Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 260032
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1832 MDT Saturday, April 25, 2015

This forecast is for Sunday, April 26, 2015:

If the trigger temperature of 56.3 F/13.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7137 ft MSL (1830 ft AGL)

Forecast maximum temperature................... 52.0 F/11.6 C
Time of trigger temperature.................... None
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................. 5676 ft MSL (370 ft AGL)
Thermal soaring outlook for Monday 04/27....... 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....................... 20051 ft MSL (14744 ft AGL)
Wave soaring outlook for Monday 04/27.......... Poor

Remarks...

Sunrise/Sunset.................... 06:06:46 / 19:47:35 MDT
Total possible sunshine........... 13 hr 40 min 50 sec (820 min 50 sec)
Altitude of sun at 12:57:21 MDT... 63.82 degrees

Upper air data from numerical model forecast valid on 04/26/2015 at 0600 MDT

Freezing level.................. 10241 ft MSL (4934 ft AGL)
Convective condensation level... 9564 ft MSL (4257 ft AGL)
Lifted condensation level....... 8474 ft MSL (3167 ft AGL)
Lifted index.................... +0.5
K index......................... +22.7

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  -55.4 -67.7   240   27   14   1.1   0.6      M     M       M      M    M
 45000  -53.8 -64.8   230   31   16   1.1   0.6      M     M       M      M    M
 40000  -54.6 -66.3   230   27   14  -0.6  -0.3      M     M       M      M    M
 38000  -55.1 -67.2   220   26   13  -1.7  -0.9      M     M       M      M    M
 36000  -56.2 -69.2   195   29   15  -1.7  -0.9      M     M       M      M    M
 34000  -57.2 -71.0   175   36   19   3.0   1.6      M     M       M      M    M
 32000  -52.3 -62.1   180   36   18   8.1   4.5      M     M       M      M    M
 30000  -46.8 -52.2   185   36   18   9.2   5.0   28.0  82.4    12.7      M    M
 29000  -44.0 -47.2   185   35   18   9.1   5.0   27.6  81.7    12.6      M    M
 28000  -41.3 -42.3   185   33   17   9.1   5.0   27.4  81.3    12.6      M    M
 27000  -38.6 -37.5   180   32   17   9.1   5.0   27.3  81.1    12.6      M    M
 26000  -35.9 -32.6   180   31   16   8.8   4.9   26.9  80.4    12.4      M    M
 25000  -33.3 -27.9   180   29   15   8.8   4.9   26.5  79.7    12.3      M    M
 24000  -30.6 -23.1   180   28   14   8.9   4.9   26.3  79.3    12.2      M    M
 23000  -28.2 -18.8   180   26   14   8.1   4.4   25.7  78.2    11.9      M    M
 22000  -25.7 -14.3   180   25   13   8.1   4.5   25.1  77.1    11.5      M    M
 21000  -23.3  -9.9   175   24   12   7.9   4.3   24.6  76.2    11.2      M    M
 20000  -21.2  -6.2   180   21   11   7.1   3.9   23.6  74.5    10.5      M    M
 19500  -20.1  -4.2   180   19   10   7.1   3.9   23.1  73.6    10.2      M    M
 19000  -19.0  -2.2   180   17    9   7.1   3.9   22.7  72.8     9.9      M    M
 18500  -18.0  -0.4   185   16    8   7.1   3.9   22.3  72.1     9.6      M    M
 18000  -16.8   1.8   185   14    7   8.3   4.6   21.9  71.5     9.3      M    M
 17500  -15.6   3.9   190   13    7   8.3   4.5   21.7  71.0     9.1      M    M
 17000  -14.5   5.9   195   12    6   7.8   4.3   21.4  70.6     8.9      M    M
 16500  -13.4   7.9   200   12    6   7.6   4.2   21.0  69.9     8.5      M    M
 16000  -12.2  10.0   210   11    6   7.5   4.1   20.7  69.2     8.2      M    M
 15500  -10.6  12.9   210   11    5   7.3   4.0   20.1  68.1     7.7      M    M
 15000   -9.6  14.7   210   10    5   7.3   4.0   19.7  67.4     7.4      M    M
 14500   -8.5  16.7   210   10    5   7.2   4.0   19.2  66.6     7.0      M    M
 14000   -7.5  18.5   210   10    5   7.3   4.0   18.8  65.9     6.6      M    M
 13500   -6.4  20.5   205   10    5   7.7   4.2   18.5  65.3     6.3      M    M
 13000   -5.3  22.5   200   10    5   7.7   4.2   18.1  64.7     6.0      M    M
 12500   -4.3  24.3   195   10    5   7.1   3.9   17.7  63.9     5.6      M    M
 12000   -3.2  26.2   195   10    5   7.2   3.9   17.3  63.2     5.2      M    M
 11500   -2.2  28.0   195   10    5   7.1   3.9   16.9  62.4     4.8      M    M
 11000   -1.2  29.8   200    9    5   7.2   3.9   16.5  61.7     4.4      M    M
 10500   -0.3  31.5   200    9    5   4.7   2.6   15.9  60.6     3.8      M    M
 10250    0.0  32.0   200    9    5   5.3   2.9   15.5  59.9     3.4      M    M
 10000    0.4  32.7   200    9    5   6.1   3.4   15.2  59.3     3.1      M    M
  9750    0.9  33.6   200    9    5   6.2   3.4   14.9  58.9     2.8      M    M
  9500    1.3  34.3   200   10    5   5.8   3.2   14.6  58.3     2.5      M    M
  9250    1.7  35.1   195   11    6   6.0   3.3   14.3  57.8     2.2      M    M
  9000    2.1  35.8   195   12    6   5.9   3.2   14.0  57.2     1.9      M    M
  8750    2.6  36.7   190   13    7   6.1   3.4   13.7  56.7     1.6      M    M
  8500    3.0  37.4   190   14    7   6.6   3.6   13.5  56.2     1.3      M    M
  8250    3.5  38.3   185   15    8   6.0   3.3   13.2  55.8     1.1      M    M
  8000    3.9  39.0   180   16    8   8.0   4.4   13.0  55.3     0.8      M    M
  7750    4.6  40.3   180   16    8   7.9   4.3   12.9  55.2     0.7      M    M
  7500    5.0  41.0   175   16    8   5.8   3.2   12.6  54.7     0.4      M    M
  7250    5.4  41.7   175   16    8   6.4   3.5   12.4  54.2     0.1      M    M
  7000    5.9  42.6   170   16    8   6.8   3.7   12.1  53.8    -0.1     81  0.4
  6750    6.4  43.5   165   14    7   5.9   3.3   11.9  53.4    -0.4     60  0.3
  6500    6.7  44.1   160   13    7   5.6   3.1   11.5  52.8    -0.8     42  0.2
  6250    7.1  44.8   150   11    6   3.7   2.0   11.2  52.2    -1.1     23  0.1
  6000    7.2  45.0   145   10    5   1.3   0.7   10.6  51.1    -1.7     12  0.1
  5750    7.2  45.0   130    8    4  -1.7  -0.9    9.9  49.9    -2.4      4  0.0
  5500    6.8  44.2   115    5    3  -9.3  -5.1    8.8  47.8    -3.6      9  0.0

