Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 151256
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0656 MDT Tuesday, May 15, 2018

This forecast is for Tuesday, May 15, 2018:

If the trigger temperature of 72.1 F/22.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1288 ft/min (6.5 m/s)
   Maximum height of thermals.................. 19502 ft MSL (14663 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 17913 ft MSL (13074 ft AGL)
Thermal soaring outlook for Wednesday 05/16.... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:01:11 / 20:19:38 MDT
Total possible sunshine........... 14 hr 18 min 26 sec (858 min 26 sec)
Altitude of sun at 13:10:35 MDT... 69.86 degrees

Upper air data from rawinsonde observation taken on 05/15/2018 at 0600 MDT

Freezing level.................. 12819 ft MSL (7980 ft AGL)
Convective condensation level... 17214 ft MSL (12375 ft AGL)
Lifted condensation level....... 18672 ft MSL (13833 ft AGL)
Lifted index.................... +0.7
K index......................... +6.7

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  -62.2 -80.0   250   34   18  -5.0  -2.8   94.5 202.1    38.3      M    M
 45000  -57.5 -71.5   260   32   16   5.3   2.9   77.8 172.0    30.7      M    M
 40000  -55.2 -67.4   240   32   17  -1.8  -1.0   58.5 137.3    20.2      M    M
 38000  -53.7 -64.7   235   37   19   1.5   0.8   51.8 125.3    16.3      M    M
 36000  -51.6 -60.9   230   41   21   3.8   2.1   45.4 113.7    12.2      M    M
 34000  -48.0 -54.4   230   41   21   7.1   3.9   42.2 107.9    10.3      M    M
 32000  -44.0 -47.2   235   39   20   6.3   3.5   39.7 103.5     8.7      M    M
 30000  -40.1 -40.2   240   41   21   6.5   3.5   37.1  98.7     7.0      M    M
 29000  -38.2 -36.8   240   41   21   7.7   4.2   35.8  96.4     6.1      M    M
 28000  -35.4 -31.7   245   42   21   8.3   4.6   35.6  96.1     6.0      M    M
 27000  -33.1 -27.6   245   42   22   7.7   4.2   34.8  94.6     5.4      M    M
 26000  -30.7 -23.3   245   39   20   8.9   4.9   34.1  93.4     5.0      M    M
 25000  -28.1 -18.6   245   35   18   7.7   4.2   33.7  92.6     4.7      M    M
 24000  -25.7 -14.3   240   34   18   9.0   4.9   33.0  91.5     4.2      M    M
 23000  -23.0  -9.4   240   30   15   8.2   4.5   32.7  90.9     4.0      M    M
 22000  -20.6  -5.1   240   26   13   7.8   4.3   31.9  89.5     3.4      M    M
 21000  -18.3  -0.9   240   21   11   7.6   4.2   31.3  88.3     2.9      M    M
 20000  -16.8   1.8   225   24   12   2.2   1.2   29.6  85.3     1.5      M    M
 19500  -16.5   2.3   220   23   12   1.3   0.7   28.2  82.8     0.4      M    M
 19000  -16.4   2.5   205   23   12   5.9   3.2   25.9  78.6    -1.7   1365  6.9
 18500  -15.3   4.5   205   23   12   2.4   1.3   25.5  77.9    -2.1   1318  6.7
 18000  -14.7   5.5   210   22   11   9.4   5.2   24.6  76.3    -3.0   1285  6.5
 17500  -13.3   8.1   210   22   11   9.5   5.2   24.5  76.2    -3.1   1227  6.2
 17000  -11.8  10.8   210   22   11   9.5   5.2   24.5  76.1    -3.1   1170  5.9
 16500  -10.4  13.3   215   21   11   9.5   5.2   24.5  76.1    -3.1   1112  5.6
 16000   -9.0  15.8   215   21   11   9.5   5.2   24.5  76.1    -3.1   1054  5.4
