Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 071236
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0636 MDT Tuesday, July 7, 2015

This forecast is for Tuesday, July 7, 2015:

If the trigger temperature of 76.8 F/24.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 581 ft/min (3.0 m/s)
   Maximum height of thermals.................. 12326 ft MSL (7487 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1100 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................. 9075 ft MSL (4236 ft AGL)
Thermal soaring outlook for Wednesday 07/08.... Good

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 05:55:07 / 20:43:00 MDT
Total possible sunshine........... 14 hr 47 min 53 sec (887 min 53 sec)
Altitude of sun at 13:19:04 MDT... 73.40 degrees

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

Freezing level.................. 14688 ft MSL (9849 ft AGL)
Convective condensation level... 13528 ft MSL (8689 ft AGL)
Lifted condensation level....... 13418 ft MSL (8579 ft AGL)
Lifted index.................... -2.2
K index......................... +29.4

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  -63.2 -81.8   250   21   11   5.9   3.2   90.4 194.6    35.8      M    M
 45000  -59.2 -74.6   225   50   26   4.1   2.3   71.4 160.5    26.8      M    M
 40000  -55.9 -68.6   220   36   18   6.3   3.5   53.7 128.6    16.9      M    M
 38000  -51.3 -60.3   220   34   18   7.9   4.3   51.6 124.8    15.9      M    M
 36000  -46.5 -51.7   215   33   17   9.6   5.3   50.3 122.6    15.4      M    M
 34000  -40.7 -41.3   220   37   19   9.8   5.4   50.2 122.4    15.8      M    M
 32000  -35.7 -32.3   230   31   16   3.7   2.1   48.2 118.8    14.7      M    M
 30000  -30.8 -23.4   235   21   11   9.0   4.9   46.9 116.4    14.0      M    M
 29000  -28.4 -19.1   230   19   10   6.8   3.7   46.3 115.3    13.7      M    M
 28000  -26.3 -15.3   210   15    8   6.6   3.6   45.1 113.3    13.0      M    M
 27000  -24.0 -11.2   215   14    7   8.5   4.6   44.4 111.8    12.5      M    M
 26000  -22.2  -8.0   225   13    7   6.7   3.7   43.1 109.5    11.6      M    M
 25000  -19.8  -3.6   200   14    7   9.2   5.0   42.4 108.3    11.2      M    M
 24000  -17.9  -0.2   200   11    6   4.4   2.4   41.2 106.2    10.2      M    M
 23000  -16.6   2.1   195    8    4   4.5   2.4   39.3 102.8     8.7      M    M
 22000  -14.6   5.7   175    4    2   8.6   4.7   38.4 101.0     8.0      M    M
 21000  -12.0  10.4   205    5    3   8.7   4.8   37.9 100.3     7.7      M    M
 20000  -10.1  13.8   225    7    4  -1.7  -1.0   36.8  98.3     6.8      M    M
 19500   -9.6  14.7   215    9    5   6.7   3.7   35.8  96.4     5.8      M    M
 19000   -8.9  16.0   210   12    6   6.7   3.7   34.9  94.9     5.1      M    M
 18500   -7.7  18.1   215   13    7   8.1   4.5   34.6  94.3     4.8      M    M
 18000   -6.8  19.8   225   13    7   4.5   2.5   34.0  93.3     4.4      M    M
 17500   -5.8  21.6   220   14    7   4.9   2.7   32.7  90.9     3.2      M    M
 17000   -5.1  22.8   220   14    7   6.6   3.6   31.9  89.4     2.4      M    M
 16500   -3.9  25.0   215   15    7   8.2   4.5   31.7  89.0     2.2      M    M
 16000   -2.8  27.0   215   15    8   7.2   4.0   31.3  88.3     1.9      M    M
