Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281237
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0637 MDT Saturday, May 28, 2016

This forecast is for Saturday, May 28, 2016:

If the trigger temperature of 64.4 F/18.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 982 ft/min (5.0 m/s)
   Maximum height of thermals.................. 18134 ft MSL (13295 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14915 ft MSL (10076 ft AGL)
Thermal soaring outlook for Sunday 05/29....... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:51:46 / 20:31:04 MDT
Total possible sunshine........... 14 hr 39 min 18 sec (879 min 18 sec)
Altitude of sun at 13:11:37 MDT... 72.48 degrees

Upper air data from rawinsonde observation taken on 05/28/2016 at 0600 MDT

Freezing level.................. 11211 ft MSL (6372 ft AGL)
Convective condensation level... 12480 ft MSL (7641 ft AGL)
Lifted condensation level....... 14823 ft MSL (9984 ft AGL)
Lifted index.................... -3.6
K index......................... +22.1

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  -57.1 -70.8   270   26   13  -5.9  -3.3  105.3 221.6    45.9      M    M
 45000  -55.9 -68.6   255   30   16   0.8   0.4   82.6 180.7    35.2      M    M
 40000  -59.9 -75.8   270   37   19  -3.8  -2.1   53.2 127.8    18.4      M    M
 38000  -59.8 -75.6   270   41   21   7.0   3.9   44.3 111.8    13.0      M    M
 36000  -55.6 -68.1   275   36   19   7.0   3.8   41.9 107.4    11.7      M    M
 34000  -51.3 -60.3   275   32   17   4.9   2.7   38.8 101.8     9.8      M    M
 32000  -47.2 -53.0   270   30   15   7.0   3.8   36.2  97.1     8.2      M    M
 30000  -43.0 -45.4   260   23   12   7.3   4.0   34.2  93.5     6.9      M    M
 29000  -40.8 -41.4   260   22   11   7.8   4.3   33.2  91.8     6.2      M    M
 28000  -38.3 -36.9   260   21   11   8.4   4.6   32.8  91.0     6.0      M    M
 27000  -35.7 -32.3   265   19   10   8.4   4.6   32.1  89.8     5.5      M    M
 26000  -33.2 -27.8   270   17    9   8.4   4.6   31.6  88.9     5.2      M    M
 25000  -30.7 -23.3   280   15    8   8.4   4.6   31.2  88.2     5.0      M    M
 24000  -28.1 -18.6   290   12    6   8.7   4.8   30.7  87.2     4.6      M    M
 23000  -26.1 -15.0   290   14    7   6.2   3.4   29.6  85.3     3.7      M    M
 22000  -23.8 -10.8   290   16    8   7.5   4.1   28.9  84.0     3.1      M    M
 21000  -21.7  -7.1   280   15    8   6.6   3.6   27.8  82.0     2.3      M    M
 20000  -19.6  -3.3   265   15    8   7.7   4.2   26.9  80.4     1.5      M    M
 19500  -18.5  -1.3   270   16    8   7.6   4.2   26.5  79.7     1.2      M    M
 19000  -16.7   1.9   275   17    9   8.4   4.6   26.1  79.0     0.8      M    M
