Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 301234
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0634 MDT Monday, May 30, 2016

This forecast is for Monday, May 30, 2016:

If the trigger temperature of 72.3 F/22.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1156 ft/min (5.9 m/s)
   Maximum height of thermals.................. 17535 ft MSL (12250 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ 1330 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10162 ft MSL (4876 ft AGL)
Thermal soaring outlook for Tuesday 05/31...... Poor

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....................... 20083 ft MSL (14798 ft AGL)
Wave soaring outlook for Tuesday 05/31......... Poor

Remarks...

Sunrise/Sunset.................... 05:34:16 / 20:19:49 MDT
Total possible sunshine........... 14 hr 45 min 33 sec (885 min 33 sec)
Altitude of sun at 12:57:14 MDT... 72.12 degrees

Upper air data from rawinsonde observation taken on 05/30/2016 at 0600 MDT

Freezing level.................. 13552 ft MSL (8267 ft AGL)
Convective condensation level... 15713 ft MSL (10428 ft AGL)
Lifted condensation level....... 15971 ft MSL (10685 ft AGL)
Lifted index.................... -3.2
K index......................... +12.9

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  -57.2 -71.0   245   21   11   3.6   2.0  102.0 215.6    43.7      M    M
 45000  -59.2 -74.6   250   37   19 -16.7  -9.2   74.1 165.3    29.6      M    M
 40000  -61.3 -78.3   235   49   25   7.4   4.1   47.7 117.8    14.3      M    M
 38000  -58.0 -72.4   235   49   25   5.3   2.9   43.8 110.9    12.0      M    M
 36000  -53.9 -65.0   235   43   22   7.4   4.1   41.2 106.2    10.6      M    M
 34000  -48.9 -56.0   235   38   20   7.6   4.2   39.0 102.2     9.3      M    M
 32000  -44.3 -47.7   240   35   18   7.8   4.3   37.2  99.0     8.2      M    M
 30000  -39.9 -39.8   250   31   16   7.0   3.8   35.4  95.8     7.0      M    M
 29000  -37.4 -35.3   255   31   16   9.1   5.0   34.8  94.6     6.6      M    M
 28000  -34.7 -30.5   260   32   16   9.2   5.0   34.6  94.2     6.6      M    M
 27000  -32.3 -26.1   255   29   15   1.9   1.0   33.8  92.8     6.0      M    M
 26000  -30.4 -22.7   245   27   14   7.1   3.9   32.5  90.5     5.1      M    M
 25000  -28.5 -19.3   235   26   13   6.5   3.6   31.3  88.3     4.1      M    M
 24000  -26.0 -14.8   230   22   11   7.7   4.2   30.7  87.3     3.7      M    M
 23000  -23.6 -10.5   245   18    9   6.3   3.4   30.0  86.1     3.2      M    M
 22000  -21.6  -6.9   250   19   10   8.1   4.4   29.0  84.3     2.3      M    M
 21000  -19.0  -2.2   260   21   11   7.3   4.0   28.6  83.5     2.0      M    M
 20000  -16.9   1.6   265   23   12   7.0   3.9   27.7  81.8     1.2      M    M
 19500  -15.8   3.6   265   23   12   7.4   4.1   27.2  81.0     0.8      M    M
 19000  -14.4   6.1   270   23   12   8.3   4.5   27.1  80.8     0.8      M    M
 18500  -13.5   7.7   270   23   12   8.5   4.6   26.6  79.8     0.2      M    M
 18000  -12.1  10.2   270   23   12   9.2   5.0   26.4  79.6     0.1      M    M
 17500  -10.7  12.7   270   23   12   9.2   5.1   26.3  79.4     0.0      M    M
 17000   -8.7  16.3   270   22   11   9.2   5.0   26.2  79.2    -0.1   1081  5.5
 16500   -7.3  18.9   270   22   11   9.0   4.9   26.2  79.1    -0.1   1024  5.2
 16000   -6.0  21.2   270   22   11   8.6   4.7   26.0  78.8    -0.3    971  4.9
 15500   -4.7  23.5   270   20   10   8.6   4.7   25.8  78.4    -0.5    918  4.7
 15000   -3.5  25.7   270   18    9   8.6   4.7   25.6  78.0    -0.7    866  4.4
 14500   -2.2  28.0   275   16    8   8.6   4.7   25.4  77.7    -0.9    813  4.1
 14000   -0.9  30.4   275   15    8   8.6   4.7   25.3  77.5    -1.1    760  3.9
 13500    0.3  32.5   280   13    7   8.7   4.8   25.1  77.1    -1.3    707  3.6
 13000    1.6  34.9   280   12    6   8.8   4.8   24.9  76.8    -1.5    654  3.3
 12500    2.8  37.0   270   13    7   7.7   4.2   24.6  76.3    -1.8    603  3.1
 12000    4.0  39.2   265   14    7   8.1   4.5   24.3  75.7    -2.0    552  2.8
 11500    5.2  41.4   255   13    6   8.4   4.6   24.1  75.3    -2.3    501  2.5
 11000    6.5  43.7   245   12    6   8.5   4.7   23.9  74.9    -2.6    449  2.3
 10500    7.7  45.9   235   11    6   8.6   4.7   23.7  74.6    -2.8    398  2.0
 10250    8.3  46.9   230   11    6   8.2   4.5   23.6  74.4    -3.0    372  1.9
 10000    8.9  48.0   225   11    5   8.0   4.4   23.4  74.2    -3.1    348  1.8
  9750    9.4  48.9   220   10    5   8.0   4.4   23.3  74.0    -3.3    323  1.6
  9500   10.0  50.0   215   10    5   8.0   4.4   23.2  73.7    -3.4    298  1.5
  9250   10.6  51.1   210   10    5   8.1   4.4   23.1  73.5    -3.6    273  1.4
  9000   11.2  52.2   205   10    5   8.1   4.4   22.9  73.3    -3.7    248  1.3
  8750   11.8  53.2   205   11    6   8.0   4.4   22.8  73.0    -3.9    223  1.1
  8500   12.4  54.3   205   13    6   8.4   4.6   22.7  72.8    -4.1    199  1.0
  8250   12.9  55.2   205   14    7   6.8   3.7   22.5  72.6    -4.2    174  0.9
  8000   13.3  55.9   205   15    8   4.9   2.7   22.2  72.0    -4.6    155  0.8
  7750   13.7  56.7   205   15    8   5.1   2.8   21.9  71.3    -4.9    136  0.7
  7500   14.1  57.4   205   15    8   5.0   2.8   21.5  70.7    -5.3    118  0.6
  7250   14.4  57.9   200   15    8   5.3   2.9   21.1  70.1    -5.7     99  0.5
  7000   14.8  58.6   200   15    8   4.4   2.4   20.8  69.4    -6.1     81  0.4
  6750   15.2  59.4   205   16    8   7.5   4.1   20.4  68.8    -6.4     63  0.3
  6500   15.5  59.9   210   16    8  -3.8  -2.1   20.1  68.2    -6.8     44  0.2
  6250   14.6  58.3   215   17    9 -12.4  -6.8   18.5  65.2    -8.5     64  0.3
  6000   14.0  57.2   220   18    9  -4.8  -2.7   17.1  62.9    -9.8     74  0.4
  5750   13.4  56.1   220   13    7 -14.1  -7.7   15.8  60.5   -11.2     85  0.4
  5500   11.6  52.9   215    8    4 -29.6 -16.2   13.4  56.1   -13.7    132  0.7

