Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 281245
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0645 MDT Tuesday, July 28, 2015

This forecast is for Tuesday, July 28, 2015:

If the trigger temperature of 82.8 F/28.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 473 ft/min (2.4 m/s)
   Maximum height of thermals.................. 11353 ft MSL (6068 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1330 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8866 ft MSL (3580 ft AGL)
Thermal soaring outlook for Wednesday 07/29.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 13668 ft MSL (8383 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 15394 ft MSL (10109 ft AGL)
Wave soaring outlook for Wednesday 07/29....... Poor

Remarks... Drier and slightly cooler airmass over northeast colorado today. Weak
           to moderate southwest flow aloft.

Sunrise/Sunset.................... 05:54:41 / 20:17:32 MDT
Total possible sunshine........... 14 hr 22 min 52 sec (862 min 52 sec)
Altitude of sun at 13:05:55 MDT... 69.13 degrees

Upper air data from rawinsonde observation taken on 07/28/2015 at 0600 MDT

Freezing level.................. 16898 ft MSL (11613 ft AGL)
Convective condensation level... 20093 ft MSL (14808 ft AGL)
Lifted condensation level....... 17455 ft MSL (12170 ft AGL)
Lifted index.................... +2.8
K index......................... -15.5

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -68.0 -90.4   235   39   20   5.0   2.7   78.5 173.3    28.3      M    M
 45000  -61.4 -78.5   240   54   28   5.2   2.8   65.1 149.3    22.0      M    M
 40000  -51.9 -61.4   230   62   32   6.1   3.3   57.3 135.1    18.3      M    M
 38000  -47.4 -53.3   230   63   32   5.8   3.2   55.2 131.4    17.3      M    M
 36000  -43.3 -45.9   230   57   29   9.2   5.1   52.8 127.0    16.1      M    M
 34000  -38.0 -36.4   230   56   29   6.6   3.6   50.6 123.1    15.0      M    M
 32000  -34.1 -29.4   230   55   28   6.4   3.5   48.2 118.8    13.5      M    M
 30000  -29.0 -20.2   240   52   27   9.5   5.2   47.3 117.1    13.2      M    M
 29000  -27.0 -16.6   240   48   25   4.2   2.3   46.0 114.7    12.3      M    M
 28000  -25.8 -14.4   240   44   23   5.5   3.0   43.8 110.9    10.8      M    M
 27000  -23.4 -10.1   240   40   21   8.4   4.6   43.1 109.6    10.4      M    M
 26000  -20.8  -5.4   235   37   19   8.4   4.6   42.6 108.7    10.1      M    M
 25000  -18.5  -1.3   235   33   17   5.3   2.9   41.9 107.5     9.7      M    M
 24000  -16.4   2.5   235   32   16   7.4   4.1   40.9 105.6     8.9      M    M
 23000  -15.2   4.6   230   31   16   2.2   1.2   38.9 101.9     7.3      M    M
 22000  -12.9   8.8   225   29   15   9.1   5.0   38.0 100.5     6.7      M    M
 21000  -10.2  13.6   225   28   14   9.0   4.9   37.8 100.0     6.6      M    M
 20000   -7.5  18.5   220   27   14   9.0   5.0   37.6  99.7     6.5      M    M
 19500   -6.1  21.0   220   27   14   9.4   5.2   37.5  99.4     6.4      M    M
 19000   -5.0  23.0   220   27   14   5.1   2.8   37.0  98.7     6.1      M    M
 18500   -4.2  24.4   215   26   13   4.9   2.7   36.2  97.2     5.4      M    M
 18000   -3.2  26.2   215   25   13   8.6   4.7   35.7  96.2     4.9      M    M
 17500   -1.9  28.6   215   25   13   8.8   4.8   35.5  95.9     4.8      M    M
 17000   -0.6  30.9   210   24   12   8.8   4.8   35.3  95.6     4.7      M    M
 16500    1.4  34.5   205   23   12   8.8   4.8   35.1  95.2     4.5      M    M
 16000    2.7  36.9   205   23   12   9.0   4.9   35.0  94.9     4.4      M    M
 15500    3.9  39.0   210   25   13   6.4   3.5   34.6  94.4     4.2      M    M
 15000    4.8  40.6   210   26   13   6.3   3.4   34.1  93.3     3.6      M    M
 14500    5.7  42.3   220   22   11   6.6   3.6   33.5  92.3     3.1      M    M
 14000    6.4  43.5   225   18    9   2.9   1.6   32.8  91.0     2.3      M    M
 13500    6.6  43.9   230   11    6   3.4   1.9   31.5  88.7     1.0      M    M
 13000    7.5  45.5   250    7    3   9.1   5.0   31.1  87.9     0.5      M    M
 12500    8.8  47.8   260   10    5   8.8   4.8   30.9  87.6     0.4      M    M
 12000   10.1  50.2   260   14    7   8.8   4.8   30.8  87.4     0.2      M    M
 11500   11.4  52.5   250   17    9   8.8   4.8   30.6  87.0     0.0      M    M
 11000   12.7  54.9   245   19   10   8.8   4.8   30.4  86.7    -0.1    430  2.2
 10500   14.0  57.2   240   22   11   8.9   4.9   30.2  86.4    -0.3    376  1.9
 10250   14.7  58.5   240   23   12   9.1   5.0   30.2  86.4    -0.3    348  1.8
 10000   15.4  59.7   240   23   12  10.2   5.6   30.2  86.3    -0.4    320  1.6
  9750   16.1  61.0   240   20   10   7.0   3.9   30.2  86.3    -0.4    291  1.5
  9500   16.3  61.3   235   17    9  -2.1  -1.1   29.6  85.3    -1.0    279  1.4
  9250   16.1  61.0   230   14    7   3.0   1.7   28.7  83.6    -1.9    278  1.4
  9000   16.4  61.5   225   11    6  -0.9  -0.5   28.3  82.9    -2.3    261  1.3
  8750   15.8  60.4   220   10    5  -7.1  -3.9   26.9  80.5    -3.7    273  1.4
  8500   15.6  60.1   215    9    5   3.0   1.6   26.1  79.0    -4.6    269  1.4
  8250   15.9  60.6   210    8    4   5.3   2.9   25.7  78.2    -5.0    253  1.3
  8000   16.2  61.2   200    7    4   2.6   1.4   25.3  77.5    -5.5    236  1.2
  7750   16.2  61.2   195    6    3  -4.7  -2.6   24.5  76.0    -6.3    231  1.2
  7500   15.6  60.1   190    4    2  -8.6  -4.7   23.1  73.6    -7.6    239  1.2
  7250   15.1  59.2   180    3    2  -5.8  -3.2   21.8  71.3    -8.8    247  1.3
  7000   15.0  59.0   150    2    1   2.6   1.4   20.9  69.6    -9.7    245  1.2
  6750   15.4  59.7   115    5    3   7.2   3.9   20.6  69.1   -10.1    224  1.1
  6500   15.8  60.4   110    9    5   6.0   3.3   20.4  68.6   -10.4    203  1.0
  6250   16.3  61.3   105   13    7   6.4   3.5   20.1  68.2   -10.7    183  0.9
  6000   16.7  62.1   105   17    9   6.1   3.3   19.8  67.7   -11.0    162  0.8
  5750   17.2  63.0   110   13    7   6.9   3.8   19.6  67.2   -11.3    142  0.7
  5500   17.6  63.7   115   10    5   3.9   2.2   19.3  66.8   -11.6    121  0.6

