Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 201427
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0827 MDT Wednesday, May 20, 2015

This forecast is for Wednesday, May 20, 2015:

If the trigger temperature of 62.5 F/16.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1035 ft/min (5.3 m/s)
   Maximum height of thermals.................. 16267 ft MSL (11428 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... 1100 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................. 12044 ft MSL (7205 ft AGL)
Thermal soaring outlook for Thursday 05/21..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:57:18 / 20:23:52 MDT
Total possible sunshine........... 14 hr 26 min 34 sec (866 min 34 sec)
Altitude of sun at 13:10:46 MDT... 70.90 degrees

Upper air data from rawinsonde observation taken on 05/20/2015 at 0600 MDT

Freezing level.................. 10615 ft MSL (5776 ft AGL)
Convective condensation level... 12481 ft MSL (7642 ft AGL)
Lifted condensation level....... 13618 ft MSL (8779 ft AGL)
Lifted index.................... -1.0
K index......................... +19.9

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  -56.7 -70.1   245   35   18   6.9   3.8  106.0 222.8    48.5      M    M
 45000  -54.4 -65.9   230   50   26 -11.4  -6.3   85.2 185.3    39.1      M    M
 40000  -56.9 -70.4   255   65   34  -2.8  -1.5   57.7 135.9    23.9      M    M
 38000  -59.0 -74.2   255   79   41   3.9   2.1   44.7 112.5    15.9      M    M
 36000  -54.8 -66.6   260   79   41   8.3   4.5   42.3 108.2    14.7      M    M
 34000  -49.8 -57.6   255   76   39   8.3   4.6   41.0 105.8    14.1      M    M
 32000  -44.9 -48.8   260   72   37   8.1   4.4   39.8 103.6    13.6      M    M
 30000  -40.7 -41.3   265   70   36   6.9   3.8   37.5  99.5    12.2      M    M
 29000  -38.6 -37.5   265   66   34   7.4   4.1   36.4  97.5    11.6      M    M
 28000  -36.4 -33.5   265   63   32   5.9   3.2   35.4  95.7    10.9      M    M
 27000  -34.6 -30.3   260   59   30   7.6   4.2   33.9  93.1     9.9      M    M
 26000  -32.3 -26.1   260   55   28   7.9   4.3   33.1  91.6     9.4      M    M
 25000  -30.3 -22.5   255   45   23   4.6   2.5   32.0  89.6     8.7      M    M
 24000  -28.9 -20.0   250   37   19   5.9   3.2   30.0  86.1     7.2      M    M
 23000  -26.7 -16.1   245   30   15   7.6   4.2   29.1  84.4     6.5      M    M
 22000  -24.1 -11.4   240   23   12   9.0   5.0   28.8  83.9     6.3      M    M
 21000  -21.8  -7.2   245   23   12   5.7   3.1   28.0  82.5     5.8      M    M
 20000  -19.7  -3.5   250   24   12   5.0   2.8   26.2  79.2     4.3      M    M
 19500  -18.9  -2.0   255   22   11   6.8   3.7   25.5  77.9     3.7      M    M
