Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 191354
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0754 MDT Tuesday, May 19, 2015

This forecast is for Tuesday, May 19, 2015:

If the trigger temperature of 54.0 F/12.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5285 ft MSL (0 ft AGL)

Forecast maximum temperature................... 47.0 F/8.8 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................. None
Thermal soaring outlook for Wednesday 05/20.... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No chnage
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 16115 ft MSL (10830 ft AGL)
Wave soaring outlook for Wednesday 05/20....... Poor

Remarks...

Sunrise/Sunset.................... 05:41:44 / 20:10:00 MDT
Total possible sunshine........... 14 hr 28 min 16 sec (868 min 16 sec)
Altitude of sun at 12:56:04 MDT... 70.04 degrees

Upper air data from rawinsonde observation taken on 05/19/2015 at 0600 MDT

Freezing level.................. 9732 ft MSL (4447 ft AGL)
Convective condensation level... 10771 ft MSL (5486 ft AGL)
Lifted condensation level....... 7936 ft MSL (2650 ft AGL)
Lifted index.................... +10.4
K index......................... +19.7

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  -55.6 -68.1   240   28   14  -9.4  -5.1  106.5 223.6    56.2      M    M
 45000  -59.4 -74.9   230   52   27  -0.0  -0.0   74.2 165.6    40.5      M    M
 40000  -65.0 -85.0   190  100   51   2.5   1.4   42.6 108.7    22.6      M    M
 38000  -60.8 -77.4   185   87   45   9.3   5.1   40.1 104.2    21.5      M    M
 36000  -54.9 -66.8   180   75   39   9.8   5.4   40.0 104.0    22.1      M    M
 34000  -49.2 -56.6   175   66   34   9.1   5.0   40.0 104.0    22.6      M    M
 32000  -43.9 -47.0   180   61   31   8.8   4.8   39.1 102.5    22.6      M    M
 30000  -38.2 -36.8   180   51   26   8.3   4.6   38.3 100.9    22.6      M    M
 29000  -35.7 -32.3   180   46   24   8.3   4.6   37.7  99.8    22.4      M    M
 28000  -33.2 -27.8   180   41   21   8.3   4.6   37.2  98.9    22.2      M    M
 27000  -30.7 -23.3   180   41   21   8.3   4.6   36.5  97.7    22.0      M    M
 26000  -28.3 -18.9   175   40   21   8.2   4.5   35.9  96.6    21.8      M    M
 25000  -25.8 -14.4   175   40   21   8.2   4.5   35.4  95.6    21.5      M    M
 24000  -23.5 -10.3   175   39   20   7.0   3.8   34.6  94.4    21.2      M    M
 23000  -21.4  -6.5   180   35   18   6.4   3.5   33.6  92.5    20.6      M    M
 22000  -19.6  -3.3   190   31   16   6.3   3.4   32.3  90.1    19.7      M    M
 21000  -17.7   0.1   200   28   14   6.3   3.5   31.1  87.9    18.9      M    M
 20000  -15.9   3.4   215   26   13   6.3   3.5   30.0  86.0    18.1      M    M
 19500  -14.9   5.2   215   26   13   6.3   3.5   29.4  84.8    17.7      M    M
 19000  -14.0   6.8   210   26   13   6.4   3.5   28.7  83.7    17.2      M    M
 18500  -13.1   8.4   210   26   13   6.0   3.3   28.1  82.6    16.7      M    M
 18000  -12.2  10.0   215   26   14   6.1   3.3   27.5  81.5    16.3      M    M
 17500  -11.3  11.7   215   27   14   6.1   3.3   26.9  80.3    15.8      M    M
 17000  -10.4  13.3   220   27   14   6.1   3.3   26.3  79.3    15.3      M    M
 16500   -9.6  14.7   210   27   14   6.1   3.3   25.6  78.2    14.8      M    M
 16000   -8.7  16.3   200   29   15   6.1   3.3   25.0  77.0    14.3      M    M
 15500   -7.8  18.0   200   29   15   6.1   3.4   24.4  75.9    13.8      M    M
 15000   -6.5  20.3   195   28   14   6.1   3.3   23.4  74.2    13.0      M    M
 14500   -5.6  21.9   195   27   14   5.4   3.0   22.8  73.1    12.5      M    M
 14000   -4.9  23.2   195   27   14   4.3   2.4   22.0  71.5    11.8      M    M
 13500   -4.3  24.3   190   27   14   4.3   2.4   21.0  69.9    11.0      M    M
 13000   -3.7  25.3   185   27   14   4.3   2.4   20.1  68.2    10.2      M    M
 12500   -3.1  26.4   185   28   14   4.3   2.4   19.3  66.7     9.4      M    M
 12000   -2.5  27.5   180   28   14   4.3   2.4   18.4  65.2     8.7      M    M
 11500   -1.8  28.8   185   25   13   4.3   2.4   17.5  63.6     7.8      M    M
 11000   -1.2  29.8   190   22   11   4.3   2.4   16.7  62.0     7.0      M    M
 10500   -0.6  30.9   185   21   11   4.6   2.5   15.8  60.4     6.2      M    M
 10250   -0.3  31.5   180   21   11   3.0   1.6   15.3  59.6     5.8      M    M
 10000   -0.2  31.6   175   22   11   1.6   0.9   14.7  58.5     5.2      M    M
  9750    0.0  32.0   175   22   11   2.4   1.3   14.1  57.4     4.7      M    M
  9500    0.2  32.4   175   22   11   1.7   0.9   13.5  56.3     4.1      M    M
  9250    0.3  32.5   175   22   11   3.6   2.0   12.9  55.3     3.6      M    M
  9000    0.8  33.4   175   22   11   6.8   3.7   12.6  54.7     3.3      M    M
  8750    1.3  34.3   170   24   12   7.3   4.0   12.4  54.3     3.1      M    M
  8500    1.8  35.2   165   25   13   7.1   3.9   12.2  54.0     2.9      M    M
  8250    2.3  36.1   165   27   14   7.2   3.9   12.0  53.6     2.7      M    M
  8000    2.9  37.2   160   29   15   7.2   3.9   11.8  53.3     2.5      M    M
  7750    3.4  38.1   160   28   15   7.2   3.9   11.6  52.9     2.3      M    M
  7500    3.9  39.0   160   28   14   7.2   3.9   11.4  52.5     2.1      M    M
  7250    4.4  39.9   160   28   14   7.2   3.9   11.2  52.2     1.9      M    M
  7000    5.0  41.0   160   27   14   7.2   3.9   11.0  51.8     1.7      M    M
  6750    5.5  41.9   155   25   13   7.1   3.9   10.8  51.4     1.5      M    M
  6500    6.0  42.8   150   24   12   7.0   3.8   10.6  51.1     1.3      M    M
  6250    6.5  43.7   145   22   11   7.0   3.9   10.4  50.7     1.0      M    M
  6000    6.9  44.4   140   21   11   7.1   3.9   10.2  50.3     0.8      M    M
  5750    7.4  45.3   135   17    9   7.0   3.8   10.0  50.0     0.5      M    M
  5500    7.9  46.2   125   13    6   7.4   4.1    9.8  49.6     0.3      M    M