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

           07/28/2015 at 0900 MDT          |       07/28/2015 at 1200 MDT
                                           |
K index... -2.1  LI... +4.8                | K index... +3.3  LI... +4.6
CAPE... 0.0  CIN... M                      | CAPE... 0.0  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 -64.4 -83.9  235  36 18   1.7   0.9 | -64.6 -84.3  230  38 20   1.8   1.0
 45000 -60.0 -76.0  235  51 26   5.6   3.1 | -60.0 -76.0  235  56 29   5.7   3.1
 40000 -51.5 -60.7  235  65 33   6.4   3.5 | -51.3 -60.3  240  66 34   6.4   3.5
 38000 -47.6 -53.7  235  62 32   6.4   3.5 | -47.4 -53.3  240  63 33   6.4   3.5
 36000 -43.3 -45.9  235  60 31   6.8   3.8 | -43.1 -45.6  235  60 31   6.7   3.7
 34000 -38.8 -37.8  235  57 29   7.5   4.1 | -38.8 -37.8  235  57 29   7.1   3.9
 32000 -34.3 -29.7  235  54 28   7.7   4.2 | -34.5 -30.1  235  54 28   7.3   4.0
 30000 -29.6 -21.3  235  49 25   7.9   4.3 | -29.6 -21.3  235  50 26   8.3   4.6
 29000 -27.2 -17.0  235  46 24   7.9   4.3 | -27.1 -16.8  235  48 25   8.4   4.6
 28000 -24.9 -12.8  235  44 23   7.0   3.9 | -24.6 -12.3  240  46 24   7.1   3.9
 27000 -22.8  -9.0  235  41 21   6.9   3.8 | -22.5  -8.5  240  43 22   6.8   3.8
 26000 -20.7  -5.3  235  38 20   6.9   3.8 | -20.5  -4.9  240  40 21   6.8   3.8
 25000 -18.7  -1.7  235  36 18   7.0   3.8 | -18.4  -1.1  240  37 19   6.9   3.8
 24000 -16.5   2.3  240  34 18   7.5   4.1 | -16.3   2.7  245  35 18   6.9   3.8
 23000 -14.2   6.4  240  33 17   7.5   4.1 | -14.3   6.3  245  34 17   6.9   3.8
 22000 -11.9  10.6  240  32 17   7.2   4.0 | -12.2  10.0  250  33 17   7.0   3.8
 21000 -10.0  14.0  235  31 16   6.5   3.5 | -10.1  13.8  250  31 16   7.1   3.9
 20000  -8.0  17.6  235  31 16   6.5   3.5 |  -7.9  17.8  250  30 16   7.1   3.9
 19500  -7.1  19.2  230  30 16   6.5   3.6 |  -6.9  19.6  245  30 15   7.2   3.9
 19000  -6.1  21.0  230  30 15   6.0   3.3 |  -5.9  21.4  245  29 15   6.3   3.5
 18500  -5.2  22.6  230  29 15   6.0   3.3 |  -4.4  24.1  245  28 14   6.4   3.5
 18000  -3.9  25.0  230  27 14   6.8   3.7 |  -3.5  25.7  245  27 14   6.1   3.3
 17500  -2.9  26.8  230  27 14   6.8   3.8 |  -2.6  27.3  245  26 14   6.1   3.3
 17000  -1.9  28.6  235  26 13   7.3   4.0 |  -1.7  28.9  245  26 13   6.1   3.4
 16500  -0.7  30.7  235  25 13   7.9   4.4 |  -0.8  30.6  245  25 13   6.1   3.4
 16000   0.5  32.9  235  25 13   8.0   4.4 |   0.1  32.2  245  24 12   6.1   3.4
