Soaring Guidance
Issued by NWS Grand Junction, CO

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681
UXUS97 KGJT 261228
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0628 MDT Saturday, May 26, 2018

This forecast is for Saturday, May 26, 2018:

If the trigger temperature of 81.1 F/27.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1457 ft/min (7.4 m/s)
   Maximum height of thermals.................. 20351 ft MSL (15512 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1045 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................. 14270 ft MSL (9431 ft AGL)
Thermal soaring outlook for Sunday 05/27....... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:53:07 / 20:29:08 MDT
Total possible sunshine........... 14 hr 36 min 1 sec (876 min 1 sec)
Altitude of sun at 13:11:19 MDT... 72.08 degrees

Upper air data from rawinsonde observation taken on 05/26/2018 at 0600 MDT

Freezing level.................. 15313 ft MSL (10474 ft AGL)
Convective condensation level... 22483 ft MSL (17644 ft AGL)
Lifted condensation level....... 22077 ft MSL (17238 ft AGL)
Lifted index.................... +1.0
K index......................... -4.2

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -58.9 -74.0   265   26   13   5.2   2.9   99.0 210.1    37.5      M    M
 45000  -61.4 -78.5   215   50   26  -4.3  -2.3   69.1 156.4    21.8      M    M
 40000  -57.3 -71.1   240   54   28  -0.8  -0.4   52.7 126.9    12.5      M    M
 38000  -55.7 -68.3   235   37   19   7.5   4.1   46.4 115.5     8.5      M    M
 36000  -50.6 -59.1   225   36   19   9.0   4.9   45.2 113.3     7.9      M    M
 34000  -45.3 -49.5   215   37   19   8.6   4.7   44.2 111.5     7.4      M    M
 32000  -40.2 -40.4   210   38   20   8.6   4.7   43.3 110.0     7.0      M    M
 30000  -34.3 -29.7   195   43   22   8.6   4.7   42.6 108.6     6.6      M    M
 29000  -31.8 -25.2   195   43   22   8.6   4.7   42.0 107.7     6.2      M    M
 28000  -29.2 -20.6   200   44   22   7.2   4.0   41.6 106.9     6.0      M    M
 27000  -27.3 -17.1   200   44   23   6.4   3.5   40.2 104.3     4.9      M    M
 26000  -25.4 -13.7   205   45   23   6.4   3.5   38.9 102.0     4.0      M    M
 25000  -23.5 -10.3   205   45   23   6.6   3.6   37.8 100.0     3.1      M    M
 24000  -21.3  -6.3   210   46   24   7.9   4.3   37.0  98.5     2.5      M    M
 23000  -18.9  -2.0   210   43   22   7.9   4.3   36.2  97.1     1.8      M    M
 22000  -16.6   2.1   215   40   21   7.9   4.3   35.5  95.9     1.3      M    M
 21000  -14.3   6.3   215   37   19   6.5   3.6   34.8  94.6     0.7      M    M
 20000  -12.4   9.7   195   25   13   6.7   3.6   33.7  92.6    -0.3   1432  7.3
 19500  -11.4  11.5   190   25   13   6.6   3.6   33.1  91.6    -0.7   1388  7.1
 19000  -10.3  13.5   190   26   13   8.7   4.8   32.7  90.8    -1.1   1341  6.8
 18500   -8.9  16.0   190   27   14   9.4   5.1   32.6  90.6    -1.2   1284  6.5
 18000   -7.5  18.5   195   28   14   9.4   5.2   32.5  90.5    -1.3   1227  6.2
 17500   -6.1  21.0   195   29   15   9.4   5.2   32.4  90.3    -1.4   1170  5.9
 17000   -3.9  25.0   200   30   16   9.5   5.2   32.4  90.2    -1.5   1084  5.5
 16500   -2.5  27.5   200   31   16   9.7   5.3   32.4  90.2    -1.5   1027  5.2
