Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 261239
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0639 MDT Tuesday, September 26, 2017

This forecast is for Tuesday, September 26, 2017:

If the trigger temperature of 59.1 F/15.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 619 ft/min (3.1 m/s)
   Maximum height of thermals.................. 13228 ft MSL (8389 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... 1115 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................. 11623 ft MSL (6784 ft AGL)
Thermal soaring outlook for Wednesday 09/27.... Good

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

Remarks...

Sunrise/Sunset.................... 07:05:47 / 19:05:45 MDT
Total possible sunshine........... 11 hr 59 min 58 sec (719 min 58 sec)
Altitude of sun at 13:05:17 MDT... 49.35 degrees

Upper air data from rawinsonde observation taken on 09/26/2017 at 0600 MDT

Freezing level.................. 10743 ft MSL (5904 ft AGL)
Convective condensation level... 17198 ft MSL (12359 ft AGL)
Lifted condensation level....... 15181 ft MSL (10342 ft AGL)
Lifted index.................... +2.9
K index......................... -14.1

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  -58.2 -72.8   235   30   15   5.0   2.8  102.2 216.0    46.4      M    M
 45000  -54.2 -65.6   220   40   20   4.4   2.4   83.1 181.6    38.1      M    M
 40000  -51.7 -61.1   225   46   24   5.5   3.0   64.0 147.3    28.2      M    M
 38000  -50.3 -58.5   225   37   19  -8.2  -4.5   57.4 135.3    24.5      M    M
 36000  -50.6 -59.1   225   36   19  -0.2  -0.1   48.4 119.1    18.9      M    M
 34000  -49.8 -57.6   225   39   20   2.5   1.4   41.3 106.4    14.4      M    M
 32000  -45.7 -50.3   220   42   22   9.0   5.0   37.7  99.9    12.1      M    M
 30000  -40.7 -41.3   220   40   21   7.7   4.2   36.7  98.0    11.7      M    M
 29000  -38.5 -37.3   220   41   21   6.7   3.7   35.7  96.2    11.1      M    M
 28000  -36.4 -33.5   225   41   21   6.7   3.7   34.6  94.4    10.4      M    M
 27000  -33.9 -29.0   225   42   22  10.3   5.6   34.2  93.5    10.1      M    M
 26000  -31.5 -24.7   225   38   20   7.3   4.0   33.5  92.3     9.7      M    M
 25000  -29.3 -20.7   225   35   18   6.6   3.6   32.6  90.7     9.1      M    M
 24000  -27.1 -16.8   230   32   17   8.5   4.7   31.8  89.2     8.5      M    M
 23000  -24.5 -12.1   230   29   15   8.3   4.5   31.3  88.4     8.3      M    M
 22000  -21.9  -7.4   230   25   13   9.7   5.3   31.0  87.7     8.1      M    M
 21000  -19.4  -2.9   235   22   11   7.8   4.3   30.3  86.6     7.6      M    M
 20000  -17.1   1.2   235   18    9   7.7   4.2   29.7  85.4     7.2      M    M
 19500  -16.0   3.2   235   19   10   7.6   4.2   29.3  84.7     6.9      M    M
 19000  -14.8   5.4   240   21   11   7.8   4.3   28.9  84.1     6.6      M    M
 18500  -13.8   7.2   240   22   11   5.6   3.1   28.4  83.1     6.2      M    M
 18000  -12.8   9.0   235   22   11   7.3   4.0   27.8  82.0     5.8      M    M
