Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 211228
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0628 MDT Sunday, September 21, 2014

This forecast is for Sunday, September 21, 2014:

If the trigger temperature of 79.2 F/26.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 404 ft/min (2.1 m/s)
   Maximum height of thermals.................. 10263 ft MSL (5424 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ 1345 MDT
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................. 5467 ft MSL (628 ft AGL)
Thermal soaring outlook for Monday 09/22....... Good

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

Remarks...

Sunrise/Sunset.................... 07:00:56 / 19:14:14 MDT
Total possible sunshine........... 12 hr 13 min 19 sec (733 min 19 sec)
Altitude of sun at 13:07:05 MDT... 51.40 degrees

Upper air data from rawinsonde observation taken on 09/21/2014 at 0600 MDT

Freezing level.................. 15206 ft MSL (10367 ft AGL)
Convective condensation level... 14964 ft MSL (10125 ft AGL)
Lifted condensation level....... 13575 ft MSL (8736 ft AGL)
Lifted index.................... +0.2
K index......................... +31.4

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  -69.6 -93.3   265   34   18   7.6   4.2   79.0 174.1    29.9      M    M
 45000  -60.9 -77.6   255   59   30   5.3   2.9   67.6 153.8    25.2      M    M
 40000  -52.0 -61.6   250   60   31   6.9   3.8   59.1 138.3    21.2      M    M
 38000  -48.8 -55.8   250   50   26   5.2   2.9   55.0 130.9    19.0      M    M
 36000  -45.2 -49.4   245   39   20   5.9   3.2   51.9 125.4    17.3      M    M
 34000  -40.5 -40.9   235   37   19   8.4   4.6   50.2 122.4    16.5      M    M
 32000  -35.8 -32.4   225   36   19  11.8   6.5   47.7 117.9    15.1      M    M
 30000  -30.5 -22.9   220   25   13   8.7   4.8   47.0 116.6    14.9      M    M
 29000  -28.1 -18.6   215   21   11   7.3   4.0   46.4 115.5    14.6      M    M
 28000  -25.9 -14.6   210   21   11   7.4   4.1   45.5 113.9    14.1      M    M
 27000  -23.6 -10.5   210   21   11   7.7   4.2   44.7 112.4    13.6      M    M
 26000  -21.4  -6.5   205   22   11   7.7   4.2   43.8 110.9    13.0      M    M
 25000  -19.1  -2.4   205   22   11   6.2   3.4   43.1 109.6    12.5      M    M
 24000  -17.5   0.5   205   20   10   5.4   3.0   41.4 106.5    11.3      M    M
 23000  -15.9   3.4   200   18    9  -4.3  -2.4   39.9 103.7    10.1      M    M
 22000  -13.7   7.3   235   14    7  10.0   5.5   39.2 102.5     9.5      M    M
 21000  -12.1  10.2   225   14    7   0.1   0.1   37.7  99.9     8.3      M    M
 20000  -10.6  12.9   210   15    8   2.3   1.2   36.0  96.9     7.0      M    M
 19500   -9.8  14.4   215   14    7   6.6   3.6   35.2  95.4     6.3      M    M
 19000   -8.3  17.1   210   13    6  13.4   7.4   35.4  95.8     6.4      M    M
 18500   -7.0  19.4   205   12    6   8.9   4.9   35.3  95.6     6.3      M    M
 18000   -5.7  21.7   200   11    6  11.5   6.3   35.1  95.3     6.1      M    M
