Alert: NWS Weather Alert Godot Data Class Reference

Alert is a typed Resource that holds all data for a single active NWS weather alert — such as a Tornado Warning, Flood Watch, or Winter Storm Advisory. An array of these resources is emitted by the alerts_fetched signal after calling Nws.fetch_alerts(). Alerts are scoped to the county zone of the configured location. The array may be empty if no alerts are active.

class_name Alert
extends Resource

The ends field may be an empty dictionary if the NWS did not specify a definite end time for the alert. Always check ends.is_empty() before using it. The instruction field may be an empty string for some alert types. The replacedBy and replacedAt fields are only set when this alert has been superseded by a newer one.

Fields

Identification

String

The unique identifier for this alert, assigned by the NWS (e.g. "urn:oid:2.49.0.1.840.0.abc123..."). Use this to track specific alerts across fetches or to match against references.

raw

Dictionary

The complete, unmodified JSON properties object for this alert as returned by the NWS API. Useful for accessing any fields not explicitly mapped by Alert.

Event & Classification

event

String

The type of weather event being alerted, such as "Tornado Warning", "Flood Watch", "Winter Storm Advisory", or "Special Weather Statement". This is the primary field for identifying what kind of alert has been issued.

Value	Meaning
`"Actual"`	A real, operational alert
`"Exercise"`	Part of a drill or exercise
`"System"`	A system-generated message
`"Test"`	A test message
`"Draft"`	A draft not yet in effect

Value	Meaning
`"Alert"`	Initial issuance of a new alert
`"Update"`	Updates and supersedes a previous alert
`"Cancel"`	Cancels a previous alert before its expiry
`"Ack"`	Acknowledgement message
`"Error"`	Error notification

Severity & Urgency

severity

String

The severity of the hazard. Valid values in descending order of severity:

Value	Meaning
`"Extreme"`	Extraordinary threat to life or property
`"Severe"`	Significant threat to life or property
`"Moderate"`	Possible threat to life or property
`"Minor"`	Minimal to no known threat
`"Unknown"`	Severity not reported

certainty

String

How certain the forecaster is that the hazard will occur. Valid values:

Value	Meaning
`"Observed"`	Already occurring
`"Likely"`	Probability > 50%
`"Possible"`	Probability ≤ 50%
`"Unlikely"`	Not expected to occur
`"Unknown"`	Certainty not reported

urgency

String

How quickly action is needed. Valid values:

Value	Meaning
`"Immediate"`	Responsive action should be taken immediately
`"Expected"`	Responsive action should be taken soon (within the hour)
`"Future"`	Responsive action should be taken in the near future
`"Past"`	Responsive action is no longer required
`"Unknown"`	Urgency not reported

Timeline

sent

Dictionary

A Godot time dictionary representing when the alert message was transmitted by the NWS. Contains keys: year, month, day, hour, minute, second, weekday, dst.

effective

Dictionary

A Godot time dictionary for when the alert became (or becomes) effective. In the same format as sent.

onset

Dictionary

A Godot time dictionary for when the hazard is expected to begin affecting the area. In the same format as sent.

expires

Dictionary

A Godot time dictionary for when the alert expires if not cancelled or updated first. In the same format as sent.

ends

Dictionary

A Godot time dictionary for the definite end of the hazard, if one was specified. May be an empty dictionary ({}) when the NWS did not set a definite end time. Always check alert.ends.is_empty() before using this field.

Message Content

headline

String

A brief headline summarizing the alert, such as "Tornado Warning issued for Travis County until 8:15 PM CDT".

capitalHeadline

String

An alternate headline sourced from the NWSheadline parameter in the alert, which may differ in phrasing from headline. Typically written in all-caps style by NWS offices. May be empty if the alert does not include this parameter.

description

String

The full body text of the alert, containing all details about the hazard, its expected impacts, and affected areas. This is the primary field to show in an expanded alert detail view.

instruction

String

Recommended protective actions that the public should take in response to the alert (e.g. "Move to an interior room on the lowest floor of a sturdy building."). May be an empty string for some alert types.

response

String

A shorter suggested response to the alert (e.g. "Shelter", "Evacuate", "Prepare", "Execute"). Suitable for use in compact UI elements.

Sender

sender

String

The email address or identifier of the NWS office that issued the alert (e.g. "w-nws.webmaster@noaa.gov").

senderName

String

The human-readable name of the NWS office that issued the alert (e.g. "NWS Austin/San Antonio TX").

Supersession

references

Array[String]

An array of alert IDs that this alert updates or cancels. Empty if this is a fresh "Alert" message type with no prior references.

replacedBy

String

The ID of the alert that superseded this one. Only set if this alert has been replaced by a newer message. Empty string otherwise.

replacedAt

String

The time string indicating when this alert was replaced. Only set alongside replacedBy. Empty string otherwise.

Usage example

func _ready():
    Nws.setup(35.4676, -97.5164)
    Nws.location_setup_complete.connect(_on_location_ready)

func _on_location_ready():
    Nws.alerts_fetched.connect(_on_alerts)
    Nws.fetch_alerts()

func _on_alerts(alerts: Array[Alert]):
    if alerts.is_empty():
        print("No active alerts.")
        return

    for alert in alerts:
        # Skip anything that isn't a real operational alert
        if alert.status != "Actual":
            continue

        print("=== ", alert.event, " ===")
        print("Severity: ", alert.severity, " | Certainty: ", alert.certainty,
              " | Urgency: ", alert.urgency)
        print("Issued by: ", alert.senderName)
        print("Headline: ", alert.headline)
        print("Onset: %04d-%02d-%02d %02d:%02d" % [
            alert.onset["year"], alert.onset["month"], alert.onset["day"],
            alert.onset["hour"], alert.onset["minute"]
        ])

        if not alert.ends.is_empty():
            print("Ends: %04d-%02d-%02d %02d:%02d" % [
                alert.ends["year"], alert.ends["month"], alert.ends["day"],
                alert.ends["hour"], alert.ends["minute"]
            ])

        if alert.instruction != "":
            print("What to do: ", alert.instruction)

Always filter by alert.status == "Actual" before displaying alerts to users. Test and exercise alerts are issued regularly by NWS offices and should not be shown as real emergencies.

Sort alerts by severity before displaying them. Use a helper that maps "Extreme" → 4, "Severe" → 3, "Moderate" → 2, "Minor" → 1, "Unknown" → 0 and call alerts.sort_custom(func(a, b): return severity_rank(a) > severity_rank(b)).

Singleton (Nws)

Data Classes

Alert: NWS Weather Alert Godot Data Class Reference

Fields

Identification

Event & Classification

Severity & Urgency

Timeline

Message Content

Sender

Supersession

Usage example

Build docs developers (and LLMs) love

Singleton (Nws)

Data Classes

Documentation Index

​Fields

​Identification

​Event & Classification

​Severity & Urgency

​Timeline

​Message Content

​Sender

​Supersession

​Usage example

Build docs developers (and LLMs) love

Fields

Identification

Event & Classification

Severity & Urgency

Timeline

Message Content

Sender

Supersession

Usage example