Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201213
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0513 MST Friday, February 20, 2015

This forecast is for Friday, February 20, 2015:

If the trigger temperature of 56.9 F/13.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7114 ft MSL (1829 ft AGL)

Forecast maximum temperature................... 53.0 F/12.1 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................. 6323 ft MSL (1038 ft AGL)
Thermal soaring outlook for Saturday 02/21..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 14377 ft MSL (9092 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 16342 ft MSL (11057 ft AGL)
Wave soaring outlook for Saturday 02/21........ Poor

Remarks...

Sunrise/Sunset.................... 06:45:29 / 17:40:05 MST
Total possible sunshine........... 10 hr 54 min 35 sec (654 min 35 sec)
Altitude of sun at 12:13:04 MST... 39.44 degrees

Upper air data from rawinsonde observation taken on 02/20/2015 at 0500 MST

Freezing level.................. 9948 ft MSL (4663 ft AGL)
Convective condensation level... 16698 ft MSL (11413 ft AGL)
Lifted condensation level....... 14201 ft MSL (8915 ft AGL)
Lifted index.................... +5.9
K index......................... -2.3

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  -59.1 -74.4   285   60   31  -4.7  -2.6  102.9 217.2    51.9      M    M
 45000  -57.8 -72.0   285   84   43   2.8   1.5   80.2 176.4    41.8      M    M
 40000  -55.5 -67.9   280   78   40  -0.8  -0.5   59.7 139.4    31.4      M    M
 38000  -58.6 -73.5   285   92   47   0.1   0.1   46.2 115.1    23.2      M    M
 36000  -59.8 -75.6   280   91   47   3.6   1.9   35.9  96.7    16.8      M    M
 34000  -55.9 -68.6   275   78   40   7.1   3.9   33.1  91.5    15.2      M    M
 32000  -51.5 -60.7   275   72   37   9.1   5.0   31.1  87.9    14.1      M    M
 30000  -47.0 -52.6   270   66   34   6.4   3.5   29.3  84.7    13.2      M    M
 29000  -44.7 -48.5   270   63   33   7.7   4.2   28.4  83.1    12.6      M    M
 28000  -41.7 -43.1   275   60   31   8.2   4.5   27.6  81.7    12.2      M    M
 27000  -39.2 -38.6   275   57   29   8.5   4.6   27.0  80.7    12.0      M    M
 26000  -36.6 -33.9   280   54   28   8.2   4.5   26.6  79.8    11.7      M    M
 25000  -34.2 -29.6   280   52   27   8.1   4.5   26.0  78.8    11.4      M    M
 24000  -32.2 -26.0   270   46   24   4.0   2.2   24.8  76.7    10.6      M    M
 23000  -30.2 -22.4   275   40   21   8.1   4.4   23.7  74.7     9.8      M    M
 22000  -27.6 -17.7   280   40   21   8.9   4.9   23.3  73.9     9.6      M    M
 21000  -24.9 -12.8   285   41   21   8.9   4.9   23.0  73.3     9.4      M    M
 20000  -22.4  -8.3   290   42   22   7.2   4.0   22.6  72.7     9.2      M    M
 19500  -21.3  -6.3   290   42   21   7.4   4.1   22.2  71.9     8.9      M    M
 19000  -20.2  -4.4   295   41   21   7.7   4.2   21.8  71.2     8.6      M    M
 18500  -19.0  -2.2   295   41   21   6.8   3.7   21.5  70.7     8.4      M    M
 18000  -18.1  -0.6   295   42   22   6.2   3.4   20.8  69.5     7.8      M    M
 17500  -17.2   1.0   295   44   23   5.7   3.1   20.2  68.4     7.3      M    M
 17000  -16.4   2.5   290   46   24   2.5   1.4   19.5  67.1     6.7      M    M
 16500  -15.8   3.6   290   48   25   8.3   4.5   18.5  65.3     5.9      M    M
 16000  -14.6   5.7   290   51   26   7.9   4.3   18.2  64.7     5.7      M    M
 15500  -13.4   7.9   290   49   25   8.0   4.4   17.9  64.1     5.5      M    M
 15000  -12.1  10.2   290   47   24   8.7   4.8   17.6  63.8     5.3      M    M
 14500  -10.9  12.4   290   45   23   5.3   2.9   17.4  63.3     5.1      M    M
 14000  -10.4  13.3   290   42   21   5.8   3.2   15.7  60.3     3.4      M    M
 13500   -9.5  14.9   285   36   19   6.1   3.4   15.1  59.2     2.9      M    M
 13000   -8.5  16.7   285   31   16   8.4   4.6   14.6  58.3     2.4      M    M
 12500   -7.1  19.2   290   28   15   9.4   5.1   14.6  58.3     2.4      M    M
 12000   -5.7  21.7   290   26   13   9.5   5.2   14.6  58.2     2.4      M    M
 11500   -4.3  24.3   290   26   14   9.5   5.2   14.5  58.0     2.3      M    M
 11000   -2.8  27.0   295   26   14   9.5   5.2   14.4  57.9     2.3      M    M
 10500   -1.4  29.5   295   27   14   9.5   5.2   14.4  57.8     2.2      M    M
 10250   -0.7  30.7   295   27   14   9.5   5.2   14.3  57.8     2.2      M    M
 10000   -0.0  32.0   295   27   14   9.3   5.1   14.3  57.8     2.2      M    M
  9750    0.7  33.3   295   26   13   9.0   5.0   14.3  57.7     2.2      M    M
  9500    1.3  34.3   295   24   12   9.0   4.9   14.2  57.6     2.1      M    M
  9250    2.0  35.6   295   22   12   9.0   4.9   14.2  57.5     2.1      M    M
  9000    2.7  36.9   295   21   11   9.0   5.0   14.1  57.4     2.0      M    M
  8750    3.4  38.1   300   18    9   9.0   4.9   14.1  57.3     2.0      M    M
  8500    4.0  39.2   305   15    8   9.2   5.1   14.0  57.2     1.9      M    M
  8250    4.6  40.3   310   12    6   6.4   3.5   13.9  57.0     1.8      M    M
  8000    5.0  41.0   320   10    5   4.0   2.2   13.5  56.3     1.4      M    M
  7750    5.3  41.5   325    9    5   4.6   2.5   13.1  55.5     1.0      M    M
  7500    5.6  42.1   335    8    4   4.5   2.5   12.7  54.8     0.6      M    M
  7250    6.0  42.8   345    7    4   4.3   2.4   12.3  54.1     0.2      M    M
  7000    6.3  43.3   360    7    4   5.3   2.9   11.9  53.4    -0.2     76  0.4
  6750    6.6  43.9   040    8    4   1.5   0.8   11.5  52.6    -0.6     59  0.3
  6500    6.3  43.3   065   11    6 -10.0  -5.5   10.4  50.7    -1.6     61  0.3
  6250    5.3  41.5   080   16    8 -14.3  -7.9    8.6  47.5    -3.4     84  0.4
  6000    4.3  39.7   085   21   11 -14.2  -7.8    6.9  44.4    -5.2    107  0.5
  5750    3.2  37.8   085   16    8 -10.4  -5.7    5.1  41.2    -6.9    131  0.7
  5500    2.8  37.0   085   11    6   0.4   0.2    4.0  39.2    -8.1    136  0.7

