Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240013
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1813 MDT Sunday, July 23, 2017

This forecast is for Monday, July 24, 2017:

If the trigger temperature of 84.2 F/29.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1153 ft/min (5.9 m/s)
   Maximum height of thermals.................. 18032 ft MSL (12725 ft AGL)

Forecast maximum temperature................... 95.0 F/35.5 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13457 ft MSL (8151 ft AGL)
Thermal soaring outlook for Tuesday 07/25...... 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....................... 40738 ft MSL (35431 ft AGL)
Wave soaring outlook for Tuesday 07/25......... Poor

Remarks...

Sunrise/Sunset.................... 05:51:38 / 20:20:35 MDT
Total possible sunshine........... 14 hr 28 min 56 sec (868 min 56 sec)
Altitude of sun at 13:05:57 MDT... 69.90 degrees

Upper air data from numerical model forecast valid on 07/24/2017 at 0600 MDT

Freezing level.................. 16492 ft MSL (11185 ft AGL)
Convective condensation level... 16548 ft MSL (11241 ft AGL)
Lifted condensation level....... 17226 ft MSL (11919 ft AGL)
Lifted index.................... -2.8
K index......................... +17.7

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  -65.1 -85.2   290   25   13   1.1   0.6      M     M       M      M    M
 45000  -60.7 -77.3   295   45   23   6.1   3.3      M     M       M      M    M
 40000  -51.2 -60.2   295   61   31   7.6   4.2      M     M       M      M    M
 38000  -46.6 -51.9   290   60   31   7.6   4.2      M     M       M      M    M
 36000  -42.1 -43.8   290   60   31   7.6   4.2      M     M       M      M    M
 34000  -37.5 -35.5   290   49   25   7.6   4.2      M     M       M      M    M
 32000  -32.4 -26.3   295   37   19   7.8   4.3      M     M       M      M    M
 30000  -28.1 -18.6   300   30   15   7.2   3.9   47.7 117.9     9.7      M    M
 29000  -25.9 -14.6   300   27   14   7.2   3.9   46.8 116.2     9.1      M    M
 28000  -23.8 -10.8   300   23   12   6.4   3.5   45.8 114.4     8.4      M    M
 27000  -21.9  -7.4   295   20   10   6.5   3.6   44.4 111.9     7.4      M    M
 26000  -20.0  -4.0   290   17    9   6.5   3.6   43.2 109.8     6.5      M    M
 25000  -18.1  -0.6   280   14    7   7.3   4.0   42.2 107.9     5.6      M    M
 24000  -15.7   3.7   270   13    7   8.1   4.4   41.4 106.5     5.0      M    M
 23000  -13.4   7.9   260   12    6   8.1   4.4   40.8 105.5     4.5      M    M
 22000  -11.0  12.2   250   11    6   7.2   4.0   40.3 104.6     4.1      M    M
 21000   -9.0  15.8   255   11    6   6.5   3.5   39.0 102.3     3.1      M    M
 20000   -7.1  19.2   260   11    6   6.5   3.5   37.9 100.2     2.2      M    M
 19500   -6.1  21.0   265   11    6   6.5   3.6   37.4  99.3     1.8      M    M
 19000   -5.2  22.6   265   11    6   6.0   3.3   36.8  98.2     1.2      M    M
 18500   -4.3  24.3   270   11    6   6.1   3.4   36.1  97.0     0.6      M    M
 18000   -3.4  25.9   275   12    6   6.6   3.6   35.5  96.0     0.1      M    M
 17500   -2.4  27.7   275   11    6   7.1   3.9   35.1  95.1    -0.4   1114  5.7
 17000   -1.4  29.5   275   11    6   7.1   3.9   34.6  94.3    -0.9   1069  5.4
 16500    0.3  32.5   275   10    5   7.8   4.3   34.1  93.3    -1.4    996  5.1
 16000    1.4  34.5   275    9    4   7.8   4.3   33.8  92.8    -1.6    946  4.8
 15500    2.6  36.7   275    8    4   7.9   4.3   33.4  92.2    -2.0    897  4.6
 15000    3.7  38.7   275    7    3   7.8   4.3   33.1  91.6    -2.3    848  4.3
 14500    4.9  40.8   275    6    3   8.7   4.8   32.9  91.2    -2.6    797  4.1
 14000    6.2  43.2   280    5    3   8.7   4.8   32.7  90.8    -2.8    745  3.8
 13500    7.4  45.3   285    5    3   8.6   4.7   32.5  90.6    -3.0    692  3.5
 13000    8.7  47.7   285    5    2   8.5   4.7   32.3  90.2    -3.3    640  3.3
 12500    9.9  49.8   290    4    2   8.4   4.6   32.1  89.8    -3.5    588  3.0
 12000   11.2  52.2   285    4    2   8.2   4.5   31.9  89.4    -3.7    536  2.7
 11500   12.4  54.3   275    4    2   8.2   4.5   31.6  89.0    -4.0    484  2.5
 11000   13.6  56.5   260    6    3   7.9   4.3   31.4  88.5    -4.2    433  2.2
 10500   14.8  58.6   255    7    4   4.6   2.5   31.1  88.0    -4.5    382  1.9
 10250   15.0  59.0   250    8    4   4.9   2.7   30.6  87.0    -5.0    368  1.9
 10000   15.6  60.1   245    9    5   9.4   5.2   30.5  86.9    -5.2    343  1.7
  9750   16.2  61.2   240   11    6   8.7   4.8   30.4  86.7    -5.3    319  1.6
  9500   16.8  62.2   235   14    7   7.5   4.1   30.3  86.5    -5.5    294  1.5
  9250   17.2  63.0   230   15    8   5.4   3.0   30.0  86.0    -5.8    274  1.4
  9000   17.6  63.7   230   17    9   6.3   3.5   29.7  85.5    -6.2    255  1.3
  8750   18.0  64.4   225   19   10   7.0   3.8   29.5  85.0    -6.5    234  1.2
  8500   18.5  65.3   225   21   11   6.6   3.6   29.2  84.6    -6.8    213  1.1
  8250   18.9  66.0   220   22   11   6.4   3.5   29.0  84.2    -7.1    192  1.0
  8000   19.4  66.9   220   23   12   6.6   3.6   28.7  83.7    -7.4    172  0.9
  7750   19.8  67.6   215   23   12   6.9   3.8   28.5  83.3    -7.7    151  0.8
  7500   20.3  68.5   215   23   12   6.5   3.5   28.3  82.9    -7.9    129  0.7
  7250   20.8  69.4   210   23   12   5.9   3.2   28.0  82.4    -8.2    107  0.5
  7000   21.3  70.3   210   22   11   6.6   3.6   27.7  81.9    -8.5     85  0.4
  6750   21.8  71.2   210   22   11   4.0   2.2   27.4  81.4    -8.7     64  0.3
  6500   21.7  71.1   205   21   11  -5.2  -2.8   26.7  80.0    -9.5     57  0.3
  6250   21.1  70.0   205   20   10  -8.1  -4.4   25.3  77.6   -10.9     69  0.3
  6000   20.4  68.7   205   19   10 -10.8  -5.9   24.0  75.2   -12.3     81  0.4
  5750   19.4  66.9   200   18    9 -12.3  -6.7   22.3  72.1   -14.1    105  0.5
  5500   18.8  65.8   195   14    7   0.2   0.1   21.0  69.9   -15.5    115  0.6

