Average Weather in January in Lafayette California, United States
Daily high temperatures increase by 3°F, from 53°F to 57°F, rarely falling below 47°F or exceeding 63°F.
Daily low temperatures increase by 2°F, from 40°F to 42°F, rarely falling below 32°F or exceeding 50°F.
For reference, on August 23, the hottest day of the year, temperatures in Lafayette typically range from 56°F to 79°F, while on January 1, the coldest day of the year, they range from 40°F to 53°F.
Average High and Low Temperature in January
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on January. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature in January
The month of January in Lafayette experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 55% throughout the month. The highest chance of overcast or mostly cloudy conditions is 56% on January 11.
The clearest day of the month is January 26, with clear, mostly clear, or partly cloudy conditions 47% of the time.
For reference, on January 11, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 56%, while on July 20, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 92%.
Cloud Cover Categories in January
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Lafayette, the chance of a wet day over the course of January is essentially constant, remaining around 26% throughout.
For reference, the year's highest daily chance of a wet day is 30% on February 20, and its lowest chance is 0% on July 24.
Probability of Precipitation in January
The average sliding 31-day rainfall during January in Lafayette is essentially constant, remaining about 3.3 inches throughout, and rarely exceeding 7.0 inches or falling below 0.3 inches.
Average Monthly Rainfall in January
Over the course of January in Lafayette, the length of the day is increasing. From the start to the end of the month, the length of the day increases by 42 minutes, implying an average daily increase of 1 minute, 23 seconds, and weekly increase of 9 minutes, 41 seconds.
The shortest day of the month is January 1, with 9 hours, 36 minutes of daylight and the longest day is January 31, with 10 hours, 18 minutes of daylight.
Hours of Daylight and Twilight in January
The latest sunrise of the month in Lafayette is 7:24 AM on January 5 and the earliest sunrise is 11 minutes earlier at 7:13 AM on January 31.
The earliest sunset is 5:00 PM on January 1 and the latest sunset is 31 minutes later at 5:30 PM on January 31.
Daylight saving time is observed in Lafayette during 2018, but it neither starts nor ends during January, so the entire month is in standard time.
For reference, on June 21, the longest day of the year, the Sun rises at 5:46 AM and sets 14 hours, 48 minutes later, at 8:34 PM, while on December 21, the shortest day of the year, it rises at 7:20 AM and sets 9 hours, 32 minutes later, at 4:52 PM.
Sunrise & Sunset with Twilight in January
The chance that a given day will be muggy in Lafayette is essentially constant during January, remaining around 0% throughout.
For reference, on September 7, the muggiest day of the year, there are muggy conditions 0% of the time, while on January 1, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in January
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Lafayette is essentially constant during January, remaining within 0.1 miles per hour of 7.0 miles per hour throughout.
For reference, on June 21, the windiest day of the year, the daily average wind speed is 9.7 miles per hour, while on November 1, the calmest day of the year, the daily average wind speed is 6.7 miles per hour.
The lowest daily average wind speed during January is 6.9 miles per hour on January 21.
Average Wind Speed in January
Wind Direction in January
Lafayette is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.
The average surface water temperature in Lafayette is essentially constant during January, remaining around 53°F throughout.
The lowest average surface water temperature during January is 53°F on January 17.
Average Water Temperature in January
While it does not do so every year, freezing temperatures are seen in Lafayette over some winters. The day least likely to be in the growing season is December 28, with a 51% chance.
Time Spent in Various Temperature Bands and the Growing Season in January
The average accumulated growing degree days in Lafayette are gradually increasing during January, increasing by 40°F, from 0°F to 40°F, over the course of the month.
Growing Degree Days in January
The average daily incident shortwave solar energy in Lafayette is gradually increasing during January, rising by 0.6 kWh, from 2.2 kWh to 2.8 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in January
For the purposes of this report, the geographical coordinates of Lafayette are 37.886 deg latitude, -122.118 deg longitude, and 584 ft elevation.
The topography within 2 miles of Lafayette contains very significant variations in elevation, with a maximum elevation change of 928 feet and an average elevation above sea level of 516 feet. Within 10 miles contains very significant variations in elevation (2,949 feet). Within 50 miles contains large variations in elevation (4,324 feet).
The area within 2 miles of Lafayette is covered by artificial surfaces (59%) and grassland (19%), within 10 miles by artificial surfaces (42%) and grassland (28%), and within 50 miles by grassland (22%) and water (21%).
This report illustrates the typical weather in Lafayette year round, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There are 3 weather stations near enough to contribute to our estimation of the temperature and dew point in Lafayette.
For each station, the records are corrected for the elevation difference between that station and Lafayette according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at Lafayette is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Lafayette and a given station.
The stations contributing to this reconstruction are: Buchanan Field Airport (47%, 13 kilometers, northeast); Oakland International Airport (31%, 20 kilometers, southwest); and Livermore Municipal Airport (22%, 34 kilometers, southeast).
Time zones for aiports and weather stations are provided by AskGeo.com .