 17500  -11.7  10.9   230   22   11   7.7   4.2   27.4  81.3     5.5      M    M
 17000   -9.9  14.2   225   22   12   7.6   4.2   26.9  80.4     5.1      M    M
 16500   -9.2  15.4   225   23   12   3.3   1.8   26.1  79.0     4.4      M    M
 16000   -8.6  16.5   220   23   12   4.4   2.4   25.1  77.2     3.5      M    M
 15500   -7.7  18.1   215   24   12   7.4   4.0   24.5  76.2     3.0      M    M
 15000   -6.6  20.1   215   24   12   7.1   3.9   24.1  75.4     2.7      M    M
 14500   -5.5  22.1   215   21   11   5.3   2.9   23.7  74.6     2.3      M    M
 14000   -5.5  22.1   215   19   10   0.2   0.1   22.1  71.9     0.9      M    M
 13500   -4.7  23.5   215   15    8   7.6   4.2   21.4  70.5     0.2      M    M
 13000   -3.8  25.2   220   12    6   4.4   2.4   20.8  69.5    -0.4    597  3.0
 12500   -3.3  26.1   220    9    5   0.2   0.1   19.8  67.6    -1.4    569  2.9
 12000   -3.4  25.9   225    6    3   7.6   4.2   18.4  65.1    -2.9    555  2.8
 11500   -2.0  28.4   210    5    3   9.0   4.9   18.3  64.9    -3.0    499  2.5
 11000   -0.7  30.7   195    5    3   9.1   5.0   18.2  64.7    -3.2    444  2.3
 10500    0.7  33.3   180    6    3   9.2   5.1   18.1  64.5    -3.3    389  2.0
 10250    1.3  34.3   170    6    3   5.9   3.2   18.0  64.3    -3.4    364  1.8
 10000    1.5  34.7   160    6    3   2.4   1.3   17.5  63.4    -3.9    350  1.8
  9750    1.7  35.1   145    5    3   2.6   1.4   16.9  62.4    -4.5    337  1.7
  9500    1.9  35.4   130    5    3   2.2   1.2   16.3  61.4    -5.1    325  1.6
  9250    2.1  35.8   115    5    3   5.9   3.3   15.8  60.5    -5.6    310  1.6
  9000    2.7  36.9   100    6    3   9.0   4.9   15.7  60.3    -5.7    284  1.4
  8750    3.3  37.9   095    6    3   8.1   4.5   15.6  60.1    -5.8    258  1.3
  8500    3.9  39.0   090    7    4   8.5   4.7   15.5  59.9    -6.0    232  1.2
  8250    4.6  40.3   085    7    4   8.0   4.4   15.4  59.7    -6.1    206  1.0
  8000    5.1  41.2   080    8    4   4.7   2.6   15.1  59.3    -6.3    184  0.9
  7750    5.3  41.5   080    8    4   2.4   1.3   14.6  58.3    -6.8    170  0.9
  7500    5.5  41.9   075    8    4   3.9   2.2   14.1  57.4    -7.4    156  0.8
  7250    5.9  42.6   075    7    4   5.9   3.2   13.7  56.7    -7.7    137  0.7
  7000    6.3  43.3   070    7    4   6.4   3.5   13.5  56.3    -8.0    116  0.6
  6750    6.8  44.2   070    7    3   6.3   3.4   13.2  55.8    -8.3     95  0.5
  6500    7.3  45.1   070    6    3   6.3   3.5   13.0  55.3    -8.6     73  0.4
  6250    7.7  45.9   065    6    3   6.3   3.4   12.7  54.9    -8.9     52  0.3
  6000    8.2  46.8   065    5    3   6.4   3.5   12.4  54.4    -9.1     30  0.2
  5750    8.7  47.7   070    5    2   5.9   3.2   12.2  53.9    -9.4      9  0.0
  5500    9.1  48.4   075    4    2   8.0   4.4   11.9  53.5    -9.7      M    M
  5250    9.6  49.3   085    4    2   0.2   0.1   11.7  53.0   -10.0      M    M
  5000    8.8  47.8   095    4    2 -22.8 -12.5   10.1  50.2   -11.6      M    M

