What is a Weather Hazard?

Severe weather hazards such as hurricanes, tornadoes, thunderstorms, hail, flooding, winds, winter weather, and more are dangerous weather phenomena that threaten life and property. Many of these phenomena are related to atmospheric conditions that can be monitored and forecast; an important task because weather hazards impact public safety and the economy. The National Weather Service (NWS) is responsible for issuing forecasts, watch and warning products for a variety of weather and water hazards.

Note: The descriptions in this section are informational only. Please see the NWS website for official information on all NWS topics. See NWS Weather-Ready Nation.

Impact Weather

A combination of observational datasets and numerical models are used in the warning process to identify and monitor all hazards. Once forecasters are highly confident that a specific weather scenario will cause significant impacts, they issue a warning as far in advance as possible for the areas expecting to be affected. The forecasters have the important and tedious role of sifting through a mountain of data, to determine what’s important before issuing the warning. It's not just the weather that is important, it’s the hazard’s impact as well.


Currently, forecasters must use multiple programs to issue hazardous warning products, depending on the type of event. The NWS uses some 122 different types of watches, warnings and advisories for various weather phenomena. The variety of products issued by the NWS is indicated by different colors on a US map where, for example, lime green on this map represents a flooding threat for certain areas. Even for meteorologists, the list of NWS products can be overwhelming.

Click image for current US Hazards and see the associated help map color legend.

NWS Hazards Map Spring 2019
  Example of NWS past Hazards page. Click image for current NWS Hazards.

   What is Hazard Services?

About Hazard Services

Hazard Services (HS) is a multi-year, multi-phase effort involving many project partners to produce a powerful software package that modernizes how hazardous weather products are generated by the NWS. This new forecast and hazard creation software on the Advanced Weather Interactive Processing System (AWIPS) workstation will replace three existing applications, each with its own interface, menu list, and process to create a forecast or weather warning. By combining these applications into one framework with a single interface, the forecasting process will be streamlined with a unified information creation workflow that is highly configurable and customizable.

"Our goal is to give the best possible tools to enable the weather service to apply those as skillfully as they do, to give the best possible warnings." Craig McLean, NOAA Oceanic and Atmospheric Research, October 2019.

HS Unifying tools

Picture of the new Hazard Services application (on right) that upgrades and replaces three legacy AWIPS warning tools.

Adopting Hazard Services provides the following benefits:
• A common interface for information creation that will minimize the amount of training needed for handling different weather phenomena
• The ability to produce a variety of output formats for flexible dissemination across different communication platforms
• A robust python framework that allows for the development of science-driven tools and recommenders to improve the forecast and warning-decision making process
• Flexible configuration framework to meet the current and future demands of dissemination and decision support requirements
• Foster improved collaboration between the NWS, NCEP National Centers, and its stakeholders
• Allows for rapid adoption of social-science driven messaging improvements and consolidation, such as the efforts by the Hazard Simplification (HazSimp) program

Leading-edge Science

Actionable information is meaningful information that is useful to decision-making or problem-solving. Criteria for actionable information -- the information is timely, relevant, and credible with a high level of accuracy. When fully realized and released, the HS application will serve as a conduit for leading-edge science and continue to get better.

   Project Development

Developers Website

Looking for technical information, see Useful links for Hazard Services Community (July 2020)

Design Basics

HS has been structured and designed by software engineers alongside Weather Forecast Office (WFO) Forecasters, Hydrologists, NWS Information Technology Officers (ITOs) and Science and Operations Officers (SOOs), and others who routinely issue watches, warnings, and advisories. It has a display with user features that include logical and functional design considerations. In 2019, the system was in beta released to the NWS, in a limited number of offices for evaluation and feedback.

Three Pillars of Development

HS developers at GSL are focused on three program areas: Weather Forecast Offices (WFOs), National Centers (NCs), and Forecasting a Continuum of Environmental Threats (FACETs).

Hazard Services for Weather Forecast Offices (WFOs)

The initial stages of HS development is focused on migrating the weather alerting capabilities of local NWS WFOs from their three AWIPS legacy applications into this unified framework. The migration is occurring on hazard-by-hazard basis with the first version of HS focused on a complete migration of the Hydrology hazards (e.g., river flooding, flash flooding, areal flooding).