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

           02/20/2015 at 0800 MST          |       02/20/2015 at 1100 MST
                                           |
K index... +9.2  LI... +275.7              | K index... +10.8  LI... +274.7
CAPE... 0.0  CIN... -0.7                   | 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 -57.8 -72.0  295  43 22   0.8   0.4 | -56.5 -69.7  285  48 25   1.0   0.5
 45000 -56.6 -69.9  280  67 34   0.8   0.4 | -55.1 -67.2  280  68 35   0.9   0.5
 40000 -57.1 -70.8  285  78 40  -0.5  -0.3 | -57.0 -70.6  280  73 38  -1.6  -0.9
 38000 -57.2 -71.0  285  82 42   0.9   0.5 | -57.7 -71.9  280  75 39   2.6   1.4
 36000 -56.6 -69.9  280  87 45   0.9   0.5 | -56.2 -69.2  275  86 44   2.2   1.2
 34000 -56.1 -69.0  280  93 48   3.2   1.8 | -54.8 -66.6  275  95 49   2.6   1.4
 32000 -52.3 -62.1  275  82 42   6.5   3.5 | -52.1 -61.8  270  87 45   4.8   2.6
 30000 -48.4 -55.1  275  71 36   7.2   4.0 | -49.2 -56.6  265  78 40   5.7   3.1
 29000 -46.1 -51.0  275  67 35   7.5   4.1 | -47.0 -52.6  270  74 38   7.2   3.9
 28000 -43.9 -47.0  275  64 33   7.5   4.1 | -44.9 -48.8  270  70 36   7.2   4.0
 27000 -41.6 -42.9  275  61 31   7.5   4.1 | -42.7 -44.9  270  66 34   7.2   4.0
 26000 -39.3 -38.7  275  58 30   8.1   4.4 | -40.3 -40.5  275  62 32   9.0   4.9
 25000 -36.9 -34.4  275  56 29   8.1   4.4 | -37.6 -35.7  270  58 30   9.1   5.0
 24000 -34.4 -29.9  275  53 27   8.1   4.4 | -34.8 -30.6  270  55 28   9.0   4.9
 23000 -32.0 -25.6  275  51 26   7.9   4.3 | -32.3 -26.1  270  51 27   7.6   4.2
 22000 -29.7 -21.5  275  48 25   7.9   4.3 | -30.0 -22.0  270  49 25   7.6   4.2
 21000 -27.3 -17.1  280  45 23   7.9   4.3 | -27.8 -18.0  270  47 24   7.6   4.2
 20000 -24.9 -12.8  280  43 22   8.0   4.4 | -25.5 -13.9  270  46 24   7.8   4.3
 19500 -23.7 -10.7  280  42 22   8.0   4.4 | -24.3 -11.7  275  46 24   7.8   4.3
 19000 -22.5  -8.5  280  41 21   8.0   4.4 | -23.1  -9.6  275  46 24   7.8   4.3
 18500 -21.3  -6.3  280  40 21   8.0   4.4 | -21.9  -7.4  275  46 24   7.8   4.3
 18000 -19.5  -3.1  280  39 20   8.0   4.4 | -20.2  -4.4  280  45 23   7.7   4.2
 17500 -18.4  -1.1  280  37 19   7.9   4.4 | -19.0  -2.2  280  44 22   7.7   4.2
 17000 -17.1   1.2  280  36 19   8.2   4.5 | -17.9  -0.2  280  42 22   7.6   4.2
 16500 -15.9   3.4  280  35 18   8.2   4.5 | -16.8   1.8  280  40 21   7.6   4.2
 16000 -14.7   5.5  280  34 17   8.1   4.5 | -15.6   3.9  280  39 20   8.1   4.5
