Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 271245
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0645 MDT Tuesday, June 27, 2017

This forecast is for Tuesday, June 27, 2017:

If the trigger temperature of 87.0 F/30.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1716 ft/min (8.7 m/s)
   Maximum height of thermals.................. 22398 ft MSL (17559 ft AGL)

Forecast maximum temperature................... 98.0 F/37.1 C
Time of trigger temperature.................... 1030 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................. 15227 ft MSL (10388 ft AGL)
Thermal soaring outlook for Wednesday 06/28.... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:50:25 / 20:44:07 MDT
Total possible sunshine........... 14 hr 53 min 42 sec (893 min 42 sec)
Altitude of sun at 13:17:20 MDT... 74.14 degrees

Upper air data from rawinsonde observation taken on 06/27/2017 at 0600 MDT

Freezing level.................. 16051 ft MSL (11212 ft AGL)
Convective condensation level... 19925 ft MSL (15086 ft AGL)
Lifted condensation level....... 20991 ft MSL (16152 ft AGL)
Lifted index.................... -0.1
K index......................... +8.3

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  -64.3 -83.7   305   37   19   6.1   3.4   87.5 189.5    29.4      M    M
 45000  -59.3 -74.7   295   50   26   7.3   4.0   70.3 158.5    20.9      M    M
 40000  -52.0 -61.6   285   48   24   4.6   2.5   58.8 137.9    14.8      M    M
 38000  -50.4 -58.7   290   46   24   5.6   3.1   52.5 126.5    10.9      M    M
 36000  -46.6 -51.9   295   44   23   8.0   4.4   49.5 121.2     9.0      M    M
 34000  -41.8 -43.2   295   44   22   8.1   4.5   48.1 118.6     8.2      M    M
 32000  -36.7 -34.1   290   38   20   8.9   4.9   47.1 116.7     7.7      M    M
 30000  -31.9 -25.4   285   37   19   5.2   2.8   44.8 112.6     6.2      M    M
 29000  -29.6 -21.3   280   33   17   8.0   4.4   43.9 111.0     5.5      M    M
 28000  -27.3 -17.1   275   30   15   8.0   4.4   43.3 109.9     5.1      M    M
 27000  -24.9 -12.8   280   27   14   8.0   4.4   42.5 108.5     4.6      M    M
 26000  -22.5  -8.5   285   25   13   8.2   4.5   41.9 107.4     4.2      M    M
 25000  -20.6  -5.1   280   30   15   5.7   3.1   40.6 105.0     3.1      M    M
 24000  -18.6  -1.5   270   27   14   9.2   5.1   39.4 102.9     2.2      M    M
 23000  -15.9   3.4   260   27   14   8.7   4.8   39.1 102.5     2.0      M    M
 22000  -16.1   3.0   245   25   13   7.2   3.9   35.6  96.2    -1.1   1704  8.7
 21000  -13.9   7.0   225   26   13   8.4   4.6   35.0  94.9    -1.8   1608  8.2
 20000  -11.3  11.7   225   27   14   9.0   4.9   34.6  94.4    -2.1   1501  7.6
 19500  -10.0  14.0   230   28   14   8.7   4.8   34.5  94.1    -2.2   1446  7.3
 19000   -8.5  16.7   230   27   14  10.3   5.6   34.5  94.2    -2.3   1388  7.1
 18500   -7.1  19.2   230   26   13   9.3   5.1   34.5  94.0    -2.3   1332  6.8
 18000   -5.8  21.6   225   24   13   9.2   5.0   34.4  93.9    -2.4   1276  6.5
 17500   -4.4  24.1   230   24   12   9.2   5.0   34.3  93.7    -2.5   1220  6.2
 17000   -3.0  26.6   235   23   12   9.2   5.0   34.2  93.5    -2.6   1164  5.9
 16500   -0.9  30.4   240   23   12   9.2   5.0   34.1  93.3    -2.7   1080  5.5
