Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221231
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0631 MDT Saturday, July 22, 2017

This forecast is for Saturday, July 22, 2017:

If the trigger temperature of 80.1 F/26.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 648 ft/min (3.3 m/s)
   Maximum height of thermals.................. 15690 ft MSL (10851 ft AGL)

Forecast maximum temperature................... 95.0 F/35.5 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................. 12522 ft MSL (7682 ft AGL)
Thermal soaring outlook for Sunday 07/23....... Good

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

Remarks...

Sunrise/Sunset.................... 06:06:20 / 20:35:04 MDT
Total possible sunshine........... 14 hr 28 min 44 sec (868 min 44 sec)
Altitude of sun at 13:20:34 MDT... 70.97 degrees

Upper air data from rawinsonde observation taken on 07/22/2017 at 0600 MDT

Freezing level.................. 17123 ft MSL (12284 ft AGL)
Convective condensation level... 13784 ft MSL (8945 ft AGL)
Lifted condensation level....... 14699 ft MSL (9859 ft AGL)
Lifted index.................... -5.1
K index......................... +23.5

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  -67.5 -89.5   225   12    6   5.5   3.0   80.2 176.4    26.3      M    M
 45000  -60.1 -76.2   280   32   17   8.9   4.9   68.2 154.7    20.7      M    M
 40000  -50.2 -58.4   265   35   18   7.5   4.1   60.7 141.2    17.2      M    M
 38000  -46.2 -51.2   265   33   17   6.1   3.3   58.0 136.5    15.8      M    M
 36000  -42.7 -44.9   265   31   16   7.3   4.0   54.7 130.4    13.8      M    M
 34000  -37.2 -35.0   255   22   11   9.4   5.1   53.1 127.6    13.1      M    M
 32000  -32.4 -26.3   245   16    8   8.2   4.5   51.8 125.3    12.4      M    M
 30000  -27.7 -17.9   255    7    4   7.8   4.3   50.4 122.7    11.6      M    M
 29000  -25.4 -13.7   260    5    2   7.9   4.3   49.6 121.3    11.1      M    M
 28000  -23.1  -9.6   130    4    2   8.1   4.5   48.8 119.8    10.5      M    M
 27000  -21.4  -6.5   110   11    6   5.3   2.9   47.3 117.1     9.4      M    M
 26000  -21.1  -6.0   025   19   10   6.1   3.4   43.9 111.0     6.9      M    M
 25000  -18.1  -0.6   025   20   10   9.4   5.2   43.9 111.1     7.1      M    M
 24000  -15.4   4.3   020   20   10   9.4   5.2   43.6 110.5     6.9      M    M
 23000  -13.2   8.2   020   18    9   7.7   4.2   42.7 108.8     6.3      M    M
 22000  -11.2  11.8   025   15    8   4.5   2.5   41.5 106.7     5.4      M    M
 21000   -9.0  15.8   035   15    8   6.0   3.3   40.7 105.2     4.7      M    M
 20000   -6.5  20.3   035   19   10   8.0   4.4   40.1 104.2     4.3      M    M
 19500   -5.4  22.3   030   21   11   7.9   4.3   39.8 103.6     4.1      M    M
 19000   -4.2  24.4   025   22   11   7.1   3.9   39.4 102.8     3.7      M    M
 18500   -2.6  27.3   035   22   12   7.2   3.9   38.7 101.6     3.2      M    M
 18000   -1.6  29.1   040   22   12   7.0   3.9   38.2 100.8     2.8      M    M
