Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 250022
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1822 MDT Friday, April 24, 2015

This forecast is for Saturday, April 25, 2015:

If the trigger temperature of 61.9 F/16.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 729 ft/min (3.7 m/s)
   Maximum height of thermals.................. 15414 ft MSL (10107 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8677 ft MSL (3370 ft AGL)
Thermal soaring outlook for Sunday 04/26....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 14893 ft MSL (9586 ft AGL)
Wave soaring outlook for Sunday 04/26.......... Poor

Remarks...

Sunrise/Sunset.................... 06:08:06 / 19:46:35 MDT
Total possible sunshine........... 13 hr 38 min 29 sec (818 min 29 sec)
Altitude of sun at 12:57:31 MDT... 63.50 degrees

Upper air data from numerical model forecast valid on 04/25/2015 at 0600 MDT

Freezing level.................. 10900 ft MSL (5593 ft AGL)
Convective condensation level... 14659 ft MSL (9352 ft AGL)
Lifted condensation level....... 15014 ft MSL (9707 ft AGL)
Lifted index.................... -1.1
K index......................... +12.2

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  -54.8 -66.6   240   40   21   0.2   0.1      M     M       M      M    M
 45000  -54.5 -66.1   245   36   19  -0.0  -0.0      M     M       M      M    M
 40000  -57.5 -71.5   265   41   21  -2.1  -1.1      M     M       M      M    M
 38000  -57.6 -71.7   270   42   22   2.8   1.5      M     M       M      M    M
 36000  -56.0 -68.8   275   39   20   2.8   1.5      M     M       M      M    M
 34000  -54.2 -65.6   280   37   19   5.4   2.9      M     M       M      M    M
 32000  -50.3 -58.5   280   30   15   6.6   3.6      M     M       M      M    M
 30000  -45.7 -50.3   280   21   11   7.2   3.9   29.3  84.7     7.4      M    M
 29000  -43.6 -46.5   275   18    9   7.2   3.9   28.1  82.7     6.6      M    M
 28000  -41.4 -42.5   265   15    8   7.2   3.9   27.2  80.9     5.9      M    M
 27000  -39.3 -38.7   255   13    7   7.5   4.1   26.3  79.3     5.3      M    M
 26000  -36.7 -34.1   250   12    6   8.9   4.9   25.8  78.5     5.0      M    M
 25000  -34.0 -29.2   250   12    6   8.9   4.9   25.5  77.9     4.8      M    M
 24000  -31.3 -24.3   245   11    6   9.0   4.9   25.3  77.5     4.7      M    M
 23000  -28.6 -19.5   250   11    6   8.9   4.9   24.9  76.9     4.5      M    M
 22000  -26.0 -14.8   255   11    6   8.9   4.9   24.6  76.3     4.3      M    M
 21000  -23.3  -9.9   260   11    5   8.5   4.7   24.4  76.0     4.2      M    M
 20000  -20.9  -5.6   255   10    5   7.9   4.3   23.7  74.7     3.6      M    M
 19500  -19.8  -3.6   255   10    5   7.9   4.3   23.4  74.1     3.3      M    M
 19000  -18.6  -1.5   255   10    5   7.9   4.3   23.1  73.5     3.0      M    M
 18500  -17.4   0.7   250    9    5   7.8   4.3   22.8  73.0     2.8      M    M
 18000  -16.4   2.5   250    9    5   6.7   3.7   22.3  72.2     2.4      M    M
 17500  -15.4   4.3   250    9    5   6.8   3.7   21.8  71.3     1.9      M    M
 17000  -14.4   6.1   250    9    5   6.8   3.8   21.3  70.4     1.5      M    M
 16500  -13.4   7.9   255    9    5   6.9   3.8   20.8  69.5     1.1      M    M
 16000  -12.4   9.7   260   10    5   6.9   3.8   20.3  68.6     0.6      M    M
 15500  -10.8  12.6   250    8    4   7.0   3.9   19.6  67.3    -0.0    926  4.7
 15000   -9.8  14.4   245    7    4   7.2   3.9   19.2  66.6    -0.4    880  4.5
 14500   -8.7  16.3   235    6    3   7.3   4.0   18.8  65.8    -0.8    833  4.2
 14000   -7.6  18.3   215    5    3   7.3   4.0   18.4  65.1    -1.2    787  4.0
 13500   -6.5  20.3   200    5    3   7.4   4.1   18.0  64.4    -1.6    739  3.8
 13000   -5.5  22.1   185    5    3   7.7   4.2   17.6  63.7    -2.0    692  3.5
 12500   -4.2  24.4   185    5    2   8.9   4.9   17.4  63.3    -2.2    640  3.3
 12000   -2.9  26.8   190    4    2   8.9   4.9   17.3  63.1    -2.4    586  3.0
 11500   -1.6  29.1   200    3    2   9.4   5.1   17.2  62.9    -2.5    531  2.7
 11000   -0.2  31.6   220    3    1   9.3   5.1   17.1  62.8    -2.6    474  2.4
 10500    1.2  34.2   255    3    2   8.7   4.8   17.0  62.6    -2.7    419  2.1
 10250    1.8  35.2   270    4    2   9.7   5.3   16.9  62.5    -2.8    392  2.0
 10000    2.6  36.7   280    4    2  11.0   6.1   17.0  62.6    -2.7    361  1.8
  9750    3.4  38.1   290    6    3  10.3   5.7   17.1  62.8    -2.7    329  1.7
  9500    4.2  39.6   295    8    4   9.5   5.2   17.1  62.8    -2.7    300  1.5
  9250    4.9  40.8   300   11    6  10.2   5.6   17.1  62.8    -2.7    271  1.4
  9000    5.6  42.1   300   13    7   8.3   4.5   17.1  62.8    -2.7    242  1.2
  8750    6.1  43.0   300   15    8   6.9   3.8   16.9  62.4    -2.9    220  1.1
  8500    6.7  44.1   300   18    9   7.7   4.2   16.7  62.1    -3.1    196  1.0
  8250    7.2  45.0   295   20   10   7.7   4.2   16.5  61.8    -3.3    172  0.9
  8000    7.8  46.0   295   23   12   6.7   3.7   16.4  61.5    -3.5    148  0.8
  7750    8.1  46.6   295   24   12   4.4   2.4   16.0  60.9    -3.9    129  0.7
  7500    8.4  47.1   295   23   12   3.8   2.1   15.6  60.1    -4.3    114  0.6
  7250    8.7  47.7   290   23   12   4.0   2.2   15.1  59.3    -4.8     99  0.5
  7000    8.9  48.0   290   22   11   4.1   2.2   14.7  58.5    -5.3     83  0.4
  6750    9.2  48.6   290   19   10   3.9   2.1   14.3  57.7    -5.7     67  0.3
  6500    9.6  49.3   290   16    8   6.0   3.3   13.9  57.0    -6.2     50  0.3
  6250    9.9  49.8   285   14    7  -1.1  -0.6   13.5  56.3    -6.6     32  0.2
  6000    9.4  48.9   275   11    6  -7.4  -4.0   12.3  54.1    -7.8     40  0.2
  5750    8.6  47.5   265    9    5 -18.2 -10.0   10.8  51.4    -9.3     55  0.3
  5500    6.0  42.8   235    8    4 -48.2 -26.4    7.6  45.6   -12.7    126  0.6

