Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 161237
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0637 MDT Wednesday, July 16, 2014

This forecast is for Wednesday, July 16, 2014:

If the trigger temperature of 82.5 F/28.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1253 ft/min (6.4 m/s)
   Maximum height of thermals.................. 18633 ft MSL (13794 ft AGL)

Forecast maximum temperature................... 94.0 F/34.9 C
Time of trigger temperature.................... 1045 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................. 12451 ft MSL (7611 ft AGL)
Thermal soaring outlook for Thursday 07/17..... Good

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

Remarks...

Sunrise/Sunset.................... 06:01:23 / 20:39:10 MDT
Total possible sunshine........... 14 hr 37 min 47 sec (877 min 47 sec)
Altitude of sun at 13:20:11 MDT... 72.13 degrees

Upper air data from rawinsonde observation taken on 07/16/2014 at 0600 MDT

Freezing level.................. 15860 ft MSL (11021 ft AGL)
Convective condensation level... 15772 ft MSL (10933 ft AGL)
Lifted condensation level....... 16445 ft MSL (11606 ft AGL)
Lifted index.................... -2.6
K index......................... +26.8

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  -64.0 -83.2   325   39   20   3.4   1.9   88.4 191.1    31.2      M    M
 45000  -63.1 -81.6   305   57   29   4.3   2.3   64.2 147.6    18.6      M    M
 40000  -54.7 -66.5   285   59   30   9.3   5.1   54.5 130.0    13.4      M    M
 38000  -49.0 -56.2   285   58   30   9.4   5.2   54.2 129.5    13.5      M    M
 36000  -44.0 -47.2   285   57   29   5.5   3.0   53.1 127.6    13.1      M    M
 34000  -38.9 -38.0   290   53   27   8.0   4.4   52.1 125.7    12.7      M    M
 32000  -34.4 -29.9   300   48   25   7.8   4.3   49.3 120.7    11.0      M    M
 30000  -29.0 -20.2   295   46   24   7.1   3.9   48.6 119.6    10.8      M    M
 29000  -26.9 -16.4   300   43   22   7.1   3.9   47.6 117.6    10.1      M    M
 28000  -25.0 -13.0   300   41   21   7.5   4.1   46.3 115.4     9.2      M    M
 27000  -22.5  -8.5   305   39   20   8.2   4.5   45.7 114.2     8.8      M    M
 26000  -20.0  -4.0   305   37   19   8.3   4.5   45.1 113.3     8.5      M    M
 25000  -19.2  -2.6   310   35   18   1.8   1.0   42.6 108.6     6.5      M    M
 24000  -17.2   1.0   310   34   17   8.9   4.9   41.3 106.4     5.6      M    M
 23000  -14.6   5.7   305   32   17   8.0   4.4   41.0 105.8     5.4      M    M
 22000  -12.1  10.2   300   31   16   8.0   4.4   40.4 104.7     4.9      M    M
 21000  -10.3  13.5   300   29   15   4.1   2.2   39.1 102.3     3.9      M    M
 20000   -9.2  15.4   295   28   14   4.1   2.3   37.0  98.7     2.2      M    M
 19500   -8.8  16.2   295   30   15   3.0   1.7   35.9  96.7     1.1      M    M
 19000   -8.0  17.6   295   30   16   8.5   4.7   35.3  95.5     0.4      M    M
 18500   -7.0  19.4   295   29   15   6.5   3.6   34.9  94.8    -0.0   1251  6.4
 18000   -5.8  21.6   295   28   14  10.4   5.7   34.7  94.5    -0.3   1202  6.1
