Radar Resources / Radar Data / Data Inventory

TDWR Level-III Products
Technical Information Notice


The FAA Terminal Doppler Weather Radar (TDWR) data are now processed by the NWS Supplemental Product Generator (SPG) to create Level-III Products. There are 45 TDWR sites in the United States, providing data in real-time at approximately 5 minute intervals. For more information refer to:

Site ID and Location list: - See Below -
Real-Time data instructions: - See Below -
Historical data: http://www.ncdc.noaa.gov/nexradinv/choosesite.jsp
FAQ: TDWR FAQ

Below is the the Technical Information Notice with details:


NOUS41 KWBC 161915
PNSWSH

TECHNICAL IMPLEMENTATION NOTICE 08-85
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
315 PM EST THU OCT 16 2008

TO:       SUBSCRIBERS:
          - FAMILY OF SERVICES 
          - NOAA WEATHER WIRE SERVICE 
          - EMERGENCY MANAGERS WEATHER INFORMATION NETWORK 
          - NOAAPORT 
          - OTHER NWS PARTNERS...USERS AND EMPLOYEES

FROM:     RICHARD J. VOGT
          DIRECTOR...WSR-88D RADAR OPERATIONS CENTER

SUBJECT:  ADDITION OF PRODUCTS DERIVED FROM FAA TERMINAL DOPPLER 
          WEATHER RADAR TO SBN/NOAAPORT AND RPCCDS: EFFECTIVE 
          NOVEMBER 18 2008 

EFFECTIVE TUESDAY NOVEMBER 18 2008...AT APPROXIMATELY 1500 
COORDINATED UNIVERSAL TIME /UTC/...NWS WILL BEGIN A BETA TEST 
OF DISSEMINATING RADAR PRODUCTS GENERATED BY THE NWS SUPPLEMENTAL 
PRODUCT GENERATOR /SPG/ USING DATA FROM THE FEDERAL AVIATION 
ADMINISTRATION /FAA/ TERMINAL DOPPLER WEATHER RADAR /TDWR/.  
THESE PRODUCTS WILL BE PROVIDED VIA THE RADAR PRODUCT CENTRAL 
COLLECTION DISSEMINATION SERVICE /RPCCDS/. A SUB-SET WILL BE 
PROVIDED VIA NOAAPORT.

BETWEEN NOVEMBER 18 2008 AND JANUARY 2009...PRODUCT DISSEMINATION 
WILL BE PROVIDED FROM UP TO EIGHT BETA TEST SITES. THE REMAINING 
SITES WILL BE GRADUALLY ADDED BETWEEN FEBRUARY AND JUNE 2009. 

TDWR SPG PRODUCTS CONSIST OF A SET OF BASE AND ALGORITHM DERIVED 
PRODUCTS AND CORRESPONDING PARAMETERS LISTED BELOW IN TABLE 1. 
ANALOGOUS TO WSR-88D PRODUCTS ALREADY PROVIDED VIA RPCCDS AND 
NOAAPORT...THESE NEW TDWR SPG PRODUCTS ARE ALSO INTENDED FOR 
DISTRIBUTION IN NEAR REAL-TIME.  THE TDWR DATA ARE PROCESSED BY 
THE NWS SPG...WHICH EVOLVED FROM THE WSR-88D RADAR PRODUCTS 
GENERATOR /RPG/. THUS TDWR SPG PRODUCTS ARE FORMATTED SIMILAR 
TO WSR-88D RPG PRODUCTS. THE TDWR SPG BASE PRODUCTS WILL BE 
PROVIDED AT 150 METER /M/ RANGE RESOLUTION...AND 300M RESOLUTION 
FOR THE LONG RANGE REFLECTIVITY PRODUCT.  ALGORITHM DERIVED 
PRODUCTS WILL BE PROVIDED AT THE SAME RESOLUTION AS THE 
CORRESPONDING WSR-88D PRODUCT.  