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

           04/25/2015 at 0900 MDT          |       04/25/2015 at 1200 MDT
                                           |
K index... +13.7  LI... +275.5             | K index... +13.9  LI... +272.5
CAPE... 0.0  CIN... -0.8                   | CAPE... +48.6  CIN... -32.5
                                           |
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 -55.2 -67.4  235  38 19  -0.3  -0.2 | -55.3 -67.5  235  36 18  -0.0  -0.0
 45000 -55.7 -68.3  250  40 21  -0.5  -0.3 | -55.3 -67.5  245  42 22  -0.4  -0.2
 40000 -58.2 -72.8  255  47 24  -1.7  -0.9 | -58.5 -73.3  250  54 28  -2.2  -1.2
 38000 -58.2 -72.8  260  48 25   2.9   1.6 | -58.5 -73.3  250  57 30   3.5   1.9
 36000 -56.5 -69.7  265  46 24   2.8   1.5 | -56.4 -69.5  250  58 30   3.4   1.9
 34000 -54.6 -66.3  265  44 23   6.5   3.6 | -54.2 -65.6  250  57 29   6.3   3.5
 32000 -50.1 -58.2  265  34 18   7.6   4.2 | -50.0 -58.0  245  44 22   7.0   3.9
 30000 -44.9 -48.8  260  24 12   7.8   4.3 | -45.1 -49.2  240  31 16   8.3   4.5
 29000 -42.6 -44.7  260  22 11   7.8   4.3 | -42.6 -44.7  245  29 15   8.3   4.6
 28000 -40.2 -40.4  260  19 10   7.8   4.3 | -40.2 -40.4  245  26 14   8.3   4.6
 27000 -37.9 -36.2  260  17  9   7.8   4.3 | -37.7 -35.9  245  24 12   8.2   4.5
 26000 -35.6 -32.1  250  15  8   7.7   4.2 | -35.3 -31.5  245  22 11   7.8   4.3
 25000 -33.3 -27.9  245  12  6   7.7   4.2 | -33.0 -27.4  240  20 10   7.8   4.3
 24000 -31.0 -23.8  230  11  5   7.7   4.2 | -30.6 -23.1  240  17  9   7.9   4.3
 23000 -28.5 -19.3  225  11  5   8.4   4.6 | -28.2 -18.8  240  17  8   8.1   4.5
 22000 -26.0 -14.8  225  11  6   8.4   4.6 | -25.8 -14.4  240  16  8   8.1   4.5
 21000 -23.5 -10.3  225  12  6   8.3   4.6 | -23.4 -10.1  240  15  8   7.8   4.3
 20000 -21.1  -6.0  230  12  6   8.1   4.5 | -21.2  -6.2  240  16  8   7.4   4.1
 19500 -19.8  -3.6  235  12  6   8.1   4.5 | -20.1  -4.2  245  16  8   7.4   4.1
 19000 -18.6  -1.5  235  12  6   8.1   4.5 | -19.0  -2.2  245  16  8   7.4   4.1
 18500 -17.4   0.7  240  13  7   8.0   4.4 | -17.9  -0.2  245  16  8   7.4   4.0
 18000 -16.4   2.5  240  12  6   6.8   3.7 | -16.8   1.8  245  16  8   7.1   3.9
 17500 -15.3   4.5  245  12  6   6.9   3.8 | -15.8   3.6  245  16  8   7.1   3.9
 17000 -14.3   6.3  250  12  6   6.9   3.8 | -14.7   5.5  245  15  8   7.5   4.1
 16500 -13.3   8.1  250  12  6   6.9   3.8 | -13.6   7.5  245  15  8   7.6   4.2
 16000 -12.3   9.9  250  12  6   6.9   3.8 | -11.8  10.8  240  14  7   8.4   4.6