 17500   -5.5  22.1   190   11    6   2.4   1.3   33.7  92.6     5.0      M    M
 17000   -3.2  26.2   180   11    6   2.3   1.3   34.0  93.2     5.1      M    M
 16500   -2.7  27.1   185   13    7   8.7   4.8   32.9  91.2     4.2      M    M
 16000   -1.3  29.7   185   15    8   5.6   3.1   32.9  91.3     4.1      M    M
 15500   -0.4  31.3   195   15    8   6.6   3.6   32.3  90.2     3.6      M    M
 15000    0.7  33.3   200   15    8   7.8   4.3   32.0  89.6     3.2      M    M
 14500    1.8  35.2   205   16    8   7.8   4.3   31.7  89.0     3.0      M    M
 14000    3.0  37.4   210   16    8   7.8   4.3   31.4  88.5     2.7      M    M
 13500    4.1  39.4   220   14    7   7.8   4.3   31.1  88.0     2.4      M    M
 13000    5.3  41.5   225   13    7   7.8   4.3   30.8  87.5     2.2      M    M
 12500    6.4  43.5   225   12    6   7.8   4.3   30.5  86.9     1.9      M    M
 12000    7.6  45.7   225   12    6   7.8   4.3   30.2  86.3     1.6      M    M
 11500    8.7  47.7   220   10    5   7.8   4.3   29.8  85.7     1.2      M    M
 11000    9.9  49.8   215    9    5   7.6   4.2   29.5  85.2     0.9      M    M
 10500   11.0  51.8   195   10    5   4.5   2.5   29.2  84.6     0.6      M    M
 10250   11.1  52.0   185   13    7  -0.5  -0.3   28.5  83.3    -0.0    403  2.0
 10000   11.2  52.2   175   18    9   4.5   2.5   27.8  82.1    -0.7    393  2.0
  9750   11.8  53.2   175   20   10   9.1   5.0   27.7  81.8    -0.8    369  1.9
  9500   12.4  54.3   180   21   11   9.1   5.0   27.6  81.7    -0.9    341  1.7
  9250   13.1  55.6   180   23   12   9.1   5.0   27.6  81.7    -0.9    313  1.6
  9000   13.8  56.8   180   25   13   9.1   5.0   27.6  81.6    -0.9    285  1.4
  8750   14.5  58.1   175   25   13   9.1   5.0   27.5  81.5    -1.0    258  1.3
  8500   15.2  59.4   170   24   12   9.1   5.0   27.5  81.5    -1.0    230  1.2
  8250   15.8  60.4   165   24   12   9.1   5.0   27.4  81.4    -1.1    202  1.0
  8000   16.5  61.7   160   24   12   9.1   5.0   27.4  81.3    -1.1    174  0.9
  7750   17.2  63.0   160   25   13   9.1   5.0   27.3  81.2    -1.2    147  0.7
  7500   17.9  64.2   155   27   14   9.1   5.0   27.3  81.1    -1.2    119  0.6
  7250   18.5  65.3   155   29   15   9.1   5.0   27.2  81.0    -1.3     91  0.5
  7000   19.2  66.6   155   31   16   9.1   5.0   27.2  80.9    -1.3     63  0.3
  6750   19.9  67.8   155   31   16   9.2   5.0   27.1  80.8    -1.4     35  0.2
  6500   20.6  69.1   155   30   16   8.9   4.9   27.1  80.7    -1.4      8  0.0
  6250   21.3  70.3   155   30   15   9.7   5.3   27.0  80.6    -1.5      M    M
  6000   21.9  71.4   155   29   15   6.8   3.8   27.0  80.5    -1.6      M    M
  5750   22.2  72.0   155   26   13   1.5   0.8   26.5  79.7    -2.0      M    M
  5500   22.3  72.1   150   22   11   0.3   0.1   25.8  78.4    -2.7      M    M
  5250   22.3  72.1   145   18    9   1.1   0.6   25.1  77.2    -3.4      M    M
  5000   22.4  72.3   135   14    7  -1.1  -0.6   24.4  76.0    -4.1      M    M

