Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221236
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0636 MDT Wednesday, October 22, 2014

This forecast is for Wednesday, October 22, 2014:

If the trigger temperature of 67.1 F/19.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 520 ft/min (2.6 m/s)
   Maximum height of thermals.................. 9427 ft MSL (4588 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1430 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7218 ft MSL (2379 ft AGL)
Thermal soaring outlook for Thursday 10/23..... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:31:06 / 18:27:01 MDT
Total possible sunshine........... 10 hr 55 min 55 sec (655 min 55 sec)
Altitude of sun at 12:58:39 MDT... 39.68 degrees

Upper air data from rawinsonde observation taken on 10/22/2014 at 0600 MDT

Freezing level.................. 11891 ft MSL (7052 ft AGL)
Convective condensation level... 11980 ft MSL (7141 ft AGL)
Lifted condensation level....... 11571 ft MSL (6731 ft AGL)
Lifted index.................... +0.1
K index......................... +25.4

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -61.8 -79.2   260   36   18   1.5   0.8   96.7 206.1    43.8      M    M
 45000  -55.2 -67.4   250   31   16   3.7   2.0   81.9 179.4    38.0      M    M
 40000  -57.1 -70.8   280   31   16   7.2   4.0   56.0 132.8    23.7      M    M
 38000  -54.8 -66.6   295   38   19   3.4   1.9   50.5 122.9    20.6      M    M
 36000  -53.9 -65.0   305   49   25   5.3   2.9   43.4 110.2    16.2      M    M
 34000  -50.6 -59.1   310   61   31   6.4   3.5   39.8 103.6    14.1      M    M
 32000  -45.3 -49.5   310   61   32   7.7   4.2   38.0 100.3    13.2      M    M
 30000  -40.4 -40.7   295   49   25   7.9   4.3   36.7  98.0    12.5      M    M
 29000  -38.0 -36.4   290   44   23   8.2   4.5   35.9  96.7    12.1      M    M
 28000  -35.4 -31.7   290   40   21   8.9   4.9   35.5  95.9    11.9      M    M
 27000  -32.7 -26.9   285   36   19   9.3   5.1   35.3  95.5    11.9      M    M
 26000  -30.0 -22.0   280   37   19   8.8   4.8   35.0  94.9    11.8      M    M
 25000  -27.5 -17.5   275   39   20   6.4   3.5   34.5  94.1    11.5      M    M
 24000  -25.2 -13.4   275   39   20   8.4   4.6   33.7  92.7    11.0      M    M
 23000  -23.2  -9.8   270   37   19   6.2   3.4   32.6  90.8    10.3      M    M
 22000  -21.8  -7.2   260   36   19   7.1   3.9   30.9  87.6     8.9      M    M
 21000  -19.1  -2.4   255   36   19   7.9   4.3   30.6  87.1     8.7      M    M
 20000  -17.5   0.5   260   34   18   4.9   2.7   29.2  84.6     7.6      M    M
 19500  -16.7   1.9   260   33   17   6.2   3.4   28.5  83.3     6.9      M    M
 19000  -15.7   3.7   265   32   16   7.1   3.9   27.9  82.3     6.5      M    M
 18500  -14.7   5.5   265   30   16   5.3   2.9   27.3  81.1     6.1      M    M
 18000  -13.9   7.0   270   29   15   5.7   3.1   26.6  79.9     5.5      M    M
 17500  -12.5   9.5   265   27   14   7.4   4.1   25.7  78.2     4.7      M    M
 17000  -11.6  11.1   265   26   13   5.0   2.7   24.9  76.7     4.2      M    M
 16500  -10.4  13.3   260   25   13   7.7   4.2   24.5  76.1     3.9      M    M
 16000   -9.3  15.3   260   24   12   6.8   3.7   24.1  75.4     3.6      M    M