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

           09/26/2017 at 0900 MDT          |       09/26/2017 at 1200 MDT
                                           |
K index... -0.5  LI... +5.1                | K index... +5.0  LI... +5.4
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.1 -70.8  230  26 14   2.3   1.3 | -56.8 -70.2  230  29 15   1.9   1.0
 45000 -53.6 -64.5  225  36 19   1.7   0.9 | -54.0 -65.2  225  40 21   1.8   1.0
 40000 -51.1 -60.0  225  39 20   1.6   0.9 | -51.2 -60.2  220  44 23   1.8   1.0
 38000 -50.6 -59.1  225  38 19   0.6   0.3 | -50.3 -58.5  220  40 21   1.5   0.8
 36000 -50.2 -58.4  225  35 18   0.6   0.3 | -49.4 -56.9  220  35 18   1.5   0.8
 34000 -48.8 -55.8  225  34 17   5.6   3.1 | -47.9 -54.2  220  31 16   4.2   2.3
 32000 -45.5 -49.9  220  35 18   5.6   3.1 | -45.1 -49.2  220  30 15   4.2   2.3
 30000 -40.9 -41.6  220  34 17   8.3   4.6 | -41.3 -42.3  220  30 15   8.8   4.8
 29000 -38.4 -37.1  225  32 17   8.3   4.6 | -38.6 -37.5  220  30 16   8.8   4.9
 28000 -35.9 -32.6  225  31 16   8.3   4.5 | -36.0 -32.8  215  31 16   8.8   4.8
 27000 -33.5 -28.3  225  30 16   7.5   4.1 | -33.4 -28.1  215  30 16   8.1   4.4
 26000 -31.3 -24.3  225  30 15   7.6   4.2 | -31.0 -23.8  215  29 15   8.1   4.5
 25000 -29.0 -20.2  225  30 15   7.6   4.2 | -28.6 -19.5  215  28 14   8.1   4.5
 24000 -26.7 -16.1  230  29 15   8.4   4.6 | -26.1 -15.0  210  26 13   8.2   4.5
 23000 -24.2 -11.6  230  26 13   8.3   4.6 | -23.6 -10.5  210  23 12   8.2   4.5
 22000 -21.7  -7.1  230  23 12   8.3   4.6 | -21.1  -6.0  210  21 11   8.2   4.5
 21000 -19.3  -2.7  230  20 10   7.4   4.1 | -18.8  -1.8  210  19 10   6.9   3.8
 20000 -17.0   1.4  230  19 10   7.5   4.1 | -16.7   1.9  205  17  9   7.0   3.8
 19500 -15.9   3.4  225  18  9   7.5   4.1 | -15.7   3.7  205  16  8   7.0   3.8
 19000 -14.8   5.4  225  17  9   7.4   4.1 | -14.6   5.7  205  15  8   7.0   3.8
 18500 -13.7   7.3  225  17  9   7.5   4.1 | -13.6   7.5  210  15  8   6.4   3.5
 18000 -12.5   9.5  230  17  9   7.5   4.1 | -12.6   9.3  210  14  7   6.5   3.6
 17500 -11.4  11.5  230  17  9   7.3   4.0 | -11.7  10.9  215  14  7   6.2   3.4
 17000 -10.3  13.5  230  17  9   7.1   3.9 | -10.8  12.6  220  14  7   6.0   3.3
 16500  -9.3  15.3  230  18  9   7.1   3.9 |  -9.9  14.2  225  15  8   6.1   3.3
 16000  -8.3  17.1  230  19 10   6.3   3.5 |  -9.0  15.8  225  16  8   6.4   3.5
 15500  -7.3  18.9  230  19 10   6.4   3.5 |  -8.1  17.4  230  17  9   6.3   3.5
 15000  -6.4  20.5  230  20 10   5.9   3.2 |  -6.5  20.3  230  19 10   7.8   4.3
 14500  -5.1  22.8  230  20 10   5.9   3.2 |  -5.3  22.5  230  19 10   7.8   4.3
 14000  -4.3  24.3  225  19 10   5.0   2.8 |  -4.2  24.4  230  19 10   7.6   4.2
 13500  -3.6  25.5  225  19 10   5.3   2.9 |  -3.0  26.6  225  19 10   7.8   4.3
 13000  -3.0  26.6  220  17  9   3.4   1.8 |  -2.1  28.2  225  17  9   5.3   2.9
 12500  -2.5  27.5  215  13  7   3.5   1.9 |  -1.3  29.7  220  15  8   5.7   3.1
 12000  -1.9  28.6  205  10  5   5.7   3.2 |  -0.6  30.9  215  13  6   4.2   2.3
 11500  -1.1  30.0  200   8  4   5.6   3.1 |   0.0  32.0  210  10  5   4.1   2.2
 11000  -0.2  31.6  185   6  3   7.2   4.0 |   0.9  33.6  195   7  4   7.4   4.0
 10500   0.9  33.6  165   5  3   7.9   4.3 |   1.9  35.4  180   6  3   7.9   4.3
 10250   1.4  34.5  155   5  2   4.3   2.3 |   2.4  36.3  165   6  3   4.3   2.3
