NOAA/NESDIS has made the eTRaP output available to users via anonymous ftp in three formats: McIDAS area file, text file and gif file. McIDAS users can easily display the data while users of the text format can develop the means to view the data on their own systems.
The text file will have the following format where east longitudes are positive and west longitudes are negative:
Line 1: BB##YYYY MMDDHH StormName
Line 2: GGLON SSLON LONL LONR GGLAT SSLAT LATL LATR
- BB - Basin
- AL - Atlantic
- EP - East Pacific
- CP - Central Pacific
- WP - Northwest Pacific
- NI - North Indian (includes Bay of Bengal and Arabian Sea)
- EI - Southeast Indian (between 90 deg E and 130 deg E)
- WI - Southwest Indian (west of 90 deg E)
- NT - Northern Territory (between 130E and 142 deg E)
- SW - Southwest Pacific (between 142E and 160 deg E)
- SE - Southeast Pacific (north of 25S and east of 160E)
- ## Storm number taken from forecast bulletin for systems in East Pacific, Atlantic and Central Pacific; otherwise 99 in all other ocean basins
- YYYY - The calendar year the storm occurred
- MMDDHH - Current month day and forecast hour
- StormName - The name of the storm
Line 3-7: LON LAT TIME
- GGLON - The number of grid points in the longitudinal direction
- SSLON - The resolution (in degrees) of the rainfall grid in the longitudinal direction
- LONL - The longitude of the lower left hand corner of the rainfall grid
- LONR - The longitude of the upper right hand corner of the rainfall grid
- GGLAT - The number of grid points in the latitudinal direction
- SSLAT - The resolution (in degrees) of the rainfall grid in the latitudinal direction
- LATL - The latitude of the lower left hand corner of the rainfall grid
- LATR - The latitude of the upper right hand corner of the rainfall grid
- Since the eTRaP is generated from multiple forecasts, the LON and LAT will contain a null set (i.e., LON=999.99 on each line; LAT=99.99 on each line).
Line 8-n: Varies depending upon whether file is for QPF or probability
Line 8-n for QPF: LON LAT RAIN
Line 8-n for Probability: LON LAT PROBABILITY
- LON/LAT - is the position in longitude/latitude of the rainfall calculated
- RAIN - amount of rainfall in inches
LON/LAT is the position in longitude/latitude of the probability calculated
PROBABILITY – probability expressed as an integer from 0-100Note: In both the QPF and probability files, line 8 through line n contains a sorted list of longitude/latitude points. The longitude/latitude points cover a square area and are listed from the lower left corner of the rainfall grid to the top right corner.
How to access files :
Sample text files, McIDAS area files and gif files can be accessed through the following site: ftp://satepsanone.nesdis.noaa.gov/TRAP/ETRAP/example/
By way of example, file names have the following form:
.....2009BIJLI.p100.04161200.00.GIF
.....2009BIJLI.p100.04161200.00.Z
.....2009BIJLI.p100.04161200.00.TXT.Z
With the exception of the gif image, the files are compressed as indicated by the .Z at the end of the file names. Text files are indicated by .TXT. Files not containing the .TXT are McIDAS area files. PC users can use WinZip to uncompress/unzip the files, which will launch automatically after clicking on a compressed file. In Linux/Unix, in the directory where the file is located, type uncompress <file_name> as in the following example:
uncompress 2009JADE.p100.04110000.00.TXT.Z
File names can be interpreted as follows:
Year Product Type Time Period | | | 2009JADE.p100.04110000.00.TXT.Z | | Storm Name MMDDHHMM (i.e., 2 digit month, 2 digit day, 2 digit hr, 2 digit minute)
The storm name could be a name as in the example above or an alphanumeric (e.g. 28S) if the system is only of tropical depression intensity. The time the eTRaP is valid is of the form MMDDHHMM. The product types are as follows:
The time periods for both probabilistic forecasts and rainfall amounts will be:
Contact Information: |
||
You are Here: http://www.ssd.noaa.gov/PS/TROP/etrap-expl.html
|