Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 021453
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0853 MDT Sunday, August 2, 2015

This forecast is for Sunday, August 2, 2015:

If the trigger temperature of 81.0 F/27.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 308 ft/min (1.6 m/s)
   Maximum height of thermals.................. 11557 ft MSL (6718 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8293 ft MSL (3453 ft AGL)
Thermal soaring outlook for Monday 08/03....... Good

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

Remarks...

Sunrise/Sunset.................... 06:15:22 / 20:25:45 MDT
Total possible sunshine........... 14 hr 10 min 23 sec (850 min 23 sec)
Altitude of sun at 13:20:19 MDT... 68.55 degrees

Upper air data from rawinsonde observation taken on 08/02/2015 at 0600 MDT

Freezing level.................. 15646 ft MSL (10807 ft AGL)
Convective condensation level... 14889 ft MSL (10050 ft AGL)
Lifted condensation level....... 14110 ft MSL (9271 ft AGL)
Lifted index.................... +0.9
K index......................... +25.9

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  -68.3 -90.9   285   35   18   7.3   4.0   79.7 175.5    28.9      M    M
 45000  -62.0 -79.6   250   54   28   4.3   2.4   65.7 150.3    22.3      M    M
 40000  -53.1 -63.6   240   59   30   5.3   2.9   56.9 134.5    18.0      M    M
 38000  -48.0 -54.4   240   52   27   5.4   3.0   54.6 130.3    16.9      M    M
 36000  -42.6 -44.7   240   46   24   8.9   4.9   54.0 129.2    16.9      M    M
 34000  -37.5 -35.5   250   35   18   7.1   3.9   52.9 127.2    16.5      M    M
 32000  -32.3 -26.1   265   26   13   7.7   4.2   52.1 125.7    16.3      M    M
 30000  -28.3 -18.9   260   15    8   5.1   2.8   49.7 121.4    14.8      M    M
 29000  -26.1 -15.0   265   11    6   7.9   4.4   48.6 119.5    14.2      M    M
 28000  -23.7 -10.7   275    7    4   8.8   4.8   48.0 118.5    13.9      M    M
 27000  -21.5  -6.7   290    5    3   7.1   3.9   47.1 116.8    13.3      M    M
 26000  -19.2  -2.6   315    4    2   8.0   4.4   46.3 115.4    12.8      M    M
 25000  -16.9   1.6   350    4    2   6.9   3.8   45.7 114.3    12.4      M    M
 24000  -15.1   4.8   350    3    2   6.0   3.3   44.4 111.9    11.4      M    M
 23000  -12.4   9.7   355    2    1   8.9   4.9   44.1 111.3    11.2      M    M
 22000  -10.3  13.5   005    1    1   6.8   3.7   43.1 109.6    10.6      M    M
 21000  -10.7  12.7   120   11    5  -2.8  -1.5   39.3 102.8     7.4      M    M
 20000   -8.4  16.9   125   16    8   7.7   4.2   37.8 100.0     6.1      M    M
 19500   -7.3  18.9   110   15    8   9.1   5.0   37.4  99.4     5.8      M    M
 19000   -6.3  20.7   100   16    8   2.4   1.3   36.8  98.3     5.3      M    M
 18500   -5.9  21.4   090   17    9   2.7   1.5   35.6  96.1     4.3      M    M
 18000   -5.0  23.0   080   19   10   8.1   4.4   34.9  94.8     3.8      M    M
