Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 211314
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0714 MDT Thursday, May 21, 2015

This forecast is for Thursday, May 21, 2015:

If the trigger temperature of 54.4 F/12.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 218 ft/min (1.1 m/s)
   Maximum height of thermals.................. 10101 ft MSL (4816 ft AGL)

Forecast maximum temperature................... 58.0 F/14.9 C
Time of trigger temperature.................... 1345 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8881 ft MSL (3596 ft AGL)
Thermal soaring outlook for Friday 05/22....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 39040 ft MSL (33755 ft AGL)
Wave soaring outlook for Friday 05/22.......... Fair

Remarks...

Sunrise/Sunset.................... 05:40:10 / 20:11:47 MDT
Total possible sunshine........... 14 hr 31 min 37 sec (871 min 37 sec)
Altitude of sun at 12:56:11 MDT... 70.45 degrees

Upper air data from rawinsonde observation taken on 05/21/2015 at 0600 MDT

Freezing level.................. 8341 ft MSL (3056 ft AGL)
Additional freezing levels...... 8588 ft MSL (3303 ft AGL)
                                 9707 ft MSL (4422 ft AGL)
Convective condensation level... 13301 ft MSL (8016 ft AGL)
Lifted condensation level....... 10704 ft MSL (5419 ft AGL)
Lifted index.................... +3.4
K index......................... +15.0

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  -57.0 -70.6   265   23   12 -13.5  -7.4  104.4 219.9    51.5      M    M
 45000  -60.3 -76.5   250   62   32  -0.0  -0.0   74.1 165.4    36.6      M    M
 40000  -63.0 -81.4   260   85   44   5.6   3.1   46.5 115.8    21.1      M    M
 38000  -59.7 -75.5   260   90   46   5.4   3.0   42.7 108.9    19.1      M    M
 36000  -55.6 -68.1   255   82   42   7.6   4.2   40.1 104.2    17.8      M    M
 34000  -50.7 -59.3   255   74   38   9.5   5.2   38.9 102.0    17.4      M    M
 32000  -45.6 -50.1   250   69   36   7.3   4.0   36.8  98.2    16.4      M    M
 30000  -41.9 -43.4   250   65   33   8.9   4.9   34.0  93.2    14.7      M    M
 29000  -39.1 -38.4   250   63   33   9.2   5.0   33.7  92.7    14.7      M    M
 28000  -36.4 -33.5   250   62   32   8.9   4.9   33.6  92.4    14.8      M    M
 27000  -33.9 -29.0   250   54   28   8.1   4.4   32.9  91.3    14.4      M    M
 26000  -31.6 -24.9   250   46   24   7.0   3.8   32.1  89.9    14.0      M    M
 25000  -29.7 -21.5   250   38   20   7.8   4.3   30.9  87.7    13.2      M    M
 24000  -27.0 -16.6   245   37   19   8.1   4.4   30.7  87.2    13.1      M    M
 23000  -24.6 -12.3   245   38   19   8.1   4.4   30.1  86.1    12.7      M    M
 22000  -23.0  -9.4   245   38   20   4.7   2.6   28.4  83.2    11.5      M    M
 21000  -21.2  -6.2   250   36   19   7.9   4.3   27.1  80.8    10.5      M    M
 20000  -18.8  -1.8   255   35   18   7.7   4.2   26.5  79.6    10.1      M    M
 19500  -17.8  -0.0   260   34   18   6.4   3.5   25.9  78.7     9.7      M    M
 19000  -16.9   1.6   270   34   17   7.2   3.9   25.4  77.7     9.2      M    M
 18500  -15.7   3.7   270   34   18   8.2   4.5   25.1  77.2     9.0      M    M
 18000  -14.6   5.7   270   34   18   6.8   3.7   24.7  76.4     8.7      M    M
 17500  -13.5   7.7   270   34   18   8.2   4.5   24.3  75.7     8.4      M    M
 17000  -12.2  10.0   270   35   18   8.4   4.6   24.0  75.2     8.2      M    M
 16500  -11.0  12.2   270   35   18   8.4   4.6   23.8  74.8     8.0      M    M
 16000   -9.1  15.6   270   35   18   8.0   4.4   23.4  74.2     7.8      M    M
 15500   -8.0  17.6   270   35   18   7.9   4.3   23.1  73.6     7.5      M    M
 15000   -6.8  19.8   270   34   17   7.9   4.3   22.8  73.1     7.2      M    M
 14500   -5.7  21.7   270   27   14   7.9   4.4   22.5  72.5     6.9      M    M
 14000   -4.5  23.9   270   21   11   8.2   4.5   22.2  72.0     6.7      M    M
 13500   -3.3  26.1   270   18    9   8.2   4.5   22.0  71.6     6.5      M    M
 13000   -2.1  28.2   270   15    8   8.2   4.5   21.8  71.2     6.3      M    M
 12500   -0.9  30.4   280   13    7   8.2   4.5   21.5  70.7     6.0      M    M
 12000    0.3  32.5   285   12    6   8.1   4.4   21.2  70.2     5.8      M    M
 11500    1.5  34.7   275   10    5   6.4   3.5   21.0  69.8     5.5      M    M
 11000    1.5  34.7   260    9    5  -2.7  -1.5   19.5  67.0     4.1      M    M
 10500    0.8  33.4   245    8    4  -9.4  -5.2   17.2  63.0     2.0      M    M
 10250    0.0  32.0   235    8    4  -7.7  -4.2   15.6  60.2     0.5      M    M
 10000   -0.3  31.5   225   10    5   1.3   0.7   14.6  58.4    -0.6    319  1.6
  9750   -0.0  32.0   220   13    7   4.2   2.3   14.1  57.5    -1.1    304  1.5
  9500    0.2  32.4   220   15    8   3.1   1.7   13.7  56.6    -1.6    290  1.5
  9250    0.5  32.9   215   18    9   4.6   2.5   13.2  55.7    -2.0    275  1.4
  9000    0.7  33.3   215   20   10  -0.5  -0.3   12.7  54.8    -2.5    261  1.3
  8750    0.3  32.5   215   17    9  -8.9  -4.9   11.5  52.7    -3.7    266  1.3
  8500   -0.2  31.6   215   14    7  -0.9  -0.5   10.2  50.4    -4.9    273  1.4
  8250    0.1  32.2   220   12    6   6.0   3.3    9.8  49.7    -5.3    256  1.3
  8000    0.5  32.9   220    9    5   4.2   2.3    9.4  49.0    -5.7    238  1.2
  7750    0.8  33.4   220    7    4   4.7   2.6    9.0  48.2    -6.1    221  1.1
  7500    1.1  34.0   220    5    3   4.5   2.5    8.6  47.5    -6.6    203  1.0
  7250    1.5  34.7   220    3    2   4.6   2.5    8.2  46.8    -7.0    186  0.9
  7000    1.8  35.2   230    1    1   4.6   2.5    7.8  46.1    -7.4    169  0.9
  6750    2.1  35.8   000    0    0   4.6   2.5    7.4  45.4    -7.8    151  0.8
  6500    2.5  36.5   345    1    0   4.6   2.5    7.0  44.7    -8.2    134  0.7
  6250    2.8  37.0   010    1    1   4.6   2.5    6.6  44.0    -8.6    116  0.6
  6000    3.1  37.6   015    2    1   4.7   2.6    6.3  43.3    -9.0     99  0.5
  5750    3.6  38.5   355    2    1   7.7   4.2    6.0  42.7    -9.4     79  0.4
  5500    4.3  39.7   345    3    2  12.3   6.7    6.0  42.8    -9.4     50  0.3