 15500   1.7  35.1  240  24 13   8.2   4.5 |   1.0  33.8  245  23 12   7.2   4.0
 15000   2.9  37.2  245  24 12   8.2   4.5 |   2.0  35.6  250  22 12   7.3   4.0
 14500   4.0  39.2  250  24 12   7.5   4.1 |   3.0  37.4  250  21 11   7.2   4.0
 14000   5.1  41.2  255  23 12   7.5   4.1 |   4.1  39.4  250  19 10   7.3   4.0
 13500   6.2  43.2  260  23 12   8.6   4.7 |   5.1  41.2  245  16  8   8.6   4.7
 13000   7.6  45.7  260  22 11   9.3   5.1 |   6.5  43.7  245  14  7   9.4   5.1
 12500   9.0  48.2  265  21 11   8.9   4.9 |   7.9  46.2  240  13  6   9.2   5.0
 12000  10.2  50.4  265  20 10   8.1   4.4 |   9.3  48.7  240  11  6   8.7   4.8
 11500  11.4  52.5  265  19 10   7.4   4.1 |  10.6  51.1  240  10  5   8.0   4.4
 11000  12.2  54.0  265  17  9   5.5   3.0 |  11.6  52.9  240   9  5   6.2   3.4
 10500  13.1  55.6  260  15  8   4.2   2.3 |  12.5  54.5  240   7  4   4.2   2.3
 10250  13.2  55.8  260  15  8   2.3   1.3 |  12.7  54.9  240   7  4   3.5   1.9
 10000  13.4  56.1  255  14  7   3.5   1.9 |  13.1  55.6  235   6  3   6.3   3.5
  9750  13.7  56.7  250  12  6   4.1   2.3 |  13.6  56.5  230   6  3   6.5   3.5
  9500  13.9  57.0  245  11  6   3.3   1.8 |  14.0  57.2  225   6  3   5.5   3.0
  9250  14.1  57.4  240  10  5   2.0   1.1 |  14.3  57.7  220   5  3   4.1   2.3
  9000  14.2  57.6  240  10  5   1.8   1.0 |  14.6  58.3  210   6  3   4.7   2.6
  8750  14.3  57.7  235   9  5   2.1   1.2 |  15.0  59.0  200   6  3   6.0   3.3
  8500  14.4  57.9  230   9  4   1.4   0.8 |  15.4  59.7  195   6  3   3.6   1.9
  8250  14.5  58.1  230   8  4   0.7   0.4 |  15.4  59.7  180   5  3   1.2   0.6
  8000  14.5  58.1  230   8  4   0.4   0.2 |  15.5  59.9  160   5  2   1.7   1.0
  7750  14.4  57.9  230   8  4  -0.6  -0.3 |  15.6  60.1  135   5  3   2.1   1.2
  7500  14.4  57.9  230   7  4  -0.0  -0.0 |  15.8  60.4  110   6  3   7.1   3.9
  7250  14.4  57.9  225   5  3   0.9   0.5 |  16.5  61.7  110   6  3  10.4   5.7
  7000  14.5  58.1  220   4  2  -0.2  -0.1 |  17.2  63.0  110   6  3   9.5   5.2
  6750  14.5  58.1  210   2  1   2.2   1.2 |  17.9  64.2  105   6  3  10.0   5.5
  6500  14.8  58.6  145   1  1   8.0   4.4 |  18.7  65.7  105   6  3  10.6   5.8
  6250  15.5  59.9  120   2  1   9.4   5.2 |  19.5  67.1  105   6  3  10.4   5.7
  6000  16.2  61.2  110   3  1   9.8   5.4 |  20.3  68.5  105   6  3  11.4   6.2
  5750  17.1  62.8  110   3  2  14.0   7.7 |  21.3  70.3  105   5  3  17.8   9.7
  5500  18.3  64.9  105   3  2  18.1   9.9 |  23.0  73.4  105   5  3  25.3  13.9