 16000    0.4  32.7   245   23   12   9.2   5.0   34.0  93.2    -2.8   1024  5.2
 15500    1.8  35.2   250   23   12   9.2   5.0   33.8  92.9    -3.0    968  4.9
 15000    3.2  37.8   250   22   12   9.2   5.0   33.7  92.7    -3.1    912  4.6
 14500    4.6  40.3   255   22   11   9.2   5.0   33.6  92.5    -3.2    856  4.3
 14000    5.9  42.6   255   22   11   9.2   5.1   33.5  92.4    -3.3    800  4.1
 13500    7.3  45.1   260   23   12   9.2   5.1   33.5  92.2    -3.4    744  3.8
 13000    8.7  47.7   265   24   12   9.2   5.1   33.4  92.1    -3.4    688  3.5
 12500   10.1  50.2   265   25   13   9.2   5.1   33.3  91.9    -3.6    632  3.2
 12000   11.4  52.5   265   26   13   9.2   5.1   33.2  91.8    -3.7    576  2.9
 11500   12.8  55.0   260   26   14   9.3   5.1   33.1  91.6    -3.8    520  2.6
 11000   14.1  57.4   260   27   14   7.6   4.1   32.9  91.3    -4.0    466  2.4
 10500   15.2  59.4   255   27   14   7.3   4.0   32.5  90.5    -4.3    418  2.1
 10250   15.8  60.4   255   27   14   7.1   3.9   32.3  90.2    -4.5    395  2.0
 10000   16.3  61.3   255   27   14   7.0   3.8   32.1  89.8    -4.8    372  1.9
  9750   16.8  62.2   255   25   13   7.0   3.9   31.9  89.4    -5.0    349  1.8
  9500   17.3  63.1   255   24   12   7.0   3.9   31.7  89.0    -5.2    327  1.7
  9250   17.8  64.0   250   23   12   7.0   3.9   31.5  88.7    -5.5    304  1.5
  9000   18.3  64.9   250   21   11   7.0   3.9   31.3  88.3    -5.7    281  1.4
  8750   18.8  65.8   250   19   10   7.1   3.9   31.1  87.9    -5.9    259  1.3
  8500   19.3  66.7   250   17    9   6.9   3.8   30.8  87.5    -6.2    236  1.2
  8250   19.8  67.6   245   15    8   7.7   4.2   30.6  87.1    -6.4    213  1.1
  8000   20.5  68.9   245   13    7   9.0   5.0   30.5  87.0    -6.5    187  1.0
  7750   21.1  70.0   245   11    6   9.2   5.1   30.5  86.9    -6.6    160  0.8
  7500   21.8  71.2   240    9    5   9.2   5.0   30.5  86.8    -6.7    132  0.7
  7250   22.5  72.5   235    7    4   9.2   5.1   30.4  86.8    -6.7    105  0.5
  7000   23.2  73.8   225    5    3   9.2   5.1   30.4  86.7    -6.8     77  0.4
  6750   23.8  74.8   200    5    3   9.1   5.0   30.3  86.6    -6.9     50  0.3
  6500   24.5  76.1   170    6    3   9.5   5.2   30.3  86.5    -6.9     22  0.1
  6250   25.2  77.4   155    8    4   8.1   4.5   30.3  86.5    -7.0      M    M
  6000   25.6  78.1   145   10    5   5.2   2.8   30.0  86.0    -7.3      M    M
  5750   26.0  78.8   140   10    5   5.9   3.3   29.7  85.4    -7.7      M    M
  5500   26.3  79.3   125    8    4   1.7   0.9   29.3  84.8    -8.1      M    M
  5250   26.2  79.2   110    7    4  -1.4  -0.7   28.5  83.3    -8.9      M    M
  5000   26.0  78.8   090    7    3  -9.1  -5.0   27.5  81.6    -9.9      M    M

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

           06/27/2017 at 0900 MDT          |       06/27/2017 at 1200 MDT
                                           |
K index... +4.4  LI... +2.6                | K index... +3.0  LI... +3.7
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 -63.2 -81.8  290  32 16   2.0   1.1 | -63.1 -81.6  280  31 16   2.5   1.4
 45000 -58.9 -74.0  285  49 25   4.6   2.5 | -58.2 -72.8  285  52 27   4.8   2.6