 19000  -17.9  -0.2   255   20   10   4.3   2.4   25.0  77.0     3.2      M    M
 18500  -17.2   1.0   255   20   10   5.7   3.1   24.1  75.3     2.4      M    M
 18000  -16.3   2.7   250   21   11   7.6   4.2   23.4  74.2     1.8      M    M
 17500  -15.2   4.6   250   23   12   7.4   4.0   23.1  73.5     1.5      M    M
 17000  -14.0   6.8   250   24   12   7.9   4.3   22.7  72.8     1.3      M    M
 16500  -13.4   7.9   245   26   13   0.5   0.3   21.7  71.1     0.4      M    M
 16000  -12.9   8.8   245   27   14   5.7   3.1   20.7  69.3    -0.6   1013  5.1
 15500  -11.9  10.6   250   28   14   9.0   4.9   20.2  68.4    -1.0    968  4.9
 15000  -10.6  12.9   250   28   15   8.6   4.7   20.0  68.1    -1.3    915  4.7
 14500   -9.4  15.1   255   29   15   9.0   5.0   19.9  67.7    -1.5    864  4.4
 14000   -8.0  17.6   255   30   15   9.3   5.1   19.8  67.6    -1.6    807  4.1
 13500   -6.6  20.1   250   31   16   9.6   5.3   19.7  67.5    -1.6    750  3.8
 13000   -5.4  22.3   250   32   16   6.3   3.5   19.4  66.9    -1.9    700  3.6
 12500   -4.5  23.9   250   26   13   6.7   3.7   18.9  66.0    -2.5    656  3.3
 12000   -3.6  25.5   255   20   10   7.1   3.9   18.4  65.0    -3.1    615  3.1
 11500   -2.3  27.9   245   18    9   8.8   4.8   18.2  64.7    -3.3    563  2.9
 11000   -1.0  30.2   235   17    9   8.8   4.8   18.0  64.4    -3.5    509  2.6
 10500    0.3  32.5   240   13    7   8.7   4.8   17.8  64.1    -3.7    455  2.3
 10250    0.9  33.6   245   11    6   8.9   4.9   17.8  64.0    -3.7    428  2.2
 10000    1.6  34.9   250   10    5   9.3   5.1   17.7  63.9    -3.8    401  2.0
  9750    2.3  36.1   240   10    5   9.3   5.1   17.7  63.8    -3.9    372  1.9
  9500    3.0  37.4   235   11    5   9.3   5.1   17.6  63.8    -3.9    344  1.7
  9250    3.7  38.7   225   11    6   9.3   5.1   17.6  63.7    -3.9    316  1.6
  9000    4.4  39.9   220   12    6   9.4   5.1   17.6  63.7    -4.0    287  1.5
  8750    5.1  41.2   210   12    6   9.2   5.0   17.6  63.6    -4.0    259  1.3
  8500    5.8  42.4   195   13    7   9.9   5.4   17.5  63.5    -4.1    231  1.2
  8250    6.5  43.7   185   14    7   7.4   4.0   17.5  63.5    -4.1    202  1.0
  8000    6.8  44.2   175   16    8   3.9   2.2   17.1  62.8    -4.5    184  0.9
  7750    7.1  44.8   170   17    9   4.7   2.6   16.7  62.0    -5.0    169  0.9
  7500    7.4  45.3   165   19   10   2.5   1.4   16.3  61.3    -5.4    153  0.8
  7250    7.1  44.8   165   20   10 -11.1  -6.1   15.3  59.5    -6.4    153  0.8
  7000    6.2  43.2   160   22   11  -3.0  -1.7   13.6  56.5    -8.1    173  0.9
  6750    6.7  44.1   155   20   10   8.7   4.8   13.4  56.1    -8.3    151  0.8
