Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 031247
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0647 MDT Wednesday, June 3, 2015

This forecast is for Wednesday, June 3, 2015:

If the trigger temperature of 81.8 F/27.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1424 ft/min (7.2 m/s)
   Maximum height of thermals.................. 19464 ft MSL (14625 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1300 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................. 11646 ft MSL (6807 ft AGL)
Thermal soaring outlook for Thursday 06/04..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:49:34 / 20:34:50 MDT
Total possible sunshine........... 14 hr 45 min 16 sec (885 min 16 sec)
Altitude of sun at 13:12:23 MDT... 73.20 degrees

Upper air data from rawinsonde observation taken on 06/03/2015 at 0600 MDT

Freezing level.................. 14492 ft MSL (9653 ft AGL)
Convective condensation level... 20775 ft MSL (15936 ft AGL)
Lifted condensation level....... 20305 ft MSL (15466 ft AGL)
Lifted index.................... +1.1
K index......................... +1.9

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  -59.9 -75.8   255   20   10   0.3   0.1   96.9 206.4    37.6      M    M
 45000  -57.3 -71.1   265   54   28  -0.8  -0.5   76.8 170.2    27.8      M    M
 40000  -58.0 -72.4   260   61   31   8.5   4.7   52.8 127.1    14.0      M    M
 38000  -56.0 -68.8   255   67   34   8.4   4.6   47.0 116.6    10.4      M    M
 36000  -51.1 -60.0   245   64   33   7.0   3.8   44.6 112.3     9.0      M    M
 34000  -45.8 -50.4   250   51   26   8.9   4.9   43.7 110.7     8.7      M    M
 32000  -40.5 -40.9   245   48   25   8.9   4.9   42.8 109.1     8.2      M    M
 30000  -35.4 -31.7   245   46   24   8.2   4.5   41.9 107.4     7.7      M    M
 29000  -33.5 -28.3   245   43   22   4.9   2.7   40.6 105.1     6.8      M    M
 28000  -31.5 -24.7   245   41   21   7.3   4.0   39.4 102.9     6.0      M    M
 27000  -29.5 -21.1   245   38   20   6.3   3.5   38.2 100.7     5.1      M    M
 26000  -27.6 -17.7   245   36   18   7.4   4.1   36.9  98.4     4.1      M    M
 25000  -24.8 -12.6   245   33   17   9.4   5.1   36.7  98.0     4.0      M    M
 24000  -22.0  -7.6   245   32   17   9.6   5.3   36.6  97.9     4.0      M    M
 23000  -19.7  -3.5   245   33   17   7.2   4.0   35.7  96.3     3.3      M    M
 22000  -17.5   0.5   240   33   17   7.2   4.0   34.8  94.7     2.6      M    M
 21000  -15.3   4.5   240   34   17   7.2   4.0   34.0  93.2     1.9      M    M
 20000  -13.2   8.2   225   27   14   6.6   3.6   33.1  91.5     1.2      M    M
 19500  -12.3   9.9   215   20   10   1.3   0.7   31.6  88.8    -0.2   1419  7.2
 19000  -12.5   9.5   205   15    8   3.6   2.0   29.7  85.5    -1.8   1410  7.2
 18500  -11.2  11.8   210   14    7   9.5   5.2   29.5  85.1    -2.0   1358  6.9
 18000   -9.8  14.4   215   13    7   9.5   5.2   29.5  85.1    -2.1   1300  6.6
 17500   -8.4  16.9   215   14    7   9.5   5.2   29.5  85.0    -2.1   1243  6.3
 17000   -7.0  19.4   220   14    7   9.5   5.2   29.4  85.0    -2.2   1186  6.0
 16500   -5.6  21.9   220   15    7   9.5   5.2   29.4  84.9    -2.2   1128  5.7
