Counties and county equivalents of the United States including Alaska, Hawaii, American Samoa, Guam, The Marianas Islands, Midway, Puerto Rico and the U.S. Virgin Islands.
Purpose:
Used by the National Weather Service (NWS) for issuing wactches and warnings of severe weather.
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.2.2.1350
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
All attributes were verifed by the individual Weather Forecast Offices (WFOs) and QC passes by personell at NWS Headquarters. WFOs have input into the fe_area field, the Office of Climate, Water, and Weather Services have input into the CWA field.
The shoreline boundaries of the data is dependent on the shoreline edges of rivers and bays as delineated on a USGS DLG The edges or borders of the boundary might change as the natural land changes and WFOs request changes.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The data was created from USGS 1:2,000,000 DLG counties and assumed to have the same horizintal accuracy of that data set.
Source_Contribution: Original boundaries and FIPS codes
Process_Step:
Process_Description:
A county shapefile was generated from the USGS DLG CD-ROM and reprojected into a NAD83 dataset. The counties in the shapefile were split as appropriate to create Public Forecast Zones and all county boundaries were retained. This shapefile is retained as an offline private shape file called a "master" file and it contains unique polygons of county, cwa and forecast zone data. All changes to counties, zones, CWAs are first made to this "master" file.
To create the counties data set, a copy of the master file is created and renamed and the polygons are "dissolved" on the FIPS code field and the lat/lon of the centroids are calculated.
Process_Date: 20020808
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Ira Graffman
Contact_Organization: National Weather Service/OST
Updated Akaska county boundaries were subsetted into a separate shapefile. Old Alaska boundaries were deleted from main offline master shapefile and the two shapefiles were merged.
The information depicted in this GIS layer is the result of digital analyses performed on a database consisting of information from a variety of governmental and other credible sources. The accuracy of the information presented is limited to the collective accuracy of the database on the date of the analysis. The information is believed accurate and reasonable efforts have been made to ensure the accuracy of the data. However, the National Weather Service/OST expressly disclaims responsibility for damages or liability that may arise from use of this data. This product is the property of the National Weather Service/OST and its use is thereby restricted.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: ESRI Shapefile
Transfer_Size: 13.970
Digital_Transfer_Option:
Offline_Option:
Fees: None
Metadata_Reference_Information:
Metadata_Date: 20071010
Metadata_Review_Date: 20020813
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: National Weather Service/OST
