Mercer Island September Weather Averages Washington, United States of America

September Weather Averages for Mercer Island

High Temp	22°C	71°F
Low Temp	11°C	52°F
Avg Temp	16°C	61°F
Sunshine Hours	212 hours
Rainfall	79.22 mm	3.12 In
Rain days	7 days
Pressure	1016 mb	30 In

Mercer Island September Averages Year by Year

Year	High Temp	Low Temp	Avg Temp	Sunshine Hours	Rainfall	Rain days	Pressure
2009	22°C / 72°F	11°C / 52°F	16°C / 61°F	263 hours	75.10 mm / 2.96 In	6 days	1017 mb / 31 In
2010	20°C / 68°F	11°C / 52°F	15°C / 59°F	141 hours	114.94 mm / 4.53 In	12 days	1015 mb / 30 In
2011	24°C / 74°F	12°C / 53°F	17°C / 63°F	276 hours	40.80 mm / 1.61 In	5 days	1017 mb / 31 In
2012	23°C / 74°F	10°C / 51°F	16°C / 61°F	312 hours	7.80 mm / 0.31 In	2 days	1019 mb / 31 In
2013	21°C / 70°F	12°C / 53°F	16°C / 61°F	205 hours	202.80 mm / 7.98 In	12 days	1012 mb / 30 In
2014	23°C / 73°F	12°C / 53°F	17°C / 62°F	237 hours	56.10 mm / 2.21 In	4 days	1015 mb / 30 In
2015	20°C / 68°F	10°C / 50°F	15°C / 58°F	196 hours	38.00 mm / 1.50 In	6 days	1016 mb / 30 In
2016	20°C / 68°F	10°C / 50°F	14°C / 58°F	210 hours	69.70 mm / 2.74 In	6 days	1019 mb / 31 In
2017	23°C / 74°F	13°C / 55°F	17°C / 63°F	226 hours	77.50 mm / 3.05 In	8 days	1016 mb / 30 In
2018	21°C / 69°F	11°C / 52°F	15°C / 60°F	197 hours	62.30 mm / 2.45 In	6 days	1017 mb / 30 In
2019	20°C / 68°F	11°C / 53°F	15°C / 60°F	132 hours	134.90 mm / 5.31 In	11 days	1015 mb / 30 In
2020	25°C / 76°F	14°C / 57°F	19°C / 66°F	221 hours	108.70 mm / 4.28 In	7 days	1017 mb / 30 In
2021	21°C / 70°F	11°C / 51°F	15°C / 60°F	163 hours	113.11 mm / 4.45 In	11 days	1016 mb / 30 In
2022	24°C / 76°F	12°C / 53°F	17°C / 63°F	241 hours	7.30 mm / 0.29 In	0 days	1015 mb / 30 In
2023	21°C / 71°F	10°C / 50°F	15°C / 59°F	165 hours	79.28 mm / 3.12 In	5 days	1016 mb / 30 In

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