Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231254
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0654 MDT Monday, May 23, 2016

This forecast is for Monday, May 23, 2016:

If the trigger temperature of 61.5 F/16.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1189 ft/min (6.0 m/s)
   Maximum height of thermals.................. 18310 ft MSL (13471 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 C
Time of trigger temperature.................... 1000 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................. 14582 ft MSL (9743 ft AGL)
Thermal soaring outlook for Tuesday 05/24...... Good

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

Remarks...

Sunrise/Sunset.................... 05:54:39 / 20:27:04 MDT
Total possible sunshine........... 14 hr 32 min 25 sec (872 min 25 sec)
Altitude of sun at 13:11:03 MDT... 71.63 degrees

Upper air data from rawinsonde observation taken on 05/23/2016 at 0600 MDT

Freezing level.................. 11199 ft MSL (6360 ft AGL)
Convective condensation level... 16527 ft MSL (11688 ft AGL)
Lifted condensation level....... 17740 ft MSL (12901 ft AGL)
Lifted index.................... +1.2
K index......................... +4.8

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  -56.9 -70.4   240   48   25  -2.4  -1.3  105.2 221.4    46.5      M    M
 45000  -58.0 -72.4   235   48   25   7.2   4.0   78.6 173.4    33.4      M    M
 40000  -53.8 -64.8   230   51   26   1.6   0.9   62.2 143.9    25.0      M    M
 38000  -54.9 -66.8   230   58   30  -7.6  -4.2   51.9 125.3    18.8      M    M
 36000  -58.2 -72.8   225   64   33   6.7   3.7   38.4 101.1    10.0      M    M
 34000  -52.1 -61.8   225   71   36   8.6   4.7   37.6  99.8     9.8      M    M
 32000  -46.6 -51.9   225   69   35   9.1   5.0   37.3  99.1     9.8      M    M
 30000  -41.7 -43.1   230   65   33   7.2   3.9   36.0  96.7     9.0      M    M
 29000  -39.4 -38.9   230   62   32   8.1   4.4   35.1  95.1     8.5      M    M
 28000  -37.0 -34.6   230   60   31   7.9   4.3   34.3  93.8     8.0      M    M
 27000  -34.6 -30.3   225   57   29   8.1   4.4   33.7  92.6     7.6      M    M
 26000  -32.1 -25.8   225   55   28   9.1   5.0   33.2  91.7     7.3      M    M
 25000  -30.8 -23.4   225   52   27   4.2   2.3   31.2  88.2     5.8      M    M
 24000  -27.9 -18.2   230   49   25   7.9   4.3   31.2  88.1     5.8      M    M
 23000  -26.1 -15.0   230   46   24   6.5   3.6   29.8  85.6     4.7      M    M
 22000  -24.0 -11.2   230   44   23   8.6   4.7   28.9  84.0     4.0      M    M
 21000  -21.8  -7.2   230   41   21   5.3   2.9   27.9  82.2     3.3      M    M
 20000  -19.6  -3.3   230   38   20   7.2   3.9   27.0  80.6     2.6      M    M