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

           07/24/2017 at 0900 MDT          |       07/24/2017 at 1200 MDT
                                           |
K index... +20.3  LI... +0.4               | K index... +22.3  LI... -1.2
CAPE... +3.4  CIN... -3.7                  | CAPE... +41.7  CIN... -48.7
                                           |
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 -65.8 -86.4  300  22 12   1.2   0.7 | -64.8 -84.6  275  18  9   1.1   0.6
 45000 -61.2 -78.2  295  41 21   6.1   3.4 | -60.6 -77.1  285  35 18   5.6   3.1
 40000 -51.5 -60.7  290  59 30   8.2   4.5 | -51.4 -60.5  290  52 27   8.8   4.8
 38000 -46.6 -51.9  290  61 31   8.2   4.5 | -46.1 -51.0  285  53 27   8.8   4.8
 36000 -41.7 -43.1  285  63 32   7.9   4.4 | -40.9 -41.6  275  54 28   8.1   4.4
 34000 -37.3 -35.1  290  49 25   7.4   4.1 | -36.3 -33.3  285  43 22   6.7   3.7
 32000 -32.8 -27.0  295  36 18   7.4   4.1 | -32.3 -26.1  290  33 17   7.4   4.0
 30000 -28.1 -18.6  300  26 13   6.9   3.8 | -27.8 -18.0  290  27 14   7.5   4.1
 29000 -26.0 -14.8  300  21 11   7.0   3.8 | -25.6 -14.1  290  24 12   7.5   4.1
 28000 -24.0 -11.2  300  18  9   7.3   4.0 | -23.4 -10.1  285  21 11   7.1   3.9
 27000 -21.8  -7.2  290  16  8   7.2   4.0 | -21.3  -6.3  280  20 10   7.2   3.9
 26000 -19.6  -3.3  275  15  8   7.2   4.0 | -19.1  -2.4  275  18  9   7.2   4.0
 25000 -17.5   0.5  260  15  8   7.3   4.0 | -17.0   1.4  270  17  9   7.0   3.9
 24000 -15.3   4.5  250  14  7   7.4   4.0 | -15.0   5.0  260  16  8   6.9   3.8
 23000 -13.2   8.2  240  13  7   7.4   4.1 | -13.0   8.6  250  15  8   7.0   3.8
 22000 -11.0  12.2  230  12  6   6.6   3.6 | -11.0  12.2  240  14  7   6.3   3.5
 21000  -9.3  15.3  250  11  5   5.9   3.3 |  -9.3  15.3  250  12  6   5.7   3.1
 20000  -7.6  18.3  270  10  5   5.9   3.3 |  -7.6  18.3  265   9  5   5.7   3.1
 19500  -6.7  19.9  280  11  6   6.0   3.3 |  -6.7  19.9  270   9  4   5.7   3.1
 19000  -5.7  21.7  290  11  6   7.3   4.0 |  -5.8  21.6  290   8  4   6.8   3.7
 18500  -4.7  23.5  295  12  6   7.2   3.9 |  -4.8  23.4  310   9  5   6.7   3.7
 18000  -3.6  25.5  300  13  7   6.9   3.8 |  -3.8  25.2  325  10  5   6.8   3.7
 17500  -2.6  27.3  310  13  6   6.7   3.7 |  -2.8  27.0  335  10  5   6.9   3.8
 17000  -1.6  29.1  315  12  6   6.7   3.7 |  -1.2  29.8  350  10  5   7.6   4.1
 16500  -0.5  31.1  320  12  6   7.8   4.3 |  -0.1  31.8  355  11  5   8.0   4.4
 16000   1.2  34.2  325  12  6   7.8   4.3 |   1.0  33.8  355  11  6   8.2   4.5
