Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 280102
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1902 MDT Wednesday, May 27, 2015

This forecast is for Thursday, May 28, 2015:

If the trigger temperature of 69.0 F/20.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 577 ft/min (2.9 m/s)
   Maximum height of thermals.................. 14283 ft MSL (8976 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 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................. 10090 ft MSL (4783 ft AGL)
Thermal soaring outlook for Friday 05/29....... Excellent

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 NVA
Potential height of wave....................... 15151 ft MSL (9844 ft AGL)
Wave soaring outlook for Friday 05/29.......... Poor

Remarks...

Sunrise/Sunset.................... 05:35:38 / 20:17:41 MDT
Total possible sunshine........... 14 hr 42 min 3 sec (882 min 3 sec)
Altitude of sun at 12:56:51 MDT... 71.71 degrees

Upper air data from numerical model forecast valid on 05/28/2015 at 0600 MDT

Freezing level.................. 12905 ft MSL (7598 ft AGL)
Convective condensation level... 14491 ft MSL (9184 ft AGL)
Lifted condensation level....... 14504 ft MSL (9197 ft AGL)
Lifted index.................... -1.5
K index......................... +20.9

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  -58.9 -74.0   235   15    8  -1.1  -0.6      M     M       M      M    M
 45000  -60.5 -76.9   225   30   16  -0.5  -0.3      M     M       M      M    M
 40000  -61.2 -78.2   200   43   22  -0.5  -0.3      M     M       M      M    M
 38000  -58.1 -72.6   200   43   22   6.7   3.7      M     M       M      M    M
 36000  -54.1 -65.4   205   40   21   6.7   3.7      M     M       M      M    M
 34000  -49.6 -57.3   210   38   19   8.6   4.7      M     M       M      M    M
 32000  -43.9 -47.0   215   36   19   8.6   4.7      M     M       M      M    M
 30000  -38.7 -37.7   220   36   18   8.6   4.7   36.7  98.0     9.7      M    M
 29000  -36.1 -33.0   225   35   18   8.6   4.7   36.2  97.2     9.4      M    M
 28000  -33.5 -28.3   225   35   18   8.6   4.7   35.9  96.6     9.3      M    M
 27000  -31.1 -24.0   230   33   17   7.6   4.2   35.2  95.4     8.9      M    M
 26000  -28.9 -20.0   230   31   16   7.5   4.1   34.3  93.8     8.2      M    M
 25000  -26.6 -15.9   235   28   15   7.5   4.1   33.6  92.4     7.7      M    M
 24000  -24.5 -12.1   235   26   13   6.6   3.6   32.7  90.8     7.0      M    M
 23000  -22.5  -8.5   240   23   12   6.7   3.7   31.5  88.7     6.1      M    M
 22000  -20.5  -4.9   240   20   10   6.7   3.7   30.4  86.7     5.3      M    M
 21000  -18.5  -1.3   245   18    9   6.7   3.7   29.3  84.8     4.4      M    M
 20000  -16.6   2.1   255   17    9   6.7   3.7   28.2  82.8     3.5      M    M
 19500  -15.6   3.9   260   16    8   6.8   3.7   27.7  81.8     3.0      M    M
 19000  -14.6   5.7   265   16    8   6.8   3.7   27.2  81.0     2.6      M    M
 18500  -13.6   7.5   265   16    8   7.2   4.0   26.8  80.2     2.2      M    M
 18000  -12.5   9.5   265   15    8   7.2   3.9   26.3  79.4     1.8      M    M
 17500  -11.4  11.5   270   15    8   8.5   4.7   26.0  78.7     1.5      M    M
 17000  -10.0  14.0   270   16    8   8.9   4.9   25.8  78.4     1.4      M    M
 16500   -8.1  17.4   270   17    9   8.7   4.8   25.6  78.1     1.2      M    M
 16000   -6.8  19.8   275   18    9   8.7   4.8   25.4  77.7     1.0      M    M
 15500   -5.5  22.1   275   19   10   8.2   4.5   25.3  77.5     0.8      M    M
 15000   -4.4  24.1   275   19   10   7.6   4.2   24.9  76.8     0.5      M    M
 14500   -3.3  26.1   275   20   10   7.6   4.2   24.5  76.1     0.1      M    M
 14000   -2.2  28.0   275   19   10   7.3   4.0   24.1  75.4    -0.3    743  3.8
 13500   -1.2  29.8   275   18    9   7.4   4.0   23.7  74.7    -0.7    696  3.5
 13000   -0.1  31.8   275   16    8   7.8   4.3   23.4  74.1    -1.1    649  3.3
 12500    1.0  33.8   270   14    7   7.7   4.2   23.1  73.5    -1.4    601  3.1
 12000    2.2  36.0   265   12    6   8.4   4.6   22.8  73.0    -1.7    551  2.8
 11500    3.4  38.1   260   10    5   8.4   4.6   22.6  72.6    -2.0    499  2.5
 11000    4.6  40.3   255    9    4   7.7   4.2   22.3  72.1    -2.3    449  2.3
 10500    5.7  42.3   250    7    4   8.3   4.6   22.0  71.5    -2.6    401  2.0
 10250    6.3  43.3   250    6    3   5.4   3.0   21.8  71.3    -2.8    376  1.9
 10000    6.6  43.9   250    6    3   6.8   3.7   21.4  70.5    -3.2    359  1.8
  9750    7.4  45.3   250    5    2  10.6   5.8   21.4  70.5    -3.2    330  1.7
  9500    8.1  46.6   250    4    2   9.9   5.4   21.4  70.6    -3.2    300  1.5
  9250    8.8  47.8   255    3    2   7.7   4.2   21.4  70.5    -3.2    272  1.4
  9000    9.3  48.7   270    3    1   7.1   3.9   21.2  70.1    -3.5    250  1.3
  8750    9.9  49.8   290    2    1   8.9   4.9   21.1  69.9    -3.6    224  1.1
  8500   10.5  50.9   310    3    1   8.3   4.5   21.0  69.7    -3.7    198  1.0
  8250   11.1  52.0   325    3    2   7.6   4.2   20.8  69.5    -3.9    173  0.9
  8000   11.7  53.1   335    4    2   6.9   3.8   20.6  69.1    -4.0    149  0.8
  7750   12.2  54.0   340    5    2   6.6   3.6   20.4  68.7    -4.3    126  0.6
  7500   12.6  54.7   345    5    3   6.0   3.3   20.1  68.2    -4.5    105  0.5
  7250   13.1  55.6   350    6    3   5.5   3.0   19.8  67.7    -4.9     85  0.4
  7000   13.5  56.3   350    6    3   5.2   2.9   19.5  67.1    -5.2     66  0.3
  6750   13.8  56.8   350    6    3   4.5   2.5   19.1  66.4    -5.6     47  0.2
  6500   14.0  57.2   350    6    3  -1.4  -0.8   18.6  65.4    -6.1     34  0.2
  6250   13.6  56.5   345    5    3  -6.6  -3.6   17.4  63.4    -7.3     39  0.2
  6000   13.2  55.8   335    4    2  -2.0  -1.1   16.3  61.4    -8.5     44  0.2
  5750   12.9  55.2   325    4    2  -9.8  -5.4   15.4  59.7    -9.5     46  0.2
  5500   11.0  51.8   280    2    1 -40.9 -22.4   12.8  55.1   -12.2     96  0.5

