Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 140050
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1750 MST Tuesday, February 13, 2018

This forecast is for Wednesday, February 14, 2018:

If the trigger temperature of 54.4 F/12.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 409 ft/min (2.1 m/s)
   Maximum height of thermals.................. 11422 ft MSL (6087 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 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................. 9895 ft MSL (4560 ft AGL)
Thermal soaring outlook for Thursday 02/15..... Poor

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... Improving through the day.
Height of stable layer (12-18K ft MSL)......... 9500 ft MSL (4165 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 53139 ft MSL (47804 ft AGL)
Wave soaring outlook for Thursday 02/15........ Good

Remarks... Strong westerly flow across northern colorado Wednesday with a
           mountain wave and gusty winds near the foothills.

Sunrise/Sunset.................... 06:52:51 / 17:34:26 MST
Total possible sunshine........... 10 hr 41 min 34 sec (641 min 34 sec)
Altitude of sun at 12:13:39 MST... 37.30 degrees

Upper air data from numerical model forecast valid on 02/14/2018 at 0500 MST

Freezing level.................. 5345 ft MSL (10 ft AGL)
Additional freezing level....... 9760 ft MSL (4425 ft AGL)
Convective condensation level... 17914 ft MSL (12579 ft AGL)
Lifted condensation level....... 15156 ft MSL (9821 ft AGL)
Lifted index.................... +5.8
K index......................... -13.4

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  -64.7 -84.5   250   40   21   1.0   0.6      M     M       M      M    M
 45000  -63.2 -81.8   250   41   21   1.5   0.8      M     M       M      M    M
 40000  -60.3 -76.5   250   43   22   1.9   1.1      M     M       M      M    M
 38000  -57.9 -72.2   250   43   22   5.6   3.1      M     M       M      M    M
 36000  -54.1 -65.4   250   43   22   5.6   3.1      M     M       M      M    M
 34000  -50.3 -58.5   250   43   22   7.6   4.2      M     M       M      M    M
 32000  -45.8 -50.4   250   41   21   7.6   4.2      M     M       M      M    M
 30000  -41.1 -42.0   250   39   20   8.0   4.4   35.1  95.2    13.8      M    M
 29000  -38.7 -37.7   250   39   20   8.0   4.4   34.3  93.8    13.4      M    M
 28000  -36.3 -33.3   250   38   20   8.0   4.4   33.7  92.6    13.1      M    M
 27000  -34.0 -29.2   250   38   20   7.3   4.0   33.1  91.6    12.8      M    M
 26000  -31.8 -25.2   250   37   19   7.1   3.9   31.9  89.5    12.0      M    M
 25000  -29.7 -21.5   250   35   18   7.1   3.9   30.9  87.7    11.4      M    M
 24000  -27.6 -17.7   250   34   17   7.2   3.9   30.1  86.1    10.8      M    M
 23000  -25.4 -13.7   250   33   17   7.4   4.0   29.1  84.3    10.1      M    M
 22000  -23.2  -9.8   255   32   17   7.4   4.0   28.2  82.8     9.5      M    M
 21000  -21.0  -5.8   255   31   16   7.4   4.1   27.4  81.4     9.0      M    M
 20000  -18.7  -1.7   255   30   15   7.5   4.1   26.6  79.8     8.3      M    M
 19500  -17.0   1.4   255   29   15   7.5   4.1   26.0  78.7     7.9      M    M
 19000  -15.9   3.4   255   28   14   7.6   4.2   25.6  78.1     7.7      M    M
 18500  -14.8   5.4   255   27   14   6.4   3.5   25.2  77.3     7.3      M    M
 18000  -13.9   7.0   255   26   13   6.4   3.5   24.6  76.3     6.9      M    M
 17500  -12.9   8.8   255   24   12   6.3   3.5   24.0  75.3     6.4      M    M
 17000  -12.0  10.4   250   23   12   6.2   3.4   23.4  74.1     5.9      M    M
 16500  -11.0  12.2   250   21   11   6.2   3.4   22.8  73.1     5.4      M    M
 16000  -10.1  13.8   250   20   10   6.5   3.6   22.2  72.0     4.9      M    M
 15500   -9.1  15.6   250   19   10   6.5   3.6   21.7  71.0     4.5      M    M
 15000   -8.2  17.2   250   18    9   6.1   3.3   21.1  70.0     4.0      M    M
 14500   -7.3  18.9   250   17    9   6.0   3.3   20.5  68.9     3.4      M    M
 14000   -6.4  20.5   255   17    9   6.8   3.7   19.9  67.8     2.9      M    M
 13500   -5.3  22.5   260   18    9   7.1   3.9   19.5  67.0     2.5      M    M
 13000   -4.2  24.4   260   18    9   6.7   3.7   19.1  66.3     2.1      M    M
 12500   -3.3  26.1   260   19   10   6.1   3.4   18.5  65.3     1.6      M    M
 12000   -2.4  27.7   260   20   10   5.4   3.0   17.9  64.2     1.0      M    M
 11500   -1.8  28.8   265   21   11   4.1   2.2   17.0  62.6     0.1      M    M
 11000   -1.3  29.7   265   21   11   3.8   2.1   16.1  61.0    -0.8    382  1.9
 10500   -0.8  30.6   265   21   11   3.3   1.8   15.1  59.2    -1.8    354  1.8
 10250   -0.6  30.9   265   21   11   3.1   1.7   14.6  58.2    -2.3    340  1.7
 10000   -0.4  31.3   265   21   11   4.3   2.4   14.1  57.4    -2.8    325  1.7
  9750   -0.0  32.0   265   20   10   4.6   2.5   13.7  56.6    -3.2    308  1.6
  9500    0.3  32.5   265   19   10   3.8   2.1   13.2  55.8    -3.7    292  1.5
  9250    0.5  32.9   265   18    9   3.7   2.0   12.8  55.0    -4.1    276  1.4
  9000    0.8  33.4   265   17    9   3.0   1.6   12.3  54.1    -4.6    262  1.3
  8750    1.0  33.8   265   16    8   5.0   2.7   11.8  53.2    -5.1    247  1.3
  8500    1.5  34.7   260   14    7   6.6   3.6   11.5  52.7    -5.4    226  1.1
  8250    2.0  35.6   260   13    6   6.2   3.4   11.3  52.3    -5.7    204  1.0
  8000    2.4  36.3   260   11    6   6.3   3.5   11.0  51.8    -6.0    183  0.9
  7750    2.9  37.2   260    9    5   6.6   3.6   10.7  51.3    -6.3    162  0.8
  7500    3.4  38.1   255    8    4   6.7   3.7   10.5  50.9    -6.5    139  0.7
  7250    3.9  39.0   255    6    3   6.9   3.8   10.3  50.5    -6.7    116  0.6
  7000    4.5  40.1   245    5    3   7.6   4.2   10.1  50.1    -6.9     92  0.5
  6750    5.0  41.0   235    4    2   6.2   3.4    9.9  49.8    -7.1     69  0.3
  6500    5.3  41.5   220    3    2   2.1   1.1    9.5  49.0    -7.6     52  0.3
  6250    5.3  41.5   205    3    2  -2.0  -1.1    8.7  47.7    -8.3     44  0.2
  6000    5.1  41.2   190    4    2  -3.7  -2.0    7.7  45.9    -9.3     44  0.2
  5750    4.9  40.8   180    4    2  -1.8  -1.0    6.8  44.2   -10.3     43  0.2
  5500    4.3  39.7   180    5    2 -18.6 -10.2    5.5  42.0   -11.6     52  0.3