 17500   -3.9  25.0   080   16    8   8.1   4.5   34.6  94.2     3.4      M    M
 17000   -2.8  27.0   080   14    7   7.3   4.0   34.3  93.7     3.0      M    M
 16500   -1.8  28.8   080   12    6   7.0   3.8   33.8  92.8     2.6      M    M
 16000   -0.8  30.6   080   10    5   8.2   4.5   33.3  92.0     2.1      M    M
 15500    0.5  32.9   090    9    5   8.9   4.9   33.2  91.8     2.0      M    M
 15000    1.9  35.4   095    9    4   9.0   4.9   33.1  91.5     1.9      M    M
 14500    3.2  37.8   105    8    4   9.0   4.9   33.0  91.4     1.8      M    M
 14000    4.6  40.3   115    8    4   9.0   4.9   32.9  91.2     1.7      M    M
 13500    5.9  42.6   125    9    5   9.0   4.9   32.7  90.9     1.6      M    M
 13000    7.2  45.0   130   10    5   8.9   4.9   32.6  90.7     1.4      M    M
 12500    8.6  47.5   135   12    6   7.3   4.0   32.5  90.5     1.3      M    M
 12000    9.3  48.7   140   13    7   5.3   2.9   31.8  89.2     0.6      M    M
 11500   10.1  50.2   150   12    6   5.1   2.8   31.0  87.9    -0.1    504  2.6
 11000   11.0  51.8   155   11    6   7.4   4.1   30.5  86.9    -0.7    462  2.3
 10500   12.0  53.6   165   10    5   7.6   4.2   30.1  86.1    -1.1    417  2.1
 10250   12.6  54.7   170   10    5   8.6   4.7   29.9  85.9    -1.2    392  2.0
 10000   13.2  55.8   170   10    5   8.9   4.9   29.9  85.8    -1.3    365  1.9
  9750   13.9  57.0   170   10    5   9.0   4.9   29.8  85.7    -1.4    337  1.7
  9500   14.5  58.1   165   10    5   8.5   4.7   29.7  85.5    -1.5    310  1.6
  9250   15.0  59.0   165   10    5   2.4   1.3   29.5  85.1    -1.7    289  1.5
  9000   15.0  59.0   165   10    5   2.7   1.5   28.8  83.8    -2.5    282  1.4
  8750   15.5  59.9   165   10    5   8.3   4.5   28.5  83.3    -2.7    260  1.3
  8500   16.1  61.0   160   10    5   8.2   4.5   28.4  83.1    -2.9    235  1.2
  8250   16.7  62.1   160   10    5   8.2   4.5   28.3  82.9    -3.0    209  1.1
  8000   17.3  63.1   155   10    5   8.2   4.5   28.2  82.7    -3.1    184  0.9
  7750   17.9  64.2   160   11    6   8.2   4.5   28.0  82.5    -3.3    158  0.8
  7500   18.5  65.3   165   13    7   8.1   4.5   27.9  82.2    -3.4    133  0.7
  7250   19.1  66.4   170   15    8   8.4   4.6   27.8  82.0    -3.5    107  0.5
  7000   19.6  67.3   175   17    9   4.0   2.2   27.6  81.7    -3.7     84  0.4
  6750   19.7  67.5   175   16    8   1.0   0.6   26.9  80.5    -4.4     74  0.4
  6500   20.0  68.0   175   15    8   6.3   3.4   26.5  79.6    -4.9     59  0.3
  6250   20.6  69.1   170   14    7   8.9   4.9   26.3  79.4    -5.0     34  0.2
  6000   21.2  70.2   170   13    7   7.8   4.3   26.2  79.2    -5.2      8  0.0
  5750   21.8  71.2   165   11    6   9.5   5.2   26.1  79.0    -5.3      M    M
  5500   22.3  72.1   150   10    5   3.6   2.0   26.0  78.8    -5.4      M    M
  5250   22.2  72.0   135    8    4  -3.3  -1.8   25.2  77.3    -6.4      M    M
  5000   22.1  71.8   115    8    4   5.0   2.8   24.4  76.0    -7.2      M    M