 17500   -3.7  25.3   295   26   13   8.8   4.8   34.6  94.3    -0.4   1117  5.7
 17000   -2.6  27.3   300   24   13   8.2   4.5   34.3  93.8    -0.8   1068  5.4
 16500   -1.5  29.3   300   23   12   8.7   4.8   34.1  93.3    -1.1   1020  5.2
 16000   -0.1  31.8   300   22   11   9.1   5.0   34.0  93.2    -1.2    965  4.9
 15500    1.2  34.2   300   20   10   9.1   5.0   33.8  92.9    -1.4    910  4.6
 15000    2.6  36.7   295   19   10   9.1   5.0   33.7  92.7    -1.5    855  4.3
 14500    3.9  39.0   295   17    9   9.0   5.0   33.6  92.5    -1.6    801  4.1
 14000    5.2  41.4   290   16    8   8.0   4.4   33.6  92.4    -1.7    746  3.8
 13500    6.1  43.0   300   18    9   5.8   3.2   33.0  91.4    -2.4    705  3.6
 13000    7.0  44.6   305   20   10   8.3   4.5   32.4  90.4    -2.9    664  3.4
 12500    8.4  47.1   310   23   12   6.9   3.8   32.4  90.4    -3.0    606  3.1
 12000    9.1  48.4   315   25   13   4.6   2.5   31.6  88.8    -3.8    572  2.9
 11500    9.7  49.5   315   21   11   4.3   2.3   30.7  87.3    -4.6    537  2.7
 11000   10.9  51.6   310   18    9  10.7   5.9   30.4  86.7    -4.9    488  2.5
 10500   12.4  54.3   305   15    8  10.0   5.5   30.5  86.8    -4.9    428  2.2
 10250   13.1  55.6   300   14    7   9.2   5.0   30.5  86.8    -4.9    399  2.0
 10000   13.8  56.8   295   14    7   9.0   4.9   30.4  86.7    -5.0    371  1.9
  9750   14.5  58.1   290   14    7   8.6   4.7   30.3  86.6    -5.1    343  1.7
  9500   15.1  59.2   285   14    7  10.3   5.7   30.3  86.5    -5.1    316  1.6
  9250   15.8  60.4   275   14    7   3.5   1.9   30.2  86.4    -5.2    288  1.5
  9000   15.8  60.4   270   15    8   1.7   0.9   29.4  85.0    -5.9    281  1.4
  8750   16.3  61.3   270   14    7   8.5   4.7   29.2  84.5    -6.2    260  1.3
  8500   16.9  62.4   270   12    6   8.2   4.5   29.1  84.3    -6.4    234  1.2
  8250   17.5  63.5   275   11    6   8.2   4.5   28.9  84.1    -6.5    209  1.1
  8000   18.1  64.6   275    9    5   8.8   4.8   28.8  83.9    -6.6    184  0.9
  7750   18.6  65.5   280    8    4   4.7   2.6   28.7  83.6    -6.8    160  0.8
  7500   18.7  65.7   285    6    3   0.9   0.5   28.1  82.5    -7.5    150  0.8
  7250   18.7  65.7   295    4    2   2.2   1.2   27.4  81.4    -8.2    141  0.7
  7000   18.9  66.0   315    3    2   5.2   2.8   27.0  80.5    -8.7    127  0.6
  6750   19.5  67.1   320    2    1   7.3   4.0   26.7  80.1    -9.0    104  0.5
  6500   20.0  68.0   325    1    0   6.8   3.7   26.5  79.7    -9.2     81  0.4
  6250   20.5  68.9   000    0    0   6.8   3.7   26.3  79.3    -9.4     58  0.3
  6000   21.1  70.0   135    2    1   7.5   4.1   26.1  78.9    -9.6     34  0.2
  5750   21.6  70.9   130    2    1   4.7   2.6   25.9  78.6    -9.8     11  0.1
  5500   21.8  71.2   120    3    1   1.8   1.0   25.3  77.6   -10.4      M    M
  5250   22.0  71.6   115    3    2   3.0   1.7   24.8  76.6   -10.9      M    M
  5000   22.1  71.8   110    4    2  -3.0  -1.6   24.1  75.4   -11.6      M    M