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

           05/21/2015 at 0900 MDT          |       05/21/2015 at 1200 MDT
                                           |
K index... +15.3  LI... +273.5             | K index... +18.7  LI... +272.9
CAPE... 0.0  CIN... -49.8                  | CAPE... +24.0  CIN... -114.0
                                           |
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 -58.5 -73.3  260  31 16   0.3   0.2 | -59.2 -74.6  260  33 17   0.1   0.1
 45000 -58.2 -72.8  260  52 27  -2.5  -1.4 | -59.1 -74.4  260  58 30  -1.1  -0.6
 40000 -61.4 -78.5  265  79 41  -2.2  -1.2 | -60.5 -76.9  255  81 42  -0.9  -0.5
 38000 -59.2 -74.6  265  80 41   6.7   3.7 | -58.1 -72.6  255  81 42   6.3   3.5
 36000 -55.2 -67.4  260  76 39   6.7   3.7 | -53.9 -65.0  255  76 39   6.3   3.5
 34000 -50.5 -58.9  260  69 36   7.2   3.9 | -49.7 -57.5  255  69 36   7.7   4.2
 32000 -46.2 -51.2  255  60 31   7.2   3.9 | -45.1 -49.2  250  60 31   7.6   4.2
 30000 -41.4 -42.5  250  49 25   9.0   4.9 | -40.3 -40.5  250  52 27   8.5   4.7
 29000 -38.7 -37.7  250  44 23   9.0   4.9 | -37.7 -35.9  250  48 25   8.5   4.7
 28000 -36.0 -32.8  245  39 20   9.0   4.9 | -35.2 -31.4  255  45 23   8.5   4.6
 27000 -33.7 -28.7  245  35 18   5.7   3.1 | -33.0 -27.4  255  41 21   5.6   3.0
 26000 -31.9 -25.4  245  34 17   5.9   3.2 | -31.2 -24.2  250  36 19   5.7   3.1
 25000 -30.1 -22.2  250  33 17   5.9   3.2 | -29.5 -21.1  245  31 16   5.7   3.1
 24000 -28.3 -18.9  255  31 16   6.6   3.6 | -27.7 -17.9  240  28 14   8.0   4.4
 23000 -26.4 -15.5  255  28 15   6.6   3.6 | -25.3 -13.5  240  27 14   7.9   4.4
 22000 -24.4 -11.9  255  26 13   6.6   3.6 | -23.0  -9.4  245  26 13   8.0   4.4
 21000 -22.2  -8.0  255  24 12   8.7   4.8 | -20.7  -5.3  245  24 13   7.3   4.0
 20000 -19.6  -3.3  260  23 12   8.6   4.7 | -18.5  -1.3  245  22 11   7.3   4.0
 19500 -18.3  -0.9  260  23 12   8.6   4.7 | -17.4   0.7  250  20 10   7.3   4.0
 19000 -17.0   1.4  265  22 12   8.6   4.7 | -16.4   2.5  250  19 10   7.4   4.1
 18500 -15.7   3.7  265  23 12   9.3   5.1 | -14.9   5.2  250  17  9   6.6   3.6
 18000 -14.3   6.3  270  23 12   9.3   5.1 | -13.9   7.0  250  17  9   6.6   3.6
 17500 -12.3   9.9  270  24 12   8.6   4.7 | -12.9   8.8  255  16  8   6.5   3.6
 17000 -11.0  12.2  270  24 12   8.7   4.8 | -11.9  10.6  260  16  8   6.5   3.5
 16500  -9.7  14.5  270  24 12   8.7   4.8 | -10.9  12.4  260  15  8   8.0   4.4
 16000  -8.4  16.9  270  23 12   8.7   4.7 |  -9.7  14.5  260  13  7   8.5   4.7
