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239
UXUS97 KGJT 311235
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0635 MDT Sunday, August 31, 2014

This forecast is for Sunday, August 31, 2014:

If the trigger temperature of 82.2 F/27.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 630 ft/min (3.2 m/s)
   Maximum height of thermals.................. 15894 ft MSL (11055 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1145 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................. 8510 ft MSL (3671 ft AGL)
Thermal soaring outlook for Monday 09/01....... Good

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

Remarks...

Sunrise/Sunset.................... 06:41:56 / 19:47:31 MDT
Total possible sunshine........... 13 hr 5 min 35 sec (785 min 35 sec)
Altitude of sun at 13:14:18 MDT... 59.34 degrees

Upper air data from rawinsonde observation taken on 08/31/2014 at 0600 MDT

Freezing level.................. 14985 ft MSL (10146 ft AGL)
Convective condensation level... 17033 ft MSL (12194 ft AGL)
Lifted condensation level....... 16952 ft MSL (12113 ft AGL)
Lifted index.................... +0.1
K index......................... +21.2

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  -61.1 -78.0   260   44   23   6.5   3.6   93.4 200.1    36.4      M    M
 45000  -57.1 -70.8   265   68   35   0.9   0.5   75.6 168.0    27.9      M    M
 40000  -53.7 -64.7   275   92   47   1.0   0.6   58.1 136.5    18.2      M    M
 38000  -52.2 -62.0   275   89   46   2.5   1.4   50.4 122.8    13.6      M    M
 36000  -48.5 -55.3   275   87   45   7.2   4.0   47.4 117.2    11.8      M    M
 34000  -44.3 -47.7   270   85   44   9.3   5.1   45.1 113.1    10.4      M    M
 32000  -38.9 -38.0   265   83   43   8.5   4.7   44.4 111.8    10.2      M    M
 30000  -34.5 -30.1   265   75   39   6.4   3.5   42.5 108.6     9.0      M    M
 29000  -32.0 -25.6   265   70   36   8.2   4.5   41.8 107.3     8.5      M    M
 28000  -29.6 -21.3   265   64   33   8.1   4.5   41.2 106.2     8.2      M    M
 27000  -27.1 -16.8   265   59   30   8.7   4.8   40.8 105.4     7.9      M    M
 26000  -24.5 -12.1   265   53   27   8.7   4.8   40.4 104.8     7.7      M    M
 25000  -21.9  -7.4   265   54   28   8.8   4.8   40.0 104.1     7.4      M    M
 24000  -19.5  -3.1   265   49   25   7.4   4.0   39.4 103.0     7.0      M    M
 23000  -17.5   0.5   260   46   24   6.4   3.5   38.2 100.8     6.0      M    M
 22000  -15.6   3.9   255   43   22   5.9   3.2   37.1  98.7     5.1      M    M
 21000  -14.9   5.2   245   40   21   6.0   3.3   34.4  94.0     2.9      M    M
 20000  -12.8   9.0   240   38   19   8.8   4.8   32.7  90.9     1.4      M    M
 19500  -11.5  11.3   240   37   19   8.7   4.8   32.5  90.5     1.2      M    M
