Historical Unidata Internet Data

This script accesses upper air netCDF files from the Historical Unidata Internet Data Distribution (IDD) Global Observational Data archive (ds336.0). It (a) reads raob data from user specified stations; (b) plots a skewT of each sounding; (c) creates a simple text (ascii) file containing mandatory level upper air data. A sample text file (Bermuda_2013030612.ManLevels.txt) follows:

<pre style="margin: 0px; padding: 0px; font-size: 13.3333px; line-height: 12pt; font-family: courier; border-style: solid; border-width: 0px 0px 15px; border-color: transparent; text-indent: 0px; color: rgb(0, 0, 0); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: left; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;"> P HGT T TDEW WSPD WDIR
mb m C C m/s
1011 6 16.2 9.2 5.7 270
1000 131 15.6 7.6 6.7 270
925 786 9.4 5.8 9.3 270
850 1481 4.2 -0.2 11.8 280
700 3039 -2.1 -10.1 14.4 290
500 5640 -19.1 -27.1 24.2 285
400 7260 -29.5 -42.5 35.0 275
300 9260 -42.3 -69.3 55.6 275
250 10470 -51.1 -65.1 58.1 280
200 11910 -54.9 -77.9 62.8 275
150 13730 -57.9 -85.9 51.4 265
100 16250 -64.9 -86.9 26.2 275
70 18400 -64.3 -86.3 24.7 260
50 20460 -63.5 -86.5 13.9 255
99999 99999 99999.0 99999.0 99999.0 99999
[snip]
99999 99999 99999.0 99999.0 99999.0 99999

</pre>

The script will also plot wind barbs for significant wind levels ('sigW') if there are any on the file. In this case, none were available.

NOTE: [1] The units of the time variable ('synTime') contain parentheses. These are non-standard. The script assigns the correct units. [2] The variable 'numSigW' has no attribute which indicates a missing value (ie, missing_value or _FillValue). The script assigns the appripriate _FillValue. A few other variables on the file have missing _FillValue attributes.