 15500   -7.5  18.5   215   20   10   9.5   5.2   24.4  76.0    -3.2    996  5.1
 15000   -6.1  21.0   210   18    9   9.5   5.2   24.4  75.9    -3.3    939  4.8
 14500   -4.7  23.5   210   17    9   9.5   5.2   24.3  75.8    -3.3    881  4.5
 14000   -3.2  26.2   205   16    8   9.4   5.2   24.3  75.8    -3.4    823  4.2
 13500   -1.8  28.8   200   15    8   9.4   5.2   24.2  75.6    -3.5    766  3.9
 13000   -0.4  31.3   200   14    7   9.4   5.2   24.2  75.5    -3.6    709  3.6
 12500    1.0  33.8   195   13    7   9.4   5.2   24.1  75.4    -3.6    653  3.3
 12000    2.4  36.3   190   12    6   9.4   5.1   24.1  75.4    -3.7    596  3.0
 11500    3.8  38.8   185   10    5   8.9   4.9   24.1  75.3    -3.8    539  2.7
 11000    5.0  41.0   175    8    4   8.4   4.6   23.8  74.9    -4.1    488  2.5
 10500    6.2  43.2   160    7    3   8.5   4.7   23.6  74.5    -4.3    437  2.2
 10250    6.8  44.2   155    6    3   8.2   4.5   23.5  74.3    -4.4    411  2.1
 10000    7.4  45.3   150    6    3   7.8   4.3   23.4  74.0    -4.6    385  2.0
  9750    8.0  46.4   150    7    4   7.8   4.3   23.2  73.8    -4.7    360  1.8
  9500    8.6  47.5   155    8    4   7.8   4.3   23.0  73.5    -4.9    335  1.7
  9250    9.2  48.6   155    8    4   7.8   4.3   22.9  73.2    -5.0    310  1.6
  9000    9.8  49.6   155    9    5   7.8   4.3   22.8  73.0    -5.2    284  1.4
  8750   10.4  50.7   155    9    5   7.8   4.3   22.6  72.7    -5.3    259  1.3
  8500   11.0  51.8   160    9    5   7.5   4.1   22.4  72.4    -5.5    234  1.2
  8250   11.6  52.9   160   10    5   8.8   4.8   22.3  72.1    -5.6    209  1.1
  8000   12.2  54.0   165   10    5   4.0   2.2   22.1  71.8    -5.8    184  0.9
  7750   12.1  53.8   155    9    5  -0.7  -0.4   21.4  70.5    -6.6    177  0.9
  7500   12.1  53.8   140    8    4  -0.7  -0.4   20.6  69.1    -7.4    172  0.9
  7250   12.0  53.6   125    8    4   3.2   1.8   19.9  67.8    -8.2    166  0.8
  7000   12.5  54.5   110    9    5   8.0   4.4   19.6  67.4    -8.5    144  0.7
  6750   13.0  55.4   100   10    5   7.4   4.0   19.5  67.0    -8.7    121  0.6
  6500   13.6  56.5   095   10    5   7.5   4.1   19.3  66.7    -8.9     97  0.5
  6250   14.0  57.2   095   11    6   4.7   2.6   19.1  66.3    -9.2     76  0.4
  6000   14.3  57.7   090   12    6   2.7   1.5   18.5  65.4    -9.7     62  0.3
  5750   14.5  58.1   090   11    6   3.1   1.7   18.0  64.5   -10.3     48  0.2
  5500   14.7  58.5   090   10    5   3.6   2.0   17.5  63.6   -10.8     35  0.2
  5250   14.9  58.8   090    9    5   1.2   0.6   17.0  62.7   -11.4     21  0.1
  5000   14.3  57.7   090    8    4 -18.4 -10.1   15.8  60.5   -12.7     30  0.2

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

           05/15/2018 at 0900 MDT          |       05/15/2018 at 1200 MDT
                                           |
K index... +7.0  LI... +4.0                | K index... +5.5  LI... +4.2
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 -60.0 -76.0  265  29 15   2.4   1.3 | -59.7 -75.5  265  27 14   2.7   1.5
 45000 -56.6 -69.9  255  34 18   1.5   0.8 | -55.9 -68.6  260  32 16   0.9   0.5
 40000 -54.3 -65.7  245  24 13   1.3   0.7 | -54.6 -66.3  245  23 12   0.6   0.4
