ASCII Upper Air File

This type of file is generated by the uacvt program for use with other WXP upper air display programs.

FORMAT

The format of the file is as follows:

WXPUPAx
hhZ dd mmm yy
wwwww:iiii:aaaa:oooo 00HHH TTTtt dddff 92HHH TTTtt dddff 85HHH TTTtt dddff 70HHH TTTtt dddff
50HHH TTTtt dddff 40HHH TTTtt dddff 30HHH TTTtt dddff 25HHH TTTtt dddff
20HHH TTTtt dddff 15HHH TTTtt dddff 10HHH TTTtt dddff 07HHH TTTtt dddff
05HHH TTTtt dddff 03HHH TTTtt dddff 02HHH TTTtt dddff 01HHH TTTtt dddff
88ppp TTTtt dddff 77ppp dddff
ppp TTTtt ppp TTTtt ...
ppp TTTtt ppp TTTtt ... X
hh dddff hh dddff ...
hh dddff hh dddff ... $

Header Format

The first line of the file is the string:

WXPUPAx

which is used to determine file type. The second line of the data file contains the date and time in the following format:

hhZ dd mmm yy

Where:

hh -- Hour of the observation in GMT

dd -- Day of the observation

mmm -- A three letter abbreviation for the month
yy -- The last two digits of the year

Example: 12Z 24 JUN 98

Data Format

The data are entered on the following lines. This format listed below contains twelve lines of data for each individual station, which are in the following format:

Line 1-5: Mandatory level data to 500 mb (from TTAA, TTCC, or PPAA)

[wwwww:]iiii[:aaaa:oooo] 00HHH TTTtt dddff 92HHH TTTtt dddff 85HHH TTTtt dddff 70HHH TTTtt dddff
50HHH TTTtt dddff 40HHH TTTtt dddff 30HHH TTTtt dddff 25HHH TTTtt dddff
20HHH TTTtt dddff 15HHH TTTtt dddff 10HHH TTTtt dddff 07HHH TTTtt dddff
05HHH TTTtt dddff 03HHH TTTtt dddff 02HHH TTTtt dddff 01HHH TTTtt dddff
88ppp TTTtt dddff 77ppp dddff

Where:

• wwwww -- WMO number for the observation site (optional).
• iiii -- ICAO Station identifier.
  If the station does not have an ICAO ID, one will be derived from the WMO number using the 2 letter country prefix and the last 3 numbers of the WMO number.  Country prefixes are listed in the Global Station Information Appendix.
• aaaa -- Station latitude (optional).
• oooo -- Station longitude (optional).
• PP -- Pressure level (see below). The value "88" represents tropopause data. The value "77" represents maximum wind level data.  In these cases pressure of the level is reported instead of height.
• ppp -- Pressure of level. (999 for missing)
• HHH -- Height in meters. (999 for missing)
  

  PP	Pressure	Code(H)	Height	Code(H)	Height
  00	1000 mb	H < 500	H	H >= 500	500-H
  92	925 mb	all H	H
  85	850 mb	all H	H+1000
  70	700 mb	H < 500	H+3000	H >= 500	H+2000
  50	500 mb	all H	H*10
  40	400 mb	all H	H*10
  30	300 mb	H < 500	H*10+10000	H >= 500	H*10
  25	250 mb	H < 500	H*10+10000	H >= 500	H*10
  20	200 mb	all H	H*10+10000
  15	150 mb	all H	H*10+10000
  10	100 mb	all H	H*10+10000
  07	70 mb	all H	H*10+10000
  05	50 mb	H < 500	H*10+20000	H >= 500	H*10+10000
  03	30 mb	all H	H*10+20000
  02	20 mb	all H	H*10+20000
  01	10 mb	H < 500	H*10+30000	H >= 500	H*10+20000

• TTT -- Temperature at the pressure level in .1 C. (999 for missing)
  If the tenths digit is odd, the temperature is negative. Otherwise, the temperature is positive. For example, 234 is 23.4C whereas 123 is -12.3C.
• tt -- Dewpoint depression in C. (99 for missing)
  If tt is less than or equal to 50, then the dewpoint depression is in tenths of a C. Otherwise, tt is the dewpoint depression in C plus 50. For example, 65 gives a dewpoint depression of 15C, whereas 17 gives a depression of 1.7C.
• ddd -- Wind direction to the nearest 5 degrees (999 for missing)
• ff -- Wind speed in knots (99 for missing)
  If ddd is not an even multiple of 5, the difference between ddd and an even multiple of 5 is then added to the wind speed as the hundredths digit. For example, 31523 (dddff) is 315_ at 23 knots whereas 25612 is 255_ at 112 knots.

If all the information for a particular group is missing, it is encoded as an "X".

Next Lines: Significant reporting levels ( 50 maximum from TTBB and TTDD reports)

Format:

ppp TTTtt ppp TTTtt ...

Where:

• ppp -- Pressure of significant level
  If pressure is greater than 1000 mb, ppp is the pressure minus 1000.
• TTTtt -- is encoded same as TTAA data listed above.

Information terminated with "X"

Next Lines: Wind level information (50 maximum from PPBB and PPDD reports)

Format:

hh dddff hh dddff ...