 19500  -18.5  -1.3   230   37   19   6.1   3.3   26.5  79.8     2.2      M    M
 19000  -17.9  -0.2   235   35   18   4.3   2.4   25.6  78.1     1.4      M    M
 18500  -16.9   1.6   235   34   17  -0.6  -0.3   24.2  75.5     0.2      M    M
 18000  -16.6   2.1   235   33   17   6.4   3.5   22.9  73.2    -1.0   1168  5.9
 17500  -15.5   4.1   235   33   17   6.5   3.6   22.5  72.5    -1.3   1120  5.7
 17000  -14.7   5.5   235   33   17   6.1   3.3   21.8  71.3    -2.0   1082  5.5
 16500  -13.7   7.3   235   32   17   8.4   4.6   21.4  70.5    -2.5   1036  5.3
 16000  -12.4   9.7   235   32   16   8.6   4.7   21.2  70.1    -2.6    981  5.0
 15500  -11.0  12.2   235   29   15   8.9   4.9   21.0  69.8    -2.8    926  4.7
 15000   -9.7  14.5   235   27   14   8.9   4.9   20.9  69.5    -2.9    872  4.4
 14500   -8.3  17.1   240   25   13   8.9   4.9   20.7  69.3    -3.0    817  4.1
 14000   -7.0  19.4   240   23   12   8.9   4.9   20.6  69.2    -3.1    762  3.9
 13500   -5.7  21.7   240   22   12   8.9   4.9   20.5  68.9    -3.3    707  3.6
 13000   -4.3  24.3   240   22   11   8.9   4.9   20.4  68.7    -3.4    652  3.3
 12500   -3.0  26.6   235   20   10   9.1   5.0   20.2  68.4    -3.6    597  3.0
 12000   -1.7  28.9   225   18    9   7.5   4.1   20.0  68.0    -3.8    544  2.8
 11500   -0.6  30.9   220   14    7   7.4   4.1   19.6  67.2    -4.3    497  2.5
 11000    0.5  32.9   215   11    6   7.4   4.1   19.2  66.5    -4.7    449  2.3
 10500    1.6  34.9   205    7    4   7.4   4.0   18.8  65.9    -5.0    401  2.0
 10250    2.1  35.8   195    6    3   7.7   4.2   18.7  65.6    -5.2    378  1.9
 10000    2.6  36.7   180    5    2   6.0   3.3   18.5  65.3    -5.4    354  1.8
  9750    3.0  37.4   160    3    2   3.7   2.0   18.1  64.5    -5.8    337  1.7
  9500    3.2  37.8   120    3    1   3.4   1.9   17.6  63.6    -6.3    322  1.6
  9250    3.5  38.3   085    3    2   4.6   2.5   17.1  62.8    -6.8    307  1.6
  9000    3.9  39.0   065    5    2   8.1   4.5   16.8  62.3    -7.1    286  1.5
  8750    4.6  40.3   065    6    3   9.5   5.2   16.8  62.2    -7.2    258  1.3
  8500    5.3  41.5   060    6    3   9.2   5.0   16.7  62.1    -7.3    230  1.2
  8250    6.0  42.8   060    7    4   9.1   5.0   16.7  62.1    -7.3    202  1.0
  8000    6.7  44.1   060    8    4   9.7   5.3   16.7  62.0    -7.4    174  0.9
  7750    7.3  45.1   055    9    5   7.4   4.0   16.6  61.9    -7.5    146  0.7
  7500    7.7  45.9   050   10    5   2.0   1.1   16.2  61.2    -7.9    129  0.7
  7250    7.8  46.0   050   11    6   4.3   2.4   15.6  60.1    -8.5    117  0.6
  7000    8.3  46.9   045   12    6   7.6   4.2   15.4  59.7    -8.7     94  0.5