 15500  -7.2  19.0  270  23 12   8.6   4.7 |  -8.4  16.9  260  12  6   9.3   5.1
 15000  -5.9  21.4  275  21 11   8.4   4.6 |  -6.8  19.8  260  10  5  10.7   5.9
 14500  -4.7  23.5  275  18  9   8.4   4.6 |  -5.2  22.6  255   9  5  10.6   5.8
 14000  -3.4  25.9  280  17  9   8.2   4.5 |  -3.7  25.3  255   8  4   9.6   5.3
 13500  -2.2  28.0  285  16  8   8.2   4.5 |  -2.2  28.0  255   7  3   9.7   5.3
 13000  -1.0  30.2  290  15  8   8.3   4.6 |  -0.8  30.6  255   6  3   9.0   5.0
 12500   0.2  32.4  290  13  7   8.3   4.6 |   0.5  32.9  260   4  2   9.3   5.1
 12000   1.4  34.5  295  11  6   7.9   4.3 |   1.8  35.2  260   3  2   7.6   4.2
 11500   2.5  36.5  290  10  5   8.1   4.5 |   2.9  37.2  255   2  1   7.9   4.3
 11000   3.6  38.5  290   9  4   5.8   3.2 |   3.9  39.0  230   1  1   5.7   3.1
 10500   4.4  39.9  285   8  4   6.8   3.7 |   4.7  40.5  175   1  1   6.6   3.6
 10250   4.8  40.6  285   8  4   2.5   1.3 |   5.1  41.2  160   2  1   2.6   1.5
 10000   4.9  40.8  280   7  4   2.1   1.2 |   5.2  41.4  155   2  1   1.7   0.9
  9750   5.3  41.5  275   7  4   6.2   3.4 |   5.5  41.9  155   2  1   4.9   2.7
  9500   5.6  42.1  265   8  4   5.3   2.9 |   5.8  42.4  155   2  1   4.4   2.4
  9250   6.0  42.8  255   8  4   3.2   1.8 |   6.0  42.8  160   3  1   1.4   0.8
  9000   6.1  43.0  250   8  4   0.1   0.1 |   5.9  42.6  160   3  2  -2.0  -1.1
  8750   6.0  42.8  240   9  4  -1.1  -0.6 |   5.7  42.3  155   4  2  -2.4  -1.3
  8500   5.8  42.4  235   9  5  -1.7  -0.9 |   5.4  41.7  150   4  2  -1.6  -0.9
  8250   5.7  42.3  230   9  5  -1.3  -0.7 |   5.4  41.7  140   4  2   1.7   0.9
  8000   5.6  42.1  225   9  5  -1.2  -0.7 |   5.5  41.9  125   4  2   3.8   2.1
  7750   5.4  41.7  215   9  4  -0.7  -0.4 |   5.8  42.4  115   4  2   5.3   2.9
  7500   5.4  41.7  210   8  4  -0.5  -0.3 |   6.2  43.2  110   4  2   8.4   4.6
  7250   5.3  41.5  210   6  3  -0.6  -0.3 |   6.9  44.4  110   4  2  10.1   5.5
  7000   5.2  41.4  205   5  3  -1.3  -0.7 |   7.6  45.7  110   3  2  10.0   5.5
  6750   5.2  41.4  195   3  2   2.2   1.2 |   8.4  47.1  105   3  2   9.7   5.3
  6500   5.6  42.1  180   3  2   7.5   4.1 |   9.1  48.4  105   3  2  10.2   5.6
  6250   6.1  43.0  165   2  1   8.2   4.5 |   9.9  49.8  100   3  1  11.4   6.3
  6000   6.7  44.1  150   2  1   7.8   4.3 |  10.7  51.3  100   3  1   9.2   5.1
  5750   7.4  45.3  130   2  1  12.2   6.7 |  11.5  52.7  095   2  1  13.9   7.6
  5500   8.6  47.5  130   2  1  20.1  11.0 |  13.0  55.4  100   2  1  27.7  15.2

