Soaring Guidance
Issued by NWS Denver/Boulder, CO

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152
UXUS97 KBOU 241306
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0706 MDT Tuesday, May 24, 2016

This forecast is for Tuesday, May 24, 2016:

If the trigger temperature of 65.9 F/18.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 823 ft/min (4.2 m/s)
   Maximum height of thermals.................. 14922 ft MSL (9637 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9653 ft MSL (4368 ft AGL)
Thermal soaring outlook for Wednesday 05/25.... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... 16846 ft MSL (11561 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 40950 ft MSL (35665 ft AGL)
Wave soaring outlook for Wednesday 05/25....... Fair

Remarks...

Sunrise/Sunset.................... 05:37:34 / 20:15:02 MDT
Total possible sunshine........... 14 hr 37 min 29 sec (877 min 29 sec)
Altitude of sun at 12:56:29 MDT... 71.16 degrees

Upper air data from rawinsonde observation taken on 05/24/2016 at 0600 MDT

Freezing level.................. 12852 ft MSL (7567 ft AGL)
Convective condensation level... 13564 ft MSL (8279 ft AGL)
Lifted condensation level....... 13819 ft MSL (8533 ft AGL)
Lifted index.................... -2.4
K index......................... +14.7

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  -60.9 -77.6   240   45   23  -0.5  -0.3   96.2 205.2    41.9      M    M
 45000  -58.3 -72.9   240   48   25   3.9   2.1   74.9 166.8    31.9      M    M
 40000  -58.3 -72.9   230   61   31   5.7   3.1   51.9 125.5    18.9      M    M
 38000  -55.8 -68.4   230   60   31   5.9   3.2   46.9 116.4    16.0      M    M
 36000  -53.1 -63.6   235   59   30   7.6   4.2   42.4 108.3    13.3      M    M
 34000  -48.8 -55.8   235   59   31   7.4   4.1   40.0 104.1    12.0      M    M
 32000  -44.4 -47.9   235   60   31   7.4   4.1   38.0 100.5    10.8      M    M
 30000  -39.2 -38.6   235   60   31   7.8   4.3   36.4  97.4     9.8      M    M
 29000  -36.9 -34.4   235   58   30   7.7   4.2   35.6  96.0     9.3      M    M
 28000  -34.4 -29.9   230   56   29   8.8   4.8   35.0  95.1     9.1      M    M
 27000  -31.7 -25.1   230   54   28   9.1   5.0   34.7  94.5     8.9      M    M
 26000  -29.7 -21.5   225   52   27   6.0   3.3   33.7  92.6     8.2      M    M
 25000  -27.9 -18.2   230   51   26   6.8   3.7   32.3  90.1     7.1      M    M
 24000  -25.2 -13.4   230   49   25   8.9   4.9   31.9  89.5     6.9      M    M
 23000  -23.0  -9.4   235   48   25   8.6   4.7   31.1  87.9     6.3      M    M
 22000  -20.5  -4.9   235   47   24   8.4   4.6   30.6  87.1     6.0      M    M
 21000  -18.2  -0.8   235   46   24   6.3   3.5   29.9  85.8     5.4      M    M
 20000  -16.4   2.5   240   45   23   8.6   4.7   28.6  83.5     4.3      M    M
 19500  -15.1   4.8   240   43   22   9.2   5.1   28.4  83.2     4.2      M    M
 19000  -14.2   6.4   235   41   21   4.7   2.6   27.9  82.3     3.7      M    M
 18500  -13.3   8.1   235   39   20   7.1   3.9   27.3  81.1     3.2      M    M
 18000  -12.2  10.0   235   38   20   7.2   4.0   26.8  80.3     2.8      M    M
 17500  -11.0  12.2   240   37   19   8.1   4.5   26.5  79.7     2.6      M    M
 17000   -9.7  14.5   240   36   18   5.2   2.8   26.3  79.3     2.4      M    M
 16500   -9.8  14.4   240   34   18  -0.5  -0.3   24.5  76.2     0.9      M    M
 16000   -8.9  16.0   245   33   17   9.7   5.3   23.9  75.1     0.3      M    M
 15500   -7.6  18.3   245   32   16   9.1   5.0   23.8  74.8     0.2      M    M
 15000   -5.6  21.9   245   30   15   9.1   5.0   23.6  74.5    -0.0    818  4.2
 14500   -4.2  24.4   245   28   14   9.1   5.0   23.5  74.3    -0.1    763  3.9
 14000   -2.9  26.8   245   27   14   9.1   5.0   23.4  74.2    -0.2    708  3.6
 13500   -1.5  29.3   250   25   13   9.1   5.0   23.3  73.9    -0.3    653  3.3
 13000   -0.2  31.6   250   23   12   9.0   5.0   23.2  73.7    -0.4    597  3.0
 12500    1.2  34.2   245   20   11   8.8   4.8   23.0  73.5    -0.6    542  2.8
 12000    2.4  36.3   245   18    9   8.5   4.7   22.8  73.1    -0.8    490  2.5
 11500    3.7  38.7   240   16    8   8.5   4.7   22.6  72.7    -1.0    437  2.2
 11000    5.0  41.0   240   15    8   8.4   4.6   22.5  72.4    -1.2    385  2.0
 10500    6.2  43.2   225   14    7   6.6   3.6   22.2  72.0    -1.4    333  1.7
 10250    6.5  43.7   215   14    7   4.3   2.4   21.8  71.3    -1.9    318  1.6
 10000    6.8  44.2   210   14    7   8.8   4.8   21.6  70.8    -2.3    300  1.5
  9750    7.2  45.0   205   15    8   1.3   0.7   21.4  70.5    -2.7    282  1.4
  9500    6.7  44.1   200   16    8  -3.0  -1.7   20.3  68.5    -4.0    290  1.5
  9250    6.9  44.4   200   16    8   4.8   2.6   19.7  67.4    -4.4    275  1.4
  9000    7.4  45.3   195   17    9   6.1   3.4   19.4  66.8    -4.7    253  1.3
  8750    7.9  46.2   195   13    7   6.6   3.6   19.1  66.4    -4.9    230  1.2
  8500    8.4  47.1   195   10    5   5.1   2.8   18.8  65.9    -5.2    207  1.1
  8250    8.6  47.5   195    7    4   3.8   2.1   18.4  65.1    -5.7    193  1.0
  8000    8.9  48.0   195    4    2   4.4   2.4   17.9  64.3    -6.2    178  0.9
  7750    9.2  48.6   200    4    2   4.3   2.4   17.5  63.6    -6.6    160  0.8
  7500    9.6  49.3   200    3    2   4.9   2.7   17.1  62.8    -7.0    142  0.7
  7250    9.9  49.8   205    3    2   5.3   2.9   16.8  62.2    -7.4    125  0.6
  7000   10.2  50.4   210    3    2   5.6   3.1   16.4  61.6    -7.8    108  0.5
  6750   10.6  51.1   215    2    1   4.4   2.4   16.1  61.0    -8.2     91  0.5
  6500   10.6  51.1   230    2    1  -2.8  -1.6   15.5  59.9    -9.0     83  0.4
  6250   10.2  50.4   255    1    1  -5.3  -2.9   14.3  57.8   -10.1     88  0.4
  6000   10.1  50.2   305    1    0   3.1   1.7   13.5  56.3   -10.9     83  0.4
  5750   10.4  50.7   310    1    0  -0.0  -0.0   13.0  55.4   -11.4     66  0.3
  5500    9.6  49.3   000    0    0 -22.3 -12.2   11.5  52.7   -12.9     82  0.4