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

           07/16/2014 at 0900 MDT          |       07/16/2014 at 1200 MDT
                                           |
K index... +33.9  LI... -2.8               | K index... +32.9  LI... -2.9
CAPE... +451.6  CIN... -86.5               | CAPE... +725.7  CIN... -30.9
                                           |
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 -65.3 -85.5  315  31 16   0.9   0.5 | -65.0 -85.0  310  31 16   1.5   0.8
 45000 -61.9 -79.4  305  55 28   5.2   2.8 | -61.1 -78.0  305  49 25   5.1   2.8
 40000 -53.7 -64.7  305  69 35   7.7   4.2 | -53.1 -63.6  305  58 30   6.9   3.8
 38000 -49.0 -56.2  305  65 33   7.7   4.2 | -48.9 -56.0  310  56 29   7.0   3.8
 36000 -44.4 -47.9  305  61 31   7.7   4.2 | -44.7 -48.5  310  55 28   6.9   3.8
 34000 -39.5 -39.1  305  55 29   8.3   4.5 | -40.0 -40.0  310  51 26   8.1   4.4
 32000 -33.9 -29.0  310  49 25   8.5   4.7 | -34.5 -30.1  305  46 24   8.5   4.7
 30000 -29.5 -21.1  310  46 24   7.1   3.9 | -30.1 -22.2  305  43 22   7.2   3.9
 29000 -27.4 -17.3  310  44 23   7.1   3.9 | -28.0 -18.4  305  42 22   7.2   3.9
 28000 -25.3 -13.5  310  43 22   6.8   3.7 | -25.8 -14.4  305  41 21   7.3   4.0
 27000 -23.3  -9.9  310  42 22   6.7   3.7 | -23.6 -10.5  310  41 21   7.3   4.0
 26000 -21.3  -6.3  310  41 21   6.7   3.7 | -21.4  -6.5  310  41 21   7.3   4.0
 25000 -19.3  -2.7  310  40 20   6.7   3.7 | -19.3  -2.7  310  42 21   7.3   4.0
 24000 -17.3   0.9  310  38 20   6.6   3.6 | -17.1   1.2  310  41 21   7.3   4.0
 23000 -15.3   4.5  310  37 19   6.6   3.6 | -14.9   5.2  305  39 20   7.3   4.0
 22000 -13.4   7.9  310  35 18   6.7   3.6 | -12.7   9.1  305  38 19   7.1   3.9
 21000 -11.4  11.5  310  34 18   6.8   3.8 | -10.7  12.7  305  37 19   6.8   3.7
 20000  -9.4  15.1  310  33 17   7.0   3.8 |  -8.7  16.3  305  35 18   6.8   3.7
 19500  -8.4  16.9  310  33 17   7.3   4.0 |  -7.7  18.1  305  35 18   7.0   3.8
 19000  -7.5  18.5  310  32 16   4.8   2.6 |  -6.8  19.8  305  34 18   5.7   3.1
 18500  -6.9  19.6  305  31 16   5.2   2.8 |  -6.0  21.2  305  34 18   5.9   3.2
 18000  -6.2  20.8  300  30 16   6.7   3.7 |  -5.2  22.6  300  34 17   6.3   3.4
 17500  -5.0  23.0  300  29 15   8.8   4.8 |  -4.3  24.3  300  33 17   6.8   3.8
 17000  -3.8  25.2  295  28 14   9.0   5.0 |  -3.4  25.9  295  32 17   6.9   3.8
 16500  -2.6  27.3  295  27 14   8.5   4.7 |  -2.3  27.9  295  31 16   8.0   4.4
 16000  -1.4  29.5  295  26 13   8.6   4.7 |  -1.2  29.8  290  30 16   8.0   4.4
 15500  -0.2  31.6  295  25 13   8.4   4.6 |   0.5  32.9  290  29 15   8.4   4.6