AS AN EXAMPLE WORLD METEOROLOGICAL ORGANIZATION /WMO/ PRODUCT 
HEADERS LISTED IN TABLE 1 CORRESPOND TO THE DENVER TDWR /DEN/ 
WHERE SPG PRODUCTS WILL ORIGINATE FROM THE BOULDER /BOU/ WEATHER 
FORECAST OFFICE /WFO/. THE LIST OF 45 TDWR RADARS AND 34 WFOS 
RESPONSIBLE FOR SENDING SPG PRODUCTS ARE LISTED IN TABLE 2.  
THREE TDWR IDS WERE MODIFIED /CLE TO LVE...IND TO IDS...
ICT TO ICH/ SO THAT WMO HEADERS WOULD BE DISTINCT FROM WSR-88D 
HEADERS. FOR THE GENERAL STATUS MESSAGE /GSM/ EXAMPLE...THE 
FULL RANGE OF WFOS...STATE CROSS-REFERENCE NUMBER...AND TDWR 
SPG ARE REFLECTED IN THIS TABLE.

EXCEPT FOR STATUS AND THE FREE TEXT MESSAGES...THE NWS WILL 
DISSEMINATE ONE OF EACH OF THESE TABLE 1 TDWR SPG PRODUCTS EVERY 
SIX MINUTE VOLUME SCAN FROM EACH TDWR SPG. THE HEADER OF EACH 
PRODUCT WILL HAVE A VALID TIME CORRESPONDING TO THE DAY OF MONTH 
AND THE HOUR AND MINUTE OF THE DATA /E.G. 100754 MEANS 0754 
UTC ON THE TENTH DAY OF THE MONTH/. THE TDWR SPG PRODUCTS WILL 
BE DISSEMINATED VIA RPCCDS AND NOAAPORT AND AVAILABLE ON THE 
TELECOMMUNICATION OPERATIONS CENTER /TOC/ FTP SERVER WITHIN 
60 SECONDS AFTER THE VALID TIME.  

AVAILABILITY OF TDWR SPG PRODUCTS MAY BE LESS THAN THAT OF THE 
WSR-88D.  THE FAA ASSUMES NO LIABILITY FOR THE ACCURACY OR 
TIMELINESS OF THE TDWR DATA TRANSFERRED TO THE NWS. THE TDWR 
WILL BE CALIBRATED IN ACCORDANCE WITH STANDARD FAA ORDERS AND 
REPAIRED ACCORDING TO FAA NORMAL MAINTENANCE AND RESTORATION 
SCHEDULES. 

FOR EACH RADAR THE AVERAGE HOURLY DATA VOLUME VIA RPCCDS WILL 
BE APPROXIMATELY 3.9 MEGABYTES /MB/ AND THE DAILY VOLUME WILL BE 
APPROXIMATELY 92.9 MB.  WHEN FULLY IMPLEMENTED THE AVERAGE DAILY 
VOLUME FOR ALL 45 TDWR RADARS WILL BE 4.1 GIGABYTES /GB/.  SINCE 
PRODUCTS VIA NOAAPORT ARE FURTHER COMPRESSED...THE ESTIMATED 
DAILY VOLUME FOR ALL TDWR SPG PRODUCTS IS 2.4 GB.

ALL OF THE PRODUCTS WILL BE PROVIDED BY THE RPCCDS AND WILL BE 
AVAILABLE FROM THE NWS TOC FTP SERVER. EXCEPT FOR STI...HI... 
TVS...AND SPD...ALL PRODUCTS WILL BE CARRIED ON NOAAPORT.  EVERY 
10 SECONDS THE RPCCDS WILL AGGREGATE AND DISSEMINATE BUNDLES OF 
RADAR PRODUCTS /BUNDLES WILL INCLUDE BOTH WSR-88D AND TDWR SPG 
PRODUCTS/.