  6500    6.9  44.4   150   17    9  -1.2  -0.6   12.9  55.2    -8.9    137  0.7
  6250    6.9  44.4   140   15    8   3.2   1.8   12.1  53.8    -9.7    132  0.7
  6000    7.4  45.3   130   13    7   8.7   4.8   11.9  53.5    -9.9    108  0.5
  5750    7.9  46.2   125   12    6   6.7   3.7   11.8  53.2   -10.1     84  0.4
  5500    8.5  47.3   120   10    5   9.0   5.0   11.6  52.8   -10.4     61  0.3
  5250    9.0  48.2   115    9    5   1.8   1.0   11.4  52.5   -10.6     37  0.2
  5000    8.4  47.1   105    8    4 -16.2  -8.9   10.1  50.2   -11.9     47  0.2

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

           05/20/2015 at 0900 MDT          |       05/20/2015 at 1200 MDT
                                           |
K index... +13.6  LI... +273.4             | K index... +19.8  LI... +272.3
CAPE... +40.4  CIN... -13.6                | CAPE... +113.5  CIN... -14.1
                                           |
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 -58.0 -72.4  240  29 15   1.2   0.6 | -58.7 -73.7  235  30 15   1.1   0.6
 45000 -56.5 -69.7  245  46 24  -2.3  -1.3 | -57.3 -71.1  240  49 25  -1.9  -1.1
 40000 -59.9 -75.8  250  73 38  -2.0  -1.1 | -60.1 -76.2  245  67 35  -1.5  -0.8
 38000 -57.5 -71.5  250  74 38   6.4   3.5 | -57.6 -71.7  245  67 34   6.2   3.4
 36000 -53.7 -64.7  255  72 37   6.4   3.5 | -53.9 -65.0  245  64 33   6.2   3.4
 34000 -49.5 -57.1  255  69 36   8.1   4.4 | -49.7 -57.5  245  60 31   8.5   4.6
 32000 -44.7 -48.5  260  65 33   8.1   4.4 | -44.7 -48.5  250  56 29   8.5   4.6
 30000 -39.9 -39.8  260  61 31   7.8   4.3 | -39.7 -39.5  250  52 27   8.1   4.5
 29000 -37.6 -35.7  260  58 30   7.8   4.3 | -37.3 -35.1  250  49 25   8.1   4.4
 28000 -35.3 -31.5  260  56 29   7.8   4.3 | -34.9 -30.8  250  47 24   8.1   4.5
 27000 -32.4 -26.3  260  53 27   7.3   4.0 | -32.0 -25.6  250  45 23   6.9   3.8
 26000 -30.2 -22.4  260  50 26   7.3   4.0 | -29.9 -21.8  255  42 22   6.9   3.8
 25000 -28.1 -18.6  260  47 24   7.3   4.0 | -27.9 -18.2  255  40 20   6.9   3.8
 24000 -26.0 -14.8  260  43 22   5.3   2.9 | -25.9 -14.6  255  37 19   6.0   3.3
 23000 -24.4 -11.9  260  37 19   5.2   2.8 | -24.0 -11.2  255  34 17   6.1   3.4
 22000 -22.9  -9.2  260  32 16   5.2   2.8 | -22.1  -7.8  255  31 16   6.1   3.4
 21000 -21.2  -6.2  260  27 14   6.3   3.4 | -20.3  -4.5  260  27 14   5.7   3.1
 20000 -19.4  -2.9  260  23 12   6.2   3.4 | -18.6  -1.5  255  23 12   5.7   3.1
 19500 -18.5  -1.3  260  22 11   6.3   3.4 | -17.8  -0.0  255  21 11   5.7   3.1
 19000 -17.6   0.3  260  20 10   6.5   3.6 | -16.9   1.6  255  19 10   5.8   3.2
 18500 -16.7   1.9  260  19 10   4.4   2.4 | -16.1   3.0  255  18  9   5.4   3.0
 18000 -16.0   3.2  260  19 10   4.5   2.5 | -15.2   4.6  255  17  9   5.4   3.0
