Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 181325
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0725 MDT Monday, May 18, 2015

This forecast is for Monday, May 18, 2015:

If the trigger temperature of 53.8 F/12.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 10174 ft MSL (4889 ft AGL)

Forecast maximum temperature................... 58.0 F/14.9 C
Time of trigger temperature.................... 1315 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8902 ft MSL (3617 ft AGL)
Thermal soaring outlook for Tuesday 05/19...... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 14638 ft MSL (9353 ft AGL)
Wave soaring outlook for Tuesday 05/19......... Poor

Remarks... None

Sunrise/Sunset.................... 05:42:33 / 20:09:05 MDT
Total possible sunshine........... 14 hr 26 min 32 sec (866 min 32 sec)
Altitude of sun at 12:56:01 MDT... 69.82 degrees

Upper air data from rawinsonde observation taken on 05/18/2015 at 0600 MDT

Freezing level.................. 9423 ft MSL (4138 ft AGL)
Convective condensation level... 11083 ft MSL (5798 ft AGL)
Lifted condensation level....... 10558 ft MSL (5272 ft AGL)
Lifted index.................... +2.8
K index......................... +24.5

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -60.0 -76.0   230   22   11   6.9   3.8   99.3 210.8    48.6      M    M
 45000  -56.0 -68.8   230   46   23  -2.2  -1.2   80.2 176.3    40.4      M    M
 40000  -58.0 -72.4   245   56   29  -7.9  -4.3   54.3 129.7    26.2      M    M
 38000  -57.5 -71.5   230   39   20   6.1   3.4   46.1 115.0    21.4      M    M
 36000  -54.8 -66.6   240   46   24   4.4   2.4   41.3 106.3    18.7      M    M
 34000  -52.0 -61.6   245   46   24   7.9   4.4   37.0  98.6    16.1      M    M
 32000  -47.3 -53.1   240   41   21   8.0   4.4   35.6  96.1    15.5      M    M
 30000  -41.8 -43.2   240   36   18   8.3   4.6   34.1  93.3    14.8      M    M
 29000  -39.1 -38.4   240   35   18   9.2   5.0   33.9  93.0    14.8      M    M
 28000  -36.4 -33.5   240   33   17   8.7   4.8   33.6  92.4    14.7      M    M
 27000  -33.9 -29.0   245   32   17   8.2   4.5   33.1  91.5    14.5      M    M
 26000  -31.4 -24.5   245   31   16   8.0   4.4   32.4  90.4    14.2      M    M
 25000  -29.7 -21.5   245   30   15   6.6   3.6   31.0  87.8    13.2      M    M
 24000  -27.2 -17.0   215   24   12   7.6   4.2   30.4  86.8    12.8      M    M
 23000  -24.9 -12.8   215   24   12   7.7   4.2   29.6  85.2    12.2      M    M
 22000  -22.6  -8.7   220   24   12   7.8   4.3   28.8  83.9    11.8      M    M
 21000  -20.3  -4.5   220   24   12   7.8   4.3   28.2  82.8    11.3      M    M
 20000  -18.2  -0.8   220   24   12   7.1   3.9   27.4  81.4    10.8      M    M
 19500  -17.1   1.2   220   23   12   7.1   3.9   26.9  80.5    10.4      M    M
 19000  -16.1   3.0   220   22   11   7.0   3.9   26.5  79.7    10.0      M    M
 18500  -15.2   4.6   220   21   11   4.7   2.6   25.8  78.4     9.5      M    M
 18000  -14.5   5.9   225   20   10   5.1   2.8   24.9  76.8     8.8      M    M
 17500  -13.8   7.2   230   18    9   7.8   4.3   24.1  75.4     8.1      M    M
 17000  -12.1  10.2   235   17    9   9.6   5.2   24.5  76.1     8.4      M    M
 16500  -11.1  12.0   240   16    8   6.9   3.8   23.9  75.1     8.0      M    M
 16000  -10.1  13.8   250   15    8   6.2   3.4   23.4  74.2     7.5      M    M
 15500   -9.3  15.3   245   15    8   5.7   3.2   22.8  73.0     6.9      M    M
 15000   -8.0  17.6   240   16    8   5.7   3.1   21.7  71.1     6.0      M    M
 14500   -7.2  19.0   240   17    9   5.7   3.1   21.1  70.0     5.5      M    M
 14000   -6.4  20.5   235   17    9   5.7   3.2   20.5  68.9     4.9      M    M
 13500   -5.5  22.1   235   14    7   5.8   3.2   19.8  67.6     4.3      M    M
 13000   -4.7  23.5   235   12    6   5.8   3.2   19.1  66.4     3.7      M    M
 12500   -3.9  25.0   235   10    5   5.8   3.2   18.5  65.3     3.1      M    M
 12000   -3.0  26.6   235    8    4   5.8   3.2   17.9  64.2     2.5      M    M
 11500   -2.2  28.0   220    8    4   5.8   3.2   17.2  63.0     1.8      M    M
 11000   -1.2  29.8   210    8    4  12.4   6.8   16.8  62.2     1.4      M    M
 10500   -0.3  31.5   200    9    5  -1.8  -1.0   16.2  61.2     0.8      M    M
 10250   -0.3  31.5   195    9    5   0.6   0.3   15.4  59.8     0.1      M    M
 10000   -0.3  31.5   200    8    4  -0.2  -0.1   14.7  58.4    -0.6    312  1.6
  9750   -0.3  31.5   205    8    4   1.9   1.0   13.9  57.1    -1.3    304  1.5
  9500   -0.0  32.0   205    8    4   3.5   1.9   13.4  56.2    -1.8    289  1.5
  9250    0.2  32.4   210    7    4   3.0   1.7   12.9  55.2    -2.3    275  1.4
  9000    0.4  32.7   215    7    4   3.2   1.7   12.4  54.3    -2.8    261  1.3
  8750    0.6  33.1   195    6    3   3.1   1.7   11.9  53.4    -3.4    246  1.3
  8500    0.9  33.6   170    5    3   3.1   1.7   11.4  52.4    -3.9    232  1.2
  8250    1.1  34.0   145    6    3   3.1   1.7   10.8  51.5    -4.4    218  1.1
  8000    1.3  34.3   130    7    4   3.1   1.7   10.3  50.6    -4.9    203  1.0
  7750    1.6  34.9   120    7    4   3.2   1.7    9.8  49.7    -5.4    189  1.0
  7500    1.8  35.2   110    7    4   3.1   1.7    9.3  48.8    -5.9    175  0.9
  7250    2.0  35.6   100    7    4   3.4   1.9    8.8  47.8    -6.4    160  0.8
  7000    2.4  36.3   090    8    4   6.8   3.7    8.4  47.2    -6.8    143  0.7
  6750    3.0  37.4   085    8    4   8.9   4.9    8.3  47.0    -6.9    116  0.6
  6500    3.7  38.7   075    8    4   8.3   4.6    8.2  46.8    -7.1     90  0.5
  6250    4.3  39.7   070    8    4   8.5   4.7    8.1  46.6    -7.2     63  0.3
  6000    4.9  40.8   060    8    4   8.4   4.6    8.0  46.5    -7.3     37  0.2
  5750    5.6  42.1   050    7    4   8.7   4.8    7.9  46.3    -7.4     11  0.1
  5500    6.2  43.2   030    7    4  10.3   5.7    7.9  46.2    -7.5      M    M