TABLE 1:  WMO HEADINGS ASSIGNED TO THE TDWR SPG RADAR PRODUCTS

 # TTUSII CCCC NNNXXX SPG PRODUCT CODE AND DESCRIPTION 
 1 NXUS65 KBOU GSMDEN   2 GENERAL STATUS MESSAGE /GSM/ 
 2 NOUS65 KBOU FTMDEN  75 FREE TEXT MESSAGE /FTM/ 
 3 SDUS45 KBOU RSLDEN 152 ARCHIVE STATUS PRODUCT /ASP/ 
 4 SDUS55 KBOU TZLDEN 186 REFLECTIVITY /Z/ - 0.6 DEG. LONG RANGE 
 5 SDUS55 KBOU TR0DEN 181 REFLECTIVITY /Z/ - BASE ELEVATION 
 6 SDUS25 KBOU TR1DEN 181 REFLECTIVITY /Z/ - 1.0 DEG. ELEVATION 
 7 SDUS25 KBOU TR2DEN 181 REFLECTIVITY /Z/ - THIRD ELEVATION 
 8 SDUS55 KBOU TV0DEN 182 VELOCITY /V/ - BASE ELEVATION 
 9 SDUS75 KBOU TV1DEN 182 VELOCITY /V/ - 1.0 DEG. ELEVATION 
10 SDUS75 KBOU TV2DEN 182 VELOCITY /V/ - THIRD ELEVATION 
11 SDUS55 KBOU NCRDEN  37 COMPOSITE REF /CZ/ 
12 SDUS75 KBOU NETDEN  41 ECHO TOPS /ET/ 
13 SDUS35 KBOU NVWDEN  48 VAD WIND PROFILE /VWP/ 
14 SDUS55 KBOU NVLDEN  57 VERT INTEG LIQ /VIL/ 
15 SDUS65 KBOU NSTDEN  58 STORM TRACKING INFORMATION /STI/  
16 SDUS65 KBOU NHIDEN  59 HAIL INDEX /HI/ 
17 SDUS65 KBOU NTVDEN  61 TORNADIC VORTEX SIGNATURE /TVS/ 
18 SDUS35 KBOU N1PDEN  78 ONE HOUR PRECIP /OHP/ 
19 SDUS55 KBOU NTPDEN  80 STORM TOTAL PRECIP /STP/ 
20 SDUS85 KBOU DPADEN  81 DIGITAL PRECIP ARRAY /DPA/ 
21 SDUS65 KBOU SPDDEN  82 SUPPLEMENTAL PRECIPITATION DATA /SPD/ 
22 SDUS55 KBOU DHRDEN  32 DIGITAL HYBRID SCAN REFL /DHR/ 
23 SDUS55 KBOU DSPDEN 138 DIGITAL STORM TOTAL PRECIP /STP/ 
24 SDUS35 KBOU NMDDEN 141 MESOCYCLONE /MD/