HS Version 2 will focus on long-duration winter weather hazards (e.g., blizzards, winter storms, ice storms, and wind chill hazards) and phase 1 of the HazSimp messaging and consolidation process for Hydrology hazards. Version 3 will focus on long-duration marine (e.g., gale, smoke/fog, freezing spray, small craft) and non-precipitation (e.g., heat, cold/frost, fog, ashfall) weather hazards. Version 4 will focus on short-fuse convective hazards (e.g., severe thunderstorm, tornado, special marine warnings). Version 5 will focus on fire weather and civil emergencies.

Path I

NWS Weather Forecast Offices (WFO)

Hazard Services for National Centers (NCs)

The NOAA National Centers for Environmental Prediction (NCEP) have identified HS as a vehicle to aid their software transition from the National Center AWIPS (N-AWIPS) platform to AWIPS. While a push to migrate NCs over to HS will occur near the end of the HS WFO development process, work is already underway identifying and documenting how NCs produce and disseminate hazardous weather forecasts and products over much larger space and time scales than what is typically performed by a NWS WFO.

In addition, smaller transition activities are underway with the funding support of the NOAA Office of Weather and Air Quality (OWAQ) program — Joint Technology Transfer Initiative (JTTI) and NOAA's National Center office to upgrade mission-critical systems on an expedited timeline. Current NC workflows being investigated include the Weather Prediction Center’s (WPC) excessive rainfall outlook and mesoscale precipitation discussion and Ocean Prediction Center’s (OPC) high seas warning. Current NC endeavours being implemented into HS on an expedited schedule include the AIRMET, International SIGMET, and Volcanic Ash Advisory for the Alaska Aviation Weather Unit.

Path II

NCEP National Centers (NC) & Meteorological Watch Offices (MWO)

Hazard Services for Forecasting a Continuum of Environmental Threats (FACETs)

FACETs and Probabilistic Hazard Information (PHI) provides the ability for weather information to be disseminated with probabilistic information derived from high-resolution modelling and climatologies to produce an enhanced layer of information for core partners and stakeholders. PHI is meant to communicate clear and simple hazardous weather information to serve the public and get the desired results to take action when required. HS is the mechanism for FACETs and PHI concepts to be realized and evaluated.

By using Threats-In-Motion (TIM) concept, for example, it has warning grids that update with-in minutes and move continuously with the path of the storm. TIM has the advantage of providing useful lead times for locations downstream. PHI includes this and other future-looking probabilistic information. The current emphasis focused on an evolution of the severe thunderstorm and tornado warnings have been subject to evaluation at NOAA’s Hazardous Weather Testbed for the past three years.

These endeavours have been supported by a NOAA OWAC JTTI award.

Path III

Probabilistic Hazard Information (PHI)

Applied Case with Customization Tools

Two inches of snow on the Washington DC Beltway at rush hour will be treated very differently than in rural Nebraska. Each of the three legacy applications independently created ways for the local forecaster to customize communication of hazard conditions. Instead of writing code for each scenario, we have built an HS framework that allows users to shape the system to their requirements. It is based on the easy-to-learn Python programming language for users to customize functionality and add new capabilities. This allows the system to handle diversity in requirements across forecast domains like a WFO or MWO as well as extend to new areas.

Featured Articles

• Weather Whisperer, NWS Des Moines: Improving Hazard Communication Aug 07, 2016

From GSL Communications Office:
GSL hosts forecasters to evaluate new Hazard Services Features July 16, 2019
Experimental Hazard Services system tested in flash flood forecasting environment Jul 16, 2015

Additional Objectives

The NWS is striving to ensure that the public is aware of and prepared for the variety of weather- and water-based hazards we experience across the country every day. A project called Hazard Simplification, or Haz Simp, is an NWS project (independent of HS) that will help. This involves a review and improvements in the areas of communication, namely: clear and focused messages, terms people understand, impact-based warning, and flexible output.

Note: This Haz Simp description is informational only. Please see the NWS website for official information on all NWS topics and see the Haz Simp Project.

