Severe Weather Alerts API Format

The WxData™ Severe Weather Alerts API provides direct access to real-time active and historical U.S. severe weather alerts beginning June 2018. The API returns all provided severe weather alert type and associated elements or only those that meet your needs.

If you have an existing account using the API Explorer is recommended to build API calls. Additionally, securely passing "key" and "secret" in the http header is supported. Curl example represented below:

curl "" \
-H "key: [provided-apikey]" \
-H "secret: [provided-secretkey]"

In your API call you can filter on these elements:

  • Location
  • Severe weather event type (EG Tornado Warning, Flood Warning, ...)
  • Active or expired (historical)
  • Date range
  • Magnitude confidence
  • Magnitude range

HTTP Methods

API supports GET

Base URL



Request Parameters

The following parameters may be used:

Parameter Description Required Values
version Version control Required 1.0
format Return data format Required "xml" or "json"
key User API access key Required As provided by WxData™
secret Secret key (do not share) Required As provided by WxData™
status Switch to locate active or expired alerts Required active or expired
location 1) City filter, also requires state, 2) Two character state abbreviation, 3) State abbreviation and county code, 4) State abbreviation and zone code, 5) Nationwide, or 6) Latitude longitude point Optional
  • City Filter Example Values:
  • Boston,MA
  • New+York+City,NY

  • State Example Values:

  • State abbreviation and county code:
  • MA+C015

  • State abbreviation and zone code:
  • MI+Z049

  • Nationwide Example value:
  • US

  • Latitude longitude Point:
  • 40.7829N+73.9654W (NYC)

date Start date range (YYYY-MM-DDTHH:MM:SS) Required
  • Example:
  • date=2011-06-11T16:00:00 (June 6, 2011)

  • Latest:
  • date=0000-00-00T00:00:00
  • enddate=0000-00-00T00:00:00
enddate End date range (YYYY-MM-DDTHH:MM:SS) Required
  • Examples:
  • date=2017-06-30T13:00:00 (June 30, 2017)

  • Latest:
  • date=0000-00-00T00:00:00
  • enddate=0000-00-00T00:00:00
event Event type (leave blank for all events) Optional
  • Severe Weather
  • Tornado+Warning
  • Tornado+Watch
  • Severe+Thunderstorm+Warning
  • Severe+Thunderstorm+Watch
  • Severe+Weather+Statement

  • Flooding
  • Flash+Flood+Warning
  • Flash+Flood+Statement
  • Flash+Flood+Watch
  • Flood+Warning
  • Flood+Watch
  • Flood+Advisory
  • Flood+Statement
  • Lakeshore+Flood+Warning
  • Lakeshore+Flood+Watch
  • Lakeshore+Flood+Advisory
  • Lakeshore+Flood+Statement

  • Winter Alerts
  • Winter+Storm+Warning
  • Winter+Storm+Watch
  • Blizzard+Warning
  • Blizzard+Watch
  • Winter+Weather+Advisory
  • Snow+Squall+Warning
  • Lake+Effect+Snow+Warning
  • Lake+Effect+Snow+Watch
  • Lake+Effect+Snow+Advisory
  • Freeze+Warning
  • Freeze+Watch
  • Freezing+Rain+Advisory
  • Ice+Storm+Warning
  • Avalanche+Warning
  • Avalanche+Watch

  • Non-Precipitation Alerts
  • Frost+Advisory
  • Wind+Chill+Warning
  • Wind+Chill+Watch
  • Wind+Chill+Advisory
  • Extreme+Cold+Warning
  • Hard+Freeze+Warning
  • Hard+Freeze+Watch
  • Excessive+Heat+Warning
  • Excessive+Heat+Watch
  • Heat+Advisory
  • Extreme+Wind+Warning
  • High+Wind+Warning
  • High+Wind+Watch
  • Wind+Advisory
  • Brisk+Wind+Advisory
  • Dense+Fog+Advisory
  • Lake+Wind+Advisory
  • Air+Stagnation+Advisory
  • Air+Quality+Alert
  • Blowing+Dust+Advisory
  • Dust+Storm+Warning
  • Dense+Smoke+Advisory
  • Ashfall+Advisory

  • Fire Weather Alerts
  • Fire+Warning
  • Fire+Weather+Watch
  • Red+Flag+Warning
  • Extreme+Fire+Danger

  • Tropical Alerts
  • Hurricane+Warning
  • Hurricane+Watch
  • Hurricane+Local+Statement
  • Tropical+Storm+Warning
  • Tropical+Storm+Watch
  • Hurricane+Force+Wind+Warning
  • Hurricane+Force+Wind+Watch
  • Storm+Surge+Warning
  • Storm+Surge+Watch