TABLE 2:  WMO HEADING...TDWR SITES

 #  TTUSI  I  CCCC  NNN  XXX  TDWR FAA SITE NAME
 1  NXUS6  5  KBOU  GSM  DEN  DENVER /DEN/ 
 2  NXUS6  1  KBOX  GSM  BOS  BOSTON /BOS/ 
 3  NXUS6  1  KCLE  GSM  LVE  CLEVELAND OH /CLE/  
 4  NXUS6  3  KDTX  GSM  DTW  DETROIT /DTW/  
 5  NXUS6  3  KEAX  GSM  MCI  KANSAS CITY /MCI/  
 6  NXUS6  2  KFFC  GSM  ATL  ATLANTA /ATL/ 
 7  NXUS6  4  KFWD  GSM  DAL  DALLAS LOVE FIELD /DAL/ 
 8  NXUS6  4  KFWD  GSM  DFW  DALLAS/FT. WORTH /DFW/  
 9  NXUS6  2  KGSP  GSM  CLT  CHARLOTTE /CLT/ 
10  NXUS6  4  KHGX  GSM  HOU  HOUSTON HOBBY /HOU/  
11  NXUS6  4  KHGX  GSM  IAH  HOUSTON INTERNATIONAL /IAH/  
12  NXUS6  3  KICT  GSM  ICH  WICHITA /ICT/  
13  NXUS6  1  KILN  GSM  CMH  COLUMBUS OH /CMH/  
14  NXUS6  1  KILN  GSM  CVG  COVINGTON /CVG/ 
15  NXUS6  1  KILN  GSM  DAY  DAYTON /DAY/  
16  NXUS6  3  KIND  GSM  IDS  INDIANAPOLIS /IND/  
17  NXUS6  4  KLIX  GSM  MSY  NEW ORLEANS /MSY/  
18  NXUS6  3  KLMK  GSM  SDF  LOUISVILLE KY /SDF/  
19  NXUS6  3  KLOT  GSM  MDW  CHICAGO MIDWAY /MDW/  
20  NXUS6  3  KLOT  GSM  ORD  CHICAGO O'HARE /ORD/  
21  NXUS6  3  KLSX  GSM  STL  ST. LOUIS /STL/ 
22  NXUS6  1  KLWX  GSM  ADW  ANDREWS AIR FORCE BASE /ADW/ 
23  NXUS6  1  KLWX  GSD  BWI  BALTIMORE/WASH /BWI/ 
24  NXUS6  1  KLWX  GSM  DCA  WASHINGTON NATIONAL /DCA/ 
25  NXUS6  1  KLWX  GSM  IAD  DULLES /IAD/ 
26  NXUS6  4  KMEG  GSM  MEM  MEMPHIS /MEM/ 
27  NXUS6  2  KMFL  GSM  FLL  FORT LAUDERDALE /FLL/  
28  NXUS6  2  KMFL  GSM  MIA  MIAMI /MIA/ 
29  NXUS6  2  KMFL  GSM  PBI  WEST PALM BEACH /PBI/ 
30  NXUS6  2  KMLB  GSM  MCO  ORLANDO INTERNATIONAL /MCO/  
31  NXUS6  3  KMKX  GSM  MKE  MILWAUKEE /MKE/  
32  NXUS6  3  KMPX  GSM  MSP  MINNEAPOLIS /MSP/ 
33  NXUS6  4  KOHX  GSM  BNA  NASHVILLE /BNA/ 
34  NXUS6  1  KOKX  GSM  EWR  NEWARK /EWR/  
35  NXUS6  1  KOKX  GSM  JFK  NEW YORK CITY /JFK/ 
36  NXUS6  4  KOUN  GSM  OKC  OKLAHOMA CITY /OKC/  
37  NXUS6  1  KPBZ  GSM  PIT  PITTSBURGH /PIT/ 
38  NXUS6  1  KPHI  GSM  PHL  PHILADELPHIA /PHL/ 
39  NXUS6  5  KPSR  GSM  PHX  PHOENIX /PHX/  
40  NXUS6  2  KRAH  GSM  RDU  RALEIGH DURHAM /RDU/  
41  NXUS6  5  KSLC  GSM  SLC  SALT LAKE CITY /SLC/  
42  NXUS6  2  KTBW  GSM  TPA  TAMPA BAY /TPA/  
43  NXUS6  4  KTSA  GSM  TUL  TULSA /TUL/  
44  NXUS6  5  KVEF  GSM  LAS  LAS VEGAS /LAS/ 
45  NXUS6  2  TJSJ  GSM  SJU  SAN JUAN /SJU/

WITHIN THE TOC FTP SERVER...TDWR SPG PRODUCTS WILL BE PLACED 
IN SUBDIRECTORIES BELOW THE FOLLOWING DIRECTORY:

  FTP://TGFTP.NWS.NOAA.GOV/SL.US008001/DF.OF/DC.RADAR/

PRODUCT FILES WILL BE PLACED IN SITE NAMED SUBDIRECTORIES AS 
LISTED IN TABLE 4 BENEATH THE PRODUCT NAMED SUBDIRECTORIES LISTED 
IN TABLE 3. NOTE THAT TDWR SITE NAMED DIRECTORIES ARE EASILY 
IDENTIFIED BY THE T PREFIX TO THE XXX SPG SITE ID.  

FOR SPG PRODUCTS WHICH HAVE A WSR-88D COUNTERPART... PRODUCTS WILL 
BE PLACED IN TDWR SPG SITE NAMED SUBDIRECTORIES BENEATH EXISTING 
WSR-88D PRODUCT NAMED DIRECTORIES. ERRONEOUS WSR-88D PRODUCT NAMED 
SUBDIRECTORIES WILL BE CORRECTED BY THE TECHNOLOGY REFRESHED RPCCDS 
/E.G. DS.00NMD BECOMES DS.141MD/.  WITHIN EACH SITE NAMED 
SUBDIRECTORY...RADAR PRODUCT FILES FOR THE CURRENT VOLUME SCAN AND 
THE PREVIOUS 250 VOLUME SCANS WILL BE STORED. THE FILES IN EACH 
RADAR SITE SUBDIRECTORY WILL BE SEQUENTIALLY NAMED SN.0000 THROUGH 
SN.0250...AND SN.LAST.  EACH VOLUME SCAN...NEW FILES WILL BE WRITTEN 
TO THE CURRENT FILE NAME SN.LAST AND THE NEXT SEQUENTIALLY NUMBERED 
FILE...OVERWRITING THE FILE CORRESPONDING TO THE PREVIOUSLY CURRENT 
PRODUCT AND THE OLDEST FILE IN THE DIRECTORY /USE LOWER CASE LETTERS 
FOR ALL FILE NAMES/.  THE RESIDENCE TIME OF TDWR SPG FILES WILL BE 
APPROXIMATELY ONE DAY. 

