Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 301315
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0615 MST Saturday, January 30, 2016

This forecast is for Saturday, January 30, 2016:

If the trigger temperature of 61.1 F/16.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 9 ft/min (0.0 m/s)
   Maximum height of thermals.................. 10508 ft MSL (5223 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... 1315 MST
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................. 6132 ft MSL (847 ft AGL)
Thermal soaring outlook for Sunday 01/31....... Poor

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... Increasing
Height of stable layer (12-18K ft MSL)......... 13645 ft MSL (8360 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 14383 ft MSL (9098 ft AGL)
Wave soaring outlook for Sunday 01/31.......... Fair

Remarks...

Sunrise/Sunset.................... 07:09:25 / 17:15:04 MST
Total possible sunshine........... 10 hr 5 min 38 sec (605 min 38 sec)
Altitude of sun at 12:12:37 MST... 32.63 degrees

Upper air data from rawinsonde observation taken on 01/30/2016 at 0500 MST

Freezing level.................. 11041 ft MSL (5756 ft AGL)
Convective condensation level... 18979 ft MSL (13694 ft AGL)
Lifted condensation level....... 14714 ft MSL (9428 ft AGL)
Lifted index.................... +5.3
K index......................... +6.4

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  -55.2 -67.4   280   62   32   6.7   3.7  106.3 223.4    51.5      M    M
 45000  -48.1 -54.6   290   61   31  -6.0  -3.3   93.7 200.6    47.3      M    M
 40000  -57.5 -71.5   280   64   33 -11.1  -6.1   55.0 131.0    25.2      M    M
 38000  -60.2 -76.4   280   60   31 -12.1  -6.6   42.2 107.9    17.2      M    M
 36000  -61.0 -77.8   275   52   27   7.2   4.0   32.3  90.1    10.8      M    M
 34000  -56.5 -69.7   270   45   23   9.9   5.4   30.5  86.9     9.9      M    M
 32000  -50.6 -59.1   270   43   22   9.9   5.4   30.5  86.8    10.1      M    M
 30000  -45.0 -49.0   275   45   23   9.3   5.1   30.3  86.6    10.3      M    M
 29000  -41.5 -42.7   275   45   23   9.3   5.1   30.0  86.0    10.2      M    M
 28000  -38.7 -37.7   270   44   23   9.3   5.1   29.8  85.7    10.2      M    M
 27000  -35.9 -32.6   270   43   22   9.2   5.0   29.7  85.5    10.2      M    M
 26000  -33.2 -27.8   265   42   22   9.1   5.0   29.5  85.1    10.1      M    M
 25000  -30.5 -22.9   265   41   21   9.1   5.0   29.3  84.8    10.1      M    M
 24000  -27.6 -17.7   260   40   21  10.9   6.0   29.2  84.6    10.2      M    M
 23000  -24.7 -12.5   260   40   21   9.7   5.3   29.3  84.7    10.3      M    M
 22000  -21.9  -7.4   255   41   21   9.2   5.1   29.2  84.5    10.3      M    M
 21000  -19.1  -2.4   260   41   21   9.2   5.1   28.9  84.0    10.2      M    M
 20000  -16.4   2.5   265   41   21   9.2   5.1   28.8  83.8    10.2      M    M
 19500  -15.0   5.0   270   42   21   9.2   5.1   28.6  83.5    10.2      M    M
 19000  -13.6   7.5   270   43   22   9.3   5.1   28.5  83.3    10.1      M    M
 18500  -12.4   9.7   275   44   22   6.5   3.5   28.3  82.9     9.9      M    M
 18000  -11.5  11.3   280   45   23   6.0   3.3   27.6  81.7     9.4      M    M
 17500  -10.6  12.9   280   46   23   6.0   3.3   26.9  80.5     8.8      M    M
 17000   -9.8  14.4   280   46   24   6.1   3.3   26.3  79.3     8.3      M    M
 16500   -8.9  16.0   275   47   24   7.2   4.0   25.7  78.2     7.8      M    M
 16000   -7.6  18.3   275   48   25   8.3   4.6   25.4  77.8     7.6      M    M
 15500   -6.4  20.5   275   49   25   8.3   4.6   25.2  77.4     7.4      M    M
 15000   -5.1  22.8   275   51   26   7.0   3.8   25.0  77.0     7.3      M    M
 14500   -4.4  24.1   275   53   27   2.7   1.5   23.4  74.2     5.9      M    M
 14000   -4.0  24.8   275   53   27   0.6   0.3   22.3  72.2     4.8      M    M
 13500   -4.0  24.8   275   48   25   3.7   2.0   20.7  69.3     3.3      M    M
 13000   -3.3  26.1   275   42   22   4.9   2.7   19.9  67.9     2.6      M    M
 12500   -2.6  27.3   280   37   19   5.1   2.8   19.2  66.5     1.9      M    M
 12000   -1.9  28.6   280   33   17   6.1   3.3   18.5  65.2     1.2      M    M
 11500   -0.8  30.6   275   30   15   6.9   3.8   18.0  64.4     0.8      M    M
 11000    0.2  32.4   275   27   14   7.0   3.8   17.6  63.6     0.4      M    M
 10500    1.2  34.2   275   26   13   7.0   3.8   17.1  62.8    -0.1    403  2.0
 10250    1.8  35.2   275   26   13   7.8   4.3   16.9  62.5    -0.2    379  1.9
 10000    2.4  36.3   275   25   13   7.9   4.3   16.8  62.3    -0.4    354  1.8
  9750    3.0  37.4   275   25   13   8.8   4.8   16.7  62.0    -0.5    329  1.7
  9500    3.7  38.7   275   25   13   9.8   5.4   16.7  62.0    -0.5    300  1.5
  9250    4.4  39.9   270   25   13   9.6   5.3   16.7  62.0    -0.5    271  1.4
  9000    5.1  41.2   270   25   13   9.7   5.3   16.7  62.0    -0.5    242  1.2
  8750    5.9  42.6   270   22   12   9.6   5.3   16.7  62.0    -0.5    213  1.1
  8500    6.6  43.9   265   20   10   9.8   5.4   16.6  62.0    -0.5    184  0.9
  8250    7.3  45.1   265   18    9   9.1   5.0   16.6  61.9    -0.5    155  0.8
  8000    7.9  46.2   260   16    8   7.7   4.2   16.5  61.8    -0.6    129  0.7
  7750    8.5  47.3   260   14    7   7.4   4.1   16.4  61.4    -0.8    105  0.5
  7500    9.0  48.2   265   12    6   7.5   4.1   16.2  61.1    -1.0     81  0.4
  7250    9.6  49.3   265   11    6   7.5   4.1   16.0  60.8    -1.2     57  0.3
  7000   10.1  50.2   270    9    5   7.3   4.0   15.9  60.5    -1.3     33  0.2
  6750   10.7  51.3   270    6    3   8.3   4.5   15.7  60.2    -1.5      9  0.0
  6500   11.3  52.3   280    3    1   4.5   2.5   15.5  59.9    -1.7      M    M
  6250   11.4  52.5   030    1    0   1.4   0.8   14.9  58.8    -2.3      M    M
  6000   10.8  51.4   075    4    2 -28.7 -15.8   13.6  56.4    -3.6      M    M
  5750    7.4  45.3   055    1    0 -51.0 -28.0    9.3  48.7    -7.8     79  0.4
  5500    4.7  40.5   270    3    1 -17.0  -9.3    5.8  42.5   -11.3    153  0.8

