Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221239
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0639 MDT Tuesday, July 22, 2014

This forecast is for Tuesday, July 22, 2014:

If the trigger temperature of 89.2 F/31.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1453 ft/min (7.4 m/s)
   Maximum height of thermals.................. 20193 ft MSL (15354 ft AGL)

Forecast maximum temperature................... 100.0 F/38.2 C
Time of trigger temperature.................... 1045 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................. 14756 ft MSL (9917 ft AGL)
Thermal soaring outlook for Wednesday 07/23.... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:06:06 / 20:35:16 MDT
Total possible sunshine........... 14 hr 29 min 10 sec (869 min 10 sec)
Altitude of sun at 13:20:33 MDT... 71.03 degrees

Upper air data from rawinsonde observation taken on 07/22/2014 at 0600 MDT

Freezing level.................. 16680 ft MSL (11841 ft AGL)
Convective condensation level... 21968 ft MSL (17129 ft AGL)
Lifted condensation level....... 21686 ft MSL (16847 ft AGL)
Lifted index.................... +1.5
K index......................... +5.4

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  -70.3 -94.5   230   33   17  -1.8  -1.0   76.6 170.0    22.5      M    M
 45000  -60.5 -76.9   245   60   31   6.3   3.5   67.3 153.2    18.5      M    M
 40000  -50.4 -58.7   240   68   35   7.1   3.9   60.1 140.3    14.9      M    M
 38000  -46.2 -51.2   245   60   31   7.1   3.9   57.8 136.0    13.7      M    M
 36000  -42.5 -44.5   250   52   27   3.9   2.1   54.9 130.8    12.0      M    M
 34000  -38.8 -37.8   250   45   23   6.4   3.5   51.8 125.3    10.1      M    M
 32000  -34.5 -30.1   245   36   18   5.7   3.2   48.8 119.9     8.2      M    M
 30000  -30.3 -22.5   240   27   14   8.0   4.4   46.6 115.9     6.7      M    M
 29000  -27.9 -18.2   260   26   13   8.0   4.4   45.9 114.6     6.2      M    M
 28000  -25.5 -13.9   275   27   14   8.1   4.4   45.2 113.4     5.8      M    M
 27000  -23.1  -9.6   270   27   14   4.6   2.5   44.5 112.2     5.3      M    M
 26000  -21.6  -6.9   270   27   14   8.0   4.4   42.7 108.9     3.9      M    M
 25000  -19.2  -2.6   265   27   14   8.5   4.7   42.1 107.9     3.5      M    M
 24000  -16.6   2.1   260   25   13   8.8   4.8   41.7 107.1     3.2      M    M
 23000  -14.0   6.8   250   24   12   9.3   5.1   41.4 106.5     2.9      M    M
 22000  -12.6   9.3   230   17    9   2.8   1.5   39.5 103.1     1.4      M    M
 21000  -10.3  13.5   235   15    8   9.2   5.1   38.8 101.9     0.8      M    M
 20000   -8.3  17.1   245   14    7   3.6   2.0   37.8 100.0    -0.2   1446  7.3
 19500   -7.4  18.7   275   14    7   8.7   4.8   37.2  98.9    -0.8   1405  7.1
 19000   -6.2  20.8   275   13    7   7.5   4.1   36.8  98.3    -1.0   1355  6.9
 18500   -5.0  23.0   265   12    6   8.6   4.7   36.5  97.7    -1.3   1304  6.6
 18000   -3.1  26.4   255   11    6   8.6   4.7   36.3  97.3    -1.5   1224  6.2
 17500   -1.8  28.8   260   12    6   8.6   4.7   36.0  96.9    -1.8   1171  5.9
 17000   -0.6  30.9   265   12    6   8.6   4.7   35.8  96.5    -2.0   1118  5.7
 16500    0.7  33.3   265   13    6   8.6   4.7   35.7  96.2    -2.1   1064  5.4
