> ## Documentation Index
> Fetch the complete documentation index at: https://mtaapi.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# mta.alerts.current() — active MTA service alerts
> Reference for mta.alerts in mta-js. Retrieve current MTA service alerts—delays, planned work, and route suspensions—for subway or bus.
The `mta.alerts` namespace surfaces active MTA service alerts pulled from the agency's GTFS-Realtime alerts feed. Use `mta.alerts.current` to retrieve delays, planned service changes, and route suspensions for either the subway or bus network, filtered to only what's happening right now.
## `mta.alerts.current(params)`
Returns all active service alerts for the specified transit mode. Alerts include human-readable header and description text, affected routes, a severity classification, and the time window during which the alert applies.
### Parameters
The transit mode to fetch alerts for. Accepted values are `'subway'` or `'bus'`. Pass `'subway'` to get alerts affecting subway routes, or `'bus'` to get alerts affecting bus routes.
### TypeScript signature
```typescript theme={null}
type AlertMode = 'subway' | 'bus'
interface AlertsCurrentParams {
mode: AlertMode
}
interface ServiceAlert {
id: string
headerText: string
descriptionText: string
affectedRoutes: string[]
severity: string
startTime: number // Unix timestamp (seconds)
endTime: number | null // null if the alert has no scheduled end
}
interface AlertsCurrentResponse {
alerts: ServiceAlert[]
}
mta.alerts.current(params: AlertsCurrentParams): Promise
```
### Response fields
An array of active service alerts for the requested mode, ordered by `startTime` descending. Returns an empty array if there are no active alerts.
The unique identifier for this alert, assigned by the MTA.
A short summary of the alert, suitable for display in a list or notification.
The full alert body with details about affected service and any alternative instructions.
An array of route IDs impacted by this alert (for example, `['A', 'C', 'E']`).
The severity level of the alert. See the severity table below for possible values and their meanings.
The Unix timestamp (in seconds) when the alert becomes or became active.
The Unix timestamp (in seconds) when the alert is scheduled to end, or `null` if no end time has been set.
### Severity values
The `severity` field uses the following string values, from least to most severe:
| Value | Meaning |
| -------------- | -------------------------------------------------------- |
| `'INFO'` | General informational notice with no service impact. |
| `'WARNING'` | Minor disruption; service is affected but operating. |
| `'SEVERE'` | Significant disruption such as major delays or reroutes. |
| `'NO_SERVICE'` | The affected route or portion of it is suspended. |
`'NO_SERVICE'` alerts often accompany planned weekend work or emergency shutdowns. Filter on this severity value to surface outages that require riders to seek alternative routes.
### Code example
```typescript theme={null}
import { MTA } from 'mta-js'
const mta = new MTA({ apiKey: process.env.MTA_API_KEY })
const response = await mta.alerts.current({ mode: 'subway' })
const severe = response.alerts.filter(
(alert) => alert.severity === 'SEVERE' || alert.severity === 'NO_SERVICE'
)
for (const alert of severe) {
console.log(`[${alert.severity}] ${alert.headerText}`)
console.log(`Affected routes: ${alert.affectedRoutes.join(', ')}`)
console.log(alert.descriptionText)
console.log('---')
}
```
### Example response
```json theme={null}
{
"alerts": [
{
"id": "lmm:planned_work:127307",
"headerText": "A trains skip Howard Beach–JFK Airport",
"descriptionText": "Due to track maintenance, A trains will not stop at Howard Beach–JFK Airport (A27) from 11:30 PM Friday to 5 AM Monday. Take the AirTrain from Jamaica station as an alternative.",
"affectedRoutes": ["A"],
"severity": "WARNING",
"startTime": 1748991000,
"endTime": 1749214800
},
{
"id": "lmm:service_change:130841",
"headerText": "No F trains between 47–50 Sts–Rockefeller Ctr and Jay St–MetroTech",
"descriptionText": "F trains are suspended between 47–50 Sts–Rockefeller Ctr and Jay St–MetroTech due to an emergency signal repair. Use the A, C, or E trains as alternatives.",
"affectedRoutes": ["F"],
"severity": "NO_SERVICE",
"startTime": 1748994600,
"endTime": null
}
]
}
```
## OpenAPI
````yaml GET /api/v1/alerts
openapi: 3.0.3
info:
title: MTA API
description: Managed, API-key protected access to MTA realtime and static data.
version: 0.1.0
servers:
- url: https://www.mtaapi.dev
description: Production
security:
- bearerAuth: []
- apiKeyAuth: []
tags:
- name: subway
description: Subway realtime data
- name: bus
description: BusTime realtime data
- name: alerts
description: Service alerts
- name: stops
description: Route-aware static GTFS stop lookup
- name: system
description: Health and database status
paths:
/api/v1/alerts:
get:
tags:
- alerts
summary: Get current service alerts
operationId: getApiV1Alerts
parameters:
- name: mode
in: query
required: false
schema:
type: string
enum:
- subway
- bus
- lirr
- metro-north
- name: route
in: query
required: false
schema:
minLength: 1
type: string
- name: stopId
in: query
required: false
schema:
minLength: 1
type: string
- name: includeRaw
in: query
required: false
schema:
type: boolean
responses:
'200':
description: Response for status 200
content:
application/json:
schema:
type: array
items:
type: object
required:
- id
- routes
- stops
- activePeriods
- source
properties:
id:
type: string
mode:
type: string
enum:
- subway
- bus
- lirr
- metro-north
routes:
type: array
items:
type: object
required:
- id
properties:
id:
type: string
shortName:
type: string
longName:
type: string
type:
type: number
color:
type: string
textColor:
type: string
stops:
type: array
items:
type: object
required:
- id
- name
properties:
id:
type: string
name:
type: string
displayName:
type: string
lat:
type: number
lon:
type: number
mode:
enum:
- subway
- bus
type: string
parentId:
type: string
header:
type: string
description:
type: string
url:
type: string
effect:
type: string
activePeriods:
type: array
items:
type: object
properties:
start:
type: string
end:
type: string
source:
type: string
raw: {}
components:
securitySchemes:
bearerAuth:
type: http
scheme: bearer
bearerFormat: API Key
apiKeyAuth:
type: apiKey
in: header
name: x-api-key
````