 10000   1.6  34.9  150   4  2   4.7   2.6 |   2.6  36.7  160   5  3   5.1   2.8
  9750   2.2  36.0  140   4  2   8.7   4.8 |   3.3  37.9  150   5  2   9.4   5.2
  9500   2.8  37.0  125   4  2   7.7   4.2 |   3.9  39.0  140   4  2   8.3   4.6
  9250   3.3  37.9  115   4  2   7.1   3.9 |   4.5  40.1  130   4  2   6.5   3.6
  9000   3.8  38.8  110   4  2   6.5   3.6 |   4.9  40.8  115   4  2   6.2   3.4
  8750   4.3  39.7  100   4  2   7.0   3.8 |   5.4  41.7  105   4  2   7.6   4.2
  8500   4.8  40.6  095   4  2   6.4   3.5 |   6.0  42.8  090   4  2   7.2   3.9
  8250   5.2  41.4  090   4  2   5.1   2.8 |   6.5  43.7  080   4  2   7.3   4.0
  8000   5.6  42.1  090   4  2   4.3   2.3 |   7.0  44.6  075   3  2   6.7   3.7
  7750   5.9  42.6  090   4  2   4.3   2.4 |   7.5  45.5  065   3  2   5.6   3.1
  7500   6.2  43.2  085   4  2   2.6   1.4 |   7.9  46.2  060   3  2   6.7   3.7
  7250   6.3  43.3  085   5  2   1.0   0.6 |   8.5  47.3  055   3  1   8.0   4.4
  7000   6.4  43.5  080   5  2   1.1   0.6 |   9.1  48.4  050   2  1   7.5   4.1
  6750   6.5  43.7  080   5  3   0.3   0.1 |   9.6  49.3  045   2  1   7.9   4.3
  6500   6.5  43.7  080   5  3  -0.4  -0.2 |  10.3  50.5  040   2  1   9.8   5.4
  6250   6.4  43.5  080   5  3   0.2   0.1 |  11.1  52.0  040   2  1  10.9   6.0
  6000   6.4  43.5  080   5  3  -1.9  -1.0 |  11.9  53.4  040   1  1  10.1   5.5
  5750   6.3  43.3  080   5  2   2.9   1.6 |  12.6  54.7  035   1  1  11.8   6.5
  5500   6.9  44.4  080   4  2   9.6   5.3 |  13.6  56.5  035   1  1  14.1   7.7
  5250   7.5  45.5  080   4  2   4.3   2.4 |  14.7  58.5  040   1  1  12.4   6.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/26/2017 at 1500 MDT          |       09/26/2017 at 1800 MDT
                                           |
K index... +14.7  LI... +2.9               | K index... +20.3  LI... +1.8
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.1 -70.8  230  26 13   2.0   1.1 | -57.3 -71.1  225  25 13   2.4   1.3
 45000 -54.1 -65.4  230  37 19   2.1   1.2 | -53.9 -65.0  225  35 18   1.7   1.0
 40000 -50.9 -59.6  220  43 22   2.1   1.2 | -51.2 -60.2  225  41 21   1.8   1.0
 38000 -50.0 -58.0  220  40 21   1.3   0.7 | -50.4 -58.7  225  41 21   1.4   0.7
 36000 -49.2 -56.6  220  36 18   1.3   0.7 | -49.6 -57.3  225  39 20   1.4   0.7
 34000 -47.8 -54.0  215  31 16   4.0   2.2 | -47.6 -53.7  230  35 18   5.0   2.7
 32000 -45.1 -49.2  215  27 14   4.0   2.2 | -44.6 -48.3  225  28 14   5.0   2.8
 30000 -41.4 -42.5  215  25 13   8.7   4.8 | -40.7 -41.3  225  23 12   8.0   4.4
 29000 -38.8 -37.8  215  26 13   8.7   4.8 | -38.3 -36.9  225  22 11   8.0   4.4
 28000 -36.2 -33.2  210  26 14   8.7   4.8 | -35.9 -32.6  225  22 11   8.0   4.4
 27000 -33.6 -28.5  210  26 14   8.7   4.8 | -33.5 -28.3  225  22 11   8.3   4.6
 26000 -31.0 -23.8  210  26 13   8.7   4.8 | -31.0 -23.8  220  24 12   8.3   4.6
 25000 -28.4 -19.1  210  25 13   8.7   4.8 | -28.5 -19.3  220  26 13   8.3   4.6
 24000 -25.8 -14.4  210  25 13   7.5   4.1 | -26.1 -15.0  220  26 13   7.6   4.2
 23000 -23.5 -10.3  210  23 12   7.6   4.2 | -23.8 -10.8  220  23 12   7.7   4.2
 22000 -21.2  -6.2  215  22 11   7.6   4.2 | -21.4  -6.5  220  20 10   7.7   4.2
 21000 -19.0  -2.2  215  21 11   6.7   3.7 | -19.2  -2.6  220  18  9   7.0   3.8
 20000 -17.0   1.4  210  19 10   6.8   3.7 | -17.1   1.2  215  18  9   7.0   3.8