Where:

• hh -- Height of the wind level is 1000s of feet.
• dddff -- is encoded as listed above

Information terminated with "$"

EXAMPLES

An example of a converted report would be as follows:

72456:KTOP:39.07:-95.62 00121 X X 92806 22212 19012 85541 18618 24019 70189 10459 25042
50589 06164 26032 40760 16718 23537 30971 30758 24035 25097 41358 23538
20245 53557 24043 15425 64963 25515 10672 64566 28503 07889 62372 07014
05100 57575 05012 X X X X X X X X X
88147 65763 26016 X X
983 26639 947 23019 890 21628 839 17817 819 18257 788 15856 769 16058
678 08860 592 01501 548 04300 533 04911 526 06156 525 05959 510 05359
484 07565 479 08361 476 08548 448 11907 390 18309 359 21346 317 28550
286 33360 235 44760 216 49556 183 57559 133 66762  94 64967  92 65967
 61 60174  45 56375 X
00 12007 01 12507 02 14511 03 22514 04 24018 06 23520 07 23523
08 24531 09 25537 10 25540 11 24545 12 24044 14 24538 16 26026
18 26526 20 25535 25 23537 26 23038 30 24037 35 23534 43 25544
44 26012 46 24513 49 27514 50 28008 54 29502 55 28503 62 06511
63 09011 70 05018 $

Where:

• KTOP is Topeka KS (WMO 72456, Lat=39.07, Lon=-95.62)

Mandatory level data (miss is missing data)

Code	Level	Pres (mb)	Hght (m)	Temp (C)	Depr (C)	W Dir (deg)	W Spd (knt)
00121 X X		1000	121	miss	miss	miss	miss
92806 22212 19012		925	806	22.2	1.2	190	12
85541 18618 24019		850	1541	18.6	1.8	240	19
70189 10459 25042		700	3189	10.4	9	250	42
50589 06164 26032		500	5890	-6.1	14	260	32
40760 16718 23537		400	7600	-16.7	1.8	235	37
30971 30758 24035		300	9710	-30.7	8	240	35
25097 41358 23538		250	10970	-41.3	8	235	38
20245 53557 24043		200	12450	-53.5	7	240	43
15425 64963 25515		150	14250	-64.9	13	255	15
10672 64566 28503		100	16720	-64.5	16	285	3
07889 62372 07014		70	18890	-62.3	22	70	14
05100 57575 05012		50	20100	-57.5	25	50	12
X X X		30	miss	miss	miss	miss	miss
X X X		20	miss	miss	miss	miss	miss
X X X		10	miss	miss	miss	miss	miss
88147 65763 26016	Trop	147		-65.7	13	260	16
X X	Max Wind	miss				miss	miss

Significant level data

Code	Level	Pres (mb)	Temp (C)	Depr (C)
983 26639	SFC	983	26.6	3.9
947 23019		947	23.0	1.9
890 21628		890	21.6	2.8
839 17817		839	17.8	1.7
819 18257		819	18.2	7
788 15856		788	15.8	6
769 16058		769	16.0	8
...
133 66762		133	-66.7	12
94 64967		94	-64.9	17
92 65967		92	-65.9	17
61 60174		61	-60.1	24
45 56375		45	-56.3	25

Wind level data

Code	Level	Hght (ft)	W Dir (deg)	W Spd (knt)
00 12007	SFC	SFC	120	7
01 12507		1000	125	7
02 14511		2000	145	11
03 22514		3000	225	14
04 24018		4000	240	18
06 23520		6000	235	20
07 23523		7000	235	23
...
54 29502		54000	295	2
55 28503		55000	285	3
62 06511		62000	65	11
63 09011		63000	90	11
70 05018		70000	50	18

A sample upper air converted file would look like:

WXPUPAx
0000Z  3 AUG 98
01001:ENJA:70.93:-8.67 00047 06612 15514 92686 04203 16518 85374 05256 17517 709
33 03567 15520
50552 16929 15020 40716 27923 17021 30916 43199 21019 25036 53999 22015
20178 48799 20012 15370 45199 22511 10640 45599 22510 07879 44399 20007
05104 44999 26506 03446 43199 00000 02722 39387 13514 01201 X X
88227 58399 22018 X X
005 06010 993 06806 894 03004 855 05250 779 01270 731 02365 644 06576
613 09758 585 12365 573 13562 558 15514 528 17507 522 16115 468 19727
393 29120 389 28949 368 31362 314 40799 239 56799 227 58399 214 58799
205 49599 193 47999 171 45399 127 44399  89 45999  33 44399  17 39787
 15 34589  14 37188  11 36588 X
00 13509 $
01028:ENBJ:74.52:19.02 00088 05834 26510 92720 00400 29014 85397 00507 30522 709
40 06550 29015
...

FILES

• upa.cty -- used as cross reference between WMO number and ICAO ID.

SEE ALSO

• uacvt
• upairwx
• uacalplt
• upcalc
• ua_parse

For further information about WXP, email technical-support@weather.unisys.com
Last updated by Dan Vietor on August 3, 1998