Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 241246
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0644 MDT Sunday, July 24, 2016

This forecast is for Sunday, July 24, 2016:

If the trigger temperature of 87.6 F/30.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1538 ft/min (7.8 m/s)
   Maximum height of thermals.................. 22797 ft MSL (17958 ft AGL)

Forecast maximum temperature................... 100.0 F/38.2 C
Time of trigger temperature.................... 1115 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................. 15448 ft MSL (10609 ft AGL)
Thermal soaring outlook for Monday 07/25....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:08:12 / 20:33:19 MDT
Total possible sunshine........... 14 hr 25 min 7 sec (865 min 7 sec)
Altitude of sun at 13:20:36 MDT... 70.50 degrees

Upper air data from rawinsonde observation taken on 07/24/2016 at 0600 MDT

Freezing level.................. 16607 ft MSL (11768 ft AGL)
Convective condensation level... 17896 ft MSL (13057 ft AGL)
Lifted condensation level....... 18939 ft MSL (14100 ft AGL)
Lifted index.................... -4.6
K index......................... +24.6

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  -64.4 -83.9   275   20   10   5.5   3.0   85.4 185.7    27.7      M    M
 45000  -58.1 -72.6   275   30   15   6.1   3.3   71.5 160.7    21.1      M    M
 40000  -51.7 -61.1   240   61   31   6.8   3.7   58.8 137.8    14.0      M    M
 38000  -47.3 -53.1   235   60   31   8.7   4.8   56.6 133.9    12.9      M    M
 36000  -42.4 -44.3   240   57   29   5.0   2.8   54.2 129.5    11.6      M    M
 34000  -38.4 -37.1   240   49   25   5.6   3.1   51.6 124.9    10.0      M    M
 32000  -33.8 -28.8   245   41   21   8.3   4.5   49.8 121.7     8.9      M    M
 30000  -29.1 -20.4   235   38   20   8.1   4.4   48.4 119.1     8.0      M    M
 29000  -26.3 -15.3   240   35   18   9.9   5.4   48.1 118.6     7.9      M    M
 28000  -24.4 -11.9   245   32   16   6.0   3.3   46.9 116.5     7.0      M    M
 27000  -22.0  -7.6   250   29   15   3.6   2.0   46.1 114.9     6.5      M    M
 26000  -21.9  -7.4   255   27   14  -4.3  -2.4   42.6 108.7     3.8      M    M
 25000  -20.2  -4.4   265   25   13   7.6   4.2   41.0 105.8     2.6      M    M
 24000  -18.2  -0.8   265   23   12   4.7   2.6   39.9 103.9     1.7      M    M
 23000  -16.7   1.9   270   21   11   6.5   3.6   38.3 100.9     0.3      M    M
 22000  -14.7   5.5   270   20   10   7.6   4.2   37.3  99.1    -0.7   1674  8.5
 21000  -12.2  10.0   270   18    9   8.5   4.7   36.8  98.2    -1.2   1571  8.0
 20000   -9.9  14.2   275   16    8   7.6   4.2   36.3  97.3    -1.7   1470  7.5
 19500   -8.7  16.3   280   16    8  10.5   5.7   36.0  96.7    -2.1   1421  7.2
 19000   -6.5  20.3   280   16    8   9.5   5.2   36.1  96.9    -2.0   1331  6.8
 18500   -5.1  22.8   285   17    9   9.4   5.2   36.0  96.9    -2.1   1274  6.5
 18000   -3.7  25.3   285   17    9   9.4   5.2   36.0  96.8    -2.1   1218  6.2
 17500   -2.3  27.9   275   16    8   9.4   5.2   36.0  96.7    -2.2   1161  5.9
 17000   -0.9  30.4   270   16    8   9.4   5.2   35.9  96.6    -2.3   1104  5.6
 16500    0.5  32.9   280   15    8   9.5   5.2   35.8  96.5    -2.4   1047  5.3