  6750    8.9  48.0   045   10    5   6.7   3.7   15.2  59.3    -9.0     72  0.4
  6500    9.4  48.9   045    8    4   6.9   3.8   15.0  58.9    -9.2     49  0.2
  6250    9.9  49.8   050    6    3   6.8   3.8   14.7  58.5    -9.5     26  0.1
  6000   10.4  50.7   055    4    2   7.0   3.8   14.5  58.1    -9.7      4  0.0
  5750   10.9  51.6   060    3    1   6.4   3.5   14.3  57.7    -9.9      M    M
  5500   11.4  52.5   060    2    1   8.6   4.7   14.1  57.3   -10.2      M    M
  5250   11.9  53.4   060    1    1   0.5   0.3   13.9  57.0   -10.4      M    M
  5000   11.1  52.0   060    1    0 -22.9 -12.5   12.3  54.1   -12.1      M    M

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

           05/23/2016 at 0900 MDT          |       05/23/2016 at 1200 MDT
                                           |
K index... +18.0  LI... +274.4             | K index... +20.8  LI... +272.7
CAPE... 0.0  CIN... M                      | CAPE... +20.8  CIN... -28.3
                                           |
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 -55.6 -68.1  245  38 19   0.6   0.3 | -56.0 -68.8  245  35 18   0.5   0.3
 45000 -54.7 -66.5  245  47 24   1.1   0.6 | -55.3 -67.5  250  49 25   0.5   0.3
 40000 -53.1 -63.6  245  57 29   1.1   0.6 | -54.6 -66.3  260  69 36   0.5   0.3
 38000 -52.7 -62.9  240  60 31   0.1   0.0 | -53.4 -64.1  260  71 37   2.8   1.5
 36000 -52.7 -62.9  235  62 32   0.1   0.0 | -51.8 -61.2  260  70 36   2.8   1.5
 34000 -52.2 -62.0  235  65 33   6.9   3.8 | -49.7 -57.5  260  68 35   5.9   3.2
 32000 -48.1 -54.6  230  64 33   6.1   3.4 | -46.1 -51.0  255  63 32   5.9   3.2
 30000 -44.0 -47.2  230  63 32   8.5   4.7 | -42.5 -44.5  255  58 30   7.3   4.0
 29000 -41.4 -42.5  230  61 31   8.6   4.7 | -40.3 -40.5  250  57 30   7.3   4.0
 28000 -38.8 -37.8  230  59 30   8.6   4.7 | -38.1 -36.6  250  57 29   7.3   4.0
 27000 -36.3 -33.3  230  57 29   8.1   4.5 | -35.9 -32.6  245  56 29   7.1   3.9
 26000 -33.9 -29.0  230  54 28   7.9   4.3 | -33.5 -28.3  245  53 27   6.4   3.5
 25000 -31.6 -24.9  230  51 26   7.9   4.3 | -31.6 -24.9  245  50 26   6.4   3.5
 24000 -29.2 -20.6  230  49 25   7.8   4.3 | -29.7 -21.5  245  47 24   6.8   3.7
 23000 -26.9 -16.4  235  47 24   7.6   4.2 | -27.6 -17.7  240  44 23   7.0   3.9
 22000 -24.7 -12.5  235  45 23   7.6   4.2 | -25.5 -13.9  240  42 22   7.1   3.9
 21000 -22.4  -8.3  235  43 22   6.4   3.5 | -23.4 -10.1  240  39 20   7.0   3.9
 20000 -20.6  -5.1  235  40 21   6.0   3.3 | -21.3  -6.3  240  36 19   7.0   3.9
 19500 -19.7  -3.5  235  38 20   6.0   3.3 | -20.3  -4.5  240  34 18   7.0   3.9
 19000 -18.8  -1.8  235  37 19   6.0   3.3 | -19.2  -2.6  240  33 17   7.0   3.9
 18500 -17.9  -0.2  235  35 18   5.8   3.2 | -18.2  -0.8  240  31 16   7.1   3.9