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

           04/26/2015 at 0900 MDT          |       04/26/2015 at 1200 MDT
                                           |
K index... +16.8  LI... +271.9             | K index... +23.0  LI... +272.6
CAPE... +109.5  CIN... -95.8               | CAPE... +162.3  CIN... -14.5
                                           |
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 -55.0 -67.0  240  24 12   0.8   0.4 | -55.3 -67.5  240  22 11   0.9   0.5
 45000 -53.8 -64.8  240  27 14   0.6   0.3 | -53.8 -64.8  240  21 11   0.7   0.4
 40000 -54.7 -66.5  215  21 11  -0.6  -0.4 | -54.7 -66.5  210  21 11  -0.6  -0.3
 38000 -55.2 -67.4  200  21 11  -1.3  -0.7 | -55.4 -67.7  195  22 11  -2.2  -1.2
 36000 -56.0 -68.8  190  25 13  -1.3  -0.7 | -56.7 -70.1  170  24 12  -2.2  -1.2
 34000 -56.8 -70.2  180  28 15   2.4   1.3 | -57.9 -72.2  150  29 15   4.6   2.5
 32000 -52.6 -62.7  185  29 15   7.0   3.9 | -52.4 -62.3  155  30 16   9.3   5.1
 30000 -47.6 -53.7  195  29 15  10.1   5.5 | -46.1 -51.0  155  31 16   9.3   5.1
 29000 -44.7 -48.5  195  28 14   9.8   5.4 | -43.3 -45.9  155  31 16   9.3   5.1
 28000 -41.7 -43.1  195  27 14   9.9   5.4 | -40.5 -40.9  155  30 16   9.3   5.1
 27000 -38.8 -37.8  195  26 13   9.8   5.4 | -37.7 -35.9  155  30 15   9.1   5.0
 26000 -35.9 -32.6  190  26 13   9.6   5.3 | -35.2 -31.4  155  29 15   8.3   4.5
 25000 -33.0 -27.4  185  26 14   9.6   5.3 | -32.7 -26.9  155  27 14   8.3   4.6
 24000 -30.1 -22.2  180  27 14  10.0   5.5 | -30.3 -22.5  160  26 13   8.3   4.6
 23000 -27.9 -18.2  180  26 14   6.4   3.5 | -27.9 -18.2  160  26 13   8.0   4.4
 22000 -26.0 -14.8  180  26 13   6.5   3.6 | -25.5 -13.9  160  27 14   8.0   4.4
 21000 -24.1 -11.4  180  25 13   6.8   3.7 | -23.2  -9.8  160  28 14   8.0   4.4
 20000 -22.0  -7.6  180  25 13   7.5   4.1 | -20.8  -5.4  155  29 15   7.9   4.3
 19500 -20.9  -5.6  180  25 13   7.5   4.1 | -19.7  -3.5  155  30 16   7.9   4.3
 19000 -19.8  -3.6  180  25 13   7.5   4.1 | -18.5  -1.3  150  31 16   7.9   4.3
 18500 -18.7  -1.7  180  25 13   7.6   4.1 | -17.3   0.9  150  32 16   7.9   4.3
 18000 -17.4   0.7  180  25 13   8.7   4.8 | -16.3   2.7  150  32 16   7.0   3.9
 17500 -16.2   2.8  180  25 13   8.7   4.8 | -15.2   4.6  145  31 16   7.1   3.9
 17000 -14.9   5.2  180  25 13   8.0   4.4 | -14.2   6.4  140  30 16   6.6   3.6
 16500 -13.7   7.3  180  24 12   7.8   4.3 | -13.2   8.2  140  29 15   6.4   3.5
 16000 -12.6   9.3  180  23 12   7.9   4.3 | -11.8  10.8  140  27 14   6.2   3.4