 16000   -4.1  24.6   220   15    8   9.5   5.2   29.4  84.9    -2.2   1071  5.4
 15500   -2.7  27.1   225   14    7   9.5   5.2   29.3  84.8    -2.3   1013  5.1
 15000   -1.3  29.7   230   14    7   9.5   5.2   29.3  84.7    -2.4    956  4.9
 14500    0.1  32.2   235   13    7   9.5   5.2   29.2  84.6    -2.5    899  4.6
 14000    1.5  34.7   240   13    7   9.5   5.2   29.2  84.5    -2.5    841  4.3
 13500    3.0  37.4   240   13    7   9.5   5.2   29.1  84.4    -2.6    784  4.0
 13000    4.3  39.7   240   12    6   9.1   5.0   29.0  84.2    -2.7    727  3.7
 12500    5.7  42.3   245   12    6   9.1   5.0   28.9  84.1    -2.8    672  3.4
 12000    7.1  44.8   245   12    6   9.2   5.0   28.9  83.9    -2.9    616  3.1
 11500    8.4  47.1   245   13    7   9.2   5.0   28.7  83.7    -3.0    560  2.8
 11000    9.8  49.6   250   14    7   9.2   5.0   28.6  83.5    -3.2    505  2.6
 10500   11.2  52.2   250   14    7   9.2   5.0   28.5  83.3    -3.3    449  2.3
 10250   11.8  53.2   250   15    8   9.0   4.9   28.5  83.3    -3.3    421  2.1
 10000   12.5  54.5   250   14    7   8.8   4.8   28.4  83.1    -3.4    394  2.0
  9750   13.2  55.8   245   13    7   8.8   4.8   28.3  83.0    -3.5    367  1.9
  9500   13.8  56.8   240   12    6   8.8   4.8   28.3  82.9    -3.6    340  1.7
  9250   14.5  58.1   235   11    6   8.8   4.8   28.2  82.7    -3.7    313  1.6
  9000   15.1  59.2   230   10    5   8.8   4.8   28.1  82.6    -3.8    286  1.5
  8750   15.8  60.4   225    9    5   8.8   4.8   28.0  82.4    -3.9    259  1.3
  8500   16.4  61.5   220    8    4   8.8   4.8   27.9  82.3    -4.0    232  1.2
  8250   17.1  62.8   210    7    4   8.8   4.8   27.9  82.2    -4.0    205  1.0
  8000   17.7  63.9   200    6    3   8.6   4.7   27.8  82.0    -4.1    178  0.9
  7750   18.2  64.8   185    8    4   4.8   2.6   27.6  81.6    -4.4    155  0.8
  7500   18.4  65.1   170   10    5   1.9   1.1   27.0  80.6    -5.0    143  0.7
  7250   18.6  65.5   165   13    6   3.8   2.1   26.5  79.7    -5.5    130  0.7
  7000   18.7  65.7   160   15    8  -0.6  -0.3   25.9  78.7    -6.1    118  0.6
  6750   18.3  64.9   155   15    7 -10.1  -5.6   24.8  76.6    -7.3    124  0.6
  6500   17.7  63.9   155   13    7  -0.4  -0.2   23.4  74.1    -8.7    135  0.7
  6250   18.2  64.8   145   11    6   9.2   5.0   23.2  73.8    -8.9    111  0.6
  6000   18.8  65.8   140    9    5   7.8   4.3   23.0  73.4    -9.1     88  0.4
  5750   19.3  66.7   135    9    5   4.0   2.2   22.8  73.1    -9.3     64  0.3
  5500   19.4  66.9   130    9    5   3.4   1.8   22.2  72.0   -10.0     54  0.3
  5250   19.4  66.9   125    9    5 -12.3  -6.7   21.5  70.7   -10.8     47  0.2
  5000   16.8  62.2   125    9    5 -54.0 -29.6   18.2  64.8   -14.1    116  0.6

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

           06/03/2015 at 0900 MDT          |       06/03/2015 at 1200 MDT
                                           |
K index... +5.3  LI... +277.2              | K index... +2.4  LI... +276.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -60.9 -77.6  260  39 20   2.5   1.4 | -60.7 -77.3  250  36 19   2.2   1.2
 45000 -57.5 -71.5  260  59 31   0.9   0.5 | -57.8 -72.0  250  61 32   0.6   0.3