 15500   2.4  36.3  325  11  6   8.7   4.8 |   2.3  36.1  360  11  6   8.9   4.9
 15000   3.6  38.5  325  11  5   8.7   4.8 |   3.6  38.5  360  11  6   8.9   4.9
 14500   4.9  40.8  325  10  5   8.6   4.7 |   4.9  40.8  005  10  5   9.1   5.0
 14000   6.1  43.0  325   9  5   8.6   4.7 |   6.3  43.3  005  10  5   9.1   5.0
 13500   7.4  45.3  325   8  4   8.6   4.7 |   7.6  45.7  005   9  5   8.5   4.7
 13000   8.6  47.5  320   7  4   8.6   4.7 |   8.8  47.8  360   8  4   8.3   4.6
 12500   9.9  49.8  320   6  3   8.5   4.6 |  10.1  50.2  355   6  3   8.5   4.7
 12000  11.1  52.0  320   5  3   8.3   4.6 |  11.4  52.5  345   5  3   8.7   4.8
 11500  12.3  54.1  315   4  2   8.2   4.5 |  12.7  54.9  335   4  2   8.4   4.6
 11000  13.6  56.5  315   4  2   7.9   4.4 |  13.8  56.8  325   4  2   7.9   4.3
 10500  14.8  58.6  315   5  2   4.7   2.6 |  15.0  59.0  315   3  2   5.2   2.9
 10250  15.0  59.0  315   5  2   5.3   2.9 |  15.3  59.5  315   3  2   5.7   3.1
 10000  15.7  60.3  310   5  3  10.0   5.5 |  15.9  60.6  305   3  2   9.7   5.3
  9750  16.3  61.3  310   5  3   9.3   5.1 |  16.6  61.9  300   3  2   8.8   4.8
  9500  17.0  62.6  305   6  3   7.5   4.1 |  17.2  63.0  290   3  1   8.4   4.6
  9250  17.4  63.3  300   6  3   5.2   2.9 |  17.8  64.0  285   3  1   7.8   4.3
  9000  17.8  64.0  295   6  3   6.8   3.7 |  18.3  64.9  275   3  1   8.6   4.7
  8750  18.3  64.9  285   7  4   7.6   4.2 |  18.9  66.0  270   3  1   8.6   4.7
  8500  18.8  65.8  280   8  4   6.9   3.8 |  19.5  67.1  265   3  1   9.1   5.0
  8250  19.3  66.7  270   8  4   6.3   3.5 |  20.2  68.4  260   3  1   9.6   5.2
  8000  19.7  67.5  265   8  4   6.3   3.5 |  20.9  69.6  260   3  1   9.8   5.4
  7750  20.2  68.4  260   9  5   6.3   3.5 |  21.6  70.9  260   3  1  10.1   5.6
  7500  20.6  69.1  255   9  5   5.0   2.7 |  22.4  72.3  260   3  1  10.0   5.5
  7250  20.9  69.6  250   9  5   4.0   2.2 |  23.1  73.6  260   3  1  10.0   5.5
  7000  21.2  70.2  245   9  5   4.2   2.3 |  23.9  75.0  260   3  1  10.2   5.6
  6750  21.5  70.7  245   9  5   4.2   2.3 |  24.6  76.3  260   3  2  10.7   5.9
  6500  21.8  71.2  240   9  5   4.4   2.4 |  25.4  77.7  260   3  2  10.7   5.9
  6250  22.1  71.8  235   8  4   5.3   2.9 |  26.2  79.2  260   3  2  11.3   6.2
  6000  22.4  72.3  225   7  4   2.8   1.5 |  27.0  80.6  260   3  2   8.7   4.8
  5750  22.6  72.7  215   7  3   8.5   4.6 |  27.7  81.9  260   3  2  13.9   7.6
  5500  23.9  75.0  210   6  3  25.4  13.9 |  29.4  84.9  260   3  1  31.2  17.1

