Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281315
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0714 MDT Sunday, August 28, 2016

This forecast is for Sunday, August 28, 2016:

If the trigger temperature of 72.3 F/22.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 671 ft/min (3.4 m/s)
   Maximum height of thermals.................. 15334 ft MSL (10495 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11690 ft MSL (6851 ft AGL)
Thermal soaring outlook for Monday 08/29....... Good

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

Remarks...

Sunrise/Sunset.................... 06:39:42 / 19:51:16 MDT
Total possible sunshine........... 13 hr 11 min 34 sec (791 min 34 sec)
Altitude of sun at 13:15:04 MDT... 60.22 degrees

Upper air data from rawinsonde observation taken on 08/28/2016 at 0600 MDT

Freezing level.................. 13927 ft MSL (9088 ft AGL)
Convective condensation level... 13055 ft MSL (8216 ft AGL)
Lifted condensation level....... 13764 ft MSL (8924 ft AGL)
Lifted index.................... -3.1
K index......................... +26.3

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -60.9 -77.6   245   28   14   3.6   1.9   95.1 203.2    38.5      M    M
 45000  -58.4 -73.1   220   34   18   1.7   0.9   74.9 166.9    28.8      M    M
 40000  -56.7 -70.1   205   34   18  -1.0  -0.5   54.5 130.0    17.3      M    M
 38000  -53.9 -65.0   205   25   13   7.3   4.0   49.9 121.8    14.6      M    M
 36000  -48.9 -56.0   215   13    7   7.3   4.0   47.5 117.5    13.4      M    M
 34000  -44.5 -48.1   205   12    6   6.1   3.3   45.5 113.9    12.3      M    M
 32000  -40.3 -40.5   160    6    3   4.2   2.3   43.2 109.8    11.0      M    M
 30000  -36.2 -33.2   095   10    5   9.4   5.2   40.9 105.6     9.5      M    M
 29000  -33.6 -28.5   095   10    5   8.5   4.7   40.5 104.8     9.2      M    M
 28000  -31.0 -23.8   100   10    5   9.4   5.2   40.0 104.0     9.0      M    M
 27000  -27.6 -17.7   100   10    5   8.2   4.5   40.8 105.4     9.6      M    M
 26000  -25.1 -13.2   105   10    5   9.8   5.4   40.2 104.4     9.3      M    M
 25000  -22.6  -8.7   105   10    5   6.7   3.7   39.8 103.6     9.0      M    M
 24000  -20.6  -5.1   105   10    5   6.7   3.7   38.6 101.5     8.1      M    M
 23000  -18.6  -1.5   110   10    5   6.5   3.6   37.5  99.4     7.2      M    M
 22000  -16.2   2.8   115   10    5  12.9   7.1   36.9  98.4     6.8      M    M
 21000  -14.3   6.3   125   10    5   2.2   1.2   35.7  96.3     5.8      M    M
 20000  -12.8   9.0   130   10    5   6.9   3.8   34.2  93.5     4.5      M    M
 19500  -11.8  10.8   130    9    4   7.0   3.8   33.7  92.6     4.1      M    M
 19000  -10.3  13.5   130    7    3   6.6   3.6   32.9  91.2     3.4      M    M
 18500   -9.3  15.3   120    6    3   4.1   2.3   32.4  90.3     3.0      M    M
 18000   -9.0  15.8   105    6    3   1.2   0.7   31.0  87.8     1.8      M    M