 17500   -0.6  30.9   045   20   10   7.7   4.2   37.8 100.0     2.3      M    M
 17000    0.6  33.1   050   18    9   8.6   4.7   37.5  99.6     2.1      M    M
 16500    1.5  34.7   060   16    8   3.8   2.1   37.0  98.5     1.5      M    M
 16000    1.7  35.1   065   15    8   5.5   3.0   36.0  96.7     0.3      M    M
 15500    2.7  36.9   060   13    7   6.6   3.6   35.4  95.7    -0.3    825  4.2
 15000    3.6  38.5   060   12    6   6.8   3.8   34.9  94.8    -0.8    783  4.0
 14500    4.6  40.3   055   11    6   7.6   4.2   34.5  94.1    -1.2    736  3.7
 14000    5.7  42.3   050   10    5   7.6   4.2   34.2  93.5    -1.6    689  3.5
 13500    6.8  44.2   045   10    5   7.6   4.2   33.8  92.8    -2.0    641  3.3
 13000    7.9  46.2   040   10    5   6.3   3.4   33.4  92.2    -2.4    594  3.0
 12500    8.7  47.7   040   11    6   5.6   3.1   32.7  90.9    -3.1    556  2.8
 12000    9.5  49.1   035   11    6   5.6   3.1   32.1  89.7    -3.7    517  2.6
 11500   10.3  50.5   030   11    5   6.5   3.5   31.4  88.5    -4.4    479  2.4
 11000   11.5  52.7   020   10    5   8.8   4.8   31.1  88.0    -4.7    426  2.2
 10500   12.8  55.0   015   10    5   8.5   4.7   31.0  87.8    -4.8    372  1.9
 10250   13.4  56.1   015    9    5   7.5   4.1   30.9  87.5    -5.0    347  1.8
 10000   13.9  57.0   010    9    5   4.6   2.5   30.6  87.0    -5.3    327  1.7
  9750   14.0  57.2   010    8    4   2.9   1.6   30.1  86.1    -5.9    314  1.6
  9500   14.2  57.6   005    7    4   3.5   1.9   29.5  85.2    -6.4    301  1.5
  9250   14.4  57.9   005    7    3   3.3   1.8   29.1  84.3    -7.0    289  1.5
  9000   14.5  58.1   360    6    3   3.7   2.0   28.6  83.4    -7.6    276  1.4
  8750   14.8  58.6   015    7    4   4.3   2.3   28.1  82.6    -8.1    262  1.3
  8500   15.1  59.2   025    9    5   4.4   2.4   27.7  81.8    -8.5    245  1.2
  8250   15.4  59.7   035   11    5   4.4   2.4   27.3  81.1    -9.0    229  1.2
  8000   15.7  60.3   040   13    7   4.3   2.4   26.9  80.4    -9.5    213  1.1
  7750   16.0  60.8   040   11    6   4.6   2.5   26.5  79.6    -9.9    197  1.0
  7500   16.2  61.2   035    9    5   1.8   1.0   26.0  78.8   -10.4    183  0.9
  7250   16.1  61.0   035    7    4  -1.1  -0.6   25.2  77.4   -11.3    178  0.9
  7000   16.0  60.8   025    5    3   1.5   0.8   24.5  76.0   -12.1    173  0.9
  6750   16.3  61.3   020    4    2   5.8   3.2   24.0  75.2   -12.6    158  0.8
  6500   16.7  62.1   010    2    1   7.2   4.0   23.8  74.8   -12.9    136  0.7
  6250   17.2  63.0   270    1    0   6.8   3.8   23.6  74.4   -13.2    114  0.6
  6000   17.7  63.9   230    2    1   6.9   3.8   23.4  74.1   -13.4     92  0.5
  5750   18.2  64.8   225    2    1   7.0   3.8   23.2  73.7   -13.7     70  0.4
  5500   18.7  65.7   235    1    1   6.7   3.7   22.9  73.3   -14.0     48  0.2
  5250   19.2  66.6   000    0    0   7.7   4.2   22.7  72.9   -14.3     26  0.1
  5000   19.7  67.5   015    1    0   4.2   2.3   22.5  72.5   -14.5      4  0.0