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

           09/21/2014 at 0900 MDT          |       09/21/2014 at 1200 MDT
                                           |
K index... +28.3  LI... -1.7               | K index... +24.9  LI... -1.7
CAPE... +111.5  CIN... -159.2              | CAPE... +107.2  CIN... -58.5
                                           |
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 -66.4 -87.5  275  31 16   3.1   1.7 | -66.7 -88.1  270  31 16   2.8   1.5
 45000 -60.1 -76.2  265  50 26   6.0   3.3 | -60.8 -77.4  265  47 24   6.0   3.3
 40000 -51.2 -60.2  260  59 30   5.5   3.0 | -51.7 -61.1  255  58 30   6.1   3.3
 38000 -47.9 -54.2  260  50 26   5.5   3.0 | -48.1 -54.6  255  48 25   6.1   3.3
 36000 -44.6 -48.3  260  40 21   5.3   2.9 | -44.4 -47.9  255  38 20   5.9   3.2
 34000 -39.8 -39.6  255  29 15   7.4   4.1 | -39.3 -38.7  245  30 15   7.8   4.3
 32000 -35.3 -31.5  240  21 11   7.9   4.3 | -34.6 -30.3  235  24 12   8.3   4.6
 30000 -30.3 -22.5  215  18  9   8.6   4.7 | -29.7 -21.5  225  22 11   8.4   4.6
 29000 -27.7 -17.9  205  19 10   8.6   4.7 | -27.2 -17.0  220  21 11   8.4   4.6
 28000 -25.2 -13.4  195  20 10   7.3   4.0 | -24.7 -12.5  220  20 10   7.0   3.8
 27000 -23.1  -9.6  200  21 11   7.1   3.9 | -22.7  -8.9  215  22 11   6.9   3.8
 26000 -21.0  -5.8  200  22 11   7.1   3.9 | -20.7  -5.3  215  23 12   6.9   3.8
 25000 -18.9  -2.0  205  23 12   7.0   3.8 | -18.7  -1.7  210  24 12   6.9   3.8
 24000 -17.1   1.2  205  22 11   6.1   3.3 | -16.7   1.9  210  24 12   6.9   3.8
 23000 -15.4   4.3  205  21 11   6.1   3.3 | -14.7   5.5  215  23 12   6.9   3.8
 22000 -13.6   7.5  210  19 10   6.1   3.4 | -12.6   9.3  215  22 11   6.5   3.6
 21000 -11.7  10.9  210  20 10   6.3   3.5 | -11.0  12.2  215  22 11   5.3   2.9
 20000  -9.9  14.2  210  21 11   6.3   3.5 |  -9.4  15.1  215  22 12   5.3   2.9
 19500  -8.5  16.7  210  22 11   6.4   3.5 |  -8.2  17.2  215  23 12   5.8   3.2
 19000  -7.5  18.5  215  23 12   6.5   3.6 |  -7.3  18.9  215  23 12   6.5   3.6
 18500  -6.6  20.1  215  24 12   6.5   3.6 |  -6.3  20.7  215  23 12   6.6   3.6
 18000  -5.6  21.9  215  25 13   6.8   3.7 |  -5.4  22.3  210  24 12   6.1   3.4
 17500  -4.6  23.7  220  25 13   6.8   3.7 |  -4.5  23.9  210  23 12   6.1   3.4
 17000  -3.6  25.5  220  26 13   6.7   3.7 |  -3.6  25.5  210  23 12   6.2   3.4
 16500  -2.7  27.1  220  25 13   6.5   3.5 |  -2.7  27.1  210  22 11   6.2   3.4
 16000  -1.8  28.8  220  25 13   6.5   3.6 |  -1.8  28.8  205  21 11   6.2   3.4
 15500  -0.9  30.4  220  24 12   6.6   3.6 |  -0.9  30.4  205  20 10   7.1   3.9
 15000   0.1  32.2  220  22 12   6.5   3.6 |   0.1  32.2  205  18  9   7.0   3.8
 14500   1.0  33.8  215  21 11   7.4   4.0 |   1.2  34.2  205  16  8   7.8   4.3
 14000   2.1  35.8  215  20 10   7.5   4.1 |   2.3  36.1  205  16  8   7.9   4.3
 13500   3.2  37.8  210  18  9   7.7   4.2 |   3.5  38.3  205  15  8   7.9   4.3
 13000   4.3  39.7  205  17  9   7.8   4.3 |   4.6  40.3  200  16  8   7.8   4.3
 12500   5.4  41.7  195  16  8   8.4   4.6 |   5.8  42.4  200  16  8   7.6   4.2
 12000   6.7  44.1  195  16  8   9.0   4.9 |   6.8  44.2  200  19 10   7.3   4.0
 11500   8.1  46.6  190  17  9   8.7   4.8 |   7.9  46.2  200  21 11   7.6   4.2
 11000   9.3  48.7  195  18  9   8.1   4.4 |   9.0  48.2  195  24 12   7.9   4.3
 10500  10.5  50.9  195  20 10   7.4   4.0 |  10.2  50.4  195  26 14   4.7   2.6