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

           05/24/2016 at 0900 MDT          |       05/24/2016 at 1200 MDT
                                           |
K index... +13.9  LI... -3.6               | K index... +8.0  LI... -4.3
CAPE... +657.8  CIN... -18.5               | CAPE... +1039.8  CIN... -15.0
                                           |
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 -58.4 -73.1  255  28 14  -0.2  -0.1 | -57.5 -71.5  250  17  9   0.5   0.3
 45000 -58.7 -73.7  245  46 24   0.7   0.4 | -56.9 -70.4  245  29 15  -0.2  -0.1
 40000 -57.6 -71.7  240  58 30   0.8   0.5 | -57.2 -71.0  240  59 30  -0.1  -0.1
 38000 -55.4 -67.7  235  59 30   4.9   2.7 | -55.3 -67.5  235  61 31   4.5   2.5
 36000 -52.4 -62.3  235  58 30   4.9   2.7 | -52.6 -62.7  230  60 31   4.5   2.5
 34000 -49.0 -56.2  230  57 29   7.2   4.0 | -48.8 -55.8  230  58 30   7.2   4.0
 32000 -44.7 -48.5  230  57 29   7.2   4.0 | -44.5 -48.1  225  54 28   7.2   4.0
 30000 -39.5 -39.1  230  55 29   8.5   4.7 | -39.8 -39.6  225  52 27   8.4   4.6
 29000 -36.9 -34.4  230  54 28   8.5   4.7 | -37.3 -35.1  225  50 26   8.4   4.6
 28000 -34.4 -29.9  230  54 28   8.5   4.7 | -34.8 -30.6  220  49 25   8.4   4.6
 27000 -32.0 -25.6  230  52 27   6.9   3.8 | -32.4 -26.3  220  47 24   7.1   3.9
 26000 -29.9 -21.8  230  48 25   6.9   3.8 | -30.3 -22.5  220  45 23   7.2   3.9
 25000 -27.9 -18.2  230  44 23   6.9   3.8 | -28.1 -18.6  220  43 22   7.2   3.9
 24000 -25.8 -14.4  230  41 21   7.1   3.9 | -26.0 -14.8  220  40 21   7.4   4.1
 23000 -23.7 -10.7  230  39 20   7.1   3.9 | -23.8 -10.8  220  38 20   7.4   4.1
 22000 -21.6  -6.9  230  38 19   7.1   3.9 | -21.6  -6.9  220  36 19   7.5   4.1
 21000 -19.4  -2.9  230  36 19   7.9   4.3 | -19.3  -2.7  215  35 18   8.5   4.6
 20000 -17.0   1.4  230  35 18   7.9   4.3 | -16.8   1.8  215  35 18   8.4   4.6
 19500 -15.9   3.4  230  35 18   7.9   4.3 | -15.5   4.1  215  34 18   8.4   4.6
 19000 -14.7   5.5  230  34 18   7.8   4.3 | -14.2   6.4  215  34 18   8.4   4.6
 18500 -13.5   7.7  230  34 17   8.2   4.5 | -13.0   8.6  215  34 17   8.4   4.6
 18000 -12.3   9.9  230  33 17   8.2   4.5 | -11.8  10.8  220  33 17   8.4   4.6
 17500 -11.1  12.0  230  33 17   8.3   4.5 |  -9.9  14.2  220  32 17   8.3   4.5
 17000  -9.8  14.4  230  32 16   8.4   4.6 |  -8.6  16.5  220  32 16   8.3   4.5
 16500  -8.6  16.5  235  31 16   8.5   4.7 |  -7.4  18.7  225  31 16   8.2   4.5
 16000  -6.8  19.8  235  29 15   7.9   4.3 |  -6.2  20.8  225  30 15   8.1   4.4
