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20041006: NEXRAD station elevations in McIDAS STNLIST



>From: Don Murray <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200410061525.i96FOxUF010647 McIDAS STNDB NEXRAD elevations

Don,

>The station elevations for most of the NEXRAD stations in
>McIDAS seem to be wrong.  Comparing with the GEMPAK list
>(and spotty checks with the online NWS documentation), most
>elevations are listed as too high (some off by almost 1000 meters).
>Even adding in the antenna height does not account for
>the discrepency.  I've attached a comparison of McIDAS and
>GEMPAK elevations.  McIDAS data was gotten using:
>
>STNLIST CO=US TYPE=N

I am CCing this to SSEC.

Several years ago, before the McIDAS station table included NEXRAD
information, I generated an ASCII table of NEXRAD station information
from values I snarfed from an NWS web site;  I have been including that
table in my distributions ever since.  A quick check of a few stations
shows that the elevations in the file ~mcidas/data/NEXRAD.DAT seem to
show favorable comparisons with the values you list from GEMPAK.  I
will compare the rest of the location and elevation values against what
the NWS has on their NEXRAD web pages.

Interestingly, the ratio of the McIDAS STNDB NEXRAD elevations to
the GEMPAK elevations is nearly constant:

ID  eleG/eleM   ratio
---+-----------+-----
ABC 61/49     = 1.25
ABR 501/397   = 1.26
ABX 2258/1789 = 1.26
ACG 79/63     = 1.25
AEC 20/16     = 1.25
AHG 93/74     = 1.26

(I only checked the first 6; the other ratios may differ).

I don't know if this is significant, but it "feels" as though there
should be a simple reason for the difference.

>I removed some of the information from the output and added
>another column for the corresponding GEMPAK elevations for
>each station.  I have not verified all of the GEMPAK elevations,
>nor checked consistency for lat/lon information.
>
>This came up as an IDV user support question since we used
>the output of the STNLIST command to generate the IDV nexrad
>station list.  We'll switch to using the GEMPAK table for the
>next release.

