Hazardous Air Quality (Dissolved Polygons)

This nowCOAST™ time-enabled map service provides maps depicting the geographic coverage of the latest NOAA/National Weather Service (NWS) WATCHES, WARNINGS, ADVISORIES, and STATEMENTS for long-duration hazardous weather, marine weather, hydrological, oceanographic, wildfire, air quality, and ecological conditions which may or are presently affecting inland, coastal, and maritime areas. A few examples include Gale Watch, Gale Warning, High Surf Advisory, High Wind Watch, Areal Flood Warning, Coastal Flood Watch, Winter Storm Warning, Wind Chill Advisory, Frost Advisory, Tropical Storm Watch, Red Flag Warning, Air Stagnation Warning, and Beach Hazards Statement. (A complete list is given in the Background Information section below.) The coverage areas of these products are usually defined by county or sub-county boundaries. The colors used to identify the different watches, advisories, warnings, and statements are the same colors used by the NWS on their map at weather.gov. The NWS products for long-duration hazardous conditions are updated in the nowCOAST map service approximately every 10 minutes. For more detailed information about the update schedule, please see: http://new.nowcoast.noaa.gov/help/#section=updateschedule.

The coverage areas of these products are usually defined by county or sub-county boundaries, but for simplicity and performance reasons, adjacent WWAs of the same type, issuance, and expiration are depicted in this service as unified (merged/dissolved) polygons in the layers indicated with the suffix "(Dissolved Polygons)". However, a set of equivalent layers containing the original individual zone geometries are also included for querying purposes, and are indicated with the suffix "(Zone Polygons)". Corresponding zone polygon and dissolved polygon layers are matched together in group layers for each WWA category. The zone polygon layers are included in this service only to support query/identify operations (e.g., in order to retrieve the original zone geometry or other attributes such as a URL to the warning text bulletin) and thus will not be drawn when included in a normal map image request. Thus, the dissolved polygon layers should be used when requesting a map image (e.g. WMS GetMap or ArcGIS REST export operations), while the zone polygon layers should be used when performing a query (e.g. WMS GetFeatureInfo or ArcGIS REST query or identify operations).

The colors used to identify the different watches, advisories, warnings, and statements are the same colors used by the NWS on their map at http://www.weather.gov. The NWS products for long-duration hazardous conditions are updated in the nowCOAST™ map service approximately every 10 minutes. For more detailed information about layer update frequency and timing, please reference the
nowCOAST™ Dataset Update Schedule.

Background Information

NWS watches depict the geographic areas where the risk of hazardous weather or hydrologic events has increased significantly, but their occurrence, location, and/or timing is still uncertain. A warning depicts where a hazardous weather or hydrologic event is occurring, is imminent, or has a very high probability of occurring. A warning is used for conditions posing a threat to life or property. Advisories indicate where special weather conditions are occurring, imminent, or have a very high probability of occurring but are less serious than a warning. They are for events that may cause significant inconvenience, and if caution is not exercised, could lead to situations that may threaten life and/or property. Statements usually contain updated information on a warning and are used to let the public know when a warning is no longer in effect. NWS issues over 75 different types of watches, warnings, and advisories (WWAs). WWAs are issued by the NWS regional Weather Forecast Offices (WFOs) and also the NWS Ocean Prediction Center, National Hurricane Center, Central Pacific Hurricane Center, and Storm Prediction Center.

The NWS WWAs are organized on the nowCOAST™ map viewer and within this map service by hazardous condition/threat layer groups and then by the geographic area (i.e. coastal & inland, immediate coast or maritime) for which the WWA product is targeted. This was done to allow users to select WWAs for hazardous conditions that are important to their operations or activities.

Please note that the Tropical Storm and Hurricane Warnings are provided in both the High Wind Hazards: Maritime Areas and Coastal & Inland Areas layer groups and the Flooding Hazards: Coastal Areas layer group. These warnings are included in the Flooding Hazards/Coastal Areas layer group because the NWS uses those warnings to inform the public that tropical storm or hurricane winds may be accompanied by significant coastal flooding but below the thresholds required for the issuance of a storm surge warning. In addition, a tropical storm or hurricane warning may remain in effect when dangerously high water or a combination of dangerously high water and waves continue, even though the winds may be less than hurricane or tropical storm force. The NWS does not issue a Coastal Flood Warning or Advisory when a tropical storm or hurricane warning is in effect; however that does not mean that there is not a significant coastal flooding threat.