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

           01/30/2016 at 0800 MST          |       01/30/2016 at 1100 MST
                                           |
K index... +11.8  LI... +2.5               | K index... +14.2  LI... +2.1
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.0
                                           |
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 -53.1 -63.6  295  31 16   3.8   2.1 | -53.8 -64.8  260  30 15   3.5   1.9
 45000 -47.5 -53.5  280  62 32   4.9   2.7 | -48.5 -55.3  275  68 35   4.4   2.4
 40000 -54.5 -66.1  285  65 34  -4.9  -2.7 | -53.1 -63.6  280  65 33  -3.2  -1.8
 38000 -56.5 -69.7  285  64 33  -0.9  -0.5 | -54.7 -66.5  275  61 31  -2.0  -1.1
 36000 -57.1 -70.8  275  60 31  -1.0  -0.5 | -55.9 -68.6  265  55 28  -2.0  -1.1
 34000 -57.4 -71.3  260  58 30   7.0   3.8 | -57.0 -70.6  250  51 26   5.0   2.7
 32000 -51.3 -60.3  260  54 28  10.2   5.6 | -51.2 -60.2  250  49 25   9.7   5.3
 30000 -45.3 -49.5  255  50 26   9.6   5.3 | -45.4 -49.7  255  47 24   9.2   5.0
 29000 -41.8 -43.2  255  47 24   9.3   5.1 | -42.2 -44.0  255  45 23   8.8   4.8
 28000 -39.0 -38.2  250  45 23   9.3   5.1 | -39.5 -39.1  260  44 22   8.8   4.8
 27000 -36.2 -33.2  245  44 22   9.1   5.0 | -36.9 -34.4  265  42 22   8.8   4.8
 26000 -33.7 -28.7  245  40 21   8.3   4.5 | -34.4 -29.9  265  39 20   8.6   4.7
 25000 -31.3 -24.3  250  37 19   8.3   4.5 | -31.8 -25.2  260  36 19   8.6   4.7
 24000 -28.8 -19.8  250  34 17   8.4   4.6 | -29.3 -20.7  255  33 17   8.7   4.8
 23000 -26.5 -15.7  245  31 16   7.5   4.1 | -27.0 -16.6  250  30 15   7.3   4.0
 22000 -24.3 -11.7  245  29 15   7.5   4.1 | -24.8 -12.6  245  26 13   7.3   4.0
 21000 -22.1  -7.8  240  27 14   7.7   4.2 | -22.7  -8.9  240  23 12   7.3   4.0
 20000 -19.7  -3.5  240  25 13   8.2   4.5 | -20.5  -4.9  240  20 10   7.3   4.0
 19500 -18.5  -1.3  240  24 12   8.2   4.5 | -19.5  -3.1  240  18  9   7.3   4.0
 19000 -17.2   1.0  235  23 12   8.2   4.5 | -18.4  -1.1  240  17  9   7.3   4.0
 18500 -16.0   3.2  235  23 12   8.1   4.4 | -17.3   0.9  240  16  8   7.3   4.0
 18000 -14.7   5.5  235  22 11   9.6   5.3 | -16.2   2.8  240  14  7   7.8   4.3
 17500 -13.3   8.1  235  22 11   9.4   5.2 | -15.0   5.0  245  14  7   7.8   4.3
 17000 -11.9  10.6  240  22 11   9.0   4.9 | -13.9   7.0  250  13  7   8.3   4.5
 16500 -10.6  12.9  245  22 11   8.7   4.8 | -12.6   9.3  255  13  7   8.8   4.8
 16000  -9.3  15.3  250  23 12   8.6   4.7 | -11.2  11.8  265  13  7   8.8   4.8
