Update On The NEXRAD Agency Plans
For Near Real-Time WSR-88D Base Data
Collection And Distribution
Tim Crum, Ph.D.
Radar Operations Center (ROC)
NWS Focal Point For WSR-88D Operational Issues
NEXRAD Focal Point For Archive And Real-Time Data Distribution Issues
26 September 2002
OU Stakeholder Workshop On Real-Time WSR-88D Level II Data Held At
University of Oklahoma, Norman, OK
Objectives
 State NEXRAD Agency Requirements For WSR-88D Level II
Archive Data And Near Real-Time Base Data Access
 State NWS Plans For Achieving These Requirements
 State NEXRAD Program Management Committee (NPMC)
Guidelines For Connections To WSR-88D Base Data Streams In
Near Real Time
– Interim
– Final
 Answer Questions/Hear Suggestions
September 2002
Slide 2
NEXRAD Agency Requirements For
WSR-88D Level II Archive Data And
Near Real-Time Base Data Access
 No DOT Or DOD Archive Data Requirements
– NWS Has Funded All Level II Data Collection And Archive
Costs, Beyond DOD Recorder Acquisition
 No DOT Real-Time Base Data Requirements
– No Base Data Distribution System (BDDS) At DOT WSR88Ds
 No DOD Real-Time Base Data Requirements Except At 8 Of 26
DOD WSR-88Ds
– No BDDS At Remaining DOD WSR-88Ds
 NWS Has Archive Data Requirements To Meet R&D, Training,
Testing And Other Agency Needs
September 2002
Slide 3
NEXRAD Agency WSR-88D Data
Requirements
(Continued)
 NWS Near Real-Time Base Data Requirements To Meet NCEP
Operational Requirements
– BDDS On All NWS WSR-88D RPGs
• Each BDDS Has 4 User Ports
– Data Timeliness And Reliability Same As For RPCCDS (<60
Sec And >95%)
 Future NWS Requirements For Archive Or Near Real-Time
Access To New WSR-88D Data/Products To Be Determined –
Not Necessarily All/Any Of The Following Will Be Distributed In
Near Real Time Nor Archived
September 2002
Slide 4
Possible WSR-88D Future Data
Flows
New Requirement
Cumulative
Multiplicative Factor
Possible
Multiplicative
For Data Flow (w.r.t. Implementation Factor For Data
1/20032)
Date
Flow (w.r.t
1/2003)
Max Kbps
Required Per
Radar (Entire
Data Set With
Compression)
4.1 min VCP (Gamma)
TCP/IP Wideband Interface (Msg
Header)
0.25 km Reflectivity Data
0.5 Degree Azimuth Sampling
1.24
Jan-03
1.24
79
1
1.56
2
Jul-04
Oct-04
Jan-05
1.24
1.93
3.86
79
124
247
Doppler Data To End Of 2nd Trip
1.49
Oct-05
5.76
369
1.97
Jan-05
11.35
726
2.32
Jan-08
26.35
1686
Two Different Clutter Filters And
Signal To Noise Ratio Thresholds
Dual Polarization, 4 New
Polarimetric Moments (Differential
Reflectivity, Correlation Coefficient,
Differential Propagation Phase
Shift, and Specific Differential
September 2002
Slide 5
NWS Plans For Achieving These
Requirements
 Archive Data
– Level II Recorders, Circa 1994, Become Unsupportable In
2003
– NWS Planned For Recorder Replacement With Budget
Request
– Proof-Of-Concept CRAFT Project Demonstrated Near RealTime Data Ingestion At NCDC Works
• On-Site Tape Recording Suspended At 55 Sites
 Near Real-Time Data Access For NEXRAD Agency And
External Users Demonstrated In CRAFT
September 2002
Slide 6
NWS Plans For Achieving These
Requirements
(Continued)

ROC Explored 9 Options Of Collecting And Transmitting Level II Data
Electronically
– Lowest Cost Options
• A Combination Of Use Of AWIPS WAN And Private Telco
Frame Relay To Send Data To NWSTG
• A Combination Of Use Of Internet2 And Private Telco Frame
Relay To Send Data To NWSTG
– NWSTG Routes Data To NCDC, NCEP, External Users
– Data Compression on RPG or BDDS (BZIP2)
– NWS Control Over Operationally Required Data Streams
 NWS Expects To
– Determine Final Communications Architecture By End Of 2002
– Begin Turning On Data Flows By Selected Approach NET October
2003
September 2002
Slide 7
NPMC Guidelines For Connections
To WSR-88D Base Data Streams In
Real Time

Intended To Minimize Impact On Forecast Office Staff
 Interim
– NWS Considers Today’s Situation As An “Interim” Phase
– External Groups Can Request Connections To Existing BDDS
• NEXRAD Agency Requirements To Be Met First
• No Compression Equipment Installed, Except For NEXRAD Agency
Users

Final
– NWS Considers The “Final” Phase As When The Last Of The Required
WSR-88D Systems Are Sending Data To The NWSTG
• External Users Receive Data Via Broadcast From NWSTG
• Only NEXRAD Agencies/Federal Agencies Can Connect To BDDS

Guidelines And Other Base Data Information Can Be Found On ROC
Home Page: http://www.osf.noaa.gov/BDCI/
September 2002
Slide 8
Answer Questions And Listen To
Comments And Suggestions
September 2002
Slide 9
Graphic Description
AWIPS WAN Option
NWS
NWSTG
Router/Server
NWS RPG
Processor
(With Compression)
Dedicated
Circuits
AWIPS NCF
AWIPS LAN
TO LAN
Router
RFC
AWIPS Router
Existing Circuits
NCEP
WFO AWIPS
NCDC
External Users
DOD FAA RPG
New Frame Relay
or Digital Services
RPG
Processor
(With
Compression)
CSU/DSU
September 2002
CSU/DSU
Slide 10
Graphic Description
Internet 2 Option
NWS RPG
NWS
NWSTG
NCEP
Ethernet
BDDS
(With Compression)
ISP
Hardware
NCDC
Dedicated Circuits NWSTG
to NCEP and NCDC
DOD or FAA RPG or Remote BDDS located in NWS WFO
BDDS
(With Compression)
September 2002
External Users
ISP
Hardware
Slide 11