 * * * * * * Numerical weather prediction model forecast data valid * * * * * *

           05/18/2015 at 0900 MDT          |       05/18/2015 at 1200 MDT
                                           |
K index... +20.5  LI... +274.1             | K index... +22.7  LI... +275.5
CAPE... 0.0  CIN... -0.0                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.2 -71.0  230  28 15   1.0   0.5 | -58.0 -72.4  230  27 14   0.8   0.5
 45000 -56.0 -68.8  220  39 20  -1.4  -0.8 | -57.0 -70.6  230  40 20  -0.9  -0.5
 40000 -58.1 -72.6  240  50 26  -1.3  -0.7 | -58.3 -72.9  235  56 29  -0.9  -0.5
 38000 -56.6 -69.9  245  51 26   4.0   2.2 | -57.1 -70.8  235  56 29   3.4   1.8
 36000 -54.2 -65.6  245  50 26   4.0   2.2 | -55.1 -67.2  235  54 28   3.3   1.8
 34000 -50.5 -58.9  250  47 24   7.6   4.2 | -51.4 -60.5  235  50 26   8.4   4.6
 32000 -46.0 -50.8  250  41 21   7.6   4.2 | -46.4 -51.5  240  45 23   8.4   4.6
 30000 -41.2 -42.2  250  35 18   8.3   4.6 | -41.2 -42.2  240  40 21   8.7   4.8
 29000 -38.7 -37.7  250  33 17   8.3   4.6 | -38.6 -37.5  240  38 19   8.7   4.8
 28000 -36.2 -33.2  250  30 16   8.3   4.5 | -36.0 -32.8  245  35 18   8.7   4.8
 27000 -33.8 -28.8  245  28 15   7.7   4.2 | -33.5 -28.3  245  33 17   8.1   4.5
 26000 -31.5 -24.7  245  26 14   7.7   4.2 | -31.0 -23.8  240  31 16   8.1   4.5
 25000 -29.2 -20.6  245  24 13   7.8   4.3 | -28.6 -19.5  240  29 15   8.2   4.5
 24000 -26.9 -16.4  245  23 12   7.3   4.0 | -26.2 -15.2  240  26 14   7.1   3.9
 23000 -24.7 -12.5  245  21 11   7.4   4.0 | -24.1 -11.4  235  24 12   7.3   4.0
 22000 -22.5  -8.5  245  20 10   7.4   4.0 | -21.9  -7.4  225  21 11   7.4   4.1
 21000 -20.5  -4.9  245  19 10   6.2   3.4 | -19.8  -3.6  220  20 10   7.1   3.9
 20000 -18.7  -1.7  245  19 10   6.3   3.4 | -17.7   0.1  220  19 10   7.2   3.9
 19500 -17.7   0.1  245  19 10   6.3   3.5 | -16.7   1.9  215  18  9   7.2   3.9
 19000 -16.8   1.8  245  19 10   6.3   3.5 | -15.6   3.9  215  18  9   7.2   4.0
 18500 -15.8   3.6  245  19 10   8.1   4.4 | -14.6   5.7  215  17  9   7.1   3.9
 18000 -14.6   5.7  245  20 10   8.0   4.4 | -13.5   7.7  210  15  8   7.2   3.9
 17500 -13.4   7.9  245  20 10   7.4   4.1 | -12.1  10.2  210  14  7   6.2   3.4
 17000 -11.8  10.8  245  22 11   7.2   3.9 | -11.2  11.8  210  14  7   6.2   3.4
 16500 -10.8  12.6  240  23 12   6.9   3.8 | -10.2  13.6  210  13  7   6.6   3.6
 16000  -9.8  14.4  240  24 12   6.9   3.8 |  -9.2  15.4  210  13  7   6.7   3.7