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

           05/28/2015 at 0900 MDT          |       05/28/2015 at 1200 MDT
                                           |
K index... +21.1  LI... +272.3             | K index... +25.0  LI... +270.6
CAPE... +57.2  CIN... -49.2                | CAPE... +517.8  CIN... -27.8
                                           |
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 -58.1 -72.6  230  15  8  -0.1  -0.1 | -58.3 -72.9  240  16  8   0.5   0.3
 45000 -58.5 -73.3  235  28 14  -1.3  -0.7 | -57.7 -71.9  245  25 13  -0.8  -0.4
 40000 -60.5 -76.9  205  34 18  -1.1  -0.6 | -59.0 -74.2  215  28 14  -0.7  -0.4
 38000 -57.9 -72.2  205  35 18   6.2   3.4 | -57.0 -70.6  215  28 14   4.7   2.6
 36000 -54.2 -65.6  210  35 18   6.2   3.4 | -54.2 -65.6  225  27 14   4.7   2.6
 34000 -49.4 -56.9  220  34 17   8.1   4.4 | -50.0 -58.0  230  26 14   8.0   4.4
 32000 -44.6 -48.3  225  32 16   8.1   4.4 | -45.2 -49.4  235  27 14   8.0   4.4
 30000 -39.6 -39.3  230  30 15   8.6   4.7 | -40.2 -40.4  235  26 13   8.7   4.8
 29000 -37.0 -34.6  235  29 15   8.6   4.7 | -37.6 -35.7  235  26 13   8.7   4.8
 28000 -34.4 -29.9  235  28 14   8.6   4.7 | -35.0 -31.0  235  25 13   8.7   4.8
 27000 -32.0 -25.6  235  26 14   8.0   4.4 | -32.5 -26.5  230  25 13   7.7   4.2
 26000 -29.6 -21.3  235  25 13   8.0   4.4 | -30.2 -22.4  230  26 13   7.7   4.2
 25000 -27.2 -17.0  230  23 12   8.0   4.4 | -27.9 -18.2  230  26 13   7.7   4.2
 24000 -25.0 -13.0  230  22 11   6.2   3.4 | -25.6 -14.1  230  26 14   7.5   4.1
 23000 -23.1  -9.6  230  22 11   6.4   3.5 | -23.4 -10.1  235  26 13   7.5   4.1
 22000 -21.2  -6.2  230  21 11   6.4   3.5 | -21.1  -6.0  235  25 13   7.5   4.1
 21000 -19.1  -2.4  230  21 11   7.6   4.1 | -18.9  -2.0  240  24 13   7.5   4.1
 20000 -16.8   1.8  230  20 10   7.6   4.2 | -16.7   1.9  245  24 12   7.5   4.1
 19500 -15.7   3.7  230  19 10   7.6   4.2 | -15.6   3.9  245  24 12   7.6   4.2
 19000 -14.5   5.9  230  18  9   7.7   4.2 | -14.5   5.9  245  24 12   7.6   4.2
 18500 -13.2   8.2  230  18  9   9.0   5.0 | -13.4   7.9  245  24 12   7.4   4.1
 18000 -11.9  10.6  235  18  9   9.0   4.9 | -12.3   9.9  250  24 12   7.4   4.1
 17500 -10.6  12.9  240  18  9   7.8   4.3 | -10.5  13.1  250  24 12   8.3   4.6
 17000  -9.0  15.8  250  18  9   7.5   4.1 |  -9.3  15.3  250  24 12   8.3   4.6
 16500  -7.9  17.8  255  18  9   7.2   4.0 |  -8.1  17.4  250  23 12   8.0   4.4
 16000  -6.9  19.6  260  19 10   7.3   4.0 |  -7.0  19.4  245  22 11   8.0   4.4
