Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 170025
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1825 MDT Sunday, April 16, 2017

This forecast is for Monday, April 17, 2017:

If the trigger temperature of 65.3 F/18.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1284 ft/min (6.5 m/s)
   Maximum height of thermals.................. 19244 ft MSL (13937 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13314 ft MSL (8007 ft AGL)
Thermal soaring outlook for Tuesday 04/18...... Excellent

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....................... 27672 ft MSL (22365 ft AGL)
Wave soaring outlook for Tuesday 04/18......... Poor

Remarks...

Sunrise/Sunset.................... 06:18:35 / 19:39:02 MDT
Total possible sunshine........... 13 hr 20 min 28 sec (800 min 28 sec)
Altitude of sun at 12:58:59 MDT... 60.98 degrees

Upper air data from numerical model forecast valid on 04/17/2017 at 0600 MDT

Freezing level.................. 12414 ft MSL (7107 ft AGL)
Convective condensation level... 15248 ft MSL (9941 ft AGL)
Lifted condensation level....... 16258 ft MSL (10951 ft AGL)
Lifted index.................... -3.2
K index......................... +12.5

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  -60.9 -77.6   285   28   14  -0.5  -0.3      M     M       M      M    M
 45000  -61.7 -79.1   280   30   15  -0.8  -0.4      M     M       M      M    M
 40000  -65.4 -85.7   290   30   15  -2.5  -1.4      M     M       M      M    M
 38000  -63.1 -81.6   295   28   14   7.7   4.2      M     M       M      M    M
 36000  -58.4 -73.1   295   24   13   7.7   4.2      M     M       M      M    M
 34000  -53.6 -64.5   295   21   11   8.8   4.8      M     M       M      M    M
 32000  -48.3 -54.9   295   17    9   8.8   4.8      M     M       M      M    M
 30000  -42.5 -44.5   290   16    8   8.3   4.6   32.4  90.3     5.6      M    M
 29000  -40.0 -40.0   285   17    9   8.3   4.6   31.8  89.2     5.2      M    M
 28000  -37.5 -35.5   285   18    9   8.3   4.6   31.3  88.3     4.9      M    M
 27000  -35.1 -31.2   280   19   10   8.2   4.5   30.8  87.4     4.5      M    M
 26000  -32.6 -26.7   275   20   10   8.2   4.5   30.1  86.2     4.0      M    M
 25000  -30.2 -22.4   275   20   10   8.2   4.5   29.6  85.2     3.6      M    M
 24000  -27.8 -18.0   270   21   11   7.4   4.1   29.0  84.2     3.2      M    M
 23000  -25.5 -13.9   265   21   11   7.6   4.1   28.1  82.6     2.5      M    M
 22000  -23.3  -9.9   265   22   11   7.6   4.2   27.3  81.2     1.9      M    M
 21000  -21.1  -6.0   265   22   11   7.6   4.2   26.6  79.9     1.2      M    M
 20000  -18.8  -1.8   265   23   12   7.6   4.2   25.8  78.4     0.5      M    M
 19500  -17.7   0.1   265   23   12   7.6   4.2   25.4  77.8     0.2      M    M
 19000  -16.6   2.1   270   23   12   7.6   4.2   25.1  77.2    -0.1   1267  6.4
 18500  -15.4   4.3   270   23   12   8.2   4.5   24.8  76.6    -0.4   1217  6.2
 18000  -14.2   6.4   270   23   12   8.2   4.5   24.5  76.1    -0.6   1166  5.9
 17500  -13.0   8.6   270   23   12   8.2   4.5   24.2  75.6    -0.9   1114  5.7
 17000  -11.7  10.9   275   23   12   8.2   4.5   24.0  75.1    -1.1   1063  5.4
 16500  -10.5  13.1   275   22   12   8.2   4.5   23.7  74.7    -1.3   1011  5.1
 16000   -9.3  15.3   275   22   11   8.2   4.5   23.4  74.2    -1.6    960  4.9
 15500   -7.4  18.7   280   21   11   8.2   4.5   23.1  73.5    -2.0    883  4.5
 15000   -6.2  20.8   280   21   11   8.3   4.5   22.8  73.0    -2.2    832  4.2
 14500   -5.0  23.0   275   20   10   8.3   4.6   22.6  72.6    -2.5    780  4.0
 14000   -3.8  25.2   275   19   10   8.6   4.7   22.3  72.2    -2.7    729  3.7
 13500   -2.5  27.5   275   17    9   8.6   4.7   22.1  71.9    -3.0    676  3.4
 13000   -1.3  29.7   270   16    8   8.5   4.6   21.9  71.5    -3.2    624  3.2
 12500   -0.1  31.8   265   15    8   8.6   4.7   21.7  71.1    -3.4    572  2.9
 12000    1.1  34.0   260   13    7   7.3   4.0   21.4  70.6    -3.7    523  2.7
 11500    2.2  36.0   255   12    6   7.4   4.1   21.1  69.9    -4.1    475  2.4
 11000    3.3  37.9   250   11    6   7.4   4.1   20.7  69.3    -4.5    428  2.2
 10500    4.3  39.7   240   10    5   8.3   4.5   20.3  68.6    -5.0    382  1.9
 10250    4.9  40.8   235    9    5   4.0   2.2   20.1  68.2    -5.2    359  1.8
 10000    5.0  41.0   230    9    5   4.5   2.5   19.5  67.2    -5.8    347  1.8
  9750    5.6  42.1   225    8    4   9.1   5.0   19.4  66.9    -5.9    322  1.6
  9500    6.2  43.2   215    8    4   8.1   4.4   19.3  66.7    -6.1    297  1.5
  9250    6.8  44.2   205    7    4   7.0   3.8   19.1  66.5    -6.3    272  1.4
  9000    7.2  45.0   200    7    4   6.8   3.7   18.9  66.0    -6.5    251  1.3
  8750    7.8  46.0   200    6    3   8.3   4.5   18.7  65.7    -6.7    227  1.2
  8500    8.4  47.1   195    6    3   8.0   4.4   18.6  65.5    -6.9    202  1.0
  8250    9.0  48.2   190    6    3   7.5   4.1   18.4  65.2    -7.0    177  0.9
  8000    9.5  49.1   190    5    2   7.2   3.9   18.3  64.9    -7.2    153  0.8
  7750   10.1  50.2   190    4    2   7.4   4.1   18.1  64.5    -7.4    129  0.7
  7500   10.6  51.1   190    3    2   6.4   3.5   17.9  64.2    -7.6    106  0.5
  7250   11.0  51.8   200    3    1   5.1   2.8   17.5  63.6    -8.0     86  0.4
  7000   11.4  52.5   215    2    1   4.9   2.7   17.2  62.9    -8.4     67  0.3
  6750   11.7  53.1   230    2    1   5.0   2.8   16.8  62.3    -8.7     49  0.2
  6500   12.0  53.6   255    2    1  -0.7  -0.4   16.3  61.4    -9.3     35  0.2
  6250   11.6  52.9   280    2    1  -5.6  -3.1   15.3  59.5   -10.4     38  0.2
  6000   11.3  52.3   295    3    1  -2.3  -1.3   14.2  57.6   -11.5     41  0.2
  5750   11.0  51.8   310    4    2  -8.9  -4.9   13.2  55.7   -12.5     43  0.2
  5500    9.5  49.1   300    3    1 -27.8 -15.3   11.1  52.0   -14.7     79  0.4