 19000  -10.3  13.5   240   36   19   8.8   4.8   32.4  90.2     1.1      M    M
 18500   -9.1  15.6   245   36   19   8.1   4.4   32.1  89.7     0.8      M    M
 18000   -7.8  18.0   250   37   19   8.8   4.8   31.8  89.3     0.6      M    M
 17500   -6.5  20.3   250   37   19   8.8   4.8   31.7  89.0     0.4      M    M
 17000   -5.2  22.6   255   38   19   8.8   4.8   31.5  88.7     0.3      M    M
 16500   -3.9  25.0   255   38   20   8.8   4.8   31.4  88.5     0.1      M    M
 16000   -2.6  27.3   260   39   20   8.8   4.8   31.3  88.3     0.0      M    M
 15500   -1.2  29.8   265   38   20   8.9   4.9   31.1  87.9    -0.1    980  5.0
 15000    0.1  32.2   265   37   19   8.9   4.9   30.9  87.7    -0.3    925  4.7
 14500    1.4  34.5   270   37   19   8.9   4.9   30.8  87.5    -0.4    871  4.4
 14000    2.8  37.0   270   36   18   8.9   4.9   30.7  87.3    -0.5    816  4.1
 13500    4.1  39.4   270   35   18   8.9   4.9   30.5  87.0    -0.6    761  3.9
 13000    5.5  41.9   265   34   18   8.9   4.9   30.4  86.7    -0.8    706  3.6
 12500    6.8  44.2   265   34   17   9.0   4.9   30.3  86.5    -0.9    651  3.3
 12000    8.1  46.6   260   33   17   9.0   5.0   30.2  86.3    -1.0    596  3.0
 11500    9.5  49.1   255   33   17   9.0   5.0   30.0  86.0    -1.2    541  2.7
 11000   10.8  51.4   255   32   17   9.0   5.0   29.9  85.8    -1.3    486  2.5
 10500   12.2  54.0   250   32   17   9.0   5.0   29.8  85.6    -1.4    431  2.2
 10250   12.8  55.0   250   32   16   9.1   5.0   29.7  85.5    -1.5    403  2.0
 10000   13.5  56.3   250   33   17   8.9   4.9   29.7  85.4    -1.5    376  1.9
  9750   14.2  57.6   250   31   16   9.4   5.1   29.6  85.3    -1.6    348  1.8
  9500   14.8  58.6   250   28   15   7.8   4.3   29.6  85.2    -1.7    321  1.6
  9250   15.3  59.5   245   26   13   5.5   3.0   29.3  84.8    -1.9    300  1.5
  9000   15.7  60.3   245   23   12   5.4   2.9   29.0  84.1    -2.3    280  1.4
  8750   16.1  61.0   245   22   11   5.4   3.0   28.6  83.5    -2.6    261  1.3
  8500   16.5  61.7   245   21   11   5.4   3.0   28.3  82.9    -3.0    242  1.2
  8250   16.9  62.4   250   19   10   5.4   3.0   27.9  82.3    -3.3    222  1.1
  8000   17.3  63.1   250   18    9   7.6   4.2   27.7  81.8    -3.6    201  1.0
  7750   18.0  64.4   255   16    8   9.2   5.1   27.6  81.7    -3.7    174  0.9
  7500   18.6  65.5   260   14    7   8.8   4.8   27.5  81.6    -3.8    147  0.7
  7250   19.3  66.7   270   12    6   8.9   4.9   27.5  81.5    -3.8    120  0.6
  7000   19.9  67.8   285   10    5   8.9   4.9   27.4  81.4    -3.9     93  0.5
  6750   20.6  69.1   290   10    5   8.9   4.9   27.4  81.2    -4.0     66  0.3
  6500   21.3  70.3   285    9    5   9.0   4.9   27.3  81.1    -4.1     39  0.2