 16000    2.0  35.6   270   13    7   8.7   4.8   35.5  95.9    -2.3   1011  5.1
 15500    3.3  37.9   265   14    7   8.8   4.9   35.3  95.5    -2.5    958  4.9
 15000    4.4  39.9   260   15    8   6.8   3.7   35.0  95.0    -2.8    908  4.6
 14500    5.5  41.9   250   12    6   6.9   3.8   34.5  94.1    -3.3    863  4.4
 14000    6.5  43.7   235   10    5   6.6   3.6   34.1  93.3    -3.8    818  4.2
 13500    7.6  45.7   255   11    6   9.5   5.2   33.8  92.8    -4.1    768  3.9
 13000    9.0  48.2   265   12    6   9.3   5.1   33.7  92.7    -4.2    712  3.6
 12500   10.4  50.7   260   13    7   9.3   5.1   33.6  92.6    -4.3    657  3.3
 12000   11.7  53.1   255   14    7   9.3   5.1   33.6  92.4    -4.4    601  3.1
 11500   13.1  55.6   275   13    7   9.3   5.1   33.5  92.3    -4.5    545  2.8
 11000   14.5  58.1   290   14    7   9.3   5.1   33.4  92.1    -4.6    490  2.5
 10500   15.8  60.4   285   15    7   8.3   4.6   33.3  91.9    -4.8    435  2.2
 10250   16.4  61.5   285   13    7   7.8   4.3   33.1  91.6    -5.0    410  2.1
 10000   17.0  62.6   285   12    6   8.0   4.4   33.0  91.4    -5.1    384  2.0
  9750   17.6  63.7   285   10    5   7.9   4.4   32.9  91.1    -5.3    359  1.8
  9500   18.2  64.8   285    9    5   7.9   4.4   32.7  90.9    -5.4    334  1.7
  9250   18.8  65.8   280    8    4   7.9   4.4   32.6  90.7    -5.5    309  1.6
  9000   19.4  66.9   280    6    3   7.9   4.4   32.5  90.4    -5.7    284  1.4
  8750   19.9  67.8   270    5    3   7.9   4.4   32.3  90.2    -5.8    259  1.3
  8500   20.5  68.9   260    5    3   7.9   4.4   32.2  89.9    -6.0    234  1.2
  8250   21.1  70.0   245    5    2   7.9   4.4   32.0  89.7    -6.1    208  1.1
  8000   21.7  71.1   230    5    3   8.0   4.4   31.9  89.4    -6.3    183  0.9
  7750   22.3  72.1   215    5    2   7.9   4.3   31.7  89.1    -6.4    158  0.8
  7500   22.9  73.2   195    5    3   8.1   4.4   31.6  88.9    -6.6    133  0.7
  7250   23.5  74.3   185    6    3   7.3   4.0   31.5  88.6    -6.8    108  0.5
  7000   23.9  75.0   170    7    3   3.8   2.1   31.1  88.1    -7.1     88  0.4
  6750   24.2  75.6   165    8    4   5.5   3.0   30.7  87.2    -7.6     73  0.4
  6500   24.4  75.9   160   10    5  -4.8  -2.6   30.2  86.3    -8.1     59  0.3
  6250   23.7  74.7   155   12    6  -5.7  -3.1   28.7  83.7    -9.6     72  0.4
  6000   23.9  75.0   150   13    7   4.6   2.5   28.1  82.6   -10.2     60  0.3
  5750   24.2  75.6   145   12    6   6.1   3.3   27.7  81.9   -10.6     44  0.2
  5500   24.4  75.9   140   10    5  -4.4  -2.4   27.3  81.1   -11.1     28  0.1
  5250   23.3  73.9   135    9    4 -23.3 -12.8   25.4  77.6   -13.0     56  0.3
  5000   21.4  70.5   120    7    4 -20.9 -11.5   22.8  73.1   -15.6    104  0.5

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

           07/22/2014 at 0900 MDT          |       07/22/2014 at 1200 MDT
                                           |
K index... +7.4  LI... +2.9                | K index... +3.3  LI... +2.6
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... -1.0
                                           |
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 -66.3 -87.3  250  36 19   2.1   1.2 | -66.6 -87.9  255  36 19   2.0   1.1