 40000 -56.2 -69.2  265  68 35   1.3   0.7 | -56.9 -70.4  250  66 34   1.2   0.6
 38000 -53.4 -64.1  260  64 33   5.0   2.7 | -53.9 -65.0  250  63 33   5.3   2.9
 36000 -50.4 -58.7  255  59 30   5.0   2.7 | -50.7 -59.3  245  60 31   5.3   2.9
 34000 -45.7 -50.3  250  55 28   8.4   4.6 | -45.8 -50.4  240  58 30   8.5   4.7
 32000 -40.6 -41.1  245  53 27   8.4   4.6 | -40.7 -41.3  240  56 29   8.6   4.7
 30000 -35.7 -32.3  245  49 25   8.0   4.4 | -35.7 -32.3  240  53 27   8.2   4.5
 29000 -33.3 -27.9  245  47 24   8.0   4.4 | -33.2 -27.8  240  51 26   8.2   4.5
 28000 -30.9 -23.6  245  45 23   8.0   4.4 | -30.7 -23.3  240  49 25   8.3   4.5
 27000 -28.6 -19.5  245  43 22   7.6   4.2 | -28.5 -19.3  235  46 24   7.3   4.0
 26000 -26.3 -15.3  245  39 20   7.6   4.2 | -26.3 -15.3  235  43 22   7.3   4.0
 25000 -24.1 -11.4  240  36 19   7.6   4.2 | -24.1 -11.4  235  39 20   7.4   4.0
 24000 -21.7  -7.1  240  34 17   7.9   4.3 | -21.7  -7.1  235  37 19   8.2   4.5
 23000 -19.4  -2.9  235  32 17   7.9   4.3 | -19.3  -2.7  230  34 18   8.2   4.5
 22000 -17.0   1.4  235  31 16   7.9   4.3 | -16.8   1.8  230  32 16   8.3   4.5
 21000 -14.9   5.2  235  28 15   6.7   3.7 | -14.5   5.9  225  29 15   7.1   3.9
 20000 -12.9   8.8  230  26 13   6.6   3.6 | -12.4   9.7  225  27 14   7.1   3.9
 19500 -11.9  10.6  230  24 12   6.6   3.6 | -11.3  11.7  220  26 13   7.1   3.9
 19000 -10.9  12.4  230  23 12   6.6   3.6 | -10.2  13.6  220  25 13   7.1   3.9
 18500  -9.9  14.2  230  21 11   6.3   3.5 |  -9.2  15.4  215  23 12   7.0   3.8
 18000  -9.0  15.8  230  19 10   6.4   3.5 |  -8.1  17.4  215  21 11   7.1   3.9
 17500  -8.0  17.6  225  18  9   6.5   3.6 |  -7.1  19.2  215  20 10   6.1   3.4
 17000  -7.1  19.2  225  17  9   6.6   3.6 |  -6.2  20.8  210  18  9   6.1   3.3
 16500  -6.1  21.0  225  15  8   7.1   3.9 |  -5.4  22.3  210  16  8   6.0   3.3
 16000  -5.0  23.0  225  16  8   8.0   4.4 |  -4.5  23.9  205  15  8   5.9   3.2
 15500  -3.2  26.2  220  17  9   8.4   4.6 |  -3.2  26.2  205  14  7   6.3   3.5
 15000  -2.0  28.4  220  17  9   8.7   4.7 |  -2.3  27.9  200  15  8   6.6   3.6
 14500  -0.7  30.7  215  17  9   8.8   4.8 |  -1.3  29.7  200  15  8   7.2   3.9
 14000   0.7  33.3  215  17  9   9.2   5.1 |  -0.1  31.8  200  15  8   8.7   4.8
 13500   2.1  35.8  220  17  9   9.2   5.0 |   1.2  34.2  200  16  8   8.7   4.8
 13000   3.4  38.1  220  16  8   8.8   4.8 |   2.5  36.5  195  16  8   9.4   5.1
 12500   4.7  40.5  220  16  8   8.9   4.9 |   3.8  38.8  195  15  8   9.3   5.1
 12000   6.0  42.8  220  15  8   8.7   4.8 |   5.2  41.4  195  15  8   9.3   5.1
 11500   7.3  45.1  220  14  7   8.9   4.9 |   6.6  43.9  195  15  8   9.5   5.2
 11000   8.5  47.3  220  13  7   7.1   3.9 |   7.9  46.2  195  15  8   7.9   4.3
 10500   9.6  49.3  215  12  6   9.5   5.2 |   9.0  48.2  200  14  7  10.5   5.8
 10250  10.4  50.7  215  12  6  10.3   5.6 |  10.0  50.0  200  14  7  11.1   6.1
 10000  11.0  51.8  215  11  6   7.3   4.0 |  10.6  51.1  195  14  7   8.1   4.4
  9750  11.6  52.9  215  11  6   7.5   4.1 |  11.2  52.2  195  13  7   8.9   4.9
  9500  12.1  53.8  210  11  5   7.5   4.1 |  11.9  53.4  195  13  7   8.6   4.7
  9250  12.7  54.9  210  10  5   7.4   4.1 |  12.5  54.5  195  12  6   8.1   4.4