> ID     Station Name         LAT        LON         ELE    GEMPAK ELE
> -----  -------------------- ---------- ----------  ----   ----------
> ABC    BETHEL                 60:47:31  161:52:35    61       49
> ABR    ABERDEEN               45:27:21   98:24:47   501      397
> ABX    ALBUQUERQUE            35:08:59  106:49:26  2258     1789
> ACG    JUNEAU                 56:51:10  135:31:45    79       63
> AEC    Nome                   64:30:41  165:17:42    20       16
> AHG    KENAI                  60:43:33  151:21:05    93       74
> AIH    MIDDLETON ISLAND       59:27:41  146:18:11    25       20
> AKC    KING SALMON            58:40:46  156:37:46    24       19
> AKQ    WAKEFIELD              36:59:02   77:00:26    43       34
> AMA    AMARILLO               35:14:00  101:42:33  1380     1093
> AMX    MIAMI                  25:36:40   80:24:46     5        4
> APD    FAIRBANKS              65:02:06  147:30:06   997      790
> APX    NORTH CENTRAL LOWER    44:54:26   84:43:11   563      446
> ARX    LA CROSSE              43:49:22   91:11:28   491      389
> ATX    SEATTLE/TACOMA         48:11:40  122:29:45   190      151
> BBX    Beale Air Force Base   39:29:46  121:37:54    66       53
> BGM    BINGHAMTON             42:11:59   75:59:05   617      490
> BHX    EUREKA                 40:29:54  124:17:31   924      732
> BIS    BISMARCK               46:46:15  100:45:38   637      505
> BLX    BILLINGS               45:51:14  108:36:24  1384     1097
> BMX    BIRMINGHAM             33:10:20   86:46:11   248      197
> BOX    BOSTON                 41:57:21   71:08:13    45       46
> BRO    BROWNSVILLE            25:54:58   97:25:08     8        7
> BUF    BUFFALO                42:56:56   78:44:12   266      211
> BYX    Key West               24:35:51   81:42:11     3        2
> CAE    COLUMBIA               33:56:55   81:07:06    88       70
> CBW    Caribou                46:02:21   67:48:23   287      227
> CBX    BOISE                  43:29:26  116:14:08  1177      933
> CCX    CENTRAL PENNSYLVANIA   40:55:23   78:00:13   925      733
> CLE    CLEVELAND              41:24:47   81:51:35   293      233
> CLX    CHARLESTON             32:39:20   81:02:32    37       30
> CRP    CORPUS CHRISTI         27:47:03   97:30:40    17       14
> CXX    BURLINGTON             44:30:40   73:10:01   121       97
> CYS    CHEYENNE               41:09:07  104:48:22  2358     1868
> DAX    SACRAMENTO             38:30:04  121:40:40    11        9
> DDC    DODGE CITY             37:45:39   99:58:08   996      789
> DFX    Laughlin Air Force B   29:16:22  100:16:50   435      345
> DGX    Brandon                32:16:47   89:59:03   150      186
> DIX    PHILADELPHIA           39:56:49   74:24:39    57       45
> DLH    DULUTH                 46:50:13   92:12:35   549      435
> DMX    DES MOINES             41:43:52   93:43:22   377      299
> DOX    Dover Air Force Base   38:49:32   75:26:23    19       15
> DTX    DETROIT                42:41:59   83:28:18   412      327
> DVN    QUAD CITIES            41:36:42   90:34:51   290      230
> DYX    SAN ANGELO             32:32:18   99:15:16   583      462
> EAX    KANSAS CITY/PLEASANT   38:48:37   94:15:52   382      303
> EMX    TUCSON                 31:53:37  110:37:49  2002     1586
> ENX    ALBANY                 42:35:11   74:03:50   702      557
> EOX    FORT RUCKER            31:27:38   85:27:34   167      132
> EPZ    EL PASO                31:52:23  106:41:53  1579     1251
> ESX    LAS VEGAS              35:42:04  114:53:29  1872     1483
> EVX    Northern Florida       30:33:52   85:55:17    53       43
> EWX    AUSTIN/SAN ANTONIO     29:42:14   98:01:42   243      193
> EYX    Edwards Air Force Ba   35:05:52  117:33:39  1060      840
> FCX    ROANOKE                37:01:28   80:16:26  1103      874
> FDR    Frederick              34:21:44   98:58:35   487      386
> FDX    Cannon Air Force Bas   34:38:07  103:37:48  1789     1417
> FFC    ATLANTA                33:21:49   84:33:57   330      262
> FSD    SIOUX FALLS            43:35:16   96:43:46   550      436
> FSX    FLAGSTAFF              34:34:28  111:11:52  2854     2261
> FTG    DENVER/BOULDER         39:47:12  104:32:45  1676     1675
> FWS    DALLAS/FORT WORTH      32:34:23   97:18:11   262      208
> GGW    GLASGOW                48:12:23  106:37:30   875      694
> GJX    GRAND JUNCTION         39:03:44  108:12:50  3844     3045
> GLD    GOODLAND               39:22:01  101:42:01  1404     1113
> GRB    GREEN BAY              44:29:54   88:06:41   262      208
> GRK    Central Texas          30:43:19   97:22:59   207      164
> GRR    GRAND RAPIDS           42:53:38   85:32:41   299      237
> GSP    GREENVILLE/SPARTANBU   34:53:00   82:13:12   361      287
> GUA    GUAM                   13:27:16 -144:48:30   101       80
> GWX    Columbus Air Force B   33:53:48   88:19:44   183      145
> GYX    PORTLAND               43:53:29   70:15:23   157      125
> HDX    Holloman Air Force B   33:04:35  106:07:22  1624     1286
> HGX    HOUSTON/GALVESTON      29:28:19   95:04:45     6        5
> HKI    Kauai                  21:53:39  159:33:08    68       55
> HKM    Kohala                 20:07:32  155:46:40  1466     1162
> HMO    Molokai                21:07:58  157:10:48   524      415
> HNX    SAN JOAQUIN VALLEY     36:18:51  119:37:56    93       74
> HPX    Fort Campbell          36:44:12   87:17:06   221      176
> HTX    NORTHERN ALABAMA       34:55:50   86:05:00   677      536
> HWA    South Shore Hawaii     19:05:42  155:34:08   531      421