 15500  -7.5  18.5  255  24 12   7.8   4.3 |  -9.9  14.2  270  15  8   9.3   5.1
 15000  -6.4  20.5  260  25 13   7.5   4.1 |  -7.8  18.0  280  18  9   8.7   4.8
 14500  -5.3  22.5  265  26 13   7.0   3.8 |  -6.7  19.9  285  21 11   7.1   3.9
 14000  -4.3  24.3  270  27 14   7.0   3.8 |  -5.7  21.7  285  24 12   7.2   4.0
 13500  -3.3  26.1  275  30 15   6.7   3.7 |  -4.7  23.5  285  27 14   5.7   3.1
 13000  -2.3  27.9  280  33 17   7.1   3.9 |  -3.9  25.0  285  30 16   5.8   3.2
 12500  -1.5  29.3  280  34 18   4.2   2.3 |  -3.1  26.4  285  33 17   5.9   3.2
 12000  -0.9  30.4  285  35 18   4.3   2.4 |  -2.2  28.0  285  34 18   6.0   3.3
 11500  -0.2  31.6  285  35 18   4.7   2.6 |  -1.4  29.5  285  35 18   4.9   2.7
 11000   0.5  32.9  285  35 18   4.8   2.6 |  -0.7  30.7  285  35 18   4.9   2.7
 10500   1.1  34.0  285  34 18   4.1   2.2 |  -0.1  31.8  285  34 18   4.4   2.4
 10250   1.4  34.5  285  33 17   4.0   2.2 |   0.2  32.4  285  33 17   4.3   2.4
 10000   1.7  35.1  285  32 17   3.9   2.1 |   0.5  32.9  285  32 17   4.2   2.3
  9750   1.9  35.4  285  31 16   4.1   2.3 |   0.8  33.4  285  31 16   4.5   2.5
  9500   2.2  36.0  285  29 15   4.3   2.4 |   1.2  34.2  285  28 14   4.9   2.7
  9250   2.6  36.7  285  26 13   4.7   2.6 |   1.5  34.7  280  24 12   5.0   2.7
  9000   2.9  37.2  280  23 12   3.4   1.9 |   1.9  35.4  280  21 11   4.7   2.6
  8750   3.1  37.6  280  21 11   4.6   2.5 |   2.3  36.1  280  18  9   6.9   3.8
  8500   3.6  38.5  275  18  9   6.5   3.6 |   2.9  37.2  280  16  8   8.5   4.7
  8250   4.0  39.2  270  15  8   6.5   3.6 |   3.5  38.3  275  13  7   8.7   4.8
  8000   4.5  40.1  265  12  6   4.6   2.5 |   4.1  39.4  270  10  5   6.2   3.4
  7750   4.8  40.6  255  10  5   5.7   3.1 |   4.5  40.1  260   8  4   6.5   3.6
  7500   5.4  41.7  240  10  5   8.6   4.7 |   5.2  41.4  255   7  4   9.4   5.2
  7250   6.0  42.8  230   9  5   7.9   4.3 |   5.8  42.4  240   7  3   8.5   4.7
  7000   6.6  43.9  215   9  5   7.8   4.3 |   6.5  43.7  230   6  3   9.3   5.1
  6750   7.2  45.0  205  10  5   8.6   4.7 |   7.2  45.0  220   6  3   9.6   5.3
  6500   7.9  46.2  205  10  5   9.9   5.5 |   7.9  46.2  220   6  3   9.6   5.3
  6250   8.6  47.5  200  10  5   8.1   4.4 |   8.6  47.5  215   7  3   8.6   4.7
  6000   8.8  47.8  195  11  6  -5.0  -2.7 |   9.0  48.2  210   7  3   2.3   1.3
  5750   7.6  45.7  195  13  6 -27.9 -15.3 |   8.9  48.0  205   7  4  -5.8  -3.2
  5500   4.9  40.8  195  10  5 -42.1 -23.1 |   8.3  46.9  200   6  3  -8.9  -4.9