 18500  -15.7   3.7   280   17    9   5.4   3.0   25.6  78.0     0.3      M    M
 18000  -14.9   5.2   280   18    9   5.4   2.9   24.8  76.7    -0.3   1163  5.9
 17500  -14.0   6.8   285   19   10   8.5   4.7   24.3  75.7    -0.9   1120  5.7
 17000  -12.6   9.3   290   19   10   9.1   5.0   24.1  75.5    -1.0   1064  5.4
 16500  -11.2  11.8   290   20   10   9.2   5.0   24.1  75.3    -1.1   1009  5.1
 16000  -10.2  13.6   295   21   11   5.0   2.7   23.6  74.4    -1.5    964  4.9
 15500   -9.5  14.9   295   23   12   5.4   2.9   22.8  73.0    -2.3    927  4.7
 15000   -8.7  16.3   295   24   12   5.7   3.1   22.1  71.7    -3.0    889  4.5
 14500   -7.7  18.1   295   20   10   7.8   4.3   21.6  70.9    -3.4    843  4.3
 14000   -6.5  20.3   290   17    9   7.5   4.1   21.3  70.3    -3.7    794  4.0
 13500   -5.5  22.1   290   16    8   6.0   3.3   20.7  69.3    -4.2    749  3.8
 13000   -4.7  23.5   285   14    7   5.9   3.3   20.1  68.3    -4.9    709  3.6
 12500   -3.6  25.5   285   13    7   9.8   5.4   19.9  67.7    -5.3    660  3.4
 12000   -2.2  28.0   280   12    6   9.4   5.2   19.8  67.7    -5.3    604  3.1
 11500   -0.8  30.6   280   11    5   9.4   5.2   19.7  67.5    -5.5    548  2.8
 11000    0.6  33.1   280    9    5   9.4   5.2   19.7  67.4    -5.6    491  2.5
 10500    2.0  35.6   280    8    4   9.4   5.2   19.6  67.3    -5.7    435  2.2
 10250    2.7  36.9   280    7    4   9.2   5.1   19.6  67.3    -5.7    407  2.1
 10000    3.3  37.9   280    7    3   8.6   4.7   19.5  67.1    -5.8    380  1.9
  9750    3.9  39.0   280    6    3   8.7   4.8   19.4  67.0    -6.0    354  1.8
  9500    4.6  40.3   280    5    3   7.8   4.3   19.3  66.8    -6.1    328  1.7
  9250    5.1  41.2   275    5    2   6.8   3.8   19.1  66.4    -6.3    305  1.6
  9000    5.6  42.1   275    4    2   7.0   3.9   18.9  66.1    -6.5    282  1.4
  8750    6.1  43.0   250    3    1   7.0   3.8   18.7  65.7    -6.8    260  1.3
  8500    6.6  43.9   200    3    1   7.0   3.8   18.5  65.3    -7.0    237  1.2
  8250    7.1  44.8   170    4    2   7.1   3.9   18.3  64.9    -7.3    214  1.1
  8000    7.6  45.7   155    6    3   6.7   3.7   18.1  64.5    -7.5    192  1.0
  7750    8.0  46.4   155    8    4   3.1   1.7   17.7  63.9    -7.9    172  0.9
  7500    8.1  46.6   150   11    5   0.8   0.5   17.1  62.7    -8.5    162  0.8
  7250    8.2  46.8   150   13    7   1.5   0.8   16.4  61.5    -9.2    152  0.8
  7000    8.3  46.9   150   15    8   1.2   0.7   15.8  60.4    -9.8    142  0.7
  6750    8.4  47.1   145   15    8   1.5   0.8   15.1  59.2   -10.5    132  0.7
  6500    8.5  47.3   140   14    7   0.6   0.3   14.5  58.1   -11.2    122  0.6