> ICT    WICHITA                37:39:17   97:26:34   513      407
> ICX    Cedar City             37:35:27  112:51:44   230     3231
> ILN    CINCINNATI             39:25:13   83:49:18   406      322
> ILX    CENTRAL ILLINOIS       40:09:02   89:20:13   223      177
> IND    INDIANAPOLIS           39:42:27   86:16:49   303      241
> INX    TULSA                  36:10:30   95:33:53   257      204
> IWA    PHOENIX                33:17:21  111:40:12   520      412
> IWX    NORTHERN INDIANA       41:21:32   85:42:00   369      293
> JAN    JACKSON                32:19:04   90:04:48   114       91
> JAX    JACKSONVILLE           30:29:05   81:42:07    12       10
> JGX    Robins Air Force Bas   32:40:31   83:21:04   200      159
> JKL    JACKSON                37:35:27   83:18:47   524      416
> JUA    SAN JUAN               18:06:56   66:04:41  1075      852
> LBB    LUBBOCK                33:39:15  101:48:51  1254      993
> LCH    LAKE CHARLES           30:07:31   93:12:57     5        4
> LIX    NEW ORLEANS/BATON RO   30:20:12   89:49:32     9        7
> LNX    NORTH PLATTE           41:57:28  100:34:35  1142      905
> LOT    CHICAGO                41:36:17   88:05:05   255      202
> LRX    ELKO                   40:44:23  116:48:10  2595     2056
> LSX    ST. LOUIS              38:41:56   90:40:58   233      185
> LTX    WILMINGTON             33:59:22   78:25:44    24       30
> LVX    LOUISVILLE             37:58:31   85:56:38   276      219
> LWX    BALTIMORE              38:58:31   77:28:40   104       83
> LZK    LITTLE ROCK            34:50:11   92:15:44   218      173
> MAF    MIDLAND/ODESSA         31:56:36  102:11:21  1103      874
> MAX    MEDFORD                42:04:52  122:43:02  2891     2290
> MBX    Minot Air Force Base   48:23:33  100:51:54   574      455
> MHX    MOREHEAD CITY          34:46:34   76:52:34    11        9
> MKX    MILWAUKEE              42:58:04   88:33:02   368      292
> MLB    MELBOURNE              28:06:48   80:39:15    13       11
> MOB    MOBILE                 30:40:46   88:14:23    80       63
> MPX    MINNEAPOLIS            44:50:56   93:33:56   364      288
> MQT    MARQUETTE              46:31:52   87:32:54   542      430
> MRX    KNOXVILLE/TRI-CITIES   36:10:07   83:24:06   514      408
> MSX    MISSOULA               47:02:28  113:59:10  3022     2394
> MTX    SALT LAKE CITY         41:15:46  112:26:52  2485     1969
> MUX    SAN FRANCISCO BAY AR   37:09:19  121:53:54  1334     1057
> MVX    EASTERN NORTH DAKOTA   47:31:40   97:19:32   379      301
> MXX    EASTERN ALABAMA        32:32:12   85:47:23   153      122
> NKX    SAN DIEGO              32:55:08  117:02:31   367      291
> NQA    MEMPHIS                35:20:41   89:52:24   108       86
> OAX    OMAHA                  41:19:13   96:22:00   441      350
> OHX    NASHVILLE              36:14:50   86:33:45   222      176
> OKX    NEW YORK CITY          40:51:56   72:51:50    32       26
> OTX    SPOKANE                47:40:49  117:37:36   917      727
> PAH    PADUCAH                37:04:06   88:46:19   150      119
> PBZ    PITTSBURGH             40:31:54   80:13:05   455      361
> PDT    PENDLETON              45:41:26  118:51:10   582      462
> POE    Fort Polk              31:09:20   92:58:33   156      124
> PUX    PUEBLO                 38:27:34  104:10:53  1600     1600
> RAX    RALEIGH/DURHAM         35:39:56   78:29:23   133      106
> RGX    RENO                   39:45:15  119:27:44  3193     2530
> RIW    RIVERTON               43:03:58  108:28:38  2142     1697
> RLX    CHARLESTON             38:18:40   81:43:23   415      329
> RTX    PORTLAND               45:42:53  122:57:55   604      479
> SFX    POCATELLO/IDAHO FALL   43:06:21  112:41:10  1721     1364
> SGF    SPRINGFIELD            37:14:07   93:24:02   491      390
> SHV    SHREVEPORT             32:27:03   93:50:29   105       83
> SJT    SAN ANGELO             31:22:17  100:29:33   727      576
> SOX    Santa Ana Mountains    33:49:04  117:38:09  1164      923
> SRX    Western Arkansas/For   35:17:26   94:21:42   246      195
> TBW    TAMPA BAY AREA         27:42:20   82:24:06    15       12
> TFX    GREAT FALLS            47:27:35  111:23:07  1429     1132
> TLH    TALLAHASSEE            30:23:51   84:19:44    24       19
> TLX    OKLAHOMA CITY          35:19:59   97:16:40   466      370
> TWX    TOPEKA                 38:59:49   96:13:57   526      417
> TYX    Montague               43:45:21   75:40:48   709      562
> UDX    RAPID CITY             44:07:30  102:49:47  1160      919
> UEX    HASTINGS               40:19:15   98:26:31   760      602
> VAX    Moody Air Force Base   30:53:25   83:00:06    68       54
> VBX    Vandenberg Air Force   34:50:17  120:23:49   470      373
> VNX    Vance Air Force Base   36:44:27   98:07:40   465      369
> VTX    LOS ANGELES            34:24:42  119:10:46  1048      831
> VWX    Evansville             38:15:37   87:43:28   187      190
> YUX    Yuma                   32:29:43  114:39:24    66       53

Tom
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>From address@hidden  Wed Oct  6 10:37:44 2004

Thanks, Tom.

I too was thinking that there must be a consistent reason for
the offset (higher elevations having higher spreads in actual
differences).  I was thinking maybe it was a transpose in the
code to go from feet to meters or something like that.  Also,
I noted that GEMPAK seems to have truncated the station elevations
rather than rounded them.

I'll take a look at the other table you mentioned.

Don


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