 17500 -15.4   4.3  255  19 10   5.3   2.9 | -14.4   6.1  250  16  8   5.1   2.8
 17000 -14.4   6.1  255  20 10   6.4   3.5 | -13.7   7.3  250  17  9   4.9   2.7
 16500 -13.5   7.7  255  21 11   6.5   3.5 | -13.0   8.6  245  18  9   5.1   2.8
 16000 -12.4   9.7  255  22 11   7.6   4.2 | -12.1  10.2  240  18  9   7.8   4.3
 15500 -11.3  11.7  255  23 12   7.5   4.1 | -11.0  12.2  240  19 10   7.7   4.2
 15000 -10.2  13.6  255  23 12   7.9   4.3 |  -9.8  14.4  240  19 10   8.6   4.7
 14500  -9.1  15.6  255  24 12   8.0   4.4 |  -8.6  16.5  240  19 10   8.6   4.7
 14000  -7.9  17.8  255  24 12   8.2   4.5 |  -7.4  18.7  240  19 10   8.6   4.7
 13500  -6.7  19.9  255  23 12   8.3   4.5 |  -6.1  21.0  240  18  9   8.6   4.7
 13000  -5.0  23.0  255  22 11   8.3   4.6 |  -4.3  24.3  240  16  8   8.7   4.8
 12500  -3.8  25.2  250  20 10   8.4   4.6 |  -3.0  26.6  240  15  8   8.8   4.8
 12000  -2.6  27.3  250  18  9   8.4   4.6 |  -1.7  28.9  240  14  7   8.8   4.8
 11500  -1.4  29.5  245  15  8   8.4   4.6 |  -0.5  31.1  235  12  6   8.9   4.9
 11000  -0.2  31.6  240  13  7   8.2   4.5 |   0.8  33.4  230  11  6   8.2   4.5
 10500   1.0  33.8  230  10  5   8.9   4.9 |   2.0  35.6  225   9  5   8.9   4.9
 10250   1.6  34.9  225   9  5   5.3   2.9 |   2.6  36.7  225   8  4   5.0   2.7
 10000   1.9  35.4  225   9  5   6.1   3.4 |   2.8  37.0  215   8  4   5.8   3.2
  9750   2.6  36.7  220   8  4  10.3   5.7 |   3.5  38.3  210   7  4  10.1   5.5
  9500   3.3  37.9  215   8  4   9.5   5.2 |   4.2  39.6  205   6  3   8.9   4.9
  9250   3.9  39.0  210   7  4   6.8   3.7 |   4.8  40.6  200   6  3   7.1   3.9
  9000   4.3  39.7  205   7  4   6.1   3.3 |   5.3  41.5  195   5  3   7.2   3.9
  8750   4.9  40.8  200   7  4   8.2   4.5 |   5.9  42.6  190   5  2   8.7   4.8
  8500   5.5  41.9  190   7  4   7.4   4.0 |   6.5  43.7  180   4  2   8.4   4.6
  8250   6.0  42.8  185   7  4   6.7   3.7 |   7.2  45.0  175   4  2   8.7   4.8
  8000   6.5  43.7  180   8  4   6.0   3.3 |   7.8  46.0  170   4  2   9.0   5.0
  7750   6.9  44.4  180   9  5   6.1   3.3 |   8.4  47.1  170   4  2   9.2   5.1
  7500   7.3  45.1  175  10  5   5.0   2.8 |   9.1  48.4  170   4  2   9.7   5.3
  7250   7.7  45.9  170  10  5   3.8   2.1 |   9.9  49.8  170   4  2  10.3   5.6
  7000   7.9  46.2  165  10  5   4.0   2.2 |  10.6  51.1  175   4  2  10.0   5.5
  6750   8.2  46.8  165  10  5   4.9   2.7 |  11.4  52.5  175   4  2   9.9   5.4
  6500   8.7  47.7  160   9  5   7.2   3.9 |  12.1  53.8  175   4  2  10.6   5.8
  6250   9.2  48.6  160   8  4   8.7   4.8 |  12.9  55.2  175   4  2  11.3   6.2
  6000   9.8  49.6  160   7  3   7.1   3.9 |  13.8  56.8  175   4  2  10.2   5.6