 17500   -8.2  17.2   095    6    3   9.1   5.0   30.2  86.3     1.1      M    M
 17000   -7.0  19.4   085    7    4   8.3   4.6   29.9  85.9     0.9      M    M
 16500   -5.7  21.7   075    7    4   8.2   4.5   29.7  85.5     0.7      M    M
 16000   -4.5  23.9   070    8    4   7.9   4.3   29.4  85.0     0.5      M    M
 15500   -3.4  25.9   065    8    4   6.9   3.8   29.1  84.3     0.1      M    M
 15000   -2.6  27.3   060    8    4   6.1   3.3   28.4  83.2    -0.5    840  4.3
 14500   -1.6  29.1   055    8    4   8.8   4.8   28.0  82.5    -0.9    793  4.0
 14000   -0.1  31.8   050    8    4   9.2   5.0   28.0  82.4    -0.9    734  3.7
 13500    1.2  34.2   040    6    3   8.0   4.4   27.8  82.0    -1.2    683  3.5
 13000    2.3  36.1   030    5    3   8.2   4.5   27.5  81.4    -1.5    633  3.2
 12500    3.3  37.9   010    4    2   5.9   3.2   27.1  80.7    -1.9    588  3.0
 12000    4.1  39.4   345    4    2   6.1   3.4   26.5  79.6    -2.6    550  2.8
 11500    4.9  40.8   325    3    2   6.1   3.3   25.8  78.5    -3.3    510  2.6
 11000    5.8  42.4   295    3    1   6.0   3.3   25.3  77.5    -3.9    470  2.4
 10500    6.8  44.2   265    3    1   7.8   4.3   24.8  76.7    -4.4    425  2.2
 10250    7.3  45.1   265    4    2   7.5   4.1   24.7  76.4    -4.6    401  2.0
 10000    7.9  46.2   270    5    3   7.5   4.1   24.5  76.0    -4.8    378  1.9
  9750    8.4  47.1   275    7    3   7.5   4.1   24.3  75.7    -5.0    354  1.8
  9500    9.0  48.2   275    8    4   7.6   4.1   24.1  75.4    -5.2    330  1.7
  9250    9.5  49.1   280    9    5   7.6   4.1   24.0  75.1    -5.4    307  1.6
  9000   10.0  50.0   280   11    6   7.6   4.1   23.8  74.8    -5.6    283  1.4
  8750   10.6  51.1   280   10    5   7.6   4.2   23.6  74.5    -5.8    260  1.3
  8500   11.1  52.0   285   10    5   7.5   4.1   23.5  74.2    -6.0    236  1.2
  8250   11.7  53.1   285    9    5   8.0   4.4   23.3  73.9    -6.2    212  1.1
  8000   12.3  54.1   290    8    4   8.5   4.7   23.2  73.8    -6.3    186  0.9
  7750   12.9  55.2   295    7    4   8.4   4.6   23.1  73.6    -6.4    160  0.8
  7500   13.6  56.5   300    6    3   8.4   4.6   23.0  73.4    -6.5    133  0.7
  7250   14.2  57.6   305    4    2   8.4   4.6   22.9  73.2    -6.6    107  0.5
  7000   14.8  58.6   320    3    2   8.3   4.6   22.8  73.0    -6.7     81  0.4
  6750   15.4  59.7   350    2    1   8.7   4.8   22.7  72.8    -6.8     54  0.3
  6500   16.1  61.0   065    2    1   7.4   4.1   22.6  72.6    -7.0     28  0.1
  6250   16.5  61.7   095    3    2   3.7   2.0   22.3  72.1    -7.3      8  0.0
  6000   16.7  62.1   105    5    3   2.2   1.2   21.7  71.1    -7.9      M    M
  5750   16.9  62.4   110    6    3   2.6   1.4   21.2  70.1    -8.4      M    M
  5500   17.0  62.6   115    6    3   2.3   1.3   20.6  69.1    -9.0      M    M
  5250   17.2  63.0   125    6    3   3.2   1.7   20.1  68.1    -9.6      M    M
  5000   17.4  63.3   130    6    3   0.1   0.0   19.5  67.1   -10.1      M    M