 16000    1.8  35.2   285   15    8   7.6   4.2   35.7  96.2    -2.5    993  5.0
 15500    2.8  37.0   280   14    7   8.2   4.5   35.2  95.4    -3.0    949  4.8
 15000    4.2  39.6   275   13    7   9.0   4.9   35.1  95.2    -3.2    894  4.5
 14500    5.5  41.9   270   12    6   9.1   5.0   35.0  95.0    -3.3    839  4.3
 14000    6.9  44.4   265   11    6   9.1   5.0   34.9  94.9    -3.4    784  4.0
 13500    8.1  46.6   255    9    5   7.6   4.2   34.8  94.6    -3.6    730  3.7
 13000    9.2  48.6   245    8    4   7.0   3.8   34.3  93.7    -4.1    685  3.5
 12500   10.2  50.4   235    7    3   6.9   3.8   33.9  92.9    -4.5    639  3.2
 12000   11.2  52.2   215    6    3   6.9   3.8   33.4  92.2    -4.9    593  3.0
 11500   12.3  54.1   180    3    1   6.9   3.8   33.0  91.3    -5.4    548  2.8
 11000   13.3  55.9   105    3    2   6.9   3.8   32.5  90.5    -5.9    502  2.5
 10500   14.3  57.7   080    7    3   7.0   3.8   32.1  89.7    -6.3    456  2.3
 10250   14.9  58.8   075    8    4   8.7   4.8   31.9  89.4    -6.5    432  2.2
 10000   15.6  60.1   075    9    5   9.9   5.4   31.9  89.4    -6.5    403  2.0
  9750   16.3  61.3   070   11    6   9.6   5.3   31.9  89.4    -6.5    374  1.9
  9500   17.0  62.6   070   12    6   9.7   5.3   31.9  89.4    -6.6    345  1.8
  9250   17.8  64.0   065   13    7   9.6   5.3   31.9  89.4    -6.6    316  1.6
  9000   18.5  65.3   065   15    8   9.6   5.3   31.9  89.4    -6.6    287  1.5
  8750   19.2  66.6   060   15    8   9.6   5.3   31.9  89.4    -6.6    258  1.3
  8500   19.9  67.8   060   15    8   9.7   5.3   31.9  89.3    -6.7    229  1.2
  8250   20.6  69.1   055   15    8   9.5   5.2   31.9  89.3    -6.7    201  1.0
  8000   21.3  70.3   050   15    8  10.0   5.5   31.8  89.3    -6.7    172  0.9
  7750   22.1  71.8   060   16    8   8.1   4.5   31.8  89.3    -6.8    143  0.7
  7500   22.4  72.3   065   17    9   0.9   0.5   31.4  88.6    -7.2    125  0.6
  7250   22.4  72.3   075   19   10   4.2   2.3   30.7  87.3    -7.9    118  0.6
  7000   23.1  73.6   080   21   11  10.7   5.8   30.7  87.2    -8.0     91  0.5
  6750   23.8  74.8   080   20   10   9.9   5.4   30.7  87.2    -8.0     61  0.3
  6500   24.5  76.1   085   19   10   9.6   5.2   30.7  87.3    -8.0     31  0.2
  6250   25.2  77.4   085   18    9   6.8   3.7   30.6  87.1    -8.1      5  0.0
  6000   25.6  78.1   090   16    8   5.6   3.1   30.3  86.5    -8.5      M    M
  5750   26.0  78.8   090   15    8   5.5   3.0   30.0  86.0    -8.8      M    M
  5500   26.4  79.5   095   13    7   7.0   3.8   29.7  85.5    -9.2      M    M
  5250   26.8  80.2   095   11    6   1.1   0.6   29.4  84.9    -9.5      M    M
  5000   26.2  79.2   100    9    5 -17.9  -9.8   28.1  82.5   -10.9      M    M

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

           07/24/2016 at 0900 MDT          |       07/24/2016 at 1200 MDT
                                           |
K index... +28.7  LI... +271.1             | K index... +29.2  LI... +270.2
CAPE... +332.1  CIN... -20.2               | CAPE... +542.8  CIN... -40.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.0 -83.2  265  14  7   1.8   1.0 | -64.0 -83.2  250  18  9   1.7   0.9
 45000 -59.1 -74.4  260  28 14   5.6   3.0 | -59.2 -74.6  255  32 16   5.8   3.2
