# SWDI vignette

#### Scott Chamberlain

#### 2019-11-20

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`SWDI` is the Severe Weather Data Inventory. SWDI is an (quoting)

> integrated database of severe weather records for the United States. The records in SWDI come from a variety of sources in the NCDC archive. SWDI provides the ability to search through all of these data to find records covering a particular time period and geographic region, and to download the results of your search in a variety of formats. The formats currently supported are Shapefile (for GIS), KMZ (for Google Earth), CSV (comma-separated), and XML.

Data available in SWDI are:

- Storm Cells from NEXRAD (Level-III Storm Structure Product)
- Hail Signatures from NEXRAD (Level-III Hail Product)
- Mesocyclone Signatures from NEXRAD (Level-III Meso Product)
- Digital Mesocyclone Detection Algorithm from NEXRAD (Level-III MDA Product)
- Tornado Signatures from NEXRAD (Level-III TVS Product)
- Preliminary Local Storm Reports from the NOAA National Weather Service
- Lightning Strikes from Vaisala NLDN

Find out more about SWDI at http://www.ncdc.noaa.gov/swdi/#Intro.

## Load rnoaa

    library('rnoaa')

## Search for nx3tvs data from 5 May 2006 to 6 May 2006

    swdi(dataset='nx3tvs', startdate='20060505', enddate='20060506')

## Use an id

    out <- swdi(dataset='warn', startdate='20060506', enddate='20060507', id=533623)
    list(out$meta, head(out$data), head(out$shape))

## Get all ‘plsr’ within the bounding box (-91,30,-90,31)

    swdi(dataset='plsr', startdate='20060505', enddate='20060510', bbox=c(-91,30,-90,31))

## Get all ‘nx3tvs’ within the tile -102.1/32.6 (-102.15,32.55,-102.25,32.65)

    swdi(dataset='nx3tvs', startdate='20060506', enddate='20060507', tile=c(-102.12,32.62))

## Counts

Notes:

- stat=‘count’ will only return metadata, nothing in the data or shape slots
- stat=‘tilesum:…’ returns counts in the data slot for each date for that tile, and shape data
- Get number of ‘nx3tvs’ within 15 miles of latitude = 32.7 and longitude = -102.0

Get daily count nx3tvs features on .1 degree grid centered at `latitude = 32.7` and `longitude = -102.0`

    swdi(dataset='nx3tvs', startdate='20060505', enddate='20090516', stat='tilesum:-102.0,32.7')

## Get data in different formats

### CSV format

    head(swdi(dataset='nx3tvs', startdate='20060505', enddate='20060506', format='csv')$data)

### SHP format

    swdi(dataset='nx3tvs', startdate='20060505', enddate='20060506', format='shp', filepath='myfile')

### KMZ format

    swdi(dataset='nx3tvs', startdate='20060505', enddate='20060506', format='kmz', radius=15, filepath='myfile.kmz')