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Severe Thunderstorms and Heavy Rain in the Southern Plains; Fire Weather Threat in the Southwest U.S.

Thunderstorms, some severe, may produce heavy to excessive rainfall and isolated flooding over portions of the Southern Plains today and Saturday. Dry conditions, combined with gusty winds and low relative humidities will continue to support an elevated to critical fire weather threat in the Desert Southwest into to early next week. Read More >

 

Gateway File Services SSM/I Satellite Product Files

Introduction

The U.S. National Weather Service provides anonymous FTP access to files containing SSM/I imagery products generated from polar obit satellites with id's of F13, F14, or F15.   The files do not have the standard WMO abbreviated heading enveloping the products. The most current set of products are kept on the server. All archive sources must be through NESDIS's Satellite Active Archive.   The server internal structure for subdirectory names and file names are taken from the documented OSO File Name Standards. The naming conventions for the subdirectories and files are described in the document titled: File and Directory Name Standards.   The data is available at the NWS Telecommunication Gateway on the server https://tgftp.ncep.noaa.gov/ via anonymous FTP.

Availability

The data can be obtained through standard FTP. By checking the date/time of the files on the server you will be able to maintain a user's stat file on when the next set of products to FTP are available. There are 3 product types for each satellite provided on the server.   The data will be available, as soon as possible, after delivery by the NESDIS "CEMSCS" servers. These products are created on DoD servers and must be delivered to NESDIS before becoming available on the Gateway servers.

Data types available

TDR

Temperature Data Records (TDRs) contain calibrated and earth-located data prior to irreversible antenna pattern correction. The temperature data represents microwave energy levels measured by the seven channels of the radiometer instrument. The energy levels are expressed as an equivalent black body temperature (antenna temperature).

SDR

Sensor data records (SDRs) are time-tagged, earth-located and calibrated antenna-pattern-corrected brightness temperatures for all seven SSM/I channels.

EDR

Environmental Data Records (EDRs) are time-tagged earth-located meteorological and oceanographic parameters produced from the SSM/I SDRs. The derived parameters include Cloud Water Vapor, Cloud Liquid Water, Rain Rate, Sea Ice Concentration, Sea Ice Age, Sea Ice Edge, Soil Moisture, Surface Wind, Water Vapor over oceans (precipitous water), Surface Temperature, Snow Water Content, Cloud Amount, and EDR Surface Type.

Directory and File Descriptions

See "Directory and File Naming Standards" for information about directory and file name formats and strurture.

To be used for FTP access
Directory Name Contents
SL.us008001/ Data root - for NWS Telecommunication Gateway Server (top directory)
    DF.of/ Data in NESDIS coded form either ASCII or Binary depending on product
        DC.sfsat/ Data category: Surface Data - Satellite
            DS.ssmie/ Data Subcategory: SSM/I Environmental Data Records (EDR)
                SI.f13/ Data site: Satellite identification number for polar orbit satellite
                    DD.yyyymmdd/ Data Date: year, month, and day,
                       tp.hhnn-hhnnn_ar.nnnnnnn Filename Data Time: Beginning-Ending Time and Area of Data: Satellite orbit number
                SI.f14/ Data site: Satellite identification number for polar orbit satellite
                    DD.yyyymmdd/ Data Date: year, month, and day,
                       tp.hhnn-hhnnn_ar.nnnnnnn Filename Data Time: Beginning-Ending Time and Area of Data: Satellite orbit number
                SI.f15/ Data site: Satellite identification number for polar orbit satellite
                    DD.yyyymmdd/ Data Date: year, month, and day,
                       tp.hhnn-hhnnn_ar.nnnnnnn Filename Data Time: Beginning-Ending Time and Area of Data: Satellite orbit number
            DS.ssmis/ Data Subcategory: SSM/I Sensor Data Records (SDR)
                SI.f13/ Data site: Satellite identification number for polar orbit satellite
                    DD.yyyymmdd/ Data Date: year, month, and day,
                       tp.hhnn-hhnnn_ar.nnnnnnn Filename Data Time: Beginning-Ending Time and Area of Data: Satellite orbit number
                SI.f14/ Data site: Satellite identification number for polar orbit satellite
                    DD.yyyymmdd/ Data Date: year, month, and day,
                       TP.hhnn-hhnnn_ar.nnnnnnn Filename Data Time: Beginning-Ending Time and Area of Data: Satellite orbit number
                SI.f15/ Data site: Satellite identification number for polar orbit satellite
                    DD.yyyymmdd/ Data Date: year, month, and day,
                       tp.hhnn-hhnnn_ar.nnnnnnn Filename Data Time: Beginning-Ending Time and Area of Data: Satellite orbit number
            DS.ssmit/ Data Subcategory: SSM/I Temperature Data Records (TDR)
                SI.f13/ Data site: Satellite identification number for polar orbit satellite
                    DD.yyyymmdd/ Data Date: year, month, and day,
                       tp.hhnn-hhnnn_ar.nnnnnnn Filename Data Time: Beginning-Ending Time and Area of Data: Satellite orbit number
                SI.f14/ Data site: Satellite identification number for polar orbit satellite
                    DD.yyyymmdd/ Data Date: year, month, and day,
                       tp.hhnn-hhnnn_ar.nnnnnnn Filename Data Time: Beginning-Ending Time and Area of Data: Satellite orbit number
                SI.f15/ Data site: Satellite identification number for polar orbit satellite
                    DD.yyyymmdd/ Data Date: year, month, and day,
                       tp.hhnn-hhnnn_ar.nnnnnnn FilenameData Time: Beginning-Ending Time and Area of Data: Satellite orbit number

Delivery Details

Data files are updated on the FTP server within five minutes of receipt from NESDIS. File names within each satellite orbit covers the area based upon time duration.

 

A sample of the most recently written orbit file (EDR - environmental data ecords) for the F14 satellite is:


SL.us008001/DF.of/DC.sfsat/DS.ssmie/SI.f14/DD.20000425/tp.0540-0650_ar.012345

Data files are written only when data of that subcategory time is available. Further questions or comments concerning data in SL.us008001 path may be directed to nco.idp.dataflow@noaa.gov.

NESDIS provides SSM/I technical documentation and processing source code. Check this NESDIS server.