 15000   1.6  34.9  295  23 12   8.4   4.6 |   1.7  35.1  285  27 14   8.3   4.6
 14500   2.8  37.0  295  22 11   8.0   4.4 |   3.0  37.4  285  26 14   8.8   4.8
 14000   4.0  39.2  295  21 11   8.0   4.4 |   4.3  39.7  285  25 13   8.8   4.8
 13500   5.2  41.4  290  21 11   8.7   4.7 |   5.5  41.9  285  24 12   9.1   5.0
 13000   6.5  43.7  290  20 10   8.9   4.9 |   6.9  44.4  280  23 12   9.2   5.1
 12500   7.9  46.2  290  19 10   9.2   5.0 |   8.3  46.9  280  22 12   9.2   5.1
 12000   9.3  48.7  290  18  9   9.4   5.2 |   9.6  49.3  280  22 11   9.3   5.1
 11500  10.7  51.3  290  18  9   9.5   5.2 |  11.0  51.8  280  21 11   9.3   5.1
 11000  12.1  53.8  290  17  9   9.3   5.1 |  12.4  54.3  275  20 10   9.1   5.0
 10500  13.5  56.3  290  17  9   5.7   3.1 |  13.8  56.8  275  18  9   6.7   3.7
 10250  13.8  56.8  290  17  9   6.6   3.6 |  14.1  57.4  275  18  9   7.4   4.0
 10000  14.6  58.3  290  17  9  12.2   6.7 |  14.9  58.8  275  17  9  11.0   6.0
  9750  15.4  59.7  290  16  8  11.2   6.2 |  15.6  60.1  270  17  9  10.6   5.8
  9500  16.3  61.3  290  16  8   9.5   5.2 |  16.4  61.5  270  16  8   8.4   4.6
  9250  16.8  62.2  285  16  8   8.0   4.4 |  16.9  62.4  270  16  8   6.6   3.6
  9000  17.5  63.5  285  15  8   9.3   5.1 |  17.5  63.5  265  15  8   8.2   4.5
  8750  18.2  64.8  280  14  7   9.9   5.4 |  18.1  64.6  265  14  7   8.2   4.5
  8500  18.9  66.0  280  14  7   7.7   4.2 |  18.7  65.7  265  13  7   7.6   4.2
  8250  19.3  66.7  275  13  7   5.4   3.0 |  19.2  66.6  260  12  6   6.9   3.8
  8000  19.7  67.5  275  11  6   5.4   3.0 |  19.7  67.5  260  11  6   7.7   4.2
  7750  20.1  68.2  270  10  5   4.9   2.7 |  20.2  68.4  260  10  5   8.1   4.4
  7500  20.4  68.7  265   8  4   4.6   2.5 |  20.8  69.4  260   8  4   8.8   4.8
  7250  20.7  69.3  250   7  4   4.2   2.3 |  21.5  70.7  260   8  4   9.6   5.3
  7000  21.0  69.8  235   6  3   4.7   2.6 |  22.2  72.0  260   8  4   9.1   5.0
  6750  21.4  70.5  220   6  3   5.5   3.0 |  22.8  73.0  260   8  4   9.4   5.1
  6500  21.8  71.2  205   6  3   6.0   3.3 |  23.6  74.5  260   7  4  10.5   5.8
  6250  22.2  72.0  195   6  3   6.4   3.5 |  24.4  75.9  260   7  4  11.4   6.3
  6000  22.6  72.7  185   5  3   5.7   3.1 |  25.2  77.4  265   7  4   9.8   5.4
  5750  23.0  73.4  180   5  3   7.5   4.1 |  25.9  78.6  265   7  4  10.9   6.0
  5500  23.7  74.7  180   5  3  10.2   5.6 |  26.9  80.4  265   7  4  14.2   7.8
  5250  24.4  75.9  180   5  2   8.3   4.5 |  27.9  82.2  265   7  4  12.8   7.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/16/2014 at 1500 MDT          |       07/16/2014 at 1800 MDT