 15500  -5.6  21.9  235  28 15   7.7   4.3 |  -5.0  23.0  225  29 15   8.0   4.4
 15000  -4.6  23.7  235  27 14   6.7   3.7 |  -3.9  25.0  225  27 14   7.4   4.0
 14500  -3.6  25.5  240  25 13   6.6   3.6 |  -2.8  27.0  225  26 13   7.5   4.1
 14000  -2.5  27.5  240  23 12   7.9   4.3 |  -1.7  28.9  225  24 12   6.6   3.6
 13500  -1.4  29.5  240  21 11   7.7   4.2 |  -0.7  30.7  225  22 11   6.7   3.6
 13000  -0.2  31.6  235  19 10   9.3   5.1 |   0.3  32.5  220  20 10   7.2   4.0
 12500   1.2  34.2  235  18  9   9.5   5.2 |   1.3  34.3  220  18  9   7.3   4.0
 12000   2.6  36.7  230  17  9   7.7   4.2 |   2.4  36.3  215  17  9   8.9   4.9
 11500   3.6  38.5  230  15  8   7.3   4.0 |   3.8  38.8  215  16  8   9.4   5.1
 11000   4.5  40.1  225  13  7   3.8   2.1 |   5.2  41.4  210  15  8   7.7   4.2
 10500   4.7  40.5  220  11  6   2.7   1.5 |   6.2  43.2  205  14  7   6.9   3.8
 10250   4.8  40.6  220  10  5   2.7   1.5 |   6.7  44.1  205  13  7   8.0   4.4
 10000   5.0  41.0  210   9  5   4.4   2.4 |   7.2  45.0  200  12  6   5.5   3.0
  9750   5.3  41.5  200   8  4   5.4   3.0 |   7.4  45.3  195  10  5   2.7   1.5
  9500   5.6  42.1  190   8  4   5.4   2.9 |   7.5  45.5  185  10  5   3.6   2.0
  9250   6.0  42.8  180   7  4   4.9   2.7 |   7.7  45.9  175   9  5   4.1   2.3
  9000   6.3  43.3  175   8  4   5.8   3.2 |   7.9  46.2  170   9  4   6.4   3.5
  8750   6.7  44.1  170   8  4   7.2   3.9 |   8.3  46.9  165   8  4   7.7   4.2
  8500   7.1  44.8  165   8  4   6.9   3.8 |   8.8  47.8  155   8  4   7.1   3.9
  8250   7.6  45.7  165   9  4   7.3   4.0 |   9.2  48.6  150   8  4   9.2   5.0
  8000   8.1  46.6  160  10  5   7.6   4.1 |  10.0  50.0  145   8  4  10.9   6.0
  7750   8.6  47.5  160  10  5   7.4   4.0 |  10.7  51.3  145   8  4   9.6   5.3
  7500   9.1  48.4  155  11  6   7.3   4.0 |  11.4  52.5  145   8  4   9.4   5.1
  7250   9.5  49.1  155  12  6   6.0   3.3 |  12.1  53.8  145   8  4  10.2   5.6
  7000   9.9  49.8  150  12  6   5.2   2.8 |  12.9  55.2  145   7  4  10.8   5.9
  6750  10.3  50.5  150  13  7   3.2   1.7 |  13.7  56.7  140   7  4   9.3   5.1
  6500  10.6  51.1  150  13  6   3.5   1.9 |  14.4  57.9  140   7  4   9.5   5.2
  6250  11.0  51.8  150  11  5   6.8   3.7 |  15.1  59.2  140   7  4  11.2   6.2
  6000  11.6  52.9  150   8  4   6.6   3.6 |  16.0  60.8  140   7  3  11.8   6.4
  5750  12.2  54.0  150   5  3   8.4   4.6 |  16.8  62.2  140   6  3  10.5   5.8
  5500  13.1  55.6  145   4  2  16.8   9.2 |  17.7  63.9  140   6  3  16.8   9.2