  6250   21.9  71.4   280    9    4   7.0   3.8   27.2  80.9    -4.2     14  0.1
  6000   22.2  72.0   275    8    4   4.3   2.3   26.9  80.3    -4.6      M    M
  5750   22.6  72.7   275    6    3   8.2   4.5   26.5  79.7    -4.9      M    M
  5500   23.0  73.4   285    3    2  -7.1  -3.9   26.1  79.0    -5.4      M    M
  5250   21.5  70.7   360    1    0 -18.9 -10.4   24.1  75.3    -7.5      M    M
  5000   20.8  69.4   070    3    2   5.5   3.0   22.7  72.9    -9.0      7  0.0

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

           08/31/2014 at 0900 MDT          |       08/31/2014 at 1200 MDT
                                           |
K index... +19.8  LI... +0.7               | K index... +22.5  LI... -0.2
CAPE... 0.0  CIN... -25.2                  | CAPE... 0.0  CIN... -90.5
                                           |
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 -61.3 -78.3  280  38 20   2.1   1.2 | -61.6 -78.9  280  35 18   3.5   1.9
 45000 -57.8 -72.0  280  62 32   3.0   1.7 | -56.4 -69.5  285  58 30   3.4   1.8
 40000 -53.2 -63.8  280  85 44   4.1   2.3 | -51.4 -60.5  290  86 44   3.1   1.7
 38000 -50.4 -58.7  285  87 45   4.7   2.6 | -49.6 -57.3  290  86 44   3.0   1.6
 36000 -47.6 -53.7  285  90 46   4.7   2.6 | -47.8 -54.0  290  87 45   2.9   1.6
 34000 -43.9 -47.0  285  89 46   7.0   3.8 | -43.9 -47.0  290  86 44   7.2   4.0
 32000 -39.2 -38.6  285  85 44   7.0   3.9 | -39.5 -39.1  290  85 44   7.3   4.0
 30000 -34.7 -30.5  285  80 41   7.7   4.2 | -34.9 -30.8  290  78 40   7.9   4.4
 29000 -32.4 -26.3  285  77 39   7.7   4.2 | -32.5 -26.5  290  72 37   7.9   4.4
 28000 -30.0 -22.0  285  74 38   7.7   4.2 | -30.2 -22.4  290  67 34   8.0   4.4
 27000 -27.7 -17.9  285  69 36   7.7   4.2 | -27.9 -18.2  290  64 33   7.5   4.1
 26000 -25.4 -13.7  280  65 33   7.7   4.2 | -25.6 -14.1  285  62 32   7.5   4.1
 25000 -23.2  -9.8  280  60 31   7.7   4.2 | -23.3  -9.9  285  60 31   7.5   4.1
 24000 -21.2  -6.2  275  56 29   5.7   3.1 | -21.1  -6.0  285  58 30   7.5   4.1
 23000 -19.6  -3.3  275  51 26   5.7   3.1 | -18.8  -1.8  280  56 29   7.6   4.2
 22000 -17.9  -0.2  270  46 24   5.6   3.0 | -16.6   2.1  275  54 28   7.7   4.2
 21000 -15.7   3.7  270  44 23   8.4   4.6 | -14.6   5.7  270  53 27   6.3   3.4
 20000 -13.2   8.2  265  44 23   8.5   4.6 | -12.8   9.0  270  52 27   6.3   3.5
 19500 -12.0  10.4  265  44 23   8.5   4.6 | -11.9  10.6  265  51 26   6.4   3.5
 19000 -10.8  12.6  265  44 23   8.3   4.6 | -11.0  12.2  265  51 26   7.5   4.1
 18500  -9.6  14.7  260  44 22   8.2   4.5 |  -9.7  14.5  265  50 26   8.6   4.7
 18000  -8.4  16.9  260  43 22   8.0   4.4 |  -8.4  16.9  265  50 26   8.8   4.8
 17500  -7.1  19.2  255  43 22  10.0   5.5 |  -7.2  19.0  265  50 26   8.0   4.4