 10250  11.0  51.8  195  21 11   6.8   3.7 |  10.4  50.7  195  27 14   5.6   3.1
 10000  11.6  52.9  195  22 11   7.5   4.1 |  11.1  52.0  190  26 13  11.4   6.3
  9750  12.1  53.8  190  23 12   8.1   4.5 |  11.9  53.4  190  25 13  11.5   6.3
  9500  12.7  54.9  190  23 12   6.1   3.3 |  12.7  54.9  185  25 13   9.2   5.1
  9250  13.0  55.4  185  23 12   3.5   1.9 |  13.2  55.8  180  24 12   6.2   3.4
  9000  13.2  55.8  185  23 12   3.5   1.9 |  13.6  56.5  180  24 12   6.9   3.8
  8750  13.4  56.1  180  21 11   3.7   2.0 |  14.2  57.6  175  22 12   7.7   4.2
  8500  13.6  56.5  175  20 11   2.6   1.4 |  14.7  58.5  170  22 11   5.5   3.0
  8250  13.7  56.7  165  20 10   1.3   0.7 |  14.9  58.8  170  20 11   3.4   1.9
  8000  13.8  56.8  160  20 10   2.1   1.2 |  15.2  59.4  165  19 10   4.2   2.3
  7750  13.9  57.0  155  20 10   3.1   1.7 |  15.5  59.9  165  18  9   5.1   2.8
  7500  14.1  57.4  150  19 10   3.7   2.0 |  15.9  60.6  165  18  9   8.0   4.4
  7250  14.4  57.9  150  18 10   3.8   2.1 |  16.6  61.9  165  17  9   9.6   5.3
  7000  14.6  58.3  145  18  9   3.9   2.2 |  17.2  63.0  165  17  9   9.3   5.1
  6750  14.9  58.8  140  17  9   4.4   2.4 |  17.9  64.2  165  16  8  10.0   5.5
  6500  15.2  59.4  140  15  8   4.4   2.4 |  18.7  65.7  165  16  8  10.5   5.7
  6250  15.5  59.9  140  13  6   4.1   2.3 |  19.5  67.1  165  15  8  10.3   5.6
  6000  15.7  60.3  135  10  5   4.6   2.5 |  20.2  68.4  165  15  8  10.7   5.8
  5750  16.1  61.0  135   9  5   9.3   5.1 |  21.2  70.2  165  15  8  15.9   8.7
  5500  17.0  62.6  130   8  4  15.6   8.6 |  22.6  72.7  165  14  7  23.4  12.8
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/21/2014 at 1500 MDT          |       09/21/2014 at 1800 MDT
                                           |
K index... +27.5  LI... -2.1               | K index... +30.7  LI... -2.7
CAPE... +148.9  CIN... -11.6               | CAPE... +197.8  CIN... -37.3
                                           |
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 -66.1 -87.0  270  35 18   2.7   1.5 | -65.9 -86.6  270  33 17   2.7   1.5
 45000 -60.6 -77.1  265  48 25   5.8   3.2 | -60.1 -76.2  260  47 24   6.1   3.3
 40000 -51.7 -61.1  255  58 30   6.2   3.4 | -51.1 -60.0  255  54 28   5.8   3.2
 38000 -48.0 -54.4  250  49 25   6.2   3.4 | -47.6 -53.7  250  50 26   5.8   3.2
 36000 -44.3 -47.7  250  41 21   6.0   3.3 | -44.2 -47.6  250  46 24   5.5   3.0
 34000 -39.7 -39.5  250  35 18   7.8   4.3 | -39.7 -39.5  250  40 21   7.7   4.2
 32000 -34.4 -29.9  245  30 15   8.4   4.6 | -34.5 -30.1  245  34 18   7.9   4.3
 30000 -29.5 -21.1  235  26 13   8.3   4.6 | -29.3 -20.7  245  32 17   8.7   4.8
 29000 -27.0 -16.6  230  25 13   8.4   4.6 | -26.6 -15.9  245  32 16   8.8   4.8
 28000 -24.6 -12.3  225  24 12   7.9   4.3 | -24.1 -11.4  240  31 16   7.3   4.0
 27000 -22.2  -8.0  220  26 13   7.9   4.3 | -22.0  -7.6  240  29 15   7.0   3.9
 26000 -19.9  -3.8  215  28 14   7.9   4.3 | -19.9  -3.8  240  27 14   7.0   3.9
 25000 -17.6   0.3  215  30 16   7.5   4.1 | -17.8  -0.0  240  25 13   6.9   3.8
 24000 -15.7   3.7  215  29 15   6.1   3.4 | -15.9   3.4  235  26 13   6.0   3.3
 23000 -13.9   7.0  215  28 14   6.1   3.4 | -14.1   6.6  230  27 14   6.0   3.3
 22000 -12.1  10.2  215  26 14   5.6   3.1 | -12.3   9.9  220  29 15   5.6   3.1
 21000 -10.8  12.6  210  27 14   4.6   2.5 | -11.0  12.2  220  29 15   4.2   2.3