 19500 -16.0   3.2  205  19 10   6.8   3.7 | -16.1   3.0  215  18  9   7.0   3.8
 19000 -15.0   5.0  205  18  9   6.8   3.7 | -15.0   5.0  215  17  9   7.0   3.9
 18500 -14.0   6.8  200  18  9   5.7   3.1 | -14.2   6.4  210  18  9   4.6   2.5
 18000 -13.2   8.2  200  17  9   5.8   3.2 | -13.5   7.7  205  18  9   4.9   2.7
 17500 -12.3   9.9  195  17  9   6.4   3.5 | -12.8   9.0  200  18  9   6.3   3.5
 17000 -11.4  11.5  200  17  9   6.7   3.7 | -11.8  10.8  195  18  9   7.1   3.9
 16500 -10.4  13.3  200  17  9   6.8   3.8 | -10.8  12.6  190  18  9   7.5   4.1
 16000  -9.4  15.1  200  16  8   7.1   3.9 |  -9.5  14.9  185  18  9   9.1   5.0
 15500  -7.9  17.8  205  16  8   7.8   4.3 |  -7.6  18.3  185  17  9   8.8   4.8
 15000  -6.6  20.1  205  16  8   8.7   4.8 |  -6.3  20.7  185  16  8   8.5   4.7
 14500  -5.3  22.5  205  16  8   8.7   4.8 |  -5.1  22.8  185  14  7   8.4   4.6
 14000  -4.1  24.6  205  15  8   7.9   4.3 |  -3.9  25.0  185  13  7   7.9   4.3
 13500  -2.9  26.8  205  14  7   7.9   4.3 |  -2.7  27.1  180  12  6   7.9   4.4
 13000  -1.7  28.9  205  13  7   8.1   4.4 |  -1.4  29.5  175  10  5   8.8   4.8
 12500  -0.5  31.1  205  12  6   8.1   4.4 |  -0.1  31.8  175   9  5   8.7   4.8
 12000   0.7  33.3  205  11  5   7.7   4.2 |   1.2  34.2  170   8  4   8.5   4.7
 11500   1.8  35.2  210   9  5   7.9   4.3 |   2.5  36.5  165   7  3   8.5   4.7
 11000   2.9  37.2  210   7  4   6.6   3.6 |   3.8  38.8  160   5  3   8.3   4.5
 10500   3.9  39.0  210   5  3   6.9   3.8 |   5.0  41.0  150   4  2   7.4   4.1
 10250   4.4  39.9  210   4  2   5.2   2.9 |   5.5  41.9  145   3  1   5.5   3.0
 10000   4.8  40.6  210   3  2   6.5   3.5 |   6.0  42.8  140   2  1   7.8   4.3
  9750   5.4  41.7  210   2  1   8.8   4.8 |   6.7  44.1  130   2  1   9.7   5.3
  9500   6.0  42.8  215   1  1   8.2   4.5 |   7.4  45.3  105   1  1   9.1   5.0
  9250   6.6  43.9  235   1  0   7.0   3.8 |   8.0  46.4  080   1  1   6.8   3.7
  9000   7.1  44.8  000   0  0   6.6   3.6 |   8.5  47.3  055   1  1   6.6   3.6
  8750   7.6  45.7  340   1  0   7.3   4.0 |   9.0  48.2  035   2  1   8.1   4.5
  8500   8.2  46.8  355   1  1   7.3   4.0 |   9.6  49.3  020   2  1   7.8   4.3
  8250   8.7  47.7  355   2  1   7.8   4.3 |  10.2  50.4  010   2  1   8.6   4.7
  8000   9.3  48.7  350   2  1   8.8   4.8 |  10.9  51.6  355   2  1   7.5   4.1
  7750  10.0  50.0  350   2  1   9.6   5.3 |  11.3  52.3  340   3  1   5.7   3.1
  7500  10.7  51.3  345   2  1   9.6   5.3 |  11.8  53.2  330   3  1   7.0   3.9
  7250  11.4  52.5  340   2  1   9.8   5.4 |  12.4  54.3  320   3  1   8.3   4.6
  7000  12.2  54.0  340   2  1   9.6   5.2 |  13.0  55.4  315   3  2   8.2   4.5
  6750  12.9  55.2  335   2  1   9.5   5.2 |  13.6  56.5  305   3  2   8.5   4.7
  6500  13.6  56.5  330   2  1  10.6   5.8 |  14.3  57.7  300   3  2   9.8   5.4
  6250  14.5  58.1  330   2  1  11.5   6.3 |  15.1  59.2  295   3  2  10.6   5.8
  6000  15.3  59.5  325   2  1  10.6   5.8 |  15.8  60.4  295   3  2  10.1   5.6
  5750  16.1  61.0  320   2  1  12.0   6.6 |  16.5  61.7  290   3  2   8.2   4.5
  5500  17.1  62.8  320   2  1  14.3   7.9 |  17.1  62.8  290   3  2   6.7   3.7
  5250  18.2  64.8  325   2  1  13.2   7.2 |  17.6  63.7  295   3  2   7.6   4.2
  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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