 15500   -8.7  16.3   255   25   13   3.1   1.7   23.4  74.1     2.8      M    M
 15000   -8.0  17.6   255   27   14   8.2   4.5   22.8  73.0     2.0      M    M
 14500   -7.1  19.2   250   28   14   5.9   3.2   22.2  72.0     1.5      M    M
 14000   -6.0  21.2   250   29   15  10.1   5.6   21.9  71.4     1.1      M    M
 13500   -4.5  23.9   250   27   14   9.8   5.4   21.9  71.4     1.1      M    M
 13000   -3.1  26.4   250   25   13   9.8   5.4   21.9  71.4     1.1      M    M
 12500   -1.6  29.1   245   24   12   9.9   5.4   21.9  71.4     1.1      M    M
 12000   -0.2  31.6   245   22   11   8.6   4.7   21.9  71.4     1.1      M    M
 11500    1.0  33.8   245   20   10   8.3   4.6   21.6  70.9     0.8      M    M
 11000    2.3  36.1   250   19   10   8.3   4.6   21.4  70.5     0.6      M    M
 10500    3.5  38.3   255   17    9   8.2   4.5   21.2  70.1     0.4      M    M
 10250    4.1  39.4   255   16    8   8.7   4.8   21.1  69.9     0.3      M    M
 10000    4.8  40.6   255   16    8   9.5   5.2   21.0  69.9     0.2      M    M
  9750    5.5  41.9   255   16    8   8.9   4.9   21.0  69.8     0.2      M    M
  9500    6.1  43.0   250   16    8   7.6   4.2   20.9  69.6     0.1      M    M
  9250    6.6  43.9   250   16    8   7.2   3.9   20.7  69.3    -0.1    305  1.5
  9000    7.1  44.8   250   16    8   7.3   4.0   20.5  68.9    -0.3    282  1.4
  8750    7.6  45.7   245   15    7   7.3   4.0   20.3  68.6    -0.6    259  1.3
  8500    8.2  46.8   245   13    7   7.3   4.0   20.1  68.2    -0.8    236  1.2
  8250    8.7  47.7   240   12    6   7.4   4.0   19.9  67.9    -1.0    213  1.1
  8000    9.2  48.6   230   10    5   7.0   3.8   19.7  67.5    -1.2    190  1.0
  7750    9.7  49.5   215    9    5   8.4   4.6   19.5  67.2    -1.4    167  0.9
  7500   10.2  50.4   200    8    4   3.3   1.8   19.4  66.8    -1.6    145  0.7
  7250   10.0  50.0   180    9    4  -5.8  -3.2   18.4  65.2    -2.6    143  0.7
  7000    9.4  48.9   165   10    5  -6.9  -3.8   17.2  62.9    -3.9    153  0.8
  6750    9.1  48.4   150    9    5   1.0   0.5   16.1  61.0    -5.0    156  0.8
  6500    9.5  49.1   140    9    4   5.8   3.2   15.7  60.3    -5.3    136  0.7
  6250    9.9  49.8   125    9    4   3.3   1.8   15.3  59.6    -5.7    118  0.6
  6000   10.1  50.2   115    9    5   3.0   1.6   14.8  58.7    -6.2    105  0.5
  5750   10.3  50.5   110    7    4   3.0   1.6   14.3  57.8    -6.8     92  0.5
  5500   10.5  50.9   110    5    3   3.3   1.8   13.8  56.8    -7.3     78  0.4
  5250   10.7  51.3   110    3    2   2.0   1.1   13.3  55.9    -7.9     65  0.3
  5000   10.5  50.9   110    1    1  -7.0  -3.8   12.4  54.4    -8.7     62  0.3

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

           10/22/2014 at 0900 MDT          |       10/22/2014 at 1200 MDT
                                           |
K index... +20.5  LI... -0.9               | K index... +12.7  LI... +0.2
CAPE... +68.1  CIN... -33.9                | CAPE... +20.0  CIN... -71.1
                                           |
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 -61.8 -79.2  285  26 14   3.6   2.0 | -62.1 -79.8  290  35 18   3.5   1.9
 45000 -56.8 -70.2  295  33 17   0.2   0.1 | -57.5 -71.5  305  45 23   0.3   0.2