  9000  13.2  55.8  205  10  5   7.2   3.9 |  13.1  55.6  195  11  6   8.2   4.5
  8750  13.8  56.8  205  10  5   7.2   3.9 |  13.7  56.7  195  11  6   8.7   4.8
  8500  14.3  57.7  205  10  5   7.1   3.9 |  14.3  57.7  195  10  5   8.8   4.8
  8250  14.8  58.6  200  10  5   6.9   3.8 |  15.0  59.0  190  10  5  10.0   5.5
  8000  15.3  59.5  200  10  5   5.1   2.8 |  15.8  60.4  190   9  5   9.9   5.5
  7750  15.6  60.1  195  11  6   3.9   2.2 |  16.4  61.5  195   9  5   9.0   4.9
  7500  15.9  60.6  190  11  6   4.1   2.2 |  17.1  62.8  195   9  5   9.7   5.3
  7250  16.2  61.2  185  12  6   3.8   2.1 |  17.9  64.2  195   9  5  10.7   5.8
  7000  16.5  61.7  180  13  7   3.3   1.8 |  18.7  65.7  195   9  5  10.5   5.8
  6750  16.7  62.1  180  13  7   1.9   1.0 |  19.5  67.1  195   9  5   9.7   5.3
  6500  16.8  62.2  175  13  7   3.2   1.7 |  20.2  68.4  195   9  4  10.5   5.7
  6250  17.0  62.6  170  11  6   4.6   2.5 |  21.0  69.8  195   9  4  11.4   6.3
  6000  17.3  63.1  165  10  5   5.0   2.7 |  21.9  71.4  195   8  4  10.5   5.8
  5750  17.7  63.9  165   8  4   7.9   4.3 |  22.6  72.7  195   8  4  10.7   5.9
  5500  18.4  65.1  165   7  4   9.8   5.4 |  23.5  74.3  200   8  4  14.1   7.7
  5250  19.1  66.4  160   7  4   9.3   5.1 |  24.6  76.3  200   8  4  16.8   9.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/03/2015 at 1500 MDT          |       06/03/2015 at 1800 MDT
                                           |
K index... +10.5  LI... +275.8             | K index... +9.7  LI... +275.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -60.1 -76.2  240  35 18   2.4   1.3 | -59.3 -74.7  235  35 18   2.4   1.3
 45000 -57.2 -71.0  245  62 32  -0.2  -0.1 | -56.4 -69.5  245  56 29  -0.3  -0.2
 40000 -57.5 -71.5  240  68 35   0.3   0.2 | -56.9 -70.4  235  66 34  -0.4  -0.2
 38000 -54.2 -65.6  240  66 34   5.9   3.2 | -54.0 -65.2  235  64 33   5.3   2.9
 36000 -50.7 -59.3  235  63 32   5.9   3.2 | -50.8 -59.4  230  62 32   5.3   2.9
 34000 -45.7 -50.3  235  61 31   8.3   4.6 | -46.1 -51.0  225  61 31   8.0   4.4
 32000 -40.7 -41.3  230  59 30   8.3   4.6 | -41.3 -42.3  225  60 31   8.0   4.4
 30000 -35.8 -32.4  235  56 29   8.1   4.5 | -36.5 -33.7  230  56 29   8.0   4.4
 29000 -33.4 -28.1  235  54 28   8.1   4.5 | -34.1 -29.4  230  52 27   8.0   4.4
 28000 -30.9 -23.6  235  52 27   8.1   4.5 | -31.7 -25.1  230  49 25   8.0   4.4
 27000 -28.5 -19.3  235  50 26   7.9   4.3 | -29.3 -20.7  230  47 24   7.9   4.3
 26000 -26.1 -15.0  235  48 25   7.9   4.3 | -26.9 -16.4  230  45 23   7.9   4.3
 25000 -23.8 -10.8  235  46 24   7.9   4.3 | -24.5 -12.1  230  43 22   7.9   4.3
 24000 -21.5  -6.7  235  43 22   7.3   4.0 | -22.2  -8.0  230  42 21   7.7   4.2
 23000 -19.3  -2.7  235  40 20   7.3   4.0 | -19.9  -3.8  230  40 20   7.7   4.2
 22000 -17.1   1.2  230  36 19   7.3   4.0 | -17.6   0.3  230  38 19   7.7   4.2
 21000 -14.8   5.4  230  34 17   7.5   4.1 | -15.3   4.5  230  36 18   7.4   4.1
 20000 -12.6   9.3  225  32 16   7.5   4.1 | -13.1   8.4  225  34 17   7.4   4.1
 19500 -11.5  11.3  225  31 16   7.5   4.1 | -12.0  10.4  225  33 17   7.5   4.1
 19000 -10.3  13.5  225  30 15   7.3   4.0 | -10.9  12.4  225  32 16   7.5   4.1