                                           |
K index... +32.5  LI... -2.8               | K index... +30.4  LI... -2.1
CAPE... +687.3  CIN... -11.2               | CAPE... +364.5  CIN... -13.2
                                           |
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 -64.2 -83.6  310  34 17   1.3   0.7 | -63.9 -83.0  320  31 16   1.6   0.9
 45000 -60.6 -77.1  305  52 27   4.9   2.7 | -60.1 -76.2  310  49 25   4.6   2.5
 40000 -52.9 -63.2  305  60 31   7.0   3.8 | -52.8 -63.0  310  55 29   6.9   3.8
 38000 -48.6 -55.5  300  59 30   7.1   3.9 | -48.6 -55.5  310  53 27   7.0   3.8
 36000 -44.4 -47.9  300  57 30   7.0   3.9 | -44.4 -47.9  305  50 26   7.0   3.8
 34000 -39.8 -39.6  300  52 27   7.6   4.2 | -40.0 -40.0  305  46 24   7.4   4.0
 32000 -34.7 -30.5  295  45 23   7.9   4.3 | -35.0 -31.0  300  42 21   7.4   4.0
 30000 -30.2 -22.4  300  41 21   7.4   4.1 | -30.3 -22.5  300  40 21   7.9   4.3
 29000 -28.0 -18.4  300  39 20   7.4   4.1 | -27.9 -18.2  300  39 20   7.9   4.3
 28000 -25.7 -14.3  300  37 19   7.3   4.0 | -25.5 -13.9  300  39 20   7.5   4.1
 27000 -23.6 -10.5  300  38 20   7.3   4.0 | -23.3  -9.9  300  39 20   7.4   4.0
 26000 -21.4  -6.5  305  39 20   7.3   4.0 | -21.1  -6.0  300  40 20   7.4   4.0
 25000 -19.2  -2.6  305  40 21   7.3   4.0 | -18.9  -2.0  300  40 21   7.3   4.0
 24000 -17.0   1.4  305  41 21   7.4   4.0 | -16.8   1.8  300  41 21   6.8   3.7
 23000 -14.8   5.4  305  41 21   7.4   4.0 | -14.8   5.4  300  41 21   6.8   3.7
 22000 -12.6   9.3  305  41 21   7.2   3.9 | -12.8   9.0  305  41 21   6.7   3.7
 21000 -10.6  12.9  310  40 21   6.8   3.7 | -10.8  12.6  305  39 20   6.5   3.5
 20000  -8.6  16.5  310  38 20   6.8   3.7 |  -8.9  16.0  310  36 19   6.5   3.6
 19500  -7.6  18.3  310  37 19   6.8   3.7 |  -8.0  17.6  310  35 18   6.5   3.6
 19000  -6.6  20.1  310  36 19   7.1   3.9 |  -7.0  19.4  310  33 17   7.5   4.1
 18500  -5.6  21.9  310  35 18   7.2   3.9 |  -5.9  21.4  310  32 16   7.7   4.2
 18000  -4.6  23.7  305  34 18   6.9   3.8 |  -4.8  23.4  310  30 15   7.8   4.3
 17500  -3.7  25.3  305  33 17   6.2   3.4 |  -3.8  25.2  305  28 14   7.8   4.3
 17000  -2.9  26.8  300  31 16   6.2   3.4 |  -2.7  27.1  305  26 13   7.9   4.3
 16500  -1.9  28.6  295  29 15   8.6   4.7 |  -1.6  29.1  305  24 13   8.6   4.7
 16000  -0.7  30.7  295  26 14   8.6   4.7 |  -0.4  31.3  305  23 12   8.6   4.7
 15500   1.1  34.0  290  24 12   8.9   4.9 |   0.9  33.6  300  21 11   8.9   4.9