 40000 -56.6 -69.9  300  38 20   0.1   0.1 | -57.1 -70.8  320  59 31   0.1   0.0
 38000 -54.8 -66.6  305  43 22   3.7   2.0 | -54.9 -66.8  320  59 30   4.4   2.4
 36000 -52.6 -62.7  310  50 26   3.7   2.0 | -52.2 -62.0  315  57 29   4.5   2.4
 34000 -49.3 -56.7  310  53 27   8.3   4.6 | -48.0 -54.4  315  56 29   7.9   4.4
 32000 -43.6 -46.5  310  53 27   8.3   4.6 | -43.2 -45.8  310  56 29   7.9   4.4
 30000 -38.7 -37.7  305  49 25   8.3   4.5 | -38.2 -36.8  310  54 28   8.6   4.7
 29000 -36.2 -33.2  305  46 24   8.3   4.5 | -35.6 -32.1  315  52 27   8.6   4.7
 28000 -33.7 -28.7  300  43 22   8.2   4.5 | -33.1 -27.6  315  51 26   8.6   4.7
 27000 -31.3 -24.3  295  41 21   7.8   4.3 | -30.5 -22.9  310  48 25   8.4   4.6
 26000 -29.0 -20.2  290  39 20   7.8   4.3 | -28.0 -18.4  305  45 23   8.4   4.6
 25000 -26.7 -16.1  290  37 19   7.8   4.3 | -25.5 -13.9  300  42 22   8.4   4.6
 24000 -24.5 -12.1  285  36 19   6.3   3.4 | -23.2  -9.8  295  40 20   6.6   3.6
 23000 -22.6  -8.7  280  35 18   6.4   3.5 | -21.2  -6.2  290  38 19   6.7   3.7
 22000 -20.7  -5.3  280  34 17   6.4   3.5 | -19.2  -2.6  290  36 19   6.7   3.7
 21000 -18.9  -2.0  275  33 17   5.7   3.1 | -17.5   0.5  285  34 18   5.1   2.8
 20000 -17.2   1.0  270  31 16   5.7   3.1 | -16.0   3.2  280  32 16   5.1   2.8
 19500 -16.4   2.5  270  30 16   5.7   3.1 | -15.2   4.6  280  30 16   5.2   2.8
 19000 -15.6   3.9  270  30 15   5.7   3.1 | -14.5   5.9  280  29 15   5.2   2.8
 18500 -14.7   5.5  265  29 15   5.4   3.0 | -13.7   7.3  275  28 15   5.2   2.9
 18000 -13.9   7.0  265  28 14   5.4   3.0 | -13.0   8.6  270  28 14   5.2   2.9
 17500 -13.1   8.4  265  27 14   6.6   3.6 | -12.2  10.0  270  27 14   5.4   3.0
 17000 -12.0  10.4  265  26 13   7.1   3.9 | -11.3  11.7  265  27 14   5.6   3.0
 16500 -10.9  12.4  265  25 13   7.3   4.0 | -10.5  13.1  265  26 13   6.1   3.4
 16000  -9.7  14.5  265  24 12   7.9   4.3 |  -9.3  15.3  260  25 13   8.0   4.4
 15500  -8.6  16.5  265  23 12   7.9   4.4 |  -7.5  18.5  260  23 12   7.4   4.1
 15000  -7.0  19.4  265  22 11   7.4   4.0 |  -6.4  20.5  260  21 11   7.0   3.8
 14500  -6.0  21.2  265  21 11   7.6   4.2 |  -5.4  22.3  260  20 10   6.9   3.8
 14000  -4.8  23.4  265  20 11   8.1   4.5 |  -4.4  24.1  260  18  9   6.9   3.8
 13500  -3.7  25.3  265  20 10   8.2   4.5 |  -3.5  25.7  260  17  9   7.1   3.9
 13000  -2.5  27.5  265  19 10   8.5   4.7 |  -2.4  27.7  260  16  8   8.0   4.4
 12500  -1.2  29.8  265  19 10   8.5   4.7 |  -1.3  29.7  260  16  8   8.0   4.4
 12000   0.0  32.0  265  18  9   8.4   4.6 |  -0.1  31.8  255  15  8   8.7   4.8
 11500   1.3  34.3  260  17  9   8.4   4.6 |   1.1  34.0  255  15  8   8.7   4.7
 11000   2.5  36.5  260  17  9   8.2   4.5 |   2.4  36.3  255  15  8   8.2   4.5
 10500   3.6  38.5  260  16  8   7.5   4.1 |   3.6  38.5  255  15  8   7.0   3.8
 10250   4.1  39.4  260  16  8   4.6   2.5 |   4.0  39.2  250  15  7   4.8   2.7
 10000   4.4  39.9  260  15  8   7.0   3.8 |   4.4  39.9  250  14  7   7.5   4.1
  9750   5.1  41.2  255  15  8   9.9   5.4 |   5.0  41.0  250  13  7   9.6   5.2
  9500   5.7  42.3  255  14  7   8.5   4.7 |   5.7  42.3  250  13  7   8.4   4.6
  9250   6.2  43.2  255  13  7   5.5   3.0 |   6.2  43.2  250  12  6   6.3   3.4
