Climate Across Places

Select a variable for the data. Definitions are provided below.

Precipitation

• Total Precipitation: Total amount of water that falls from the atmosphere as rain, snow, or other forms of precipitation during a specified period. Higher precipitation can mean wetter conditions and increased water availability, while lower precipitation can contribute to dry conditions and water shortages. 

Snow

• Precipitation as Snow: Amount of precipitation that falls as snow during a specified period. This data people understand winter conditions and the amount of precipitation that may contribute to seasonal snowpack. 

• Maximum Annual Snow Water Equivalent: Highest total amount of water contained in the snowpack during a year, also known as snow water equivalent (SWE). A higher SWE indicates more water stored in the snowpack, which can provide a greater water supplies when the snow melts but may also contribute to increased runoff. 

• Percent of Precipitation as Snow: Percentage of total precipitation that falls as snow. This can help show whether an area is receiving more of its precipitation as snow or rain. 

• Snow: Total amount of water contained within the snowpack during a specified month. This helps track how much water is being stored throughout the winter and when the snowpack beings to accumulate or decline. It can be useful in recreation, agriculture, and ecosystem management. 

• Water Year Day of Maximum Annual Snow Water Equivalent: Calendar Day within a water year when the snowpack contains its highest total amount of water. This indicates when the snowpack reaches its annual peak and can help show whether peak snowpack is occurring earlier or later in the water year. 

Temperature

• Average Temperature: Mean temperature recorded over a specified period of time. Average temperature provides a general picture of the climate conditions experienced in an area. 

• Maximum Temperature: Highest temperature recorded over a specified period of time. This helps identify the hottest conditional an area experience. It can be useful for assessing heat stress, planning for energy demand, managing crops and livestock and understanding impacts on ecosystems. 

• Minimum Temperature: Lowest temperature recorded over a specified period of time. Minimum temperature helps identify the coldest conditions an area experiences. 

• Frost Days: Annual number of days when the minimum temperature is less than 32°F (0°C). Frost days are important for agriculture and gardening because freezing temperatures can damage or kill sensitive plants. This information can also help identify changes in growing seasons and frost risk.

• Frost Free Period: Measure the local growing season by counting the parts of the year where the odds of frost are low. Gardeners use this to pick plants that mature before the cold returns.

• Growing Degree Days (5°C): Measures and tracks the amount of heat energy an organism, experiences over time to determine when a crop will sprout, flower or reach harvest maturity. Growing Degree Days (GDD) help farmer and gardeners make precises decisions based on the real-time weather. 

• Icing Days: Annual number of days when the highest recorded temperature does not exceed 32°F. These are days when temperatures remain at or below freezing throughout the day. Icing days can affect roads, transportation, infrastructure, agriculture, and daily activities and can help indicate the severity and persistence of winter conditions.

• Monthly Maximum of Daily Temperature: Average of the daily maximum temperatures within a month. This shows the typical daytime high temperature for each month. Farmers, gardeners, energy planners, and outdoor recreation managers can use this information to understand seasonal heat conditions and how they may change over time.

• Monthly Minimum of Daily Temperature: Average of the daily minimum temperatures within a month. This shows the typical nighttime or early-morning low temperature for each month. It can help farmers and gardeners understand frost risk, help communities plan for heating needs, and provide insight into changes in overnight temperatures.

Extreme Precipitation

• Annual Count Precipitation ≥ 20 mm/day: Number of days in a year when daily precipitation is greater than or equal to 20 mm. This helps identify how frequently heavy precipitation events occur. Communities and emergence managers can use this information when considering flood risk, stormwater management, and infrastructure needs. 

• Annual Maximum 1-Day Precipitation: Highest amount of precipitation recorded within a single day. This helps identify the most intense one-day precipitation event expected in a year.

• Annual Maximum 5-Day Precipitation: Highest amount of precipitation recorded within a 5-day period. This helps identify periods when large amounts of precipitation accumulate over serval days. 

• Annual Total Precipitation When Daily > 95th Percentile: Total annual precipitation occurring on days when daily precipitation exceeds the 95th percentile of baseline wet days. This shows how much of the year's precipitation comes from unusually wet events. It can help communities and water managers understand whether precipitation is becoming more concentrated in heavy events rather than being spread more evenly throughout the year.

• Max Consecutive Days Precipitation < 1 mm/day: Maximum number of consecutive days with precipitation less than 1 mm per day. Longer periods can indicate extended dry conditions and may contribute to drought, reduced soil moisture, increased irrigation needs, and stress on crops and vegetation.

• Max Consecutive Days Precipitation > 1 mm/day: Maximum number of consecutive days with precipitation greater than 1 mm per day. Longer wet periods can lead to saturated soils, increased runoff, flooding, and challenges for agriculture, construction, and transportation.

• Simple Precipitation Intensity Index: Annual average precipitation intensity on days with more than 1 mm of precipitation. This helps show how heavily precipitation falls when it occurs. Higher intensity can result in more rapid runoff and may increase the potential for flooding, erosion, and soil loss.

Extreme Temperature

• Annual Days Heat Index 80–90°F: Number of days each year when the heat index reaches the 80–90°F caution range. The heat index accounts for both temperature and humidity to describe how hot conditions feel to the human body. This information can help communities, outdoor workers, event planners, and public health officials identify periods when additional heat precautions may be needed.

• Annual Days Heat Index 90–105°F: Number of days each year when the heat index reaches the 90–105°F extreme caution range. More days in this range indicate increased exposure to potentially hazardous heat.