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

           02/14/2018 at 0800 MST          |       02/14/2018 at 1100 MST
                                           |
CAPE...     0.0    LI...       +6.2        | CAPE...     0.0    LI...       +5.9
CINH...    -0.1    K Index...  -4.2        | CINH...    -0.1    K Index...  -3.5
                                           |
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 -66.5 -87.7  250  44 23   0.9   0.5 | -67.5 -89.5  250  46 24   1.6   0.9
 45000 -65.1 -85.2  250  43 22   2.0   1.1 | -64.9 -84.8  245  44 23   2.2   1.2
 40000 -61.3 -78.3  250  47 24   2.5   1.4 | -61.3 -78.3  250  52 27   2.3   1.3
 38000 -58.3 -72.9  250  48 25   6.7   3.7 | -58.3 -72.9  250  54 28   6.7   3.7
 36000 -54.3 -65.7  250  50 26   6.7   3.7 | -54.3 -65.7  245  56 29   6.7   3.7
 34000 -50.2 -58.4  250  50 26   7.7   4.2 | -50.0 -58.0  245  57 29   8.2   4.5
 32000 -45.0 -49.0  250  46 24   7.7   4.2 | -44.4 -47.9  245  53 27   8.3   4.5
 30000 -40.4 -40.7  250  42 22   7.6   4.1 | -39.7 -39.5  245  49 25   7.3   4.0
 29000 -38.1 -36.6  245  40 21   7.5   4.1 | -37.5 -35.5  245  46 24   7.3   4.0
 28000 -35.9 -32.6  245  38 20   7.5   4.1 | -35.3 -31.5  240  43 22   7.3   4.0
 27000 -33.6 -28.5  245  37 19   7.2   4.0 | -33.2 -27.8  240  40 21   7.1   3.9
 26000 -31.5 -24.7  245  35 18   7.2   3.9 | -31.0 -23.8  240  38 19   7.1   3.9
 25000 -29.3 -20.7  245  33 17   7.2   3.9 | -28.9 -20.0  240  36 18   7.1   3.9
 24000 -27.2 -17.0  245  32 16   7.0   3.9 | -26.8 -16.2  240  33 17   7.1   3.9
 23000 -25.2 -13.4  245  30 16   6.8   3.7 | -24.7 -12.5  240  31 16   7.1   3.9
 22000 -23.1  -9.6  245  29 15   6.8   3.7 | -22.6  -8.7  240  30 15   7.1   3.9
 21000 -21.1  -6.0  250  28 14   7.4   4.0 | -20.5  -4.9  245  28 14   6.9   3.8
 20000 -18.8  -1.8  250  27 14   7.5   4.1 | -18.4  -1.1  245  27 14   6.8   3.7
 19500 -17.7   0.1  250  27 14   7.5   4.1 | -17.4   0.7  245  27 14   6.8   3.7
 19000 -16.6   2.1  250  26 14   7.5   4.1 | -16.4   2.5  245  26 13   6.8   3.7
 18500 -15.5   4.1  250  26 13   7.5   4.1 | -15.4   4.3  245  26 13   6.9   3.8
 18000 -13.8   7.2  250  26 13   7.6   4.1 | -13.8   7.2  250  25 13   7.1   3.9
 17500 -12.6   9.3  250  26 13   7.5   4.1 | -12.7   9.1  250  25 13   7.1   3.9
 17000 -11.5  11.3  255  26 13   7.4   4.1 | -11.6  11.1  250  25 13   7.2   4.0
 16500 -10.4  13.3  255  26 13   7.3   4.0 | -10.6  12.9  250  25 13   7.2   4.0
 16000  -9.4  15.1  255  25 13   6.9   3.8 |  -9.5  14.9  250  25 13   7.3   4.0