  6250    8.6  47.5   130   13    7   3.8   2.1   13.8  56.9   -11.8    112  0.6
  6000    9.1  48.4   125   12    6   9.2   5.1   13.6  56.6   -12.1     89  0.5
  5750    9.8  49.6   120   11    6   9.1   5.0   13.6  56.5   -12.1     61  0.3
  5500   10.5  50.9   115    9    5  11.6   6.4   13.6  56.5   -12.2     32  0.2
  5250   11.2  52.2   105    8    4   1.8   1.0   13.6  56.5   -12.3      4  0.0
  5000   10.3  50.5   100    7    4 -24.7 -13.5   12.0  53.6   -13.9     23  0.1

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

           05/28/2016 at 0900 MDT          |       05/28/2016 at 1200 MDT
                                           |
K index... +19.5  LI... +273.2             | K index... +17.8  LI... +271.5
CAPE... +0.8  CIN... -19.6                 | CAPE... +129.8  CIN... -33.0
                                           |
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 -56.9 -70.4  240  19 10   0.3   0.2 | -57.4 -71.3  245  23 12   0.6   0.3
 45000 -56.6 -69.9  265  29 15  -2.0  -1.1 | -56.6 -69.9  260  31 16  -2.4  -1.3
 40000 -60.0 -76.0  275  37 19  -2.3  -1.3 | -60.6 -77.1  265  43 22  -2.3  -1.3
 38000 -58.1 -72.6  275  39 20   6.0   3.3 | -58.4 -73.1  270  44 23   6.2   3.4
 36000 -54.5 -66.1  280  39 20   6.0   3.3 | -54.7 -66.5  270  45 23   6.2   3.4
 34000 -50.6 -59.1  280  38 19   7.4   4.1 | -50.7 -59.3  275  44 23   7.3   4.0
 32000 -46.2 -51.2  280  34 18   7.4   4.1 | -46.3 -51.3  275  40 21   7.3   4.0
 30000 -41.8 -43.2  285  30 15   7.1   3.9 | -41.9 -43.4  280  35 18   7.7   4.2
 29000 -39.7 -39.5  285  27 14   7.1   3.9 | -39.6 -39.3  280  32 17   7.7   4.2
 28000 -37.6 -35.7  280  24 12   7.1   3.9 | -37.2 -35.0  285  29 15   7.7   4.2
 27000 -35.4 -31.7  280  21 11   7.4   4.1 | -34.3 -29.7  285  25 13   8.1   4.5
 26000 -32.6 -26.7  280  19 10   7.5   4.1 | -31.9 -25.4  285  23 12   8.1   4.5
 25000 -30.4 -22.7  280  17  9   7.5   4.1 | -29.4 -20.9  285  21 11   8.1   4.5
 24000 -28.1 -18.6  280  16  8   8.0   4.4 | -27.1 -16.8  285  19 10   7.2   3.9
 23000 -25.8 -14.4  280  16  8   8.0   4.4 | -24.9 -12.8  285  18  9   7.3   4.0
 22000 -23.4 -10.1  280  15  8   8.0   4.4 | -22.7  -8.9  280  17  9   7.3   4.0
 21000 -21.1  -6.0  285  15  8   7.1   3.9 | -20.6  -5.1  280  17  9   6.8   3.7
 20000 -19.0  -2.2  290  16  8   7.2   3.9 | -18.6  -1.5  280  17  9   6.8   3.7
 19500 -18.0  -0.4  290  16  8   7.2   3.9 | -17.6   0.3  280  17  9   6.8   3.8
 19000 -16.9   1.6  290  16  8   7.3   4.0 | -16.6   2.1  285  18  9   6.9   3.8
 18500 -15.9   3.4  295  16  8   6.2   3.4 | -15.6   3.9  285  18  9   7.5   4.1
 18000 -15.0   5.0  295  17  9   6.4   3.5 | -14.5   5.9  285  18  9   7.5   4.1