           07/28/2015 at 1500 MDT          |       07/28/2015 at 1800 MDT
                                           |
K index... +18.1  LI... +1.4               | K index... +24.0  LI... -0.7
CAPE... 0.0  CIN... -0.3                   | CAPE... +16.3  CIN... -96.7
                                           |
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 -64.9 -84.8  230  43 22   1.0   0.6 | -65.3 -85.5  235  46 24   1.0   0.6
 45000 -60.9 -77.6  230  61 31   6.3   3.4 | -61.2 -78.2  235  65 33   6.5   3.6
 40000 -50.9 -59.6  235  68 35   6.7   3.7 | -50.8 -59.4  235  69 35   7.2   3.9
 38000 -46.9 -52.4  235  65 34   6.7   3.7 | -46.5 -51.7  235  68 35   7.2   3.9
 36000 -42.8 -45.0  235  62 32   6.9   3.8 | -42.2 -44.0  235  66 34   7.4   4.0
 34000 -38.5 -37.3  235  59 30   7.4   4.0 | -37.5 -35.5  235  63 32   7.8   4.3
 32000 -34.0 -29.2  240  55 28   7.3   4.0 | -32.8 -27.0  240  59 30   7.9   4.3
 30000 -29.5 -21.1  240  51 26   7.7   4.2 | -28.6 -19.5  240  54 28   6.9   3.8
 29000 -26.6 -15.9  240  48 25   7.7   4.2 | -26.1 -15.0  245  51 26   6.9   3.8
 28000 -24.3 -11.7  240  46 24   7.0   3.9 | -24.0 -11.2  245  48 25   6.8   3.8
 27000 -22.2  -8.0  240  44 22   7.1   3.9 | -21.9  -7.4  250  46 23   6.9   3.8
 26000 -20.0  -4.0  240  41 21   7.1   3.9 | -19.9  -3.8  250  43 22   6.9   3.8
 25000 -17.9  -0.2  245  39 20   7.1   3.9 | -17.8  -0.0  255  41 21   6.5   3.6
 24000 -15.8   3.6  245  37 19   7.0   3.8 | -16.0   3.2  255  39 20   6.0   3.3
 23000 -13.7   7.3  250  35 18   7.0   3.8 | -14.3   6.3  255  37 19   6.1   3.3
 22000 -11.6  11.1  255  33 17   6.6   3.6 | -12.5   9.5  255  36 18   6.1   3.3
 21000  -9.8  14.4  255  34 17   6.3   3.4 | -10.8  12.6  255  33 17   6.1   3.3
 20000  -7.9  17.8  255  34 18   6.3   3.5 |  -9.1  15.6  255  30 16   6.3   3.5
 19500  -7.0  19.4  255  35 18   6.4   3.5 |  -8.2  17.2  255  29 15   6.5   3.6
 19000  -6.2  20.8  255  34 18   4.9   2.7 |  -7.2  19.0  255  27 14   8.4   4.6
 18500  -5.5  22.1  255  33 17   5.3   2.9 |  -6.0  21.2  250  26 13   8.2   4.5
 18000  -4.8  23.4  255  32 16   6.1   3.3 |  -4.9  23.2  250  25 13   7.9   4.3
 17500  -3.9  25.0  255  29 15   6.6   3.6 |  -3.7  25.3  250  24 12   7.7   4.2
 17000  -3.0  26.6  250  27 14   6.7   3.7 |  -2.5  27.5  250  23 12   7.7   4.2
 16500  -1.9  28.6  250  25 13   9.3   5.1 |  -1.4  29.5  245  22 11   8.2   4.5
 16000  -0.5  31.1  245  23 12   9.1   5.0 |  -0.1  31.8  245  21 11   8.2   4.5
 15500   0.8  33.4  245  22 11   8.4   4.6 |   1.5  34.7  235  20 10   6.9   3.8
