Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 301230
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0629 MDT Saturday, August 30, 2014

This forecast is for Saturday, August 30, 2014:

If the trigger temperature of 80.3 F/26.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 735 ft/min (3.7 m/s)
   Maximum height of thermals.................. 17155 ft MSL (12316 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1100 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................. 10304 ft MSL (5464 ft AGL)
Thermal soaring outlook for Sunday 08/31....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:41:02 / 19:49:02 MDT
Total possible sunshine........... 13 hr 8 min 0 sec (788 min 0 sec)
Altitude of sun at 13:14:37 MDT... 59.70 degrees

Upper air data from rawinsonde observation taken on 08/30/2014 at 0600 MDT

Freezing level.................. 14884 ft MSL (10045 ft AGL)
Convective condensation level... 14516 ft MSL (9677 ft AGL)
Lifted condensation level....... 15104 ft MSL (10265 ft AGL)
Lifted index.................... -2.7
K index......................... +24.0

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  -65.4 -85.7   290   35   18  -3.4  -1.8   86.5 187.8    32.0      M    M
 45000  -61.0 -77.8   295   45   23   1.7   0.9   69.4 156.9    23.7      M    M
 40000  -54.0 -65.2   300   48   25   5.2   2.9   56.5 133.7    16.9      M    M
 38000  -51.8 -61.2   300   50   25   3.6   2.0   51.1 123.9    13.6      M    M
 36000  -47.0 -52.6   300   51   26   9.4   5.1   49.6 121.2    12.9      M    M
 34000  -41.5 -42.7   295   51   26   9.0   5.0   49.2 120.6    13.0      M    M
 32000  -36.5 -33.7   300   45   23   9.8   5.4   48.1 118.6    12.5      M    M
 30000  -31.9 -25.4   300   38   19   7.9   4.3   45.5 114.0    10.9      M    M
 29000  -29.4 -20.9   300   35   18   7.4   4.1   45.0 113.0    10.5      M    M
 28000  -26.9 -16.4   295   32   17   8.8   4.8   44.5 112.1    10.3      M    M
 27000  -24.7 -12.5   295   29   15   6.1   3.4   43.5 110.2     9.6      M    M
 26000  -23.0  -9.4   290   27   14   5.2   2.9   41.9 107.5     8.5      M    M
 25000  -21.2  -6.2   290   29   15   4.6   2.5   40.6 105.1     7.5      M    M
 24000  -19.0  -2.2   290   28   14   9.2   5.1   39.6 103.3     6.8      M    M
 23000  -16.7   1.9   295   26   13   6.6   3.6   39.0 102.1     6.4      M    M
 22000  -14.4   6.1   300   24   13   5.6   3.1   38.2 100.7     5.8      M    M
 21000  -13.6   7.5   305   23   12   3.4   1.9   35.9  96.7     3.8      M    M
 20000  -12.4   9.7   310   22   11   7.2   4.0   33.9  93.1     2.0      M    M
 19500  -11.4  11.5   310   22   11   6.8   3.8   33.5  92.2     1.6      M    M
 19000  -10.4  13.3   310   22   11   7.5   4.1   33.0  91.4     1.2      M    M
 18500   -9.2  15.4   310   21   11   9.0   4.9   32.7  90.9     0.9      M    M
 18000   -7.9  17.8   310   20   10   9.2   5.0   32.6  90.6     0.8      M    M
 17500   -6.7  19.9   310   19   10   6.9   3.8   32.3  90.2     0.5      M    M
 17000   -5.8  21.6   310   18    9   7.5   4.1   31.8  89.2    -0.0   1132  5.7
 16500   -3.8  25.2   310   17    9   9.1   5.0   31.6  88.8    -0.2   1049  5.3
 16000   -2.5  27.5   310   16    8   8.1   4.5   31.4  88.5    -0.4    996  5.1