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

           07/22/2017 at 0900 MDT          |       07/22/2017 at 1200 MDT
                                           |
K index... +20.9  LI... -1.5               | K index... +18.2  LI... -2.4
CAPE... +558.1  CIN... -64.7               | CAPE... +1020.6  CIN... -26.7
                                           |
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 -65.1 -85.2  280  21 11   1.8   1.0 | -65.1 -85.2  275  23 12   1.7   0.9
 45000 -59.8 -75.6  275  30 16   6.4   3.5 | -59.9 -75.8  275  32 17   6.3   3.5
 40000 -50.2 -58.4  270  35 18   6.7   3.7 | -49.8 -57.6  270  36 18   7.0   3.8
 38000 -46.2 -51.2  270  31 16   6.7   3.7 | -45.6 -50.1  270  33 17   7.0   3.8
 36000 -42.2 -44.0  270  28 14   6.8   3.7 | -41.5 -42.7  275  31 16   6.7   3.7
 34000 -37.4 -35.3  265  21 11   7.2   3.9 | -37.5 -35.5  275  23 12   6.6   3.6
 32000 -33.1 -27.6  260  14  7   8.1   4.4 | -33.5 -28.3  270  15  8   7.3   4.0
 30000 -28.6 -19.5  285   6  3   7.5   4.1 | -29.2 -20.6  290   9  5   7.3   4.0
 29000 -26.3 -15.3  335   4  2   7.5   4.1 | -27.1 -16.8  310   7  4   7.3   4.0
 28000 -24.1 -11.4  020   5  3   7.2   4.0 | -24.8 -12.6  340   6  3   8.2   4.5
 27000 -21.9  -7.4  035   6  3   7.3   4.0 | -22.4  -8.3  360   5  3   8.2   4.5
 26000 -19.6  -3.3  040   7  4   7.4   4.1 | -19.2  -2.6  030   5  2   8.3   4.5
 25000 -17.4   0.7  050   8  4   7.3   4.0 | -16.8   1.8  050   5  3   7.3   4.0
 24000 -15.2   4.6  050   9  5   7.3   4.0 | -14.6   5.7  055   6  3   7.3   4.0
 23000 -13.0   8.6  050  10  5   7.3   4.0 | -12.4   9.7  060   6  3   7.3   4.0
 22000 -10.8  12.6  050  11  6   7.2   4.0 | -10.3  13.5  065   7  3   7.2   4.0
 21000  -8.7  16.3  045  11  6   7.2   4.0 |  -8.1  17.4  060   7  4   7.2   4.0
 20000  -6.5  20.3  035  12  6   7.3   4.0 |  -6.0  21.2  055   8  4   7.2   4.0
 19500  -4.9  23.2  035  13  7   6.5   3.6 |  -4.9  23.2  055   8  4   6.8   3.7
 19000  -4.0  24.8  030  13  7   6.0   3.3 |  -4.0  24.8  050   8  4   6.0   3.3
 18500  -3.1  26.4  030  13  7   6.1   3.3 |  -3.1  26.4  050   9  5   6.1   3.3
 18000  -2.3  27.9  030  13  7   5.3   2.9 |  -2.3  27.9  045   9  5   4.6   2.5
 17500  -1.5  29.3  030  13  7   5.4   3.0 |  -1.6  29.1  045  10  5   4.6   2.5
 17000  -0.8  30.6  030  13  7   6.2   3.4 |  -1.0  30.2  045  10  5   5.1   2.8
 16500   0.2  32.4  035  12  6   6.8   3.7 |  -0.1  31.8  045  10  5   6.1   3.4
 16000   1.1  34.0  035  12  6   7.0   3.9 |   0.7  33.3  045  10  5   6.1   3.4
 15500   2.1  35.8  035  11  6   7.4   4.1 |   1.7  35.1  045  11  6   8.1   4.4
 15000   3.1  37.6  040  11  6   7.6   4.1 |   2.8  37.0  045  12  6   8.0   4.4
 14500   4.1  39.4  040  11  6   6.4   3.5 |   3.9  39.0  045  13  7   8.0   4.4
 14000   5.0  41.0  045  11  6   6.4   3.5 |   5.1  41.2  050  14  7   7.9   4.4
 13500   5.9  42.6  045  11  6   7.1   3.9 |   6.3  43.3  050  15  8   7.9   4.3
 13000   6.9  44.4  045  11  6   7.4   4.1 |   8.0  46.4  055  15  8   7.8   4.3
 12500   7.9  46.2  045  11  6   7.5   4.1 |   9.1  48.4  055  15  8   8.0   4.4
