Any attributes not listed on this page should not be in use, they are in beta and might be deprecated or changed at a later date.

Severe Weather Events Category Subscriptions

Our API provides standardized severe weather events from many sources that can be compiled for "situational awareness", allowing managers to monitor the whole picture across all types of local, regional, and national alerts.

In addition to subscribing to any of the Severe Weather Events below, you can create Custom Insight conditions based on any of the data points listed in subscribed Data Layers, such that an event will trigger whenever they are met.

Accessing Severe Weather Events

Quickly access Severe Weather Events using our Events API and get prepared before a Severe Weather Event happens.

Event Title

Various weather conditions have different levels of risk. Therefore, the title of our predefined categories use the common multi-tier system mentioned below. It is highly recommended to follow this standard as well when defining your custom insights.

These are the common level, in increasing order:




Issued daily to indicate that a hazardous event may occur in the next seven days and is intended to provide information to those who need considerable lead time to prepare for the event.


Issued when a hazardous event is occurring, imminent, or likely (generally greater than 80% probability of occurrence), of a "less serious" nature such that may cause significant inconvenience, and if caution is not exercised could threaten life or property.


Issued when an event that by itself cannot pose a threat to life or property, but may indirectly cause other events to happen that may pose a threat to life or property.


Issued when the risk of a hazardous event has increased significantly, (50 to 80% certainty that warning thresholds will be met) but its occurrence, location, or timing is still uncertain and is intended to provide enough lead time to set plans in motion can do so.


Issued when a hazardous event is occurring, imminent, or likely (generally greater than 80% probability of occurrence), thereby posing a threat to life or property.


Issued as a follow-up message to a warning, watch, or emergency, that may update, extend, or cancel the message it is following up or a notification of significant weather for which no type of advisory, watch, or warning exists.

Event Description

Usually, when reporting a weather event the following are expected to be described:

  • WHAT is going to happen?
  • WHERE will it take place?
  • WHEN will it occur?
  • IMPACTS that can be expected?
  • ACTIONS precautionary or in preparedness needed?

It is common and recommended to note each with a preceding asterisk and three periods affixed, such as * WHAT..., for improved readability.

Below is an example of a weather announcement description, as reported by the NWS:

* WHAT...For the High Surf Warning, dangerously large breakingwaves of 10 to 15 feet expected in the surf zone. For the HighRip Current Risk, dangerous rip currents expected.* WHERE...In Alabama, Mobile Coastal and Baldwin CoastalCounties. In Florida, Escambia Coastal and Santa Rosa CoastalCounties.* WHEN...For the High Surf Warning, from 6 AM Wednesday to 6 PMCDT Thursday. For the High Rip Current Risk, through Thursdayafternoon.* IMPACTS...Breaking waves can sweep people off jetties anddocks, and into dangerous seas. Life-threatening swimmingconditions and significant beach erosion can be expected. Ripcurrents can sweep even the best swimmers away from shore intodeeper water.

Event Severity

The code denoting the intensity of impact:




Extraordinary threat to life or property


Significant threat to life or property


Possible threat to life or property


Minimal to no known threat to life or property


Severity unknown

Event Urgency

The code denoting the time available to prepare:




Responsive action SHOULD be taken immediately


Responsive action SHOULD be taken soon (within next hour)


Responsive action SHOULD be taken in the near future


Responsive action is no longer required


Urgency not known

Event Certainty

The code denoting the confidence in the observation or prediction:




Determined to have occurred or to be ongoing


Likely (p > ~50%)


Possible but not likely (p <= ~50%)


Not expected to occur (p ~ 0)


Certainty unknown

Event Response

An action code denoting the appropriate handling:




Take shelter in place or as instructed


Relocate as instructed


Make preparations as instructed


Execute a pre-planned activity as instructed


Avoid the subject event as instructed


Attend to information sources as instructed


Evaluate the information in this message

All Clear

The subject event no longer poses a threat or concern, follow-up as instructed


No action recommended

Event Instruction

A text details the extended human-readable instructions, for example: "Slow down and use caution while traveling. The latest road conditions for the state you are calling from can be obtained by calling 5 1 1."

Event Geocodes and Locations

geocodes is an array of geographically-based strings that describe the event target area, as mentioned in the geocodeType attribute, whereas location is a GeoJSON Geometry representing the entire coverage area (can be a Point, Polygon or MultiPolygon).