  5750  10.3  50.5  160   6  3   8.4   4.6 |  14.5  58.1  180   3  2  12.0   6.6
  5500  11.0  51.8  155   6  3  11.4   6.2 |  15.5  59.9  180   3  2  15.1   8.3
  5250  11.8  53.2  155   5  3   9.5   5.2 |  16.6  61.9  180   3  2  13.5   7.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/20/2015 at 1500 MDT          |       05/20/2015 at 1800 MDT
                                           |
K index... +24.4  LI... +273.3             | K index... +19.0  LI... +272.3
CAPE... +20.0  CIN... -12.7                | CAPE... +56.5  CIN... -32.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.0 -74.2  230  32 16   0.2   0.1 | -58.3 -72.9  235  34 17   0.7   0.4
 45000 -58.8 -73.8  240  48 25  -1.0  -0.5 | -57.5 -71.5  245  45 23  -2.2  -1.2
 40000 -60.1 -76.2  240  68 35  -0.6  -0.3 | -60.7 -77.3  235  68 35  -1.9  -1.0
 38000 -57.6 -71.7  240  68 35   5.9   3.3 | -58.6 -73.5  235  65 33   5.5   3.0
 36000 -54.0 -65.2  240  66 34   5.9   3.3 | -55.3 -67.5  235  58 30   5.5   3.0
 34000 -49.9 -57.8  240  61 32   8.6   4.7 | -51.1 -60.0  235  50 26   9.6   5.3
 32000 -44.7 -48.5  240  53 27   8.6   4.7 | -45.4 -49.7  235  39 20   9.6   5.3
 30000 -39.8 -39.6  245  45 23   7.7   4.2 | -40.0 -40.0  240  31 16   7.8   4.3
 29000 -37.5 -35.5  245  43 22   7.7   4.2 | -37.7 -35.9  240  30 15   7.8   4.3
 28000 -34.7 -30.5  245  39 20   7.7   4.2 | -35.3 -31.5  245  29 15   7.9   4.3
 27000 -32.4 -26.3  245  37 19   7.2   4.0 | -32.6 -26.7  245  28 14   6.7   3.7
 26000 -30.3 -22.5  250  36 19   7.2   4.0 | -30.6 -23.1  250  29 15   6.8   3.7
 25000 -28.1 -18.6  250  35 18   7.2   4.0 | -28.6 -19.5  250  31 16   6.8   3.7
 24000 -26.0 -14.8  250  34 17   7.0   3.9 | -26.6 -15.9  250  31 16   6.6   3.6
 23000 -23.9 -11.0  250  31 16   7.1   3.9 | -24.6 -12.3  245  31 16   6.6   3.6
 22000 -21.8  -7.2  250  28 14   7.1   3.9 | -22.6  -8.7  240  30 16   6.7   3.7
 21000 -19.7  -3.5  245  25 13   7.3   4.0 | -20.5  -4.9  240  30 15   7.6   4.2
 20000 -17.6   0.3  245  21 11   7.3   4.0 | -18.3  -0.9  235  28 14   7.6   4.2
 19500 -16.5   2.3  240  20 10   7.3   4.0 | -17.1   1.2  235  27 14   7.6   4.2
 19000 -15.4   4.3  240  18  9   7.4   4.1 | -16.0   3.2  235  27 14   7.6   4.2
 18500 -14.5   5.9  235  17  9   5.6   3.1 | -14.8   5.4  235  26 13   8.1   4.5
 18000 -13.6   7.5  230  16  8   5.8   3.2 | -13.7   7.3  235  25 13   8.1   4.4
 17500 -12.8   9.0  225  15  8   6.1   3.3 | -12.5   9.5  235  24 12   7.8   4.3
 17000 -11.9  10.6  220  15  8   6.3   3.5 | -11.3  11.7  230  24 12   7.7   4.2
 16500 -11.0  12.2  215  14  7   6.4   3.5 | -10.2  13.6  230  23 12   7.7   4.2
 16000 -10.0  14.0  215  13  7   7.2   4.0 |  -9.0  15.8  225  24 12   7.8   4.3
