Historical Observing Metadata Repository

The Historical Observing Metadata Repository (HOMR) is NCDC's integrated station history database that provides in situ or land-based station metadata in support of NCDC research, reporting, data products, and web applications. HOMR tracks detailed information for a variety of weather stations throughout their lifespans, including identifiers, names, locations, observation times, reporting methods, and equipment modifications and siting. Station histories are most extensive for the National Weather Service (NWS) Cooperative Observing Program, and they include officially documented station changes that adhere to an NWS approval process. Use the search below to access these historical station details.

HOMR Web Service

HOMR provides a web service that you can use to get station metadata in JSON format. This page documents the URL formats used to get the data you want. All calls to the web service should be GET requests. The WADL for this web service can be found here:

http://www.ncdc.noaa.gov/homr/services/station?_wadl&_type=xml

All queries, if they find one or more stations, will return a JSON object with the property stationCollection, which contains a definitions section and a stations section. definitions contains the same information for each request: descriptive information about the fields that can be found in a station metadata entry. stations contains the list of stations that matched your search query. Each entry in the stations list has an ncdcStnId, and other properties such as names and location, depending on what information is available for that station.

Note that very broad searches - e.g. for an entire state or network - will take a very long time to return. Consider using the headersOnly=true argument (documented below) when making these kinds of requests.

Examples

The base URL for the web service is located here:
http://www.ncdc.noaa.gov/homr/services/station

If you know the unique NCDC Station ID of the station you are looking for, you can request it directly:
This will give you only the most recent values for each field. You can get the entire station history by adding date=all:
Other date options include single points in time and date ranges:
If you do not know exactly which station you are looking for, or you only know the qualified ID, you can use the search function with various parameters:

Available Query Parameters

qid
qid=[COOP|FAA|GHCND|ICAO|NCDCSTNID|NWSLI|TRANS|WBAN|WMO]?:[a-z0-9]*
Any fully qualified ID such as COOP:046742. When used with qidMod, can contain partial station ID's. Either the network or ID number may be omitted.

 

qidMod
qidMod=[is|starts|ends|contains]
Specifies how the ID portion of the qid parameter should be applied within the search. If a qid is passed but the qidMod parameter is not used, qidMod is assumed to be IS.

 

state
state=[A-Z]{2}
Two-letter code for US states, Canadian provinces, and other Island areas.

 

county
county=[A-Z]+
US county names, best used with a state identifier.

 

country
country=[A-Z]+
See here for a list of valid country names.

 

name
name=[0-9A-Z]+
Searches on any type of name we have for the station.

 

nameMod
nameMod=[is|starts|ends|contains]
Specifies how the name parameter should be applied within the search. If a name is passed but the nameMod parameter is not used, nameMod is assumed to be IS.

 

platform (aka network)
platform=[ASOS|USCRN|USHCN|NEXRAD|AL USRCRN|USRCRN|COOP]
Limit the search to stations of a certain platform/network type.

 

date
date=[YYYY-MM-DD|all]
Limits values to only those that occurred on a specific date. Alternatively, date=all will return all values for matched stations. If this field is omitted, the search will return only the most recent values for each field.

 

begindate/enddate
begindate=[YYYY-MM-DD]&enddate=[YYYY-MM-DD]
Limits values to only those that occurred within a date range.

 

headersOnly
headersOnly=true
Returns only minimal information for each station found (NCDC Station ID, Preferred Name, Station Begin Date, and Station End Date), but is much quicker than a full query. If you are performing a search that returns a large number of stations and intend to choose only one from that list to examine in detail, headersOnly may give you enough information to find the NCDC Station ID for the station that you actually want.

 

phrData
phrData=false
The HOMR web service now includes PHR (element-level) data when available, in an elements section. Because of how this data is structured, it can substantially increase the size of any result which includes it. If you don't need this data you can omit it by including phrData=false. If the parameter is not set, it will default to phrData=true.

 

definitions
definitions=false
The HOMR web service includes a list of definitions with every result. These are meant to serve as a reference for some of the more cryptic variable values, and are identical for every request. You can omit these from your result by setting definitions=false.