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

           08/02/2015 at 0900 MDT          |       08/02/2015 at 1200 MDT
                                           |
K index... +26.2  LI... +270.8             | K index... +25.0  LI... +269.8
CAPE... +191.5  CIN... -90.6               | CAPE... +500.7  CIN... -6.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -66.0 -86.8  275  29 15   2.0   1.1 | -65.8 -86.4  275  23 12   2.5   1.4
 45000 -61.2 -78.2  265  43 22   5.8   3.2 | -61.0 -77.8  260  34 18   4.6   2.5
 40000 -51.7 -61.1  240  51 26   7.1   3.9 | -52.7 -62.9  230  46 23   8.7   4.8
 38000 -47.5 -53.5  235  38 20   7.1   3.9 | -47.6 -53.7  225  37 19   8.6   4.7
 36000 -43.2 -45.8  225  27 14   7.6   4.2 | -42.4 -44.3  215  29 15   8.5   4.7
 34000 -38.1 -36.6  235  22 11   8.5   4.7 | -37.4 -35.3  220  21 11   8.4   4.6
 32000 -33.0 -27.4  250  18  9   8.4   4.6 | -32.3 -26.1  225  12  6   9.3   5.1
 30000 -28.5 -19.3  255  12  6   7.6   4.1 | -27.6 -17.7  200   9  5   8.0   4.4
 29000 -26.2 -15.2  260   9  5   7.6   4.2 | -25.2 -13.4  185   9  5   8.0   4.4
 28000 -24.0 -11.2  265   6  3   7.2   3.9 | -22.4  -8.3  165   9  5   6.5   3.5
 27000 -22.0  -7.6  260   4  2   6.9   3.8 | -20.4  -4.7  155   8  4   6.6   3.6
 26000 -19.4  -2.9  205   1  0   6.9   3.8 | -18.5  -1.3  140   7  3   6.6   3.6
 25000 -17.4   0.7  110   2  1   6.8   3.7 | -16.5   2.3  125   6  3   6.3   3.5
 24000 -15.4   4.3  110   4  2   6.7   3.7 | -14.8   5.4  115   8  4   6.0   3.3
 23000 -13.5   7.7  110   7  3   6.7   3.7 | -13.0   8.6  110   9  5   6.0   3.3
 22000 -11.5  11.3  110   9  4   6.1   3.3 | -11.3  11.7  105  10  5   5.8   3.2
 21000  -9.9  14.2  110  11  6   5.5   3.0 |  -9.7  14.5  100  13  7   5.5   3.0
 20000  -8.4  16.9  110  14  7   5.5   3.0 |  -8.1  17.4  100  16  8   5.5   3.0
 19500  -7.6  18.3  110  15  8   5.5   3.0 |  -7.3  18.9  100  17  9   5.5   3.0
 19000  -6.7  19.9  105  16  8   6.3   3.5 |  -6.4  20.5  095  18  9   6.2   3.4
 18500  -5.8  21.6  105  16  8   6.3   3.4 |  -5.5  22.1  090  20 10   6.2   3.4
 18000  -4.9  23.2  100  17  9   6.7   3.7 |  -4.6  23.7  085  21 11   6.3   3.5
 17500  -3.9  25.0  100  17  9   7.1   3.9 |  -3.6  25.5  085  21 11   6.5   3.6
 17000  -2.9  26.8  095  17  9   7.1   3.9 |  -2.6  27.3  080  22 11   6.5   3.6
 16500  -1.7  28.9  090  17  9   8.3   4.5 |  -1.6  29.1  080  22 11   7.6   4.2
 16000  -0.5  31.1  090  16  8   8.2   4.5 |  -0.4  31.3  075  21 11   7.5   4.1
 15500   0.7  33.3  085  16  8   8.4   4.6 |   0.7  33.3  075  20 11   7.9   4.3
 15000   2.0  35.6  085  15  8   8.5   4.7 |   1.9  35.4  070  20 10   8.0   4.4
 14500   3.3  37.9  080  15  8   8.2   4.5 |   3.0  37.4  070  19 10   7.8   4.3
 14000   4.4  39.9  080  13  7   7.6   4.2 |   4.0  39.2  070  17  9   7.2   3.9
 13500   5.4  41.7  085  12  6   7.6   4.2 |   5.4  41.7  075  14  7   6.1   3.3
 13000   6.8  44.2  090   9  4   6.4   3.5 |   6.2  43.2  080  12  6   5.7   3.1
 12500   7.7  45.9  095   6  3   6.4   3.5 |   6.9  44.4  090   9  5   5.8   3.2
 12000   8.6  47.5  110   5  3   6.4   3.5 |   7.8  46.0  105   8  4   5.9   3.2
 11500   9.5  49.1  130   4  2   6.6   3.6 |   8.6  47.5  125   7  3   5.9   3.2
 11000  10.4  50.7  145   3  2   6.6   3.6 |   9.4  48.9  145   5  3   5.7   3.1
 10500  11.4  52.5  165   3  1   3.5   1.9 |  10.2  50.4  180   5  3   3.4   1.9
 10250  11.5  52.7  175   3  1   4.3   2.4 |  10.4  50.7  190   5  3   5.5   3.0