 15500  -8.9  16.0  210  13  7   7.2   4.0 |  -7.8  18.0  220  24 13   7.7   4.2
 15000  -7.9  17.8  205  12  6   6.7   3.7 |  -6.6  20.1  215  25 13   8.4   4.6
 14500  -6.9  19.6  205  11  6   6.7   3.7 |  -5.4  22.3  215  25 13   8.4   4.6
 14000  -5.9  21.4  200  10  5   6.9   3.8 |  -4.2  24.4  210  25 13   8.0   4.4
 13500  -4.4  24.1  195   9  5   7.0   3.8 |  -3.1  26.4  210  23 12   8.0   4.4
 13000  -3.3  26.1  190   9  4   7.1   3.9 |  -1.3  29.7  210  20 10   8.5   4.6
 12500  -2.3  27.9  190   8  4   7.1   3.9 |  -0.2  31.6  210  17  9   8.5   4.7
 12000  -1.2  29.8  185   8  4   7.5   4.1 |   1.1  34.0  210  15  8   8.3   4.6
 11500  -0.1  31.8  185   7  4   7.4   4.1 |   2.3  36.1  205  14  7   8.5   4.7
 11000   1.0  33.8  185   7  3   7.8   4.3 |   3.4  38.1  200  12  6   6.9   3.8
 10500   2.1  35.8  185   6  3   7.9   4.3 |   4.4  39.9  200  10  5   6.2   3.4
 10250   2.7  36.9  185   6  3   6.0   3.3 |   5.0  41.0  195  10  5   9.9   5.4
 10000   3.1  37.6  185   5  3   8.1   4.4 |   5.8  42.4  195   9  5  10.4   5.7
  9750   3.9  39.0  190   5  2  11.0   6.0 |   6.4  43.5  195   8  4   7.1   3.9
  9500   4.7  40.5  195   4  2  10.2   5.6 |   7.0  44.6  195   7  4   8.3   4.5
  9250   5.4  41.7  195   4  2   8.5   4.7 |   7.6  45.7  190   7  3   6.5   3.6
  9000   5.9  42.6  200   4  2   8.5   4.7 |   8.0  46.4  190   6  3   6.5   3.5
  8750   6.6  43.9  205   4  2   9.9   5.4 |   8.5  47.3  185   5  3   7.8   4.3
  8500   7.3  45.1  210   3  2   9.5   5.2 |   9.1  48.4  180   4  2   7.4   4.0
  8250   8.0  46.4  215   3  2   9.5   5.2 |   9.6  49.3  175   4  2   7.1   3.9
  8000   8.7  47.7  220   3  2   9.3   5.1 |  10.1  50.2  160   3  2   6.3   3.5
  7750   9.4  48.9  225   4  2   8.9   4.9 |  10.6  51.1  135   2  1   6.0   3.3
  7500  10.0  50.0  230   4  2   9.6   5.2 |  11.0  51.8  110   2  1   5.8   3.2
  7250  10.8  51.4  230   4  2  10.3   5.7 |  11.4  52.5  095   3  1   5.4   2.9
  7000  11.5  52.7  230   4  2  10.0   5.5 |  11.8  53.2  085   3  2   5.2   2.9
  6750  12.3  54.1  235   4  2   9.7   5.3 |  12.2  54.0  080   4  2   4.5   2.5
  6500  13.0  55.4  235   4  2  10.4   5.7 |  12.5  54.5  080   4  2   7.3   4.0
  6250  13.8  56.8  235   4  2  11.2   6.1 |  13.2  55.8  080   4  2   9.7   5.3
  6000  14.6  58.3  235   4  2  10.2   5.6 |  13.9  57.0  080   3  2   9.2   5.1
  5750  15.4  59.7  235   4  2  10.8   5.9 |  14.5  58.1  080   3  2   9.2   5.0
  5500  16.2  61.2  240   4  2  12.8   7.0 |  15.1  59.2  080   3  2   8.4   4.6
  5250  17.2  63.0  240   4  2  12.0   6.6 |  15.8  60.4  080   3  2   8.4   4.6
  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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