 12000   8.9  48.0  045  11  6   7.6   4.2 |  10.2  50.4  060  15  8   8.1   4.4
 11500  10.0  50.0  045  11  6   7.7   4.2 |  11.4  52.5  060  15  8   8.4   4.6
 11000  11.1  52.0  045  11  5   7.7   4.2 |  12.5  54.5  060  14  7   8.9   4.9
 10500  12.2  54.0  045  10  5   3.9   2.2 |  13.4  56.1  060  13  7   4.2   2.3
 10250  12.3  54.1  045  10  5   4.3   2.4 |  13.7  56.7  060  13  7   7.4   4.0
 10000  12.9  55.2  050  10  5  10.2   5.6 |  14.4  57.9  060  12  6  10.5   5.8
  9750  13.5  56.3  050  10  5  10.0   5.5 |  15.0  59.0  060  12  6   9.5   5.2
  9500  14.1  57.4  050  10  5   7.6   4.2 |  15.6  60.1  055  11  6   7.3   4.0
  9250  14.5  58.1  050   9  5   4.5   2.4 |  16.0  60.8  055  10  5   7.0   3.8
  9000  14.9  58.8  055   9  5   6.2   3.4 |  16.5  61.7  055  10  5   8.7   4.8
  8750  15.4  59.7  055   9  5   7.4   4.1 |  17.1  62.8  050   9  5   8.4   4.6
  8500  15.8  60.4  055   9  5   6.1   3.3 |  17.6  63.7  050   9  4   7.8   4.3
  8250  16.2  61.2  055   9  5   5.1   2.8 |  18.1  64.6  045   8  4   7.7   4.2
  8000  16.6  61.9  060   9  5   5.3   2.9 |  18.7  65.7  045   8  4   8.5   4.7
  7750  17.0  62.6  060   9  4   4.9   2.7 |  19.3  66.7  040   7  4   9.5   5.2
  7500  17.3  63.1  060   8  4   3.1   1.7 |  20.0  68.0  040   7  4   9.9   5.4
  7250  17.4  63.3  065   8  4   2.1   1.2 |  20.7  69.3  040   7  3  10.2   5.6
  7000  17.5  63.5  065   7  4   2.0   1.1 |  21.5  70.7  040   6  3   9.4   5.2
  6750  17.7  63.9  065   6  3   2.3   1.3 |  22.1  71.8  040   6  3  10.2   5.6
  6500  17.9  64.2  070   5  3   4.0   2.2 |  23.0  73.4  040   6  3  11.3   6.2
  6250  18.2  64.8  070   4  2   4.2   2.3 |  23.8  74.8  040   6  3  11.1   6.1
  6000  18.4  65.1  075   3  2   5.0   2.7 |  24.6  76.3  035   5  3  10.9   6.0
  5750  19.0  66.2  080   3  1  12.2   6.7 |  25.4  77.7  035   5  3  13.8   7.6
  5500  20.3  68.5  080   3  1  21.3  11.7 |  26.6  79.9  035   5  3  16.8   9.2
  5250     M     M    M   M  M     M     M |  27.8  82.0  035   5  3  14.5   8.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/22/2017 at 1500 MDT          |       07/22/2017 at 1800 MDT
                                           |
K index... +15.8  LI... -0.1               | K index... +20.6  LI... +0.5
CAPE... +239.7  CIN... -27.0               | CAPE... +168.9  CIN... -47.5
                                           |
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 -65.0 -85.0  270  23 12   2.0   1.1 | -64.9 -84.8  280  24 12   1.8   1.0
 45000 -59.6 -75.3  270  34 17   6.1   3.4 | -59.9 -75.8  275  37 19   5.9   3.2
 40000 -49.7 -57.5  270  43 22   7.2   3.9 | -50.6 -59.1  280  49 25   7.5   4.1
 38000 -45.4 -49.7  270  40 21   7.2   3.9 | -46.1 -51.0  275  46 23   7.5   4.1
 36000 -41.1 -42.0  270  38 19   6.9   3.8 | -41.6 -42.9  270  42 22   7.2   4.0
 34000 -37.0 -34.6  265  27 14   6.8   3.7 | -37.0 -34.6  260  33 17   6.8   3.7
 32000 -33.0 -27.4  250  17  9   7.1   3.9 | -32.9 -27.2  240  26 14   7.6   4.2
 30000 -28.8 -19.8  260  10  5   7.0   3.8 | -28.4 -19.1  235  16  8   7.6   4.2
 29000 -26.7 -16.1  270   6  3   7.0   3.8 | -26.1 -15.0  230  11  6   7.6   4.2