 16000   -1.3  29.7   200   33   17   7.2   3.9   32.2  89.9    -1.7    975  5.0
 15500   -0.2  31.6   205   35   18   7.2   4.0   31.8  89.2    -2.1    928  4.7
 15000    0.9  33.6   205   37   19   7.2   4.0   31.3  88.4    -2.5    881  4.5
 14500    1.9  35.4   200   35   18   7.2   3.9   30.9  87.7    -2.9    834  4.2
 14000    3.1  37.6   200   34   17   8.8   4.8   30.6  87.1    -3.2    784  4.0
 13500    4.4  39.9   195   34   17   8.6   4.7   30.5  86.8    -3.4    731  3.7
 13000    5.7  42.3   195   34   17   8.6   4.7   30.3  86.5    -3.5    677  3.4
 12500    7.0  44.6   205   32   17   8.5   4.7   30.1  86.1    -3.7    624  3.2
 12000    8.3  46.9   210   31   16   7.0   3.9   29.9  85.8    -3.9    571  2.9
 11500    8.9  48.0   215   28   14   4.2   2.3   29.1  84.4    -4.7    536  2.7
 11000    9.9  49.8   225   26   13   8.8   4.9   28.6  83.5    -5.3    492  2.5
 10500   11.1  52.0   230   24   12   8.9   4.9   28.4  83.1    -5.5    440  2.2
 10250   11.8  53.2   235   23   12   6.7   3.7   28.3  82.9    -5.6    414  2.1
 10000   12.2  54.0   240   18    9   7.1   3.9   28.0  82.3    -6.0    394  2.0
  9750   12.9  55.2   240   17    9   9.4   5.2   27.9  82.2    -6.0    366  1.9
  9500   13.5  56.3   235   17    9   8.8   4.8   27.8  82.1    -6.1    339  1.7
  9250   14.2  57.6   235   16    8   9.0   4.9   27.8  82.0    -6.2    312  1.6
  9000   14.8  58.6   230   16    8   8.9   4.9   27.7  81.9    -6.3    285  1.4
  8750   15.5  59.9   225   15    8   8.9   4.9   27.7  81.8    -6.4    258  1.3
  8500   16.2  61.2   220   14    7   8.9   4.9   27.6  81.7    -6.4    230  1.2
  8250   16.8  62.2   215   13    7   8.9   4.9   27.5  81.5    -6.5    203  1.0
  8000   17.5  63.5   205   12    6   8.9   4.9   27.5  81.4    -6.6    176  0.9
  7750   18.1  64.6   200   11    6   8.9   4.9   27.4  81.3    -6.7    149  0.8
  7500   18.8  65.8   195   10    5   9.0   4.9   27.3  81.2    -6.8    122  0.6
  7250   19.5  67.1   190    9    5   8.8   4.8   27.3  81.1    -6.9     94  0.5
  7000   20.1  68.2   180    8    4   9.4   5.2   27.2  80.9    -7.0     67  0.3
  6750   20.8  69.4   170   11    5   7.1   3.9   27.1  80.8    -7.1     40  0.2
  6500   21.2  70.2   165   14    7   4.6   2.5   26.8  80.2    -7.4     21  0.1
  6250   21.6  70.9   160   18    9   5.5   3.0   26.4  79.5    -7.8      2  0.0
  6000   21.9  71.4   155   22   11   4.0   2.2   26.1  78.9    -8.2      M    M
  5750   22.3  72.1   155   20   10   9.1   5.0   25.7  78.3    -8.5      M    M
  5500   22.7  72.9   150   17    9  -9.9  -5.4   25.4  77.7    -8.9      M    M
  5250   20.8  69.4   140   13    7 -28.5 -15.6   22.8  73.0   -11.5      M    M
  5000   19.2  66.6   130   10    5 -14.2  -7.8   20.4  68.8   -13.9     36  0.2

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

           05/26/2018 at 0900 MDT          |       05/26/2018 at 1200 MDT
                                           |
K index... -11.3  LI... +5.5               | K index... -7.2  LI... +5.7
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 -61.1 -78.0  225  33 17   2.1   1.2 | -60.6 -77.1  215  32 16   2.2   1.2
 45000 -58.3 -72.9  225  45 23   0.7   0.4 | -57.7 -71.9  220  52 27   0.6   0.3