 40000 -51.9 -61.4  290  57 29   4.7   2.6 | -51.1 -60.0  290  62 32   3.9   2.1
 38000 -49.1 -56.4  290  52 27   4.7   2.6 | -48.8 -55.8  290  57 29   3.9   2.1
 36000 -46.3 -51.3  295  48 25   4.6   2.5 | -46.4 -51.5  290  52 27   3.9   2.1
 34000 -41.6 -42.9  295  44 23   8.6   4.7 | -41.9 -43.4  285  49 25   8.5   4.6
 32000 -36.5 -33.7  290  40 21   8.5   4.7 | -36.8 -34.2  285  46 24   8.5   4.6
 30000 -31.1 -24.0  290  36 18   7.8   4.3 | -31.1 -24.0  285  41 21   8.4   4.6
 29000 -28.8 -19.8  285  34 17   7.8   4.3 | -28.6 -19.5  285  38 20   8.4   4.6
 28000 -26.4 -15.5  285  32 17   7.6   4.2 | -26.1 -15.0  285  36 18   7.4   4.1
 27000 -24.2 -11.6  285  32 16   7.6   4.2 | -24.1 -11.4  280  35 18   6.8   3.7
 26000 -21.9  -7.4  280  32 16   7.6   4.2 | -22.0  -7.6  275  35 18   6.8   3.7
 25000 -19.6  -3.3  280  32 16   7.6   4.1 | -20.0  -4.0  270  34 18   6.8   3.7
 24000 -17.6   0.3  270  30 15   6.3   3.5 | -18.0  -0.4  265  33 17   6.4   3.5
 23000 -15.7   3.7  265  27 14   6.4   3.5 | -16.1   3.0  265  33 17   6.4   3.5
 22000 -13.8   7.2  255  25 13   6.3   3.5 | -14.2   6.4  260  32 16   6.4   3.5
 21000 -12.0  10.4  245  25 13   6.1   3.3 | -12.1  10.2  260  32 16   7.1   3.9
 20000 -10.2  13.6  235  25 13   6.2   3.4 | -10.0  14.0  255  32 16   7.2   3.9
 19500  -9.3  15.3  230  25 13   6.3   3.4 |  -8.9  16.0  255  32 16   7.2   4.0
 19000  -8.4  16.9  225  26 14   6.5   3.5 |  -7.9  17.8  255  32 16   7.1   3.9
 18500  -7.5  18.5  225  28 15   6.6   3.6 |  -6.8  19.8  255  31 16   7.0   3.9
 18000  -6.6  20.1  220  30 15   7.1   3.9 |  -5.8  21.6  255  30 16   7.0   3.9
 17500  -5.4  22.3  220  32 16   8.3   4.5 |  -4.7  23.5  255  30 15   6.9   3.8
 17000  -4.2  24.4  225  33 17   8.2   4.5 |  -3.7  25.3  255  29 15   6.9   3.8
 16500  -3.0  26.6  225  34 17   9.3   5.1 |  -2.7  27.1  250  29 15   7.5   4.1
 16000  -1.6  29.1  225  34 18   9.3   5.1 |  -1.6  29.1  250  28 15   7.6   4.2
 15500  -0.2  31.6  225  35 18   9.3   5.1 |  -0.5  31.1  250  28 14   8.1   4.5
 15000   1.1  34.0  225  35 18   9.2   5.0 |   1.4  34.5  250  28 14   8.7   4.8
 14500   3.2  37.8  230  36 18   8.8   4.8 |   2.7  36.9  245  27 14   8.8   4.8
 14000   4.5  40.1  230  36 19   8.7   4.8 |   4.0  39.2  245  27 14   8.8   4.8
 13500   5.8  42.4  230  36 19   8.8   4.8 |   5.3  41.5  245  26 13   9.0   5.0
 13000   7.2  45.0  230  35 18   8.9   4.9 |   6.7  44.1  240  25 13   9.3   5.1
 12500   8.5  47.3  230  33 17   8.7   4.8 |   8.1  46.6  240  23 12   9.3   5.1
 12000   9.8  49.6  230  30 15   8.2   4.5 |   9.5  49.1  240  22 12   9.2   5.0
 11500  11.1  52.0  230  26 14   8.3   4.5 |  10.8  51.4  240  21 11   8.8   4.8
 11000  12.4  54.3  230  24 12   8.1   4.5 |  12.0  53.6  240  20 10   7.4   4.1
 10500  13.7  56.7  235  21 11   5.3   2.9 |  13.1  55.6  240  18  9  10.1   5.5
 10250  13.9  57.0  235  21 11   5.8   3.2 |  14.0  57.2  240  17  9  11.1   6.1
 10000  14.6  58.3  235  20 10  10.0   5.5 |  14.6  58.3  240  16  8   8.4   4.6
  9750  15.3  59.5  240  19 10   9.2   5.1 |  15.3  59.5  240  15  8   9.0   4.9
  9500  16.0  60.8  240  18  9   8.2   4.5 |  16.0  60.8  245  14  7   9.4   5.2