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

           05/19/2015 at 0900 MDT          |       05/19/2015 at 1200 MDT
                                           |
K index... +15.5  LI... +277.7             | K index... +21.9  LI... +274.4
CAPE... +18.9  CIN... -0.6                 | CAPE... +38.7  CIN... -1.8
                                           |
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 -57.3 -71.1  240  27 14   0.7   0.4 | -56.8 -70.2  245  24 12   1.3   0.7
 45000 -56.6 -69.9  225  35 18  -1.8  -1.0 | -54.8 -66.6  235  36 18   0.6   0.3
 40000 -59.2 -74.6  180  50 26  -1.6  -0.9 | -53.8 -64.8  210  51 26   0.6   0.3
 38000 -57.2 -71.0  175  53 27   5.6   3.1 | -52.6 -62.7  205  57 30   2.9   1.6
 36000 -53.8 -64.8  170  53 27   5.6   3.1 | -50.8 -59.4  200  64 33   2.9   1.6
 34000 -49.7 -57.5  165  54 28   9.3   5.1 | -48.5 -55.3  195  69 36   6.6   3.6
 32000 -44.1 -47.4  165  54 28   9.3   5.1 | -43.9 -47.0  195  71 36   6.8   3.7
 30000 -38.2 -36.8  165  53 27   7.9   4.4 | -39.9 -39.8  190  70 36   6.6   3.6
 29000 -35.9 -32.6  165  53 27   7.9   4.4 | -37.9 -36.2  195  68 35   6.6   3.6
 28000 -33.5 -28.3  165  53 27   8.0   4.4 | -35.9 -32.6  195  66 34   6.6   3.6
 27000 -31.3 -24.3  170  52 27   5.9   3.2 | -34.0 -29.2  195  63 33   6.3   3.4
 26000 -29.5 -21.1  170  49 25   6.0   3.3 | -32.1 -25.8  195  58 30   6.2   3.4
 25000 -27.7 -17.9  175  47 24   6.0   3.3 | -30.2 -22.4  200  52 27   6.3   3.4
 24000 -25.8 -14.4  180  44 23   7.3   4.0 | -28.4 -19.1  205  47 24   6.7   3.7
 23000 -23.6 -10.5  185  41 21   7.5   4.1 | -26.3 -15.3  205  44 23   7.1   3.9
 22000 -21.4  -6.5  190  38 20   7.5   4.1 | -24.1 -11.4  205  41 21   7.2   3.9
 21000 -19.1  -2.4  200  36 19   7.7   4.2 | -22.0  -7.6  205  37 19   7.7   4.2
 20000 -16.9   1.6  205  36 19   7.7   4.2 | -19.7  -3.5  200  33 17   7.8   4.3
 19500 -15.7   3.7  210  37 19   7.7   4.2 | -18.6  -1.5  200  31 16   7.8   4.3
 19000 -14.6   5.7  215  37 19   7.7   4.2 | -17.4   0.7  200  28 15   7.8   4.3
 18500 -13.5   7.7  215  38 20   7.4   4.1 | -16.3   2.7  200  26 14   7.9   4.4
 18000 -12.4   9.7  215  39 20   7.4   4.0 | -15.1   4.8  195  25 13   8.0   4.4
 17500 -11.3  11.7  220  40 21   7.5   4.1 | -13.9   7.0  190  25 13   8.0   4.4
 17000 -10.1  13.8  220  39 20   8.3   4.6 | -12.7   9.1  185  24 13   8.3   4.5
 16500  -8.9  16.0  220  38 19   8.4   4.6 | -10.9  12.4  185  24 12   8.1   4.4
 16000  -7.2  19.0  225  35 18   7.0   3.8 |  -9.8  14.4  185  24 12   7.3   4.0