 17500 -14.0   6.8  295  17  9   7.1   3.9 | -13.4   7.9  290  17  9   7.3   4.0
 17000 -12.9   8.8  300  17  9   7.6   4.2 | -12.3   9.9  290  17  9   7.2   4.0
 16500 -11.7  10.9  300  17  8   7.6   4.2 | -11.3  11.7  290  16  8   7.3   4.0
 16000 -10.6  12.9  300  16  8   7.3   4.0 | -10.2  13.6  290  15  8   7.6   4.1
 15500  -9.6  14.7  305  16  8   7.4   4.0 |  -9.0  15.8  290  15  7   7.5   4.1
 15000  -8.5  16.7  305  16  8   7.4   4.1 |  -7.9  17.8  290  14  7   7.6   4.2
 14500  -7.4  18.7  305  15  8   7.4   4.1 |  -6.8  19.8  290  13  7   7.6   4.2
 14000  -6.3  20.7  310  15  8   7.9   4.3 |  -5.7  21.7  290  13  7   8.0   4.4
 13500  -5.2  22.6  305  15  8   8.1   4.4 |  -4.5  23.9  285  12  6   8.1   4.5
 13000  -3.4  25.9  295  15  8   8.4   4.6 |  -2.6  27.3  285  11  6   8.5   4.7
 12500  -2.2  28.0  295  15  8   8.4   4.6 |  -1.4  29.5  285  11  5   8.5   4.7
 12000  -1.0  30.2  290  14  7   8.3   4.5 |  -0.1  31.8  285  11  5   8.6   4.7
 11500   0.2  32.4  285  13  7   8.4   4.6 |   1.1  34.0  285  11  6   8.6   4.7
 11000   1.4  34.5  280  12  6   7.5   4.1 |   2.4  36.3  285  11  6   8.5   4.7
 10500   2.5  36.5  275  10  5   8.2   4.5 |   3.6  38.5  285  11  5   7.2   3.9
 10250   3.0  37.4  270  10  5   4.9   2.7 |   4.1  39.4  285  10  5   6.4   3.5
 10000   3.3  37.9  265   9  5   5.9   3.2 |   4.6  40.3  280  10  5   9.2   5.0
  9750   3.9  39.0  260   8  4   9.8   5.4 |   5.4  41.7  280   9  5  10.0   5.5
  9500   4.6  40.3  255   8  4   8.9   4.9 |   6.1  43.0  280   9  5   9.6   5.3
  9250   5.2  41.4  250   7  4   7.4   4.1 |   6.7  44.1  275   8  4   7.5   4.1
  9000   5.6  42.1  245   6  3   6.6   3.6 |   7.2  45.0  275   7  4   6.8   3.8
  8750   6.2  43.2  235   6  3   7.5   4.1 |   7.7  45.9  270   6  3   7.9   4.3
  8500   6.7  44.1  225   5  3   7.1   3.9 |   8.3  46.9  265   5  2   7.4   4.1
  8250   7.2  45.0  210   5  2   6.8   3.8 |   8.7  47.7  260   4  2   6.4   3.5
  8000   7.7  45.9  200   5  2   6.5   3.6 |   9.2  48.6  250   3  1   7.3   4.0
  7750   8.2  46.8  190   5  3   6.8   3.7 |   9.7  49.5  245   2  1   8.2   4.5
  7500   8.7  47.7  180   6  3   5.7   3.1 |  10.3  50.5  235   2  1   9.3   5.1
  7250   9.0  48.2  175   6  3   4.3   2.4 |  11.1  52.0  230   2  1  11.0   6.0
  7000   9.3  48.7  170   7  4   3.9   2.1 |  11.9  53.4  230   2  1  10.3   5.6
  6750   9.6  49.3  165   7  4   3.3   1.8 |  12.6  54.7  225   2  1   9.8   5.4
  6500   9.9  49.8  160   8  4   6.4   3.5 |  13.3  55.9  225   2  1  10.7   5.9
  6250  10.5  50.9  160   7  4   9.0   5.0 |  14.2  57.6  225   2  1  11.7   6.4
  6000  11.1  52.0  160   7  3   7.4   4.0 |  15.0  59.0  220   2  1  10.1   5.6
  5750  11.6  52.9  155   6  3   8.7   4.8 |  15.8  60.4  225   2  1  12.0   6.6