 15500   -1.3  29.7   305   15    8   8.2   4.5   31.1  88.0    -0.6    945  4.8
 15000   -0.0  32.0   305   14    7   8.3   4.6   30.8  87.5    -0.9    894  4.5
 14500    1.1  34.0   300   13    7   6.9   3.8   30.5  87.0    -1.2    845  4.3
 14000    2.0  35.6   295   12    6   7.3   4.0   30.0  86.1    -1.7    803  4.1
 13500    3.3  37.9   290   11    6   9.0   4.9   29.8  85.6    -2.0    750  3.8
 13000    4.6  40.3   285   10    5   8.9   4.9   29.7  85.4    -2.1    695  3.5
 12500    6.0  42.8   280    9    4   8.9   4.9   29.5  85.2    -2.2    640  3.2
 12000    7.3  45.1   270    8    4   8.9   4.9   29.4  85.0    -2.3    584  3.0
 11500    8.7  47.7   255    8    4   9.0   4.9   29.3  84.7    -2.4    529  2.7
 11000    9.9  49.8   240    9    4   8.4   4.6   29.1  84.4    -2.6    476  2.4
 10500   11.1  52.0   225   10    5   8.4   4.6   28.9  84.1    -2.9    426  2.2
 10250   11.7  53.1   220   10    5   8.0   4.4   28.8  83.8    -3.0    402  2.0
 10000   12.2  54.0   210    9    5   7.9   4.3   28.6  83.6    -3.2    378  1.9
  9750   12.8  55.0   200    9    4   7.9   4.3   28.5  83.3    -3.4    354  1.8
  9500   13.3  55.9   185    9    5   7.9   4.3   28.4  83.0    -3.6    330  1.7
  9250   13.9  57.0   175    9    5   8.0   4.4   28.2  82.8    -3.8    306  1.6
  9000   14.5  58.1   165   10    5   7.9   4.3   28.1  82.6    -4.0    282  1.4
  8750   15.0  59.0   165   11    6   8.4   4.6   27.9  82.3    -4.1    258  1.3
  8500   15.6  60.1   160   13    7   6.4   3.5   27.8  82.1    -4.3    234  1.2
  8250   15.9  60.6   160   14    7   4.1   2.2   27.4  81.4    -4.7    216  1.1
  8000   16.2  61.2   160   16    8   4.6   2.6   27.0  80.6    -5.1    199  1.0
  7750   16.6  61.9   160   16    8   3.8   2.1   26.6  79.9    -5.5    181  0.9
  7500   16.7  62.1   155   15    8  -0.8  -0.4   26.0  78.8    -6.1    170  0.9
  7250   16.4  61.5   155   15    8  -4.0  -2.2   25.0  77.0    -7.1    171  0.9
  7000   16.2  61.2   150   15    8   1.8   1.0   24.1  75.4    -8.1    169  0.9
  6750   16.6  61.9   145   13    7   5.7   3.1   23.7  74.7    -8.5    152  0.8
  6500   16.9  62.4   135   10    5   4.6   2.6   23.4  74.1    -8.9    134  0.7
  6250   17.2  63.0   120    8    4   5.0   2.7   23.0  73.4    -9.3    117  0.6
  6000   17.6  63.7   100    7    4   4.8   2.7   22.6  72.8    -9.7    100  0.5
  5750   17.9  64.2   095    7    4   5.0   2.8   22.3  72.1   -10.2     82  0.4
  5500   18.2  64.8   100    7    4   4.4   2.4   21.9  71.4   -10.6     65  0.3
  5250   18.6  65.5   100    7    4   6.8   3.7   21.5  70.8   -11.0     48  0.2
  5000   18.9  66.0   105    7    4  -1.9  -1.1   21.2  70.1   -11.4     30  0.2

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

           08/30/2014 at 0900 MDT          |       08/30/2014 at 1200 MDT
                                           |
K index... +26.9  LI... -1.9               | K index... +26.7  LI... -2.7
CAPE... +132.2  CIN... -36.9               | CAPE... +185.9  CIN... -54.0
                                           |
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 -64.4 -83.9  300  30 15   1.1   0.6 | -64.9 -84.8  285  38 20   1.2   0.7
 45000 -60.9 -77.6  300  39 20   5.9   3.2 | -61.2 -78.2  290  49 25   6.1   3.3