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

           05/30/2016 at 0900 MDT          |       05/30/2016 at 1200 MDT
                                           |
K index... +16.7  LI... -1.2               | K index... +11.4  LI... -3.2
CAPE... +157.2  CIN... -103.5              | CAPE... +663.6  CIN... -29.9
                                           |
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 -57.2 -71.0  255  27 14  -0.1  -0.0 | -57.1 -70.8  255  26 14   0.3   0.1
 45000 -57.5 -71.5  255  36 19  -1.7  -0.9 | -56.9 -70.4  255  34 17  -1.4  -0.8
 40000 -60.0 -76.0  245  52 27  -1.5  -0.8 | -59.1 -74.4  245  52 27  -1.2  -0.7
 38000 -57.9 -72.2  240  50 26   5.5   3.0 | -57.0 -70.6  240  52 27   5.3   2.9
 36000 -54.2 -65.6  240  45 23   5.5   3.0 | -53.4 -64.1  240  50 25   5.3   2.9
 34000 -50.1 -58.2  235  40 20   7.9   4.4 | -49.8 -57.6  240  45 23   6.7   3.6
 32000 -45.4 -49.7  235  33 17   7.9   4.4 | -45.8 -50.4  240  39 20   6.7   3.7
 30000 -40.5 -40.9  240  27 14   8.2   4.5 | -41.3 -42.3  240  34 18   8.3   4.6
 29000 -38.0 -36.4  240  25 13   8.2   4.5 | -38.8 -37.8  245  33 17   8.4   4.6
 28000 -35.6 -32.1  240  23 12   8.2   4.5 | -36.3 -33.3  245  31 16   8.4   4.6
 27000 -33.2 -27.8  240  21 11   7.3   4.0 | -33.7 -28.7  245  29 15   8.6   4.7
 26000 -31.1 -24.0  240  19 10   7.3   4.0 | -31.1 -24.0  245  27 14   8.6   4.7
 25000 -28.9 -20.0  240  17  9   7.3   4.0 | -28.5 -19.3  245  25 13   8.6   4.7
 24000 -26.7 -16.1  240  16  8   7.7   4.2 | -26.1 -15.0  240  23 12   6.7   3.7
 23000 -24.4 -11.9  245  16  8   7.7   4.2 | -24.1 -11.4  240  23 12   6.9   3.8
 22000 -22.1  -7.8  250  16  8   7.8   4.3 | -22.0  -7.6  240  22 11   7.0   3.8
 21000 -19.7  -3.5  255  16  8   8.1   4.4 | -19.8  -3.6  240  22 11   8.3   4.6
 20000 -17.3   0.9  260  17  9   8.1   4.5 | -17.3   0.9  245  21 11   8.4   4.6
 19500 -16.1   3.0  260  18  9   8.1   4.5 | -16.1   3.0  250  21 11   8.4   4.6
 19000 -14.9   5.2  265  18 10   8.2   4.5 | -14.8   5.4  250  21 11   8.6   4.7
 18500 -13.6   7.5  265  19 10   8.8   4.8 | -13.5   7.7  255  21 11   9.6   5.2
 18000 -11.6  11.1  265  19 10   8.8   4.8 | -11.3  11.7  260  21 11   9.4   5.1
 17500 -10.3  13.5  260  19 10   8.8   4.8 | -10.0  14.0  260  21 11   8.8   4.8
 17000  -9.0  15.8  260  18 10   8.8   4.8 |  -8.7  16.3  265  21 11   8.8   4.9
 16500  -7.7  18.1  260  18  9   8.7   4.8 |  -7.3  18.9  265  21 11   9.0   5.0
 16000  -6.4  20.5  260  17  9   8.7   4.8 |  -6.0  21.2  265  20 10   9.1   5.0
