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NOAA Rapid Update

NWS Storm Prediction Center

Univ. of Wyoming

Center for Atmospheric Research

Unisys

Raw Data

 

Skew-T: Comparing Different Sources

In the overview article Skew-T for the Common Pilot, all of the examples were from one source: NOAA's Rapid Update Cycle. The graphics are excellent, and the interactiveness makes computations easy. There are other presentations for this information, shown here. For consistency, they all display the sounding for Jacksonville, Florida, at 0000Z, 4 January 2017. This sounding shows an interesting amount of convective activity (high CAPE). The raw data that is common to all of these plots is at the end of this article. Look them over. You might decide you prefer a different picture.

Some of these sources are general, some are oriented toward storm-chasers or other enthusiasts. All of them should be considered somewhat experimental, especially the ones that display predictions.

NOAA Rapid Update Cycle

http://rucsoundings.noaa.gov

This is the main source, but with a twist. If you just use the sounding site, the default is one of the observations or forecasts that is interpolated to a grid. Instead of Op40 or Bak40, select RAOBs to get the actual sounding for comparison.

NWS Storm Prediction Center

http://www.spc.noaa.gov/exper/soundings

This site provides a very large graphic image with many subdivisions. If you'd like to see the whole thing at once, click the thumbnail at right and it will pop up in a new window. Be warned, it's bigly.

The graphic has the familiar sounding plot and hodograph, plus a detailed legend that explains and interprets the sounding. These features have been extracted and shown here.

Hodograph. The yellow square in the middle is the mean wind.

Legend and Derived Parameters

University of Wyoming

http://weather.uwyo.edu/upperair/sounding.html

These plots are produced by the university's Department of Atmospheric Science. The site has selectors for sites all over the world. Several displays are available, both GIF and PDF, including the sounding plot and the hodograph.

National Center for Atmospheric Research

http://weather.rap.ucar.edu/upper

Unisys

http://weather.unisys.com/upper_air/skew

Raw Data

All plots in this article were generated from the identical sounding, which is reproduced here. Wind drift, a computation, is not reported as often as the other parameters, which are direct measurements. (OK, pressure altitude in feet (HGHT) is a computation, but it's quick and direct.)

HGHT LEVEL TEMP DWPT WDIR WSPD -------------------------------------------- 30 1010 22 21 328 1000 23 21 230 11 646 989 23 21 1001 977 22 20 235 21 2001 943 20 19 250 33 2096 940 20 18 2552 925 19 17 255 35 2999 910 18 16 260 36 3999 879 17 14 260 35 4925 850 15 12 265 37 6001 818 13 9 265 39 6499 803 12 8 6878 792 11 8 7001 788 11 5 260 42 7051 787 11 4 7402 777 10 6 7934 762 10 2 7999 760 9 2 250 41 8113 757 9 3 8329 751 9 0 8620 743 8 1 8840 737 8 -2 8999 733 8 0 250 43 9098 730 7 0 9321 724 7 -2 9622 716 7 0 10000 706 6 0 240 42 10230 700 5 0 245 41 10461 694 5 -3 10966 681 3 -4 11005 680 3 -5 11163 676 4 -32 11641 664 5 -44 12001 655 4 -44 270 32 12999 631 3 -45 13999 607 0 -42 270 37 15530 573 -3 -37 16001 563 -4 -37 275 46 17687 527 -7 -38 17931 522 -7 -33 17999 521 -7 -31 260 48 18177 517 -7 -23 19029 500 -10 -21 270 45 20000 481 -12 -19 280 48 20372 474 -13 -18 21281 457 -15 -20 22329 438 -17 -23 22999 426 -19 -22 275 62 23241 422 -19 -21 24480 401 -22 -22 24541 400 -22 -22 270 56 25000 392 -23 -24 270 56 25337 387 -24 -25 27999 346 -30 -33 275 48 28123 344 -31 -33 30000 317 -35 -38 300 59 31266 300 -38 -41 305 69 31494 297 -38 -42 33866 267 -45 -47 35302 250 -48 -51 300 82 36001 242 -50 -53 300 88 39993 200 -60 -64 300 98 41574 185 -64 -68 42912 173 -66 -71 43143 171 -65 -70 43378 169 -65 -70 44962 156 -68 -74 305 104 45000 156 -68 -74 305 104 HGHT LEVEL TEMP DWPT WDIR WSPD -------------------------------------------- 45346 153 -69 -75 45735 150 -69 -76 310 96 46401 145 -69 -76 305 79 47516 137 -69 -78 47999 134 -69 -79 285 54 48544 130 -70 -81 48999 127 -70 -82 275 63 49468 124 -70 -83 50000 121 -69 -83 290 69 50782 116 -67 -82 51834 110 -68 -85 52001 109 -68 -85 290 43 53707 100 -70 -88 275 64 54953 94 -71 -89 290 69 55000 94 -71 -89 290 69 55373 92 -71 -89 56001 89 -70 -88 290 35 57085 84 -69 -87 57999 80 -69 -87 295 30 58999 76 -70 -88 275 21 60000 72 -71 -89 250 29 60635 70 -72 -90 60663 70 -72 -90 260 41 61001 69 -71 -89 275 45 62001 65 -70 -88 290 35 62069 65 -70 -88 62860 63 -71 -89 63429 61 -69 -88 63999 59 -69 -88 265 27 64283 58 -69 -88 64762 57 -67 -87 65000 56 -67 -87 275 29 65254 55 -68 -88 65688 54 -65 -86 67001 51 -65 -88 315 15 67257 50 -65 -88 315 14 67999 48 -65 -89 250 14 68494 47 -65 -90 68999 46 -64 -90 245 21 69824 44 -61 -88 70000 44 -61 -89 290 7 71001 42 -62 -90 310 12 72534 39 -63 -93 72999 38 -62 -92 225 18 73999 36 -59 -90 235 25 74191 36 -59 -90 75000 34 -59 -90 275 14 75944 33 -60 -91 77001 31 -58 -90 265 23 77589 30 -58 -90 77657 30 -58 -90 295 20 77999 30 -58 -90 295 19 79989 27 -59 -90 80000 27 -58 -89 265 23 80617 26 -57 -89 81001 26 -56 -88 275 29 82001 24 -56 -88 255 26 82995 23 -55 -87 82999 23 -55 -87 280 28 83999 22 -56 -88 275 26 84776 21 -57 -89 85372 21 -56 -88 86001 20 -56 -88 305 15 86089 20 -57 -89 305 15 87596 19 -57 -89 87999 18 -57 -89 280 31 88999 17 -57 -89 280 25 89960 17 -56 -88