 15000   2.7  36.9  245  19 10   8.2   4.5 |   2.5  36.5  230  19 10   7.1   3.9
 14500   3.9  39.0  240  18  9   7.8   4.3 |   3.5  38.3  220  19 10   6.0   3.3
 14000   5.0  41.0  240  16  8   7.9   4.3 |   4.3  39.7  210  19 10   6.1   3.3
 13500   6.1  43.0  235  15  8   7.6   4.1 |   5.2  41.4  200  19 10   7.0   3.9
 13000   7.3  45.1  230  14  7   7.4   4.1 |   6.3  43.3  195  18  9   7.3   4.0
 12500   8.4  47.1  225  12  6   6.8   3.7 |   7.3  45.1  190  17  9   7.3   4.0
 12000   9.3  48.7  220  11  6   6.2   3.4 |   8.4  47.1  185  14  7   7.3   4.0
 11500  10.2  50.4  210   9  5   5.5   3.0 |   9.5  49.1  175  11  6   7.2   4.0
 11000  10.8  51.4  195   8  4   4.3   2.3 |  10.5  50.9  155   9  5   6.8   3.7
 10500  11.3  52.3  175   7  3   1.7   0.9 |  11.6  52.9  125   9  5   2.9   1.6
 10250  11.4  52.5  170   7  3   4.3   2.3 |  11.7  53.1  125   9  5   5.9   3.3
 10000  12.0  53.6  145   6  3   9.7   5.3 |  12.6  54.7  120   9  5  13.1   7.2
  9750  12.6  54.7  125   7  4   8.5   4.6 |  13.5  56.3  115   9  5  12.0   6.6
  9500  13.2  55.8  110   9  4   8.2   4.5 |  14.3  57.7  110  10  5   9.5   5.2
  9250  13.7  56.7  110   9  5   8.2   4.5 |  14.9  58.8  105  10  5   7.1   3.9
  9000  14.4  57.9  110   9  5  10.6   5.8 |  15.5  59.9  105  10  5  10.3   5.7
  8750  15.3  59.5  110   9  5  12.0   6.6 |  16.4  61.5  100  10  5  11.3   6.2
  8500  16.1  61.0  110   9  5  10.6   5.8 |  17.2  63.0  100  10  5  10.5   5.7
  8250  16.9  62.4  110   9  5   9.5   5.2 |  17.9  64.2  100  10  5  10.2   5.6
  8000  17.6  63.7  110   9  5  10.0   5.5 |  18.7  65.7  095  10  5   9.8   5.4
  7750  18.4  65.1  110   9  4  10.3   5.7 |  19.4  66.9  095  10  5   9.4   5.2
  7500  19.1  66.4  105   9  4  10.2   5.6 |  20.1  68.2  095  10  5  10.2   5.6
  7250  19.9  67.8  105   9  4  10.2   5.6 |  20.9  69.6  095  10  5  10.6   5.8
  7000  20.6  69.1  105   9  4   9.9   5.4 |  21.7  71.1  090  10  5  10.2   5.6
  6750  21.3  70.3  105   9  4   9.9   5.4 |  22.4  72.3  090  10  5   9.9   5.4
  6500  22.1  71.8  105   9  4  10.5   5.8 |  23.1  73.6  090  10  5  10.2   5.6
  6250  22.9  73.2  105   8  4  11.2   6.2 |  23.9  75.0  090  10  5  10.7   5.9
  6000  23.7  74.7  105   8  4   9.3   5.1 |  24.7  76.5  090  10  5   9.4   5.1
  5750  24.5  76.1  105   8  4  15.2   8.3 |  25.4  77.7  085  10  5  12.2   6.7
  5500  26.2  79.2  100   8  4  30.2  16.6 |  26.6  79.9  085  10  5  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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