  9250  16.6  61.9  240  17  9   6.7   3.7 |  16.7  62.1  245  13  7  10.1   5.5
  9000  17.1  62.8  240  16  8   7.5   4.1 |  17.4  63.3  245  13  7   9.9   5.4
  8750  17.7  63.9  240  15  8   7.8   4.3 |  18.2  64.8  245  13  7   9.7   5.3
  8500  18.2  64.8  235  14  7   7.4   4.0 |  18.9  66.0  245  12  6  10.3   5.6
  8250  18.7  65.7  235  13  7   6.8   3.7 |  19.7  67.5  245  12  6  10.9   6.0
  8000  19.2  66.6  235  12  6   6.2   3.4 |  20.5  68.9  245  12  6  10.2   5.6
  7750  19.7  67.5  230  11  5   6.4   3.5 |  21.3  70.3  245  12  6   9.7   5.3
  7500  20.1  68.2  230  10  5   4.7   2.6 |  22.0  71.6  245  12  6   9.8   5.4
  7250  20.3  68.5  220   9  5   3.1   1.7 |  22.7  72.9  250  12  6   9.7   5.3
  7000  20.5  68.9  210   9  4   2.9   1.6 |  23.5  74.3  250  12  6   9.8   5.4
  6750  20.6  69.1  200   8  4   3.0   1.7 |  24.2  75.6  250  12  6  10.0   5.5
  6500  20.9  69.6  195   8  4   7.7   4.2 |  25.0  77.0  250  11  6  10.8   5.9
  6250  21.5  70.7  190   8  4  10.8   5.9 |  25.8  78.4  250  11  6  11.7   6.4
  6000  22.2  72.0  185   8  4   8.7   4.8 |  26.7  80.1  250  11  6  10.4   5.7
  5750  22.8  73.0  185   7  4   9.2   5.1 |  27.5  81.5  250  10  5  12.6   6.9
  5500  23.6  74.5  185   7  4  11.9   6.5 |  28.6  83.5  250  10  5  17.6   9.7
  5250  24.5  76.1  185   7  3  11.4   6.3 |  30.0  86.0  250  11  6  17.9   9.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/27/2017 at 1500 MDT          |       06/27/2017 at 1800 MDT
                                           |
K index... +7.9  LI... +0.5                | K index... +11.7  LI... +0.9
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 -63.7 -82.7  280  37 19   2.9   1.6 | -63.0 -81.4  290  37 19   2.7   1.5
 45000 -58.4 -73.1  285  56 29   4.6   2.5 | -58.1 -72.6  295  60 31   4.2   2.3
 40000 -51.5 -60.7  290  67 34   4.3   2.3 | -51.7 -61.1  295  72 37   4.5   2.4
 38000 -49.0 -56.2  290  63 32   4.3   2.3 | -49.0 -56.2  295  68 35   4.5   2.4
 36000 -46.4 -51.5  290  59 30   4.2   2.3 | -46.3 -51.3  290  63 33   4.5   2.4
 34000 -41.9 -43.4  285  56 29   8.4   4.6 | -41.9 -43.4  290  58 30   8.1   4.5
 32000 -36.9 -34.4  285  53 27   8.4   4.6 | -37.1 -34.8  290  53 27   8.1   4.5
 30000 -31.4 -24.5  280  48 25   8.0   4.4 | -32.4 -26.3  285  48 25   7.6   4.2
 29000 -29.0 -20.2  280  45 23   8.0   4.4 | -29.5 -21.1  285  46 23   7.6   4.2
 28000 -26.6 -15.9  280  43 22   7.6   4.2 | -27.3 -17.1  280  43 22   7.3   4.0
 27000 -24.4 -11.9  275  41 21   7.3   4.0 | -25.1 -13.2  280  41 21   7.1   3.9
 26000 -22.2  -8.0  275  38 20   7.3   4.0 | -23.0  -9.4  275  39 20   7.1   3.9
 25000 -20.0  -4.0  270  36 19   7.3   4.0 | -20.9  -5.6  275  36 19   7.1   3.9
 24000 -17.9  -0.2  270  34 17   6.8   3.7 | -19.0  -2.2  275  33 17   6.2   3.4
 23000 -15.9   3.4  270  32 16   6.8   3.7 | -17.2   1.0  275  29 15   6.2   3.4
 22000 -13.9   7.0  270  29 15   6.5   3.6 | -15.4   4.3  275  24 13   6.6   3.6
 21000 -12.3   9.9  275  26 14   4.9   2.7 | -13.0   8.6  270  22 12   8.4   4.6
 20000 -10.9  12.4  275  23 12   5.1   2.8 | -10.6  12.9  270  21 11   8.4   4.6
 19500 -10.2  13.6  280  22 11   4.9   2.7 |  -9.4  15.1  265  20 10   8.4   4.6
 19000  -9.3  15.3  280  21 11   8.9   4.9 |  -8.1  17.4  265  20 10   8.9   4.9