TABLE 3:  TOC FTP DIRECTORIES ASSIGNED THE TDWR SPG PRODUCTS

 # DIRECTORY    SPG PRODUCT CODE AND DESCRIPTION
 1 /DS.P2GSM/     2 GENERAL STATUS MESSAGE /GSM/ 
 2 /DS.75FTM/    75 FREE TEXT MESSAGE /FTM/ 
 3 /DS.152RS/   152 ARCHIVE STATUS PRODUCT /ASP/
 4 /DS.186ZL/   186 REFLECTIVITY /Z/ - 0.6 DEG. LONG RANGE 
 5 /DS.181R0/   181 REFLECTIVITY /Z/ - BASE ELEVATION 
 6 /DS.181R1/   181 REFLECTIVITY /Z/ - 1.0 DEG. ELEVATION 
 7 /DS.181R2/   181 REFLECTIVITY /Z/ - THIRD ELEVATION 
 8 /DS.182V0/   182 VELOCITY /V/ - BASE ELEVATION 
 9 /DS.182V1/   182 VELOCITY /V/ - 1.0 DEG. ELEVATION 
10 /DS.182V2/   182 VELOCITY /V/ - THIRD ELEVATION 
11 /DS.P37CR/    37 COMPOSITE REF /CZ/ 
12 /DS.P41ET/    41 ECHO TOPS /ET/ 
13 /DS.48VWP/    48 VAD WIND PROFILE /VWP/ 
14 /DS.57VIL/    57 VERT INTEG LIQ /VIL/ 
15 /DS.58STI/    58 STORM TRACKING INFORMATION /STI/ 
16 /DS.P59HI/    59 HAIL INDEX /HI/ 
17 /DS.61TVS/    61 TORNADIC VORTEX SIGNATURE /TVS/ 
18 /DS.78OHP/    78 ONE HOUR PRECIP /OHP/ 
19 /DS.80STP/    80 STORM TOTAL PRECIP /STP/ 
20 /DS.81DPR/    81 DIGITAL PRECIP ARRAY /DPA/ 
21 /DS.82SPD/    82 SUPPLEMENTAL PRECIPITATION DATA /SPD/ 
22 /DS.32DHR/    32 DIGITAL HYBRID SCAN REFL /DHR/ 
23 /DS.138DP/   138 DIGITAL STORM TOTAL PRECIP /STP/ 
24 /DS.141MD/   141 MESOCYCLONE /MD/