           05/21/2015 at 1500 MDT          |       05/21/2015 at 1800 MDT
                                           |
K index... +18.0  LI... +270.3             | K index... +23.5  LI... +272.0
CAPE... +246.4  CIN... -54.6               | CAPE... +202.6  CIN... -0.6
                                           |
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 -59.8 -75.6  255  35 18  -0.2  -0.1 | -59.0 -74.2  255  35 18   1.1   0.6
 45000 -60.1 -76.2  260  57 30  -0.3  -0.2 | -57.6 -71.7  255  56 29  -2.7  -1.5
 40000 -60.6 -77.1  245  90 46  -0.3  -0.2 | -61.2 -78.2  235  82 42  -2.2  -1.2
 38000 -57.7 -71.9  245  86 44   6.3   3.4 | -58.3 -72.9  235  73 37   7.0   3.8
 36000 -53.9 -65.0  245  78 40   6.3   3.4 | -54.1 -65.4  235  57 29   7.0   3.8
 34000 -49.8 -57.6  240  68 35   8.0   4.4 | -49.6 -57.3  240  46 24   8.5   4.7
 32000 -44.9 -48.8  245  54 28   8.0   4.4 | -44.5 -48.1  245  41 21   8.5   4.7
 30000 -40.1 -40.2  250  44 22   8.2   4.5 | -39.4 -38.9  250  36 19   8.5   4.7
 29000 -37.6 -35.7  250  40 21   8.2   4.5 | -36.2 -33.2  250  33 17   8.5   4.7
 28000 -34.6 -30.3  255  36 19   8.2   4.5 | -33.7 -28.7  250  30 15   8.5   4.7
 27000 -32.2 -26.0  255  33 17   7.7   4.2 | -31.2 -24.2  250  28 14   7.7   4.2
 26000 -29.9 -21.8  255  29 15   7.7   4.2 | -29.0 -20.2  250  26 13   7.7   4.2
 25000 -27.6 -17.7  260  25 13   7.7   4.3 | -26.7 -16.1  250  25 13   7.7   4.2
 24000 -25.4 -13.7  260  23 12   6.7   3.7 | -24.5 -12.1  250  24 12   7.2   3.9
 23000 -23.4 -10.1  255  24 12   6.8   3.7 | -22.3  -8.1  245  25 13   7.2   4.0
 22000 -21.4  -6.5  250  25 13   6.8   3.7 | -20.2  -4.4  240  27 14   7.3   4.0
 21000 -19.5  -3.1  245  25 13   5.9   3.2 | -18.1  -0.6  235  28 14   6.9   3.8
 20000 -17.8  -0.0  235  26 14   5.9   3.2 | -16.1   3.0  225  28 15   6.9   3.8
 19500 -16.9   1.6  230  27 14   5.9   3.3 | -15.1   4.8  220  29 15   6.9   3.8
 19000 -16.0   3.2  225  28 14   5.9   3.3 | -14.1   6.6  215  29 15   7.2   3.9
 18500 -15.1   4.8  220  28 14   6.8   3.7 | -13.2   8.2  210  29 15   4.8   2.6
 18000 -14.1   6.6  220  27 14   6.8   3.7 | -12.5   9.5  205  28 14   5.1   2.8
 17500 -13.1   8.4  215  27 14   7.4   4.0 | -11.7  10.9  195  27 14   5.5   3.0
 17000 -12.0  10.4  210  24 12   7.6   4.2 | -10.8  12.6  190  27 14   5.9   3.3
 16500 -10.9  12.4  205  22 11   7.6   4.2 | -10.0  14.0  185  26 13   6.0   3.3
 16000  -9.8  14.4  200  20 10   7.2   3.9 |  -9.1  15.6  180  26 13   6.1   3.3
 15500  -8.7  16.3  190  18  9   7.0   3.8 |  -8.2  17.2  175  26 13   6.0   3.3
 15000  -6.8  19.8  180  15  8   9.4   5.2 |  -6.8  19.8  170  25 13   6.8   3.8