 15500  -8.3  17.1  255  25 13   7.0   3.8 |  -8.4  16.9  255  25 13   7.3   4.0
 15000  -7.3  18.9  255  25 13   6.5   3.6 |  -7.3  18.9  255  26 13   6.8   3.7
 14500  -6.3  20.7  255  25 13   6.5   3.6 |  -6.3  20.7  255  25 13   6.8   3.7
 14000  -5.4  22.3  255  26 13   6.2   3.4 |  -5.3  22.5  255  25 13   6.4   3.5
 13500  -4.5  23.9  260  26 13   6.0   3.3 |  -4.4  24.1  255  25 13   6.1   3.4
 13000  -3.6  25.5  260  26 13   5.9   3.2 |  -3.5  25.7  255  24 13   5.7   3.1
 12500  -2.8  27.0  260  26 13   5.7   3.1 |  -2.7  27.1  255  25 13   5.3   2.9
 12000  -1.9  28.6  260  26 14   5.3   2.9 |  -1.9  28.6  260  25 13   5.0   2.8
 11500  -1.2  29.8  260  25 13   4.8   2.6 |  -1.3  29.7  260  25 13   4.6   2.5
 11000  -0.6  30.9  260  24 13   4.7   2.6 |  -0.6  30.9  260  25 13   4.8   2.6
 10500   0.1  32.2  260  24 12   4.6   2.5 |   0.1  32.2  260  24 12   5.0   2.8
 10250   0.4  32.7  260  23 12   5.0   2.7 |   0.5  32.9  260  23 12   5.8   3.2
 10000   0.8  33.4  265  24 12   4.6   2.5 |   1.0  33.8  260  23 12   6.4   3.5
  9750   1.1  34.0  265  23 12   4.0   2.2 |   1.4  34.5  260  22 11   5.9   3.2
  9500   1.4  34.5  265  23 12   4.2   2.3 |   1.8  35.2  260  21 11   5.9   3.2
  9250   1.7  35.1  265  22 11   4.0   2.2 |   2.3  36.1  260  20 10   5.8   3.2
  9000   2.0  35.6  265  21 11   4.2   2.3 |   2.7  36.9  260  18  9   6.9   3.8
  8750   2.3  36.1  265  20 10   5.1   2.8 |   3.3  37.9  260  17  9   7.8   4.3
  8500   2.7  36.9  265  18 10   5.3   2.9 |   3.8  38.8  260  16  8   7.5   4.1
  8250   3.1  37.6  265  17  9   5.6   3.1 |   4.4  39.9  260  15  8   7.8   4.3
  8000   3.5  38.3  265  15  8   6.3   3.4 |   5.0  41.0  260  13  7   8.3   4.5
  7750   4.0  39.2  265  13  7   6.6   3.6 |   5.6  42.1  260  12  6   8.0   4.4
  7500   4.5  40.1  265  12  6   6.7   3.7 |   6.2  43.2  260  11  6   7.8   4.3
  7250   5.0  41.0  265  11  5   6.6   3.6 |   6.7  44.1  260  10  5   7.6   4.1
  7000   5.4  41.7  265   9  4   6.5   3.5 |   7.3  45.1  255   9  4   7.3   4.0
  6750   5.9  42.6  260   7  3   6.3   3.5 |   7.8  46.0  255   7  4   7.0   3.8
  6500   6.3  43.3  255   6  3   4.1   2.2 |   8.3  46.9  250   6  3   6.2   3.4
  6250   6.5  43.7  250   4  2   0.4   0.2 |   8.7  47.7  245   5  2   5.1   2.8
  6000   6.5  43.7  230   3  2  -0.1  -0.1 |   9.0  48.2  235   3  2   4.3   2.4
  5750   6.5  43.7  200   3  2  -1.4  -0.8 |   9.4  48.9  210   2  1   5.2   2.9
  5500   5.8  42.4  190   3  2 -21.7 -11.9 |   9.7  49.5  190   2  1   4.7   2.6