 15500 -13.5   7.7  280  32 16   8.1   4.4 | -14.4   6.1  275  37 19   8.6   4.7
 15000 -12.3   9.9  285  30 16   8.0   4.4 | -13.1   8.4  275  35 18   8.6   4.7
 14500 -11.1  12.0  285  29 15   7.9   4.3 | -11.8  10.8  275  34 17   8.3   4.6
 14000  -9.9  14.2  285  28 14   7.8   4.3 | -10.6  12.9  275  32 16   8.4   4.6
 13500  -8.8  16.2  290  27 14   7.7   4.2 |  -9.4  15.1  280  31 16   8.1   4.4
 13000  -7.6  18.3  295  27 14   7.7   4.2 |  -8.2  17.2  280  32 16   8.3   4.6
 12500  -6.5  20.3  295  26 14   8.0   4.4 |  -7.1  19.2  280  30 16   6.8   3.7
 12000  -5.3  22.5  300  25 13   8.0   4.4 |  -6.1  21.0  285  28 14   7.0   3.9
 11500  -4.2  24.4  300  26 13   7.1   3.9 |  -5.2  22.6  285  26 13   6.1   3.3
 11000  -3.1  26.4  300  28 14   7.2   3.9 |  -4.3  24.3  285  25 13   6.3   3.5
 10500  -2.1  28.2  300  28 14   6.8   3.8 |  -3.4  25.9  290  23 12   5.1   2.8
 10250  -1.6  29.1  300  27 14   6.6   3.6 |  -3.0  26.6  290  21 11   4.6   2.5
 10000  -1.1  30.0  300  27 14   9.3   5.1 |  -2.7  27.1  295  19 10   7.4   4.1
  9750  -0.3  31.5  300  27 14   8.8   4.8 |  -2.0  28.4  295  18  9   7.0   3.9
  9500   0.2  32.4  300  26 13   6.0   3.3 |  -1.7  28.9  300  16  8   4.2   2.3
  9250   0.7  33.3  300  25 13   7.2   4.0 |  -1.3  29.7  300  14  7   4.7   2.6
  9000   1.2  34.2  305  23 12   5.0   2.8 |  -1.0  30.2  305  12  6   5.4   3.0
  8750   1.4  34.5  305  20 10   4.6   2.5 |  -0.5  31.1  310  11  5   5.4   3.0
  8500   1.9  35.4  305  19 10   6.1   3.4 |  -0.2  31.6  315   9  5   4.5   2.5
  8250   2.3  36.1  305  19 10   6.0   3.3 |   0.2  32.4  320   7  4   4.6   2.5
  8000   2.8  37.0  305  18  9   4.7   2.6 |   0.5  32.9  325   6  3   5.2   2.9
  7750   3.0  37.4  305  15  8   2.3   1.3 |   1.0  33.8  340   4  2   5.6   3.1
  7500   3.1  37.6  305  13  7   2.0   1.1 |   1.4  34.5  350   3  2   5.1   2.8
  7250   3.3  37.9  310  11  5   2.3   1.3 |   1.8  35.2  015   2  1   5.4   3.0
  7000   3.5  38.3  310   8  4   3.0   1.7 |   2.2  36.0  050   2  1   8.2   4.5
  6750   3.7  38.7  320   5  2   3.1   1.7 |   2.9  37.2  080   2  1   7.7   4.2
  6500   4.0  39.2  340   2  1   4.4   2.4 |   3.4  38.1  095   3  2   6.6   3.6
  6250   4.2  39.6  075   2  1  -1.5  -0.8 |   3.8  38.8  105   4  2   3.8   2.1
  6000   3.7  38.7  125   2  1  -6.7  -3.7 |   3.9  39.0  105   4  2   0.6   0.3
  5750   3.3  37.9  150   3  2  -6.3  -3.4 |   3.9  39.0  110   4  2  -1.2  -0.7
  5500   2.1  35.8  190   5  3 -29.1 -16.0 |   3.5  38.3  120   3  1  -5.7  -3.1