 40000 -50.6 -59.1  255  45 23   6.2   3.4 | -50.4 -58.7  255  43 22   5.9   3.3
 38000 -46.9 -52.4  250  46 23   6.2   3.4 | -46.9 -52.4  250  43 22   5.9   3.3
 36000 -43.1 -45.6  250  46 24   6.3   3.5 | -43.3 -45.9  250  43 22   6.2   3.4
 34000 -38.8 -37.8  255  41 21   7.4   4.0 | -38.8 -37.8  255  38 20   7.7   4.2
 32000 -34.3 -29.7  260  37 19   7.3   4.0 | -33.6 -28.5  260  33 17   7.7   4.2
 30000 -29.3 -20.7  260  32 17   7.5   4.1 | -29.0 -20.2  260  29 15   7.6   4.2
 29000 -27.0 -16.6  260  31 16   7.6   4.1 | -26.7 -16.1  260  27 14   7.7   4.2
 28000 -24.9 -12.8  260  29 15   4.7   2.6 | -24.6 -12.3  260  26 13   4.4   2.4
 27000 -23.4 -10.1  265  29 15   5.0   2.8 | -23.2  -9.8  265  26 13   4.7   2.6
 26000 -21.9  -7.4  265  28 14   5.1   2.8 | -21.8  -7.2  265  25 13   4.7   2.6
 25000 -20.4  -4.7  265  28 14   5.9   3.3 | -20.4  -4.7  265  25 13   6.0   3.3
 24000 -18.4  -1.1  265  27 14   6.8   3.7 | -18.3  -0.9  265  25 13   7.1   3.9
 23000 -16.5   2.3  265  27 14   7.0   3.8 | -16.2   2.8  265  24 13   7.3   4.0
 22000 -14.4   6.1  265  26 13   8.2   4.5 | -14.1   6.6  260  24 12   8.3   4.5
 21000 -11.9  10.6  270  23 12   8.7   4.8 | -11.6  11.1  260  21 11   8.6   4.7
 20000  -9.3  15.3  270  21 11   8.7   4.8 |  -9.1  15.6  260  18 10   8.7   4.8
 19500  -8.0  17.6  270  19 10   8.7   4.8 |  -7.9  17.8  260  17  9   8.6   4.7
 19000  -6.7  19.9  270  18  9   8.8   4.8 |  -6.6  20.1  260  16  8   8.5   4.6
 18500  -5.4  22.3  265  18  9   8.8   4.9 |  -5.4  22.3  260  15  8   8.4   4.6
 18000  -4.1  24.6  265  17  9   9.0   4.9 |  -4.1  24.6  260  15  8   9.4   5.1
 17500  -2.8  27.0  260  17  9   9.1   5.0 |  -2.7  27.1  255  15  8   9.5   5.2
 17000  -1.5  29.3  260  17  9   9.2   5.1 |  -1.3  29.7  255  15  8   9.5   5.2
 16500  -0.1  31.8  255  17  9   9.8   5.4 |   0.1  32.2  255  15  8   9.4   5.2
 16000   1.3  34.3  255  16  8   9.8   5.4 |   1.5  34.7  250  15  8   9.5   5.2
 15500   2.7  36.9  250  16  8   9.1   5.0 |   3.5  38.3  250  15  8   9.1   5.0
 15000   4.6  40.3  245  14  7   9.1   5.0 |   4.8  40.6  245  15  8   9.1   5.0
 14500   6.0  42.8  245  13  7   9.6   5.3 |   6.2  43.2  245  15  7   9.5   5.2
 14000   7.4  45.3  240  12  6   9.6   5.3 |   7.6  45.7  245  14  7   9.5   5.2
 13500   8.7  47.7  235  11  6   8.9   4.9 |   9.0  48.2  240  14  7   9.4   5.1
 13000  10.0  50.0  235  10  5   8.8   4.8 |  10.3  50.5  240  13  7   9.4   5.2
 12500  11.3  52.3  230   9  5   8.9   4.9 |  11.7  53.1  235  12  6   8.8   4.8
 12000  12.7  54.9  225   8  4   8.9   4.9 |  13.0  55.4  235  11  5   8.6   4.7
 11500  14.0  57.2  215   8  4   8.5   4.7 |  14.3  57.7  235  10  5   8.8   4.8
 11000  15.2  59.4  210   7  4   8.2   4.5 |  15.6  60.1  230   9  5   9.2   5.0
 10500  16.4  61.5  200   7  4   5.1   2.8 |  16.7  62.1  230   8  4   5.2   2.9
 10250  16.7  62.1  195   7  4   6.5   3.6 |  17.2  63.0  230   8  4   8.2   4.5
 10000  17.4  63.3  195   8  4  10.0   5.5 |  17.9  64.2  230   8  4  11.0   6.0
  9750  18.1  64.6  190   8  4   9.5   5.2 |  18.7  65.7  230   8  4  10.5   5.8
  9500  18.8  65.8  185   8  4   7.4   4.1 |  19.4  66.9  225   8  4   7.5   4.1
  9250  19.3  66.7  185   8  4   6.7   3.7 |  19.8  67.6  225   7  4   6.9   3.8