 15500  -8.8  16.2  235  24 13   6.7   3.7 |  -8.3  17.1  205  13  7   6.3   3.5
 15000  -7.8  18.0  235  25 13   6.6   3.6 |  -7.4  18.7  210  14  7   5.9   3.2
 14500  -6.9  19.6  230  25 13   6.5   3.6 |  -6.5  20.3  210  14  7   5.7   3.1
 14000  -6.0  21.2  225  25 13   6.1   3.4 |  -5.8  21.6  210  15  7   4.9   2.7
 13500  -5.1  22.8  225  25 13   6.2   3.4 |  -5.1  22.8  210  15  8   4.9   2.7
 13000  -4.3  24.3  220  24 12   5.7   3.1 |  -4.4  24.1  210  16  8   4.9   2.7
 12500  -3.5  25.7  220  23 12   5.8   3.2 |  -3.7  25.3  205  16  8   4.9   2.7
 12000  -2.7  27.1  215  21 11   4.5   2.5 |  -3.0  26.6  200  17  9   4.4   2.4
 11500  -2.1  28.2  215  20 10   4.7   2.6 |  -2.4  27.7  200  17  9   4.4   2.4
 11000  -1.6  29.1  215  18  9   2.1   1.2 |  -1.8  28.8  195  17  9   4.2   2.3
 10500  -1.3  29.7  215  15  8   2.5   1.3 |  -1.1  30.0  195  17  9   4.2   2.3
 10250  -1.1  30.0  220  14  7   3.3   1.8 |  -0.9  30.4  195  17  9   3.1   1.7
 10000  -0.8  30.6  220  13  7   4.0   2.2 |  -0.7  30.7  195  17  9   3.7   2.0
  9750  -0.5  31.1  215  12  6   4.3   2.3 |  -0.3  31.5  195  17  9   5.4   3.0
  9500  -0.2  31.6  215  11  5   4.2   2.3 |   0.1  32.2  190  17  9   4.8   2.6
  9250   0.1  32.2  210  10  5   3.9   2.1 |   0.4  32.7  190  16  8   3.6   2.0
  9000   0.4  32.7  200   9  4   3.7   2.0 |   0.6  33.1  190  15  8   3.5   1.9
  8750   0.6  33.1  185   8  4   3.6   2.0 |   0.9  33.6  185  14  7   4.7   2.6
  8500   0.8  33.4  170   8  4   2.3   1.2 |   1.2  34.2  180  13  7   3.6   2.0
  8250   1.0  33.8  150   8  4   1.2   0.7 |   1.4  34.5  175  12  6   2.1   1.2
  8000   1.1  34.0  130   8  4   1.5   0.8 |   1.6  34.9  165  11  6   2.4   1.3
  7750   1.2  34.2  115   9  5   0.6   0.3 |   1.7  35.1  155  10  5   0.5   0.3
  7500   1.2  34.2  110   9  5   2.7   1.5 |   1.8  35.2  145   9  5   4.1   2.2
  7250   1.6  34.9  105  10  5   5.1   2.8 |   2.3  36.1  135   8  4   8.1   4.5
  7000   1.9  35.4  100  11  5   3.9   2.1 |   2.8  37.0  120   8  4   6.8   3.7
  6750   2.2  36.0  095  11  6   7.7   4.2 |   3.4  38.1  105   7  4   8.2   4.5
  6500   3.0  37.4  095  10  5  10.8   5.9 |   4.0  39.2  100   7  4   9.5   5.2
  6250   3.7  38.7  095  10  5   9.9   5.5 |   4.7  40.5  100   7  3   8.9   4.9
  6000   4.4  39.9  090   9  5  10.2   5.6 |   5.4  41.7  095   6  3  10.1   5.6
  5750   5.2  41.4  090   9  5  12.1   6.6 |   6.2  43.2  090   6  3  12.9   7.1
  5500   6.2  43.2  090   8  4  15.5   8.5 |   7.2  45.0  090   6  3  14.0   7.7