 15500  -6.3  20.7  225  33 17   7.2   4.0 |  -8.7  16.3  190  24 12   7.5   4.1
 15000  -5.6  21.9  225  31 16   2.9   1.6 |  -7.8  18.0  195  24 12   6.3   3.4
 14500  -5.1  22.8  220  29 15   3.5   1.9 |  -6.8  19.8  200  24 12   6.4   3.5
 14000  -4.8  23.4  220  28 14   1.6   0.9 |  -5.9  21.4  210  25 13   6.3   3.4
 13500  -4.6  23.7  210  27 14   1.4   0.8 |  -5.0  23.0  215  24 12   6.3   3.4
 13000  -4.4  24.1  205  26 14   2.1   1.1 |  -4.2  24.4  215  24 12   4.0   2.2
 12500  -4.1  24.6  200  27 14   2.3   1.3 |  -3.8  25.2  220  22 12   3.0   1.6
 12000  -3.7  25.3  190  27 14   2.5   1.3 |  -3.4  25.9  225  21 11   3.0   1.6
 11500  -3.4  25.9  185  27 14   2.5   1.4 |  -3.0  26.6  225  21 11   3.1   1.7
 11000  -3.0  26.6  180  28 14   3.7   2.0 |  -2.5  27.5  225  20 10   4.5   2.5
 10500  -2.3  27.9  180  27 14   4.7   2.6 |  -1.7  28.9  215  19 10   5.5   3.0
 10250  -2.0  28.4  175  27 14   2.7   1.5 |  -1.3  29.7  210  18  9   5.2   2.9
 10000  -1.9  28.6  175  26 14   3.2   1.8 |  -1.0  30.2  210  18  9   4.0   2.2
  9750  -1.5  29.3  175  25 13   5.8   3.2 |  -0.7  30.7  205  18  9   3.6   2.0
  9500  -1.1  30.0  175  25 13   5.5   3.0 |  -0.4  31.3  200  18  9   3.8   2.1
  9250  -0.7  30.7  175  24 12   4.7   2.6 |  -0.2  31.6  190  17  9   3.6   2.0
  9000  -0.4  31.3  170  22 11   3.8   2.1 |   0.1  32.2  185  18  9   4.0   2.2
  8750  -0.1  31.8  170  21 11   5.3   2.9 |   0.4  32.7  180  17  9   5.0   2.7
  8500   0.3  32.5  170  19 10   5.6   3.1 |   0.8  33.4  175  17  9   4.9   2.7
  8250   0.7  33.3  165  17  9   6.5   3.6 |   1.1  34.0  170  18  9   6.0   3.3
  8000   1.2  34.2  165  16  8   7.6   4.2 |   1.6  34.9  165  17  9   7.4   4.1
  7750   1.7  35.1  160  14  7   7.7   4.2 |   2.1  35.8  160  16  8   6.8   3.7
  7500   2.3  36.1  155  12  6   7.8   4.3 |   2.6  36.7  155  16  8   6.8   3.7
  7250   2.8  37.0  150  11  6   7.0   3.8 |   3.1  37.6  150  15  8   7.8   4.3
  7000   3.3  37.9  140  10  5   7.1   3.9 |   3.7  38.7  140  14  7   8.5   4.7
  6750   3.8  38.8  130   9  5   5.9   3.2 |   4.3  39.7  130  14  7   7.8   4.3
  6500   4.2  39.6  115   8  4   6.8   3.7 |   4.9  40.8  120  14  7   9.2   5.0
  6250   4.8  40.6  100   8  4   8.6   4.7 |   5.6  42.1  115  13  7  11.0   6.0
  6000   5.4  41.7  085   7  4   8.0   4.4 |   6.4  43.5  110  12  6  10.4   5.7
  5750   5.9  42.6  070   8  4   8.6   4.7 |   7.2  45.0  100  11  6  11.2   6.1
  5500   6.6  43.9  065   7  4  10.2   5.6 |   8.1  46.6  095  11  5  14.3   7.9