 38000 -52.5 -62.5  240  25 13   3.4   1.8 | -52.8 -63.0  240  21 11   3.4   1.9
 36000 -50.5 -58.9  240  26 13   3.4   1.8 | -50.7 -59.3  240  19 10   3.4   1.9
 34000 -47.9 -54.2  235  27 14   5.7   3.1 | -48.2 -54.8  235  20 10   5.2   2.9
 32000 -44.4 -47.9  240  29 15   5.7   3.1 | -45.0 -49.0  235  23 12   5.2   2.9
 30000 -40.5 -40.9  240  30 15   7.7   4.2 | -41.1 -42.0  230  25 13   8.4   4.6
 29000 -38.2 -36.8  240  30 15   7.7   4.2 | -38.6 -37.5  235  25 13   8.4   4.6
 28000 -35.9 -32.6  245  30 15   7.7   4.2 | -35.4 -31.7  235  24 13   8.4   4.6
 27000 -32.9 -27.2  245  30 15   8.5   4.7 | -32.8 -27.0  235  24 12   8.9   4.9
 26000 -30.3 -22.5  245  29 15   8.5   4.7 | -30.2 -22.4  235  24 12   8.9   4.9
 25000 -27.8 -18.0  245  28 15   8.5   4.7 | -27.5 -17.5  235  24 12   8.9   4.9
 24000 -25.2 -13.4  240  27 14   8.2   4.5 | -24.9 -12.8  235  23 12   8.3   4.6
 23000 -22.8  -9.0  240  25 13   8.2   4.5 | -22.4  -8.3  235  23 12   8.3   4.6
 22000 -20.3  -4.5  235  23 12   8.1   4.5 | -19.9  -3.8  230  22 11   8.3   4.5
 21000 -18.2  -0.8  230  22 11   6.0   3.3 | -17.7   0.1  230  22 11   6.2   3.4
 20000 -16.4   2.5  225  22 11   5.9   3.2 | -15.9   3.4  230  23 12   6.2   3.4
 19500 -15.6   3.9  225  22 11   5.9   3.2 | -15.0   5.0  230  23 12   6.2   3.4
 19000 -14.7   5.5  220  22 11   5.7   3.1 | -14.0   6.8  230  23 12   6.3   3.5
 18500 -14.0   6.8  215  22 11   3.6   2.0 | -13.0   8.6  230  23 12   6.9   3.8
 18000 -13.5   7.7  215  21 11   3.7   2.0 | -12.0  10.4  230  23 12   6.9   3.8
 17500 -12.9   8.8  210  21 11   5.6   3.1 | -11.0  12.2  230  23 12   5.7   3.1
 17000 -12.0  10.4  210  21 11   6.2   3.4 | -10.2  13.6  225  22 11   5.6   3.0
 16500 -11.2  11.8  205  21 11   7.3   4.0 |  -9.4  15.1  220  21 11   5.5   3.0
 16000  -9.9  14.2  205  20 10   9.5   5.2 |  -8.6  16.5  215  20 10   5.4   3.0
 15500  -8.5  16.7  205  19 10   9.5   5.2 |  -7.9  17.8  210  19 10   5.5   3.0
 15000  -7.1  19.2  205  18  9   9.6   5.3 |  -6.8  19.8  205  18  9   8.9   4.9
 14500  -5.6  21.9  205  17  9   9.6   5.3 |  -5.6  21.9  205  17  9   8.6   4.7
 14000  -4.2  24.4  205  16  8   9.1   5.0 |  -4.3  24.3  200  16  8   9.1   5.0
 13500  -2.8  27.0  205  15  8   9.1   5.0 |  -2.2  28.0  195  14  7   9.1   5.0
 13000  -0.8  30.6  205  13  7   8.8   4.8 |  -0.9  30.4  195  13  7   9.0   4.9
 12500   0.5  32.9  205  12  6   8.8   4.8 |   0.4  32.7  195  13  7   9.0   4.9
 12000   1.8  35.2  205  10  5   9.0   4.9 |   1.8  35.2  195  12  6   9.2   5.0
 11500   3.2  37.8  205   9  5   9.0   4.9 |   3.2  37.8  195  12  6   9.2   5.0
 11000   4.4  39.9  200   9  5   7.6   4.1 |   4.5  40.1  195  11  6   8.6   4.7
 10500   5.6  42.1  200   9  4   5.1   2.8 |   5.8  42.4  195  11  5   5.9   3.2
 10250   5.9  42.6  195   8  4   5.7   3.1 |   6.2  43.2  195  10  5   6.6   3.6
 10000   6.6  43.9  195   9  4  10.2   5.6 |   6.9  44.4  195  10  5  10.7   5.9
  9750   7.3  45.1  190   9  5   9.5   5.2 |   7.6  45.7  195  10  5   9.7   5.3
  9500   8.0  46.4  185   9  5   9.5   5.2 |   8.4  47.1  190   9  5   9.5   5.2
  9250   8.7  47.7  185  10  5   7.4   4.1 |   9.0  48.2  190   9  5   8.6   4.7
