Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 141231
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0531 MST Sunday, February 14, 2016

This forecast is for Sunday, February 14, 2016:

If the trigger temperature of 54.5 F/12.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 141 ft/min (0.7 m/s)
   Maximum height of thermals.................. 9876 ft MSL (4591 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 C
Time of trigger temperature.................... 1315 MST
Time of overdevelopment........................ 1700 MST
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7193 ft MSL (1907 ft AGL)
Thermal soaring outlook for Monday 02/15....... Fair

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 12184 ft MSL (6899 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 18837 ft MSL (13552 ft AGL)
Wave soaring outlook for Monday 02/15.......... Good

Remarks...

Sunrise/Sunset.................... 06:53:34 / 17:32:51 MST
Total possible sunshine........... 10 hr 39 min 17 sec (639 min 17 sec)
Altitude of sun at 12:13:31 MST... 37.26 degrees

Upper air data from rawinsonde observation taken on 02/14/2016 at 0500 MST

Freezing level.................. 9455 ft MSL (4170 ft AGL)
Convective condensation level... 18997 ft MSL (13712 ft AGL)
Lifted condensation level....... 15403 ft MSL (10118 ft AGL)
Lifted index.................... +6.2
K index......................... -5.4

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  -58.1 -72.6   305   57   29   3.4   1.9  104.0 219.1    52.0      M    M
 45000  -54.0 -65.2   290   55   28   0.6   0.3   86.2 187.2    44.8      M    M
 40000  -53.0 -63.4   290   65   33  -0.1  -0.0   64.5 148.1    33.7      M    M
 38000  -62.6 -80.7   280   61   32  -2.9  -1.6   41.1 105.9    19.0      M    M
 36000  -61.1 -78.0   280   64   33   6.1   3.4   34.6  94.2    15.0      M    M
 34000  -57.1 -70.8   280   61   31   3.4   1.8   31.8  89.2    13.5      M    M
 32000  -54.5 -66.1   300   52   27   8.7   4.8   26.3  79.3     9.9      M    M
 30000  -49.2 -56.6   305   53   27   9.5   5.2   25.7  78.2     9.6      M    M
 29000  -46.3 -51.3   310   52   27   9.5   5.2   25.5  77.9     9.7      M    M
 28000  -43.5 -46.3   310   51   26   9.5   5.2   25.5  77.8     9.7      M    M
 27000  -40.6 -41.1   305   50   26   9.5   5.2   25.2  77.4     9.7      M    M
 26000  -37.8 -36.0   305   50   26   9.5   5.2   25.1  77.2     9.7      M    M
 25000  -35.0 -31.0   300   50   26   8.2   4.5   25.0  77.0     9.7      M    M
 24000  -32.5 -26.5   295   46   24   8.8   4.8   24.5  76.0     9.4      M    M
 23000  -29.6 -21.3   295   49   25   9.6   5.3   24.3  75.8     9.4      M    M
 22000  -26.7 -16.1   290   53   27   9.6   5.3   24.2  75.6     9.5      M    M
 21000  -23.9 -11.0   290   57   29   9.6   5.3   24.3  75.7     9.6      M    M
 20000  -21.3  -6.3   290   61   31   7.4   4.0   23.9  75.0     9.4      M    M
 19500  -20.3  -4.5   290   62   32   7.3   4.0   23.4  74.2     9.0      M    M
 19000  -19.2  -2.6   285   64   33   7.3   4.0   23.0  73.4     8.7      M    M
 18500  -18.1  -0.6   290   65   33   7.5   4.1   22.6  72.7     8.4      M    M
 18000  -16.9   1.6   290   65   33   6.0   3.3   22.3  72.1     8.2      M    M
 17500  -16.4   2.5   295   64   33   4.0   2.2   21.3  70.3     7.3      M    M
 17000  -15.7   3.7   300   64   33   4.1   2.3   20.3  68.6     6.5      M    M
 16500  -14.8   5.4   300   64   33   8.5   4.6   19.7  67.4     6.0      M    M
 16000  -12.7   9.1   305   64   33   9.9   5.4   19.6  67.2     5.9      M    M
 15500  -11.4  11.5   305   63   32   8.0   4.4   19.4  66.9     5.8      M    M
 15000  -10.2  13.6   305   62   32   8.1   4.4   19.1  66.3     5.5      M    M
 14500   -8.9  16.0   305   61   31   8.1   4.5   18.8  65.8     5.3      M    M
 14000   -7.7  18.1   305   60   31   8.1   4.5   18.5  65.3     5.1      M    M
 13500   -6.5  20.3   300   59   30   8.1   4.5   18.2  64.8     4.8      M    M
 13000   -5.3  22.5   300   58   30   7.9   4.3   18.0  64.4     4.6      M    M
 12500   -4.1  24.6   300   57   29   4.5   2.5   17.8  64.1     4.5      M    M
 12000   -4.1  24.6   300   54   28   3.4   1.9   16.2  61.2     3.1      M    M
 11500   -2.8  27.0   295   39   20  -8.2  -4.5   16.1  61.0     2.9      M    M
 11000   -3.9  25.0   290   26   13  10.6   5.8   13.4  56.1     0.4      M    M
 10500   -2.6  27.3   290   23   12   8.8   4.8   13.2  55.8     0.2      M    M
 10250   -1.9  28.6   295   22   11   8.6   4.7   13.1  55.6     0.1      M    M
 10000   -1.3  29.7   295   21   11   8.5   4.6   13.0  55.5     0.0      M    M
  9750   -0.7  30.7   290   18    9   8.2   4.5   12.9  55.3    -0.1    324  1.6
  9500   -0.0  32.0   285   15    8   8.3   4.6   12.8  55.1    -0.2    298  1.5
  9250    0.6  33.1   275   12    6   8.3   4.5   12.7  54.9    -0.3    272  1.4
  9000    1.2  34.2   265   10    5   8.3   4.5   12.6  54.7    -0.4    247  1.3
  8750    1.8  35.2   270   10    5   8.3   4.6   12.5  54.5    -0.5    221  1.1
  8500    2.4  36.3   270   10    5   8.2   4.5   12.4  54.2    -0.6    195  1.0
  8250    3.0  37.4   275   11    6   8.5   4.6   12.2  54.0    -0.8    169  0.9
  8000    3.7  38.7   275   11    6   7.6   4.2   12.1  53.8    -0.9    143  0.7
  7750    4.3  39.7   270   12    6  10.8   5.9   12.0  53.6    -1.0    117  0.6
  7500    4.9  40.8   265   13    7  -1.1  -0.6   11.9  53.4    -1.1     91  0.5
  7250    4.1  39.4   265   15    8 -11.7  -6.4   10.4  50.7    -2.7    107  0.5
  7000    3.5  38.3   260   16    8  -5.3  -2.9    9.0  48.3    -4.0    118  0.6
  6750    3.1  37.6   255   14    7  -5.0  -2.8    7.9  46.2    -5.2    122  0.6
  6500    2.7  36.9   250   11    6  -5.0  -2.7    6.8  44.2    -6.3    127  0.6
  6250    2.3  36.1   245    9    5  -5.5  -3.0    5.6  42.1    -7.5    132  0.7
  6000    2.1  35.8   230    7    4   5.2   2.9    4.7  40.5    -8.4    130  0.7
  5750    2.6  36.7   210    5    3  -2.1  -1.1    4.5  40.1    -8.7    109  0.6
  5500    1.1  34.0   180    5    3 -33.4 -18.3    2.3  36.2   -10.9    146  0.7