• Annual Days Heat Index 105–130°F: Number of days each year when the heat index reaches the 105–130°F danger range. These conditions represent dangerous heat that can place significant stress on the human body. Communities and public health officials can use this information when planning for heat emergencies, cooling centers, outdoor activities, and worker safety.

• Annual Days Heat Index Over 130°F: Number of days each year when the heat index exceeds 130°F, indicating the extreme danger range. These conditions represent exceptionally severe heat and can pose serious risks to human health. Information about these events can help communities prepare for extreme heat emergencies and identify areas that may need additional resources or planning.

• Annual Days Maximum Temperature >85°F: Number of days in a year when the maximum temperature is higher than 85°F.This provides an indication of how often an area experiences warm or hot days.

• Annual Days Maximum Temperature >90°F: Number of days in a year when the maximum temperature is higher than 90°F. More days above 90°F indicate more frequent hot conditions. This information can help communities, employers, farmers, and public health officials prepare for increased heat exposure, water demand, and energy use.

• Annual Days Maximum Temperature >95°F: Number of days in a year when the maximum temperature is higher than 95°F. This indicates how frequently an area experiences very hot days. It can be useful for evaluating heat stress, crop and livestock impacts, energy demand, water use, and the need for heat preparedness.

Select the desired spatial resolution for the climate data.

• 9 Kilometer Cell Size: Each grid cell covers an area of 9 km × 9 km.

Select the years you want to use for each time period. You can choose years from 1981 through 2099.

• Historic: Select years representing past or historical climate data.

• Near Term: Select years representing the near-term future.

• Future: Select years representing the longer-term future.

• Time periods can overlap, allowing you to use the same years in more than one period.

To return to the original year ranges, select Reset to Defaults.

Select the desired timescale for the data. Available timescales vary by variable and may include annual, monthly, or seasonal data.

• Annual: Data summarized over a full year. For most variables, the annual period follows the Water Year, from October 1 through September 30. The exceptions are Growing Degree Days and Frost-Free Periods, which follow the calendar year from January 1 through December 31.

• Monthly: Data summarized for each individual calendar month, from January through December.

• Seasonal: Data summarized over a three-month season. Seasons are grouped as Winter (December–February), Spring (March–May), Summer (June–August), and Fall (September–November).

Global Climate Models (GCMs) are tools used to project how climate conditions may change in the future.

Ensemble: A collection of climate model simulations that use slightly different starting conditions to produce a range of plausible future climate outcomes. Ensembles help show the natural variability and uncertainty in climate projections and can support planning and decision-making.

Scenarios: Climate scenarios describe different possible future climate conditions based on changes in temperature, precipitation, snow, and other climate factors. Each scenario represents a different combination of projected climate conditions and can be used with ensemble data to explore a range of potential impacts.

• Hot & Smokey: Represents a warmer mid-century future, with global temperatures increasing by approximately 5.4°F (3°C). This scenario is characterized by more frequent hot conditions and a significant increase in smoky summer days. Precipitation remains highly variable, while warmer temperatures can cause earlier snowmelt, increased evaporation, and reduced late-summer water availability. Rain-on-snow events and rapid spring snowmelt may also increase flood risk.

• Warm Refuge: Represents a moderately warmer mid-century future, with global temperatures increasing by approximately 3.6°F (2°C) above late-19th-century temperatures. Warmer conditions combined with slightly lower precipitation increase the likelihood of low-snow years. Earlier snowmelt and rain-on-snow events may affect the timing and availability of water and increase the potential for flooding.

• Shrinking Snowpack: Represents a warmer mid-century future, with global temperatures increasing by approximately 3.6°F (2°C) above late-19th-century temperatures. Although precipitation increases slightly, warmer temperatures cause more precipitation to fall as rain rather than snow, particularly during the fall and spring. This results in a greater likelihood of low-snow years and a declining snowpack, which can shift the timing of water availability and increase pressure on late-season water supplies.

Different scenarios can be selected to compare projected climate conditions and understand how impacts may change under different levels of future warming.

There are three ways to select an area for the data:

• Point: Click directly on the map to select the location where you want the data to come from.

• Draw Area: Select the drawing tool, click to create points around your desired area, and double-click to finish drawing. To restart,

• simply press the draw polygon button again.

• Boundary: Select from predefined geographic or hydrologic boundaries below. 

Spatial Elements

State Boundaries

• County: Official U.S. County boundaries.

Federal Boundaries

• U.S. Climate Divisions: Divides the U.S. into distinct climatic regions based on geographic and climate characteristics.

• Ranger Districts: Divides national forests and grasslands into 600+ districts established by the U.S. Forest Service.

Watersheds

• HUC 4 Watersheds: Hydrologic Unit Code level that divides the U.S. into 245 subregions.

• HUC 8 Watersheds: Hydrologic Unit Code level that divides the U.S. into approximately 2,400 subbasins.

• HUC 10 Watersheds: Hydrologic Unit Code level that divides the U.S. into approximately 19,000 watersheds.

• HUC 12 Watersheds: Hydrologic Unit Code level that divides the U.S. into approximately 105,000 subwatersheds.

Show or Hide: Select the eye icon to show or hide the climate layer on the map.

Transparency: Use the slider to adjust the transparency of the climate layer. Move the slider to make the layer more or less transparent.

Raw: The original data for the selected year or location, without averaging or adjustments.

30-yr Avg: The average value over a 30-year period. The 30-year period moves forward by one year for each new value. For example, the 1997 value is the average from 1981–2011, while the next value uses 1982–2012.

Δ vs. Historic: Shows the difference between the selected value and the historical average. A positive value means the selected value is higher than the historical average, while a negative value means it is lower.