 17000  -5.6  21.9  255  42 22   9.8   5.4 |  -6.1  21.0  260  49 25   8.1   4.5
 16500  -4.1  24.6  255  42 21   9.2   5.1 |  -4.9  23.2  260  49 25   9.2   5.0
 16000  -2.8  27.0  255  41 21   8.8   4.8 |  -2.7  27.1  260  47 24  10.0   5.5
 15500  -0.9  30.4  255  39 20   8.4   4.6 |  -1.3  29.7  260  46 24   8.7   4.8
 15000   0.4  32.7  255  38 19   8.3   4.5 |  -0.0  32.0  260  44 23   8.4   4.6
 14500   1.6  34.9  255  36 18   8.4   4.6 |   1.2  34.2  265  43 22   7.9   4.3
 14000   2.9  37.2  255  36 18   8.5   4.6 |   2.3  36.1  265  40 20   7.2   4.0
 13500   4.1  39.4  255  35 18   8.4   4.6 |   3.4  38.1  265  37 19   7.0   3.8
 13000   5.3  41.5  255  35 18   7.9   4.4 |   4.4  39.9  265  33 17   6.1   3.3
 12500   6.5  43.7  260  34 18   8.0   4.4 |   5.3  41.5  265  29 15   6.2   3.4
 12000   7.6  45.7  260  32 17   7.2   4.0 |   6.3  43.3  265  25 13   7.7   4.2
 11500   8.7  47.7  260  30 15   7.4   4.0 |   7.4  45.3  265  22 11   7.7   4.2
 11000   9.7  49.5  260  28 14   6.3   3.5 |   8.5  47.3  265  20 10   7.3   4.0
 10500  10.6  51.1  260  26 13   8.7   4.8 |   9.5  49.1  270  18  9  10.0   5.5
 10250  11.3  52.3  260  25 13   8.7   4.7 |  10.4  50.7  270  17  9  10.9   6.0
 10000  11.8  53.2  260  24 12   5.6   3.1 |  11.0  51.8  270  17  9   7.9   4.3
  9750  12.3  54.1  260  23 12   6.4   3.5 |  11.6  52.9  265  16  8   8.7   4.8
  9500  12.7  54.9  260  22 11   6.2   3.4 |  12.3  54.1  265  16  8   8.3   4.5
  9250  13.2  55.8  260  21 11   5.6   3.1 |  12.9  55.2  265  16  8   7.1   3.9
  9000  13.6  56.5  260  20 10   5.7   3.1 |  13.4  56.1  265  16  8   6.9   3.8
  8750  14.0  57.2  260  20 10   6.2   3.4 |  13.9  57.0  265  15  8   7.5   4.1
  8500  14.4  57.9  260  19 10   6.1   3.3 |  14.4  57.9  265  15  7   7.3   4.0
  8250  14.9  58.8  260  18  9   6.8   3.7 |  15.0  59.0  265  14  7   7.1   3.9
  8000  15.4  59.7  260  18  9   6.0   3.3 |  15.4  59.7  270  12  6   6.7   3.7
  7750  15.8  60.4  260  17  9   5.0   2.8 |  15.9  60.6  270  11  6   6.0   3.3
  7500  16.2  61.2  260  17  9   5.2   2.9 |  16.4  61.5  275   9  5   7.5   4.1
  7250  16.6  61.9  255  15  8   5.1   2.8 |  17.0  62.6  275   9  5   9.6   5.3
  7000  16.9  62.4  255  13  7   4.8   2.6 |  17.7  63.9  275   9  4   9.8   5.4
  6750  17.2  63.0  250  11  6   4.7   2.6 |  18.5  65.3  275   8  4  10.0   5.5
  6500  17.6  63.7  240   9  5   3.4   1.9 |  19.2  66.6  275   8  4  10.6   5.8
  6250  17.7  63.9  235   8  4   2.4   1.3 |  20.0  68.0  275   8  4  11.3   6.2
  6000  17.8  64.0  220   6  3   2.5   1.4 |  20.9  69.6  275   8  4  10.4   5.7
  5750  18.0  64.4  205   5  3   4.0   2.2 |  21.6  70.9  275   8  4  10.9   6.0
  5500  18.4  65.1  200   5  2   7.2   3.9 |  22.5  72.5  275   8  4  13.7   7.5