 40000 -57.2 -71.0  235  46 24   3.2   1.8 | -56.8 -70.2  230  55 28   3.1   1.7
 38000 -54.1 -65.4  230  47 24   5.2   2.8 | -53.7 -64.7  225  60 31   5.3   2.9
 36000 -51.0 -59.8  220  48 25   5.1   2.8 | -50.5 -58.9  225  64 33   5.2   2.9
 34000 -46.6 -51.9  215  48 25   8.4   4.6 | -46.5 -51.7  220  61 31   7.8   4.3
 32000 -41.6 -42.9  210  46 24   8.4   4.6 | -41.8 -43.2  220  52 27   7.8   4.3
 30000 -36.5 -33.7  210  46 24   8.7   4.8 | -36.8 -34.2  215  48 25   8.8   4.8
 29000 -33.9 -29.0  210  46 24   8.7   4.8 | -34.1 -29.4  215  47 24   8.8   4.8
 28000 -31.3 -24.3  210  47 24   8.7   4.8 | -30.8 -23.4  210  46 24   8.8   4.8
 27000 -28.2 -18.8  210  47 24   8.0   4.4 | -28.3 -18.9  210  46 24   8.5   4.7
 26000 -25.8 -14.4  215  47 24   8.0   4.4 | -25.7 -14.3  210  46 23   8.5   4.7
 25000 -23.4 -10.1  215  47 24   8.0   4.4 | -23.2  -9.8  210  45 23   8.6   4.7
 24000 -21.0  -5.8  215  46 24   8.0   4.4 | -20.8  -5.4  210  46 23   7.5   4.1
 23000 -18.7  -1.7  215  45 23   8.0   4.4 | -18.6  -1.5  210  46 24   7.5   4.1
 22000 -16.3   2.7  215  43 22   8.1   4.4 | -16.4   2.5  210  47 24   7.5   4.1
 21000 -14.0   6.8  215  41 21   7.5   4.1 | -14.0   6.8  210  47 24   8.3   4.5
 20000 -11.8  10.8  215  39 20   7.5   4.1 | -11.5  11.3  210  47 24   8.3   4.5
 19500 -10.7  12.7  215  38 20   7.5   4.1 | -10.3  13.5  210  47 24   8.2   4.5
 19000  -9.5  14.9  215  37 19   7.6   4.2 |  -9.0  15.8  210  47 24   7.8   4.3
 18500  -8.4  16.9  215  37 19   7.7   4.2 |  -7.9  17.8  210  46 24   7.4   4.0
 18000  -7.2  19.0  215  37 19   7.7   4.2 |  -6.8  19.8  210  45 23   7.3   4.0
 17500  -6.1  21.0  215  36 19   7.8   4.3 |  -5.7  21.7  210  44 23   7.6   4.2
 17000  -4.9  23.2  215  36 19   7.8   4.3 |  -4.6  23.7  210  43 22   7.6   4.2
 16500  -3.8  25.2  215  36 18   7.9   4.3 |  -3.5  25.7  210  43 22   7.4   4.0
 16000  -2.6  27.3  215  35 18   7.9   4.3 |  -2.4  27.7  210  42 22   7.2   4.0
 15500  -1.4  29.5  215  35 18   7.7   4.2 |  -1.3  29.7  210  41 21   7.2   3.9
 15000  -0.3  31.5  215  34 17   6.8   3.8 |  -0.2  31.6  210  40 21   7.1   3.9
 14500   0.7  33.3  215  33 17   7.0   3.8 |   0.8  33.4  210  39 20   7.1   3.9
 14000   1.7  35.1  215  31 16   6.1   3.4 |   1.9  35.4  210  38 19   6.9   3.8
 13500   2.6  36.7  215  30 15   6.2   3.4 |   3.4  38.1  210  35 18   6.8   3.7
 13000   4.0  39.2  215  28 14   6.2   3.4 |   4.4  39.9  205  32 16   6.2   3.4
 12500   4.9  40.8  215  26 13   6.3   3.4 |   5.3  41.5  205  29 15   6.2   3.4
 12000   5.9  42.6  215  25 13   7.2   4.0 |   6.3  43.3  205  26 13   7.8   4.3
 11500   7.0  44.6  210  23 12   7.2   4.0 |   7.4  45.3  200  23 12   7.8   4.3
 11000   8.0  46.4  210  21 11   6.4   3.5 |   8.5  47.3  195  20 10   6.9   3.8
 10500   8.9  48.0  205  20 10   9.3   5.1 |   9.5  49.1  185  17  9   9.3   5.1
 10250   9.8  49.6  205  20 10  10.0   5.5 |  10.3  50.5  185  16  8  10.3   5.6
 10000  10.3  50.5  200  19 10   6.6   3.6 |  11.0  51.8  180  16  8   7.9   4.3
  9750  10.8  51.4  200  18  9   7.6   4.2 |  11.6  52.9  180  15  8   8.5   4.7
  9500  11.4  52.5  200  17  9   7.0   3.8 |  12.2  54.0  175  14  7   8.4   4.6
  9250  11.9  53.4  195  16  8   6.1   3.3 |  12.8  55.0  175  13  7   9.6   5.2