 10000  12.1  53.8  180   3  1   9.0   4.9 |  11.0  51.8  200   6  3   9.9   5.4
  9750  12.6  54.7  190   3  2   8.1   4.4 |  11.6  52.9  205   7  3   9.1   5.0
  9500  13.2  55.8  195   3  2   7.0   3.9 |  12.2  54.0  210   7  4   8.2   4.5
  9250  13.6  56.5  195   4  2   6.0   3.3 |  12.8  55.0  210   8  4   8.3   4.5
  9000  14.1  57.4  190   4  2   7.1   3.9 |  13.5  56.3  210   8  4  10.4   5.7
  8750  14.6  58.3  190   5  3   7.4   4.1 |  14.2  57.6  210   8  4  10.5   5.8
  8500  15.1  59.2  190   6  3   6.7   3.7 |  15.0  59.0  210   9  4   9.8   5.4
  8250  15.5  59.9  185   6  3   6.0   3.3 |  15.6  60.1  210   9  4   9.1   5.0
  8000  15.9  60.6  185   7  3   6.6   3.6 |  16.3  61.3  210   9  5   9.8   5.4
  7750  16.4  61.5  180   7  4   6.7   3.7 |  17.1  62.8  210   9  5  10.1   5.6
  7500  16.9  62.4  180   8  4   5.5   3.0 |  17.8  64.0  210   9  5  10.1   5.6
  7250  17.3  63.1  175   8  4   4.8   2.7 |  18.6  65.5  210   9  5  10.2   5.6
  7000  17.6  63.7  170   8  4   5.0   2.7 |  19.3  66.7  210   9  5  10.1   5.5
  6750  18.0  64.4  165   7  4   5.0   2.8 |  20.1  68.2  210   9  5  10.3   5.7
  6500  18.4  65.1  160   7  3   5.2   2.8 |  20.9  69.6  215   9  5  10.7   5.9
  6250  18.8  65.8  155   6  3   5.5   3.0 |  21.7  71.1  215   9  5  10.9   6.0
  6000  19.2  66.6  145   5  3   4.5   2.5 |  22.5  72.5  215   9  5  10.2   5.6
  5750  19.5  67.1  140   4  2   7.4   4.0 |  23.2  73.8  215   9  4  12.0   6.6
  5500  20.2  68.4  135   4  2  11.1   6.1 |  24.2  75.6  215   9  4  14.5   8.0
  5250  21.0  69.8  135   4  2   8.2   4.5 |  25.2  77.4  215   8  4  12.6   6.9
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/02/2015 at 1500 MDT          |       08/02/2015 at 1800 MDT
                                           |
K index... +28.2  LI... +270.9             | K index... +29.6  LI... +271.6
CAPE... +200.7  CIN... -64.7               | CAPE... +104.0  CIN... -36.0
                                           |
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 -66.0 -86.8  265  22 11   2.6   1.4 | -66.0 -86.8  255  27 14   2.3   1.3
 45000 -61.0 -77.8  250  28 14   4.7   2.6 | -61.0 -77.8  235  35 18   5.4   3.0
 40000 -52.5 -62.5  225  27 14   9.2   5.0 | -51.7 -61.1  215  35 18   8.6   4.7
 38000 -47.0 -52.6  210  24 13   9.2   5.0 | -46.5 -51.7  215  33 17   8.6   4.7
 36000 -41.4 -42.5  200  23 12   9.0   5.0 | -41.3 -42.3  215  32 16   8.5   4.7
 34000 -36.1 -33.0  195  22 11   8.9   4.9 | -36.3 -33.3  220  28 15   8.5   4.7
 32000 -30.8 -23.4  185  22 11  10.1   5.5 | -31.2 -24.2  220  25 13   9.5   5.2
 30000 -26.3 -15.3  180  21 11   7.4   4.1 | -26.6 -15.9  220  22 11   7.6   4.2
 29000 -23.5 -10.3  170  20 11   7.4   4.1 | -24.4 -11.9  220  21 11   7.6   4.2
 28000 -21.4  -6.5  165  20 10   6.5   3.5 | -21.6  -6.9  220  19 10   7.0   3.8
 27000 -19.5  -3.1  160  19 10   6.6   3.6 | -19.6  -3.3  220  18  9   7.1   3.9
 26000 -17.6   0.3  155  18  9   6.6   3.6 | -17.5   0.5  215  17  9   7.1   3.9
 25000 -15.7   3.7  150  18  9   6.3   3.5 | -15.4   4.3  215  17  9   6.6   3.6
 24000 -13.9   7.0  145  19 10   6.0   3.3 | -13.7   7.3  210  15  7   5.9   3.3
 23000 -12.2  10.0  135  19 10   6.0   3.3 | -12.0  10.4  205  13  7   5.9   3.3
 22000 -10.4  13.3  130  21 11   5.8   3.2 | -10.2  13.6  190  11  6   5.9   3.2
 21000  -8.8  16.2  125  21 11   5.5   3.0 |  -8.6  16.5  175  12  6   5.8   3.2