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

           02/14/2016 at 0800 MST          |       02/14/2016 at 1100 MST
                                           |
K index... +9.9  LI... +5.4                | K index... +13.3  LI... +4.3
CAPE... 0.0  CIN... M                      | 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 -54.9 -66.8  315  32 16   0.1   0.0 | -54.1 -65.4  305  31 16   2.4   1.3
 45000 -54.8 -66.6  305  52 27   0.1   0.0 | -50.4 -58.7  295  51 26   2.2   1.2
 40000 -60.0 -76.0  290  63 32  -3.9  -2.1 | -59.5 -75.1  285  54 28  -6.9  -3.8
 38000 -61.5 -78.7  290  64 33   1.4   0.8 | -62.4 -80.3  285  55 28   2.1   1.2
 36000 -60.5 -76.9  295  55 29   1.6   0.9 | -61.2 -78.2  295  56 29   2.0   1.1
 34000 -59.5 -75.1  295  47 24   3.1   1.7 | -60.0 -76.0  305  59 30   2.6   1.4
 32000 -55.2 -67.4  305  50 26   7.5   4.1 | -55.5 -67.9  305  61 32   7.9   4.3
 30000 -50.7 -59.3  310  53 27   8.5   4.7 | -50.1 -58.2  310  63 32   9.6   5.2
 29000 -47.3 -53.1  315  51 26   9.1   5.0 | -47.3 -53.1  305  59 30   9.4   5.1
 28000 -44.5 -48.1  315  50 26   9.1   5.0 | -44.5 -48.1  305  55 28   9.4   5.1
 27000 -41.8 -43.2  315  48 25   9.2   5.0 | -41.7 -43.1  305  51 26   9.4   5.1
 26000 -38.9 -38.0  310  45 23   9.7   5.3 | -38.8 -37.8  300  46 24   9.5   5.2
 25000 -36.0 -32.8  305  42 22   9.7   5.3 | -36.0 -32.8  300  41 21   9.5   5.2
 24000 -33.1 -27.6  300  40 20   9.7   5.3 | -33.2 -27.8  295  36 18   9.6   5.3
 23000 -30.4 -22.7  300  39 20   9.0   5.0 | -30.5 -22.9  295  32 17   8.6   4.7
 22000 -27.7 -17.9  300  39 20   9.0   5.0 | -28.0 -18.4  290  30 15   8.6   4.7
 21000 -25.0 -13.0  300  40 20   8.7   4.8 | -25.4 -13.7  290  27 14   8.2   4.5
 20000 -22.6  -8.7  300  40 21   8.2   4.5 | -23.3  -9.9  295  27 14   6.8   3.8
 19500 -21.4  -6.5  300  40 21   8.2   4.5 | -22.3  -8.1  295  27 14   6.9   3.8
 19000 -20.2  -4.4  300  40 21   8.2   4.5 | -21.3  -6.3  300  28 14   6.9   3.8
 18500 -19.0  -2.2  300  40 21   8.0   4.4 | -20.3  -4.5  300  28 15   6.9   3.8
 18000 -17.9  -0.2  300  40 21   7.0   3.8 | -19.3  -2.7  305  30 15   7.0   3.8
 17500 -16.8   1.8  300  40 21   7.1   3.9 | -18.2  -0.8  305  31 16   7.0   3.9
 17000 -15.8   3.6  300  40 21   6.8   3.7 | -17.2   1.0  310  33 17   6.8   3.8
 16500 -14.8   5.4  300  40 21   6.7   3.7 | -16.2   2.8  310  34 18   6.8   3.7
 16000 -13.8   7.2  300  40 21   6.6   3.6 | -15.2   4.6  310  36 18   6.8   3.7