  9000  12.3  54.1  195  16  8   7.1   3.9 |  13.6  56.5  175  13  7  10.0   5.5
  8750  12.9  55.2  195  15  8   8.3   4.6 |  14.3  57.7  175  13  7   9.5   5.2
  8500  13.5  56.3  190  14  7   7.8   4.3 |  15.0  59.0  175  13  6   9.7   5.3
  8250  14.1  57.4  190  14  7   7.7   4.2 |  15.8  60.4  175  12  6  10.1   5.6
  8000  14.6  58.3  190  14  7   6.5   3.6 |  16.5  61.7  175  12  6  10.0   5.5
  7750  15.1  59.2  185  14  7   6.1   3.4 |  17.3  63.1  175  12  6   9.5   5.2
  7500  15.5  59.9  180  14  7   4.9   2.7 |  18.0  64.4  175  12  6   9.9   5.4
  7250  15.8  60.4  175  14  7   3.2   1.8 |  18.7  65.7  175  12  6  10.5   5.8
  7000  16.0  60.8  170  13  7   2.5   1.3 |  19.5  67.1  175  12  6  10.5   5.7
  6750  16.1  61.0  165  13  7   0.9   0.5 |  20.3  68.5  175  11  6   9.9   5.4
  6500  16.3  61.3  160  12  6   5.9   3.2 |  21.0  69.8  175  11  6  10.8   5.9
  6250  16.9  62.4  155  11  6  10.0   5.5 |  21.9  71.4  175  11  6  11.7   6.4
  6000  17.6  63.7  155  10  5   8.8   4.8 |  22.8  73.0  175  11  6  11.3   6.2
  5750  18.3  64.9  155   9  5   9.9   5.4 |  23.6  74.5  175  10  5  12.4   6.8
  5500  19.1  66.4  155   9  4  11.2   6.2 |  24.7  76.5  175  10  5  15.7   8.6
  5250  19.9  67.8  150   8  4  11.3   6.2 |  25.9  78.6  175  10  5  18.2  10.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/26/2018 at 1500 MDT          |       05/26/2018 at 1800 MDT
                                           |
K index... +1.3  LI... +1.6                | K index... +8.9  LI... +0.4
CAPE... 0.0  CIN... 0.0                    | CAPE... +0.2  CIN... -0.2
                                           |
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 -60.7 -77.3  220  34 17   1.2   0.7 | -58.4 -73.1  225  32 16   3.2   1.8
 45000 -59.0 -74.2  220  57 29   0.7   0.4 | -54.9 -66.8  230  51 26  -2.9  -1.6
 40000 -57.9 -72.2  225  76 39   3.9   2.2 | -59.4 -74.9  220  76 39   0.9   0.5
 38000 -53.5 -64.3  220  76 39   7.3   4.0 | -54.4 -65.9  210  70 36   8.6   4.7
 36000 -49.2 -56.6  220  77 39   7.3   4.0 | -49.3 -56.7  205  63 33   8.6   4.7
 34000 -45.1 -49.2  215  70 36   6.5   3.6 | -44.8 -48.6  200  61 31   6.4   3.5
 32000 -41.2 -42.2  210  60 31   6.5   3.6 | -41.0 -41.8  200  60 31   6.4   3.5
 30000 -36.7 -34.1  210  55 28   8.3   4.5 | -37.0 -34.6  200  58 30   6.7   3.7
 29000 -34.2 -29.6  210  55 28   8.3   4.5 | -35.0 -31.0  200  57 29   6.7   3.7
 28000 -31.2 -24.2  210  55 28   8.3   4.6 | -33.0 -27.4  200  56 29   6.8   3.7
 27000 -28.8 -19.8  205  54 28   7.7   4.2 | -30.2 -22.4  200  54 28   7.8   4.3
 26000 -26.5 -15.7  205  53 27   7.7   4.2 | -27.9 -18.2  200  53 27   7.8   4.3
 25000 -24.2 -11.6  205  52 27   7.7   4.2 | -25.6 -14.1  200  52 27   7.8   4.3
 24000 -21.9  -7.4  205  51 26   7.8   4.3 | -23.3  -9.9  200  51 26   7.8   4.3
 23000 -19.5  -3.1  205  50 26   7.9   4.3 | -21.0  -5.8  205  49 25   7.8   4.3
 22000 -17.2   1.0  205  49 25   7.9   4.3 | -18.6  -1.5  205  47 24   7.8   4.3
 21000 -15.0   5.0  205  48 25   7.4   4.0 | -16.2   2.8  205  45 23   8.5   4.7
 20000 -12.8   9.0  200  47 24   7.4   4.1 | -13.6   7.5  200  44 22   8.6   4.7
 19500 -11.7  10.9  200  47 24   7.4   4.1 | -12.4   9.7  200  43 22   8.6   4.7