 18000 -17.1   1.2  235  33 17   5.7   3.1 | -17.1   1.2  235  29 15   7.1   3.9
 17500 -16.3   2.7  235  30 16   5.7   3.1 | -16.1   3.0  235  27 14   7.3   4.0
 17000 -15.3   4.5  230  28 14   8.1   4.5 | -14.9   5.2  230  25 13   8.3   4.5
 16500 -14.1   6.6  230  26 13   8.0   4.4 | -13.7   7.3  225  23 12   8.3   4.5
 16000 -13.0   8.6  230  23 12   8.4   4.6 | -12.5   9.5  220  21 11   8.3   4.6
 15500 -11.1  12.0  225  20 10   8.5   4.6 | -11.3  11.7  220  20 10   8.3   4.6
 15000  -9.7  14.5  225  18  9   9.3   5.1 | -10.1  13.8  215  18  9   8.5   4.7
 14500  -8.3  17.1  225  17  9   9.3   5.1 |  -8.8  16.2  215  18  9   8.6   4.7
 14000  -7.0  19.4  225  15  8   8.8   4.8 |  -7.6  18.3  215  17  9   8.8   4.8
 13500  -5.7  21.7  225  14  7   8.7   4.8 |  -6.2  20.8  215  16  8   9.1   5.0
 13000  -4.4  24.1  220  13  7   9.0   4.9 |  -4.2  24.4  215  15  8   8.9   4.9
 12500  -3.0  26.6  220  13  7   9.1   5.0 |  -2.9  26.8  215  15  8   8.9   4.9
 12000  -1.6  29.1  215  13  7   8.6   4.7 |  -1.6  29.1  220  14  7   9.0   4.9
 11500  -0.4  31.3  210  13  7   8.2   4.5 |  -0.3  31.5  220  14  7   9.0   4.9
 11000   0.8  33.4  210  13  6   7.4   4.1 |   1.1  34.0  220  13  7   8.3   4.6
 10500   1.8  35.2  200  12  6   6.5   3.5 |   2.3  36.1  220  12  6   7.7   4.2
 10250   2.4  36.3  200  12  6   8.8   4.8 |   2.9  37.2  220  12  6   9.6   5.3
 10000   3.1  37.6  195  12  6   9.1   5.0 |   3.6  38.5  215  11  6   9.9   5.4
  9750   3.7  38.7  195  12  6   6.9   3.8 |   4.3  39.7  215  11  6   8.3   4.5
  9500   4.2  39.6  190  11  6   7.6   4.1 |   4.9  40.8  215  10  5   8.7   4.8
  9250   4.8  40.6  185  11  6   7.0   3.8 |   5.6  42.1  215   9  5   8.6   4.7
  9000   5.3  41.5  185  11  6   6.6   3.6 |   6.2  43.2  210   9  4   8.7   4.8
  8750   5.8  42.4  180  11  5   6.7   3.7 |   6.8  44.2  210   8  4   8.8   4.8
  8500   6.3  43.3  180  10  5   6.7   3.7 |   7.5  45.5  210   7  4   8.3   4.5
  8250   6.8  44.2  175  10  5   6.5   3.6 |   8.1  46.6  205   7  4  10.3   5.6
  8000   7.2  45.0  170  10  5   5.5   3.0 |   8.9  48.0  205   7  3  10.6   5.8
  7750   7.6  45.7  170   9  5   4.7   2.6 |   9.6  49.3  210   7  3   8.8   4.9
  7500   7.9  46.2  165   8  4   4.7   2.6 |  10.3  50.5  210   7  3   9.3   5.1
  7250   8.3  46.9  160   8  4   4.4   2.4 |  11.0  51.8  210   6  3  10.7   5.9
  7000   8.6  47.5  155   7  3   4.2   2.3 |  11.9  53.4  210   6  3  11.2   6.1
  6750   8.8  47.8  145   6  3   3.4   1.9 |  12.6  54.7  210   6  3   9.5   5.2
  6500   9.1  48.4  140   5  3   4.8   2.6 |  13.3  55.9  210   6  3  10.1   5.6
  6250   9.6  49.3  135   5  2   7.4   4.0 |  14.2  57.6  210   6  3  11.5   6.3