           05/18/2015 at 1500 MDT          |       05/18/2015 at 1800 MDT
                                           |
K index... +8.0  LI... +274.0              | K index... +22.6  LI... +272.5
CAPE... +40.9  CIN... -9.2                 | CAPE... +103.7  CIN... -2.8
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.2 -71.0  235  28 14   0.8   0.4 | -57.0 -70.6  235  25 13   0.8   0.5
 45000 -56.3 -69.3  240  39 20  -1.0  -0.6 | -56.2 -69.2  240  39 20  -2.6  -1.4
 40000 -57.9 -72.2  240  61 31  -1.0  -0.5 | -60.2 -76.4  245  64 33  -2.5  -1.4
 38000 -56.7 -70.1  240  62 32   3.1   1.7 | -58.6 -73.5  245  63 33   4.7   2.6
 36000 -54.9 -66.8  240  60 31   3.1   1.7 | -55.8 -68.4  245  58 30   4.7   2.6
 34000 -51.4 -60.5  240  56 29   8.0   4.4 | -51.4 -60.5  245  54 28   8.9   4.9
 32000 -46.6 -51.9  240  50 26   8.0   4.4 | -46.0 -50.8  240  50 26   8.9   4.9
 30000 -41.4 -42.5  235  47 24   9.1   5.0 | -40.6 -41.1  240  48 25   9.0   5.0
 29000 -38.7 -37.7  235  46 24   9.1   5.0 | -37.9 -36.2  240  48 25   9.0   5.0
 28000 -36.0 -32.8  235  46 24   9.1   5.0 | -35.2 -31.4  235  47 24   9.0   5.0
 27000 -33.4 -28.1  235  44 23   8.2   4.5 | -32.6 -26.7  235  46 24   8.2   4.5
 26000 -30.9 -23.6  235  41 21   8.1   4.5 | -30.2 -22.4  235  44 23   8.2   4.5
 25000 -28.5 -19.3  235  39 20   8.1   4.5 | -27.7 -17.9  235  43 22   8.2   4.5
 24000 -26.1 -15.0  235  36 18   7.2   4.0 | -25.4 -13.7  235  41 21   7.2   3.9
 23000 -24.0 -11.2  235  33 17   7.3   4.0 | -23.2  -9.8  230  38 19   7.3   4.0
 22000 -21.8  -7.2  235  30 15   7.3   4.0 | -21.1  -6.0  230  34 18   7.3   4.0
 21000 -19.5  -3.1  235  27 14   7.9   4.3 | -18.9  -2.0  225  32 16   7.2   3.9
 20000 -17.2   1.0  235  25 13   7.9   4.3 | -16.8   1.8  220  29 15   7.2   3.9
 19500 -16.0   3.2  235  25 13   7.9   4.3 | -15.8   3.6  220  28 15   7.2   3.9
 19000 -14.8   5.4  235  24 12   7.7   4.2 | -14.7   5.5  215  27 14   7.2   3.9
 18500 -13.8   7.2  230  23 12   5.5   3.0 | -13.8   7.2  215  27 14   5.4   3.0
 18000 -13.0   8.6  225  23 12   5.7   3.1 | -13.0   8.6  215  26 14   5.6   3.0
 17500 -11.7  10.9  225  22 11   5.8   3.2 | -12.1  10.2  210  26 13   6.7   3.7
 17000 -10.8  12.6  225  21 11   5.6   3.1 | -10.5  13.1  210  26 13   7.3   4.0
 16500  -9.8  14.4  230  19 10   7.7   4.2 |  -9.5  14.9  205  25 13   6.1   3.4
 16000  -8.6  16.5  230  19 10   7.9   4.4 |  -8.6  16.5  205  25 13   6.0   3.3
 15500  -7.5  18.5  230  19 10   7.5   4.1 |  -7.8  18.0  200  24 12   6.3   3.5