  9000  19.9  67.8  180   8  4   8.5   4.7 |  20.5  68.9  225   7  4   9.2   5.1
  8750  20.5  68.9  180   9  5   8.3   4.5 |  21.1  70.0  220   7  4   8.6   4.7
  8500  21.1  70.0  175   9  5   7.0   3.8 |  21.7  71.1  215   7  3   7.9   4.3
  8250  21.5  70.7  170  10  5   5.9   3.2 |  22.3  72.1  210   6  3   7.4   4.1
  8000  22.0  71.6  170  10  5   5.6   3.1 |  22.8  73.0  205   6  3   7.5   4.1
  7750  22.4  72.3  165  10  5   4.8   2.6 |  23.4  74.1  205   5  3   8.0   4.4
  7500  22.7  72.9  160  10  5   3.4   1.9 |  24.0  75.2  200   5  3   9.5   5.2
  7250  22.9  73.2  160  10  5   2.8   1.5 |  24.7  76.5  200   5  3   9.9   5.5
  7000  23.1  73.6  155   9  5   2.4   1.3 |  25.5  77.9  200   5  3  10.1   5.5
  6750  23.2  73.8  150   9  4   1.5   0.8 |  26.2  79.2  200   5  3  10.7   5.8
  6500  23.3  73.9  150   8  4   1.3   0.7 |  27.0  80.6  205   5  3  10.7   5.9
  6250  23.3  73.9  145   7  4   1.9   1.0 |  27.8  82.0  205   5  3  10.9   6.0
  6000  23.4  74.1  135   6  3  -0.2  -0.1 |  28.6  83.5  205   5  3  10.0   5.5
  5750  23.3  73.9  125   5  2   5.0   2.7 |  29.4  84.9  205   5  2  12.5   6.8
  5500  24.0  75.2  125   4  2  12.2   6.7 |  30.5  86.9  205   5  2  15.7   8.6
  5250  24.8  76.6  120   4  2   6.5   3.6 |  31.6  88.9  210   5  2  13.2   7.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/24/2016 at 1500 MDT          |       07/24/2016 at 1800 MDT
                                           |
K index... +24.7  LI... +270.9             | K index... +11.4  LI... +274.1
CAPE... +391.3  CIN... -25.3               | CAPE... +20.0  CIN... -72.6
                                           |
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 -64.4 -83.9  250  22 11   1.6   0.9 | -64.6 -84.3  255  21 11   1.5   0.8
 45000 -59.6 -75.3  250  33 17   6.0   3.3 | -59.9 -75.8  250  32 16   6.0   3.3
 40000 -50.2 -58.4  255  40 20   6.0   3.3 | -50.3 -58.5  255  37 19   6.4   3.5
 38000 -46.6 -51.9  250  39 20   6.0   3.3 | -46.5 -51.7  250  36 19   6.4   3.5
 36000 -43.0 -45.4  250  39 20   7.1   3.9 | -42.6 -44.7  245  35 18   7.3   4.0
 34000 -38.3 -36.9  250  34 17   7.8   4.3 | -38.0 -36.4  245  31 16   7.8   4.3
 32000 -33.6 -28.5  250  29 15   7.9   4.3 | -33.3 -27.9  245  26 13   7.9   4.3
 30000 -28.9 -20.0  250  25 13   8.0   4.4 | -28.6 -19.5  245  23 12   8.0   4.4
 29000 -26.5 -15.7  250  23 12   8.0   4.4 | -26.2 -15.2  245  22 11   8.0   4.4
 28000 -24.2 -11.6  250  22 11   6.3   3.5 | -23.9 -11.0  245  20 10   5.9   3.3
 27000 -22.3  -8.1  250  21 11   6.3   3.4 | -21.7  -7.1  250  19 10   5.9   3.3
 26000 -20.0  -4.0  250  20 10   6.3   3.4 | -19.9  -3.8  250  18  9   5.9   3.3
 25000 -18.1  -0.6  255  19 10   6.0   3.3 | -18.1  -0.6  255  17  9   6.7   3.7
 24000 -16.4   2.5  255  19 10   6.0   3.3 | -16.1   3.0  260  17  9   6.8   3.7
 23000 -14.6   5.7  255  19 10   6.0   3.3 | -14.1   6.6  265  18  9   6.8   3.7
 22000 -12.7   9.1  260  19 10   7.8   4.3 | -12.0  10.4  265  19 10   8.3   4.6
 21000 -10.5  13.1  260  19 10   7.9   4.3 |  -9.5  14.9  265  19 10   8.4   4.6
 20000  -8.2  17.2  260  19 10   8.1   4.5 |  -7.0  19.4  265  19 10   8.4   4.6
 19500  -7.0  19.4  260  19 10   8.4   4.6 |  -5.8  21.6  265  19 10   8.4   4.6
