Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 160022
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1820 MDT Wednesday, April 15, 2015

This forecast is for Thursday, April 16, 2015:

If the trigger temperature of 47.6 F/8.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8081 ft MSL (2774 ft AGL)

Forecast maximum temperature................... 43.0 F/6.6 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................. 5750 ft MSL (443 ft AGL)
Thermal soaring outlook for Friday 04/17....... 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....................... 18080 ft MSL (12773 ft AGL)
Wave soaring outlook for Friday 04/17.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:20:49 / 19:37:31 MDT
Total possible sunshine........... 13 hr 16 min 43 sec (796 min 43 sec)
Altitude of sun at 12:59:19 MDT... 60.44 degrees

Upper air data from numerical model forecast valid on 04/16/2015 at 0600 MDT

Freezing level.................. 6886 ft MSL (1579 ft AGL)
Convective condensation level... 12296 ft MSL (6989 ft AGL)
Lifted condensation level....... 9538 ft MSL (4232 ft AGL)
Lifted index.................... +5.7
K index......................... +16.8

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  -57.0 -70.6   240   14    7   3.2   1.7      M     M       M      M    M
 45000  -52.2 -62.0   245   20   11   3.1   1.7      M     M       M      M    M
 40000  -47.8 -54.0   230   20   10   2.8   1.5      M     M       M      M    M
 38000  -46.9 -52.4   225   24   12  -0.5  -0.3      M     M       M      M    M
 36000  -47.2 -53.0   220   32   16  -0.5  -0.3      M     M       M      M    M
 34000  -47.5 -53.5   220   40   20  -0.7  -0.4      M     M       M      M    M
 32000  -48.1 -54.6   215   51   26  -1.1  -0.6      M     M       M      M    M
 30000  -48.8 -55.8   215   62   32   1.5   0.8      M     M       M      M    M
 29000  -46.6 -51.9   210   59   31   6.1   3.4   25.6  78.0    14.8      M    M
 28000  -44.8 -48.6   210   57   30   6.1   3.4   24.1  75.5    13.8      M    M
 27000  -43.0 -45.4   205   56   29   5.9   3.2   22.9  73.2    13.0      M    M
 26000  -40.5 -40.9   200   52   27   9.0   4.9   22.3  72.1    12.7      M    M
 25000  -37.8 -36.0   200   48   25   9.0   4.9   21.9  71.5    12.6      M    M
 24000  -35.1 -31.2   200   44   22   9.0   4.9   21.7  71.1    12.6      M    M
 23000  -32.4 -26.3   195   40   21   9.3   5.1   21.5  70.7    12.5      M    M
 22000  -29.6 -21.3   185   38   19   9.3   5.1   21.3  70.3    12.5      M    M
 21000  -26.8 -16.2   180   36   18   9.0   4.9   21.2  70.2    12.6      M    M
 20000  -24.4 -11.9   170   34   18   8.2   4.5   20.6  69.1    12.2      M    M
 19500  -23.2  -9.8   165   33   17   8.2   4.5   20.4  68.6    12.0      M    M
 19000  -22.0  -7.6   165   33   17   8.2   4.5   20.1  68.2    11.8      M    M
 18500  -20.8  -5.4   160   33   17   8.2   4.5   19.9  67.8    11.7      M    M
 18000  -19.6  -3.3   155   32   17   7.7   4.2   19.6  67.2    11.4      M    M
 17500  -18.5  -1.3   150   32   17   7.8   4.3   19.2  66.6    11.2      M    M
 17000  -17.4   0.7   145   33   17   6.3   3.4   18.8  65.8    10.9      M    M
 16500  -16.5   2.3   140   33   17   6.0   3.3   18.1  64.6    10.3      M    M
 16000  -15.6   3.9   140   33   17   5.5   3.0   17.5  63.5     9.8      M    M
 15500  -14.6   5.7   135   31   16   4.7   2.6   16.3  61.3     8.8      M    M
 15000  -13.8   7.2   130   30   15   6.0   3.3   15.5  59.9     8.1      M    M
 14500  -12.8   9.0   130   28   14   6.5   3.6   14.9  58.9     7.7      M    M
 14000  -11.8  10.8   125   26   13   7.6   4.2   14.4  58.0     7.3      M    M
 13500  -10.5  13.1   120   23   12   8.5   4.6   14.2  57.6     7.2      M    M
 13000   -9.2  15.4   115   19   10   8.0   4.4   14.0  57.3     7.1      M    M
 12500   -8.1  17.4   110   16    8   7.0   3.8   13.6  56.5     6.7      M    M
 12000   -7.1  19.2   105   12    6   6.7   3.7   13.2  55.7     6.4      M    M
 11500   -6.2  20.8   095    9    5   6.2   3.4   12.6  54.7     5.9      M    M
 11000   -5.3  22.5   080    6    3   5.1   2.8   12.1  53.7     5.3      M    M
 10500   -4.8  23.4   050    5    3   3.3   1.8   11.1  51.9     4.4      M    M
 10250   -4.6  23.7   035    6    3   3.1   1.7   10.6  51.0     3.9      M    M
 10000   -4.4  24.1   020    6    3   4.0   2.2   10.1  50.1     3.3      M    M
  9750   -4.0  24.8   015    7    4   5.7   3.1    9.7  49.4     3.0      M    M
  9500   -3.6  25.5   005    8    4   6.2   3.4    9.4  48.9     2.7      M    M
  9250   -3.2  26.2   355    9    5   5.9   3.2    9.1  48.4     2.4      M    M
  9000   -2.8  27.0   350   11    6   3.8   2.1    8.7  47.7     2.0      M    M
  8750   -2.6  27.3   350   13    7   2.5   1.4    8.2  46.7     1.5      M    M
  8500   -2.5  27.5   350   15    8   2.6   1.4    7.6  45.7     0.9      M    M
  8250   -2.3  27.9   355   18    9   3.0   1.6    7.1  44.8     0.3      M    M
  8000   -2.1  28.2   355   20   10   3.2   1.8    6.6  43.9    -0.1    203  1.0
  7750   -1.8  28.8   355   22   12   5.1   2.8    6.1  43.0    -0.6    188  1.0
  7500   -1.3  29.7   355   23   12   6.7   3.7    5.9  42.6    -0.8    166  0.8
  7250   -0.8  30.6   350   24   12   6.5   3.5    5.6  42.1    -1.1    143  0.7
  7000   -0.3  31.5   350   22   11   6.9   3.8    5.4  41.7    -1.3    121  0.6
  6750    0.2  32.4   345   20   10   6.2   3.4    5.2  41.3    -1.5     98  0.5
  6500    0.6  33.1   340   18    9   5.3   2.9    4.8  40.7    -1.8     78  0.4
  6250    1.0  33.8   335   15    8   5.2   2.9    4.5  40.1    -2.2     59  0.3
  6000    1.4  34.5   325   12    6   5.2   2.9    4.2  39.5    -2.6     41  0.2
  5750    1.7  35.1   310    9    5   5.3   2.9    3.8  38.9    -2.9     23  0.1
  5500    2.1  35.8   290    7    4   4.4   2.4    3.5  38.2    -3.3      5  0.0

