(Note: The following is an edited excerpt from K-State Research and Extension Publication MF3337, National Weather Service Forecasts: Serving Agriculture. – Kathy Gehl, Agronomy eUpdate Editor)
The Great Plains is known for rapidly changing weather. Checking weather forecasts is a daily ritual for residents of the central United States as they determine if they should prepare for calm seasonable weather, or for severe storms, extreme blasts of cold, deadly blizzards, roller-coaster temperatures, blistering hot days, extended droughts, and torrential downpours.
With today’s instant communication, individuals can directly access National Weather Service’s (NWS) weather and forecast products from a mobile device or the internet. These forecasts provide farmers, ranchers, and land managers the information they need to make decisions regarding safety in severe weather, help maximize the use of farm inputs, and minimize production risks.
NWS forecast products predict weather conditions ahead for the next seven days. Forecasts contain multiple weather variables, including: air temperature, dew point temperature, relative humidity, wind speed, wind direction, rainfall or frozen precipitation, and sky cover. Forecasts predict a value or indicate the probability of precipitation for specific geographical areas.
For example, what does a chance of rain mean?
The “chance” is the likelihood of measurable precipitation that is at least 0.01 of an inch of rain at a location during a specific time period (usually 3, 6, or 12 hours). The “chance of rain” is also called probability of precipitation.
A 40 percent chance of rain means there is a 40 percent chance your location will receive at least 0.01 of an inch of rain during the specified time period.
A minimum of 0.01 of an inch is needed. If the conditions are right, a location could receive as much as several inches of rain with only a forecast of 20 percent chance of rain.
Mobile Device Access: mobile.weather.gov
To access NWS forecasts on a mobile device, enter “mobile.weather.gov” into your mobile device’s browser app. On the landing page, enter a city and state or ZIP code. Entered locations are automatically saved for quick forecast access. Touching the “Go” button brings up the location, any special weather statement or hazardous weather advisory, and current conditions (Figure 1). The statement or advisory includes a warning symbol that provides detailed information. The “+” symbol in the “Current Conditions” box brings up additional weather data and details about the observed location.
Scroll down to see next viewable box, “Forecast” (Figure 1). It includes forecast information for the next 36 hours, navigation arrows to advance or backup the forecast, plus symbols to go to hourly forecasts, and a “Detailed Forecast” that provide more information.
Figure 1. NWS mobile.weather.gov
To dig deeper into the forecast, the “Forecast” box offers a number of options. Use the arrows to move forward to see day and night forecasts for up to 7 days. Touching the “+” button in the box for any day or night displayed brings up the hour-by-hour forecast (Figure 2). The hourly forecasts include: general weather, temperature, wind direction, and wind speed.
Figure 2. NWS - mobile.weather.gov - Local hour-by-hour screen
The NWS’s full website is weather.gov. Users have the choice of viewing point forecasts for a single location or seeing nationwide forecast maps. The weather.gov homepage shows all active watches and warnings on maps of the United States (Figure 3).
Figure 3. NWS homepage on August 30, 2017 - weather.gov
The weather.gov homepage is an interactive map that allows users to select their local NWS office’s forecast homepage. Select an area on the map to go to the home webpage for that local office (Figure 4). There are 122 local forecast offices across the continental United States. Local NWS office forecast office homepages vary. The page may include one or more “Graphicasts” or “Weather Story” items. These are regional weather graphics that highlight weather of note or concern. Other products on the page include local radar, weather maps, and text and icon product selection.
Figure 4. NWS - Local office webpage
Users can click a specific area on local office’s interactive map to access a “Point Forecast” webpage.
The “Point Forecast” webpage lists the local office toward the top of the page. If there are any hazardous weather statements or advisories, they are listed next in red highlights. Below that are weather data from the closest National Weather Service weather station. After that is a day and night capsule forecast covering the next 5 days and nights (Figure 5).
Figure 5. NWS - Point Forecast webpage
Scrolling down the page brings up the “Detailed Forecast” for the next 7 days. This is a text forecast that often includes information on wind speeds, gusts, precipitation timing, precipitation amounts, and changes from rain to frozen precipitation.
Farther down the page are the “Hourly Weather Forecast” graphs (Figure 6). This is one of the most powerful forecast tools available. It provides time series graphs of hourly forecast weather variables over a 48-hour period. Variables that can be graphed, include: temperature, wind, relative humidity, rain, thunder, and other types of selected weather variables. An interactive time and date box can be used to start the graph from any date and hour to view hourly forecasts for as long as 7 days. Users can turn off or on weather variables or conditions listed above the graphs or graph legend.
Figure 6. NWS - Hourly weather graphs
The time series shows how temperatures will change over the day or when a cold front is coming through. The wind graph shows shifts and if the change occurs during times of high wind speed. Graphs show when there is a chance of precipitation and whether it will come as rain or as frozen precipitation. Yellow shaded boxes show likely rainfall or frozen precipitation amounts over hours covered by each box, if precipitation occurs. Grey shading indicates nighttime hours and white, daytime hours.
The NOAA NWS is constantly seeking to improve forecast accuracy and weather product delivery. They produce a wide variety of quality products that can help farmers and ranchers improve their operation’s management.
Peter Tomlinson, Environmental Quality Specialist
Mary Knapp, Assistant State Climatologist
Albert Sutherland, Oklahoma Mesonet Agriculture Coordinator, Oklahoma State University
Lana Barkman, former Great Plains Grazing Extension Project Coordinator
Erin Maxwell, NOAA NWS, Norman Forecast Office
Todd Lindley, NOAA NWS, Norman Forecast Office
(This publication is based upon work supported by: U.S. Department of Agriculture, Project Nos. 2013-69002-23146 through the National Institute for Food and Agriculture’s Agriculture and Food Research Initiative, Regional Approaches for Adaptation to and Mitigation of Climate Variability and Change. Great Plains Grazing is a group of research scientists, Extension specialists, and consumer experts from Kansas State University, Oklahoma State University, University of Oklahoma, Tarleton State University, Samuel Roberts Noble Foundation, and the USDA’s Agricultural Research Service working together to improve and promote regional beef production while mitigating its environmental footprint.)