  9000   9.2  48.6  180  10  5   6.9   3.8 |   9.7  49.5  190   9  4   9.5   5.2
  8750   9.7  49.5  180  11  5   7.9   4.3 |  10.4  50.7  190   8  4  10.3   5.6
  8500  10.3  50.5  175  11  6   7.2   4.0 |  11.2  52.2  190   8  4   9.9   5.4
  8250  10.8  51.4  170  11  6   6.4   3.5 |  11.9  53.4  190   8  4   9.7   5.3
  8000  11.3  52.3  170  12  6   5.6   3.1 |  12.6  54.7  190   8  4   9.8   5.4
  7750  11.7  53.1  165  12  6   5.5   3.0 |  13.4  56.1  190   8  4  10.1   5.5
  7500  12.1  53.8  165  12  6   4.7   2.6 |  14.1  57.4  190   8  4  10.1   5.5
  7250  12.4  54.3  160  11  6   4.0   2.2 |  14.9  58.8  190   8  4  10.3   5.6
  7000  12.7  54.9  160  11  5   3.5   1.9 |  15.7  60.3  190   8  4  10.1   5.5
  6750  12.9  55.2  160  10  5   2.6   1.4 |  16.4  61.5  190   8  4  10.2   5.6
  6500  13.1  55.6  155   8  4   3.9   2.1 |  17.2  63.0  190   8  4  11.0   6.0
  6250  13.4  56.1  155   7  4   4.8   2.7 |  18.1  64.6  195   7  4  12.2   6.7
  6000  13.7  56.7  150   6  3   4.7   2.6 |  18.9  66.0  195   7  4   9.7   5.3
  5750  14.1  57.4  145   5  2   8.7   4.8 |  19.6  67.3  195   7  4  11.8   6.5
  5500  15.0  59.0  140   5  2  12.4   6.8 |  20.8  69.4  195   7  4  17.5   9.6
  5250  15.8  60.4  140   4  2  10.3   5.6 |  22.0  71.6  195   7  3  15.2   8.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/15/2018 at 1500 MDT          |       05/15/2018 at 1800 MDT
                                           |
K index... +11.6  LI... +3.1               | K index... +15.0  LI... +2.1
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 -59.9 -75.8  265  29 15   3.2   1.7 | -59.7 -75.5  265  27 14   3.2   1.7
 45000 -55.7 -68.3  260  35 18   0.1   0.1 | -55.6 -68.1  265  31 16  -0.6  -0.4
 40000 -55.6 -68.1  260  26 14  -0.4  -0.2 | -56.5 -69.7  270  30 16  -1.2  -0.7
 38000 -53.5 -64.3  260  23 12   4.2   2.3 | -54.1 -65.4  270  27 14   4.8   2.6
 36000 -50.9 -59.6  265  19 10   4.2   2.3 | -51.3 -60.3  275  23 12   4.8   2.6
 34000 -48.1 -54.6  260  17  9   5.3   2.9 | -47.9 -54.2  275  21 11   6.8   3.7
 32000 -44.9 -48.8  255  19 10   5.3   2.9 | -43.8 -46.8  275  22 11   6.8   3.7
 30000 -40.9 -41.6  245  20 10   8.3   4.6 | -39.1 -38.4  270  21 11   7.2   3.9
 29000 -37.8 -36.0  240  20 11   8.3   4.5 | -36.9 -34.4  260  21 11   7.2   3.9
 28000 -35.3 -31.5  240  21 11   8.3   4.5 | -34.8 -30.6  255  21 11   7.1   3.9
 27000 -32.7 -26.9  240  21 11   8.9   4.9 | -32.4 -26.3  250  21 11   8.6   4.7
 26000 -30.1 -22.2  235  21 11   9.0   4.9 | -29.8 -21.6  250  21 11   8.6   4.7
 25000 -27.4 -17.3  235  20 10   8.9   4.9 | -27.2 -17.0  245  20 10   8.6   4.7
 24000 -24.7 -12.5  235  20 11   8.8   4.8 | -24.7 -12.5  245  20 10   8.2   4.5
 23000 -22.1  -7.8  235  21 11   8.8   4.8 | -22.3  -8.1  245  21 11   8.2   4.5
 22000 -19.4  -2.9  235  21 11   8.8   4.8 | -19.8  -3.6  245  21 11   8.2   4.5
 21000 -17.3   0.9  235  22 11   5.9   3.2 | -17.6   0.3  245  22 11   6.8   3.7
 20000 -15.6   3.9  230  23 12   5.8   3.2 | -15.6   3.9  245  23 12   6.7   3.7
 19500 -14.7   5.5  230  23 12   5.8   3.2 | -14.6   5.7  245  23 12   6.7   3.7
 19000 -13.8   7.2  230  24 12   5.7   3.1 | -13.6   7.5  245  24 12   6.4   3.5