  5500  12.4  54.3  155   5  3  11.4   6.2 |  16.9  62.4  225   2  1  16.0   8.8
  5250  13.2  55.8  155   5  3  10.3   5.7 |  18.0  64.4  230   2  1  14.1   7.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/28/2016 at 1500 MDT          |       05/28/2016 at 1800 MDT
                                           |
K index... +19.0  LI... +272.4             | K index... +19.8  LI... +272.7
CAPE... +23.0  CIN... -48.9                | CAPE... +13.5  CIN... -21.3
                                           |
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 -57.5 -71.5  245  25 13   0.5   0.3 | -58.2 -72.8  255  29 15   0.1   0.0
 45000 -56.9 -70.4  260  37 19  -2.7  -1.5 | -58.2 -72.8  260  38 20  -2.6  -1.4
 40000 -61.0 -77.8  265  49 25  -2.3  -1.3 | -62.0 -79.6  265  44 23  -2.2  -1.2
 38000 -58.6 -73.5  265  49 25   6.6   3.6 | -59.0 -74.2  270  44 23   7.3   4.0
 36000 -54.6 -66.3  270  46 24   6.6   3.6 | -54.7 -66.5  270  44 22   7.3   4.0
 34000 -50.5 -58.9  270  44 22   7.5   4.1 | -50.2 -58.4  275  42 21   7.8   4.3
 32000 -46.0 -50.8  275  40 21   7.4   4.1 | -45.5 -49.9  275  37 19   7.8   4.3
 30000 -41.5 -42.7  275  36 18   7.9   4.3 | -40.8 -41.4  280  33 17   8.0   4.4
 29000 -39.1 -38.4  280  33 17   7.9   4.3 | -37.8 -36.0  280  30 16   8.0   4.4
 28000 -36.2 -33.2  280  29 15   7.9   4.3 | -35.4 -31.7  280  28 14   8.0   4.4
 27000 -33.8 -28.8  280  27 14   7.9   4.4 | -33.0 -27.4  280  26 13   8.0   4.4
 26000 -31.4 -24.5  280  24 12   7.9   4.4 | -30.6 -23.1  275  23 12   8.0   4.4
 25000 -29.1 -20.4  280  21 11   8.0   4.4 | -28.2 -18.8  275  21 11   8.0   4.4
 24000 -26.7 -16.1  280  20 10   7.9   4.3 | -25.8 -14.4  270  19 10   7.9   4.3
 23000 -24.3 -11.7  280  19 10   7.9   4.3 | -23.4 -10.1  270  19 10   7.9   4.3
 22000 -22.0  -7.6  280  19 10   7.9   4.3 | -21.1  -6.0  265  19 10   7.9   4.3
 21000 -19.8  -3.6  275  19 10   6.9   3.8 | -18.9  -2.0  265  20 10   6.6   3.6
 20000 -17.8  -0.0  275  19 10   6.9   3.8 | -17.0   1.4  265  22 11   6.6   3.6
 19500 -16.8   1.8  270  19 10   6.9   3.8 | -16.0   3.2  265  22 12   6.7   3.7
 19000 -15.8   3.6  270  20 10   7.0   3.8 | -15.0   5.0  265  23 12   7.0   3.8
 18500 -14.7   5.5  270  20 10   7.6   4.2 | -13.9   7.0  265  23 12   8.0   4.4
 18000 -13.6   7.5  270  20 10   7.6   4.2 | -12.8   9.0  265  23 12   7.9   4.3
 17500 -12.4   9.7  270  20 10   7.8   4.3 | -11.6  11.1  260  23 12   8.1   4.5
 17000 -11.3  11.7  270  19 10   7.9   4.3 | -10.4  13.3  260  22 11   8.2   4.5
 16500 -10.1  13.8  270  19 10   8.0   4.4 |  -9.2  15.4  260  22 11   8.3   4.6
 16000  -8.9  16.0  265  19 10   8.2   4.5 |  -7.9  17.8  260  21 11   8.6   4.7