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

           04/16/2015 at 0900 MDT          |       04/16/2015 at 1200 MDT
                                           |
K index... +15.7  LI... +275.9             | K index... +17.8  LI... +275.0
CAPE... 0.0  CIN... -0.4                   | 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 -56.6 -69.9  240  14  7   2.6   1.4 | -56.5 -69.7  230  14  7   3.0   1.6
 45000 -52.7 -62.9  245  19 10   2.4   1.3 | -51.9 -61.4  225  18  9   1.4   0.7
 40000 -49.5 -57.1  220  22 11   2.0   1.1 | -49.9 -57.8  210  24 12   1.3   0.7
 38000 -48.8 -55.8  220  26 13  -0.0  -0.0 | -49.4 -56.9  205  27 14   0.5   0.3
 36000 -48.8 -55.8  220  33 17  -0.0  -0.0 | -49.0 -56.2  200  31 16   0.5   0.3
 34000 -48.8 -55.8  220  40 21   1.3   0.7 | -48.7 -55.7  200  36 19   1.8   1.0
 32000 -47.5 -53.5  210  49 25   2.1   1.2 | -47.0 -52.6  200  51 26   2.5   1.3
 30000 -45.8 -50.4  200  58 30   5.8   3.2 | -45.3 -49.5  195  62 32   5.9   3.2
 29000 -44.2 -47.6  200  57 29   5.5   3.0 | -43.6 -46.5  195  61 32   5.6   3.1
 28000 -42.6 -44.7  195  56 29   5.5   3.0 | -41.9 -43.4  190  61 31   5.6   3.1
 27000 -40.9 -41.6  190  54 28   5.6   3.1 | -40.3 -40.5  190  60 31   5.8   3.2
 26000 -38.7 -37.7  190  52 27   8.0   4.4 | -38.1 -36.6  190  57 30   7.5   4.1
 25000 -36.3 -33.3  190  49 25   8.0   4.4 | -35.9 -32.6  190  54 28   7.5   4.1
 24000 -33.9 -29.0  190  47 24   8.1   4.4 | -33.6 -28.5  185  50 26   7.5   4.1
 23000 -31.7 -25.1  185  42 22   7.3   4.0 | -31.4 -24.5  190  47 24   7.7   4.2
 22000 -29.5 -21.1  185  37 19   7.3   4.0 | -29.1 -20.4  190  44 22   7.7   4.2
 21000 -27.3 -17.1  180  32 16   7.7   4.2 | -26.8 -16.2  190  40 21   7.8   4.3
 20000 -24.9 -12.8  175  29 15   8.4   4.6 | -24.4 -11.9  180  35 18   8.0   4.4
 19500 -23.6 -10.5  170  28 15   8.5   4.6 | -23.2  -9.8  175  33 17   8.0   4.4
 19000 -22.4  -8.3  165  28 14   8.5   4.6 | -22.1  -7.8  170  31 16   8.1   4.4
 18500 -21.1  -6.0  160  27 14   8.4   4.6 | -20.9  -5.6  165  30 15   8.1   4.5
 18000 -19.9  -3.8  160  28 14   7.9   4.3 | -19.6  -3.3  160  30 15   8.4   4.6
 17500 -18.8  -1.8  165  28 14   7.9   4.4 | -18.4  -1.1  155  30 16   8.4   4.6
 17000 -17.6   0.3  160  29 15   7.6   4.2 | -17.2   1.0  155  31 16   7.5   4.1
 16500 -16.5   2.3  155  30 16   7.6   4.2 | -15.6   3.9  150  32 16   7.5   4.1
 16000 -15.4   4.3  155  32 16   7.5   4.1 | -14.5   5.9  145  32 17   7.7   4.2