 15500   -1.7  28.9   215   14    7   6.6   3.6   30.8  87.5     1.5      M    M
 15000   -0.6  30.9   210   12    6   8.7   4.8   30.5  86.9     1.1      M    M
 14500    0.7  33.3   210   11    6   8.6   4.7   30.3  86.6     0.9      M    M
 14000    1.8  35.2   205   10    5   8.0   4.4   30.1  86.1     0.6      M    M
 13500    3.0  37.4   205    9    4   7.9   4.4   29.7  85.5     0.3      M    M
 13000    4.4  39.9   210    7    4   9.7   5.3   29.6  85.3     0.3      M    M
 12500    5.7  42.3   210    6    3   7.1   3.9   29.5  85.0     0.1      M    M
 12000    6.6  43.9   215    5    3   6.8   3.7   29.0  84.2    -0.4    550  2.8
 11500    7.6  45.7   190    7    3   6.8   3.7   28.5  83.2    -0.9    507  2.6
 11000    8.6  47.5   175    9    4   6.8   3.7   28.0  82.4    -1.4    463  2.4
 10500    9.5  49.1   165   11    6   7.0   3.8   27.5  81.6    -1.9    419  2.1
 10250   10.0  50.0   165   12    6   8.0   4.4   27.4  81.2    -2.1    396  2.0
 10000   10.7  51.3   165   12    6   8.4   4.6   27.3  81.1    -2.2    370  1.9
  9750   11.3  52.3   170   12    6   8.7   4.8   27.1  80.9    -2.3    345  1.8
  9500   11.9  53.4   170   11    6   7.3   4.0   27.1  80.7    -2.4    319  1.6
  9250   12.3  54.1   175   11    6   5.4   3.0   26.8  80.2    -2.7    298  1.5
  9000   12.7  54.9   175   11    6   5.4   3.0   26.4  79.6    -3.1    279  1.4
  8750   13.1  55.6   165    9    5   5.4   3.0   26.1  78.9    -3.4    260  1.3
  8500   13.5  56.3   150    8    4   5.4   3.0   25.7  78.3    -3.8    241  1.2
  8250   13.9  57.0   135    7    4   5.4   3.0   25.4  77.7    -4.1    222  1.1
  8000   14.3  57.7   115    7    4   5.4   3.0   25.1  77.2    -4.5    203  1.0
  7750   14.7  58.5   110    6    3   5.5   3.0   24.7  76.5    -4.8    184  0.9
  7500   15.1  59.2   105    6    3   5.3   2.9   24.4  75.9    -5.2    165  0.8
  7250   15.5  59.9   100    5    2   7.0   3.8   24.1  75.4    -5.5    145  0.7
  7000   16.1  61.0   095    4    2   8.4   4.6   24.0  75.2    -5.6    120  0.6
  6750   16.7  62.1   100    3    2   8.0   4.4   23.9  74.9    -5.8     95  0.5
  6500   17.2  63.0   105    2    1   8.1   4.5   23.7  74.7    -5.9     69  0.4
  6250   17.8  64.0   130    1    1   7.9   4.3   23.6  74.5    -6.1     44  0.2
  6000   18.4  65.1   200    1    0   8.7   4.8   23.5  74.3    -6.2     19  0.1
  5750   19.0  66.2   205    1    1   5.5   3.0   23.3  74.0    -6.4      M    M
  5500   19.2  66.6   195    1    1   2.5   1.3   22.8  73.1    -7.0      M    M
  5250   19.3  66.7   190    2    1   3.2   1.7   22.3  72.2    -7.6      M    M
  5000   19.5  67.1   180    2    1   3.5   1.9   21.8  71.3    -8.1      M    M

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

           07/07/2015 at 0900 MDT          |       07/07/2015 at 1200 MDT
                                           |
K index... +30.9  LI... +272.0             | K index... +29.0  LI... +270.7
CAPE... +85.3  CIN... -58.9                | CAPE... +394.2  CIN... -0.7
                                           |
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 -61.4 -78.5  235  23 12   1.9   1.0 | -62.0 -79.6  235  23 12   1.7   0.9
 45000 -58.5 -73.3  230  34 17   2.1   1.1 | -59.3 -74.7  235  31 16   2.0   1.1
 40000 -54.8 -66.6  220  35 18   7.5   4.1 | -55.6 -68.1  225  33 17   8.3   4.6