 15500 -10.8  12.6  245  12  6   6.9   3.8 | -10.6  12.9  240  14  7   8.4   4.6
 15000  -9.8  14.4  245  11  6   7.1   3.9 |  -9.3  15.3  235  14  7   8.0   4.4
 14500  -8.7  16.3  240  10  5   7.2   3.9 |  -8.2  17.2  230  14  7   7.8   4.3
 14000  -7.7  18.1  230  10  5   7.4   4.1 |  -7.0  19.4  225  14  7   7.5   4.1
 13500  -6.5  20.3  220   9  5   7.7   4.2 |  -6.0  21.2  220  13  7   7.2   3.9
 13000  -5.4  22.3  205  10  5   7.8   4.3 |  -4.9  23.2  210  13  6   7.2   3.9
 12500  -4.2  24.4  200  10  5   8.1   4.5 |  -3.9  25.0  200  13  7   7.2   4.0
 12000  -3.0  26.6  190  10  5   8.3   4.6 |  -2.8  27.0  190  14  7   7.6   4.2
 11500  -1.7  28.9  195   9  4   9.4   5.2 |  -1.5  29.3  185  14  7   9.1   5.0
 11000  -0.3  31.5  195   7  4   9.2   5.1 |  -0.2  31.6  180  14  7   8.9   4.9
 10500   1.0  33.8  205   5  3   8.3   4.6 |   1.1  34.0  175  12  6   7.9   4.3
 10250   1.7  35.1  210   4  2   9.2   5.1 |   1.7  35.1  175  10  5   9.2   5.1
 10000   2.4  36.3  225   3  2  10.4   5.7 |   2.4  36.3  170   9  4  10.4   5.7
  9750   3.2  37.8  260   3  1   9.7   5.3 |   3.2  37.8  170   7  4   9.1   5.0
  9500   3.9  39.0  290   4  2   9.0   5.0 |   3.8  38.8  165   5  3   8.5   4.7
  9250   4.5  40.1  305   5  3   9.6   5.3 |   4.4  39.9  155   4  2   8.9   4.9
  9000   5.2  41.4  310   7  4   8.0   4.4 |   5.1  41.2  140   3  1   7.4   4.0
  8750   5.7  42.3  310   9  5   6.7   3.6 |   5.6  42.1  135   2  1   7.3   4.0
  8500   6.2  43.2  310  11  6   7.0   3.8 |   6.1  43.0  130   2  1   8.5   4.6
  8250   6.8  44.2  305  13  7   7.4   4.1 |   6.7  44.1  120   1  1   8.1   4.5
  8000   7.2  45.0  305  15  8   5.0   2.8 |   7.3  45.1  115   1  1   9.7   5.3
  7750   7.4  45.3  300  16  8   2.3   1.2 |   8.0  46.4  120   2  1   9.7   5.3
  7500   7.5  45.5  300  15  8   2.2   1.2 |   8.6  47.5  125   2  1   8.4   4.6
  7250   7.7  45.9  295  15  8   3.1   1.7 |   9.3  48.7  125   2  1   9.4   5.1
  7000   8.0  46.4  295  13  7   6.1   3.3 |  10.0  50.0  125   2  1  10.7   5.9
  6750   8.5  47.3  290  11  5   6.5   3.6 |  10.8  51.4  125   2  1  10.2   5.6
  6500   8.9  48.0  290   8  4   6.0   3.3 |  11.5  52.7  125   2  1   8.9   4.9
  6250   9.3  48.7  285   6  3   4.8   2.6 |  12.2  54.0  125   2  1  10.7   5.8
  6000   9.6  49.3  270   4  2   3.3   1.8 |  13.1  55.6  125   2  1  12.7   7.0
  5750   9.8  49.6  250   3  2   3.5   1.9 |  14.0  57.2  125   2  1  10.7   5.9
  5500  10.1  50.2  220   3  2   6.6   3.6 |  14.8  58.6  125   2  1  14.6   8.0