 15500  -5.1  22.8  260  16  8   8.9   4.9 |  -4.6  23.7  270  19 10   9.1   5.0
 15000  -3.8  25.2  260  15  8   9.0   5.0 |  -3.2  26.2  270  18  9   9.2   5.0
 14500  -2.5  27.5  260  14  7   9.2   5.0 |  -1.9  28.6  270  17  9   9.0   5.0
 14000  -1.1  30.0  260  14  7   9.5   5.2 |  -0.6  30.9  270  16  8   8.6   4.7
 13500   0.3  32.5  260  14  7   9.4   5.2 |   0.7  33.3  275  15  7   8.6   4.7
 13000   1.7  35.1  260  13  7   9.0   4.9 |   2.0  35.6  275  13  7   8.5   4.7
 12500   3.0  37.4  260  13  7   9.0   4.9 |   3.3  37.9  275  12  6   8.5   4.7
 12000   4.3  39.7  260  13  7   9.3   5.1 |   4.5  40.1  280  11  6   8.6   4.7
 11500   5.7  42.3  260  12  6   9.3   5.1 |   5.8  42.4  280   9  5   8.6   4.7
 11000   7.1  44.8  260  12  6   9.2   5.1 |   7.1  44.8  285   8  4   8.7   4.8
 10500   8.4  47.1  260  11  6   9.8   5.4 |   8.4  47.1  290   8  4   9.2   5.1
 10250   9.1  48.4  260  11  6   5.6   3.1 |   9.0  48.2  290   7  4   6.5   3.5
 10000   9.4  48.9  260  11  6   6.5   3.6 |   9.4  48.9  290   7  4   7.4   4.1
  9750  10.1  50.2  260  11  6  11.0   6.0 |  10.2  50.4  295   6  3  10.8   5.9
  9500  10.8  51.4  265  10  5  10.0   5.5 |  10.9  51.6  300   6  3  10.3   5.6
  9250  11.6  52.9  265  10  5   8.3   4.6 |  11.6  52.9  300   5  3   7.8   4.3
  9000  12.1  53.8  260  10  5   7.1   3.9 |  12.1  53.8  310   5  3   7.3   4.0
  8750  12.6  54.7  260   9  5   8.0   4.4 |  12.7  54.9  315   5  2   9.4   5.1
  8500  13.2  55.8  260   9  4   7.6   4.2 |  13.4  56.1  325   4  2   8.9   4.9
  8250  13.7  56.7  260   8  4   7.2   4.0 |  14.0  57.2  335   4  2   9.8   5.4
  8000  14.2  57.6  260   7  4   6.7   3.7 |  14.6  58.3  350   4  2  10.0   5.5
  7750  14.7  58.5  260   6  3   6.3   3.4 |  15.3  59.5  355   4  2   9.3   5.1
  7500  15.1  59.2  260   6  3   6.2   3.4 |  15.9  60.6  005   3  2   9.6   5.3
  7250  15.6  60.1  255   5  3   6.5   3.6 |  16.6  61.9  010   3  2  10.3   5.6
  7000  16.0  60.8  250   4  2   6.3   3.4 |  17.4  63.3  010   3  2  10.3   5.7
  6750  16.5  61.7  240   4  2   5.6   3.1 |  18.1  64.6  010   3  2   9.1   5.0
  6500  16.8  62.2  225   3  2   2.3   1.2 |  18.8  65.8  005   3  2   9.9   5.4
  6250  16.8  62.2  235   2  1   0.6   0.3 |  19.6  67.3  005   3  2  11.6   6.4
  6000  16.8  62.2  250   2  1  -0.1  -0.1 |  20.5  68.9  005   3  2  10.3   5.7
  5750  16.7  62.1  275   2  1   2.0   1.1 |  21.3  70.3  005   3  2  13.1   7.2
  5500  17.2  63.0  300   2  1  13.9   7.6 |  22.6  72.7  005   3  2  23.4  12.9