           05/24/2016 at 1500 MDT          |       05/24/2016 at 1800 MDT
                                           |
K index... +28.6  LI... -5.7               | K index... +29.4  LI... -5.7
CAPE... +1564.4  CIN... -0.7               | CAPE... +1204.2  CIN... -25.0
                                           |
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 -57.4 -71.3  245  18  9   1.0   0.5 | -57.7 -71.9  235  16  8   1.3   0.7
 45000 -56.1 -69.0  245  26 14  -0.1  -0.1 | -55.9 -68.6  235  20 10   0.4   0.2
 40000 -56.4 -69.5  240  61 31  -0.1  -0.1 | -55.3 -67.5  240  58 30   0.3   0.2
 38000 -54.8 -66.6  235  64 33   3.8   2.1 | -53.8 -64.8  235  59 30   3.2   1.8
 36000 -52.2 -62.0  230  61 32   3.9   2.1 | -51.9 -61.4  235  57 29   3.2   1.8
 34000 -49.0 -56.2  230  59 30   7.1   3.9 | -49.0 -56.2  235  54 28   7.5   4.1
 32000 -44.7 -48.5  230  55 28   7.1   3.9 | -44.5 -48.1  235  51 26   7.4   4.1
 30000 -40.1 -40.2  225  52 27   8.3   4.6 | -40.0 -40.0  235  48 25   7.9   4.4
 29000 -37.6 -35.7  225  50 26   8.3   4.6 | -37.6 -35.7  235  47 24   7.9   4.3
 28000 -35.1 -31.2  225  48 25   8.3   4.6 | -34.6 -30.3  235  46 24   7.9   4.4
 27000 -32.6 -26.7  225  47 24   7.8   4.3 | -32.3 -26.1  235  45 23   7.9   4.4
 26000 -30.3 -22.5  225  46 24   7.8   4.3 | -29.9 -21.8  235  45 23   7.9   4.4
 25000 -27.9 -18.2  225  44 23   7.8   4.3 | -27.5 -17.5  240  45 23   7.9   4.4
 24000 -25.6 -14.1  225  43 22   7.4   4.0 | -25.2 -13.4  240  44 23   7.8   4.3
 23000 -23.4 -10.1  225  42 21   7.3   4.0 | -22.9  -9.2  235  43 22   7.9   4.3
 22000 -21.2  -6.2  225  40 21   7.3   4.0 | -20.5  -4.9  235  42 22   7.8   4.3
 21000 -19.0  -2.2  225  39 20   7.9   4.3 | -18.4  -1.1  235  41 21   6.2   3.4
 20000 -16.6   2.1  225  39 20   7.9   4.3 | -16.5   2.3  225  38 19   6.3   3.5
 19500 -15.5   4.1  225  38 20   7.9   4.3 | -15.6   3.9  220  37 19   6.3   3.5
 19000 -14.3   6.3  225  38 20   7.8   4.3 | -14.7   5.5  215  36 18   6.1   3.4
 18500 -13.1   8.4  225  38 19   8.3   4.5 | -13.7   7.3  210  35 18   8.4   4.6
 18000 -11.3  11.7  225  36 19   8.4   4.6 | -12.5   9.5  205  34 18   8.3   4.6
 17500 -10.0  14.0  225  35 18   8.2   4.5 | -11.3  11.7  205  34 17   8.7   4.8
 17000  -8.8  16.2  225  34 17   8.2   4.5 |  -9.9  14.2  200  33 17   9.2   5.1
 16500  -7.6  18.3  225  32 17   8.2   4.5 |  -8.6  16.5  200  32 16   9.3   5.1
 16000  -6.5  20.3  220  30 16   8.1   4.4 |  -7.2  19.0  200  31 16   9.3   5.1
 15500  -5.3  22.5  220  29 15   8.1   4.5 |  -5.8  21.6  195  30 15   9.3   5.1