           04/25/2015 at 1500 MDT          |       04/25/2015 at 1800 MDT
                                           |
K index... +26.6  LI... +270.7             | K index... +26.0  LI... +272.4
CAPE... +343.2  CIN... -1.4                | CAPE... +45.6  CIN... -18.8
                                           |
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 -55.7 -68.3  240  37 19   0.5   0.3 | -55.9 -68.6  250  33 17   1.5   0.8
 45000 -54.9 -66.8  250  45 23   0.0   0.0 | -53.6 -64.5  255  39 20   0.5   0.3
 40000 -57.6 -71.7  245  55 28  -1.9  -1.0 | -57.6 -71.7  245  42 21  -2.7  -1.5
 38000 -57.9 -72.2  245  56 29   1.7   0.9 | -58.3 -72.9  245  40 21   1.3   0.7
 36000 -56.9 -70.4  245  55 28   1.7   0.9 | -57.5 -71.5  250  34 17   1.3   0.7
 34000 -55.7 -68.3  245  53 27   6.6   3.6 | -56.4 -69.5  250  27 14   7.5   4.1
 32000 -50.9 -59.6  245  42 22   8.0   4.4 | -51.1 -60.0  255  19 10   8.8   4.8
 30000 -45.4 -49.7  250  32 16   8.9   4.9 | -45.1 -49.2  255  12  6   9.2   5.0
 29000 -42.7 -44.9  245  30 15   9.0   4.9 | -42.4 -44.3  250  12  6   9.2   5.1
 28000 -40.0 -40.0  245  28 14   9.0   4.9 | -39.6 -39.3  250  13  6   9.2   5.1
 27000 -37.3 -35.1  240  26 14   8.7   4.8 | -36.9 -34.4  250  13  7   9.0   4.9
 26000 -34.9 -30.8  235  25 13   8.2   4.5 | -34.3 -29.7  245  14  7   8.6   4.7
 25000 -32.4 -26.3  230  24 12   8.2   4.5 | -31.7 -25.1  245  14  7   8.7   4.7
 24000 -30.0 -22.0  225  23 12   8.2   4.5 | -29.1 -20.4  240  15  8   8.6   4.7
 23000 -27.7 -17.9  225  21 11   7.4   4.1 | -26.8 -16.2  235  15  8   7.6   4.2
 22000 -25.5 -13.9  220  19 10   7.4   4.1 | -24.6 -12.3  230  15  8   7.6   4.2
 21000 -23.3  -9.9  215  17  9   7.4   4.0 | -22.3  -8.1  225  15  8   7.5   4.1
 20000 -21.2  -6.2  215  16  8   7.3   4.0 | -20.1  -4.2  215  16  8   7.5   4.1
 19500 -20.1  -4.2  215  15  8   7.3   4.0 | -19.0  -2.2  210  16  8   7.5   4.1
 19000 -19.0  -2.2  215  14  7   7.3   4.0 | -17.9  -0.2  205  16  8   7.5   4.1
 18500 -17.9  -0.2  210  13  7   7.4   4.0 | -16.8   1.8  200  17  9   7.4   4.1
 18000 -16.8   1.8  210  13  7   7.7   4.2 | -15.8   3.6  200  17  9   7.0   3.8
 17500 -15.7   3.7  210  13  7   7.6   4.2 | -14.7   5.5  195  18  9   7.0   3.9
 17000 -14.6   5.7  210  13  7   7.6   4.2 | -13.7   7.3  195  19 10   7.2   3.9
 16500 -13.4   7.9  205  14  7   7.6   4.2 | -12.6   9.3  195  19 10   7.2   4.0
 16000 -11.8  10.8  200  15  7   7.5   4.1 | -11.0  12.2  190  19 10   7.1   3.9
 15500 -10.7  12.7  195  15  8   7.5   4.1 | -10.0  14.0  190  20 10   7.1   3.9