High Wind Hazards (Associated with Non-Tropical & Tropical Cyclones)


    Maritime Areas

      Brisk Wind Advisory
      Small Craft Advisory
      Small Craft Advisory for Winds
      Gale Watch
      Gale Warning
      Storm Watch
      Storm Warning
      Hurricane Force Wind Watch
      Hurricane Force Wind Warning
      Tropical Storm Watch
      Tropical Storm Warning
      Hurricane Watch
      Hurricane Warning



    Coastal & Inland Areas

      High Wind Watch
      Wind Advisory
      Lake Wind Advisory
      High Wind Warning
      Tropical Storm Watch
      Tropical Storm Warning
      Hurricane Watch
      Hurricane Warning





Hazardous Seas, Surf, and Beach Conditions


    Maritime Areas

      Small Craft Advisory for Hazardous Seas
      Small Craft Advisory for Rough Bar
      Hazardous Seas Watch
      Hazardous Seas Warning



    Immediate Coast

      Beach Hazards Statement
      High Surf Advisory
      High Surf Warning 
      Low Water Advisory
      Rip Current Statement





Flooding Hazards


    Coastal Areas

      Coastal Flood Statement
      Coastal Flood Watch
      Coastal Flood Advisory
      Coastal Flood Warning
      Lakeshore Flood Watch
      Lakeshore Flood Advisory
      Lakeshore Flood Warning
      Lakeshore Flood Statement
      Storm Surge Watch
      Storm Surge Warning
      Tsunami Watch
      Tsunami Warning
      Tropical Storm Warning
      Hurricane Warning



    Inland Areas

      Flood Watch (Point) (also called River Flood Watch)
      Flood Watch (Areal)
      Flood Advisory (Point) (also called River Flood Advisory)
      Flood Advisory (Areal)
      Flood Warning (Point) (also called River Flood Warning)
      Flood Warning (Areal)
      Hydrologic Outlook
      Hydrologic Statement





Reduced Visibility Hazards


    Maritime Areas

      Dense Fog Advisory



    Coastal & Inland Areas

      Ashfall Advisory
      Ashfall Warning
      Blowing Dust Advisory
      Blowing Dust Warning
      Dense Fog Advisory
      Dense Smoke Advisory





Freezing Spray Hazards

  Maritime Areas

      Heavy Freezing Spray Watch
      Freezing Spray Advisory
      Heavy Freezing Spray Advisory





Snow, Sleet, Freezing Rain, and Freezing Fog Hazards


    Coastal & Inland Areas

      Blizzard Watch
      Blizzard Warning
      Freezing Fog Advisory
      Freezing Rain Advisory
      Ice Storm Warning
      Lake-Effect Snow Watch
      Lake-Effect Snow Advisory
      Lake-Effect Snow Warning
      Winter Storm Watch
      Winter Weather Advisory
      Winter Storm Warning





Cold and Heat Hazards


    Coastal & Inland Areas

      Excessive Cold Watch
      Excessive Cold Warning
      Excessive Heat Watch
      Heat Advisory
      Excessive Heat Warning
      Frost Advisory
      Freeze Watch
      Freeze Warning
      Wind Chill Advisory
      Wind Chill Warning





Critical Wildfire Conditions


    Coastal & Inland Areas

      Fire Weather Watch
      Red Flag Warning





Unhealthy Air Quality


    Coastal & Inland Areas

      Air Stagnation Advisory
      Air Quality Alerts from states are NOT available

For descriptions of individual NWS watches, warnings, and advisories please see Section 2 of the NWS Reference Guide available at http://www.nws.noaa.gov/om/guide/Section2.pdf.

Time Information

This map service is time-enabled, meaning that each individual layer contains time-varying data and can be utilized by clients capable of making map requests that include a time component.

In addition to ArcGIS Server REST access, time-enabled OGC WMS 1.3.0 access is also provided by this service.

This particular service can be queried with or without the use of a time component. If the time parameter is specified in a request, the data or imagery most relevant to the provided time value, if any, will be returned. If the time parameter is not specified in a request, the latest data or imagery valid for the present system time will be returned to the client. If the time parameter is not specified and no data or imagery is available for the present time, no data will be returned.

This service is configured with time coverage support, meaning that the service will always return the most relevant available data, if any, to the specified time value. For example, if the service contains data valid today at 12:00 and 12:10 UTC, but a map request specifies a time value of today at 12:07 UTC, the data valid at 12:10 UTC will be returned to the user. This behavior allows more flexibility for users, especially when displaying multiple time-enabled layers together despite slight differences in temporal resolution or update frequency.