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

           08/28/2016 at 0900 MDT          |       08/28/2016 at 1200 MDT
                                           |
K index... +28.2  LI... +272.0             | K index... +25.0  LI... +271.9
CAPE... +178.2  CIN... -25.1               | CAPE... +211.6  CIN... -20.8
                                           |
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 -59.3 -74.7  225  24 12   0.9   0.5 | -59.4 -74.9  215  24 12   1.5   0.8
 45000 -58.0 -72.4  215  26 13   0.8   0.5 | -57.5 -71.5  205  19 10   0.4   0.2
 40000 -56.3 -69.3  190  19 10   6.4   3.5 | -56.6 -69.9  145   8  4   5.8   3.2
 38000 -52.7 -62.9  175  15  8   5.9   3.2 | -53.2 -63.8  120  11  6   5.7   3.1
 36000 -49.2 -56.6  150  14  7   5.9   3.3 | -49.8 -57.6  110  14  7   5.7   3.1
 34000 -44.6 -48.3  130  16  8   8.3   4.6 | -45.3 -49.5  095  17  9   8.1   4.5
 32000 -39.6 -39.3  120  20 10   8.3   4.6 | -39.9 -39.8  085  19 10   8.0   4.4
 30000 -34.9 -30.8  110  20 10   7.7   4.2 | -34.5 -30.1  080  16  8   9.3   5.1
 29000 -32.6 -26.7  110  19 10   7.7   4.2 | -31.7 -25.1  080  13  7   9.3   5.1
 28000 -30.3 -22.5  105  19 10   7.8   4.3 | -28.9 -20.0  075  11  6   8.3   4.6
 27000 -27.9 -18.2  105  16  8   7.9   4.3 | -26.8 -16.2  075   9  5   7.1   3.9
 26000 -25.6 -14.1  110  14  7   7.9   4.3 | -24.7 -12.5  075   7  4   7.1   3.9
 25000 -23.3  -9.9  110  12  6   7.9   4.3 | -22.6  -8.7  075   5  3   7.1   3.9
 24000 -21.0  -5.8  115  10  5   7.4   4.0 | -20.5  -4.9  080   4  2   7.0   3.8
 23000 -18.8  -1.8  115   8  4   7.4   4.0 | -18.5  -1.3  085   3  1   7.0   3.8
 22000 -16.1   3.0  120   6  3   7.2   3.9 | -16.4   2.5  105   2  1   7.0   3.8
 21000 -14.1   6.6  115   5  2   6.9   3.8 | -14.3   6.3  065   1  1   7.1   3.9
 20000 -12.0  10.4  110   4  2   7.0   3.8 | -12.2  10.0  030   2  1   7.2   3.9
 19500 -11.0  12.2  105   3  2   7.0   3.8 | -11.2  11.8  025   3  2   7.2   4.0
 19000 -10.1  13.8  100   3  1   6.1   3.3 | -10.2  13.6  020   4  2   6.4   3.5
 18500  -9.2  15.4  090   2  1   6.2   3.4 |  -9.3  15.3  025   5  3   6.3   3.5
 18000  -8.3  17.1  075   2  1   6.3   3.5 |  -8.0  17.6  025   8  4   5.9   3.2
 17500  -7.4  18.7  065   3  1   6.4   3.5 |  -7.1  19.2  030   9  5   5.8   3.2
 17000  -6.5  20.3  055   3  2   6.4   3.5 |  -6.3  20.7  030  11  6   5.7   3.1
 16500  -5.6  21.9  055   4  2   6.1   3.4 |  -5.5  22.1  035  12  6   5.5   3.0
 16000  -4.7  23.5  050   6  3   6.2   3.4 |  -4.7  23.5  035  14  7   5.4   3.0
 15500  -3.8  25.2  050   7  4   6.1   3.3 |  -3.8  25.2  040  15  8   6.5   3.6
 15000  -2.9  26.8  055   7  4   6.1   3.3 |  -2.9  26.8  040  15  8   6.4   3.5
 14500  -2.0  28.4  055   7  4   6.5   3.6 |  -1.9  28.6  040  15  8   6.8   3.7
 14000  -1.0  30.2  060   6  3   6.8   3.7 |  -0.9  30.4  040  15  8   6.9   3.8
 13500  -0.0  32.0  065   4  2   6.9   3.8 |   0.1  32.2  040  15  7   7.2   4.0
 13000   1.0  33.8  075   3  1   7.0   3.8 |   1.2  34.2  045  13  7   7.5   4.1
 12500   2.0  35.6  110   2  1   7.0   3.9 |   2.3  36.1  045  12  6   7.4   4.1
 12000   3.1  37.6  170   1  1   7.1   3.9 |   3.3  37.9  050  10  5   7.3   4.0
 11500   4.1  39.4  205   2  1   7.1   3.9 |   4.4  39.9  055   8  4   7.4   4.1
 11000   5.2  41.4  210   3  1   7.5   4.1 |   5.5  41.9  065   7  3   7.5   4.1
 10500   6.2  43.2  220   3  1   7.7   4.2 |   6.7  44.1  075   5  3   6.6   3.6
