Office Programs

The staff at the Weather Forecast Office (WFO) in Flagstaff maintains weather surveillance, warning, and forecast responsibilities for Northern Arizona.

Our primary mission is to protect life and property, and to promote the welfare and economy of the nation. We fulfill this mission by issuing various types of forecasts, watches, warning ,and advisories to keep you informed and prepared for the weather. We alert you when damaging or potentially life threatening weather occurs or is forecasted.

This mission is accomplished by the implimintation of several specialized office programs which include: Public, Aviation, Fire Weather, Hydrology, and Dissemination programs.

Return to WFO Flagstaff's Home Page.

Public Programs

Arizona County Warning Areas

With its primary mission being the protection of life and property, the NWS established a three-tiered program of warnings, watches, and advisories. This public warning program provides accurate and timely weather information before, during, and after a weather event so that you can make safe and informed decisions. Below is a brief explanation of our public program.

Warnings:When severe weather approaches your area, our forecasts become so short-term that we are actually "warning" you that a potentially life threatening event is about to happen and to put your protection plan into action. When we issue a warning it means that certain weather phenomena are occurring or imminent and that you should take immediate action to ensure your safety and minimize property loss. For a listing of warnings issued by the NWS Flagstaff click here.

Watches:The NWS issues watches up to 36 hours in advance of potentially hazardous weather, giving you plenty of time to plan ahead and protect yourself and your family. A watch means conditions are favorable for certain weather phenomena to occur but it is not expected immediately. Go about your normal activities, but be aware of rapidly changing weather conditions. For a listing of watches issued by the NWS Flagstaff click here.

Advisories:The NWS issues weather advisories to inform you of events that can become hazardous or result in significant impact to you and your family if caution is not exercised. For a listing of advisories issued by the NWS Flagstaff click here.

Forecasts:Our public forecasts are designed to help you plan your day or even your week. These forecasts are continually updated and refined 24 hours a day, seven days a week as new information is received by our highly trained staff of Meteorologists and Hydro-Meteorological Technicians. Public Zone Forecasts are generated and issued at least twice a day with updates as needed. The scheduled issuance times are 3:45 am/pm.

The "zones" in the Public Zone Forecasts are areas that represent similar geographic and/or climatological regions. The Flagstaff office provides specific forecasts for 19 zones in Northern Arizona. Zone Forecasts include detailed weather information for the first 48 hours and an extended period for 3 to 7 days. For a map of Arizona zones click here.

Weather can change rapidly at times, especially during the summer monsoon season. During rapidly changing weather events, we issue Short Term Forecasts which serve to keep you informed of detailed weather conditions in your area within the next 1 to 3 hours. Short Term Forecasts are issued to provide additional details such as timing and location of weather phenomena, and to complement the Public Zone Forecast.

Aviation

Our forecasters produce two types of aviation forecasts for general aviation purposes including flight planning and in-route operations. The Terminal Aviation Forecast (TAF) provides a concise 24 hour forecast for significant weather conditions which affect aviation operations within 5 statute miles of an airport. A Transcribed Weather Broadcast (TWEB) provides a concise 12 hour forecast for significant weather conditions which affect aviation operations along designated routes. These routes have 50 mile wide corridor which extends between to end points (airports).

At the Flagstaff WFO we prepare the following TAFs and TWEBs:

Aviators not only rely on forecasts, they use Meteorological Aviation Reports (METAR) to find out specific weather information at an airport for their operations. An observing system called Automated System Observation System (ASOS) or a trained weather observer produces observations once an hour or more frequently during rapidly changing weather events. Pilots can use radio signals to obtain data directly from the observing system at the end of the runway. The ASOS unit measures the following weather elements:

For a map of ASOS locations click here.

For additional information on the Aviation Program, please link to our Aviation Web page

Fire Weather

WFO Flagstaff produces fire weather forecasts, watches and Red Flag warnings for Northern Arizona. WFO Flagstaff also provides fire weather spot forecasts for a specific site for prescribed burns ignited on Federal Lands and for wildfires on Federal Lands or a non-Federal Land prescribed burn that is declared a wildfire.