Clear and Focused Messages

Hazard Simplification will help make hazard messaging as clear and focused as possible. HS is one of the vehicles to make necessary "repair and revamp" message changes guided by the Haz Simp project, where "repair" refers to a smaller hazard messaging change, and "revamp" refers to a larger change.

Terms People Understand

The NWS, and thus HS, are implementing these changes by consolidating and reformatting products.
– Consolidation means reducing the number of Watch, Warning, and Advisory (WWA) hazard products. Example.
– Reformatting means shortening, focusing, and clarifying the body text within the WWA messages. Example.

A What, Where, When (WWW) wording offers a shorter message, following a standard format to address the What, Where, and When of the hazard and recommended precautionary/preparedness actions.

Impact-Based Warning

HS will use Impact-based Warning (IBW) wording to communicate threats. It will focus on providing more information to media and emergency managers, facilitating improved public response and decision making; and meeting societal needs in the most life-threatening weather events. The impact-based warning will have tornado threat information attached to it as a quick means to provide users and partners with potential high impact signals that prompt faster risk assessment and protective action. Read more here, IBW.

Flexible Output

As a modernized platform, HS will allow for flexible output (legacy text, xml, kml, common alerting protocol (CAP), shape files, etc.), probabilistic and deterministic information, and will lay the foundation for moving the NWS deeper into the Impact-Based Decision Support Services, IDSS, and FACETs eras.

   Hazard Services Products (Example)

Here is a discussion of a hazard product, the warning message—a text product.
Note: Hazard Services is now operational.

Text Products

The information in the local text products includes location-specific forecast parameters for each hazard that also includes what, where, when, how much, how long, and it will contain descriptions of potential impacts.

Initial Test of Hazard Services

A development milestone was achieved with HS on 4/19/2019. An operational product was issued and transmitted from the NWS WFO Omaha (OAX) AWIPS HS. This was a real river flood product (or flood statement, called FLS) that was coordinated with the AWIPS Program Office, the AWIPS Network Control Facility (NCF), and NWS Central Region (CR) HQ. The transmission and dissemination was tracked to ensure it was distributed appropriately. This was the first end-to-end test of this type for HS. Everything worked well!

This test was one of several checks to prepare for the nation-wide deployment of HS in the future.

HS Initial Test of Text Message

Hazard Services Technical Details

If there is a significant desire to understand the complex process, then press button for a more in-depth discussion about the technical details. To keep this discussion simpler, skip to the next section.

Winter Weather

This series of images shows the gritty details. Here is an example of a meteorological threat or warning identified in an NWS tool (GFE) and brought into the HS application. The warning used in the example is a "winter weather" hazard warning.

This image shows how the current AWIPS CAVE GFE user interface is used to identify and define a winter warning A), with controls (left side), and the associated display (right side).

HS Winter Weather image A

In this image, on the left, B) shows the HS user interface. The defined winter hazard event is a winter storm warning. And, the image of a Winter Storm Warning text product on the right C) is an example of the type of warning message to be disseminated—a text product.

HS Winter Weather image B and C

Project Partners

The Hazard Services program is a joint effort between many partners...
— NOAA NWS Forecast Offices (WFO)
— AWIPS-2 Program Office
— NOAA NWS National Center Collaborators
— NOAA/OAR/ESRL/Global Systems Laboratory (GSL)
— Cooperative Institute for Research in the Atmosphere (CIRA) at Colorado State University (CSU)
— Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado-Boulder (UCB)
— Cooperative Institute for Mesoscale Meteorological Studies (CIMMS) at the University of Oklahoma (OU)
— Raytheon AWIPS — Omaha, NE
— NOAA National Severe Storms Laboratory (NSSL)
— NOAA's Warning Decision Training Division (WDTD)
— and more

Global Systems Division


Raytheon logo

Raytheon Omaha

NOAA logo

AWIPS-2 Program Office

CIRA logo


CIRES logo

CIRES at CU-Boulder

NSSL logo


NWS logo


Generic people icon image

and, other partners and collaborators.

   Contact Information

Hazard Services Project Managers

HS Project Manager, and
NWS Project Manager at GSL

Darrel Kingfield photo

National Centers
Project Manager

Nate Hardin photo...

Project Manager

Kevin Manross photo