 15500 -12.4   9.7  305  40 20   6.5   3.5 | -13.7   7.3  310  37 19   6.8   3.7
 15000 -11.4  11.5  305  39 20   6.1   3.4 | -12.7   9.1  310  39 20   6.0   3.3
 14500 -10.6  12.9  305  40 21   6.0   3.3 | -11.9  10.6  310  40 20   5.7   3.1
 14000  -9.7  14.5  305  41 21   5.8   3.2 | -11.0  12.2  310  41 21   5.5   3.0
 13500  -8.8  16.2  305  42 21   5.6   3.1 | -10.3  13.5  310  41 21   5.3   2.9
 13000  -8.0  17.6  305  42 22   5.6   3.1 |  -9.5  14.9  310  42 21   5.2   2.9
 12500  -7.2  19.0  300  45 23   5.7   3.1 |  -8.7  16.3  310  41 21   5.2   2.9
 12000  -6.3  20.7  300  48 25   5.1   2.8 |  -8.0  17.6  310  41 21   5.3   2.9
 11500  -5.7  21.7  300  45 23   3.7   2.0 |  -7.1  19.2  305  40 21   5.6   3.1
 11000  -5.2  22.6  300  40 21   4.1   2.2 |  -6.3  20.7  305  39 20   5.6   3.0
 10500  -4.5  23.9  295  37 19   4.8   2.7 |  -5.5  22.1  305  36 19   5.3   2.9
 10250  -4.2  24.4  295  36 19   5.2   2.8 |  -5.1  22.8  305  35 18   5.9   3.2
 10000  -3.8  25.2  295  35 18   3.8   2.1 |  -4.7  23.5  305  33 17   3.8   2.1
  9750  -3.5  25.7  295  34 17   4.2   2.3 |  -4.5  23.9  305  32 16   5.3   2.9
  9500  -3.1  26.4  295  31 16   5.8   3.2 |  -3.9  25.0  305  30 15   8.6   4.7
  9250  -2.7  27.1  295  28 14   5.4   2.9 |  -3.3  26.1  305  28 14   7.6   4.2
  9000  -2.4  27.7  295  24 13   5.0   2.8 |  -2.7  27.1  305  26 13   7.3   4.0
  8750  -2.0  28.4  290  21 11   4.9   2.7 |  -2.2  28.0  305  24 12   7.1   3.9
  8500  -1.6  29.1  285  17  9   4.8   2.6 |  -1.7  28.9  305  22 11   7.3   4.0
  8250  -1.3  29.7  280  14  7   5.7   3.1 |  -1.1  30.0  305  19 10   7.4   4.1
  8000  -0.8  30.6  270  11  6   7.4   4.0 |  -0.6  30.9  305  17  9   7.9   4.3
  7750  -0.2  31.6  255   9  5   7.8   4.3 |   0.0  32.0  305  15  8   7.5   4.1
  7500   0.4  32.7  240   8  4   7.6   4.1 |   0.6  33.1  300  12  6   7.1   3.9
  7250   1.0  33.8  225   8  4   8.9   4.9 |   1.1  34.0  295  10  5   8.1   4.4
  7000   1.7  35.1  215   8  4  10.1   5.5 |   1.8  35.2  290   9  5   8.9   4.9
  6750   2.4  36.3  205   8  4   9.7   5.3 |   2.4  36.3  280   7  4   8.4   4.6
  6500   3.1  37.6  195   9  5   6.1   3.4 |   3.1  37.6  270   6  3   9.0   5.0
  6250   3.3  37.9  190  10  5   1.5   0.8 |   3.8  38.8  270   6  3  10.1   5.6
  6000   3.4  38.1  185  11  6   1.1   0.6 |   4.5  40.1  265   5  3  10.1   5.5
  5750   3.5  38.3  180  12  6   0.8   0.4 |   5.3  41.5  265   5  2  10.6   5.8
  5500   3.0  37.4  175  13  6 -19.8 -10.9 |   6.2  43.2  260   4  2  13.6   7.5