           02/14/2018 at 1400 MST          |       02/14/2018 at 1700 MST
                                           |
CAPE...     0.0    LI...       +6.0        | CAPE...     0.0    LI...       +6.2
CINH...    -0.1    K Index...  -3.3        | CINH...    -0.0    K Index...  -6.1
                                           |
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 -66.0 -86.8  245  45 23   2.9   1.6 | -65.8 -86.4  245  45 23   3.1   1.7
 45000 -61.6 -78.9  240  46 24   1.5   0.8 | -61.2 -78.2  245  47 24   1.5   0.8
 40000 -60.9 -77.6  245  57 29   0.5   0.3 | -61.0 -77.8  245  59 30   0.1   0.1
 38000 -58.5 -73.3  245  60 31   6.7   3.7 | -58.6 -73.5  245  62 32   7.4   4.1
 36000 -54.0 -65.2  245  63 32   6.7   3.7 | -54.1 -65.4  240  66 34   7.4   4.1
 34000 -49.7 -57.5  245  64 33   8.6   4.7 | -49.0 -56.2  240  67 34   8.0   4.4
 32000 -44.5 -48.1  245  62 32   8.6   4.7 | -44.2 -47.6  240  63 32   8.0   4.4
 30000 -39.6 -39.3  245  59 30   7.3   4.0 | -39.5 -39.1  240  59 30   7.6   4.2
 29000 -37.4 -35.3  245  56 29   7.2   4.0 | -37.2 -35.0  240  58 30   7.6   4.2
 28000 -35.2 -31.4  240  54 28   7.2   4.0 | -35.0 -31.0  240  56 29   7.6   4.2
 27000 -33.1 -27.6  240  51 26   6.6   3.6 | -32.7 -26.9  240  55 28   6.8   3.7
 26000 -31.2 -24.2  240  47 24   6.2   3.4 | -30.9 -23.6  240  52 27   6.1   3.3
 25000 -29.4 -20.9  240  43 22   6.2   3.4 | -29.1 -20.4  240  49 25   6.1   3.3
 24000 -27.5 -17.5  240  39 20   6.5   3.5 | -27.2 -17.0  240  45 23   6.2   3.4
 23000 -25.3 -13.5  240  35 18   7.5   4.1 | -25.2 -13.4  240  41 21   7.0   3.9
 22000 -23.1  -9.6  245  31 16   7.5   4.1 | -23.1  -9.6  240  37 19   7.0   3.9
 21000 -20.8  -5.4  245  27 14   7.3   4.0 | -21.0  -5.8  245  32 17   6.9   3.8
 20000 -18.7  -1.7  245  27 14   7.2   4.0 | -18.9  -2.0  245  30 15   6.8   3.7
 19500 -17.0   1.4  250  26 14   7.2   4.0 | -17.9  -0.2  245  28 15   6.8   3.7
 19000 -16.0   3.2  250  26 14   7.3   4.0 | -16.4   2.5  245  27 14   6.8   3.7
 18500 -14.9   5.2  250  26 13   6.6   3.6 | -15.4   4.3  245  26 13   6.3   3.5
 18000 -14.0   6.8  250  26 13   6.5   3.6 | -14.5   5.9  250  25 13   6.2   3.4
 17500 -13.0   8.6  250  26 13   6.5   3.6 | -13.5   7.7  250  24 12   6.4   3.5
 17000 -12.0  10.4  255  25 13   6.7   3.7 | -12.5   9.5  250  23 12   7.1   3.9
 16500 -11.0  12.2  255  25 13   6.7   3.7 | -11.5  11.3  250  21 11   7.1   3.9
 16000 -10.0  14.0  255  25 13   6.6   3.6 | -10.4  13.3  250  20 10   6.5   3.6
 15500  -9.0  15.8  255  25 13   6.6   3.6 |  -9.5  14.9  250  20 10   6.5   3.6