  9000   6.6  43.9  255  12  6   4.6   2.5 |   6.6  43.9  250  11  6   6.1   3.4
  8750   7.0  44.6  250  11  6   5.7   3.2 |   7.1  44.8  250  10  5   7.3   4.0
  8500   7.4  45.3  250   9  5   5.1   2.8 |   7.6  45.7  245   9  5   6.2   3.4
  8250   7.7  45.9  245   8  4   4.4   2.4 |   8.0  46.4  245   8  4   4.9   2.7
  8000   8.0  46.4  245   7  3   4.6   2.5 |   8.3  46.9  245   7  3   4.9   2.7
  7750   8.4  47.1  240   6  3   5.2   2.9 |   8.7  47.7  240   5  3   5.2   2.8
  7500   8.8  47.8  235   5  3   4.9   2.7 |   9.1  48.4  240   4  2   5.6   3.1
  7250   9.1  48.4  230   5  3   4.4   2.4 |   9.5  49.1  240   4  2   5.8   3.2
  7000   9.4  48.9  220   5  3   4.9   2.7 |   9.9  49.8  240   3  2   6.1   3.3
  6750   9.8  49.6  210   5  3   3.6   2.0 |  10.4  50.7  240   3  1   8.4   4.6
  6500   9.9  49.8  200   5  3   0.9   0.5 |  11.1  52.0  245   2  1  10.5   5.8
  6250   9.9  49.8  190   4  2  -0.7  -0.4 |  11.9  53.4  245   3  1  11.0   6.1
  6000   9.9  49.8  175   3  2   2.0   1.1 |  12.7  54.9  245   3  1   9.9   5.4
  5750  10.1  50.2  130   3  1   0.4   0.2 |  13.4  56.1  250   3  1  10.7   5.9
  5500   9.9  49.8  115   2  1  -4.0  -2.2 |  14.3  57.7  250   3  1  12.7   7.0
  5250   9.7  49.5  100   2  1  -0.5  -0.3 |  15.2  59.4  250   3  1  11.1   6.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           10/22/2014 at 1500 MDT          |       10/22/2014 at 1800 MDT
                                           |
K index... +17.4  LI... +0.8               | K index... +15.1  LI... +2.3
CAPE... +20.0  CIN... -41.5                | CAPE... 0.0  CIN... -7.6
                                           |
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 -63.4 -82.1  290  36 19   2.5   1.4 | -64.0 -83.2  290  43 22   2.4   1.3
 45000 -60.1 -76.2  305  51 26   0.5   0.3 | -60.8 -77.4  300  58 30   0.9   0.5
 40000 -59.3 -74.7  320  70 36   1.8   1.0 | -59.4 -74.9  320  65 34   3.2   1.8
 38000 -55.3 -67.5  320  65 33   7.0   3.8 | -55.1 -67.2  320  62 32   7.4   4.1
 36000 -51.1 -60.0  315  59 30   7.0   3.8 | -50.6 -59.1  315  58 30   7.4   4.1
 34000 -46.8 -52.2  315  55 28   7.5   4.1 | -46.1 -51.0  315  55 28   7.7   4.2
 32000 -42.3 -44.1  315  53 28   7.5   4.1 | -41.4 -42.5  315  52 27   7.7   4.2
 30000 -37.6 -35.7  315  51 26   8.4   4.6 | -36.7 -34.1  310  47 24   8.1   4.5
 29000 -35.1 -31.2  315  49 25   8.4   4.6 | -34.2 -29.6  310  43 22   8.1   4.5
 28000 -32.6 -26.7  315  47 24   8.4   4.6 | -31.8 -25.2  310  40 20   8.2   4.5
 27000 -30.1 -22.2  310  44 23   8.4   4.6 | -28.7 -19.7  305  37 19   8.5   4.7
 26000 -27.0 -16.6  305  39 20   8.4   4.6 | -26.1 -15.0  300  36 18   8.6   4.7
 25000 -24.5 -12.1  300  35 18   8.4   4.6 | -23.6 -10.5  295  34 18   8.5   4.7
 24000 -22.0  -7.6  295  33 17   7.8   4.3 | -21.3  -6.3  295  33 17   7.1   3.9
 23000 -19.7  -3.5  295  33 17   7.8   4.3 | -19.2  -2.6  290  32 16   7.1   3.9
 22000 -17.4   0.7  295  32 17   7.8   4.3 | -17.1   1.2  290  31 16   7.2   3.9
 21000 -15.7   3.7  290  31 16   4.9   2.7 | -15.4   4.3  290  29 15   4.9   2.7
 20000 -14.2   6.4  290  29 15   4.9   2.7 | -13.9   7.0  290  27 14   4.9   2.7
 19500 -13.5   7.7  285  28 15   4.9   2.7 | -13.2   8.2  285  26 14   4.9   2.7