           05/19/2015 at 1500 MDT          |       05/19/2015 at 1800 MDT
                                           |
K index... +22.3  LI... +271.8             | K index... +21.7  LI... +272.1
CAPE... +177.0  CIN... -0.4                | CAPE... +166.6  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 -56.7 -70.1  245  23 12   2.2   1.2 | -55.8 -68.4  245  26 14   2.7   1.5
 45000 -53.6 -64.5  235  35 18   1.3   0.7 | -52.1 -61.8  240  39 20   0.4   0.2
 40000 -51.7 -61.1  230  47 24   1.3   0.7 | -51.4 -60.5  240  47 24   0.5   0.2
 38000 -50.5 -58.9  225  52 27   2.4   1.3 | -50.5 -58.9  235  49 25   2.0   1.1
 36000 -49.0 -56.2  220  57 29   2.4   1.3 | -49.3 -56.7  235  51 26   2.0   1.1
 34000 -47.3 -53.1  215  60 31   5.1   2.8 | -47.8 -54.0  235  50 26   3.2   1.7
 32000 -43.8 -46.8  215  59 30   5.0   2.8 | -45.8 -50.4  235  43 22   3.2   1.8
 30000 -40.7 -41.3  215  54 28   5.7   3.2 | -43.1 -45.6  240  35 18   7.9   4.4
 29000 -39.0 -38.2  215  48 25   5.8   3.2 | -40.7 -41.3  240  30 15   8.0   4.4
 28000 -37.2 -35.0  220  42 22   5.8   3.2 | -38.3 -36.9  235  25 13   8.0   4.4
 27000 -35.5 -31.9  220  36 19   6.5   3.6 | -35.9 -32.6  235  21 11   7.7   4.2
 26000 -33.5 -28.3  220  33 17   6.8   3.7 | -33.6 -28.5  240  19 10   7.6   4.2
 25000 -31.4 -24.5  220  29 15   6.8   3.8 | -31.3 -24.3  245  18  9   7.6   4.2
 24000 -29.4 -20.9  220  26 13   7.1   3.9 | -29.0 -20.2  250  17  9   7.5   4.1
 23000 -27.2 -17.0  220  25 13   7.5   4.1 | -26.8 -16.2  250  20 10   7.4   4.1
 22000 -24.9 -12.8  220  25 13   7.6   4.1 | -24.6 -12.3  250  23 12   7.4   4.1
 21000 -22.7  -8.9  215  25 13   7.3   4.0 | -22.4  -8.3  255  25 13   7.7   4.2
 20000 -20.6  -5.1  215  26 13   7.3   4.0 | -20.1  -4.2  260  27 14   7.7   4.2
 19500 -19.5  -3.1  215  26 13   7.3   4.0 | -19.0  -2.2  260  28 14   7.7   4.2
 19000 -18.4  -1.1  220  26 14   7.3   4.0 | -17.9  -0.2  260  29 15   7.7   4.2
 18500 -17.3   0.9  220  27 14   7.5   4.1 | -16.7   1.9  265  30 15   7.4   4.1
 18000 -16.2   2.8  225  26 13   7.7   4.2 | -15.7   3.7  265  30 15   7.1   3.9
 17500 -15.1   4.8  230  26 13   7.7   4.2 | -14.1   6.6  265  30 15   7.4   4.1
 17000 -13.5   7.7  235  24 12   7.1   3.9 | -13.0   8.6  265  29 15   7.6   4.2
 16500 -12.5   9.5  240  23 12   7.1   3.9 | -11.9  10.6  265  27 14   7.5   4.1
 16000 -11.4  11.5  245  23 12   7.5   4.1 | -10.8  12.6  260  26 13   6.9   3.8
 15500 -10.3  13.5  250  22 11   7.4   4.1 |  -9.8  14.4  260  23 12   6.9   3.8
 15000  -9.2  15.4  255  23 12   7.7   4.2 |  -8.8  16.2  260  22 11   6.6   3.6