 19000  -5.8  21.6  260  19 10   8.7   4.8 |  -4.5  23.9  265  19 10   8.5   4.6
 18500  -4.5  23.9  260  19 10   8.8   4.8 |  -3.3  26.1  265  19 10   8.5   4.6
 18000  -3.3  26.1  265  18  9   8.9   4.9 |  -2.0  28.4  265  18  9   8.7   4.8
 17500  -2.0  28.4  265  18  9   8.9   4.9 |  -0.7  30.7  265  18  9   8.7   4.8
 17000  -0.7  30.7  265  17  9   9.0   4.9 |   0.6  33.1  270  17  9   8.7   4.8
 16500   0.6  33.1  270  17  9   9.1   5.0 |   1.8  35.2  270  17  9   8.7   4.8
 16000   2.0  35.6  270  17  8   9.2   5.0 |   3.1  37.6  270  16  8   8.7   4.8
 15500   3.3  37.9  270  16  8   8.9   4.9 |   4.3  39.7  270  15  8   8.7   4.8
 15000   4.6  40.3  270  16  8   8.9   4.9 |   5.6  42.1  275  15  8   8.7   4.8
 14500   6.0  42.8  270  15  8   9.6   5.2 |   6.9  44.4  275  14  7   9.1   5.0
 14000   7.4  45.3  270  15  8   9.7   5.3 |   8.3  46.9  280  14  7   9.2   5.0
 13500   8.8  47.8  270  14  7   9.6   5.3 |   9.6  49.3  280  13  7   8.9   4.9
 13000  10.9  51.6  265  13  7   9.4   5.2 |  11.5  52.7  285  12  6   8.5   4.7
 12500  12.3  54.1  265  13  7   9.2   5.1 |  12.8  55.0  290  12  6   9.2   5.0
 12000  13.6  56.5  265  12  6   9.2   5.1 |  14.2  57.6  290  12  6   9.3   5.1
 11500  15.0  59.0  265  12  6   8.8   4.8 |  15.5  59.9  295  12  6   8.9   4.9
 11000  16.2  61.2  265  11  6   9.4   5.2 |  16.8  62.2  295  11  6   9.3   5.1
 10500  17.2  63.0  265  10  5   5.4   3.0 |  17.8  64.0  300  11  6   5.7   3.1
 10250  17.8  64.0  265   9  5  10.3   5.7 |  18.4  65.1  300  11  6  10.0   5.5
 10000  18.5  65.3  265   9  5  10.4   5.7 |  19.1  66.4  300  11  5  10.1   5.5
  9750  19.3  66.7  265   8  4  10.4   5.7 |  19.9  67.8  300  10  5  10.4   5.7
  9500  20.0  68.0  265   8  4   7.8   4.3 |  20.6  69.1  305  10  5   7.8   4.3
  9250  20.5  68.9  265   8  4   7.6   4.2 |  21.1  70.0  305  10  5   7.6   4.2
  9000  21.1  70.0  265   7  4   9.4   5.2 |  21.7  71.1  305   9  5   9.7   5.3
  8750  21.8  71.2  265   7  4   9.0   4.9 |  22.4  72.3  305   9  4   9.2   5.0
  8500  22.4  72.3  270   7  3   9.9   5.4 |  23.0  73.4  305   8  4   9.0   5.0
  8250  23.2  73.8  270   7  3  10.2   5.6 |  23.7  74.7  305   8  4   9.0   5.0
  8000  23.9  75.0  270   7  3   9.9   5.4 |  24.3  75.7  305   8  4   9.8   5.4
  7750  24.6  76.3  270   7  3   9.9   5.4 |  25.0  77.0  305   7  4  10.0   5.5
  7500  25.3  77.5  270   7  3  10.0   5.5 |  25.8  78.4  300   7  4   9.9   5.4
  7250  26.1  79.0  270   7  3  10.1   5.5 |  26.5  79.7  300   7  4  10.0   5.5
  7000  26.8  80.2  270   7  3  10.2   5.6 |  27.2  81.0  300   7  4   9.5   5.2
  6750  27.6  81.7  270   7  3  10.6   5.8 |  28.0  82.4  300   7  4   9.8   5.4
  6500  28.4  83.1  270   7  3  10.8   5.9 |  28.7  83.7  300   7  4  10.6   5.8
  6250  29.2  84.6  270   7  3  11.2   6.1 |  29.5  85.1  295   7  4  11.1   6.1
  6000  30.0  86.0  270   7  3   9.8   5.4 |  30.4  86.7  295   7  4  10.0   5.5
  5750  30.8  87.4  270   6  3  12.6   6.9 |  31.0  87.8  295   7  3  10.2   5.6
  5500  31.9  89.4  270   7  3  16.9   9.2 |  31.8  89.2  295   7  3  11.6   6.4
  5250  33.1  91.6  270   7  3  13.5   7.4 |  32.6  90.7  300   6  3  10.5   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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