During fire season special forecasts are prepared twice a day for users like the US Forest Service (USFS), Bureau of Land Management (BLM), Bureau of Indian Affairs, and Arizona State Land to help them determine how to fight wildfires and where potential starts may occur. Some specific items we forecast for include relative humidity changes, temperature changes, drainage and transport winds, haines index and lightning activity.

When significant weather conditions occur along with high to extreme fire danger, special watches and warnings are issued which address the potential for wild fires across Arizona. These watches and warnings are listed below.

For additional information on the Fire Weather Program, please link to our Fire Weather Web page.

Hydrology

Water is an important factor in our lives here in Northern Arizona. The NWS provides the official word for warnings, watches and other pertinent hydrologic information on water flow, flooding and flood potential on our areas waterways and land areas. We provide forecasts for certain locations on Oak Creek, the Little Colorado River, and the Puerco River.

The hydrologic forecast process starts at the NWS River Forecast Center located in Salt Lake City, Utah. Hydrologists collect data from various sources including river gages, SNOTEL gages, river staff gages, and various weather observations. Hydrologists quality control these data, then use these data (along with other data from agencies like the US Army Corp of Engineers, US Bureau of Reclamation, US Geological Survey, Arizona Department of Water Resources, and Natural Resource Conservation Service) in sophisticated computer programs to model streamflow, runoff, and snow ablation process . Hydrologists review the computer model output and refine the forecasts before making them available for use.

Because hydrologic concerns are complex across different geographic areas, the NWS has special positions at selected offices called Service Hydrologists. The Service Hydrologist who provides enhanced knowledge for our forecast area is located at the Phoenix NWS office. This person provides special forecasts like the Water Supply Outlook and Spring Flood Potential, and is responsible for establishing with each local community flood stages and forecast points on rivers.

The staff at the WFO Flagstaff interpret river forecasts and issue appropriate warnings, watches and statements when necessary. When flooding season begins, we prepare special statements and forecasts for selected points on our rivers. During certain times of the year, storms may cause quick bursts of rainfall which cause flash flooding. Our forecasters issue watches, warnings and statements during these events as well. We also issue appropriate statements in the unfortunate event of a dam failure.

For additional information on the Hydrology Program, please link to our Hydrology Web page.

Dissemination

NOAA Weather Radio

All of this information is highly useful and, at times, necessary for day-to-day planning, both at home and at work. But the information is only useful if it is available to you. Therefore, the most crucial aspect of our mission is the accurate and timely dissemination of this weather information. NOAA Weather Radio (NWR) is one of our main communication links to the people we serve. Warning and forecast information, current weather conditions, special public weather information and weather safety tips are all incorporated into our daily broadcasts which are available to you 24 hours a day, 7 days a week.

NOAA Weather Radio is a nationwide network of transmitters that reach 85 percent of our population. One such transmitter is located on Mt Elden in Flagstaff. This transmitter broadcasts continuous weather information over a 100 mile radius from Flagstaff. Several other NOAA Weather Radio transmitters broadcast across certain areas of Arizona. Specially designed radios can be purchased from commercial vendors so you can listen to NOAA Weather Radio . Some of these radios have special features that alarm when the NWS issues a warning. A simple scanner can also access these frequencies. Recently, some car manufactures have included these special frequencies on their radios.

For additional information on NOAA Weather Radio, link to our NOAA Weather Radio page.

Other Communication Methods

Another method of receiving our products is through private weather vendors who carry the NOAA Weather Wire. This is a service that disseminates all text products as well as certain images like Doppler Weather Radar and Satellite imagery. There are many commercial weather services that provide a wide variety of weather products and graphics. These types of services have a usage fee.

In the State of Arizona, certain public agencies like the Sheriff's Office, Arizona Department of Public Safety, etc. receive our text products through the Arizona State Criminal Justice Information System (ASCJIS).

NWS forecast and warning information can also be found on the Internet at our homepage.

For general weather information or other Earth Science issues these links may help:

Webmaster
US Dept of Commerce
National Oceanic and Atmospheric Administration
National Weather Service
Flagstaff Weather Forecast Office
P.O. Box 16057
Bellemont, AZ 86015-6057
http://weather.gov/flagstaff

Tel: (928) 556-9161