 38000 -50.4 -58.7  220  34 17   7.3   4.0 | -50.6 -59.1  220  34 17   8.2   4.5
 36000 -45.9 -50.6  220  32 16   7.3   4.0 | -45.6 -50.1  220  35 18   8.2   4.5
 34000 -41.0 -41.8  220  30 15   8.4   4.6 | -40.5 -40.9  220  34 17   8.6   4.7
 32000 -35.3 -31.5  220  27 14   8.4   4.6 | -34.7 -30.5  220  31 16   8.5   4.6
 30000 -30.8 -23.4  215  21 11   7.5   4.1 | -29.9 -21.8  215  25 13   8.0   4.4
 29000 -28.5 -19.3  210  18  9   7.6   4.2 | -27.6 -17.7  215  22 11   8.0   4.4
 28000 -26.3 -15.3  200  14  7   7.5   4.1 | -25.2 -13.4  215  19 10   7.6   4.1
 27000 -24.1 -11.4  205  14  7   7.5   4.1 | -23.1  -9.6  215  16  8   7.3   4.0
 26000 -21.9  -7.4  210  14  7   7.5   4.1 | -20.9  -5.6  215  14  7   7.3   4.0
 25000 -19.7  -3.5  215  13  7   7.6   4.2 | -18.8  -1.8  215  12  6   7.4   4.1
 24000 -17.6   0.3  225  12  6   6.9   3.8 | -16.8   1.8  220  11  5   6.5   3.6
 23000 -15.6   3.9  230  11  6   6.9   3.8 | -14.9   5.2  225  10  5   6.6   3.6
 22000 -13.5   7.7  240  10  5   6.9   3.8 | -12.9   8.8  230   9  5   6.6   3.6
 21000 -11.6  11.1  250  10  5   6.5   3.5 | -11.2  11.8  235   9  5   5.9   3.2
 20000  -9.8  14.4  255  11  5   6.5   3.6 |  -9.4  15.1  240  10  5   5.9   3.3
 19500  -8.8  16.2  255  11  5   6.5   3.6 |  -8.6  16.5  240  10  5   5.9   3.3
 19000  -7.9  17.8  260  11  6   6.4   3.5 |  -7.7  18.1  245  10  5   6.1   3.4
 18500  -7.0  19.4  260  11  5   6.4   3.5 |  -6.8  19.8  245  10  5   6.2   3.4
 18000  -6.0  21.2  260  11  5   6.3   3.5 |  -5.9  21.4  240  10  5   6.2   3.4
 17500  -5.2  22.6  260  10  5   5.4   3.0 |  -5.0  23.0  240  10  5   5.9   3.3
 17000  -4.4  24.1  260  10  5   5.5   3.0 |  -4.2  24.4  240  10  5   6.0   3.3
 16500  -3.6  25.5  260  10  5   5.8   3.2 |  -3.3  26.1  235  10  5   5.7   3.1
 16000  -2.8  27.0  260  10  5   5.8   3.2 |  -2.5  27.5  235  10  5   5.6   3.1
 15500  -1.5  29.3  260  10  5   5.3   2.9 |  -1.7  28.9  235  10  5   5.7   3.2
 15000  -0.8  30.6  260  10  5   5.3   2.9 |  -0.4  31.3  235   9  5   6.0   3.3
 14500  -0.0  32.0  260   9  5   5.4   3.0 |   0.5  32.9  235   8  4   6.3   3.5
 14000   0.8  33.4  260  10  5   5.6   3.1 |   1.4  34.5  240   8  4   6.5   3.6
 13500   1.6  34.9  265  10  5   6.8   3.7 |   2.4  36.3  240   8  4   6.6   3.6
 13000   2.8  37.0  265  10  5   8.3   4.5 |   3.3  37.9  240   8  4   6.8   3.7
 12500   4.1  39.4  265   9  5   8.3   4.5 |   4.3  39.7  240   8  4   6.7   3.7
 12000   5.2  41.4  265   9  5   8.1   4.4 |   5.2  41.4  235   9  5   6.5   3.6
 11500   6.4  43.5  260   9  5   8.2   4.5 |   6.2  43.2  235   9  5   6.7   3.7
 11000   7.6  45.7  260   9  4   8.3   4.6 |   7.1  44.8  235   9  5   7.2   4.0
 10500   8.9  48.0  255   8  4   4.8   2.6 |   8.1  46.6  235   8  4   4.3   2.4
 10250   9.1  48.4  250   8  4   5.5   3.0 |   8.3  46.9  235   8  4   6.8   3.7
 10000   9.8  49.6  250   8  4  10.7   5.9 |   9.2  48.6  235   8  4  12.5   6.9
  9750  10.5  50.9  245   8  4   9.6   5.3 |  10.0  50.0  235   8  4  11.3   6.2
  9500  11.2  52.2  245   8  4   8.6   4.7 |  10.8  51.4  240   8  4  10.5   5.7
  9250  11.7  53.1  240   7  4   6.9   3.8 |  11.5  52.7  235   8  4   9.2   5.0
  9000  12.3  54.1  240   7  4   7.8   4.3 |  12.2  54.0  240   8  4  10.3   5.6