 45000 -60.4 -76.7  250  56 29   6.8   3.7 | -60.9 -77.6  250  57 29   6.7   3.7
 40000 -50.1 -58.2  245  64 33   7.2   3.9 | -50.6 -59.1  245  61 31   7.2   3.9
 38000 -45.8 -50.4  245  58 30   7.2   3.9 | -46.3 -51.3  250  54 28   7.2   3.9
 36000 -41.5 -42.7  245  52 27   6.6   3.6 | -42.0 -43.6  250  48 25   6.9   3.8
 34000 -37.6 -35.7  250  40 21   5.7   3.1 | -37.5 -35.5  245  39 20   6.6   3.6
 32000 -34.2 -29.6  250  29 15   6.3   3.5 | -33.6 -28.5  245  30 16   6.5   3.6
 30000 -30.2 -22.4  255  23 12   6.6   3.6 | -29.8 -21.6  245  22 11   6.3   3.4
 29000 -28.2 -18.8  260  19 10   6.6   3.6 | -27.9 -18.2  245  17  9   6.3   3.5
 28000 -26.1 -15.0  265  18  9   8.1   4.4 | -25.9 -14.6  245  15  8   7.9   4.3
 27000 -23.7 -10.7  265  18  9   8.0   4.4 | -23.5 -10.3  245  14  7   7.9   4.3
 26000 -21.3  -6.3  265  18  9   8.0   4.4 | -21.2  -6.2  250  14  7   7.9   4.3
 25000 -19.0  -2.2  265  18  9   7.4   4.1 | -18.8  -1.8  255  13  7   7.5   4.1
 24000 -16.8   1.8  270  16  8   7.3   4.0 | -16.6   2.1  255  11  6   7.5   4.1
 23000 -14.7   5.5  270  14  7   7.3   4.0 | -14.4   6.1  260  10  5   7.5   4.1
 22000 -12.5   9.5  275  12  6   7.3   4.0 | -12.1  10.2  265   8  4   7.8   4.3
 21000 -10.3  13.5  275  10  5   7.3   4.0 |  -9.8  14.4  275   6  3   7.8   4.3
 20000  -8.2  17.2  270   9  5   7.3   4.0 |  -6.9  19.6  300   4  2   7.8   4.3
 19500  -6.5  20.3  270   8  4   7.6   4.2 |  -5.8  21.6  310   3  2   7.8   4.3
 19000  -5.4  22.3  265   8  4   7.6   4.2 |  -4.6  23.7  315   3  2   7.8   4.3
 18500  -4.3  24.3  260   8  4   7.8   4.3 |  -3.5  25.7  320   3  1   8.0   4.4
 18000  -3.1  26.4  255   8  4   8.3   4.5 |  -2.2  28.0  315   3  1   8.3   4.6
 17500  -1.8  28.8  255   8  4   8.3   4.5 |  -1.0  30.2  305   2  1   8.3   4.6
 17000  -0.6  30.9  250   9  4   8.3   4.5 |   0.3  32.5  295   2  1   8.3   4.6
 16500   0.6  33.1  245   9  4   8.3   4.5 |   1.5  34.7  280   2  1   8.3   4.6
 16000   1.8  35.2  240   9  4   8.4   4.6 |   2.7  36.9  260   2  1   8.1   4.5
 15500   3.0  37.4  240   9  5   8.5   4.6 |   3.9  39.0  240   2  1   8.0   4.4
 15000   4.3  39.7  235   9  5   8.5   4.7 |   5.1  41.2  230   3  1   8.2   4.5
 14500   5.6  42.1  235   9  5   9.0   4.9 |   6.4  43.5  220   3  2   8.6   4.7
 14000   6.9  44.4  235   9  5   9.0   4.9 |   7.6  45.7  215   4  2   8.6   4.7
 13500   8.2  46.8  235   9  5   8.8   4.8 |   8.9  48.0  215   4  2   8.6   4.7
 13000   9.5  49.1  235   8  4   8.8   4.8 |  10.2  50.4  210   4  2   8.6   4.7
 12500  10.8  51.4  240   8  4   8.5   4.7 |  11.4  52.5  210   5  2   8.9   4.9
 12000  12.1  53.8  240   7  4   8.5   4.7 |  12.8  55.0  210   4  2   9.0   4.9
 11500  13.3  55.9  240   6  3   8.1   4.4 |  14.0  57.2  205   4  2   8.4   4.6
 11000  14.5  58.1  235   5  3   8.0   4.4 |  15.3  59.5  205   4  2   8.4   4.6
 10500  15.6  60.1  230   4  2   5.9   3.2 |  16.4  61.5  200   3  2   6.9   3.8
 10250  16.0  60.8  225   4  2   6.9   3.8 |  17.0  62.6  190   3  2   7.9   4.3
 10000  16.6  61.9  220   3  2   9.0   4.9 |  17.6  63.7  185   3  2   9.4   5.1
  9750  17.3  63.1  205   3  2   8.2   4.5 |  18.3  64.9  175   3  2   8.6   4.7