 40000 -51.9 -61.4  305  45 23   4.8   2.6 | -51.7 -61.1  285  44 23   5.3   2.9
 38000 -49.0 -56.2  300  53 27   4.7   2.6 | -48.5 -55.3  285  50 26   5.3   2.9
 36000 -46.2 -51.2  295  61 31   4.7   2.6 | -45.4 -49.7  285  57 29   5.1   2.8
 34000 -41.7 -43.1  295  56 29   8.2   4.5 | -41.0 -41.8  285  52 27   7.7   4.2
 32000 -36.8 -34.2  300  47 24   8.2   4.5 | -36.4 -33.5  285  44 23   7.8   4.3
 30000 -32.1 -25.8  300  39 20   7.7   4.2 | -31.7 -25.1  280  38 20   8.0   4.4
 29000 -29.8 -21.6  295  34 18   7.7   4.2 | -29.3 -20.7  280  35 18   8.0   4.4
 28000 -27.0 -16.6  295  29 15   6.9   3.8 | -26.4 -15.5  275  32 16   6.9   3.8
 27000 -25.1 -13.2  290  29 15   6.4   3.5 | -24.5 -12.1  275  32 16   6.5   3.5
 26000 -23.2  -9.8  290  29 15   6.4   3.5 | -22.6  -8.7  280  31 16   6.5   3.5
 25000 -21.3  -6.3  285  29 15   6.4   3.5 | -20.7  -5.3  280  31 16   6.4   3.5
 24000 -19.7  -3.5  285  28 14   5.3   2.9 | -19.1  -2.4  280  29 15   5.1   2.8
 23000 -18.1  -0.6  285  26 13   5.3   2.9 | -17.6   0.3  275  26 14   5.1   2.8
 22000 -16.6   2.1  285  24 13   5.7   3.2 | -16.1   3.0  275  24 12   5.5   3.0
 21000 -14.4   6.1  285  22 11   7.5   4.1 | -14.1   6.6  270  23 12   7.1   3.9
 20000 -12.2  10.0  280  20 10   7.5   4.1 | -12.0  10.4  270  22 11   7.1   3.9
 19500 -11.1  12.0  280  19 10   7.5   4.1 | -11.0  12.2  265  21 11   7.0   3.9
 19000 -10.0  14.0  280  18  9   8.3   4.5 |  -9.9  14.2  265  21 11   8.1   4.4
 18500  -8.8  16.2  280  18  9   8.3   4.5 |  -8.7  16.3  265  20 10   8.1   4.4
 18000  -7.6  18.3  280  17  9   8.4   4.6 |  -7.5  18.5  265  19 10   8.4   4.6
 17500  -6.3  20.7  280  17  9   8.5   4.7 |  -6.2  20.8  260  18  9   9.0   5.0
 17000  -5.1  22.8  280  17  9   8.5   4.7 |  -4.9  23.2  260  17  9   9.1   5.0
 16500  -3.8  25.2  280  17  9   8.9   4.9 |  -3.6  25.5  260  17  9   8.6   4.7
 16000  -2.5  27.5  280  18  9   8.9   4.9 |  -2.3  27.9  260  17  9   8.6   4.7
 15500  -1.2  29.8  275  18  9   9.0   4.9 |  -1.1  30.0  255  17  9   8.3   4.5
 15000   0.1  32.2  270  17  9   9.0   4.9 |   0.1  32.2  250  18 10   8.1   4.4
 14500   1.5  34.7  265  17  9   8.9   4.9 |   1.3  34.3  250  20 10   8.2   4.5
 14000   2.7  36.9  260  17  9   8.6   4.7 |   2.5  36.5  245  21 11   8.5   4.7
 13500   4.6  40.3  255  17  8   8.5   4.7 |   4.4  39.9  245  22 11   9.6   5.3
 13000   5.8  42.4  250  16  8   8.5   4.7 |   5.9  42.6  240  22 11  10.1   5.5
 12500   7.1  44.8  245  15  8   8.8   4.8 |   7.4  45.3  240  22 11   9.6   5.3
 12000   8.4  47.1  240  14  7   9.0   4.9 |   8.8  47.8  240  21 11   9.1   5.0
 11500   9.7  49.5  230  13  7   8.8   4.8 |  10.1  50.2  235  20 11   8.9   4.9
 11000  11.0  51.8  230  13  7   8.2   4.5 |  11.4  52.5  235  19 10   8.5   4.6
 10500  12.2  54.0  225  12  6   5.0   2.8 |  12.7  54.9  230  18  9   5.8   3.2
 10250  12.5  54.5  220  12  6   6.1   3.3 |  13.0  55.4  230  18  9   6.6   3.6
 10000  13.2  55.8  220  12  6  11.0   6.0 |  13.7  56.7  230  17  9  10.7   5.8
  9750  14.0  57.2  215  13  6  10.2   5.6 |  14.4  57.9  230  17  9  10.1   5.5
  9500  14.7  58.5  215  13  7   8.5   4.7 |  15.1  59.2  225  16  8   8.5   4.7
  9250  15.2  59.4  210  13  7   6.5   3.6 |  15.6  60.1  225  16  8   7.1   3.9