 20000  -7.2  19.0  115  22 12   5.5   3.0 |  -6.9  19.6  160  13  7   5.8   3.2
 19500  -6.4  20.5  115  23 12   5.5   3.0 |  -6.1  21.0  150  14  7   5.9   3.2
 19000  -5.7  21.7  110  24 12   5.3   2.9 |  -5.3  22.5  145  15  8   4.9   2.7
 18500  -4.9  23.2  105  24 12   5.4   2.9 |  -4.6  23.7  140  17  9   4.9   2.7
 18000  -4.1  24.6  105  25 13   5.3   2.9 |  -3.9  25.0  135  18  9   4.9   2.7
 17500  -3.4  25.9  100  25 13   5.2   2.8 |  -3.2  26.2  130  18  9   4.8   2.6
 17000  -2.6  27.3  100  25 13   5.3   2.9 |  -2.5  27.5  125  18  9   4.7   2.6
 16500  -1.9  28.6  095  25 13   4.3   2.3 |  -1.8  28.8  120  18  9   5.5   3.0
 16000  -1.3  29.7  095  24 12   4.4   2.4 |  -1.0  30.2  120  17  9   5.5   3.0
 15500  -0.6  30.9  095  23 12   6.3   3.4 |  -0.2  31.6  115  16  8   6.1   3.3
 15000   0.5  32.9  095  22 11   7.2   4.0 |   0.7  33.3  110  16  8   6.5   3.5
 14500   1.5  34.7  095  20 10   8.1   4.5 |   1.7  35.1  105  15  8   6.8   3.7
 14000   3.0  37.4  095  18  9  10.2   5.6 |   2.8  37.0  105  15  7   7.8   4.3
 13500   5.2  41.4  095  15  8   8.8   4.8 |   4.5  40.1  100  14  7   7.7   4.2
 13000   6.4  43.5  095  13  7   8.1   4.4 |   5.6  42.1  100  14  7   7.7   4.2
 12500   7.6  45.7  090  11  6   7.5   4.1 |   6.7  44.1  100  14  7   7.8   4.3
 12000   8.5  47.3  100  10  5   7.0   3.8 |   7.9  46.2  100  14  7   8.0   4.4
 11500   9.5  49.1  110   8  4   6.8   3.7 |   9.1  48.4  100  13  7   7.9   4.4
 11000  10.5  50.9  135   7  3   6.3   3.4 |  10.2  50.4  100  13  7   7.5   4.1
 10500  11.4  52.5  165   7  4   3.9   2.1 |  11.4  52.5  100  13  7   5.2   2.9
 10250  11.6  52.9  180   6  3   4.1   2.2 |  11.7  53.1  105  12  6   6.2   3.4
 10000  12.0  53.6  195   6  3   7.4   4.1 |  12.3  54.1  105  12  6   9.9   5.4
  9750  12.5  54.5  210   6  3   6.8   3.7 |  13.0  55.4  110  11  6   9.4   5.1
  9500  12.9  55.2  220   7  4   6.2   3.4 |  13.7  56.7  110  11  6   7.8   4.3
  9250  13.3  55.9  230   7  4   6.8   3.7 |  14.1  57.4  115  10  5   6.0   3.3
  9000  13.8  56.8  240   7  4   8.9   4.9 |  14.6  58.3  115  10  5   7.0   3.9
  8750  14.4  57.9  245   7  4   9.0   4.9 |  15.1  59.2  115   9  4   7.2   4.0
  8500  15.0  59.0  250   7  4   9.6   5.3 |  15.6  60.1  115   8  4   7.0   3.8
  8250  15.8  60.4  250   7  4  10.2   5.6 |  16.0  60.8  115   6  3   6.8   3.7
  8000  16.5  61.7  250   8  4   9.9   5.4 |  16.5  61.7  120   5  3   8.0   4.4
  7750  17.2  63.0  250   8  4   9.8   5.4 |  17.1  62.8  120   4  2   8.9   4.9
  7500  17.9  64.2  250   8  4   9.7   5.3 |  17.7  63.9  120   4  2   9.3   5.1
  7250  18.7  65.7  250   8  4   9.6   5.3 |  18.4  65.1  120   3  2   9.8   5.4
  7000  19.4  66.9  250   8  4   9.8   5.4 |  19.1  66.4  125   3  2   9.6   5.3
  6750  20.1  68.2  250   8  4  10.2   5.6 |  19.9  67.8  125   3  2  10.0   5.5
  6500  20.9  69.6  250   8  4  10.4   5.7 |  20.6  69.1  125   3  1  10.6   5.8
  6250  21.7  71.1  250   8  4  10.8   5.9 |  21.4  70.5  125   3  1  11.3   6.2
  6000  22.4  72.3  250   7  4   9.7   5.3 |  22.2  72.0  125   3  1   9.7   5.3
  5750  23.1  73.6  250   7  4   9.9   5.4 |  22.9  73.2  130   2  1   9.8   5.4
  5500  23.9  75.0  250   7  4  11.4   6.3 |  23.7  74.7  130   2  1  11.9   6.5
  5250  24.7  76.5  250   7  4  10.1   5.6 |  24.6  76.3  125   2  1  10.4   5.7
  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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