 19000 -12.8   9.0  285  28 14   4.7   2.6 | -12.5   9.5  285  25 13   4.7   2.6
 18500 -12.2  10.0  280  27 14   4.0   2.2 | -11.9  10.6  285  25 13   4.4   2.4
 18000 -11.7  10.9  280  26 14   4.1   2.2 | -11.2  11.8  285  24 12   4.5   2.4
 17500 -11.1  12.0  275  26 13   4.4   2.4 | -10.6  12.9  280  23 12   4.3   2.3
 17000 -10.4  13.3  270  26 13   4.5   2.5 | -10.0  14.0  280  23 12   4.3   2.4
 16500  -9.8  14.4  265  25 13   5.7   3.1 |  -9.4  15.1  275  23 12   4.9   2.7
 16000  -8.7  16.3  265  25 13   7.3   4.0 |  -8.6  16.5  270  22 12   5.7   3.1
 15500  -7.6  18.3  260  25 13   7.4   4.0 |  -7.7  18.1  270  22 12   6.0   3.3
 15000  -6.5  20.3  260  24 12   7.1   3.9 |  -6.6  20.1  265  22 11   8.8   4.8
 14500  -5.4  22.3  260  22 11   7.1   3.9 |  -5.3  22.5  260  21 11   8.6   4.7
 14000  -4.3  24.3  260  21 11   7.6   4.2 |  -4.0  24.8  260  21 11   8.8   4.8
 13500  -3.2  26.2  255  20 10   7.6   4.2 |  -2.6  27.3  255  20 10   8.9   4.9
 13000  -1.5  29.3  255  18  9   7.7   4.2 |  -0.7  30.7  250  19 10   8.2   4.5
 12500  -0.4  31.3  255  17  9   7.7   4.2 |   0.4  32.7  250  19 10   8.2   4.5
 12000   0.7  33.3  255  17  9   7.8   4.3 |   1.6  34.9  250  18  9   8.2   4.5
 11500   1.8  35.2  255  16  8   7.9   4.3 |   2.8  37.0  250  17  9   8.2   4.5
 11000   2.9  37.2  255  15  8   8.3   4.6 |   4.0  39.2  255  16  8   7.7   4.2
 10500   4.1  39.4  250  15  7   5.5   3.0 |   5.2  41.4  255  14  7   5.0   2.7
 10250   4.4  39.9  255  14  7   5.4   3.0 |   5.4  41.7  255  14  7   4.5   2.5
 10000   5.0  41.0  255  14  7  10.1   5.6 |   5.9  42.6  260  13  7   8.8   4.8
  9750   5.7  42.3  255  13  7  10.2   5.6 |   6.6  43.9  260  12  6   8.8   4.8
  9500   6.4  43.5  255  12  6   9.1   5.0 |   7.2  45.0  260  12  6   8.0   4.4
  9250   7.0  44.6  255  11  6   6.5   3.5 |   7.7  45.9  265  11  6   6.2   3.4
  9000   7.5  45.5  260  11  5   6.8   3.8 |   8.1  46.6  265  11  5   6.6   3.6
  8750   8.0  46.4  260  10  5   8.3   4.6 |   8.6  47.5  270  10  5   7.5   4.1
  8500   8.6  47.5  265   9  4   6.7   3.7 |   9.2  48.6  275   9  5   6.7   3.7
  8250   8.9  48.0  270   7  4   4.5   2.5 |   9.6  49.3  275   8  4   6.0   3.3
  8000   9.3  48.7  270   6  3   5.5   3.0 |  10.0  50.0  280   8  4   6.1   3.3
  7750   9.7  49.5  280   5  3   6.5   3.6 |  10.5  50.9  285   6  3   6.1   3.3
  7500  10.2  50.4  285   4  2   8.4   4.6 |  10.9  51.6  295   5  3   6.4   3.5
  7250  10.9  51.6  285   4  2  10.2   5.6 |  11.4  52.5  300   4  2   6.5   3.5
  7000  11.6  52.9  285   4  2   9.6   5.3 |  11.8  53.2  305   3  2   7.1   3.9
  6750  12.3  54.1  285   4  2  10.1   5.6 |  12.3  54.1  310   2  1   8.9   4.9
  6500  13.1  55.6  285   4  2  10.8   5.9 |  13.0  55.4  310   2  1   9.8   5.4
  6250  13.9  57.0  285   4  2  11.4   6.3 |  13.7  56.7  305   2  1   9.8   5.4
  6000  14.7  58.5  285   4  2   9.7   5.3 |  14.4  57.9  300   2  1   9.8   5.4
  5750  15.4  59.7  280   4  2  10.3   5.6 |  15.1  59.2  300   2  1   6.3   3.5
  5500  16.3  61.3  285   4  2  12.8   7.0 |  15.4  59.7  300   2  1   3.1   1.7
  5250  17.2  63.0  285   4  2  10.7   5.9 |  15.6  60.1  305   2  1   5.5   3.0
  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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