  9500  17.8  64.0  195   3  1   7.1   3.9 |  18.9  66.0  165   3  2   7.4   4.0
  9250  18.3  64.9  180   3  1   6.6   3.6 |  19.4  66.9  160   3  2   7.0   3.8
  9000  18.9  66.0  170   3  1   7.6   4.2 |  19.9  67.8  150   3  2   7.8   4.3
  8750  19.4  66.9  155   3  1   7.6   4.2 |  20.5  68.9  145   3  2   7.7   4.2
  8500  19.9  67.8  145   3  2   6.5   3.6 |  21.1  70.0  140   3  2   7.2   3.9
  8250  20.4  68.7  140   3  2   6.0   3.3 |  21.6  70.9  140   3  2   6.8   3.7
  8000  20.9  69.6  135   4  2   6.6   3.6 |  22.1  71.8  135   3  1   7.9   4.3
  7750  21.3  70.3  135   4  2   5.1   2.8 |  22.7  72.9  135   3  1   9.0   4.9
  7500  21.6  70.9  130   4  2   2.7   1.5 |  23.3  73.9  140   2  1   8.7   4.8
  7250  21.8  71.2  130   4  2   2.4   1.3 |  23.9  75.0  140   2  1   8.8   4.8
  7000  21.9  71.4  130   4  2   2.7   1.5 |  24.5  76.1  145   2  1   8.7   4.8
  6750  22.1  71.8  130   4  2   1.5   0.8 |  25.2  77.4  150   2  1   9.9   5.4
  6500  22.1  71.8  130   4  2   0.7   0.4 |  26.0  78.8  155   2  1  10.9   6.0
  6250  22.1  71.8  125   4  2   0.3   0.2 |  26.8  80.2  160   2  1  10.5   5.8
  6000  22.1  71.8  125   4  2   3.1   1.7 |  27.6  81.7  165   2  1  11.0   6.1
  5750  22.6  72.7  125   4  2  11.9   6.5 |  28.6  83.5  170   2  1  18.3  10.1
  5500  23.7  74.7  125   4  2  18.0   9.8 |  30.3  86.5  170   1  1  28.9  15.9
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/22/2014 at 1500 MDT          |       07/22/2014 at 1800 MDT
                                           |
K index... +1.8  LI... +2.3                | K index... +6.5  LI... +1.9
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -66.6 -87.9  250  36 18   2.2   1.2 | -67.0 -88.6  250  36 19   2.3   1.3
 45000 -60.6 -77.1  255  55 28   6.7   3.7 | -60.9 -77.6  255  53 27   6.7   3.7
 40000 -50.4 -58.7  250  59 31   7.2   4.0 | -50.6 -59.1  250  56 29   7.6   4.2
 38000 -46.0 -50.8  250  52 27   7.2   4.0 | -46.1 -51.0  250  50 26   7.6   4.2
 36000 -41.2 -42.2  250  44 23   6.6   3.6 | -41.0 -41.8  250  43 22   7.0   3.8
 34000 -37.2 -35.0  250  36 19   6.7   3.7 | -36.8 -34.2  245  34 17   7.0   3.9
 32000 -33.2 -27.8  250  28 15   6.5   3.6 | -32.6 -26.7  245  25 13   6.4   3.5
 30000 -29.5 -21.1  245  21 11   6.3   3.5 | -28.9 -20.0  240  19 10   6.1   3.4
 29000 -27.6 -17.7  240  17  9   6.3   3.5 | -27.1 -16.8  235  16  8   6.2   3.4
 28000 -25.5 -13.9  235  15  8   7.8   4.3 | -25.1 -13.2  230  13  7   7.3   4.0
 27000 -23.2  -9.8  235  14  7   7.7   4.2 | -22.9  -9.2  225  12  6   7.3   4.0
 26000 -20.9  -5.6  230  13  7   7.7   4.2 | -20.7  -5.3  225  12  6   7.3   4.0
 25000 -18.5  -1.3  230  12  6   7.9   4.4 | -18.5  -1.3  220  11  6   8.4   4.6
 24000 -16.2   2.8  230  10  5   8.0   4.4 | -16.0   3.2  215  10  5   8.4   4.6
 23000 -13.8   7.2  225   9  5   8.0   4.4 | -13.5   7.7  210   9  5   8.4   4.6
 22000 -11.4  11.5  220   7  4   7.7   4.2 | -11.0  12.2  200   9  4   7.6   4.2
 21000  -8.6  16.5  195   5  3   7.7   4.2 |  -8.1  17.4  180   8  4   7.7   4.2
 20000  -6.3  20.7  165   4  2   7.6   4.2 |  -5.8  21.6  165   9  5   7.6   4.2
 19500  -5.1  22.8  150   4  2   8.5   4.6 |  -4.7  23.5  160   9  5   8.5   4.7