 18500  -9.3  15.3  220  29 15   6.7   3.7 |  -9.8  14.4  225  31 16   7.5   4.1
 18000  -8.3  17.1  220  28 14   6.7   3.7 |  -8.7  16.3  225  30 15   7.6   4.1
 17500  -7.3  18.9  220  27 14   7.0   3.9 |  -7.5  18.5  220  28 15   7.9   4.3
 17000  -6.2  20.8  215  25 13   7.1   3.9 |  -6.4  20.5  220  27 14   8.0   4.4
 16500  -5.2  22.6  215  24 12   7.1   3.9 |  -5.2  22.6  220  26 13   8.0   4.4
 16000  -3.6  25.5  210  23 12   7.2   4.0 |  -4.0  24.8  220  25 13   8.1   4.4
 15500  -2.6  27.3  210  22 11   7.7   4.2 |  -2.2  28.0  220  24 12   8.5   4.6
 15000  -1.4  29.5  205  21 11   7.9   4.4 |  -0.9  30.4  215  23 12   8.8   4.8
 14500  -0.3  31.5  205  20 10   8.1   4.4 |   0.4  32.7  215  23 12   8.8   4.9
 14000   0.9  33.6  205  20 10   8.4   4.6 |   1.8  35.2  215  22 11   9.1   5.0
 13500   2.2  36.0  200  19 10   8.4   4.6 |   3.1  37.6  215  22 11   9.1   5.0
 13000   3.4  38.1  200  18 10   8.6   4.7 |   4.5  40.1  210  22 11   9.1   5.0
 12500   4.7  40.5  195  18  9   8.5   4.7 |   5.8  42.4  210  22 11   9.1   5.0
 12000   6.0  42.8  195  17  9   9.1   5.0 |   7.1  44.8  205  22 11   9.0   5.0
 11500   7.4  45.3  190  16  8   9.2   5.0 |   8.5  47.3  205  21 11   9.2   5.0
 11000   8.6  47.5  190  15  8   8.1   4.4 |   9.7  49.5  200  20 10   8.0   4.4
 10500   9.8  49.6  190  14  7  10.0   5.5 |  10.9  51.6  200  19 10   9.8   5.4
 10250  10.7  51.3  190  13  7  11.6   6.4 |  11.8  53.2  200  19 10  11.7   6.4
 10000  11.5  52.7  190  13  7   9.8   5.4 |  12.5  54.5  200  18  9   9.5   5.2
  9750  12.2  54.0  190  13  7   9.7   5.3 |  13.2  55.8  200  18  9   9.2   5.0
  9500  12.9  55.2  190  13  7   9.8   5.4 |  13.9  57.0  200  17  9   9.3   5.1
  9250  13.6  56.5  190  13  7   9.6   5.3 |  14.6  58.3  200  17  9   9.2   5.0
  9000  14.4  57.9  190  13  6   9.7   5.3 |  15.3  59.5  200  17  9   9.4   5.2
  8750  15.1  59.2  190  12  6   9.9   5.4 |  16.0  60.8  200  16  8   9.8   5.4
  8500  15.8  60.4  190  12  6   9.8   5.4 |  16.7  62.1  200  16  8   9.4   5.2
  8250  16.6  61.9  190  12  6  11.1   6.1 |  17.5  63.5  200  16  8  10.7   5.9
  8000  17.5  63.5  190  12  6  10.7   5.9 |  18.3  64.9  200  16  8  10.4   5.7
  7750  18.2  64.8  190  12  6   9.4   5.2 |  19.0  66.2  200  15  8   9.0   4.9
  7500  18.9  66.0  190  12  6   9.8   5.4 |  19.7  67.5  200  15  8   9.4   5.2
  7250  19.6  67.3  190  12  6   9.9   5.5 |  20.4  68.7  200  15  8  10.0   5.5
  7000  20.4  68.7  190  11  6  10.2   5.6 |  21.2  70.2  200  15  7  10.2   5.6
  6750  21.1  70.0  190  11  6  10.1   5.6 |  21.9  71.4  200  14  7   9.6   5.3
  6500  21.9  71.4  190  11  6  10.6   5.8 |  22.6  72.7  200  14  7  10.0   5.5
  6250  22.7  72.9  190  11  6  11.2   6.2 |  23.4  74.1  200  14  7  10.8   5.9
  6000  23.6  74.5  190  10  5  11.0   6.0 |  24.2  75.6  200  13  7  10.7   5.9
  5750  24.4  75.9  190  10  5  10.9   6.0 |  25.0  77.0  200  12  6  10.3   5.7
  5500  25.3  77.5  190   9  5  13.6   7.4 |  25.7  78.3  200  11  6   9.6   5.3
  5250  26.4  79.5  195   9  5  17.5   9.6 |  26.4  79.5  200  11  6   8.5   4.7
  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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