Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 221340
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0640 MST Wednesday, February 22, 2017

This forecast is for Wednesday, February 22, 2017:

If the trigger temperature of 60.3 F/15.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 961 ft/min (4.9 m/s)
   Maximum height of thermals.................. 15750 ft MSL (10465 ft AGL)

Forecast maximum temperature................... 66.0 F/19.3 C
Time of trigger temperature.................... 1100 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9366 ft MSL (4081 ft AGL)
Thermal soaring outlook for Thursday 02/23..... Poor

Wave Soaring Index............................. Excellent
Wave Soaring Index trend (to 1700 MST)......... Becoming fair
Height of stable layer (12-18K ft MSL)......... 15887 ft MSL (10602 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 25256 ft MSL (19971 ft AGL)
Wave soaring outlook for Thursday 02/23........ Good

Remarks...

Sunrise/Sunset.................... 06:41:55 / 17:43:53 MST
Total possible sunshine........... 11 hr 1 min 59 sec (661 min 59 sec)
Altitude of sun at 12:12:54 MST... 40.23 degrees

Upper air data from rawinsonde observation taken on 02/22/2017 at 0500 MST

Freezing level.................. 10700 ft MSL (5415 ft AGL)
Convective condensation level... 18931 ft MSL (13646 ft AGL)
Lifted condensation level....... 17184 ft MSL (11898 ft AGL)
Lifted index.................... +3.5
K index......................... +4.0

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  -62.9 -81.2   270  102   52  -3.3  -1.8   94.8 202.6    43.4      M    M
 45000  -63.8 -82.8   260   90   46   4.3   2.3   68.5 155.4    30.4      M    M
 40000  -57.6 -71.7   260   77   40   4.1   2.3   54.7 130.5    23.6      M    M
 38000  -55.4 -67.7   260   70   36   3.1   1.7   49.4 120.8    20.6      M    M
 36000  -53.5 -64.3   260   62   32   3.1   1.7   43.5 110.3    17.1      M    M
 34000  -51.2 -60.2   260   59   30   4.8   2.7   37.7  99.8    13.4      M    M
 32000  -47.6 -53.7   265   63   32   7.2   4.0   34.5  94.1    11.4      M    M
 30000  -43.4 -46.1   270   66   34   6.5   3.6   32.4  90.4    10.2      M    M
 29000  -41.4 -42.5   270   68   35   6.5   3.6   31.0  87.9     9.3      M    M
 28000  -39.4 -38.9   270   70   36   6.5   3.6   29.8  85.6     8.4      M    M
 27000  -37.3 -35.1   265   72   37   8.9   4.9   28.9  84.0     7.8      M    M
 26000  -34.7 -30.5   265   74   38   8.7   4.8   28.5  83.2     7.6      M    M
 25000  -32.1 -25.8   265   76   39   8.7   4.8   28.1  82.7     7.4      M    M
 24000  -29.5 -21.1   270   75   39   8.4   4.6   27.7  81.9     7.1      M    M
 23000  -27.3 -17.1   270   75   39   7.0   3.8   26.7  80.0     6.4      M    M
 22000  -25.2 -13.4   270   75   39   7.0   3.9   25.7  78.2     5.6      M    M
 21000  -22.9  -9.2   270   75   39   8.5   4.7   25.0  77.0     5.1      M    M
 20000  -20.3  -4.5   270   75   39   8.6   4.7   24.6  76.3     4.8      M    M
 19500  -19.0  -2.2   270   73   38   8.6   4.7   24.4  75.9     4.7      M    M