 10250   6.8  44.2  215   3  1   9.2   5.0 |   7.1  44.8  080   5  2   6.3   3.5
 10000   7.5  45.5  210   2  1  10.7   5.9 |   7.6  45.7  085   4  2   8.2   4.5
  9750   8.3  46.9  200   2  1  11.7   6.4 |   8.2  46.8  095   4  2   8.6   4.7
  9500   9.1  48.4  190   2  1   9.8   5.4 |   8.8  47.8  100   4  2   8.2   4.5
  9250   9.6  49.3  175   2  1   7.2   4.0 |   9.4  48.9  110   4  2   7.6   4.2
  9000  10.2  50.4  165   3  2   7.5   4.1 |  10.0  50.0  115   4  2   8.3   4.5
  8750  10.7  51.3  160   4  2   8.1   4.5 |  10.6  51.1  120   5  3   8.8   4.8
  8500  11.3  52.3  155   5  3   7.1   3.9 |  11.2  52.2  120   6  3   8.3   4.5
  8250  11.8  53.2  150   6  3   6.1   3.4 |  11.8  53.2  120   6  3   7.9   4.4
  8000  12.3  54.1  150   7  4   6.3   3.5 |  12.3  54.1  120   7  4   8.3   4.6
  7750  12.7  54.9  150   8  4   5.9   3.2 |  12.9  55.2  120   8  4   8.9   4.9
  7500  13.2  55.8  150   8  4   5.3   2.9 |  13.6  56.5  115   8  4   9.0   4.9
  7250  13.5  56.3  145   8  4   5.1   2.8 |  14.2  57.6  115   9  4   8.9   4.9
  7000  13.9  57.0  145   8  4   5.3   2.9 |  14.8  58.6  110   9  5   8.8   4.8
  6750  14.3  57.7  140   8  4   5.4   3.0 |  15.4  59.7  105   9  5   9.6   5.3
  6500  14.7  58.5  140   8  4   5.2   2.8 |  16.2  61.2  105   9  5  10.5   5.7
  6250  15.0  59.0  140   7  4   4.7   2.6 |  16.9  62.4  105   9  5  10.2   5.6
  6000  15.3  59.5  135   6  3   5.9   3.2 |  17.7  63.9  105   9  5  10.5   5.8
  5750  15.9  60.6  130   6  3  12.3   6.7 |  18.6  65.5  105   9  5  16.8   9.2
  5500  17.1  62.8  130   5  3  19.6  10.8 |  20.3  68.5  100   9  4  26.3  14.5
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/28/2016 at 1500 MDT          |       08/28/2016 at 1800 MDT
                                           |
K index... +24.8  LI... +273.7             | K index... +23.6  LI... +273.0
CAPE... 0.0  CIN... -89.4                  | CAPE... +26.0  CIN... -48.7
                                           |
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 -59.5 -75.1  220  22 12   1.6   0.9 | -59.6 -75.3  230  21 11   1.3   0.7
 45000 -57.5 -71.5  205  13  7   0.2   0.1 | -57.9 -72.2  210  11  6   0.5   0.3
 40000 -56.8 -70.2  070  12  6   6.1   3.4 | -56.7 -70.1  080  14  7   6.5   3.6
 38000 -53.3 -63.9  080  15  8   5.8   3.2 | -53.1 -63.6  075  19 10   6.0   3.3
 36000 -49.8 -57.6  085  18  9   5.9   3.2 | -49.5 -57.1  070  24 13   6.0   3.3
 34000 -45.2 -49.4  080  17  9   8.4   4.6 | -44.8 -48.6  065  24 12   8.6   4.7
 32000 -39.5 -39.1  060  14  7   8.3   4.5 | -39.0 -38.2  060  22 11   8.5   4.7
 30000 -34.1 -29.4  055  12  6   9.2   5.0 | -34.0 -29.2  050  18  9   8.4   4.6
 29000 -31.4 -24.5  050  11  6   9.2   5.1 | -31.6 -24.9  050  16  8   8.4   4.6
 28000 -28.6 -19.5  050  10  5   8.4   4.6 | -29.1 -20.4  045  14  7   8.3   4.6
 27000 -26.4 -15.5  045   8  4   7.5   4.1 | -26.6 -15.9  045  12  6   8.3   4.5
 26000 -24.2 -11.6  040   7  4   7.6   4.1 | -24.2 -11.6  045  10  5   8.3   4.6
 25000 -21.9  -7.4  035   6  3   7.7   4.2 | -21.7  -7.1  040   8  4   8.5   4.7
 24000 -20.0  -4.0  035   4  2   6.3   3.5 | -19.7  -3.5  040   6  3   6.6   3.6
 23000 -18.1  -0.6  040   3  1   6.3   3.5 | -17.7   0.1  040   4  2   6.6   3.6
 22000 -16.2   2.8  060   1  1   6.4   3.5 | -15.8   3.6  030   2  1   6.7   3.7
 21000 -13.9   7.0  045   1  1   8.0   4.4 | -13.6   7.5  015   2  1   7.3   4.0