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

           04/17/2017 at 0900 MDT          |       04/17/2017 at 1200 MDT
                                           |
K index... +10.0  LI... +1.5               | K index... +8.5  LI... -0.8
CAPE... 0.0  CIN... 0.0                    | CAPE... +72.1  CIN... -52.4
                                           |
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 -61.6 -78.9  300  29 15  -0.7  -0.4 | -61.7 -79.1  300  30 15   0.1   0.0
 45000 -62.7 -80.9  300  35 18  -1.1  -0.6 | -61.6 -78.9  300  38 19  -0.6  -0.3
 40000 -64.5 -84.1  290  30 16  -1.3  -0.7 | -62.7 -80.9  290  36 18  -0.8  -0.4
 38000 -62.2 -80.0  280  29 15   6.9   3.8 | -60.6 -77.1  285  36 19   6.0   3.3
 36000 -58.1 -72.6  275  29 15   6.9   3.8 | -57.1 -70.8  285  37 19   5.9   3.3
 34000 -53.6 -64.5  270  28 14   8.9   4.9 | -53.0 -63.4  280  37 19   8.7   4.8
 32000 -48.2 -54.8  270  25 13   9.0   4.9 | -47.1 -52.8  275  35 18   8.7   4.8
 30000 -42.2 -44.0  270  22 12   8.6   4.7 | -41.8 -43.2  270  32 17   8.8   4.8
 29000 -39.7 -39.5  270  21 11   8.6   4.7 | -39.2 -38.6  265  31 16   8.8   4.8
 28000 -37.1 -34.8  270  21 11   8.6   4.7 | -36.5 -33.7  260  30 15   8.8   4.8
 27000 -34.7 -30.5  265  20 11   7.5   4.1 | -34.0 -29.2  260  29 15   7.4   4.0
 26000 -32.4 -26.3  265  22 11   7.6   4.2 | -31.8 -25.2  255  28 15   7.4   4.1
 25000 -30.1 -22.2  260  23 12   7.6   4.2 | -29.6 -21.3  255  28 14   7.5   4.1
 24000 -27.9 -18.2  260  24 13   7.4   4.1 | -27.4 -17.3  250  27 14   7.4   4.1
 23000 -25.7 -14.3  255  24 13   7.5   4.1 | -25.2 -13.4  250  27 14   7.4   4.1
 22000 -23.5 -10.3  255  25 13   7.5   4.1 | -22.9  -9.2  255  27 14   7.5   4.1
 21000 -21.2  -6.2  255  25 13   7.8   4.3 | -20.7  -5.3  255  26 14   7.5   4.1
 20000 -18.9  -2.0  260  25 13   7.8   4.3 | -18.5  -1.3  255  25 13   7.5   4.1
 19500 -17.7   0.1  265  25 13   7.8   4.3 | -17.4   0.7  255  25 13   7.5   4.1
 19000 -16.6   2.1  265  25 13   7.8   4.3 | -16.3   2.7  255  24 12   7.4   4.1
 18500 -15.3   4.5  270  24 12   8.7   4.7 | -15.1   4.8  255  24 12   8.1   4.4
 18000 -14.0   6.8  270  23 12   8.6   4.7 | -13.9   7.0  255  23 12   8.0   4.4
 17500 -12.8   9.0  270  22 11   8.0   4.4 | -12.7   9.1  255  22 11   7.8   4.3
 17000 -11.6  11.1  275  21 11   7.7   4.2 | -11.0  12.2  255  22 11   7.7   4.2
 16500 -10.5  13.1  275  21 11   7.8   4.3 |  -9.8  14.4  255  22 11   8.1   4.4
 16000  -8.7  16.3  275  20 10   8.2   4.5 |  -8.6  16.5  260  21 11   8.2   4.5