  5250  18.9  66.0  205   5  2   8.0   4.4 |  23.6  74.5  275   8  4  14.7   8.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/31/2014 at 1500 MDT          |       08/31/2014 at 1800 MDT
                                           |
K index... +15.6  LI... +0.6               | K index... +17.1  LI... +1.0
CAPE... 0.0  CIN... -1.9                   | CAPE... 0.0  CIN... M
                                           |
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 -62.4 -80.3  290  39 20   3.6   2.0 | -63.4 -82.1  300  42 22   3.2   1.8
 45000 -57.3 -71.1  300  62 32   2.7   1.5 | -58.7 -73.7  310  63 32   2.8   1.6
 40000 -52.8 -63.0  305  88 45   6.0   3.3 | -53.8 -64.8  300  78 40   6.9   3.8
 38000 -49.3 -56.7  305  92 48   5.8   3.2 | -49.7 -57.5  305  80 41   6.8   3.7
 36000 -45.9 -50.6  305  97 50   5.8   3.2 | -45.7 -50.3  305  82 42   6.8   3.7
 34000 -41.8 -43.2  305  94 48   7.1   3.9 | -41.2 -42.2  305  82 42   7.8   4.3
 32000 -37.6 -35.7  300  89 46   7.1   3.9 | -36.5 -33.7  300  82 42   7.8   4.3
 30000 -33.3 -27.9  300  81 42   7.2   3.9 | -31.7 -25.1  300  79 41   8.1   4.4
 29000 -31.2 -24.2  300  77 40   7.2   3.9 | -29.3 -20.7  300  77 39   8.1   4.4
 28000 -29.0 -20.2  295  72 37   7.2   4.0 | -26.9 -16.4  300  74 38   8.4   4.6
 27000 -27.0 -16.6  295  66 34   6.6   3.6 | -24.5 -12.1  300  68 35   6.0   3.3
 26000 -24.6 -12.3  285  58 30   6.6   3.6 | -22.7  -8.9  295  62 32   6.0   3.3
 25000 -22.7  -8.9  280  52 27   6.5   3.6 | -20.9  -5.6  295  56 29   5.9   3.2
 24000 -20.5  -4.9  280  50 26   7.7   4.2 | -19.0  -2.2  290  53 27   6.7   3.7
 23000 -18.1  -0.6  275  49 25   7.7   4.2 | -17.0   1.4  290  51 26   6.8   3.7
 22000 -15.8   3.6  275  48 25   7.8   4.3 | -15.0   5.0  285  50 26   6.9   3.8
 21000 -13.7   7.3  275  47 24   7.1   3.9 | -13.0   8.6  285  49 25   7.0   3.8
 20000 -11.6  11.1  270  47 24   7.2   3.9 | -10.8  12.6  280  48 25   7.0   3.8
 19500 -10.5  13.1  270  47 24   7.2   3.9 |  -9.8  14.4  280  47 24   7.0   3.8
 19000  -9.5  14.9  270  47 24   7.0   3.8 |  -8.7  16.3  280  47 24   6.3   3.4
 18500  -8.5  16.7  270  47 24   6.9   3.8 |  -7.9  17.8  280  47 24   6.0   3.3
 18000  -7.5  18.5  270  47 24   6.9   3.8 |  -7.0  19.4  275  47 24   6.1   3.3
 17500  -6.4  20.5  270  47 24   7.9   4.4 |  -6.1  21.0  275  46 24   7.2   3.9
 17000  -5.2  22.6  275  46 24   7.9   4.3 |  -5.0  23.0  275  45 23   7.1   3.9
 16500  -4.0  24.8  275  45 23   7.5   4.1 |  -4.0  24.8  275  44 22   7.8   4.3
 16000  -2.9  26.8  275  44 22   7.4   4.0 |  -2.8  27.0  275  42 21   8.1   4.4
 15500  -1.8  28.8  275  42 22   7.3   4.0 |  -1.6  29.1  275  39 20   8.1   4.5
 15000  -0.8  30.6  270  40 21   7.2   3.9 |  -0.4  31.3  270  37 19   8.2   4.5