 15500 -10.7  12.7  180  22 11   8.2   4.5 | -10.9  12.4  140  24 12   6.2   3.4
 15000  -9.5  14.9  185  21 11   8.1   4.5 | -10.0  14.0  145  22 11   6.2   3.4
 14500  -8.3  17.1  180  20 10   8.0   4.4 |  -9.1  15.6  145  21 11   6.2   3.4
 14000  -7.1  19.2  180  19 10   7.8   4.3 |  -8.2  17.2  150  21 11   6.2   3.4
 13500  -6.0  21.2  180  18  9   7.3   4.0 |  -7.3  18.9  150  21 11   6.4   3.5
 13000  -4.9  23.2  180  17  9   7.4   4.0 |  -6.4  20.5  150  22 11   6.3   3.4
 12500  -3.9  25.0  180  16  8   7.5   4.1 |  -5.5  22.1  150  21 11   5.7   3.1
 12000  -2.8  27.0  180  15  8   7.6   4.1 |  -4.7  23.5  155  19 10   5.7   3.2
 11500  -1.8  28.8  180  14  7   6.9   3.8 |  -3.8  25.2  160  17  9   6.0   3.3
 11000  -0.9  30.4  185  12  6   6.9   3.8 |  -3.0  26.6  160  15  8   5.9   3.2
 10500  -0.0  32.0  185  10  5   5.2   2.8 |  -2.2  28.0  165  13  6   4.9   2.7
 10250   0.3  32.5  185   9  4   5.2   2.9 |  -1.8  28.8  165  12  6   5.3   2.9
 10000   0.7  33.3  185   8  4   4.4   2.4 |  -1.4  29.5  170  11  5   7.3   4.0
  9750   0.9  33.6  185   7  3   4.5   2.5 |  -0.8  30.6  165   9  5   8.3   4.5
  9500   1.3  34.3  185   7  3   5.0   2.7 |  -0.2  31.6  165   8  4   7.9   4.3
  9250   1.6  34.9  185   7  3   5.0   2.7 |   0.3  32.5  155   7  3   8.2   4.5
  9000   2.0  35.6  190   7  3   4.5   2.4 |   0.9  33.6  150   6  3   7.7   4.2
  8750   2.2  36.0  185   7  4   4.3   2.4 |   1.5  34.7  150   5  3   8.6   4.7
  8500   2.6  36.7  185   8  4   5.0   2.8 |   2.1  35.8  140   5  3   9.7   5.3
  8250   2.9  37.2  185   8  4   4.2   2.3 |   2.8  37.0  135   5  2   9.3   5.1
  8000   3.2  37.8  185   9  5   6.7   3.7 |   3.5  38.3  125   4  2  11.1   6.1
  7750   3.8  38.8  185  10  5   7.9   4.3 |   4.3  39.7  125   4  2  10.6   5.8
  7500   4.3  39.7  180  10  5   6.3   3.5 |   5.0  41.0  125   4  2   8.5   4.7
  7250   4.8  40.6  180  10  5   6.6   3.6 |   5.7  42.3  125   4  2   9.7   5.3
  7000   5.2  41.4  180   9  5   6.1   3.3 |   6.4  43.5  120   4  2  11.1   6.1
  6750   5.6  42.1  180   8  4   4.0   2.2 |   7.2  45.0  120   3  2  10.1   5.5
  6500   5.7  42.3  180   6  3   1.3   0.7 |   7.9  46.2  120   3  2   8.4   4.6
  6250   5.9  42.6  180   4  2   5.6   3.1 |   8.6  47.5  120   3  1  10.1   5.5
  6000   6.5  43.7  175   3  2  10.6   5.8 |   9.4  48.9  120   3  1  11.6   6.4
  5750   7.2  45.0  165   2  1   9.0   4.9 |  10.2  50.4  115   3  1  10.0   5.5
  5500   8.0  46.4  140   1  0  12.8   7.0 |  11.0  51.8  110   2  1  11.4   6.3