  • Coastal Alerts
  • Tsunami+Warning
  • Tsunami+Watch
  • Coastal+Flood+Warning
  • Coastal+Flood+Watch
  • Coastal+Flood+Advisory
  • Coastal+Flood+Statement
  • Beach+Hazards+Statement
  • High+Surf+Advisory
  • Rip+Current+Statement

  • Civil Emergency Alerts
  • 911+Telephone+Outage
  • 911+Telephone+Outage+Emergency
  • Law+Enforcement+Warning
  • Child+Abduction+Emergency
  • Shelter+in=Place+Warning
  • Civil+Emergency+Message

Return Elements: Information About The Returned Weather Observation Data

Value Description Type
id iAlert record ID int
status active or expired alert text
event Weather alert type text
headline Alert summary headline text
description Detail alerts text text
effective Weather event start time YYYY-MM-DDTHH:MM:SS
expires Weather event end time YYYY-MM-DDTHH:MM:SS


County list of locations under alert text


lat/lon if provided text


County codes under alert text


Specific Area Message Encoding text


Valid event time code text

XML Sample Output

<response xmlns:xsd="" xmlns:xsi="" version="1.2" xsi:noNamespaceSchemaLocation=""> <time_taken_ms>191</time_taken_ms> <errors/> <warnings/> <data num_results="2"> <record> <id>l12345</id> <status>active</status> <event>Heat Advisory</event> <headline Heat Advisory issued July 26 at 4:19AM CDT until July 27 at 7:00PM CDT by NWS </headline> <description>TBD</description> <effective>2017-07-26T04:19:00-05:00</effective> <expires>2017-07-27T19:00:00-05:00</expires> <areaDesc>Ashley; Chicot</areaDesc> <geo_coordinates></geo_coordinates> <geocode>FIPS6</geocode> <same_code>005003 005017</same_code> <vtec>O.NEW.KJAN.HT.Y.0005.170726T1600Z-170728T0000Z/</vtec> </record> </data> </response>

JSON Sample Output

{ "response":{ "data_source": "(active) Land Based Severe Weather Alerts", "version": "2 of 2 records returned", "time_taken_ms":"060", "warning":"", "data":{ "num_results": "2 of 2 records returned", "record":[ { "id":"l2544", "status":"active", "event":"Flash Flood Watch", "headline":"Flash Flood Watch issued June 12 at 1:15PM CDT expiring June 13 at 5:00AM CDT", "description":"The National Weather Service in Paducah has expanded the * Flash Flood Watch to include portions of southern Illinois and southwest Indiana, including the following areas, in southern Illinois, White. In southwest Indiana, Posey, Spencer, Vanderburgh, and Warrick. * Through late tonight * Very heavy rain over the past few days has saturated the ground in parts of the watch area. Around 10 inches of rain has fallen in Hazleton Indiana. Any additional heavy rainfall would produce renewed flash flooding. * Flood prone and low lying areas will likely become inundated if thunderstorms with torrential rain occur.", "effective":"2018-06-12 13:15:00", "expires":"2018-06-13 05:00:00", "areaDesc":"Posey; Spencer; Warrick; Vanderburgh; White", "geo_coordinates":"", "geocode":"INZ085-INZ088-INZ087-INZ086-ILZ083", "same_code":"018129-018147-018173-018163-017193", "vtec":"/O.EXB.KPAH.FF.A.0003.000000T0000Z-180613T1000Z/" }, { "id":"l2627", "status":"active", "event":"Flash Flood Watch", "headline":"Flash Flood Watch issued June 12 at 2:59PM CDT expiring June 13 at 1:00AM CDT", "description":"The National Weather Service in Lincoln has issued a * Flash Flood Watch for a portion of southeast Illinois, including the following areas, Clay, Crawford, Effingham, Jasper, Lawrence, and Richland. * Until 1 AM CDT Wednesday * Between five to nine inches of rain has fallen over portions of southeast Illinois over the past 48 hours. Another round of a couple inches of rain is possible late this afternoon through tonight. This additional rainfall on the saturated ground may lead to flash flooding. * Flash flooding will be possible in streams and low spots across the watch area.", "effective":"2018-06-12 14:59:00", "expires":"2018-06-12 21:00:00", "areaDesc":"Effingham; Richland; Clay; Jasper; Lawrence; Crawford", "geo_coordinates":"", "geocode":"ILZ066-ILZ072-ILZ071-ILZ067-ILZ073-ILZ068", "same_code":"017049-017159-017025-017079-017101-017033", "vtec":"/O.NEW.KILX.FF.A.0003.180612T2200Z-180613T0600Z/" } ] } } }

Our weather API is currently used worldwide by users to feed their apps, services, and mission with reliable weather data.

If you have any queries, then please contact us. Pricing