Mercer Island Weather History Washington, United States of America

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Thu 19 Mar, 2026 Weather in Mercer Island

Sunrise: 07:14 AM Sunset: 07:21 PM	Moonrise: 07:19 AM Moonset: 08:40 PM	Max: 12.6 °c	Min: 10.1 °c	Avg: 11.1 °c	Precip: 8.90 mm	Max Wind: 19.1 kph

	Thu 19 0:00 am	Thu 19 3:00 am	Thu 19 6:00 am	Thu 19 9:00 am	Thu 19 12:00 pm	Thu 19 3:00 pm	Thu 19 6:00 pm	Thu 19 9:00 pm
Icon
Temp	11.9°c	12.5°c	11.2°c	10.7°c	11.2°c	11.0°c	10.5°c	10.1°c
Wind	10.8 kmph	15.5 kmph	16.2 kmph	15.1 kmph	17.6 kmph	15.1 kmph	9.4 kmph	9.7 kmph
Precip	0.00 mm	0.00 mm	0.00 mm	0.00 mm	0.00 mm	0.00 mm	1.20 mm	1.90 mm
Cloud	98%	100%	100%	99%	99%	100%	100%	100%
Humidity	81%	72%	80%	85%	83%	90%	96%	98%
Pressure	1017 mb	1016 mb	1017 mb	1018 mb	1019 mb	1021 mb	1022 mb	1023 mb

Mercer Island Annual Weather Averages

Month	High Temp	Low Temp	Avg Temp	Sunshine Hours	Rainfall	Rain days	Pressure
January	7°C / 45°F	2°C / 36°F	4°C / 40°F	114 hours	177.96 mm / 7.01 In	12 days	1019 mb / 31 In
February	8°C / 46°F	2°C / 35°F	5°C / 40°F	89 hours	133.94 mm / 5.27 In	11 days	1018 mb / 31 In
March	11°C / 51°F	3°C / 37°F	6°C / 44°F	100 hours	153.31 mm / 6.04 In	13 days	1016 mb / 30 In
April	14°C / 57°F	5°C / 40°F	9°C / 48°F	116 hours	112.73 mm / 4.44 In	10 days	1017 mb / 31 In
May	18°C / 65°F	8°C / 46°F	13°C / 55°F	165 hours	77.67 mm / 3.06 In	8 days	1017 mb / 31 In
June	21°C / 70°F	10°C / 51°F	16°C / 60°F	180 hours	54.95 mm / 2.16 In	5 days	1016 mb / 30 In
July	26°C / 78°F	13°C / 56°F	19°C / 67°F	257 hours	14.95 mm / 0.59 In	2 days	1017 mb / 31 In
August	26°C / 78°F	14°C / 57°F	19°C / 67°F	261 hours	27.32 mm / 1.08 In	3 days	1016 mb / 30 In
September	22°C / 71°F	11°C / 53°F	16°C / 61°F	204 hours	72.93 mm / 2.87 In	6 days	1016 mb / 30 In
October	15°C / 60°F	8°C / 46°F	11°C / 52°F	162 hours	145.03 mm / 5.71 In	10 days	1017 mb / 31 In
November	10°C / 50°F	4°C / 40°F	7°C / 44°F	106 hours	211.99 mm / 8.35 In	14 days	1017 mb / 31 In
December	7°C / 44°F	2°C / 35°F	4°C / 39°F	98 hours	197.89 mm / 7.79 In	13 days	1018 mb / 31 In

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