 18500  -7.9  17.8  275  20 11   9.2   5.0 |  -6.8  19.8  260  19 10   8.9   4.9
 18000  -6.5  20.3  270  20 11   9.2   5.0 |  -5.5  22.1  260  19 10   9.0   4.9
 17500  -5.1  22.8  270  20 10   9.2   5.1 |  -4.1  24.6  260  19 10   9.3   5.1
 17000  -3.8  25.2  265  19 10   9.2   5.0 |  -2.7  27.1  260  19 10   9.3   5.1
 16500  -2.4  27.7  265  18  9   9.4   5.2 |  -1.4  29.5  260  18  9   9.0   5.0
 16000  -1.0  30.2  265  18  9   9.4   5.2 |  -0.0  32.0  265  18  9   9.0   5.0
 15500   0.4  32.7  265  17  9   9.6   5.2 |   1.3  34.3  265  18  9   9.2   5.0
 15000   1.8  35.2  265  17  9   9.7   5.3 |   2.7  36.9  260  18  9   9.3   5.1
 14500   3.3  37.9  265  16  8   9.6   5.3 |   4.1  39.4  260  18  9   9.3   5.1
 14000   5.3  41.5  260  16  8   9.1   5.0 |   6.2  43.2  260  18  9   9.3   5.1
 13500   6.7  44.1  260  16  8   9.3   5.1 |   7.6  45.7  260  18  9   9.3   5.1
 13000   8.1  46.6  260  16  8   9.4   5.2 |   9.0  48.2  260  18  9   9.3   5.1
 12500   9.5  49.1  260  16  8   9.3   5.1 |  10.4  50.7  260  18  9   9.3   5.1
 12000  10.8  51.4  260  16  8   9.0   4.9 |  11.8  53.2  260  18  9   9.2   5.1
 11500  12.2  54.0  260  16  8   8.8   4.8 |  13.1  55.6  260  17  9   9.1   5.0
 11000  13.4  56.1  260  16  8   7.9   4.3 |  14.4  57.9  265  17  9   8.2   4.5
 10500  14.5  58.1  260  15  8  11.1   6.1 |  15.6  60.1  265  17  9  10.1   5.5
 10250  15.5  59.9  260  15  8  12.1   6.7 |  16.5  61.7  265  16  8  10.4   5.7
 10000  16.2  61.2  260  15  8   8.5   4.7 |  17.1  62.8  265  16  8   8.2   4.5
  9750  16.9  62.4  260  14  7   9.7   5.3 |  17.7  63.9  265  15  8   8.7   4.8
  9500  17.6  63.7  260  14  7   8.5   4.6 |  18.4  65.1  270  14  7   8.8   4.8
  9250  18.3  64.9  260  14  7   9.1   5.0 |  19.0  66.2  270  14  7   9.5   5.2
  9000  19.0  66.2  265  14  7  10.6   5.8 |  19.8  67.6  270  13  7   9.7   5.3
  8750  19.8  67.6  265  14  7  10.1   5.5 |  20.5  68.9  270  13  7   9.6   5.3
  8500  20.5  68.9  265  13  7  10.7   5.9 |  21.2  70.2  270  13  7   9.9   5.4
  8250  21.4  70.5  265  13  7  11.1   6.1 |  22.0  71.6  270  13  7  10.5   5.8
  8000  22.2  72.0  265  13  7   9.9   5.4 |  22.7  72.9  270  13  7   9.9   5.4
  7750  22.9  73.2  265  13  7   8.9   4.9 |  23.5  74.3  270  13  6   9.2   5.1
  7500  23.6  74.5  265  13  7   9.8   5.4 |  24.2  75.6  270  12  6   9.6   5.3
  7250  24.3  75.7  265  13  7  10.8   5.9 |  24.9  76.8  270  12  6  10.1   5.5
  7000  25.2  77.4  265  13  7  10.5   5.8 |  25.7  78.3  275  12  6  10.0   5.5
  6750  25.9  78.6  265  13  7  10.1   5.5 |  26.4  79.5  275  12  6   9.6   5.3
  6500  26.7  80.1  265  13  7  10.9   6.0 |  27.1  80.8  275  12  6  10.3   5.6
  6250  27.5  81.5  265  12  6  12.0   6.6 |  27.9  82.2  275  12  6  11.0   6.1
  6000  28.4  83.1  265  12  6  10.6   5.8 |  28.7  83.7  275  11  6  10.7   5.9
  5750  29.2  84.6  265  12  6  11.3   6.2 |  29.5  85.1  275  11  6  10.4   5.7
  5500  30.2  86.4  265  12  6  16.6   9.1 |  30.3  86.5  275  10  5  11.4   6.2
  5250  31.6  88.9  265  12  6  20.2  11.1 |  31.2  88.2  275  10  5  12.9   7.1
  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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