 14500   0.2  32.4  270  38 20   7.3   4.0 |   0.8  33.4  270  36 18   8.2   4.5
 14000   1.3  34.3  270  36 19   8.2   4.5 |   2.0  35.6  270  34 18   8.7   4.8
 13500   2.4  36.3  270  35 18   8.1   4.4 |   3.3  37.9  270  33 17   8.7   4.8
 13000   4.3  39.7  270  33 17   9.2   5.1 |   5.2  41.4  270  31 16   9.0   4.9
 12500   5.7  42.3  265  32 16   9.2   5.0 |   6.5  43.7  270  30 16   9.0   4.9
 12000   7.0  44.6  265  30 16   9.0   4.9 |   7.8  46.0  270  29 15   9.0   4.9
 11500   8.4  47.1  265  29 15   9.0   4.9 |   9.1  48.4  270  29 15   9.0   5.0
 11000   9.6  49.3  265  28 14   7.7   4.2 |  10.4  50.7  270  28 14   8.4   4.6
 10500  10.7  51.3  265  26 13  10.5   5.8 |  11.6  52.9  270  27 14  10.9   6.0
 10250  11.6  52.9  260  25 13  10.9   6.0 |  12.6  54.7  270  27 14  11.2   6.1
 10000  12.2  54.0  260  23 12   7.5   4.1 |  13.2  55.8  270  26 14   7.9   4.3
  9750  12.8  55.0  260  21 11   8.4   4.6 |  13.8  56.8  270  26 13   8.9   4.9
  9500  13.4  56.1  260  20 10   8.4   4.6 |  14.5  58.1  270  26 13   8.2   4.5
  9250  14.1  57.4  260  19 10   9.2   5.1 |  15.0  59.0  270  25 13   8.0   4.4
  9000  14.7  58.5  260  18  9   9.6   5.3 |  15.7  60.3  270  24 13   8.5   4.6
  8750  15.4  59.7  260  17  9   9.4   5.1 |  16.3  61.3  270  23 12   8.6   4.7
  8500  16.1  61.0  265  17  9   9.7   5.3 |  16.9  62.4  270  22 11   8.6   4.7
  8250  16.9  62.4  265  16  8  10.3   5.7 |  17.5  63.5  270  21 11   8.7   4.8
  8000  17.6  63.7  265  16  8   9.8   5.4 |  18.2  64.8  270  19 10   8.3   4.6
  7750  18.3  64.9  265  16  8   9.1   5.0 |  18.8  65.8  270  17  9   7.8   4.3
  7500  19.0  66.2  265  16  8   9.8   5.4 |  19.3  66.7  270  16  8   8.6   4.7
  7250  19.8  67.6  265  15  8  10.6   5.8 |  20.0  68.0  270  15  8  10.0   5.5
  7000  20.6  69.1  265  15  8  10.3   5.7 |  20.8  69.4  270  15  7   9.8   5.4
  6750  21.3  70.3  265  15  8   9.8   5.4 |  21.5  70.7  270  14  7   8.9   4.9
  6500  22.1  71.8  265  15  8  10.6   5.8 |  22.2  72.0  275  14  7   9.9   5.4
  6250  22.9  73.2  265  14  7  11.6   6.4 |  22.9  73.2  275  13  7  10.8   5.9
  6000  23.7  74.7  265  14  7  10.5   5.8 |  23.7  74.7  275  13  7  10.6   5.8
  5750  24.5  76.1  265  13  7  10.7   5.9 |  24.5  76.1  275  12  6   9.8   5.4
  5500  25.4  77.7  265  13  7  13.6   7.4 |  25.1  77.2  275  11  6   8.2   4.5
  5250  26.5  79.7  265  13  7  15.4   8.5 |  25.7  78.3  275  11  6   7.4   4.0
  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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NOAA National Weather Service
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Silver Spring, MD 20910
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Page last modified: May 16, 2007
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