           04/26/2015 at 1500 MDT          |       04/26/2015 at 1800 MDT
                                           |
K index... +25.1  LI... +271.5             | K index... +23.1  LI... +271.9
CAPE... +473.2  CIN... M                   | CAPE... +308.4  CIN... -0.5
                                           |
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 -55.4 -67.7  245  16  8   0.7   0.4 | -55.8 -68.4  265  12  6   0.4   0.2
 45000 -54.3 -65.7  240  13  7   0.4   0.2 | -55.2 -67.4  245  10  5   0.1   0.1
 40000 -55.8 -68.4  210  13  7  -1.0  -0.6 | -56.2 -69.2  185   4  2  -0.7  -0.4
 38000 -56.4 -69.5  190  13  7  -0.9  -0.5 | -56.5 -69.7  135   6  3  -0.4  -0.2
 36000 -56.9 -70.4  150  16  8  -0.9  -0.5 | -56.8 -70.2  115  13  7  -0.4  -0.2
 34000 -57.3 -71.1  135  22 12   5.9   3.2 | -56.8 -70.2  110  20 10   6.2   3.4
 32000 -51.1 -60.0  140  24 13   9.1   5.0 | -51.0 -59.8  120  20 11   8.6   4.7
 30000 -45.7 -50.3  145  26 13   9.3   5.1 | -45.8 -50.4  125  21 11   9.2   5.1
 29000 -42.9 -45.2  145  26 14   9.4   5.1 | -43.0 -45.4  125  21 11   9.3   5.1
 28000 -40.1 -40.2  150  27 14   9.4   5.1 | -40.2 -40.4  120  21 11   9.3   5.1
 27000 -37.3 -35.1  150  27 14   9.2   5.0 | -37.4 -35.3  120  21 11   9.1   5.0
 26000 -34.7 -30.5  150  28 14   8.6   4.7 | -34.8 -30.6  120  20 10   8.7   4.8
 25000 -32.1 -25.8  150  29 15   8.6   4.7 | -32.2 -26.0  120  20 10   8.7   4.8
 24000 -29.6 -21.3  150  29 15   8.7   4.8 | -29.6 -21.3  120  19 10   8.7   4.8
 23000 -27.2 -17.0  150  31 16   7.9   4.4 | -27.3 -17.1  120  19 10   7.8   4.3
 22000 -24.8 -12.6  150  33 17   8.0   4.4 | -25.0 -13.0  125  19 10   7.8   4.3
 21000 -22.5  -8.5  150  35 18   7.8   4.3 | -22.7  -8.9  130  19 10   7.7   4.2
 20000 -20.2  -4.4  150  35 18   7.5   4.1 | -20.5  -4.9  135  21 11   7.5   4.1
 19500 -19.1  -2.4  150  35 18   7.5   4.1 | -19.4  -2.9  135  21 11   7.5   4.1
 19000 -18.0  -0.4  150  36 18   7.5   4.1 | -18.2  -0.8  135  22 11   7.5   4.1
 18500 -16.9   1.6  145  36 19   7.4   4.1 | -17.1   1.2  140  22 12   7.4   4.1
 18000 -15.9   3.4  145  36 18   6.4   3.5 | -16.1   3.0  140  23 12   6.6   3.6
 17500 -15.0   5.0  145  35 18   6.5   3.5 | -15.1   4.8  145  24 12   6.6   3.6
 17000 -14.0   6.8  140  35 18   6.6   3.6 | -14.1   6.6  145  25 13   7.1   3.9
 16500 -12.6   9.3  135  34 17   6.7   3.7 | -12.5   9.5  145  25 13   7.2   3.9
 16000 -11.6  11.1  135  33 17   6.4   3.5 | -11.5  11.3  145  26 13   7.3   4.0
 15500 -10.7  12.7  130  31 16   6.4   3.5 | -10.4  13.3  145  26 13   7.4   4.0