           01/30/2016 at 1400 MST          |       01/30/2016 at 1700 MST
                                           |
K index... +15.6  LI... +2.4               | K index... +20.2  LI... +1.6
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... -1.2
                                           |
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 -54.0 -65.2  275  40 20   4.4   2.4 | -54.1 -65.4  285  37 19   4.0   2.2
 45000 -47.3 -53.1  280  64 33   5.2   2.9 | -48.1 -54.6  280  66 34   4.5   2.5
 40000 -51.0 -59.8  275  68 35  -2.7  -1.5 | -49.2 -56.6  275  67 35  -1.0  -0.5
 38000 -52.7 -62.9  270  67 34  -2.8  -1.5 | -50.4 -58.7  270  65 34  -4.7  -2.6
 36000 -54.3 -65.7  260  63 32  -2.8  -1.5 | -53.3 -63.9  260  61 31  -4.7  -2.6
 34000 -56.0 -68.8  250  60 31   0.1   0.0 | -56.1 -69.0  250  59 30  -3.8  -2.1
 32000 -51.6 -60.9  255  54 28   7.8   4.3 | -52.1 -61.8  250  55 28   7.7   4.2
 30000 -47.0 -52.6  260  47 24   8.4   4.6 | -47.5 -53.5  245  52 27   8.3   4.6
 29000 -43.6 -46.5  260  45 23   9.1   5.0 | -44.7 -48.5  245  49 25   9.5   5.2
 28000 -40.9 -41.6  265  44 23   9.1   5.0 | -41.2 -42.2  245  46 23   9.5   5.2
 27000 -38.2 -36.8  265  43 22   9.1   5.0 | -38.4 -37.1  245  43 22   9.6   5.3
 26000 -35.5 -31.9  260  40 21   8.7   4.8 | -35.8 -32.4  250  42 22   8.4   4.6
 25000 -32.9 -27.2  255  37 19   8.7   4.8 | -33.3 -27.9  250  43 22   8.4   4.6
 24000 -30.3 -22.5  250  35 18   8.8   4.8 | -30.8 -23.4  250  43 22   8.4   4.6
 23000 -28.0 -18.4  250  31 16   7.1   3.9 | -28.4 -19.1  255  44 23   8.0   4.4
 22000 -25.9 -14.6  245  27 14   7.1   3.9 | -26.0 -14.8  260  45 23   8.0   4.4
 21000 -23.8 -10.8  240  23 12   7.0   3.8 | -23.6 -10.5  265  47 24   8.1   4.4
 20000 -21.5  -6.7  240  21 11   8.2   4.5 | -21.5  -6.7  270  46 24   6.9   3.8
 19500 -20.3  -4.5  240  20 10   8.1   4.5 | -20.5  -4.9  270  45 23   6.9   3.8
 19000 -19.1  -2.4  245  19 10   8.1   4.5 | -19.5  -3.1  270  44 23   6.9   3.8
 18500 -17.9  -0.2  245  18  9   8.1   4.4 | -18.4  -1.1  270  43 22   6.9   3.8
 18000 -16.6   2.1  250  18  9   8.9   4.9 | -17.4   0.7  265  42 21   7.2   3.9
 17500 -15.3   4.5  255  20 10   8.9   4.9 | -16.3   2.7  265  42 22   7.3   4.0
 17000 -13.9   7.0  260  22 11   8.4   4.6 | -15.3   4.5  270  42 22   7.2   4.0
 16500 -12.8   9.0  270  25 13   7.3   4.0 | -14.2   6.4  270  44 23   6.9   3.8
 16000 -11.7  10.9  275  29 15   7.4   4.1 | -13.2   8.2  270  46 24   7.0   3.8
 15500 -10.7  12.7  275  32 17   6.4   3.5 | -12.3   9.9  270  48 25   5.8   3.2
 15000  -9.3  15.3  280  37 19   6.4   3.5 | -11.0  12.2  270  48 25   5.8   3.2