 19000  -17.8  -0.0   275   71   37   8.5   4.7   24.1  75.4     4.5      M    M
 18500  -16.5   2.3   275   69   36   7.6   4.2   23.9  75.1     4.3      M    M
 18000  -15.5   4.1   275   67   35   5.8   3.2   23.3  73.9     3.8      M    M
 17500  -14.7   5.5   275   65   33   5.8   3.2   22.6  72.6     3.2      M    M
 17000  -13.8   7.2   275   63   32   5.8   3.2   21.9  71.4     2.6      M    M
 16500  -12.4   9.7   275   60   31   5.3   2.9   20.9  69.7     1.8      M    M
 16000  -11.8  10.8   275   57   29  -8.6  -4.7   20.1  68.2     1.1      M    M
 15500  -12.4   9.7   275   52   27  10.5   5.8   17.8  64.1    -1.1    951  4.8
 15000  -11.4  11.5   270   47   24   7.1   3.9   17.4  63.3    -1.5    905  4.6
 14500  -10.2  13.6   270   43   22   9.4   5.1   17.1  62.9    -1.8    854  4.3
 14000   -8.9  16.0   265   39   20   9.1   5.0   17.1  62.7    -1.9    799  4.1
 13500   -7.5  18.5   265   36   18   9.1   5.0   16.9  62.5    -2.0    743  3.8
 13000   -6.1  21.0   265   33   17   9.1   5.0   16.8  62.3    -2.1    688  3.5
 12500   -4.8  23.4   260   30   16   9.1   5.0   16.8  62.2    -2.2    632  3.2
 12000   -3.4  25.9   260   28   14   9.1   5.0   16.7  62.0    -2.3    577  2.9
 11500   -2.1  28.2   255   27   14   9.1   5.0   16.5  61.7    -2.5    521  2.6
 11000   -0.7  30.7   255   26   13   9.1   5.0   16.4  61.5    -2.6    466  2.4
 10500    0.7  33.3   250   25   13   9.1   5.0   16.3  61.3    -2.7    410  2.1
 10250    1.3  34.3   245   24   13   9.1   5.0   16.2  61.2    -2.8    382  1.9
 10000    2.0  35.6   245   24   12   9.0   5.0   16.2  61.2    -2.8    355  1.8
  9750    2.7  36.9   245   24   12   8.9   4.9   16.1  61.1    -2.9    327  1.7
  9500    3.3  37.9   245   23   12   9.0   4.9   16.1  61.0    -3.0    300  1.5
  9250    4.0  39.2   240   23   12   9.0   4.9   16.0  60.9    -3.0    272  1.4
  9000    4.7  40.5   240   23   12   9.0   4.9   16.0  60.8    -3.1    245  1.2
  8750    5.3  41.5   240   22   11   9.0   4.9   15.9  60.7    -3.2    218  1.1
  8500    6.0  42.8   240   21   11   9.0   4.9   15.9  60.6    -3.2    190  1.0
  8250    6.7  44.1   240   21   11   9.0   4.9   15.8  60.5    -3.3    163  0.8
  8000    7.3  45.1   240   20   10   9.0   4.9   15.8  60.4    -3.4    136  0.7
  7750    8.0  46.4   240   20   10   9.0   4.9   15.7  60.3    -3.4    108  0.5
  7500    8.7  47.7   235   20   10   9.0   4.9   15.7  60.2    -3.5     81  0.4
  7250    9.3  48.7   235   20   10   9.0   4.9   15.6  60.1    -3.6     53  0.3
  7000   10.0  50.0   230   20   10   9.0   4.9   15.6  60.0    -3.7     26  0.1
  6750   10.7  51.3   230   20   10   8.9   4.9   15.5  59.9    -3.7      M    M
  6500   11.3  52.3   230   19   10   9.2   5.1   15.4  59.7    -3.8      M    M
  6250   12.0  53.6   230   19   10   8.1   4.5   15.4  59.6    -3.9      M    M
  6000   12.7  54.9   230   18    9  12.2   6.7   15.3  59.5    -4.0      M    M
  5750   13.3  55.9   225   14    7  -3.1  -1.7   15.2  59.4    -4.1      M    M
  5500   11.6  52.9   215   10    5 -41.5 -22.8   12.8  55.0    -6.5      M    M