 19000  -3.8  25.2  145   4  2   8.4   4.6 |  -3.4  25.9  155   9  5   8.5   4.7
 18500  -2.6  27.3  135   5  2   8.4   4.6 |  -2.2  28.0  155  10  5   8.5   4.7
 18000  -1.4  29.5  135   5  3   8.4   4.6 |  -0.9  30.4  150  10  5   8.7   4.7
 17500  -0.1  31.8  130   5  3   8.3   4.6 |   0.4  32.7  150  10  5   8.7   4.8
 17000   1.1  34.0  125   5  3   8.6   4.7 |   1.7  35.1  150   9  5   8.8   4.8
 16500   2.4  36.3  125   5  3   8.6   4.7 |   3.0  37.4  150   9  5   8.8   4.9
 16000   3.7  38.7  125   5  3   8.6   4.7 |   4.3  39.7  145   8  4   9.0   4.9
 15500   5.0  41.0  125   5  3   8.6   4.7 |   5.6  42.1  145   8  4   9.1   5.0
 15000   6.3  43.3  130   5  3   8.7   4.8 |   7.0  44.6  145   7  4   9.1   5.0
 14500   7.6  45.7  130   5  2   8.8   4.8 |   8.3  46.9  145   6  3   9.1   5.0
 14000   8.9  48.0  130   4  2   8.8   4.8 |   9.7  49.5  140   6  3   9.1   5.0
 13500  10.2  50.4  135   4  2   8.7   4.8 |  11.0  51.8  135   5  3   8.9   4.9
 13000  11.4  52.5  140   3  2   8.7   4.8 |  12.3  54.1  125   5  2   8.9   4.9
 12500  12.7  54.9  140   3  1   8.8   4.8 |  13.6  56.5  120   4  2   8.6   4.7
 12000  14.0  57.2  140   2  1   8.8   4.8 |  14.9  58.8  110   4  2   8.6   4.7
 11500  15.3  59.5  135   2  1   8.3   4.6 |  16.2  61.2  100   4  2   8.6   4.7
 11000  16.5  61.7  125   1  0   8.4   4.6 |  17.5  63.5  095   4  2   8.8   4.8
 10500  17.6  63.7  000   0  0   5.5   3.0 |  18.6  65.5  090   4  2   5.1   2.8
 10250  18.0  64.4  000   0  0   7.6   4.2 |  19.0  66.2  085   4  2   8.1   4.4
 10000  18.7  65.7  015   1  0  10.2   5.6 |  19.8  67.6  080   4  2  11.4   6.2
  9750  19.4  66.9  005   1  0   9.2   5.0 |  20.6  69.1  075   4  2  10.3   5.7
  9500  20.0  68.0  355   1  1   6.9   3.8 |  21.3  70.3  070   4  2   7.4   4.0
  9250  20.5  68.9  355   1  1   6.8   3.7 |  21.7  71.1  070   4  2   6.6   3.6
  9000  21.1  70.0  355   1  1   9.5   5.2 |  22.3  72.1  065   4  2   9.3   5.1
  8750  21.8  71.2  350   1  1   9.7   5.3 |  23.0  73.4  065   3  2   9.3   5.1
  8500  22.4  72.3  350   1  1   8.7   4.8 |  23.6  74.5  060   3  2   8.0   4.4
  8250  23.1  73.6  345   1  1   8.0   4.4 |  24.2  75.6  060   3  1   7.4   4.1
  8000  23.7  74.7  340   2  1   9.6   5.3 |  24.7  76.5  055   3  1   7.8   4.3
  7750  24.5  76.1  340   2  1  10.9   6.0 |  25.3  77.5  055   2  1   8.6   4.7
  7500  25.2  77.4  335   2  1  10.0   5.5 |  26.0  78.8  055   2  1   9.8   5.4
  7250  26.0  78.8  330   2  1  10.2   5.6 |  26.7  80.1  055   2  1  10.0   5.5
  7000  26.7  80.1  325   2  1   9.7   5.3 |  27.5  81.5  055   2  1  10.4   5.7
  6750  27.5  81.5  325   2  1  10.2   5.6 |  28.3  82.9  050   1  1  10.7   5.9
  6500  28.3  82.9  320   2  1  11.2   6.2 |  29.1  84.4  055   1  1  10.3   5.7
  6250  29.1  84.4  315   2  1  11.0   6.0 |  29.8  85.6  055   1  1  10.2   5.6
  6000  29.9  85.8  315   2  1  11.2   6.2 |  30.6  87.1  055   1  0  10.4   5.7
  5750  31.0  87.8  310   2  1  18.7  10.2 |  31.5  88.7  060   1  0  14.7   8.1
  5500  32.8  91.0  315   2  1  30.3  16.6 |  32.9  91.2  050   1  0  21.3  11.7
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 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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