 15500 -13.7   7.3  145  33 17   7.4   4.1 | -13.3   8.1  145  33 17   7.7   4.2
 15000 -12.6   9.3  140  34 17   8.1   4.4 | -12.2  10.0  145  33 17   7.8   4.3
 14500 -11.4  11.5  135  34 17   8.2   4.5 | -11.1  12.0  145  33 17   7.9   4.3
 14000 -10.2  13.6  130  34 17   8.7   4.8 | -10.0  14.0  140  33 17   7.7   4.2
 13500  -8.8  16.2  130  32 16   8.8   4.8 |  -8.9  16.0  135  32 16   7.5   4.1
 13000  -7.5  18.5  125  31 16   7.5   4.1 |  -7.8  18.0  130  32 16   6.2   3.4
 12500  -6.6  20.1  115  28 15   5.8   3.2 |  -7.1  19.2  120  31 16   4.8   2.6
 12000  -5.7  21.7  110  26 14   4.6   2.5 |  -6.4  20.5  110  31 16   3.3   1.8
 11500  -5.3  22.5  100  23 12   2.9   1.6 |  -6.1  21.0  095  27 14   1.7   0.9
 11000  -4.9  23.2  090  21 11   3.7   2.0 |  -5.8  21.6  085  25 13   2.7   1.5
 10500  -4.1  24.6  075  17  9   4.8   2.7 |  -5.2  22.6  070  22 12   4.1   2.2
 10250  -3.8  25.2  065  16  8   4.8   2.7 |  -4.9  23.2  060  22 11   2.5   1.4
 10000  -3.4  25.9  060  15  8   3.0   1.6 |  -4.8  23.4  055  21 11   2.5   1.4
  9750  -3.3  26.1  050  14  7   2.7   1.5 |  -4.5  23.9  050  20 11   5.7   3.1
  9500  -3.0  26.6  040  13  7   3.8   2.1 |  -4.1  24.6  045  20 10   6.3   3.5
  9250  -2.8  27.0  025  13  7   3.3   1.8 |  -3.6  25.5  040  20 10   5.8   3.2
  9000  -2.6  27.3  015  14  7   2.7   1.5 |  -3.2  26.2  035  19 10   6.1   3.3
  8750  -2.4  27.7  010  14  7   3.0   1.6 |  -2.7  27.1  035  18  9   8.3   4.6
  8500  -2.2  28.0  005  15  8   3.3   1.8 |  -2.1  28.2  030  17  9   9.2   5.0
  8250  -2.0  28.4  005  17  9   3.7   2.0 |  -1.4  29.5  030  16  8   9.6   5.3
  8000  -1.7  28.9  005  18  9   4.5   2.5 |  -0.7  30.7  030  16  8  10.5   5.7
  7750  -1.4  29.5  005  20 10   4.3   2.4 |   0.1  32.2  030  16  8  10.1   5.5
  7500  -1.1  30.0  005  20 10   4.5   2.5 |   0.9  33.6  030  16  8   9.9   5.4
  7250  -0.7  30.7  005  20 10   6.8   3.7 |   1.6  34.9  030  16  8   9.9   5.4
  7000  -0.1  31.8  010  17  9   7.9   4.3 |   2.3  36.1  030  16  8   9.7   5.3
  6750   0.5  32.9  010  15  8   8.6   4.7 |   3.1  37.6  030  16  8  10.2   5.6
  6500   1.2  34.2  010  13  7  10.2   5.6 |   3.9  39.0  030  15  8  11.0   6.0
  6250   2.0  35.6  010  12  6  10.3   5.7 |   4.7  40.5  025  15  8  11.3   6.2
  6000   2.7  36.9  010  11  5  10.0   5.5 |   5.5  41.9  025  15  8  10.5   5.8
  5750   3.5  38.3  015  10  5  11.4   6.2 |   6.4  43.5  025  14  7  13.4   7.3
  5500   4.5  40.1  015   9  5  16.6   9.1 |   7.7  45.9  025  14  7  23.0  12.6