When interacting with this time-enabled service, only a single instantaneous time value should be specified in each request. If instead a time range is specified in a request (i.e. separate start time and end time values are given), the data returned may be different than what was intended.

Care must be taken to ensure the time value specified in each request falls within the current time coverage of the service. Because this service is frequently updated as new data becomes available, the user must periodically determine the service's time extent. However, due to software limitations, the time extent of the service and map layers as advertised by ArcGIS Server does not always provide the most up-to-date start and end times of available data. Instead, users have three options for determining the latest time extent of the service:

    Issue a returnUpdates=true request (ArcGIS REST protocol only)
    for an individual layer or for the service itself, which will return
    the current start and end times of available data, in epoch time format
    (milliseconds since 00:00 January 1, 1970). To see an example, click on
    the "Return Updates" link at the bottom of the REST Service page under
    "Supported Operations". Refer to the
    ArcGIS REST API Map Service Documentation
    for more information.


    Issue an Identify (ArcGIS REST) or GetFeatureInfo (WMS) request against
    the proper layer corresponding with the target dataset. For raster
    data, this would be the "Image Footprints with Time Attributes" layer
    in the same group as the target "Image" layer being displayed. For
    vector (point, line, or polygon) data, the target layer can be queried
    directly. In either case, the attributes returned for the matching
    raster(s) or vector feature(s) will include the following:


            validtime: Valid timestamp.


            starttime: Display start time.


            endtime: Display end time.


            reftime: Reference time (sometimes referred to as
            issuance time, cycle time, or initialization time).


            projmins: Number of minutes from reference time to valid
            time.


            desigreftime: Designated reference time; used as a
            common reference time for all items when individual reference
            times do not match.


            desigprojmins: Number of minutes from designated
            reference time to valid time.




    Query the nowCOAST™ LayerInfo web service, which has been created to
    provide additional information about each data layer in a service,
    including a list of all available "time stops" (i.e. "valid times"),
    individual timestamps, or the valid time of a layer's latest available
    data (i.e. "Product Time"). For more information about the LayerInfo
    web service, including examples of various types of requests, refer to
    the 
    nowCOAST™ LayerInfo Help Documentation

References

NWS, 2006: NWS Instructions 10-313, WFO Severe Weather Products Specification, NWS, Silver Spring, MD. NWS, 2007: NWS Instructions 10-320, Coastal/Lakeshore Hazard Services, NWS, Silver Spring, MD. NWS, 2007: NWS Instructions 10-922, Weather Forecast Office Hydrologic Products Specification, NWS, Silver Spring, MD. NWS, 2008: NWS Instructions 10-301, Marine and Coastal Services Abbreviations and Definitions, NWS, Silver Spring, MD. NWS, 2010: NWS Instructions 10-519, WFO Air Quality Products Specification, NWS, Silver Spring, MD. NWS, 2011: NWS Products and Services Reference Guidebook, NWS/Office of Climate, Water, and Weather Services, Silver Spring, MD. NWS, 2012: NWS Policy Directive 10-3, Marine and Coastal Weather Services, NWS, Silver Spring, MD. NWS, 2012: NWS Instructions 10-701, Tsunami Warning Center Operations, NWS, Silver Spring, MD. NWS, 2013: NWS Instructions 10-601, Tropical Cyclone Products, NWS, Silver Spring, MD. NWS, 2012: NWS Instructions 10-701, Tsunami Warning Center Operations, NWS, Silver Spring, MD.

NWS Instructions and other directives are available at http://www.nws.noaa.gov/directives/.

Data and Resources

Additional Info

Field Value
Source https://gis-calema.opendata.arcgis.com/datasets/e9a668d8d3be44f8a42b48db7a2b353b_41
Last Updated June 23, 2021, 21:15 (UTC)
Created June 23, 2021, 02:46 (UTC)
GUID https://gis-calema.opendata.arcgis.com/datasets/e9a668d8d3be44f8a42b48db7a2b353b_41
Language
dcat_issued 2019-08-30T23:14:18.000Z
dcat_modified 2019-10-10T21:13:55.000Z
dcat_publisher_name CA Governor's Office of Emergency Services
spatial {"type": "Polygon", "coordinates": [[[-180.0, -89.0], [-180.0, 89.0], [180.0, 89.0], [180.0, -89.0], [-180.0, -89.0]]]}