 15500  -7.5  18.5  280  20 10   8.2   4.5 |  -7.4  18.7  260  21 11   8.3   4.6
 15000  -6.2  20.8  280  19 10   8.2   4.5 |  -6.1  21.0  260  20 11   8.6   4.7
 14500  -5.0  23.0  280  18 10   8.3   4.5 |  -4.9  23.2  260  20 10   8.6   4.7
 14000  -3.8  25.2  280  18  9   8.5   4.7 |  -3.6  25.5  260  19 10   8.8   4.8
 13500  -2.5  27.5  280  17  9   8.5   4.7 |  -2.3  27.9  260  17  9   8.8   4.8
 13000  -1.2  29.8  275  15  8   9.1   5.0 |  -1.0  30.2  260  16  8   8.7   4.8
 12500   0.1  32.2  275  14  7   9.1   5.0 |   0.3  32.5  260  14  7   8.7   4.8
 12000   1.4  34.5  270  12  6   8.5   4.7 |   1.6  34.9  255  13  7   8.9   4.9
 11500   2.7  36.9  265  11  5   8.7   4.7 |   3.0  37.4  250  11  6   8.8   4.9
 11000   3.9  39.0  255   9  5   8.0   4.4 |   4.3  39.7  245  10  5   9.1   5.0
 10500   5.1  41.2  240   8  4   8.9   4.9 |   5.6  42.1  240  10  5   9.8   5.4
 10250   5.7  42.3  235   8  4   4.2   2.3 |   6.3  43.3  235   9  5   6.2   3.4
 10000   5.9  42.6  230   8  4   4.5   2.5 |   6.7  44.1  235   9  5   6.7   3.6
  9750   6.5  43.7  220   8  4   9.3   5.1 |   7.4  45.3  230   9  5  10.4   5.7
  9500   7.1  44.8  210   8  4   8.3   4.5 |   8.1  46.6  225   9  5   9.9   5.5
  9250   7.7  45.9  200   9  5   7.0   3.8 |   8.8  47.8  220   9  5   7.8   4.3
  9000   8.1  46.6  195   9  5   6.0   3.3 |   9.3  48.7  215   9  5   7.0   3.8
  8750   8.6  47.5  190  10  5   6.8   3.7 |   9.9  49.8  205   9  4   8.9   4.9
  8500   9.0  48.2  180  10  5   6.7   3.7 |  10.5  50.9  200   8  4   8.5   4.6
  8250   9.5  49.1  175  10  5   6.9   3.8 |  11.1  52.0  190   8  4   8.6   4.7
  8000  10.0  50.0  175  11  5   6.7   3.7 |  11.6  52.9  185   8  4   8.5   4.7
  7750  10.5  50.9  170  11  6   6.7   3.7 |  12.2  54.0  185   7  4   8.2   4.5
  7500  10.9  51.6  170  11  6   5.1   2.8 |  12.8  55.0  180   7  4   9.0   4.9
  7250  11.2  52.2  170  11  5   3.2   1.8 |  13.5  56.3  180   7  4  10.5   5.8
  7000  11.4  52.5  170  10  5   3.1   1.7 |  14.3  57.7  180   7  3  10.7   5.9
  6750  11.6  52.9  170  10  5   3.3   1.8 |  15.0  59.0  180   7  3   9.3   5.1
  6500  11.7  53.1  170   9  5  -0.7  -0.4 |  15.7  60.3  180   6  3  10.0   5.5
  6250  11.5  52.7  170   7  4  -3.1  -1.7 |  16.5  61.7  180   6  3  11.8   6.5
  6000  11.2  52.2  175   5  3  -4.3  -2.4 |  17.4  63.3  180   6  3  10.3   5.7
  5750  11.0  51.8  180   3  2   1.6   0.9 |  18.2  64.8  180   6  3  13.4   7.4
  5500  11.8  53.2  190   2  1  20.5  11.3 |  19.6  67.3  180   6  3  24.0  13.2