  6000  10.1  50.2  125   4  2   8.3   4.6 |  15.0  59.0  215   6  3  11.5   6.3
  5750  10.7  51.3  120   3  2  10.0   5.5 |  15.8  60.4  215   6  3  10.6   5.8
  5500  11.5  52.7  120   3  2  11.0   6.0 |  16.7  62.1  215   6  3  13.1   7.2
  5250  12.3  54.1  120   3  2   9.9   5.4 |  17.8  64.0  215   6  3  18.0   9.9
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/23/2016 at 1500 MDT          |       05/23/2016 at 1800 MDT
                                           |
K index... +22.1  LI... +273.1             | K index... +20.8  LI... +273.7
CAPE... 0.0  CIN... -15.3                  | 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 -56.8 -70.2  245  33 17   0.2   0.1 | -57.8 -72.0  240  38 19  -0.4  -0.2
 45000 -56.6 -69.9  255  51 26  -0.2  -0.1 | -58.3 -72.9  255  52 27   0.5   0.3
 40000 -56.9 -70.4  260  79 41  -0.2  -0.1 | -57.5 -71.5  255  72 37   0.6   0.3
 38000 -54.8 -66.6  260  81 42   5.2   2.9 | -55.0 -67.0  255  74 38   5.8   3.2
 36000 -51.7 -61.1  260  79 40   5.2   2.9 | -51.5 -60.7  255  72 37   5.8   3.2
 34000 -48.4 -55.1  260  76 39   6.4   3.5 | -48.0 -54.4  255  71 36   6.0   3.3
 32000 -44.5 -48.1  260  73 38   6.5   3.6 | -44.4 -47.9  255  68 35   6.0   3.3
 30000 -40.5 -40.9  260  69 36   7.4   4.1 | -40.5 -40.9  255  65 34   7.7   4.2
 29000 -38.3 -36.9  260  67 34   7.4   4.1 | -38.2 -36.8  255  64 33   7.8   4.3
 28000 -36.0 -32.8  260  64 33   7.4   4.1 | -35.8 -32.4  255  63 32   7.8   4.3
 27000 -33.3 -27.9  255  61 31   6.4   3.5 | -33.0 -27.4  255  61 31   6.9   3.8
 26000 -31.4 -24.5  255  58 30   6.5   3.6 | -30.9 -23.6  255  58 30   7.0   3.8
 25000 -29.4 -20.9  255  54 28   6.5   3.6 | -28.9 -20.0  255  56 29   7.0   3.8
 24000 -27.5 -17.5  255  51 26   6.5   3.5 | -26.8 -16.2  255  53 27   7.0   3.8
 23000 -25.6 -14.1  250  48 25   6.4   3.5 | -24.7 -12.5  255  49 25   7.0   3.8
 22000 -23.7 -10.7  250  45 23   6.5   3.5 | -22.6  -8.7  255  46 23   7.0   3.8
 21000 -21.8  -7.2  250  42 22   6.3   3.5 | -20.5  -4.9  255  42 22   6.5   3.5
 20000 -19.9  -3.8  250  37 19   6.3   3.5 | -18.6  -1.5  250  39 20   6.6   3.6
 19500 -19.0  -2.2  245  35 18   6.4   3.5 | -17.6   0.3  250  37 19   6.6   3.6
 19000 -18.1  -0.6  245  33 17   6.4   3.5 | -16.7   1.9  250  35 18   6.6   3.6
 18500 -17.1   1.2  240  30 16   7.3   4.0 | -15.7   3.7  245  34 17   7.0   3.9
 18000 -16.0   3.2  240  28 15   7.6   4.2 | -14.7   5.5  245  31 16   7.2   3.9
 17500 -14.9   5.2  235  26 14   7.8   4.3 | -13.6   7.5  240  29 15   7.4   4.0
 17000 -13.7   7.3  230  24 12   8.5   4.7 | -12.5   9.5  240  27 14   7.9   4.3
 16500 -12.5   9.5  225  22 12   8.5   4.7 | -11.4  11.5  235  25 13   7.9   4.3
 16000 -11.3  11.7  220  21 11   8.1   4.5 | -10.2  13.6  230  23 12   8.1   4.4
