I'm working on a project which takes the NOAA NWS alerts and places them onto a Google Map. https://alerts.weather.gov/cap/us.php?x=0

Most alerts use the FIPS or UGC codes. I don't think I need the extreme level of detail that UGC offers, so I'm going with FIPS.

I downloaded the shapefile of NOAA's US Counties (http://www.nws.noaa.gov/geodata/catalog/county/html/county.htm) which has the FIPS polygons defined. Opened it in OpenJUMP and exported a CSV. The CSV has polygons that have 15 decimal places.

1 FIPS polygon can be upwards of 1,000,000 characters. Considering the NWS alerts define multiple FIPS, loading such data onto a map would take forever - especially on mobile phones. I've tried truncating the decimals to 2, but the amount of points is still quite large.

The end goal is to create a geoJSON conversion of the NWS alerts that will show the alerts on the map. I'm trying to avoid a 150mb geoJSON file due to the amount of polygon coordinates.

Is there a simplified version (much less points, softer "edges") of the FIPS polygons I could use?

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