 14500  -8.0  17.6  260  24 12   7.7   4.2 |  -7.9  17.8  255  21 11   6.7   3.7
 14000  -6.9  19.6  260  24 13   7.3   4.0 |  -6.9  19.6  255  20 10   6.6   3.6
 13500  -5.9  21.4  260  24 12   7.2   3.9 |  -5.9  21.4  255  19 10   6.6   3.6
 13000  -4.8  23.4  260  24 12   6.9   3.8 |  -5.0  23.0  250  19 10   6.4   3.5
 12500  -3.8  25.2  260  23 12   6.6   3.6 |  -4.0  24.8  250  17  9   6.3   3.4
 12000  -2.9  26.8  260  22 12   5.6   3.1 |  -3.1  26.4  250  16  8   5.7   3.1
 11500  -2.2  28.0  260  21 11   4.8   2.6 |  -2.4  27.7  250  15  8   5.4   2.9
 11000  -1.5  29.3  255  20 10   3.7   2.0 |  -1.6  29.1  255  13  7   5.3   2.9
 10500  -1.2  29.8  255  17  9   3.1   1.7 |  -0.8  30.6  255  12  6   5.8   3.2
 10250  -1.0  30.2  255  16  8   1.5   0.8 |  -0.4  31.3  255  11  6   3.1   1.7
 10000  -0.9  30.4  255  15  8   4.6   2.5 |  -0.3  31.5  255  10  5   3.5   1.9
  9750  -0.3  31.5  255  14  7   8.3   4.5 |   0.1  32.2  250   9  5   6.6   3.6
  9500   0.2  32.4  250  13  7   7.6   4.2 |   0.5  32.9  245   8  4   5.9   3.2
  9250   0.7  33.3  250  12  6   6.7   3.7 |   0.9  33.6  240   7  4   5.8   3.2
  9000   1.1  34.0  240  10  5   4.8   2.6 |   1.3  34.3  230   6  3   5.8   3.2
  8750   1.5  34.7  230   9  5   5.6   3.0 |   1.8  35.2  210   6  3   6.7   3.7
  8500   1.9  35.4  215   9  4   5.9   3.3 |   2.2  36.0  190   6  3   6.7   3.7
  8250   2.3  36.1  200   8  4   6.8   3.7 |   2.7  36.9  170   6  3   7.4   4.1
  8000   2.8  37.0  180   9  4   8.1   4.4 |   3.2  37.8  155   7  4   8.3   4.6
  7750   3.4  38.1  165  10  5   7.5   4.1 |   3.8  38.8  145   8  4   8.0   4.4
  7500   3.9  39.0  150  11  5   7.2   4.0 |   4.4  39.9  135   9  5   8.0   4.4
  7250   4.4  39.9  140  12  6   8.3   4.6 |   4.9  40.8  125  10  5   8.7   4.8
  7000   5.1  41.2  130  12  6   9.2   5.0 |   5.6  42.1  115  10  5   9.2   5.0
  6750   5.7  42.3  120  13  7   8.1   4.5 |   6.2  43.2  110  11  6   8.4   4.6
  6500   6.3  43.3  110  13  7   9.1   5.0 |   6.8  44.2  100  12  6   9.1   5.0
  6250   7.0  44.6  105  12  6  11.0   6.0 |   7.6  45.7  095  12  6  10.7   5.9
  6000   7.8  46.0  095  12  6  10.8   5.9 |   8.4  47.1  090  12  6  10.4   5.7
  5750   8.6  47.5  090  11  6  11.3   6.2 |   9.1  48.4  085  12  6  10.8   5.9
  5500   9.5  49.1  085  11  5  15.4   8.4 |  10.0  50.0  085  11  6  14.0   7.7
________________________________________________________________________________

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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