 15000   2.4  36.3  285  23 12   8.9   4.9 |   2.8  37.0  300  20 11   9.1   5.0
 14500   3.7  38.7  285  22 11   8.8   4.8 |   4.2  39.6  295  20 10   9.3   5.1
 14000   5.0  41.0  285  21 11   8.8   4.8 |   5.6  42.1  295  19 10   9.3   5.1
 13500   6.2  43.2  280  21 11   8.9   4.9 |   7.0  44.6  295  19 10   9.4   5.2
 13000   7.5  45.5  280  21 11   8.9   4.9 |   8.4  47.1  290  19 10   9.5   5.2
 12500   8.9  48.0  280  21 11   9.1   5.0 |   9.8  49.6  290  18 10   9.6   5.2
 12000  10.2  50.4  280  20 10   9.3   5.1 |  11.2  52.2  285  18  9   9.6   5.3
 11500  11.6  52.9  275  20 10   9.1   5.0 |  12.6  54.7  285  18 10   9.2   5.1
 11000  12.9  55.2  275  19 10   8.6   4.7 |  13.8  56.8  280  18  9   7.6   4.2
 10500  14.1  57.4  275  19 10  11.5   6.3 |  14.9  58.8  275  18  9  10.5   5.8
 10250  15.1  59.2  270  18  9  11.8   6.5 |  15.8  60.4  275  17  9  11.4   6.2
 10000  15.8  60.4  270  17  9   7.8   4.3 |  16.5  61.7  275  17  9   8.2   4.5
  9750  16.4  61.5  270  17  9   9.2   5.0 |  17.1  62.8  275  16  8   8.9   4.9
  9500  17.0  62.6  270  16  8   7.7   4.2 |  17.8  64.0  275  16  8   9.1   5.0
  9250  17.6  63.7  270  15  8   8.3   4.5 |  18.5  65.3  275  15  8   9.6   5.3
  9000  18.3  64.9  270  15  8   9.8   5.4 |  19.2  66.6  270  15  8   9.6   5.3
  8750  19.0  66.2  270  14  7   9.3   5.1 |  19.9  67.8  270  15  8   9.5   5.2
  8500  19.7  67.5  265  14  7   9.9   5.5 |  20.6  69.1  270  15  8  10.0   5.5
  8250  20.4  68.7  265  14  7  10.5   5.8 |  21.4  70.5  270  15  8  10.8   5.9
  8000  21.2  70.2  265  14  7  10.0   5.5 |  22.2  72.0  270  15  7  10.0   5.5
  7750  21.9  71.4  265  14  7   9.6   5.2 |  22.9  73.2  270  14  7   9.2   5.1
  7500  22.7  72.9  265  13  7  10.1   5.5 |  23.6  74.5  270  14  7   9.9   5.4
  7250  23.4  74.1  265  13  7  10.4   5.7 |  24.4  75.9  270  14  7  10.9   6.0
  7000  24.2  75.6  265  13  7  10.4   5.7 |  25.2  77.4  270  14  7  10.1   5.6
  6750  25.0  77.0  265  13  7  10.6   5.8 |  25.9  78.6  270  14  7   9.0   4.9
  6500  25.8  78.4  265  13  7  10.7   5.9 |  26.6  79.9  270  14  7  10.1   5.5
  6250  26.6  79.9  265  13  6  11.0   6.0 |  27.4  81.3  270  13  7  11.1   6.1
  6000  27.4  81.3  265  12  6  10.4   5.7 |  28.2  82.8  270  13  7  10.5   5.7
  5750  28.2  82.8  265  12  6  12.0   6.6 |  29.0  84.2  270  12  6  10.4   5.7
  5500  29.2  84.6  265  12  6  15.3   8.4 |  29.8  85.6  270  12  6  11.7   6.4
  5250  30.4  86.7  265  12  6  15.6   8.5 |  30.7  87.3  270  12  6  12.9   7.1
  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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