 15500  -5.9  21.4  265  19 10   7.4   4.1 |  -5.8  21.6  245  21 11   7.8   4.3
 15000  -4.8  23.4  265  19 10   7.5   4.1 |  -4.7  23.5  245  19 10   7.6   4.2
 14500  -3.7  25.3  265  19 10   7.6   4.2 |  -3.6  25.5  245  17  9   7.7   4.3
 14000  -2.6  27.3  265  18  9   7.7   4.2 |  -2.4  27.7  245  16  8   8.5   4.7
 13500  -1.5  29.3  265  17  9   7.7   4.2 |  -1.2  29.8  240  14  7   8.5   4.7
 13000  -0.4  31.3  260  15  8   8.5   4.7 |   0.1  32.2  240  13  7   8.5   4.7
 12500   0.9  33.6  260  14  7   8.5   4.7 |   1.3  34.3  235  12  6   8.5   4.7
 12000   2.1  35.8  255  12  6   8.0   4.4 |   2.6  36.7  235  11  6   8.8   4.8
 11500   3.2  37.8  245  11  5   8.1   4.4 |   3.9  39.0  235  11  5   8.8   4.8
 11000   4.5  40.1  240  10  5   8.6   4.7 |   5.1  41.2  235  10  5   8.6   4.7
 10500   5.7  42.3  230   9  5   9.3   5.1 |   6.4  43.5  235  10  5   9.4   5.2
 10250   6.3  43.3  225   9  5   5.5   3.0 |   7.0  44.6  235  10  5   5.1   2.8
 10000   6.7  44.1  225   9  4   6.8   3.7 |   7.3  45.1  230   9  5   5.8   3.2
  9750   7.4  45.3  220   8  4  11.3   6.2 |   8.0  46.4  230   9  4  10.7   5.9
  9500   8.2  46.8  215   8  4  10.4   5.7 |   8.7  47.7  225   8  4   9.7   5.3
  9250   8.9  48.0  210   7  4   7.8   4.3 |   9.3  48.7  225   8  4   7.9   4.3
  9000   9.4  48.9  210   6  3   6.7   3.7 |   9.8  49.6  220   7  3   6.9   3.8
  8750  10.0  50.0  215   5  3   8.6   4.7 |  10.4  50.7  220   5  2   8.1   4.4
  8500  10.6  51.1  220   4  2   7.7   4.2 |  10.9  51.6  210   3  2   7.9   4.3
  8250  11.1  52.0  230   3  2   6.0   3.3 |  11.5  52.7  200   1  1   8.2   4.5
  8000  11.5  52.7  255   3  1   5.1   2.8 |  12.1  53.8  000   0  0   9.0   4.9
  7750  11.9  53.4  280   3  1   5.7   3.1 |  12.8  55.0  025   1  0  10.1   5.5
  7500  12.3  54.1  300   3  1   5.7   3.1 |  13.6  56.5  020   1  1  10.2   5.6
  7250  12.8  55.0  310   3  2   5.7   3.2 |  14.3  57.7  020   1  1  10.0   5.5
  7000  13.2  55.8  315   4  2   5.7   3.1 |  15.0  59.0  020   2  1  10.0   5.5
  6750  13.5  56.3  320   4  2   4.4   2.4 |  15.8  60.4  020   2  1   9.4   5.2
  6500  13.8  56.8  320   5  2   4.0   2.2 |  16.5  61.7  015   2  1  10.4   5.7
  6250  14.1  57.4  310   5  2   5.0   2.8 |  17.3  63.1  015   2  1  11.8   6.5
  6000  14.4  57.9  300   5  2   3.5   1.9 |  18.2  64.8  015   2  1  10.4   5.7
  5750  14.7  58.5  290   5  2   7.6   4.2 |  19.0  66.2  010   2  1  13.0   7.1
  5500  15.7  60.3  285   4  2  19.9  10.9 |  20.3  68.5  015   2  1  23.2  12.7