 20000  -9.4  15.1  210  27 14   4.6   2.5 |  -9.8  14.4  215  29 15   4.3   2.3
 19500  -8.7  16.3  205  28 14   4.5   2.5 |  -9.2  15.4  215  29 15   4.1   2.3
 19000  -8.0  17.6  205  28 14   4.8   2.7 |  -8.5  16.7  215  28 15   6.6   3.6
 18500  -7.3  18.9  200  28 15   4.9   2.7 |  -7.6  18.3  215  27 14   6.8   3.7
 18000  -6.6  20.1  200  29 15   5.3   2.9 |  -6.7  19.9  215  27 14   6.7   3.7
 17500  -5.7  21.7  200  29 15   6.0   3.3 |  -5.9  21.4  210  27 14   5.9   3.3
 17000  -4.8  23.4  200  30 15   5.9   3.2 |  -5.0  23.0  210  27 14   5.9   3.2
 16500  -3.9  25.0  200  30 15   6.9   3.8 |  -4.1  24.6  210  27 14   7.1   3.9
 16000  -2.9  26.8  200  30 16   6.8   3.7 |  -3.1  26.4  210  27 14   7.1   3.9
 15500  -1.4  29.5  200  30 15   7.0   3.8 |  -1.5  29.3  205  26 14   8.0   4.4
 15000  -0.4  31.3  200  29 15   7.0   3.8 |  -0.4  31.3  205  26 13   7.9   4.3
 14500   0.6  33.1  200  28 14   7.3   4.0 |   0.8  33.4  205  25 13   8.7   4.8
 14000   1.6  34.9  200  26 13   7.3   4.0 |   2.0  35.6  205  24 12   8.8   4.8
 13500   2.7  36.9  200  24 12   8.8   4.8 |   3.3  37.9  205  23 12   9.0   5.0
 13000   4.0  39.2  200  23 12   9.2   5.1 |   4.7  40.5  200  22 11   9.2   5.0
 12500   5.4  41.7  200  22 11   9.9   5.5 |   6.0  42.8  200  20 10   9.3   5.1
 12000   6.9  44.4  200  22 11  10.3   5.7 |   7.4  45.3  200  20 10   9.4   5.2
 11500   8.4  47.1  200  21 11   9.8   5.4 |   8.8  47.8  200  19 10   9.2   5.1
 11000   9.8  49.6  200  20 10   9.2   5.0 |  10.2  50.4  200  18  9   8.7   4.8
 10500  11.2  52.2  200  19 10   5.3   2.9 |  11.5  52.7  200  16  8   5.0   2.7
 10250  11.4  52.5  200  18  9   7.1   3.9 |  11.7  53.1  200  16  8   5.9   3.3
 10000  12.3  54.1  200  18  9  12.9   7.1 |  12.5  54.5  200  15  8  11.6   6.4
  9750  13.2  55.8  200  17  9  11.7   6.4 |  13.3  55.9  200  14  7  10.6   5.8
  9500  14.0  57.2  200  16  8   9.5   5.2 |  14.1  57.4  200  13  7   8.9   4.9
  9250  14.6  58.3  200  16  8   8.6   4.7 |  14.6  58.3  205  12  6   7.6   4.2
  9000  15.4  59.7  200  16  8  11.1   6.1 |  15.2  59.4  205  11  6   9.2   5.1
  8750  16.2  61.2  200  16  8  11.0   6.0 |  15.9  60.6  205  10  5   9.3   5.1
  8500  17.0  62.6  200  16  8  10.0   5.5 |  16.6  61.9  210   9  5   8.9   4.9
  8250  17.7  63.9  200  16  8   9.4   5.2 |  17.2  63.0  215   8  4   8.5   4.6
  8000  18.4  65.1  200  15  8   9.6   5.3 |  17.8  64.0  220   7  4   8.6   4.7
  7750  19.1  66.4  200  15  8   9.8   5.4 |  18.5  65.3  230   7  3   8.6   4.7
  7500  19.9  67.8  200  15  8  10.2   5.6 |  19.1  66.4  235   6  3   9.1   5.0
  7250  20.6  69.1  200  15  8  10.4   5.7 |  19.8  67.6  240   6  3   9.3   5.1
  7000  21.4  70.5  200  15  8  10.1   5.5 |  20.5  68.9  245   6  3   9.4   5.2
  6750  22.1  71.8  200  14  7  10.3   5.6 |  21.2  70.2  250   6  3   9.8   5.4
  6500  22.9  73.2  200  14  7  10.6   5.8 |  21.9  71.4  250   6  3  10.0   5.5
  6250  23.7  74.7  200  14  7  10.7   5.9 |  22.7  72.9  255   6  3  10.0   5.5
  6000  24.5  76.1  200  13  7  10.1   5.5 |  23.4  74.1  255   6  3  10.2   5.6
  5750  25.3  77.5  200  13  7  11.5   6.3 |  24.1  75.4  260   5  3   8.8   4.8
  5500  26.2  79.2  200  12  6  13.6   7.5 |  24.7  76.5  260   5  3   7.2   3.9
  5250  27.2  81.0  205  12  6  11.9   6.5 |  25.2  77.4  260   5  3   8.4   4.6
  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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