           04/17/2017 at 1500 MDT          |       04/17/2017 at 1800 MDT
                                           |
K index... +16.3  LI... +0.3               | K index... +18.0  LI... -0.2
CAPE... 0.0  CIN... -0.1                   | CAPE... +0.9  CIN... -5.2
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.3 -81.9  305  39 20   0.8   0.4 | -63.3 -81.9  310  42 21   1.1   0.6
 45000 -62.2 -80.0  305  44 23  -0.0  -0.0 | -61.8 -79.2  310  48 24  -0.9  -0.5
 40000 -62.2 -80.0  300  41 21   0.0   0.0 | -62.9 -81.2  310  60 31  -0.7  -0.4
 38000 -60.0 -76.0  290  39 20   5.6   3.0 | -60.4 -76.7  310  58 30   6.9   3.8
 36000 -56.6 -69.9  285  38 20   5.6   3.0 | -55.7 -68.3  310  52 27   6.9   3.8
 34000 -52.0 -61.6  280  38 19   8.9   4.9 | -51.1 -60.0  305  45 23   8.7   4.8
 32000 -46.6 -51.9  275  37 19   8.9   4.9 | -45.9 -50.6  295  37 19   8.7   4.8
 30000 -41.2 -42.2  270  35 18   9.3   5.1 | -40.6 -41.1  285  33 17   9.1   5.0
 29000 -38.4 -37.1  270  33 17   9.3   5.1 | -37.9 -36.2  285  32 16   9.1   5.0
 28000 -35.6 -32.1  270  31 16   9.3   5.1 | -35.1 -31.2  285  31 16   9.1   5.0
 27000 -33.0 -27.4  265  30 16   8.2   4.5 | -32.5 -26.5  285  30 16   8.0   4.4
 26000 -30.5 -22.9  265  32 16   8.3   4.5 | -30.1 -22.2  285  31 16   8.1   4.4
 25000 -28.1 -18.6  265  33 17   8.3   4.5 | -27.7 -17.9  285  32 16   8.1   4.4
 24000 -25.7 -14.3  260  34 18   6.6   3.6 | -25.4 -13.7  285  32 17   6.1   3.4
 23000 -23.7 -10.7  260  34 18   6.8   3.7 | -23.6 -10.5  275  32 17   6.2   3.4
 22000 -21.7  -7.1  255  34 18   6.8   3.7 | -21.7  -7.1  270  32 17   6.3   3.4
 21000 -19.7  -3.5  255  34 18   6.4   3.5 | -19.9  -3.8  265  33 17   6.6   3.6
 20000 -17.8  -0.0  250  34 18   6.5   3.6 | -17.9  -0.2  265  32 17   6.6   3.6
 19500 -16.8   1.8  250  34 17   6.5   3.6 | -17.0   1.4  260  32 17   6.6   3.6
 19000 -15.9   3.4  250  34 17   6.4   3.5 | -16.0   3.2  260  32 17   6.4   3.5
 18500 -14.8   5.4  250  33 17   7.7   4.2 | -14.3   6.3  255  30 16   8.2   4.5
 18000 -13.7   7.3  250  31 16   7.6   4.2 | -13.1   8.4  255  28 15   8.3   4.5
 17500 -12.0  10.4  250  28 15   8.6   4.7 | -11.8  10.8  250  27 14   8.5   4.7
 17000 -10.7  12.7  250  27 14   8.5   4.7 | -10.6  12.9  250  25 13   8.5   4.7
 16500  -9.5  14.9  245  25 13   8.7   4.8 |  -9.3  15.3  250  23 12   9.3   5.1
 16000  -8.1  17.4  245  25 13   8.8   4.8 |  -7.8  18.0  250  22 11   9.6   5.3
 15500  -6.8  19.8  240  24 12   8.9   4.9 |  -6.4  20.5  245  21 11   9.6   5.3
 15000  -5.5  22.1  235  23 12   9.3   5.1 |  -5.0  23.0  245  21 11   9.5   5.2