TABLE 4:  TOC FTP DIRECTORIES ASSIGNED THE TDWR SPG SITES

 #  DIRECTORY  SPG ID  TDWR FAA SITE NAME
 1  /SI.TDEN/  3013    DENVER /DEN/
 2  /SI.TBOS/  3004    BOSTON /BOS/
 3  /SI.TLVE/  3006    CLEVELAND OH /CLE/
 4  /SI.TDTW/  3015    DETROIT /DTW/
 5  /SI.TMCI/  3025    KANSAS CITY /MCI/
 6  /SI.TATL/  3002    ATLANTA /ATL/
 7  /SI.TDAL/  3010    DALLAS LOVE FIELD /DAL/
 8  /SI.TDFW/  3014    DALLAS/FT. WORTH /DFW/
 9  /SI.TCLT/  3007    CHARLOTTE /CLT/
10  /SI.THOU/  3018    HOUSTON HOBBY /HOU/
11  /SI.TIAH/  3020    HOUSTON INTERNATIONAL /IAH/
12  /SI.TICH/  3021    WICHITA /ICT/
13  /SI.TCMH/  3008    COLUMBUS OH /CMH/
14  /SI.TCVG/  3009    COVINGTON /CVG/
15  /SI.TDAY/  3011    DAYTON /DAY/
16  /SI.TIDS/  3022    INDIANAPOLIS /IND/
17  /SI.TMSY/  3032    NEW ORLEANS /MSY/
18  /SI.TSDF/  3040    LOUISVILLE KY /SDF/
19  /SI.TMDW/  3027    CHICAGO MIDWAY /MDW/
20  /SI.TORD/  3034    CHICAGO O'HARE /ORD/
21  /SI.TSTL/  3043    ST. LOUIS /STL/
22  /SI.TADW/  3001    ANDREWS AIR FORCE BASE /ADW/
23  /SI.TBWI/  3005    BALTIMORE/WASH /BWI/
24  /SI.TDCA/  3012    WASHINGTON NATIONAL /DCA/
25  /SI.TIAD/  3019    DULLES /IAD/
26  /SI.TMEM/  3028    MEMPHIS /MEM/
27  /SI.TFLL/  3017    FORT LAUDERDALE /FLL/
28  /SI.TMIA/  3029    MIAMI /MIA/
29  /SI.TPBI/  3035    WEST PALM BEACH /PBI/
30  /SI.TMKE/  3030    MILWAUKEE /MKE/
31  /SI.TMCO/  3026    ORLANDO INTERNATIONAL /MCO/
32  /SI.TMSP/  3031    MINNEAPOLIS /MSP/
33  /SI.TBNA/  3003    NASHVILLE /BNA/
34  /SI.TEWR/  3016    NEWARK /EWR/
35  /SI.TJFK/  3023    NEW YORK CITY /JFK/
36  /SI.TOKC/  3033    OKLAHOMA CITY /OKC/
37  /SI.TPIT/  3038    PITTSBURGH /PIT/
38  /SI.TPHL/  3036    PHILADELPHIA /PHL/
39  /SI.TPHX/  3037    PHOENIX /PHX/
40  /SI.TRDU/  3039    RALEIGH DURHAM /RDU/
41  /SI.TSLC/  3042    SALT LAKE CITY /SLC/
42  /SI.TTPA/  3044    TAMPA BAY /TPA/
43  /SI.TTUL/  3045    TULSA /TUL/
44  /SI.TLAS/  3024    LAS VEGAS /LAS/
45  /SI.TSJU/  3041    SAN JUAN /SJU/

THE NWS HAS ESTABLISHED THE FOLLOWING FTP SITE TO PROVIDE PROJECT 
PLANS AND STATUS...ADDITIONAL INFORMATION...AND FOR PREVIEWING 
SAMPLE TDWR SPG PRODUCTS:

 FTP://FTP.ROC.NOAA.GOV/PUB/TDWR_SPG_INFO/

BEGINNING ON A DATE TO BE ANNOUNCED...THE INFORMATION WILL MOVE TO:

 HTTP://WWW.ROC.NOAA.GOV/

IF YOU HAVE QUESTIONS ABOUT THE TECHNICAL CONTENT OR GENERATION 
OF THESE PRODUCTS...PLEASE CONTACT: 

 MICHAEL ISTOK 
 NWS...OFFICE OF SCIENCE AND TECHNOLOGY
 SILVER SPRING MARYLAND
 301 713 0763 EXT 103 
 MICHAEL.ISTOK@NOAA.GOV

 ALTERNATE 
 TIM.D.CRUM@NOAA.GOV

IF YOU HAVE QUESTIONS ABOUT THE NOAAPORT ACTIVATION OR DATA FLOW 
OF THESE PRODUCTS...PLEASE CONTACT:  
 
 BRIAN GOCKEL  
 NWS...OFFICE OF SCIENCE AND TECHNOLOGY  
 SILVER SPRING...MARYLAND    
 301 713 0304 EXT 158 
 BRIAN.GOCKEL@NOAA.GOV

THE CENTRALLY COLLECTED TDWR SPG PRODUCTS WILL BE ARCHIVED AT THE 
NATIONAL CLIMATIC DATA CENTER /NCDC/ JUST AS THE WSR-88D PRODUCTS 
ARE. THE INVENTORY OF THE ARCHIVED PRODUCTS WILL BE AT: 

HTTP://HURRICANE.NCDC.NOAA.GOV/PLS/PLHAS/HAS.DSSELECT  

THE TDWR LEVEL II DATA WILL NOT BE COLLECTED... DISTRIBUTED OR 
ARCHIVED AT THIS TIME.

NWS TECHNICAL IMPLEMENTATION NOTICES ARE ONLINE AT /USE LOWER CASE/: 

  HTTP://WWW.WEATHER.GOV/OS/NOTIF.HTM

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