           02/20/2015 at 1400 MST          |       02/20/2015 at 1700 MST
                                           |
K index... +22.7  LI... +272.8             | K index... +15.6  LI... +273.1
CAPE... +5.6  CIN... -48.7                 | CAPE... 0.0  CIN... -46.6
                                           |
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 -55.9 -68.6  285  47 24   1.4   0.8 | -56.4 -69.5  290  49 25   2.2   1.2
 45000 -53.8 -64.8  285  60 31   1.4   0.8 | -53.1 -63.6  285  56 29   2.2   1.2
 40000 -52.6 -62.7  280  62 32   0.7   0.4 | -50.9 -59.6  285  65 34   1.3   0.7
 38000 -52.2 -62.0  280  64 33  -0.6  -0.3 | -50.2 -58.4  285  70 36  -1.6  -0.9
 36000 -52.5 -62.5  275  82 42  -0.5  -0.2 | -51.3 -60.3  285  83 43  -1.8  -1.0
 34000 -52.8 -63.0  275 103 53  -0.9  -0.5 | -52.5 -62.5  280  97 50  -2.1  -1.1
 32000 -51.0 -59.8  275 101 52   3.7   2.0 | -50.5 -58.9  280  94 49   4.5   2.5
 30000 -48.8 -55.8  275  95 49   3.6   2.0 | -47.8 -54.0  280  88 46   4.6   2.5
 29000 -47.5 -53.5  275  88 45   4.5   2.5 | -46.7 -52.1  280  79 41   3.3   1.8
 28000 -46.1 -51.0  275  80 41   4.5   2.5 | -45.7 -50.3  280  67 35   3.3   1.8
 27000 -44.8 -48.6  275  73 37   4.6   2.5 | -44.7 -48.5  275  55 28   3.3   1.8
 26000 -43.0 -45.4  275  65 34   8.6   4.7 | -43.4 -46.1  275  44 23   7.6   4.2
 25000 -40.5 -40.9  275  58 30   8.4   4.6 | -41.3 -42.3  265  38 20   7.1   3.9
 24000 -38.0 -36.4  275  51 26   8.4   4.6 | -39.2 -38.6  260  33 17   7.1   3.9
 23000 -35.4 -31.7  270  46 24   8.8   4.8 | -37.0 -34.6  250  28 15   8.4   4.6
 22000 -32.8 -27.0  270  45 23   8.7   4.8 | -34.5 -30.1  260  27 14   8.3   4.5
 21000 -30.2 -22.4  265  44 23   8.8   4.8 | -32.0 -25.6  270  27 14   8.3   4.5
 20000 -27.8 -18.0  265  43 22   7.8   4.3 | -29.6 -21.3  280  26 13   7.8   4.3
 19500 -26.6 -15.9  270  43 22   7.8   4.3 | -28.5 -19.3  280  26 13   7.8   4.3
 19000 -25.4 -13.7  270  42 22   7.8   4.3 | -27.3 -17.1  280  25 13   7.8   4.3
 18500 -24.3 -11.7  270  42 22   7.9   4.3 | -26.1 -15.0  285  25 13   7.8   4.3
 18000 -22.5  -8.5  270  41 21   8.1   4.5 | -25.0 -13.0  285  24 12   7.8   4.3
 17500 -21.3  -6.3  270  40 21   8.1   4.4 | -23.2  -9.8  290  25 13   7.9   4.3
 17000 -20.1  -4.2  265  40 20   8.0   4.4 | -22.1  -7.8  295  25 13   7.7   4.2
 16500 -19.0  -2.2  265  38 20   7.9   4.3 | -20.9  -5.6  295  28 14   7.7   4.2
 16000 -17.8  -0.0  265  37 19   8.1   4.5 | -19.8  -3.6  300  31 16   7.7   4.3
 15500 -16.5   2.3  265  36 19   8.6   4.7 | -18.6  -1.5  300  33 17   8.1   4.5