 14500  -4.1  24.6  235  22 11   9.3   5.1 |  -3.5  25.7  245  21 11   9.5   5.2
 14000  -2.7  27.1  230  21 11   9.3   5.1 |  -2.1  28.2  240  20 10   9.5   5.2
 13500  -1.3  29.7  230  20 10   9.3   5.1 |  -0.7  30.7  240  20 10   9.5   5.2
 13000   0.1  32.2  225  19 10   9.2   5.0 |   0.8  33.4  240  19 10   9.5   5.2
 12500   1.5  34.7  225  17  9   9.2   5.1 |   2.2  36.0  235  18  9   9.5   5.2
 12000   2.8  37.0  220  16  8   8.9   4.9 |   3.6  38.5  235  17  9   9.2   5.0
 11500   4.2  39.6  220  15  8   9.0   4.9 |   5.0  41.0  235  16  8   9.2   5.0
 11000   5.4  41.7  215  14  7   7.9   4.3 |   6.3  43.3  235  14  7   8.9   4.9
 10500   6.6  43.9  215  13  6   6.9   3.8 |   7.6  45.7  235  13  7   8.3   4.5
 10250   7.2  45.0  210  12  6  11.6   6.4 |   8.3  46.9  235  13  7  11.2   6.1
 10000   8.2  46.8  210  11  6  12.8   7.0 |   9.2  48.6  235  13  7  11.6   6.4
  9750   9.0  48.2  210  11  6   8.9   4.9 |  10.0  50.0  240  12  6   9.0   4.9
  9500   9.7  49.5  210  11  6  10.0   5.5 |  10.7  51.3  240  12  6   9.9   5.4
  9250  10.4  50.7  210  10  5   9.4   5.2 |  11.4  52.5  240  12  6   9.1   5.0
  9000  11.1  52.0  210  10  5   9.7   5.3 |  12.1  53.8  240  12  6   9.8   5.4
  8750  11.9  53.4  210  10  5  10.1   5.5 |  12.9  55.2  240  11  6  10.7   5.9
  8500  12.6  54.7  210  10  5   9.8   5.4 |  13.7  56.7  240  11  6  10.6   5.8
  8250  13.4  56.1  210  10  5  11.0   6.0 |  14.4  57.9  240  11  6  10.3   5.7
  8000  14.2  57.6  210  10  5  10.7   5.9 |  15.2  59.4  240  11  6   9.6   5.2
  7750  14.9  58.8  215  10  5   8.8   4.8 |  15.9  60.6  240  11  6   9.2   5.0
  7500  15.6  60.1  215   9  5   9.2   5.0 |  16.6  61.9  240  11  5   9.3   5.1
  7250  16.4  61.5  215   9  5  10.9   6.0 |  17.3  63.1  245  10  5  10.5   5.8
  7000  17.2  63.0  215   9  5  11.4   6.3 |  18.1  64.6  245  10  5  11.0   6.1
  6750  18.0  64.4  215   9  5   9.5   5.2 |  18.9  66.0  245  10  5   9.9   5.4
  6500  18.7  65.7  215   9  4   9.8   5.4 |  19.7  67.5  245  10  5   9.7   5.3
  6250  19.5  67.1  215   8  4  11.4   6.3 |  20.4  68.7  245   9  5  10.1   5.6
  6000  20.3  68.5  215   8  4  10.9   6.0 |  21.2  70.2  245   9  5  10.2   5.6
  5750  21.1  70.0  215   8  4  11.8   6.5 |  21.9  71.4  245   9  4   9.5   5.2
  5500  22.3  72.1  215   8  4  19.5  10.7 |  22.6  72.7  250   8  4  10.5   5.8
________________________________________________________________________________

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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