 19000 -10.6  12.9  200  46 24   7.8   4.3 | -11.1  12.0  200  42 22   8.8   4.8
 18500  -9.4  15.1  200  46 24   8.3   4.6 |  -9.8  14.4  200  41 21   9.1   5.0
 18000  -8.1  17.4  200  46 24   8.3   4.6 |  -8.4  16.9  195  40 20   9.1   5.0
 17500  -6.9  19.6  200  46 24   8.6   4.7 |  -7.0  19.4  195  38 20   9.2   5.0
 17000  -5.6  21.9  200  45 23   8.6   4.7 |  -5.7  21.7  195  37 19   9.2   5.0
 16500  -4.3  24.3  200  44 23   8.4   4.6 |  -4.3  24.3  195  36 18   9.2   5.1
 16000  -3.1  26.4  200  42 22   8.2   4.5 |  -3.0  26.6  195  34 18   9.3   5.1
 15500  -1.9  28.6  200  40 21   8.2   4.5 |  -1.6  29.1  190  33 17   9.3   5.1
 15000  -0.6  30.9  200  38 20   8.9   4.9 |  -0.2  31.6  190  31 16   9.5   5.2
 14500   0.7  33.3  200  35 18   8.8   4.9 |   1.2  34.2  190  31 16   9.5   5.2
 14000   2.0  35.6  200  32 17   9.1   5.0 |   2.6  36.7  190  30 15   9.5   5.2
 13500   4.1  39.4  195  28 15   9.1   5.0 |   4.0  39.2  190  29 15   9.5   5.2
 13000   5.4  41.7  195  26 13   9.0   4.9 |   6.2  43.2  190  29 15   9.7   5.3
 12500   6.8  44.2  195  24 12   9.0   4.9 |   7.6  45.7  190  28 14   9.7   5.3
 12000   8.2  46.8  195  22 11  10.0   5.5 |   9.1  48.4  190  27 14   9.7   5.3
 11500   9.6  49.3  195  21 11  10.1   5.5 |  10.5  50.9  195  26 14   9.8   5.4
 11000  11.0  51.8  190  20 10   8.6   4.7 |  11.9  53.4  195  26 13   8.7   4.8
 10500  12.3  54.1  190  19 10  10.6   5.8 |  13.2  55.8  195  25 13  10.1   5.6
 10250  13.2  55.8  190  19 10  11.7   6.4 |  14.0  57.2  195  25 13  11.2   6.2
 10000  14.0  57.2  190  19 10   9.6   5.2 |  14.8  58.6  195  24 13   9.6   5.3
  9750  14.7  58.5  190  19 10   9.8   5.4 |  15.5  59.9  195  24 12   9.5   5.2
  9500  15.4  59.7  190  19 10   9.7   5.3 |  16.2  61.2  195  24 12   9.6   5.2
  9250  16.2  61.2  190  19 10  10.2   5.6 |  16.9  62.4  195  23 12  10.0   5.5
  9000  16.9  62.4  190  18 10  10.1   5.5 |  17.7  63.9  195  23 12   9.7   5.3
  8750  17.7  63.9  190  18  9   9.7   5.3 |  18.4  65.1  195  23 12   9.5   5.2
  8500  18.4  65.1  190  18  9   9.6   5.3 |  19.1  66.4  195  23 12   8.8   4.8
  8250  19.1  66.4  190  18  9  11.4   6.3 |  19.8  67.6  195  22 11  11.8   6.5
  8000  20.1  68.2  190  18  9  10.9   6.0 |  20.7  69.3  195  22 11  11.5   6.3
  7750  20.8  69.4  190  18  9   8.8   4.8 |  21.4  70.5  195  22 11   8.2   4.5
  7500  21.4  70.5  190  17  9   9.5   5.2 |  22.1  71.8  195  21 11   9.0   4.9
  7250  22.2  72.0  190  17  9  10.5   5.8 |  22.8  73.0  195  21 11   9.6   5.3
  7000  23.0  73.4  190  17  9  10.6   5.8 |  23.5  74.3  195  21 11  10.2   5.6
  6750  23.7  74.7  190  17  9   9.5   5.2 |  24.3  75.7  195  20 10   9.8   5.4
  6500  24.5  76.1  190  16  8  10.3   5.6 |  25.0  77.0  195  20 10  10.0   5.5
  6250  25.3  77.5  190  16  8  11.3   6.2 |  25.7  78.3  195  19 10  10.1   5.5
  6000  26.1  79.0  190  16  8  11.7   6.4 |  26.5  79.7  195  18  9  10.2   5.6
  5750  27.0  80.6  190  15  8  10.9   6.0 |  27.3  81.1  195  17  9  10.9   6.0
  5500  27.9  82.2  190  14  7  14.4   7.9 |  28.1  82.6  195  15  8   9.6   5.3
  5250  29.2  84.6  190  14  7  22.2  12.2 |  28.6  83.5  195  14  7   5.9   3.3
  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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