           05/28/2015 at 1500 MDT          |       05/28/2015 at 1800 MDT
                                           |
K index... +26.4  LI... +272.0             | K index... +23.3  LI... +270.0
CAPE... +147.5  CIN... -11.1               | CAPE... +435.4  CIN... -55.1
                                           |
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 -57.7 -71.9  250  13  7   1.0   0.6 | -57.6 -71.7  265  11  6   1.2   0.7
 45000 -56.5 -69.7  250  18  9  -1.2  -0.7 | -56.2 -69.2  255  13  7  -1.4  -0.7
 40000 -58.4 -73.1  235  30 16  -1.1  -0.6 | -58.3 -72.9  260  29 15  -1.2  -0.7
 38000 -56.8 -70.2  230  31 16   4.1   2.2 | -56.3 -69.3  255  32 16   4.9   2.7
 36000 -54.1 -65.4  225  31 16   4.1   2.2 | -53.0 -63.4  255  33 17   5.0   2.7
 34000 -50.3 -58.5  225  31 16   8.5   4.7 | -49.1 -56.4  250  33 17   7.9   4.3
 32000 -45.1 -49.2  225  30 16   8.5   4.7 | -44.3 -47.7  250  33 17   7.9   4.3
 30000 -39.9 -39.8  230  30 16   8.9   4.9 | -39.6 -39.3  245  32 17   7.9   4.4
 29000 -37.2 -35.0  235  31 16   8.9   4.9 | -37.2 -35.0  245  32 17   7.9   4.4
 28000 -34.5 -30.1  240  32 16   8.9   4.9 | -34.8 -30.6  250  32 16   8.0   4.4
 27000 -32.0 -25.6  240  32 16   8.3   4.6 | -32.4 -26.3  250  32 17   8.3   4.6
 26000 -29.5 -21.1  245  31 16   8.3   4.6 | -29.9 -21.8  250  33 17   8.4   4.6
 25000 -27.0 -16.6  250  29 15   8.3   4.6 | -27.4 -17.3  250  33 17   8.4   4.6
 24000 -24.7 -12.5  250  28 14   7.3   4.0 | -24.9 -12.8  255  34 17   7.5   4.1
 23000 -22.5  -8.5  255  26 14   7.4   4.1 | -22.6  -8.7  255  33 17   7.6   4.2
 22000 -20.3  -4.5  255  25 13   7.4   4.1 | -20.4  -4.7  255  33 17   7.6   4.1
 21000 -18.1  -0.6  255  23 12   7.3   4.0 | -18.3  -0.9  260  33 17   6.3   3.5
 20000 -16.0   3.2  255  22 11   7.3   4.0 | -16.4   2.5  260  32 17   6.4   3.5
 19500 -14.9   5.2  255  21 11   7.3   4.0 | -15.5   4.1  260  32 16   6.5   3.6
 19000 -13.8   7.2  255  21 11   7.3   4.0 | -14.6   5.7  265  31 16   6.6   3.6
 18500 -12.8   9.0  255  20 10   6.6   3.6 | -12.8   9.0  265  30 15   8.6   4.7
 18000 -11.3  11.7  255  20 10   6.7   3.7 | -11.5  11.3  265  28 14   8.7   4.8
 17500 -10.3  13.5  255  19 10   6.9   3.8 | -10.3  13.5  265  26 14   8.1   4.5
 17000  -9.3  15.3  255  19 10   6.9   3.8 |  -9.1  15.6  270  25 13   8.1   4.5
 16500  -8.3  17.1  255  18  9   7.0   3.8 |  -7.8  18.0  270  24 12   8.8   4.8
 16000  -7.3  18.9  255  18  9   7.0   3.8 |  -6.5  20.3  275  23 12   8.9   4.9
 15500  -6.3  20.7  260  17  9   6.9   3.8 |  -5.2  22.6  280  22 11   8.9   4.9