 15000  -4.2  24.4  215  27 14   8.1   4.5 |  -3.8  25.2  195  28 14   9.4   5.2
 14500  -3.0  26.6  210  25 13   8.3   4.5 |  -2.4  27.7  195  27 14   9.5   5.2
 14000  -1.9  28.6  205  23 12   7.7   4.2 |  -1.0  30.2  195  25 13   9.3   5.1
 13500  -0.9  30.4  195  21 11   7.9   4.3 |   0.3  32.5  190  24 12   9.3   5.1
 13000   0.2  32.4  185  19 10   8.2   4.5 |   1.7  35.1  190  22 11   9.0   5.0
 12500   1.3  34.3  175  17  9   8.3   4.5 |   2.9  37.2  190  19 10   9.1   5.0
 12000   2.5  36.5  165  15  8   8.8   4.8 |   4.2  39.6  185  17  9   8.4   4.6
 11500   3.7  38.7  155  14  7   9.0   4.9 |   5.4  41.7  185  14  7   8.1   4.5
 11000   5.0  41.0  150  13  7   8.7   4.8 |   6.5  43.7  185  11  6   7.4   4.0
 10500   6.3  43.3  145  13  6   7.9   4.3 |   7.5  45.5  185   8  4   6.7   3.6
 10250   6.9  44.4  145  12  6  11.4   6.3 |   8.0  46.4  185   7  3   9.0   4.9
 10000   7.9  46.2  145  12  6  12.3   6.7 |   8.7  47.7  185   5  2   9.5   5.2
  9750   8.6  47.5  140  12  6   9.3   5.1 |   9.3  48.7  195   3  1   7.6   4.2
  9500   9.4  48.9  140  12  6  10.3   5.7 |   9.8  49.6  220   1  1   8.1   4.4
  9250  10.1  50.2  140  12  6   9.2   5.0 |  10.4  50.7  320   1  1   8.1   4.4
  9000  10.8  51.4  140  11  6   9.4   5.2 |  11.0  51.8  340   3  2   7.8   4.3
  8750  11.5  52.7  140  11  6  10.5   5.8 |  11.5  52.7  345   5  3   7.3   4.0
  8500  12.3  54.1  140  11  6  10.2   5.6 |  12.0  53.6  345   7  3   7.3   4.0
  8250  13.1  55.6  140  11  6  10.4   5.7 |  12.6  54.7  345   8  4   7.9   4.3
  8000  13.8  56.8  140  11  5  10.0   5.5 |  13.1  55.6  345  11  5   8.5   4.6
  7750  14.6  58.3  140  10  5   9.4   5.2 |  13.7  56.7  345  12  6   8.1   4.4
  7500  15.3  59.5  135  10  5   9.1   5.0 |  14.3  57.7  345  13  7   7.8   4.3
  7250  16.0  60.8  135  10  5  10.5   5.7 |  14.9  58.8  345  15  8   8.7   4.8
  7000  16.8  62.2  135  10  5  11.5   6.3 |  15.6  60.1  345  16  8   9.6   5.3
  6750  17.6  63.7  135  10  5   9.9   5.4 |  16.3  61.3  345  17  9   9.0   4.9
  6500  18.3  64.9  135   9  5   9.6   5.3 |  16.9  62.4  340  17  9   8.9   4.9
  6250  19.1  66.4  135   9  5  10.7   5.9 |  17.6  63.7  340  18  9  10.5   5.8
  6000  19.9  67.8  135   9  5  11.8   6.5 |  18.5  65.3  340  17  9  11.8   6.5
  5750  20.7  69.3  135   9  4   9.8   5.4 |  19.3  66.7  340  17  9   9.9   5.4
  5500  21.5  70.7  130   8  4  14.3   7.9 |  20.0  68.0  340  17  9  11.4   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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