 15500  -7.7  18.1  265  18  9   8.2   4.5 |  -6.7  19.9  255  20 10   8.7   4.7
 15000  -6.4  20.5  265  18  9   8.6   4.7 |  -5.5  22.1  255  19 10   8.2   4.5
 14500  -5.2  22.6  265  18  9   8.6   4.7 |  -4.2  24.4  255  18  9   8.3   4.5
 14000  -3.9  25.0  265  17  9   8.3   4.5 |  -3.0  26.6  255  17  9   8.5   4.7
 13500  -2.1  28.2  265  16  8   8.2   4.5 |  -1.1  30.0  255  15  8   8.5   4.7
 13000  -0.9  30.4  265  16  8   8.2   4.5 |   0.1  32.2  255  14  7   8.3   4.5
 12500   0.3  32.5  260  15  8   8.2   4.5 |   1.3  34.3  255  12  6   8.3   4.5
 12000   1.5  34.7  260  14  7   8.4   4.6 |   2.6  36.7  255  11  6   9.0   4.9
 11500   2.8  37.0  260  12  6   8.4   4.6 |   3.9  39.0  255  10  5   8.9   4.9
 11000   4.0  39.2  260  11  6   7.9   4.3 |   5.2  41.4  255   9  5   8.2   4.5
 10500   5.2  41.4  260  10  5   5.3   2.9 |   6.5  43.7  260   8  4   5.0   2.8
 10250   5.5  41.9  265   9  5   5.9   3.2 |   6.7  44.1  260   7  4   5.7   3.1
 10000   6.1  43.0  265   8  4   9.7   5.3 |   7.4  45.3  260   7  3  10.4   5.7
  9750   6.8  44.2  265   7  4   8.7   4.8 |   8.1  46.6  260   6  3   9.2   5.0
  9500   7.4  45.3  265   6  3   8.7   4.8 |   8.8  47.8  255   5  3   9.3   5.1
  9250   8.0  46.4  265   5  3   7.2   3.9 |   9.5  49.1  255   4  2   7.7   4.2
  9000   8.5  47.3  270   5  3   7.8   4.3 |  10.0  50.0  250   3  2   7.5   4.1
  8750   9.1  48.4  270   4  2   9.0   4.9 |  10.6  51.1  240   2  1   8.3   4.6
  8500   9.8  49.6  270   4  2   8.9   4.9 |  11.2  52.2  215   2  1   7.9   4.3
  8250  10.4  50.7  270   4  2   9.5   5.2 |  11.7  53.1  185   1  1   7.1   3.9
  8000  11.1  52.0  270   4  2   9.8   5.4 |  12.2  54.0  165   2  1   7.8   4.3
  7750  11.9  53.4  270   4  2   9.8   5.4 |  12.8  55.0  160   2  1   8.5   4.7
  7500  12.6  54.7  270   4  2  10.1   5.5 |  13.4  56.1  155   2  1   9.0   5.0
  7250  13.4  56.1  270   4  2  10.6   5.8 |  14.2  57.6  155   2  1  10.2   5.6
  7000  14.1  57.4  270   4  2  10.2   5.6 |  14.9  58.8  160   2  1   9.7   5.3
  6750  14.9  58.8  270   4  2   9.8   5.4 |  15.6  60.1  160   2  1   9.1   5.0
  6500  15.7  60.3  270   4  2  10.8   5.9 |  16.3  61.3  155   2  1  10.3   5.6
  6250  16.5  61.7  265   4  2  12.1   6.7 |  17.1  62.8  160   2  1  11.4   6.3
  6000  17.4  63.3  265   4  2   9.9   5.4 |  18.0  64.4  165   2  1  10.3   5.6
  5750  18.1  64.6  265   4  2  11.2   6.2 |  18.7  65.7  165   2  1   9.8   5.4
  5500  19.1  66.4  265   3  2  16.1   8.8 |  19.4  66.9  165   2  1  10.8   5.9
  5250  20.3  68.5  270   4  2  14.9   8.2 |  20.3  68.5  160   2  1  11.0   6.0
  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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