           05/30/2016 at 1500 MDT          |       05/30/2016 at 1800 MDT
                                           |
K index... +25.6  LI... -0.7               | K index... +24.1  LI... -1.0
CAPE... +130.2  CIN... -44.7               | CAPE... +79.1  CIN... -80.1
                                           |
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 -57.0 -70.6  255  28 14   0.4   0.2 | -57.0 -70.6  255  26 13  -0.3  -0.1
 45000 -56.7 -70.1  255  32 16  -1.7  -1.0 | -57.5 -71.5  250  28 14  -1.0  -0.6
 40000 -59.4 -74.9  250  51 26  -1.6  -0.9 | -59.1 -74.4  250  41 21  -1.3  -0.7
 38000 -57.7 -71.9  250  50 26   4.5   2.5 | -57.2 -71.0  250  40 21   4.0   2.2
 36000 -54.6 -66.3  255  45 23   4.5   2.5 | -54.8 -66.6  245  38 20   4.1   2.2
 34000 -50.7 -59.3  255  39 20   8.5   4.7 | -51.0 -59.8  240  34 17   9.1   5.0
 32000 -45.6 -50.1  255  32 17   8.5   4.7 | -45.5 -49.9  240  26 14   9.1   5.0
 30000 -40.2 -40.4  250  28 15   9.4   5.2 | -40.0 -40.0  235  22 11   9.3   5.1
 29000 -37.4 -35.3  250  27 14   9.4   5.2 | -36.5 -33.7  235  21 11   9.3   5.1
 28000 -34.6 -30.3  250  27 14   9.4   5.1 | -33.7 -28.7  235  20 10   9.4   5.2
 27000 -31.9 -25.4  250  25 13   8.2   4.5 | -31.2 -24.2  235  20 10   8.1   4.5
 26000 -29.5 -21.1  250  24 12   8.2   4.5 | -28.8 -19.8  240  19 10   8.1   4.5
 25000 -27.1 -16.8  245  23 12   8.2   4.5 | -26.4 -15.5  240  19 10   8.1   4.5
 24000 -24.7 -12.5  245  22 11   7.5   4.1 | -24.0 -11.2  245  19 10   7.5   4.1
 23000 -22.5  -8.5  245  20 11   7.5   4.1 | -21.8  -7.2  250  18 10   7.5   4.1
 22000 -20.2  -4.4  240  19 10   7.5   4.1 | -19.6  -3.3  260  19 10   7.5   4.1
 21000 -18.1  -0.6  235  19 10   7.1   3.9 | -17.5   0.5  265  19 10   6.8   3.7
 20000 -16.0   3.2  230  19 10   7.1   3.9 | -15.5   4.1  270  20 10   6.8   3.7
 19500 -14.9   5.2  230  19 10   7.1   3.9 | -14.5   5.9  270  20 10   6.8   3.7
 19000 -13.9   7.0  230  19 10   7.1   3.9 | -13.5   7.7  275  20 10   6.8   3.7
 18500 -12.3   9.9  225  18  9   7.0   3.9 | -12.5   9.5  275  20 10   6.9   3.8
 18000 -11.3  11.7  225  17  9   7.0   3.9 | -11.5  11.3  280  20 10   6.9   3.8
 17500 -10.3  13.5  220  16  8   7.0   3.8 | -10.5  13.1  280  20 10   7.3   4.0
 17000  -9.2  15.4  215  16  8   7.0   3.9 |  -9.4  15.1  280  19 10   7.3   4.0
 16500  -8.2  17.2  215  16  8   7.1   3.9 |  -8.3  17.1  285  19 10   7.4   4.1
 16000  -7.2  19.0  215  16  8   7.1   3.9 |  -7.2  19.0  285  18  9   7.6   4.2
 15500  -6.1  21.0  210  15  8   7.3   4.0 |  -6.1  21.0  285  17  9   7.6   4.1