 15000  -9.7  14.5  130  29 15   6.3   3.4 |  -9.3  15.3  145  26 13   7.0   3.8
 14500  -8.8  16.2  125  27 14   6.2   3.4 |  -8.4  16.9  145  25 13   6.8   3.7
 14000  -7.9  17.8  125  24 12   5.9   3.3 |  -7.4  18.7  145  24 12   6.6   3.6
 13500  -7.1  19.2  120  21 11   5.4   3.0 |  -6.5  20.3  145  21 11   6.4   3.5
 13000  -6.3  20.7  115  19 10   5.5   3.0 |  -5.6  21.9  140  19 10   6.3   3.4
 12500  -5.5  22.1  110  16  8   6.0   3.3 |  -4.7  23.5  135  17  9   5.9   3.2
 12000  -4.6  23.7  110  14  7   6.0   3.3 |  -3.9  25.0  125  15  8   5.7   3.1
 11500  -3.8  25.2  100  12  6   6.2   3.4 |  -3.1  26.4  115  14  7   4.7   2.6
 11000  -2.9  26.8  090  11  6   6.2   3.4 |  -2.5  27.5  100  13  7   4.7   2.6
 10500  -2.0  28.4  090  11  6   5.9   3.2 |  -1.8  28.8  095  12  6   4.5   2.5
 10250  -1.6  29.1  090  11  6   6.6   3.6 |  -1.5  29.3  090  11  6   4.8   2.6
 10000  -1.0  30.2  090  11  5   9.0   4.9 |  -1.1  30.0  090  11  6   6.6   3.6
  9750  -0.4  31.3  090  11  5   8.7   4.8 |  -0.5  31.1  095  11  5   7.3   4.0
  9500   0.2  32.4  090  10  5   7.4   4.1 |  -0.1  31.8  095  10  5   6.8   3.7
  9250   0.8  33.4  085  10  5   8.1   4.4 |   0.4  32.7  100  10  5   6.8   3.7
  9000   1.3  34.3  085  10  5   6.9   3.8 |   0.9  33.6  105  10  5   7.2   4.0
  8750   1.8  35.2  085  10  5   7.2   3.9 |   1.4  34.5  110  10  5   7.5   4.1
  8500   2.4  36.3  085   9  5   8.4   4.6 |   2.0  35.6  110  11  5   7.2   4.0
  8250   2.9  37.2  080   9  5   8.1   4.4 |   2.5  36.5  110  11  6   7.4   4.0
  8000   3.5  38.3  080   9  4   9.0   5.0 |   3.0  37.4  110  11  6   7.5   4.1
  7750   4.2  39.6  075   8  4   8.7   4.8 |   3.5  38.3  105  12  6   7.1   3.9
  7500   4.8  40.6  075   8  4   7.5   4.1 |   4.0  39.2  100  12  6   6.4   3.5
  7250   5.3  41.5  070   7  4   8.5   4.7 |   4.5  40.1  100  12  6   7.3   4.0
  7000   6.0  42.8  070   7  3  10.3   5.7 |   5.1  41.2  095  11  6   8.7   4.8
  6750   6.7  44.1  065   6  3   9.6   5.3 |   5.7  42.3  095  11  6   8.7   4.8
  6500   7.4  45.3  060   6  3   8.1   4.5 |   6.3  43.3  090  10  5   8.4   4.6
  6250   8.0  46.4  055   5  3   9.9   5.5 |   6.9  44.4  090  10  5   9.5   5.2
  6000   8.8  47.8  050   5  3  11.6   6.3 |   7.7  45.9  090  10  5  10.3   5.7
  5750   9.6  49.3  045   5  2  10.0   5.5 |   8.4  47.1  090   9  5   9.9   5.5
  5500  10.4  50.7  040   4  2  11.1   6.1 |   9.2  48.6  085   9  4  11.3   6.2
________________________________________________________________________________

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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