  8750  12.9  55.2  235   7  4   8.3   4.6 |  13.0  55.4  240   8  4  10.7   5.9
  8500  13.5  56.3  230   7  4   7.7   4.2 |  13.8  56.8  240   8  4  10.3   5.7
  8250  14.0  57.2  230   7  4   7.2   3.9 |  14.5  58.1  240   8  4  10.1   5.5
  8000  14.5  58.1  225   7  4   7.3   4.0 |  15.2  59.4  240   8  4   9.9   5.5
  7750  15.0  59.0  220   7  4   7.3   4.0 |  16.0  60.8  240   8  4   9.8   5.4
  7500  15.6  60.1  215   7  4   7.0   3.9 |  16.7  62.1  240   8  4  10.0   5.5
  7250  16.1  61.0  210   7  4   6.9   3.8 |  17.5  63.5  240   8  4  10.1   5.5
  7000  16.5  61.7  205   8  4   6.7   3.7 |  18.2  64.8  240   8  4  10.1   5.5
  6750  17.0  62.6  200   8  4   6.4   3.5 |  19.0  66.2  240   8  4  10.5   5.7
  6500  17.5  63.5  195   8  4   6.2   3.4 |  19.8  67.6  240   7  4  10.8   5.9
  6250  17.9  64.2  190   7  4   6.5   3.6 |  20.6  69.1  240   7  4  11.4   6.3
  6000  18.3  64.9  185   7  4   5.5   3.0 |  21.4  70.5  240   7  4   9.7   5.3
  5750  18.6  65.5  175   7  3   5.5   3.0 |  22.1  71.8  240   7  4  12.1   6.7
  5500  19.1  66.4  175   6  3   6.7   3.7 |  23.2  73.8  240   7  4  16.3   9.0
  5250  19.5  67.1  175   6  3   5.7   3.1 |  24.3  75.7  240   7  4  13.1   7.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/07/2015 at 1500 MDT          |       07/07/2015 at 1800 MDT
                                           |
K index... +30.7  LI... +271.3             | K index... +29.8  LI... +269.9
CAPE... +284.6  CIN... -26.5               | CAPE... +702.3  CIN... -21.7
                                           |
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 -62.1 -79.8  240  24 12   1.9   1.1 | -62.5 -80.5  245  22 11   1.7   1.0
 45000 -59.1 -74.4  235  28 14   1.9   1.1 | -59.3 -74.7  230  24 12   3.0   1.6
 40000 -55.4 -67.7  210  26 13   8.4   4.6 | -54.3 -65.7  190  24 13   7.7   4.2
 38000 -50.4 -58.7  210  28 15   8.3   4.6 | -49.8 -57.6  195  24 12   7.6   4.1
 36000 -45.4 -49.7  210  31 16   8.3   4.5 | -45.2 -49.4  205  24 12   7.5   4.1
 34000 -39.5 -39.1  210  27 14   8.9   4.9 | -40.1 -40.2  210  21 11   8.7   4.8
 32000 -34.1 -29.4  210  23 12   8.8   4.8 | -34.2 -29.6  215  16  8   8.6   4.7
 30000 -29.3 -20.7  210  18  9   8.0   4.4 | -29.5 -21.1  220  13  7   7.9   4.3
 29000 -26.9 -16.4  215  16  8   8.0   4.4 | -27.1 -16.8  225  12  6   7.9   4.3
 28000 -24.6 -12.3  215  14  7   7.5   4.1 | -24.8 -12.6  230  11  6   7.5   4.1
 27000 -22.5  -8.5  215  13  7   7.1   3.9 | -22.7  -8.9  235  10  5   7.1   3.9
 26000 -20.4  -4.7  215  12  6   7.1   3.9 | -20.6  -5.1  240  10  5   7.1   3.9
 25000 -18.3  -0.9  220  11  6   7.2   3.9 | -18.5  -1.3  240   9  5   7.2   4.0
 24000 -16.3   2.7  220  10  5   6.5   3.6 | -16.4   2.5  250   9  4   6.8   3.7
 23000 -14.4   6.1  225  10  5   6.5   3.6 | -14.4   6.1  260   9  4   6.8   3.7
 22000 -12.5   9.5  230  10  5   6.6   3.6 | -12.5   9.5  265   9  5   6.9   3.8
 21000 -10.7  12.7  230   9  5   6.1   3.4 | -10.7  12.7  270   9  5   5.9   3.2
 20000  -8.9  16.0  235   9  4   6.2   3.4 |  -9.0  15.8  265   9  5   5.9   3.2
 19500  -8.0  17.6  240   8  4   6.2   3.4 |  -8.1  17.4  265   9  5   5.9   3.2
 19000  -7.1  19.2  240   8  4   5.9   3.2 |  -7.3  18.9  265   9  5   5.5   3.0
 18500  -6.3  20.7  245   8  4   5.7   3.1 |  -6.5  20.3  265   9  5   5.2   2.9