 15000  -9.6  14.7  190  16  8   7.8   4.3 |  -9.0  15.8  190  20 10   7.2   3.9
 14500  -8.4  16.9  175  16  8   8.0   4.4 |  -7.9  17.8  190  20 10   7.2   3.9
 14000  -7.3  18.9  165  16  8   8.4   4.6 |  -6.9  19.6  190  20 10   7.3   4.0
 13500  -6.0  21.2  160  15  8   8.8   4.9 |  -5.8  21.6  190  19 10   7.4   4.1
 13000  -4.7  23.5  150  14  7   9.1   5.0 |  -4.7  23.5  190  18 10   7.5   4.1
 12500  -3.3  26.1  145  14  7   9.8   5.3 |  -3.6  25.5  190  17  9   7.6   4.2
 12000  -1.9  28.6  140  13  7   9.8   5.4 |  -2.5  27.5  190  16  8   7.6   4.2
 11500  -0.4  31.3  140  13  7  10.2   5.6 |  -1.4  29.5  190  15  8   7.8   4.3
 11000   1.1  34.0  140  12  6  10.0   5.5 |  -0.3  31.5  185  13  7   7.7   4.2
 10500   2.5  36.5  140  12  6   8.6   4.7 |   0.7  33.3  190  12  6   6.5   3.6
 10250   3.1  37.6  140  12  6   9.9   5.4 |   1.2  34.2  190  11  5   7.4   4.1
 10000   4.0  39.2  140  11  6  11.2   6.1 |   1.8  35.2  190   9  5   9.1   5.0
  9750   4.8  40.6  140  11  6  10.6   5.8 |   2.5  36.5  190   8  4   9.2   5.0
  9500   5.5  41.9  140  11  6  10.6   5.8 |   3.2  37.8  195   7  4   8.8   4.8
  9250   6.3  43.3  140  11  6  10.1   5.6 |   3.8  38.8  195   6  3   9.0   4.9
  9000   7.0  44.6  140  11  5   8.5   4.7 |   4.5  40.1  200   5  3   8.5   4.7
  8750   7.7  45.9  140  10  5   8.9   4.9 |   5.1  41.2  205   4  2   7.8   4.3
  8500   8.4  47.1  140  10  5  10.1   5.5 |   5.7  42.3  215   3  2   7.9   4.3
  8250   9.1  48.4  140  10  5   9.3   5.1 |   6.2  43.2  235   3  1   7.7   4.2
  8000   9.8  49.6  140  10  5  11.5   6.3 |   6.8  44.2  260   2  1   8.3   4.6
  7750  10.7  51.3  135   9  5  11.0   6.0 |   7.4  45.3  305   3  2   6.9   3.8
  7500  11.4  52.5  135   9  5   8.6   4.7 |   7.8  46.0  320   4  2   5.3   2.9
  7250  12.1  53.8  135   9  5   9.3   5.1 |   8.2  46.8  325   6  3   5.3   2.9
  7000  12.8  55.0  135   9  4   9.7   5.3 |   8.5  47.3  325   8  4   2.3   1.3
  6750  13.6  56.5  135   8  4  10.4   5.7 |   8.5  47.3  325  10  5   0.3   0.2
  6500  14.3  57.7  135   8  4  10.5   5.8 |   8.6  47.5  320  14  7   0.0   0.0
  6250  15.1  59.2  135   8  4  10.2   5.6 |   8.6  47.5  320  18  9   1.3   0.7
  6000  15.9  60.6  135   8  4  10.2   5.6 |   8.7  47.7  320  18  9   2.6   1.4
  5750  16.6  61.9  135   7  4   9.9   5.4 |   8.8  47.8  315  18  9   4.6   2.5
  5500  17.5  63.5  135   6  3  15.5   8.5 |   9.3  48.7  320  15  8  11.0   6.0
________________________________________________________________________________

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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