10SM OVC013 03/01 A2984 RMK AO2 |