 15000  -5.3  22.5  260  16  8   6.9   3.8 |  -3.9  25.0  280  20 11   8.9   4.9
 14500  -4.3  24.3  260  16  8   7.0   3.8 |  -2.6  27.3  285  19 10   8.9   4.9
 14000  -3.2  26.2  255  15  8   7.9   4.3 |  -1.3  29.7  285  18  9   8.8   4.8
 13500  -2.0  28.4  255  15  8   7.9   4.3 |  -0.0  32.0  290  16  8   8.8   4.9
 13000  -0.9  30.4  255  14  7   7.0   3.8 |   1.2  34.2  290  15  8   7.9   4.4
 12500   0.1  32.2  255  13  6   6.8   3.7 |   2.4  36.3  295  13  7   8.0   4.4
 12000   1.4  34.5  255  11  6   9.7   5.3 |   3.6  38.5  300  12  6   8.4   4.6
 11500   2.8  37.0  250  10  5   9.5   5.2 |   4.9  40.8  305  11  6   8.4   4.6
 11000   4.2  39.6  250   9  5   9.4   5.1 |   6.1  43.0  305  10  5   8.3   4.5
 10500   5.5  41.9  245   8  4  10.2   5.6 |   7.3  45.1  300   9  5   8.9   4.9
 10250   6.2  43.2  245   8  4   6.2   3.4 |   7.9  46.2  300   9  5   5.6   3.1
 10000   6.6  43.9  245   7  4   7.2   4.0 |   8.3  46.9  295   9  4   6.1   3.3
  9750   7.4  45.3  245   7  4  11.9   6.5 |   8.9  48.0  290   8  4   9.5   5.2
  9500   8.2  46.8  240   7  3  10.9   6.0 |   9.6  49.3  280   8  4   9.1   5.0
  9250   9.0  48.2  240   6  3   9.6   5.3 |  10.2  50.4  275   8  4   7.3   4.0
  9000   9.6  49.3  240   6  3   9.2   5.0 |  10.6  51.1  265   7  3   6.1   3.4
  8750  10.4  50.7  235   6  3  10.4   5.7 |  11.1  52.0  250   5  3   7.5   4.1
  8500  11.1  52.0  235   6  3  10.1   5.5 |  11.6  52.9  225   5  2   7.2   3.9
  8250  11.9  53.4  235   6  3   9.7   5.3 |  12.1  53.8  205   5  2   8.1   4.4
  8000  12.6  54.7  235   5  3   9.7   5.3 |  12.7  54.9  180   5  3   8.8   4.8
  7750  13.3  55.9  235   5  3  10.3   5.7 |  13.4  56.1  170   5  3   8.7   4.8
  7500  14.1  57.4  235   5  3  10.2   5.6 |  14.0  57.2  160   6  3   9.1   5.0
  7250  14.8  58.6  235   5  3  10.0   5.5 |  14.7  58.5  155   6  3   9.9   5.5
  7000  15.6  60.1  235   5  3   9.9   5.5 |  15.5  59.9  155   6  3  10.2   5.6
  6750  16.3  61.3  235   5  3   9.8   5.4 |  16.2  61.2  150   7  3   9.5   5.2
  6500  17.0  62.6  235   5  3  10.2   5.6 |  16.9  62.4  150   7  3  10.0   5.5
  6250  17.8  64.0  235   5  2  10.8   5.9 |  17.7  63.9  145   7  3  11.1   6.1
  6000  18.6  65.5  235   5  2  10.1   5.6 |  18.5  65.3  145   7  3  10.6   5.8
  5750  19.4  66.9  240   5  2  10.6   5.8 |  19.3  66.7  145   7  3  10.7   5.9
  5500  20.2  68.4  240   5  2  14.5   7.9 |  20.1  68.2  145   7  3  13.0   7.1
________________________________________________________________________________

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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