Issaquah (WA) Temperatures: Monthly Averages and Year-Round Insights
On this page, we’ll explore Issaquah’s temperature statistics in detail, including day and night variations and monthly averages. We’ll also compare the annual temperature to other cities in the United States of America.
Monthly Temperature Averages
In Issaquah, temperatures differ significantly between summer and winter months. Average maximum daytime temperatures reach a comfortable 24°C in July. In December, the coolest month of the year, temperatures drop to a chilly 6°C. At night, minimum temperatures can drop even lower, averaging around 1°C.
The chart below illustrates the average maximum day and minimum night temperatures in Issaquah by month:
The lowest temperatures typically occur between 4 AM and 6 AM, while the peak temperatures are generally observed around 3 PM, when the sun's heating is most intense. July, the city’s warmest month, enjoys 312 hours of sunshine.
The chart below shows the average temperature throughout the year:
December, the city’s coldest month, receives about 196 mm of rainfall spread over roughly 22 days. For more information, please visit our Issaquah Precipitation page.
Annual Temperatures in the United States of America Compared
The map below shows the annual temperature across the United States of America. You can also select the different months in case you are interested in a specific month.
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Issaquah Temperatures Compared World Wide
Issaquah’s average annual maximum temperature is 15°C. Let’s compare this with some popular tourist destinations:
In Lisbon, Portugal, the average annual temperature is 21°C, offering warm summers and mild, rainy winters.
Meanwhile, Queenstown, New Zealand, the average annual temperature is significantly lower at 10°C, with mild summers and cold winters.
Chicago, USA, has a significant seasonal range, with an average annual temperature of 15°C.
Adelaide, Australia, enjoys warm summers and mild winters, with an average annual temperature of 21°C.
How does the temperature feel?
Humidity is an essential factor in how you experience temperature. When a warm period is accompanied by high humidity, it results in a higher perceived temperature. This is especially true when temperatures exceed 25°C, as it can cause greater discomfort.
On the other hand, in cooler months, especially when temperatures dip below 10°C, high humidity can intensify the cold. This makes the air feel much colder than it really is.
In Issaquah, during the coolest month, December, you will experience 80% humidity, which is considered very high. This is accompanied by an average maximum temperature of 6°C. In the warmest month, July, the humidity is 65% combined with an average maximum temperature of 24°C, which creates a high-feel temperature. Explore our detailed page on humidity levels for further details.
How are these Temperatures Measured?
Generally, temperature data depicting climate is usually given over a 30-year average in order to reduce short-term fluctuations and reveal better long-term trends in climate conditions.
This temperature data is taken from land-based thermometers, ocean buoys, ships, and satellites. These measurements are transmitted to weather stations and climate centers around the globe where they are processed, averaged, and analyzed in order to monitor the trends and create climate models.
Effects of Temperature on Weather and Climate
Temperature variations influence precipitation patterns in Amsterdam:
Rainfall: Warm air holds more moisture, leading to heavier rain during warmer months. However, precipitation is generally moderate year-round.
Snow: Occasional snowfall occurs in winter, though it rarely lasts very long.
For more detailed information about Issaquah’s weather, including monthly rainfall, sunshine hours, and humidity levels, visit our Issaquah climate page.
Current temperature in Issaquah (WA)
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