           04/16/2015 at 1500 MDT          |       04/16/2015 at 1800 MDT
                                           |
K index... +14.7  LI... +273.4             | K index... +26.7  LI... +272.5
CAPE... +2.3  CIN... -4.7                  | CAPE... +63.7  CIN... -9.0
                                           |
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 -56.4 -69.5  225  15  8   3.6   2.0 | -57.4 -71.3  235  17  9   3.2   1.8
 45000 -51.2 -60.2  215  21 11   1.8   1.0 | -52.3 -62.1  225  21 11   2.8   1.5
 40000 -48.4 -55.1  170  20 11   1.8   1.0 | -48.1 -54.6  190  25 13   2.8   1.5
 38000 -48.3 -54.9  170  24 12  -1.8  -1.0 | -47.6 -53.7  185  28 14  -1.4  -0.7
 36000 -49.4 -56.9  185  30 15  -1.8  -1.0 | -48.4 -55.1  180  31 16  -1.4  -0.7
 34000 -50.4 -58.7  190  37 19   1.5   0.9 | -49.1 -56.4  180  34 18   1.3   0.7
 32000 -48.0 -54.4  200  55 28   3.5   1.9 | -47.6 -53.7  190  53 27   2.2   1.2
 30000 -45.6 -50.1  205  69 36   6.5   3.6 | -45.9 -50.6  190  67 35   6.7   3.7
 29000 -43.7 -46.7  200  69 36   6.3   3.5 | -43.9 -47.0  190  66 34   6.4   3.5
 28000 -41.8 -43.2  200  69 35   6.3   3.5 | -42.0 -43.6  190  64 33   6.4   3.5
 27000 -40.0 -40.0  195  69 35   6.5   3.6 | -40.1 -40.2  185  63 32   6.8   3.7
 26000 -37.7 -35.9  195  66 34   7.9   4.4 | -37.7 -35.9  185  61 31   8.2   4.5
 25000 -35.3 -31.5  195  63 32   7.9   4.4 | -35.3 -31.5  185  59 30   8.2   4.5
 24000 -32.9 -27.2  195  60 31   7.9   4.4 | -32.8 -27.0  180  57 29   8.3   4.5
 23000 -30.5 -22.9  190  55 28   8.1   4.5 | -30.2 -22.4  180  54 28   9.0   4.9
 22000 -28.1 -18.6  190  50 26   8.1   4.5 | -27.5 -17.5  180  51 26   9.0   4.9
 21000 -25.6 -14.1  190  44 23   7.6   4.2 | -24.9 -12.8  175  49 25   8.0   4.4
 20000 -23.6 -10.5  185  39 20   6.8   3.7 | -22.8  -9.0  170  42 22   6.9   3.8
 19500 -22.6  -8.7  185  36 18   6.8   3.7 | -21.8  -7.2  170  39 20   6.9   3.8
 19000 -21.6  -6.9  180  33 17   6.8   3.7 | -20.8  -5.4  165  37 19   6.9   3.8
 18500 -20.6  -5.1  175  30 16   7.0   3.8 | -19.8  -3.6  160  34 17   7.0   3.8
 18000 -19.5  -3.1  175  30 15   7.6   4.2 | -18.7  -1.7  155  32 16   7.2   3.9
 17500 -18.3  -0.9  170  30 15   7.6   4.2 | -17.7   0.1  150  30 16   7.2   3.9
 17000 -16.7   1.9  165  29 15   7.1   3.9 | -16.6   2.1  150  29 15   7.1   3.9
 16500 -15.6   3.9  160  29 15   7.1   3.9 | -15.1   4.8  145  27 14   7.1   3.9
 16000 -14.5   5.9  160  29 15   7.4   4.1 | -14.0   6.8  145  27 14   7.1   3.9
 15500 -13.4   7.9  160  28 15   7.5   4.1 | -13.0   8.6  145  26 14   7.2   3.9