  9000  15.8  60.4  205  13  7   7.4   4.0 |  16.2  61.2  225  15  8   8.2   4.5
  8750  16.3  61.3  200  14  7   7.8   4.3 |  16.8  62.2  220  14  7   8.4   4.6
  8500  16.9  62.4  200  15  8   6.6   3.6 |  17.4  63.3  215  14  7   7.5   4.1
  8250  17.3  63.1  195  15  8   5.4   3.0 |  17.9  64.2  210  13  6   6.6   3.6
  8000  17.7  63.9  190  15  8   4.8   2.7 |  18.4  65.1  205  12  6   7.0   3.8
  7750  18.0  64.4  185  15  8   4.0   2.2 |  18.9  66.0  200  11  6   7.1   3.9
  7500  18.3  64.9  180  16  8   3.2   1.7 |  19.4  66.9  200  10  5   8.6   4.7
  7250  18.5  65.3  175  16  8   2.4   1.3 |  20.1  68.2  200  10  5   9.8   5.4
  7000  18.7  65.7  170  16  8   2.6   1.4 |  20.9  69.6  200  10  5   9.3   5.1
  6750  18.8  65.8  165  16  8   1.1   0.6 |  21.5  70.7  200  10  5   9.7   5.3
  6500  18.8  65.8  165  14  7  -1.4  -0.8 |  22.3  72.1  200   9  5  10.8   5.9
  6250  18.6  65.5  160  12  6  -0.9  -0.5 |  23.1  73.6  200   9  5  11.3   6.2
  6000  18.4  65.1  155  10  5  -4.4  -2.4 |  24.0  75.2  200   9  5  10.4   5.7
  5750  18.0  64.4  145   7  4   0.9   0.5 |  24.7  76.5  200   9  4  11.5   6.3
  5500  18.6  65.5  140   7  3  10.2   5.6 |  25.6  78.1  200   8  4  13.7   7.5
  5250  19.1  66.4  140   6  3   2.9   1.6 |  26.6  79.9  200   8  4  12.2   6.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/30/2014 at 1500 MDT          |       08/30/2014 at 1800 MDT
                                           |
K index... +27.6  LI... -2.1               | K index... +24.6  LI... -0.9
CAPE... +191.8  CIN... -16.3               | CAPE... +84.1  CIN... -56.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.0 -85.0  275  39 20   1.5   0.8 | -64.0 -83.2  280  45 23   1.6   0.9
 45000 -60.9 -77.6  285  56 29   6.1   3.4 | -60.3 -76.5  280  59 30   4.8   2.6
 40000 -51.5 -60.7  275  58 30   5.1   2.8 | -52.6 -62.7  275  62 32   5.7   3.1
 38000 -48.4 -55.1  275  59 30   5.0   2.8 | -49.2 -56.6  275  60 31   5.7   3.1
 36000 -45.4 -49.7  275  60 31   4.9   2.7 | -45.7 -50.3  275  58 30   5.7   3.1
 34000 -41.1 -42.0  275  53 27   7.8   4.3 | -41.6 -42.9  270  51 26   7.2   4.0
 32000 -36.4 -33.5  275  45 23   7.8   4.3 | -37.3 -35.1  265  42 22   7.3   4.0
 30000 -31.8 -25.2  275  41 21   7.7   4.2 | -32.5 -26.5  265  39 20   8.3   4.6
 29000 -29.5 -21.1  275  39 20   7.8   4.3 | -30.0 -22.0  270  38 19   8.4   4.6
 28000 -27.2 -17.0  275  38 20   7.7   4.2 | -27.5 -17.5  275  37 19   8.3   4.6
 27000 -24.7 -12.5  270  36 19   6.8   3.7 | -25.5 -13.9  275  39 20   6.7   3.7
 26000 -22.7  -8.9  270  35 18   6.8   3.7 | -23.0  -9.4  275  43 22   6.8   3.7
 25000 -20.7  -5.3  270  34 18   6.8   3.7 | -21.0  -5.8  275  46 24   6.8   3.7
 24000 -18.7  -1.7  270  33 17   6.8   3.7 | -19.1  -2.4  275  46 23   6.3   3.5
 23000 -16.7   1.9  270  33 17   6.8   3.8 | -17.2   1.0  270  45 23   6.3   3.5
 22000 -14.6   5.7  265  32 17   6.8   3.7 | -15.4   4.3  265  44 23   6.6   3.6
 21000 -12.7   9.1  260  32 16   6.6   3.6 | -13.1   8.4  260  42 22   7.8   4.3
 20000 -10.8  12.6  255  32 17   6.6   3.6 | -10.8  12.6  255  39 20   7.8   4.3
 19500  -9.8  14.4  250  33 17   6.5   3.5 |  -9.6  14.7  255  38 20   7.9   4.3
 19000  -8.8  16.2  250  33 17   7.9   4.3 |  -8.5  16.7  250  37 19   7.5   4.1