           02/14/2016 at 1400 MST          |       02/14/2016 at 1700 MST
                                           |
K index... +12.7  LI... +4.1               | K index... +14.8  LI... +2.5
CAPE... 0.0  CIN... -0.0                   | CAPE... 0.0  CIN... -0.2
                                           |
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 -55.1 -67.2  320  28 14   1.7   1.0 | -54.3 -65.7  325  27 14   0.6   0.3
 45000 -52.3 -62.1  340  35 18   1.7   0.9 | -53.3 -63.9  345  32 17   0.7   0.4
 40000 -57.9 -72.2  310  58 30  -4.3  -2.4 | -56.5 -69.7  330  66 34  -2.4  -1.3
 38000 -60.0 -76.0  300  67 34  -0.2  -0.1 | -57.6 -71.7  325  77 39   1.1   0.6
 36000 -60.2 -76.4  295  63 32  -0.3  -0.2 | -57.0 -70.6  320  67 34   0.9   0.5
 34000 -60.4 -76.7  285  60 31  -0.5  -0.3 | -56.5 -69.7  310  58 30   0.7   0.4
 32000 -55.9 -68.6  290  60 31   8.3   4.6 | -54.5 -66.1  315  57 30   3.7   2.0
 30000 -50.3 -58.5  300  61 31   9.4   5.2 | -51.9 -61.4  325  59 30   7.3   4.0
 29000 -47.5 -53.5  300  61 31   9.4   5.1 | -49.2 -56.6  320  55 29   9.1   5.0
 28000 -44.7 -48.5  300  61 31   9.4   5.1 | -46.5 -51.7  315  52 27   9.1   5.0
 27000 -41.9 -43.4  300  61 32   9.4   5.2 | -43.8 -46.8  310  50 26   9.1   5.0
 26000 -39.2 -38.6  300  59 30   8.8   4.8 | -41.0 -41.8  305  48 25   9.4   5.2
 25000 -36.5 -33.7  300  56 29   8.8   4.9 | -38.2 -36.8  305  47 24   9.4   5.2
 24000 -33.9 -29.0  300  53 27   8.9   4.9 | -35.4 -31.7  300  46 24   9.4   5.2
 23000 -31.3 -24.3  300  51 26   8.7   4.8 | -32.7 -26.9  300  45 23   8.6   4.7
 22000 -28.7 -19.7  305  48 25   8.7   4.8 | -30.2 -22.4  300  43 22   8.6   4.7
 21000 -26.1 -15.0  305  46 24   8.5   4.7 | -27.6 -17.7  305  41 21   8.6   4.7
 20000 -23.8 -10.8  310  44 22   7.4   4.1 | -25.3 -13.5  305  40 21   7.7   4.3
 19500 -22.7  -8.9  310  42 22   7.4   4.1 | -24.1 -11.4  305  39 20   7.8   4.3
 19000 -21.6  -6.9  315  41 21   7.4   4.1 | -23.0  -9.4  310  39 20   7.8   4.3
 18500 -20.5  -4.9  315  40 21   7.4   4.1 | -21.8  -7.2  310  38 20   7.8   4.3
 18000 -19.5  -3.1  315  38 20   5.5   3.0 | -20.7  -5.3  310  38 19   7.3   4.0
 17500 -18.7  -1.7  320  36 18   5.7   3.1 | -19.6  -3.3  315  37 19   7.3   4.0
 17000 -17.8  -0.0  320  34 17   6.7   3.7 | -18.5  -1.3  315  37 19   7.3   4.0
 16500 -16.8   1.8  320  32 17   7.0   3.9 | -17.4   0.7  315  35 18   7.2   4.0
 16000 -15.7   3.7  325  31 16   7.1   3.9 | -15.8   3.6  320  34 17   7.1   3.9
 15500 -14.2   6.4  325  33 17   7.1   3.9 | -14.8   5.4  320  33 17   7.1   3.9