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

           02/22/2017 at 0800 MST          |       02/22/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +5.7        | CAPE...     0.0    LI...       +4.6
CINH...    -0.3    K Index... -15.1        | CINH...     0.0    K Index...  -3.6
                                           |
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 -60.8 -77.4  255  38 19   0.3   0.2 | -59.2 -74.6  260  40 20   0.3   0.2
 45000 -60.3 -76.5  260  43 22   0.5   0.3 | -58.7 -73.7  255  44 23   0.3   0.2
 40000 -58.7 -73.7  260  38 20   1.1   0.6 | -57.7 -71.9  260  41 21   0.6   0.3
 38000 -57.4 -71.3  260  36 19   3.4   1.9 | -56.9 -70.4  260  39 20   2.5   1.4
 36000 -55.4 -67.7  260  34 17   3.4   1.8 | -55.5 -67.9  260  36 18   2.5   1.4
 34000 -53.2 -63.8  260  32 16   6.4   3.5 | -53.4 -64.1  260  33 17   7.0   3.9
 32000 -48.7 -55.7  260  33 17   6.6   3.6 | -49.4 -56.9  255  32 17   6.7   3.7
 30000 -44.5 -48.1  265  33 17   8.0   4.4 | -45.3 -49.5  255  31 16   8.0   4.4
 29000 -42.1 -43.8  260  33 17   8.0   4.4 | -42.9 -45.2  255  31 16   8.0   4.4
 28000 -39.7 -39.5  260  33 17   8.0   4.4 | -40.5 -40.9  255  31 16   8.0   4.4
 27000 -37.3 -35.1  260  33 17   8.1   4.4 | -38.1 -36.6  255  30 16   8.0   4.4
 26000 -34.9 -30.8  260  33 17   8.1   4.5 | -35.6 -32.1  260  31 16   8.1   4.5
 25000 -32.4 -26.3  265  33 17   8.1   4.5 | -33.2 -27.8  260  32 16   8.1   4.5
 24000 -30.0 -22.0  265  32 17   8.1   4.5 | -30.8 -23.4  260  33 17   8.1   4.5
 23000 -27.5 -17.5  265  32 17   8.3   4.5 | -28.4 -19.1  260  33 17   7.9   4.4
 22000 -25.1 -13.2  265  32 17   8.3   4.5 | -26.0 -14.8  260  33 17   7.9   4.4
 21000 -22.6  -8.7  265  32 17   8.1   4.5 | -23.6 -10.5  260  32 17   7.8   4.3
 20000 -20.2  -4.4  265  32 16   8.0   4.4 | -21.3  -6.3  260  31 16   7.6   4.2
 19500 -19.0  -2.2  265  31 16   8.0   4.4 | -20.2  -4.4  260  31 16   7.6   4.2
 19000 -17.8  -0.0  270  31 16   8.0   4.4 | -19.1  -2.4  260  30 15   7.6   4.2
 18500 -16.6   2.1  270  31 16   7.9   4.3 | -17.9  -0.2  260  29 15   7.6   4.2
 18000 -15.4   4.3  270  31 16   7.5   4.1 | -16.2   2.8  260  28 15   7.5   4.1
 17500 -13.8   7.2  270  31 16   7.5   4.1 | -15.1   4.8  260  28 14   7.5   4.1
 17000 -12.7   9.1  265  30 15   7.4   4.1 | -14.0   6.8  260  27 14   7.3   4.0
 16500 -11.5  11.3  265  29 15   7.4   4.1 | -12.9   8.8  260  28 14   7.4   4.0
 16000 -10.4  13.3  265  28 15   7.2   3.9 | -11.9  10.6  260  27 14   6.6   3.6
 15500  -9.4  15.1  265  28 14   7.2   4.0 | -10.9  12.4  260  27 14   6.6   3.6
 15000  -8.3  17.1  265  27 14   7.1   3.9 |  -9.9  14.2  260  27 14   6.3   3.4
 14500  -7.2  19.0  265  27 14   7.1   3.9 |  -9.0  15.8  260  26 13   6.1   3.4
 14000  -6.2  20.8  265  26 14   6.9   3.8 |  -8.1  17.4  265  26 13   6.0   3.3
 13500  -5.2  22.6  265  26 13   6.7   3.6 |  -7.3  18.9  265  24 12   5.7   3.1
 13000  -4.2  24.4  265  26 13   6.4   3.5 |  -6.5  20.3  265  23 12   5.8   3.2
 12500  -3.3  26.1  265  26 13   6.0   3.3 |  -5.6  21.9  265  21 11   6.2   3.4
 12000  -2.4  27.7  270  26 13   5.8   3.2 |  -4.7  23.5  265  19 10   6.3   3.5
 11500  -1.7  28.9  270  26 13   5.1   2.8 |  -3.7  25.3  265  18  9   6.9   3.8
 11000  -0.9  30.4  270  26 13   5.0   2.7 |  -2.7  27.1  265  16  8   6.9   3.8
 10500  -0.2  31.6  270  25 13   4.5   2.5 |  -1.7  28.9  265  14  7   6.9   3.8
 10250   0.1  32.2  270  25 13   4.4   2.4 |  -1.2  29.8  265  13  7   7.7   4.2
 10000   0.4  32.7  270  24 13   4.6   2.5 |  -0.5  31.1  265  12  6   9.7   5.3
  9750   0.7  33.3  270  24 12   5.2   2.8 |   0.2  32.4  265  12  6   9.8   5.4
  9500   1.1  34.0  270  23 12   5.5   3.0 |   0.9  33.6  265  11  6   9.3   5.1
  9250   1.5  34.7  265  22 11   5.0   2.8 |   1.6  34.9  265  11  6   9.1   5.0
  9000   1.8  35.2  265  21 11   6.7   3.7 |   2.3  36.1  265  10  5  10.3   5.6
  8750   2.4  36.3  265  20 10   7.9   4.3 |   3.1  37.6  265   9  5  10.2   5.6
  8500   2.9  37.2  265  19 10   7.1   3.9 |   3.8  38.8  265   9  5   8.9   4.9
  8250   3.5  38.3  265  18  9   7.4   4.0 |   4.5  40.1  270   9  5   9.3   5.1
  8000   4.0  39.2  265  17  9   7.6   4.2 |   5.2  41.4  270   9  4   9.6   5.3
  7750   4.6  40.3  265  16  8   8.2   4.5 |   5.9  42.6  270   8  4  10.0   5.5
  7500   5.2  41.4  265  15  8   8.6   4.7 |   6.7  44.1  270   8  4  10.2   5.6
  7250   5.8  42.4  265  14  7   8.1   4.4 |   7.4  45.3  270   8  4   9.9   5.4
  7000   6.4  43.5  265  13  7   7.5   4.1 |   8.2  46.8  270   8  4   9.5   5.2
  6750   7.0  44.6  265  12  6   7.4   4.1 |   8.9  48.0  270   7  4   9.9   5.4
  6500   7.5  45.5  260  10  5   7.2   4.0 |   9.6  49.3  270   7  4  10.3   5.7
  6250   8.0  46.4  260   9  5   5.7   3.1 |  10.4  50.7  275   7  4  10.5   5.8
  6000   8.4  47.1  255   7  4   5.0   2.7 |  11.2  52.2  275   7  3  11.4   6.2
  5750   8.7  47.7  255   6  3   4.2   2.3 |  12.0  53.6  275   6  3   9.4   5.1
  5500   8.9  48.0  255   4  2  -1.0  -0.5 |  12.8  55.0  275   6  3  12.4   6.8