 18500  -7.6  18.3  245  32 17   7.9   4.3 |  -7.4  18.7  250  36 18   7.6   4.2
 18000  -6.5  20.3  245  31 16   7.7   4.2 |  -6.3  20.7  245  35 18   7.9   4.3
 17500  -5.4  22.3  245  31 16   7.0   3.9 |  -5.1  22.8  245  34 17   8.7   4.8
 17000  -4.4  24.1  245  30 16   7.0   3.8 |  -3.8  25.2  240  32 17   8.7   4.8
 16500  -3.3  26.1  240  30 15   7.9   4.3 |  -2.5  27.5  240  31 16   9.3   5.1
 16000  -2.2  28.0  240  29 15   7.9   4.3 |  -1.2  29.8  240  31 16   9.4   5.1
 15500  -1.0  30.2  240  29 15   8.5   4.7 |   0.2  32.4  240  30 15   9.3   5.1
 15000   0.3  32.5  240  28 14   8.9   4.9 |   1.6  34.9  240  29 15   9.2   5.1
 14500   1.6  34.9  240  27 14   9.3   5.1 |   2.9  37.2  240  28 15   9.3   5.1
 14000   3.1  37.6  240  26 13  10.5   5.8 |   4.3  39.7  240  28 14   9.5   5.2
 13500   4.6  40.3  240  25 13  10.5   5.8 |   5.7  42.3  240  27 14   9.5   5.2
 13000   6.8  44.2  240  24 12   9.8   5.4 |   7.8  46.0  245  26 13   9.1   5.0
 12500   8.3  46.9  240  24 12   9.5   5.2 |   9.1  48.4  245  25 13   9.1   5.0
 12000   9.6  49.3  240  23 12   9.0   4.9 |  10.5  50.9  245  24 12   9.1   5.0
 11500  11.0  51.8  240  22 11   8.5   4.7 |  11.8  53.2  250  23 12   8.9   4.9
 11000  12.1  53.8  240  20 10   7.4   4.1 |  13.0  55.4  250  22 11   7.9   4.3
 10500  13.2  55.8  240  19 10  10.5   5.8 |  14.2  57.6  250  20 10  10.3   5.7
 10250  14.1  57.4  240  18  9  11.3   6.2 |  15.1  59.2  250  19 10  10.8   5.9
 10000  14.7  58.5  240  17  9   7.4   4.1 |  15.7  60.3  255  19 10   7.8   4.3
  9750  15.3  59.5  245  15  8   8.8   4.9 |  16.3  61.3  255  18  9   8.7   4.8
  9500  15.9  60.6  245  14  7   7.0   3.8 |  17.0  62.6  255  17  9   8.3   4.6
  9250  16.4  61.5  245  13  6   7.4   4.1 |  17.5  63.5  255  16  8   8.2   4.5
  9000  17.0  62.6  250  12  6   9.5   5.2 |  18.1  64.6  255  15  8   8.2   4.5
  8750  17.7  63.9  250  11  5   9.0   4.9 |  18.7  65.7  260  13  7   8.1   4.4
  8500  18.3  64.9  255  10  5   9.6   5.3 |  19.4  66.9  260  12  6   8.5   4.7
  8250  19.1  66.4  255   9  5  10.1   5.5 |  20.0  68.0  265  11  6   9.2   5.0
  8000  19.8  67.6  255   9  5   9.8   5.4 |  20.7  69.3  265  10  5   8.8   4.8
  7750  20.5  68.9  255   9  5   9.4   5.2 |  21.3  70.3  270  10  5   8.2   4.5
  7500  21.2  70.2  255   9  5   9.8   5.4 |  21.9  71.4  275  10  5   8.8   4.8
  7250  22.0  71.6  255   9  5  10.2   5.6 |  22.6  72.7  275   9  5   9.6   5.3
  7000  22.7  72.9  255   9  5   9.9   5.4 |  23.3  73.9  275   9  5   9.4   5.1
  6750  23.5  74.3  255   9  5   9.8   5.4 |  23.9  75.0  280   9  4   8.9   4.9
  6500  24.2  75.6  255   9  5  10.6   5.8 |  24.6  76.3  280   8  4   9.6   5.2
  6250  25.0  77.0  260   9  4  11.6   6.3 |  25.4  77.7  280   8  4  10.1   5.6
  6000  25.8  78.4  260   8  4  10.0   5.5 |  26.1  79.0  280   8  4  10.0   5.5
  5750  26.5  79.7  260   8  4  10.4   5.7 |  26.8  80.2  285   7  4   9.2   5.0
  5500  27.4  81.3  260   8  4  13.6   7.5 |  27.4  81.3  285   7  4   7.4   4.0
  5250  28.4  83.1  260   8  4  14.0   7.7 |  27.9  82.2  285   7  4   6.3   3.5
  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 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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