 15000 -15.3   4.5  265  35 18   8.6   4.7 | -17.4   0.7  305  34 18   8.1   4.5
 14500 -14.0   6.8  265  33 17   8.7   4.8 | -16.2   2.8  305  34 18   7.9   4.3
 14000 -12.7   9.1  265  31 16   8.6   4.7 | -15.0   5.0  310  33 17   7.9   4.3
 13500 -11.4  11.5  265  28 14   9.2   5.0 | -13.8   7.2  315  33 17   8.0   4.4
 13000 -10.0  14.0  265  24 12   9.3   5.1 | -12.6   9.3  315  32 17   8.1   4.4
 12500  -8.8  16.2  265  21 11   7.1   3.9 | -11.5  11.3  315  31 16   7.4   4.1
 12000  -7.8  18.0  270  19 10   7.2   3.9 | -10.4  13.3  320  29 15   7.3   4.0
 11500  -6.8  19.8  270  16  8   5.9   3.2 |  -9.2  15.4  320  27 14   8.3   4.5
 11000  -5.9  21.4  265  11  6   5.8   3.2 |  -8.0  17.6  320  27 14   8.4   4.6
 10500  -5.0  23.0  260   8  4   6.4   3.5 |  -6.8  19.8  320  26 14   7.8   4.3
 10250  -4.5  23.9  265   6  3   6.3   3.4 |  -6.3  20.7  320  26 13   7.4   4.1
 10000  -4.0  24.8  265   5  3   7.1   3.9 |  -5.7  21.7  320  25 13   8.9   4.9
  9750  -3.5  25.7  265   4  2   7.5   4.1 |  -5.0  23.0  320  25 13   9.0   5.0
  9500  -2.9  26.8  270   3  1   6.9   3.8 |  -4.4  24.1  315  25 13   7.6   4.2
  9250  -2.4  27.7  280   1  1   7.3   4.0 |  -3.8  25.2  315  25 13   8.3   4.6
  9000  -1.9  28.6  340   1  0   6.3   3.5 |  -3.2  26.2  310  24 13   7.0   3.8
  8750  -1.4  29.5  350   2  1   6.8   3.8 |  -2.8  27.0  310  24 12   6.6   3.6
  8500  -0.8  30.6  015   2  1   8.1   4.5 |  -2.2  28.0  310  23 12   7.6   4.2
  8250  -0.2  31.6  035   2  1   7.6   4.1 |  -1.7  28.9  305  22 12   7.2   3.9
  8000   0.4  32.7  050   3  1   8.6   4.7 |  -1.2  29.8  300  22 11   8.1   4.4
  7750   1.0  33.8  050   3  2   8.5   4.6 |  -0.6  30.9  300  20 10   6.4   3.5
  7500   1.6  34.9  050   4  2   7.5   4.1 |  -0.3  31.5  295  18  9   4.5   2.5
  7250   2.2  36.0  050   4  2   7.7   4.2 |   0.1  32.2  295  17  9   5.0   2.7
  7000   2.8  37.0  050   5  2   8.3   4.6 |   0.4  32.7  290  16  8   3.9   2.1
  6750   3.4  38.1  045   5  3   8.2   4.5 |   0.6  33.1  285  14  7   3.8   2.1
  6500   4.0  39.2  045   6  3   7.7   4.2 |   0.9  33.6  280  11  6   3.4   1.9
  6250   4.5  40.1  040   6  3   7.2   4.0 |   1.1  34.0  280   9  5   5.9   3.2
  6000   4.9  40.8  035   6  3   6.2   3.4 |   1.7  35.1  275   7  4   8.9   4.9
  5750   5.2  41.4  025   6  3   7.3   4.0 |   2.3  36.1  270   6  3   8.4   4.6
  5500   5.8  42.4  020   5  3  11.0   6.0 |   2.9  37.2  265   4  2   8.6   4.7
________________________________________________________________________________

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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