 14500  -8.4  16.9  280  39 20   5.9   3.2 | -10.2  13.6  270  47 24   5.3   2.9
 14000  -7.6  18.3  280  41 21   5.9   3.3 |  -9.5  14.9  270  45 23   5.3   2.9
 13500  -6.7  19.9  280  42 22   5.9   3.2 |  -8.7  16.3  270  41 21   5.7   3.1
 13000  -5.9  21.4  280  42 22   5.9   3.2 |  -7.9  17.8  265  35 18   5.6   3.1
 12500  -5.0  23.0  280  41 21   5.9   3.2 |  -7.0  19.4  265  29 15   6.9   3.8
 12000  -4.2  24.4  280  38 20   5.9   3.3 |  -6.0  21.2  260  24 12   7.0   3.8
 11500  -3.3  26.1  280  35 18   5.8   3.2 |  -4.9  23.2  255  19 10   7.8   4.3
 11000  -2.5  27.5  280  30 15   5.8   3.2 |  -3.7  25.3  245  15  8   7.9   4.3
 10500  -1.6  29.1  280  24 13   6.1   3.3 |  -2.5  27.5  230  12  6   9.4   5.2
 10250  -1.2  29.8  280  21 11   6.3   3.4 |  -1.8  28.8  225  11  6   9.7   5.3
 10000  -0.7  30.7  280  19 10   6.2   3.4 |  -1.1  30.0  220  11  5   9.1   5.0
  9750  -0.2  31.6  280  16  8   7.2   3.9 |  -0.4  31.3  215  10  5   9.7   5.3
  9500   0.3  32.5  280  13  7   8.2   4.5 |   0.4  32.7  210  10  5  10.4   5.7
  9250   1.0  33.8  280  11  5   9.2   5.1 |   1.2  34.2  210  10  5  11.6   6.4
  9000   1.6  34.9  275   8  4   6.1   3.3 |   2.0  35.6  210   9  5   7.9   4.3
  8750   2.0  35.6  265   6  3   6.7   3.7 |   2.5  36.5  205   9  5   7.6   4.2
  8500   2.7  36.9  255   4  2  10.4   5.7 |   3.2  37.8  205   8  4  11.3   6.2
  8250   3.4  38.1  235   3  1  10.3   5.6 |   4.0  39.2  205   8  4  11.6   6.3
  8000   4.1  39.4  195   3  1   8.1   4.4 |   4.9  40.8  205   7  4   9.1   5.0
  7750   4.7  40.5  170   3  2   8.0   4.4 |   5.4  41.7  200   7  3   7.1   3.9
  7500   5.4  41.7  170   3  2  10.4   5.7 |   6.0  42.8  195   5  2   8.0   4.4
  7250   6.1  43.0  165   3  2   9.9   5.4 |   6.6  43.9  190   3  2   8.4   4.6
  7000   6.9  44.4  165   3  2   9.6   5.3 |   7.2  45.0  160   2  1   5.8   3.2
  6750   7.6  45.7  160   3  2   9.4   5.1 |   7.4  45.3  080   3  1   2.4   1.3
  6500   8.3  46.9  155   3  2   9.6   5.3 |   7.6  45.7  065   5  2   2.5   1.4
  6250   9.0  48.2  155   3  2   9.6   5.3 |   7.8  46.0  060   7  4   2.9   1.6
  6000   9.7  49.5  150   3  2   8.8   4.8 |   8.0  46.4  055   9  5   0.4   0.2
  5750  10.3  50.5  145   3  1   9.9   5.4 |   7.8  46.0  055  10  5  -2.4  -1.3
  5500  11.2  52.2  140   3  1  14.1   7.7 |   7.5  45.5  055   7  4  -0.4  -0.2
________________________________________________________________________________

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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