 14500  -5.3  22.5  170  14  7   9.4   5.2 |  -5.8  21.6  170  25 13   6.8   3.7
 14000  -3.9  25.0  170  13  7   9.3   5.1 |  -4.7  23.5  165  24 12   7.9   4.3
 13500  -2.5  27.5  170  12  6   9.3   5.1 |  -3.5  25.7  160  23 12   7.9   4.3
 13000  -1.1  30.0  170  12  6   9.7   5.3 |  -2.4  27.7  160  21 11   7.3   4.0
 12500   0.3  32.5  170  11  6   9.9   5.4 |  -1.3  29.7  155  18  9   7.5   4.1
 12000   1.7  35.1  165  11  5   8.1   4.5 |  -0.3  31.5  155  16  8   6.1   3.4
 11500   2.9  37.2  160  10  5   8.6   4.7 |   0.6  33.1  155  13  7   6.2   3.4
 11000   3.9  39.0  160   9  5   5.1   2.8 |   1.4  34.5  150  11  6   5.1   2.8
 10500   4.7  40.5  155   8  4   5.9   3.2 |   2.1  35.8  140   8  4   5.4   3.0
 10250   5.0  41.0  155   7  4   3.0   1.6 |   2.4  36.3  130   7  3   3.5   1.9
 10000   5.0  41.0  150   7  4  -0.2  -0.1 |   2.6  36.7  130   6  3   5.1   2.8
  9750   5.0  41.0  145   6  3   0.6   0.3 |   3.1  37.6  125   6  3   8.2   4.5
  9500   4.9  40.8  135   5  3   0.5   0.3 |   3.7  38.7  125   5  3   7.5   4.1
  9250   4.9  40.8  125   4  2   2.2   1.2 |   4.2  39.6  120   5  2   7.5   4.1
  9000   5.1  41.2  110   4  2   5.9   3.2 |   4.7  40.5  120   5  2   8.6   4.7
  8750   5.5  41.9  095   4  2   7.5   4.1 |   5.4  41.7  125   5  3   9.8   5.4
  8500   6.0  42.8  085   4  2   7.7   4.2 |   6.0  42.8  130   5  3   9.7   5.3
  8250   6.6  43.9  075   4  2   9.0   4.9 |   6.7  44.1  130   5  3  10.6   5.8
  8000   7.2  45.0  070   3  2   9.7   5.3 |   7.5  45.5  130   6  3  10.8   5.9
  7750   8.0  46.4  070   3  2   9.8   5.4 |   8.3  46.9  130   6  3  10.0   5.5
  7500   8.7  47.7  065   3  2  10.1   5.5 |   9.0  48.2  130   6  3   9.9   5.4
  7250   9.4  48.9  065   3  2  10.2   5.6 |   9.8  49.6  130   5  3  10.0   5.5
  7000  10.2  50.4  065   3  2  10.2   5.6 |  10.5  50.9  130   5  3  10.0   5.5
  6750  11.0  51.8  060   3  2   9.9   5.4 |  11.2  52.2  130   5  3   9.8   5.4
  6500  11.7  53.1  060   3  2  10.2   5.6 |  12.0  53.6  130   5  3   9.9   5.4
  6250  12.5  54.5  060   3  2  11.1   6.1 |  12.7  54.9  130   5  3  10.2   5.6
  6000  13.3  55.9  055   3  1   9.8   5.4 |  13.5  56.3  130   5  3   9.9   5.5
  5750  14.1  57.4  055   3  1  13.1   7.2 |  14.2  57.6  130   5  3  10.2   5.6
  5500  15.4  59.7  055   3  1  23.1  12.7 |  14.9  58.8  130   5  2  11.5   6.3
________________________________________________________________________________

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.

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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