 15000  -6.4  20.5  230  18  9   7.1   3.9 |  -6.8  19.8  200  23 12   6.7   3.7
 14500  -5.4  22.3  230  17  9   7.3   4.0 |  -5.8  21.6  195  22 12   6.7   3.7
 14000  -4.3  24.3  230  17  9   7.7   4.2 |  -4.8  23.4  195  22 11   6.6   3.6
 13500  -3.2  26.2  225  18  9   7.6   4.2 |  -3.8  25.2  190  22 11   6.6   3.6
 13000  -2.2  28.0  225  18  9   6.7   3.7 |  -3.0  26.6  190  22 11   5.5   3.0
 12500  -1.2  29.8  220  19 10   6.8   3.7 |  -2.2  28.0  190  23 12   5.7   3.1
 12000  -0.6  30.9  215  19 10   3.3   1.8 |  -1.4  29.5  185  24 12   5.1   2.8
 11500  -0.1  31.8  210  20 10   3.8   2.1 |  -0.7  30.7  185  25 13   5.2   2.8
 11000   0.1  32.2  205  21 11   0.2   0.1 |   0.1  32.2  180  25 13   5.9   3.3
 10500   0.0  32.0  195  22 11   0.8   0.4 |   0.9  33.6  170  23 12   5.8   3.2
 10250   0.0  32.0  190  23 12  -0.1  -0.1 |   1.2  34.2  170  22 12   2.5   1.4
 10000   0.1  32.2  190  23 12   4.7   2.6 |   1.4  34.5  165  22 11   6.6   3.6
  9750   0.7  33.3  180  23 12   9.4   5.2 |   2.2  36.0  165  21 11  12.1   6.6
  9500   1.3  34.3  175  22 12   7.6   4.2 |   3.0  37.4  160  19 10  10.3   5.7
  9250   1.8  35.2  170  22 11   5.9   3.2 |   3.7  38.7  160  18  9   8.4   4.6
  9000   2.2  36.0  165  20 10   6.4   3.5 |   4.3  39.7  155  18  9   9.0   4.9
  8750   2.7  36.9  160  19 10   9.4   5.1 |   5.0  41.0  155  18  9  11.8   6.5
  8500   3.4  38.1  155  17  9   8.7   4.8 |   5.9  42.6  155  17  9  10.7   5.9
  8250   3.9  39.0  145  15  8   7.1   3.9 |   6.6  43.9  155  17  9   9.2   5.0
  8000   4.5  40.1  140  14  7   7.6   4.1 |   7.3  45.1  155  16  8   9.2   5.0
  7750   5.1  41.2  135  13  7   9.2   5.1 |   8.0  46.4  155  15  8  10.0   5.5
  7500   5.8  42.4  130  12  6  10.0   5.5 |   8.7  47.7  155  14  7   9.3   5.1
  7250   6.5  43.7  130  11  6   9.5   5.2 |   9.3  48.7  155  14  7   8.5   4.6
  7000   7.2  45.0  125  11  6   9.7   5.3 |  10.0  50.0  150  13  7   8.7   4.8
  6750   7.9  46.2  125  10  5  10.2   5.6 |  10.6  51.1  150  12  6   9.6   5.3
  6500   8.7  47.7  120  10  5  10.4   5.7 |  11.4  52.5  150  11  5   9.9   5.5
  6250   9.5  49.1  120   9  5  10.1   5.6 |  12.1  53.8  150  10  5   9.6   5.3
  6000  10.2  50.4  120   9  4  10.5   5.8 |  12.8  55.0  150   9  4   9.5   5.2
  5750  11.1  52.0  115   8  4  14.8   8.1 |  13.5  56.3  145   8  4  10.3   5.6
  5500  12.4  54.3  115   8  4  20.9  11.5 |  14.3  57.7  145   6  3  12.3   6.8
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613


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