National Weather Service United States Department of Commerce

 

Shapefile Type: Polygon

Data source: Derived from Census TIGER 2000

Naming convention: c_ddmmyy  where ddmmyy = day-month-year

NWS Specifications: NWSM 10-507

Description: Counties of the U.S used by NWS to issue county based forecasts and warnings.

Additional Info: This county data set differs from other county datasets in that certain counties although having the same FIPS code comprise of more than one polygon, each polygon having a different name in the countyname field. This was done in order to allow the forecasters at the sites to issue warnings to these separate parts of the counties.  In addition a number of counties along various waterways contain two records with the same FIPS code and name.  This is to allow NWS forecasters to visualize these inlets but at the same time to issue a land based product (opposed to a marine based product) for those entities.

Time Zones: Time zone assignments use the following codes:

 V   Atlantic Standard
 E   Eastern Standard
 C   Central Standard
 M   Mountain Standard (m = daylight time not observed)
 P   Pacific Standard
 A   Alaska Standard
 H   Hawaii-Aleutian Standard
 G   Guam & Marianas
 S   Samoa Standard

Two letters appear for the nine (9) counties (10 records total) which are divided by a time zone boundary, which are located in the states of FL (Gulf), ID (Idaho), ND (McKenzie, Dunn, and Sioux), NE (Cherry), OR (Malheur), SD (Stanley), and TX (Culberson).

FE_AREA abbreviations: The field FE_AREA is used internally to allow warnings to specify the portion of the state in which the county exists.

 nn northern         ss southern         ea east
 ee eastern          ww western          er east central upper
 cc central          pa panhandle        eu eastern upper 
 ne north eastern    se south eastern    nr north central upper
 nw north western    sw south western    sr south central upper  
 nc north central    sc south central    wu western upper
 ec east central     wc west central     so south
 mi middle           pd piedmont
 bb big bend         up upstate

 

Description Valid date Data Download # Records MD5SUM Documentation
U.S. Counties 2 October 2018 c_02oc18.zip 3332 53A58C4C883DF90313C6712151059FA8 Change History Metadata

 

Shapefile Attributes:

Field Name Ttype width,dec Description
STATE character 2 [ss] State abbreviation (standard US Postal)
CWA character 9 [wfowfowfo] County Warning Area (WFO Identifier), see NWS Comments
COUNTYNAME character 24 County name
FIPS character 5 [ssccc] FIPS Code
TIME_ZONE character 2 [tt] Time zone assignment (DOT), see comments
FE_AREA character 2 [aa] Feature Area (location in STATE) {nc,ne, etc., see comments}
LON numeric 10,5 Longitude of Centroid [decimal degrees]
LAT numeric 9,5 Latitude of Centroid [decimal degrees]