 15000  -8.0  17.6  255  25 13   6.2   3.4 |  -8.5  16.7  250  20 10   6.7   3.7
 14500  -7.1  19.2  255  25 13   6.1   3.3 |  -7.5  18.5  255  21 11   6.8   3.7
 14000  -6.2  20.8  255  26 13   6.0   3.3 |  -6.4  20.5  255  21 11   6.5   3.6
 13500  -5.3  22.5  255  25 13   5.8   3.2 |  -5.6  21.9  255  22 11   5.9   3.2
 13000  -4.5  23.9  255  24 12   5.9   3.2 |  -4.7  23.5  255  22 11   5.8   3.2
 12500  -3.6  25.5  255  24 12   6.2   3.4 |  -3.9  25.0  255  22 11   5.3   2.9
 12000  -2.7  27.1  255  24 12   6.4   3.5 |  -3.1  26.4  255  22 11   5.4   2.9
 11500  -1.6  29.1  255  22 11   7.2   3.9 |  -2.3  27.9  255  21 11   5.9   3.2
 11000  -0.6  30.9  255  20 10   6.8   3.7 |  -1.4  29.5  255  19 10   5.9   3.2
 10500   0.3  32.5  255  19 10   4.8   2.6 |  -0.6  30.9  255  17  9   6.0   3.3
 10250   0.6  33.1  255  19 10   6.2   3.4 |  -0.1  31.8  255  17  9   6.7   3.7
 10000   1.2  34.2  255  18  9   9.0   4.9 |   0.4  32.7  255  16  8   8.9   4.9
  9750   1.9  35.4  255  17  9   8.9   4.9 |   1.1  34.0  255  15  8   9.2   5.1
  9500   2.5  36.5  255  16  8   8.2   4.5 |   1.8  35.2  255  14  7   8.7   4.8
  9250   3.1  37.6  255  15  8   8.0   4.4 |   2.4  36.3  255  14  7   8.5   4.7
  9000   3.7  38.7  255  14  7   9.5   5.2 |   3.1  37.6  255  13  7   9.8   5.4
  8750   4.5  40.1  250  14  7  10.1   5.5 |   3.8  38.8  250  13  7  10.0   5.5
  8500   5.2  41.4  250  13  7   8.8   4.8 |   4.5  40.1  250  13  6   8.9   4.9
  8250   5.8  42.4  250  12  6   9.2   5.1 |   5.2  41.4  250  12  6   9.1   5.0
  8000   6.5  43.7  250  12  6   9.9   5.4 |   5.9  42.6  250  12  6  10.0   5.5
  7750   7.3  45.1  250  11  6   9.2   5.1 |   6.7  44.1  250  11  6   9.6   5.3
  7500   7.9  46.2  250  10  5   8.1   4.5 |   7.3  45.1  250  10  5   8.3   4.6
  7250   8.5  47.3  250   9  5   8.8   4.8 |   8.0  46.4  250  10  5   9.1   5.0
  7000   9.2  48.6  250   8  4   9.7   5.3 |   8.7  47.7  250   9  5  10.5   5.8
  6750   9.9  49.8  250   7  4   8.5   4.6 |   9.4  48.9  250   9  4   9.0   4.9
  6500  10.4  50.7  250   6  3   7.2   4.0 |  10.0  50.0  245   8  4   7.5   4.1
  6250  11.0  51.8  250   5  3   7.9   4.3 |  10.6  51.1  245   7  4   7.4   4.1
  6000  11.6  52.9  250   5  2   8.1   4.5 |  11.1  52.0  245   6  3   6.5   3.6
  5750  12.1  53.8  250   4  2   8.2   4.5 |  11.6  52.9  240   5  2   7.2   4.0
  5500  12.7  54.9  250   3  1   8.9   4.9 |  11.9  53.4  235   3  2  -0.7  -0.4
________________________________________________________________________________

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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