           02/22/2017 at 1400 MST          |       02/22/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +2.9        | CAPE...     0.0    LI...       +2.4
CINH...    -0.0    K Index...  +6.2        | CINH...    -0.1    K Index... +13.5
                                           |
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  260  39 20   0.2   0.1 | -57.7 -71.9  265  35 18   0.6   0.3
 45000 -58.1 -72.6  260  44 23   0.2   0.1 | -56.8 -70.2  265  44 23   0.7   0.4
 40000 -58.0 -72.4  260  42 22   0.1   0.0 | -57.1 -70.8  260  41 21  -0.3  -0.1
 38000 -57.2 -71.0  255  40 21   3.2   1.7 | -56.7 -70.1  260  40 20   2.7   1.5
 36000 -55.4 -67.7  255  37 19   3.2   1.7 | -55.1 -67.2  255  38 19   2.7   1.5
 34000 -52.9 -63.2  255  35 18   7.0   3.9 | -53.0 -63.4  255  35 18   6.5   3.6
 32000 -48.9 -56.0  255  34 17   6.6   3.6 | -49.1 -56.4  255  35 18   6.5   3.6
 30000 -44.9 -48.8  255  33 17   7.9   4.3 | -45.1 -49.2  255  34 17   7.3   4.0
 29000 -42.5 -44.5  255  33 17   7.8   4.3 | -43.0 -45.4  255  34 17   7.2   4.0
 28000 -40.2 -40.4  255  33 17   7.8   4.3 | -40.8 -41.4  255  34 17   7.2   4.0
 27000 -37.9 -36.2  255  33 17   7.8   4.3 | -38.7 -37.7  255  34 17   7.1   3.9
 26000 -35.5 -31.9  255  32 17   7.9   4.4 | -36.3 -33.3  255  32 17   8.1   4.4
 25000 -33.1 -27.6  255  32 16   7.9   4.4 | -33.9 -29.0  255  31 16   8.1   4.4
 24000 -30.7 -23.3  255  31 16   8.0   4.4 | -31.5 -24.7  255  29 15   8.1   4.4
 23000 -28.5 -19.3  255  31 16   7.4   4.1 | -29.1 -20.4  255  29 15   7.8   4.3
 22000 -26.2 -15.2  260  32 16   7.4   4.1 | -26.8 -16.2  255  28 15   7.8   4.3
 21000 -24.0 -11.2  260  32 17   7.4   4.0 | -24.4 -11.9  255  28 14   7.8   4.3
 20000 -21.9  -7.4  260  31 16   7.1   3.9 | -22.3  -8.1  255  27 14   7.1   3.9
 19500 -20.8  -5.4  260  31 16   7.1   3.9 | -21.2  -6.2  255  27 14   7.1   3.9
 19000 -19.8  -3.6  260  30 16   7.1   3.9 | -20.2  -4.4  260  27 14   7.1   3.9
 18500 -18.7  -1.7  260  30 15   7.1   3.9 | -19.1  -2.4  260  27 14   7.2   4.0
 18000 -17.2   1.0  260  28 15   6.8   3.7 | -17.6   0.3  260  26 13   6.3   3.4
 17500 -16.2   2.8  260  27 14   6.8   3.7 | -16.7   1.9  260  25 13   6.3   3.5
 17000 -15.2   4.6  260  26 14   6.7   3.7 | -15.8   3.6  255  24 12   6.0   3.3
 16500 -14.2   6.4  260  25 13   6.8   3.7 | -14.9   5.2  255  22 11   6.1   3.3
 16000 -13.2   8.2  260  24 12   6.2   3.4 | -14.0   6.8  255  21 11   6.4   3.5
 15500 -12.3   9.9  255  22 11   6.2   3.4 | -13.1   8.4  255  19 10   6.5   3.6
 15000 -11.4  11.5  255  20 10   6.3   3.5 | -12.1  10.2  255  18  9   7.0   3.8