           07/24/2017 at 1500 MDT          |       07/24/2017 at 1800 MDT
                                           |
K index... +21.4  LI... -0.9               | K index... +27.2  LI... -0.7
CAPE... +19.5  CIN... -15.2                | CAPE... +26.5  CIN... -7.4
                                           |
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 -65.6 -86.1  265  21 11   0.9   0.5 | -65.8 -86.4  265  24 12   1.1   0.6
 45000 -61.1 -78.0  280  37 19   6.6   3.6 | -61.0 -77.8  280  41 21   6.6   3.6
 40000 -50.9 -59.6  285  53 27   8.0   4.4 | -50.7 -59.3  285  59 30   8.3   4.6
 38000 -46.0 -50.8  275  53 27   8.0   4.4 | -45.7 -50.3  280  57 29   8.3   4.6
 36000 -41.2 -42.2  270  53 27   8.0   4.4 | -40.7 -41.3  280  55 28   8.1   4.5
 34000 -35.9 -32.6  280  46 24   7.9   4.3 | -35.4 -31.7  275  45 23   7.9   4.3
 32000 -31.1 -24.0  285  40 21   7.9   4.3 | -30.7 -23.3  275  35 18   8.2   4.5
 30000 -26.9 -16.4  285  31 16   7.1   3.9 | -26.3 -15.3  280  28 15   7.3   4.0
 29000 -24.8 -12.6  280  27 14   7.1   3.9 | -24.1 -11.4  280  25 13   7.3   4.0
 28000 -22.6  -8.7  280  23 12   7.0   3.9 | -22.0  -7.6  280  22 12   6.5   3.6
 27000 -20.6  -5.1  280  21 11   7.1   3.9 | -20.0  -4.0  280  20 10   6.6   3.6
 26000 -18.5  -1.3  275  19 10   7.1   3.9 | -18.1  -0.6  275  18  9   6.6   3.6
 25000 -16.4   2.5  275  17  9   6.9   3.8 | -16.1   3.0  275  16  8   6.7   3.7
 24000 -14.4   6.1  275  17  9   6.8   3.7 | -14.1   6.6  275  16  8   6.8   3.7
 23000 -12.4   9.7  275  16  8   6.8   3.7 | -12.2  10.0  280  15  8   6.8   3.8
 22000 -10.4  13.3  280  16  8   6.1   3.4 | -10.2  13.6  285  15  8   6.5   3.5
 21000  -8.7  16.3  280  14  7   5.7   3.1 |  -8.4  16.9  295  13  7   6.1   3.4
 20000  -7.1  19.2  280  11  6   5.7   3.2 |  -6.6  20.1  310  12  6   6.1   3.4
 19500  -6.3  20.7  280  10  5   5.8   3.2 |  -5.7  21.7  320  12  6   6.1   3.4
 19000  -5.4  22.3  285   9  5   6.8   3.7 |  -4.8  23.4  325  11  6   6.6   3.6
 18500  -4.4  24.1  295   9  5   6.8   3.7 |  -3.9  25.0  330   9  5   6.6   3.6
 18000  -3.4  25.9  305   9  5   7.3   4.0 |  -3.0  26.6  340   7  4   6.8   3.7
 17500  -1.6  29.1  325   7  4   7.8   4.3 |  -1.3  29.7  010   4  2   7.0   3.8
 17000  -0.4  31.3  345   7  3   7.6   4.2 |  -0.2  31.6  050   4  2   7.0   3.8
 16500   0.7  33.3  360   6  3   7.5   4.1 |   0.8  33.4  065   4  2   7.0   3.8
 16000   1.8  35.2  015   7  3   7.6   4.2 |   1.8  35.2  085   4  2   7.1   3.9
 15500   3.0  37.4  025   6  3   8.2   4.5 |   2.8  37.0  100   4  2   8.1   4.5