 20000 -11.6  11.1  035   2  1   8.0   4.4 | -11.4  11.5  010   2  1   7.4   4.0
 19500 -10.4  13.3  030   2  1   8.1   4.4 | -10.4  13.3  010   3  1   7.4   4.1
 19000  -8.8  16.2  040   3  2   6.7   3.7 |  -8.8  16.2  020   4  2   6.7   3.7
 18500  -7.9  17.8  040   5  3   6.8   3.7 |  -7.9  17.8  030   6  3   6.8   3.7
 18000  -6.9  19.6  045   7  4   6.1   3.3 |  -6.9  19.6  035   8  4   6.3   3.4
 17500  -6.1  21.0  045  10  5   6.0   3.3 |  -6.0  21.2  040  10  5   6.2   3.4
 17000  -5.2  22.6  045  12  6   5.4   3.0 |  -5.2  22.6  040  12  6   6.4   3.5
 16500  -4.6  23.7  045  14  7   3.7   2.0 |  -4.1  24.6  040  13  7   7.1   3.9
 16000  -4.1  24.6  045  17  9   3.3   1.8 |  -3.1  26.4  040  14  7   7.1   3.9
 15500  -3.2  26.2  045  18  9   8.2   4.5 |  -2.1  28.2  040  15  8   6.3   3.5
 15000  -2.1  28.2  040  19 10   7.8   4.3 |  -1.2  29.8  040  16  8   6.3   3.5
 14500  -1.0  30.2  040  20 10   7.4   4.1 |  -0.2  31.6  040  17  9   7.8   4.3
 14000   0.1  32.2  040  20 10   7.4   4.0 |   1.0  33.8  045  17  9   8.2   4.5
 13500   1.2  34.2  040  20 10   7.4   4.1 |   2.2  36.0  045  18  9   8.2   4.5
 13000   2.3  36.1  045  19 10   7.5   4.1 |   3.4  38.1  050  17  9   8.2   4.5
 12500   3.4  38.1  045  19 10   8.1   4.4 |   4.6  40.3  050  17  9   8.3   4.6
 12000   4.7  40.5  050  18  9   8.9   4.9 |   5.9  42.6  055  17  9   8.5   4.6
 11500   6.0  42.8  050  16  8   8.8   4.8 |   7.1  44.8  055  17  9   8.5   4.7
 11000   7.3  45.1  055  15  8   8.6   4.7 |   8.4  47.1  055  17  9   8.4   4.6
 10500   8.6  47.5  055  14  7   7.1   3.9 |   9.7  49.5  055  17  9   5.2   2.8
 10250   9.0  48.2  055  13  7   6.6   3.6 |   9.9  49.8  060  17  9   5.6   3.1
 10000   9.6  49.3  055  13  6   8.8   4.8 |  10.6  51.1  060  17  9  11.0   6.0
  9750  10.2  50.4  060  12  6   9.3   5.1 |  11.4  52.5  060  17  9  11.1   6.1
  9500  10.9  51.6  060  11  6   7.9   4.3 |  12.2  54.0  060  16  8   8.9   4.9
  9250  11.4  52.5  060  11  5   6.1   3.4 |  12.7  54.9  060  16  8   5.7   3.1
  9000  11.9  53.4  065  10  5   7.3   4.0 |  13.1  55.6  060  16  8   8.0   4.4
  8750  12.5  54.5  065   9  5   8.3   4.6 |  13.8  56.8  060  15  8  10.1   5.6
  8500  13.1  55.6  070   9  4   7.3   4.0 |  14.5  58.1  055  14  7   8.1   4.4
  8250  13.6  56.5  070   8  4   6.7   3.7 |  15.0  59.0  055  13  7   6.4   3.5
  8000  14.0  57.2  075   8  4   6.8   3.7 |  15.5  59.9  055  11  6   7.1   3.9
  7750  14.5  58.1  080   7  4   6.9   3.8 |  16.0  60.8  055  10  5   7.6   4.1
  7500  15.1  59.2  080   7  3   7.7   4.2 |  16.5  61.7  055   8  4   8.1   4.4
  7250  15.6  60.1  085   6  3   8.1   4.5 |  17.1  62.8  055   8  4   8.4   4.6
  7000  16.2  61.2  085   6  3   8.1   4.4 |  17.7  63.9  055   7  4   8.1   4.5
  6750  16.7  62.1  085   5  3   9.6   5.3 |  18.3  64.9  055   7  3   8.6   4.7
  6500  17.5  63.5  085   5  2  10.8   5.9 |  19.0  66.2  055   6  3   9.9   5.4
  6250  18.3  64.9  080   5  2  10.7   5.9 |  19.7  67.5  055   6  3   9.8   5.4
  6000  19.1  66.4  080   5  2  10.4   5.7 |  20.5  68.9  055   5  3  10.9   6.0
  5750  20.0  68.0  080   5  2  15.9   8.7 |  21.4  70.5  055   5  3  14.3   7.8
  5500  21.5  70.7  080   4  2  25.9  14.2 |  22.6  72.7  055   5  3  16.4   9.0
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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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