 14500 -10.5  13.1  255  18  9   6.5   3.6 | -11.0  12.2  255  16  8   7.7   4.2
 14000  -9.5  14.9  255  16  8   6.7   3.7 |  -9.9  14.2  250  14  7   7.9   4.3
 13500  -8.5  16.7  250  14  7   7.3   4.0 |  -8.7  16.3  250  13  7   8.7   4.7
 13000  -7.4  18.7  250  12  6   7.6   4.2 |  -7.4  18.7  250  12  6   8.6   4.7
 12500  -6.2  20.8  250  11  6   8.7   4.8 |  -6.1  21.0  245  11  5   9.1   5.0
 12000  -4.9  23.2  245   9  5   8.8   4.8 |  -4.7  23.5  245  10  5   9.1   5.0
 11500  -3.5  25.7  245   9  4   9.8   5.4 |  -3.3  26.1  240   9  5   9.4   5.1
 11000  -2.0  28.4  245   8  4   9.7   5.3 |  -1.9  28.6  240   8  4   9.3   5.1
 10500  -0.6  30.9  245   8  4   8.9   4.9 |  -0.6  30.9  235   7  4   8.3   4.6
 10250   0.0  32.0  245   7  4   9.6   5.3 |   0.0  32.0  235   7  3   9.1   5.0
 10000   0.8  33.4  245   7  4  10.9   6.0 |   0.8  33.4  235   7  3  10.6   5.8
  9750   1.6  34.9  245   7  4  10.7   5.8 |   1.6  34.9  235   7  3  10.7   5.9
  9500   2.4  36.3  245   7  4  10.1   5.5 |   2.3  36.1  230   6  3  10.1   5.5
  9250   3.2  37.8  245   7  3  10.7   5.9 |   3.1  37.6  230   6  3  10.8   5.9
  9000   3.9  39.0  245   7  3   8.8   4.8 |   3.9  39.0  230   6  3   8.6   4.7
  8750   4.5  40.1  250   7  3   8.5   4.7 |   4.4  39.9  230   6  3   8.2   4.5
  8500   5.3  41.5  250   7  3  10.2   5.6 |   5.2  41.4  230   6  3  10.0   5.5
  8250   6.0  42.8  250   6  3   9.8   5.4 |   5.9  42.6  230   6  3   9.5   5.2
  8000   6.7  44.1  250   6  3   9.7   5.3 |   6.6  43.9  230   5  3   9.8   5.4
  7750   7.5  45.5  250   6  3   9.8   5.4 |   7.4  45.3  225   5  3   9.7   5.3
  7500   8.2  46.8  250   6  3  10.1   5.5 |   8.1  46.6  225   5  3   9.6   5.3
  7250   9.0  48.2  250   6  3   9.9   5.4 |   8.8  47.8  230   5  3   9.6   5.3
  7000   9.7  49.5  250   6  3   9.6   5.2 |   9.5  49.1  225   5  3   9.2   5.1
  6750  10.4  50.7  250   6  3  10.1   5.5 |  10.2  50.4  225   5  3   9.7   5.3
  6500  11.2  52.2  250   6  3  10.6   5.8 |  11.0  51.8  225   5  2  10.2   5.6
  6250  12.0  53.6  250   6  3  10.5   5.7 |  11.7  53.1  225   4  2  10.1   5.6
  6000  12.8  55.0  250   5  3  11.1   6.1 |  12.5  54.5  225   4  2  10.6   5.8
  5750  13.6  56.5  250   5  3   9.2   5.0 |  13.3  55.9  220   4  2   9.6   5.2
  5500  14.3  57.7  250   5  3  12.7   7.0 |  13.9  57.0  225   4  2   7.8   4.3
________________________________________________________________________________

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.

CINH (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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