 15000  -5.0  23.0  210  13  7   7.5   4.1 |  -4.4  24.1  285  16  8   7.9   4.3
 14500  -3.9  25.0  215  12  6   7.9   4.3 |  -3.3  26.1  285  14  7   8.0   4.4
 14000  -2.6  27.3  215  10  5   9.6   5.2 |  -2.1  28.2  280  13  7   8.3   4.5
 13500  -1.2  29.8  220   8  4   9.5   5.2 |  -0.9  30.4  275  12  6   8.3   4.5
 13000   0.3  32.5  225   6  3  10.0   5.5 |   0.4  32.7  270  11  6   8.5   4.7
 12500   1.8  35.2  235   6  3   9.9   5.4 |   1.6  34.9  260  11  5   8.5   4.7
 12000   3.3  37.9  245   5  3  10.0   5.5 |   2.9  37.2  250  11  5   8.6   4.7
 11500   4.8  40.6  255   5  2  10.1   5.5 |   4.1  39.4  245  11  6   8.5   4.7
 11000   6.2  43.2  265   4  2   9.4   5.2 |   5.4  41.7  240  11  6   9.1   5.0
 10500   7.6  45.7  280   4  2  10.2   5.6 |   6.7  44.1  240  11  6   9.9   5.4
 10250   8.3  46.9  285   5  2   6.7   3.7 |   7.4  45.3  240  11  6   5.5   3.0
 10000   8.7  47.7  285   5  2   7.9   4.3 |   7.7  45.9  240  11  6   6.4   3.5
  9750   9.6  49.3  290   5  3  12.1   6.7 |   8.4  47.1  240  11  6  11.3   6.2
  9500  10.4  50.7  290   5  3  11.3   6.2 |   9.2  48.6  245  11  6  10.2   5.6
  9250  11.2  52.2  295   5  3   9.6   5.3 |   9.9  49.8  245  11  6   8.4   4.6
  9000  11.9  53.4  300   5  3   9.2   5.0 |  10.5  50.9  245  11  6   7.9   4.3
  8750  12.6  54.7  300   6  3  10.8   5.9 |  11.1  52.0  250  11  6   9.5   5.2
  8500  13.4  56.1  305   6  3  10.3   5.7 |  11.8  53.2  250  12  6   9.0   4.9
  8250  14.2  57.6  305   6  3  10.4   5.7 |  12.5  54.5  255  12  6   8.4   4.6
  8000  15.0  59.0  305   6  3  10.1   5.5 |  13.1  55.6  255  12  6   8.0   4.4
  7750  15.7  60.3  305   7  3   9.7   5.3 |  13.7  56.7  260  12  6   8.3   4.6
  7500  16.4  61.5  310   7  4   9.9   5.4 |  14.2  57.6  265  12  6   7.9   4.3
  7250  17.2  63.0  310   7  4  10.3   5.6 |  14.8  58.6  265  12  6   7.2   3.9
  7000  18.0  64.4  310   7  4  10.2   5.6 |  15.3  59.5  270  12  6   7.0   3.9
  6750  18.7  65.7  310   7  4   8.9   4.9 |  15.8  60.4  270  12  6   7.3   4.0
  6500  19.4  66.9  310   8  4   9.6   5.3 |  16.3  61.3  275  12  6   7.2   3.9
  6250  20.2  68.4  310   8  4  11.2   6.1 |  16.9  62.4  270  11  6   7.2   3.9
  6000  20.9  69.6  310   8  4  10.4   5.7 |  17.4  63.3  270  11  6   6.8   3.7
  5750  21.7  71.1  310   8  4  11.4   6.2 |  17.9  64.2  270  11  5   7.9   4.3
  5500  22.7  72.9  315   8  4  15.5   8.5 |  18.5  65.3  270   9  5  11.8   6.5
________________________________________________________________________________

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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