 15000 -12.4   9.7  160  28 14   7.0   3.9 | -11.9  10.6  145  26 13   7.2   3.9
 14500 -11.4  11.5  155  28 14   7.0   3.9 | -10.9  12.4  140  24 12   7.2   3.9
 14000 -10.4  13.3  155  27 14   7.4   4.1 |  -9.8  14.4  140  23 12   6.9   3.8
 13500  -9.3  15.3  150  25 13   7.7   4.2 |  -8.8  16.2  130  21 11   6.8   3.7
 13000  -8.3  17.1  145  24 12   8.4   4.6 |  -7.9  17.8  125  20 10   6.6   3.6
 12500  -7.0  19.4  135  22 11   8.7   4.8 |  -6.9  19.6  110  22 11   6.5   3.6
 12000  -5.7  21.7  125  22 11   6.0   3.3 |  -6.0  21.2  100  24 12   7.5   4.1
 11500  -5.3  22.5  105  21 11   2.7   1.5 |  -4.8  23.4  095  26 13   8.5   4.7
 11000  -4.9  23.2  090  21 11   3.6   2.0 |  -3.5  25.7  090  29 15   7.7   4.2
 10500  -4.2  24.4  075  20 10   5.4   2.9 |  -2.6  27.3  080  27 14   7.1   3.9
 10250  -3.9  25.0  070  20 10   1.9   1.0 |  -2.1  28.2  075  27 14   5.0   2.7
 10000  -3.9  25.0  065  20 10   2.9   1.6 |  -1.8  28.8  070  27 14   4.6   2.5
  9750  -3.4  25.9  060  19 10   8.4   4.6 |  -1.4  29.5  065  26 13   6.3   3.5
  9500  -2.8  27.0  055  19 10   8.4   4.6 |  -1.0  30.2  060  26 13   5.9   3.3
  9250  -2.2  28.0  050  19 10   7.7   4.2 |  -0.5  31.1  060  25 13   5.7   3.1
  9000  -1.7  28.9  045  19 10   5.9   3.3 |  -0.2  31.6  055  24 13   5.0   2.7
  8750  -1.3  29.7  045  18  9   6.1   3.4 |   0.2  32.4  050  24 12   5.3   2.9
  8500  -0.8  30.6  045  17  9   6.4   3.5 |   0.6  33.1  050  23 12   5.7   3.1
  8250  -0.3  31.5  045  17  9   7.3   4.0 |   1.0  33.8  045  22 11   5.4   3.0
  8000   0.3  32.5  040  16  8   8.6   4.7 |   1.4  34.5  040  21 11   5.1   2.8
  7750   0.9  33.6  040  16  8   9.5   5.2 |   1.7  35.1  040  20 11   4.5   2.5
  7500   1.7  35.1  040  16  8  10.2   5.6 |   2.0  35.6  035  20 10   4.3   2.4
  7250   2.4  36.3  040  15  8   9.8   5.4 |   2.4  36.3  030  19 10   6.8   3.7
  7000   3.1  37.6  040  15  8   9.9   5.4 |   3.0  37.4  025  18  9   8.5   4.7
  6750   3.9  39.0  040  15  8   9.2   5.0 |   3.6  38.5  020  17  9   7.4   4.1
  6500   4.6  40.3  040  15  7   9.9   5.4 |   4.2  39.6  015  16  8   8.5   4.7
  6250   5.4  41.7  040  14  7  11.2   6.1 |   4.9  40.8  015  15  8  10.1   5.6
  6000   6.2  43.2  040  13  7  10.8   5.9 |   5.6  42.1  010  14  7  10.1   5.6
  5750   7.0  44.6  040  13  7  11.3   6.2 |   6.4  43.5  010  13  7   9.6   5.3
  5500   7.9  46.2  040  12  6  14.2   7.8 |   7.1  44.8  005  12  6   9.8   5.4
________________________________________________________________________________

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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