 18000  -5.5  22.1  245   8  4   5.7   3.1 |  -5.8  21.6  265   9  5   5.2   2.8
 17500  -4.7  23.5  245   8  4   5.5   3.0 |  -5.0  23.0  265  10  5   5.4   3.0
 17000  -3.9  25.0  245   8  4   5.5   3.0 |  -4.2  24.4  265  10  5   5.4   3.0
 16500  -3.1  26.4  245   8  4   5.6   3.1 |  -3.4  25.9  265  11  6   5.9   3.2
 16000  -2.3  27.9  250   8  4   5.6   3.1 |  -2.5  27.5  265  11  6   6.1   3.4
 15500  -1.1  30.0  250   8  4   4.7   2.6 |  -1.1  30.0  265  12  6   6.6   3.6
 15000  -0.5  31.1  255   8  4   4.6   2.5 |  -0.1  31.8  265  12  6   6.7   3.7
 14500   0.2  32.4  255   8  4   5.7   3.2 |   0.8  33.4  260  13  7   7.1   3.9
 14000   1.2  34.2  255   8  4   6.6   3.6 |   1.9  35.4  260  13  7   7.6   4.2
 13500   2.1  35.8  255   8  4   7.3   4.0 |   3.1  37.6  255  14  7   7.7   4.2
 13000   3.4  38.1  255   8  4   8.7   4.8 |   4.2  39.6  255  14  7   7.9   4.3
 12500   4.6  40.3  255   8  4   8.5   4.7 |   5.3  41.5  250  14  7   7.9   4.4
 12000   5.7  42.3  255   9  4   7.2   4.0 |   6.5  43.7  250  13  7   8.2   4.5
 11500   6.8  44.2  255   9  5   7.3   4.0 |   7.6  45.7  250  13  6   8.3   4.5
 11000   7.9  46.2  250   9  5   7.5   4.1 |   8.7  47.7  250  12  6   7.5   4.1
 10500   9.0  48.2  250   9  5   4.3   2.4 |   9.7  49.5  250  11  6  10.3   5.7
 10250   9.1  48.4  250   9  5   4.7   2.6 |  10.6  51.1  250  10  5  11.2   6.1
 10000   9.7  49.5  245   9  4   9.3   5.1 |  11.2  52.2  250  10  5   8.0   4.4
  9750  10.3  50.5  245   8  4   8.2   4.5 |  11.8  53.2  250   9  5   9.0   4.9
  9500  10.9  51.6  245   8  4   7.9   4.3 |  12.5  54.5  245   9  5   8.5   4.7
  9250  11.4  52.5  245   8  4   6.8   3.7 |  13.0  55.4  245   8  4   8.1   4.5
  9000  11.9  53.4  245   8  4   7.2   4.0 |  13.6  56.5  245   8  4   8.4   4.6
  8750  12.4  54.3  245   8  4   7.8   4.3 |  14.3  57.7  245   7  4   8.7   4.8
  8500  13.0  55.4  245   8  4   7.4   4.1 |  14.9  58.8  240   6  3   8.4   4.6
  8250  13.5  56.3  245   8  4   7.1   3.9 |  15.5  59.9  235   6  3   7.8   4.3
  8000  14.0  57.2  245   8  4   7.0   3.9 |  16.0  60.8  230   5  3   7.3   4.0
  7750  14.5  58.1  245   7  4   6.9   3.8 |  16.5  61.7  225   4  2   7.2   3.9
  7500  15.0  59.0  245   7  4   7.2   4.0 |  17.1  62.8  220   4  2   7.1   3.9
  7250  15.5  59.9  245   7  4   7.6   4.2 |  17.6  63.7  210   3  2   7.0   3.8
  7000  16.1  61.0  245   7  3   7.3   4.0 |  18.1  64.6  200   3  1   7.1   3.9
  6750  16.6  61.9  245   7  3   7.6   4.2 |  18.5  65.3  190   2  1   7.2   3.9
  6500  17.2  63.0  245   7  3   9.1   5.0 |  19.1  66.4  185   2  1   9.1   5.0
  6250  17.9  64.2  245   6  3   9.9   5.4 |  19.8  67.6  185   2  1  10.6   5.8
  6000  18.6  65.5  240   6  3   9.4   5.2 |  20.6  69.1  185   2  1  10.1   5.5
  5750  19.3  66.7  240   6  3   9.3   5.1 |  21.3  70.3  185   2  1  10.0   5.5
  5500  20.0  68.0  240   6  3   9.5   5.2 |  22.0  71.6  190   2  1   9.9   5.4
  5250  20.7  69.3  245   6  3   9.4   5.2 |  22.8  73.0  195   2  1  10.0   5.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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 at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  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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