 15500 -10.1  13.8  215  20 10   8.1   4.5 |  -9.1  15.6  225  21 11   8.1   4.4
 15000  -8.9  16.0  215  19 10   8.2   4.5 |  -7.9  17.8  225  20 10   8.7   4.8
 14500  -7.7  18.1  210  19 10   8.2   4.5 |  -6.5  20.3  220  19 10   9.1   5.0
 14000  -6.5  20.3  210  18  9   8.4   4.6 |  -5.2  22.6  215  18  9   9.2   5.0
 13500  -5.2  22.6  210  18  9   8.7   4.8 |  -3.8  25.2  215  18  9   9.3   5.1
 13000  -3.2  26.2  205  16  8   8.8   4.8 |  -1.7  28.9  210  17  9   8.9   4.9
 12500  -1.9  28.6  205  15  8   8.8   4.8 |  -0.4  31.3  210  16  8   8.8   4.8
 12000  -0.6  30.9  205  14  7   8.5   4.7 |   0.9  33.6  205  15  8   8.5   4.6
 11500   0.6  33.1  205  12  6   8.4   4.6 |   2.1  35.8  205  14  7   8.3   4.6
 11000   1.9  35.4  205  10  5   7.6   4.1 |   3.3  37.9  200  13  7   7.6   4.2
 10500   2.9  37.2  210   8  4   7.0   3.8 |   4.4  39.9  200  12  6   7.2   4.0
 10250   3.5  38.3  215   7  4   8.9   4.9 |   5.0  41.0  200  11  6   9.2   5.0
 10000   4.2  39.6  215   7  3   9.5   5.2 |   5.7  42.3  200  11  6   8.8   4.8
  9750   4.9  40.8  225   6  3   8.0   4.4 |   6.3  43.3  200  10  5   6.9   3.8
  9500   5.5  41.9  230   6  3   8.4   4.6 |   6.8  44.2  200   9  4   7.3   4.0
  9250   6.1  43.0  240   5  3   8.4   4.6 |   7.4  45.3  195   7  4   7.6   4.2
  9000   6.8  44.2  245   5  3   9.5   5.2 |   8.0  46.4  195   7  3   7.4   4.1
  8750   7.5  45.5  250   5  3  10.2   5.6 |   8.5  47.3  200   5  3   7.1   3.9
  8500   8.2  46.8  250   5  3   9.8   5.4 |   9.0  48.2  205   4  2   6.5   3.6
  8250   9.0  48.2  255   5  3  10.9   6.0 |   9.5  49.1  210   3  2   9.0   4.9
  8000   9.8  49.6  255   6  3  10.4   5.7 |  10.3  50.5  215   3  1  10.2   5.6
  7750  10.5  50.9  255   6  3   9.1   5.0 |  10.9  51.6  220   3  1   8.6   4.7
  7500  11.2  52.2  260   6  3   9.3   5.1 |  11.6  52.9  225   3  1   8.8   4.8
  7250  11.9  53.4  260   6  3  10.6   5.8 |  12.3  54.1  235   3  1   9.8   5.4
  7000  12.8  55.0  260   6  3  10.9   6.0 |  13.1  55.6  235   3  1  10.4   5.7
  6750  13.5  56.3  260   6  3   9.2   5.1 |  13.8  56.8  240   3  1   9.6   5.2
  6500  14.2  57.6  260   6  3   9.9   5.4 |  14.5  58.1  240   3  1   9.9   5.4
  6250  15.0  59.0  265   6  3  11.5   6.3 |  15.3  59.5  245   3  1  10.7   5.8
  6000  15.9  60.6  265   6  3  11.9   6.5 |  16.1  61.0  245   3  1  10.9   6.0
  5750  16.8  62.2  265   6  3  11.2   6.2 |  16.9  62.4  250   3  1  10.6   5.8
  5500  17.6  63.7  265   6  3  13.8   7.6 |  17.7  63.9  250   3  1  10.7   5.9
  5250  18.8  65.8  265   6  3  18.9  10.4 |  18.4  65.1  250   3  2  11.2   6.1
  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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