 15000 -13.1   8.4  325  35 18   6.4   3.5 | -13.7   7.3  320  33 17   6.9   3.8
 14500 -12.3   9.9  325  34 17   6.1   3.3 | -12.7   9.1  320  33 17   6.7   3.7
 14000 -11.4  11.5  325  32 17   6.3   3.4 | -11.8  10.8  320  33 17   6.5   3.6
 13500 -10.4  13.3  325  33 17   6.6   3.6 | -10.9  12.4  320  32 16   6.0   3.3
 13000  -9.4  15.1  320  34 18   6.3   3.5 | -10.0  14.0  320  30 15   6.4   3.5
 12500  -8.6  16.5  320  34 18   5.6   3.1 |  -8.8  16.2  320  30 15   8.2   4.5
 12000  -7.8  18.0  315  35 18   5.7   3.1 |  -7.6  18.3  315  30 16   7.8   4.3
 11500  -6.9  19.6  315  34 18   5.7   3.1 |  -6.7  19.9  315  30 15   5.6   3.1
 11000  -6.1  21.0  315  34 17   5.7   3.1 |  -5.9  21.4  310  29 15   5.9   3.2
 10500  -5.3  22.5  310  32 17   5.9   3.2 |  -4.9  23.2  310  28 15   6.6   3.6
 10250  -4.9  23.2  310  31 16   5.2   2.9 |  -4.5  23.9  310  28 14   6.3   3.4
 10000  -4.4  24.1  305  31 16   7.9   4.3 |  -3.9  25.0  305  28 14   8.7   4.7
  9750  -3.7  25.3  305  28 15   9.0   4.9 |  -3.2  26.2  305  27 14   8.6   4.7
  9500  -3.2  26.2  305  26 14   7.2   4.0 |  -2.7  27.1  305  26 13   6.7   3.7
  9250  -2.6  27.3  305  25 13   7.6   4.2 |  -2.2  28.0  305  24 13   7.2   3.9
  9000  -2.1  28.2  305  23 12   7.0   3.9 |  -1.7  28.9  300  23 12   7.2   3.9
  8750  -1.6  29.1  300  21 11   7.8   4.3 |  -1.1  30.0  300  21 11   7.9   4.3
  8500  -0.9  30.4  300  19 10   8.4   4.6 |  -0.5  31.1  300  20 10   8.2   4.5
  8250  -0.3  31.5  300  17  9   8.4   4.6 |   0.1  32.2  300  18  9   8.3   4.5
  8000   0.3  32.5  295  14  7   8.8   4.8 |   0.7  33.3  300  16  8   8.9   4.9
  7750   1.0  33.8  295  12  6   9.0   4.9 |   1.3  34.3  295  15  7   8.6   4.7
  7500   1.6  34.9  290  10  5   8.8   4.8 |   1.9  35.4  295  13  7   7.8   4.3
  7250   2.3  36.1  290   8  4   9.7   5.3 |   2.5  36.5  290  11  6   8.7   4.8
  7000   3.1  37.6  285   8  4  10.9   6.0 |   3.2  37.8  290  10  5   9.6   5.2
  6750   3.9  39.0  285   7  4   9.3   5.1 |   3.9  39.0  285   9  5   9.3   5.1
  6500   4.5  40.1  285   7  3   9.0   4.9 |   4.6  40.3  280   8  4   9.4   5.1
  6250   5.2  41.4  285   6  3  10.6   5.8 |   5.3  41.5  275   7  4   9.7   5.3
  6000   6.1  43.0  285   6  3  10.9   6.0 |   6.0  42.8  275   6  3  10.0   5.5
  5750   6.9  44.4  285   6  3  10.6   5.8 |   6.8  44.2  270   5  3   9.6   5.3
  5500   7.7  45.9  290   5  3  12.7   7.0 |   7.4  45.3  270   4  2   7.6   4.2
________________________________________________________________________________

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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