 15000   4.1  39.4  030   6  3   8.2   4.5 |   4.0  39.2  105   4  2   8.1   4.4
 14500   5.3  41.5  035   6  3   8.8   4.8 |   5.1  41.2  110   4  2   9.0   5.0
 14000   6.6  43.9  040   5  3   8.8   4.8 |   6.5  43.7  115   3  2   9.0   5.0
 13500   7.9  46.2  050   4  2   9.1   5.0 |   7.8  46.0  120   3  2   9.5   5.2
 13000   9.2  48.6  050   4  2   9.2   5.0 |   9.2  48.6  125   3  1   9.7   5.3
 12500  10.5  50.9  055   3  2   9.0   4.9 |  10.7  51.3  125   2  1   9.8   5.4
 12000  11.8  53.2  055   2  1   8.9   4.9 |  12.1  53.8  130   2  1   9.8   5.4
 11500  13.1  55.6  050   1  1   9.1   5.0 |  13.6  56.5  140   2  1   9.5   5.2
 11000  14.5  58.1  045   1  0   9.2   5.1 |  14.9  58.8  160   1  1   8.7   4.8
 10500  15.9  60.6  025   1  0   5.8   3.2 |  16.3  61.3  200   1  1   5.8   3.2
 10250  16.2  61.2  020   1  0   7.1   3.9 |  16.6  61.9  210   1  1   7.4   4.1
 10000  17.0  62.6  005   1  0  12.4   6.8 |  17.5  63.5  225   1  1  12.4   6.8
  9750  17.8  64.0  345   1  0  11.6   6.3 |  18.3  64.9  235   1  1  11.6   6.4
  9500  18.7  65.7  330   1  0   9.6   5.3 |  19.2  66.6  245   2  1   9.8   5.4
  9250  19.3  66.7  320   1  0   8.3   4.5 |  19.8  67.6  250   2  1   8.1   4.4
  9000  20.0  68.0  315   1  0  10.8   5.9 |  20.5  68.9  255   2  1  10.0   5.5
  8750  20.8  69.4  310   1  0  11.2   6.1 |  21.3  70.3  255   2  1  10.1   5.6
  8500  21.7  71.1  305   1  1  10.8   5.9 |  22.0  71.6  260   2  1  10.7   5.8
  8250  22.4  72.3  300   1  1  10.6   5.8 |  22.8  73.0  260   2  1  11.8   6.5
  8000  23.2  73.8  295   1  1   9.9   5.4 |  23.7  74.7  260   2  1  10.2   5.6
  7750  23.9  75.0  295   1  1   9.1   5.0 |  24.4  75.9  265   3  1   8.7   4.8
  7500  24.6  76.3  295   1  1  10.0   5.5 |  25.0  77.0  265   3  1   9.5   5.2
  7250  25.4  77.7  290   2  1  10.8   5.9 |  25.8  78.4  265   3  1   9.7   5.3
  7000  26.2  79.2  290   2  1  10.2   5.6 |  26.5  79.7  265   3  2  10.0   5.5
  6750  26.9  80.4  290   2  1   9.7   5.3 |  27.3  81.1  265   3  2  10.7   5.9
  6500  27.7  81.9  285   2  1  10.6   5.8 |  28.1  82.6  270   3  2  10.3   5.7
  6250  28.5  83.3  285   2  1  11.9   6.6 |  28.8  83.8  270   3  2  10.1   5.5
  6000  29.4  84.9  285   2  1   9.7   5.3 |  29.6  85.3  270   3  2   9.6   5.3
  5750  30.1  86.2  285   2  1  13.8   7.6 |  30.4  86.7  270   3  2  12.5   6.9
  5500  31.7  89.1  285   2  1  28.9  15.8 |  31.6  88.9  265   3  2  20.4  11.2
________________________________________________________________________________

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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