 18500 -13.1   8.4  230  23 12   5.4   2.9 | -12.8   9.0  240  22 11   5.7   3.2
 18000 -12.3   9.9  225  23 12   5.4   3.0 | -12.0  10.4  235  20 11   5.9   3.2
 17500 -11.4  11.5  225  22 11   7.5   4.1 | -11.0  12.2  230  19 10   8.4   4.6
 17000 -10.3  13.5  220  20 10   7.8   4.3 |  -9.8  14.4  225  18  9   8.5   4.7
 16500  -9.2  15.4  215  19 10   8.2   4.5 |  -8.6  16.5  220  16  8   8.9   4.9
 16000  -7.9  17.8  215  18  9   8.6   4.7 |  -7.2  19.0  220  16  8   9.2   5.1
 15500  -6.6  20.1  210  18  9   8.6   4.7 |  -5.8  21.6  220  15  8   9.2   5.1
 15000  -5.4  22.3  210  17  9   8.7   4.8 |  -4.4  24.1  215  14  7   9.3   5.1
 14500  -4.1  24.6  205  16  8   8.7   4.8 |  -3.1  26.4  215  14  7   9.3   5.1
 14000  -2.1  28.2  200  15  8   8.6   4.7 |  -1.0  30.2  215  13  7   8.8   4.8
 13500  -0.8  30.6  200  14  7   8.6   4.7 |   0.3  32.5  215  12  6   8.7   4.8
 13000   0.4  32.7  200  13  7   8.3   4.5 |   1.6  34.9  210  12  6   8.6   4.7
 12500   1.7  35.1  195  12  6   8.3   4.6 |   2.9  37.2  210  11  6   8.6   4.7
 12000   2.9  37.2  195  10  5   8.5   4.7 |   4.1  39.4  205  10  5   8.5   4.7
 11500   4.2  39.6  195   9  5   8.5   4.7 |   5.4  41.7  205  10  5   8.6   4.7
 11000   5.5  41.9  195   8  4   8.3   4.5 |   6.5  43.7  205   9  5   6.5   3.6
 10500   6.8  44.2  200   6  3   4.0   2.2 |   7.5  45.5  205   8  4   9.8   5.4
 10250   6.9  44.4  200   6  3   5.4   3.0 |   8.4  47.1  205   7  4  10.8   5.9
 10000   7.7  45.9  200   6  3  12.3   6.8 |   9.0  48.2  210   7  3   7.3   4.0
  9750   8.5  47.3  205   6  3  10.5   5.7 |   9.6  49.3  210   6  3   8.3   4.6
  9500   9.4  48.9  205   5  3  11.0   6.1 |  10.2  50.4  215   5  3   7.8   4.3
  9250  10.2  50.4  210   5  3  10.6   5.8 |  10.8  51.4  220   5  2   7.0   3.8
  9000  10.9  51.6  210   5  3   9.9   5.4 |  11.3  52.3  230   4  2   7.2   3.9
  8750  11.6  52.9  210   5  3   9.6   5.2 |  11.9  53.4  240   4  2   7.5   4.1
  8500  12.4  54.3  210   5  3  10.0   5.5 |  12.4  54.3  255   4  2   8.0   4.4
  8250  13.2  55.8  215   5  3  10.9   6.0 |  13.1  55.6  260   4  2   9.6   5.3
  8000  14.0  57.2  215   5  3  10.3   5.6 |  13.8  56.8  260   4  2  10.1   5.6
  7750  14.7  58.5  215   5  3   9.4   5.2 |  14.6  58.3  260   5  2  10.0   5.5
  7500  15.4  59.7  220   5  3  10.0   5.5 |  15.3  59.5  265   5  2  10.1   5.5
  7250  16.2  61.2  220   5  3  10.6   5.8 |  16.1  61.0  265   5  2  10.4   5.7
  7000  17.0  62.6  220   5  3  10.1   5.6 |  16.9  62.4  265   5  3   9.8   5.4
  6750  17.7  63.9  225   5  3   9.8   5.4 |  17.6  63.7  265   5  3   9.0   4.9
  6500  18.5  65.3  225   5  3  10.7   5.9 |  18.3  64.9  265   5  3  10.4   5.7
  6250  19.3  66.7  225   5  3  11.7   6.4 |  19.1  66.4  265   5  3  11.7   6.4
  6000  20.1  68.2  225   5  2  10.1   5.6 |  20.0  68.0  265   5  3  10.4   5.7
  5750  20.9  69.6  230   5  2  12.6   6.9 |  20.7  69.3  265   5  3   9.9   5.4
  5500  22.1  71.8  230   5  2  17.5   9.6 |  21.5  70.7  265   5  3  11.2   6.2
  5250  23.4  74.1  235   5  2  16.1   8.8 |  22.3  72.1  270   5  3  11.4   6.3
  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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