 28000 -24.6 -12.3  290   4  2   8.2   4.5 | -23.9 -11.0  225   7  4   7.3   4.0
 27000 -22.1  -7.8  305   3  1   8.2   4.5 | -21.6  -6.9  240   5  2   7.4   4.0
 26000 -19.1  -2.4  340   2  1   8.2   4.5 | -19.4  -2.9  280   3  1   7.4   4.1
 25000 -16.6   2.1  015   2  1   7.2   4.0 | -17.1   1.2  335   3  2   7.3   4.0
 24000 -14.5   5.9  020   3  1   7.1   3.9 | -15.0   5.0  350   5  2   7.2   4.0
 23000 -12.4   9.7  025   3  2   7.1   3.9 | -12.8   9.0  355   6  3   7.2   4.0
 22000 -10.2  13.6  030   4  2   7.4   4.0 | -10.6  12.9  360   7  4   7.9   4.3
 21000  -8.0  17.6  035   4  2   7.4   4.1 |  -8.1  17.4  355   7  3   8.1   4.4
 20000  -5.8  21.6  045   4  2   7.4   4.1 |  -5.7  21.7  350   7  3   8.0   4.4
 19500  -4.7  23.5  045   5  2   7.1   3.9 |  -4.5  23.9  345   6  3   7.6   4.2
 19000  -3.7  25.3  050   5  3   6.6   3.6 |  -3.6  25.5  350   7  3   5.8   3.2
 18500  -2.7  27.1  050   6  3   6.7   3.7 |  -2.7  27.1  355   7  4   6.0   3.3
 18000  -1.7  28.9  050   6  3   5.6   3.1 |  -1.8  28.8  005   7  4   5.8   3.2
 17500  -0.9  30.4  050   8  4   5.6   3.0 |  -1.0  30.2  020   7  4   5.9   3.2
 17000  -0.1  31.8  050   9  4   5.6   3.1 |  -0.2  31.6  030   8  4   6.2   3.4
 16500   0.7  33.3  050  10  5   5.7   3.1 |   0.7  33.3  035   9  5   7.1   3.9
 16000   1.5  34.7  050  11  5   5.8   3.2 |   1.7  35.1  040  10  5   7.1   3.9
 15500   2.4  36.3  050  11  6   7.7   4.2 |   3.4  38.1  040  11  6   8.4   4.6
 15000   3.5  38.3  050  12  6   7.7   4.2 |   4.6  40.3  040  12  6   8.5   4.6
 14500   4.6  40.3  050  13  7   8.3   4.5 |   5.8  42.4  040  12  6   8.9   4.9
 14000   5.8  42.4  050  13  7   8.5   4.7 |   7.1  44.8  040  13  7   8.9   4.9
 13500   7.0  44.6  050  14  7   8.7   4.8 |   8.4  47.1  045  13  7   9.3   5.1
 13000   8.9  48.0  050  14  7   9.0   4.9 |   9.8  49.6  045  14  7   9.3   5.1
 12500  10.1  50.2  050  14  7   8.8   4.8 |  11.1  52.0  045  14  7   9.3   5.1
 12000  11.4  52.5  050  14  7   8.8   4.8 |  12.5  54.5  045  15  8   9.3   5.1
 11500  12.6  54.7  050  14  7   8.8   4.8 |  13.8  56.8  045  15  8   9.2   5.1
 11000  13.8  56.8  050  13  7   9.3   5.1 |  15.2  59.4  045  15  8   9.2   5.0
 10500  14.8  58.6  045  12  6   5.7   3.1 |  16.5  61.7  045  15  8   5.5   3.0
 10250  15.4  59.7  045  12  6   9.5   5.2 |  16.8  62.2  050  15  7   7.2   4.0
 10000  16.1  61.0  045  11  6  11.5   6.3 |  17.6  63.7  050  14  7  11.2   6.2
  9750  16.9  62.4  045  11  6  11.1   6.1 |  18.3  64.9  050  14  7  10.4   5.7
  9500  17.7  63.9  045  11  6   9.4   5.1 |  19.1  66.4  050  14  7   9.3   5.1
  9250  18.3  64.9  045  11  5   9.1   5.0 |  19.7  67.5  050  13  7   9.0   5.0
  9000  19.0  66.2  045  10  5  10.4   5.7 |  20.4  68.7  050  13  7  10.3   5.7
  8750  19.8  67.6  045  10  5  10.0   5.5 |  21.1  70.0  050  13  6  10.0   5.5
  8500  20.5  68.9  045  10  5  10.2   5.6 |  21.9  71.4  050  12  6   9.5   5.2
  8250  21.2  70.2  045  10  5  10.1   5.5 |  22.5  72.5  055  12  6   9.1   5.0
  8000  22.0  71.6  050  10  5   9.5   5.2 |  23.2  73.8  055  12  6   9.4   5.2
  7750  22.7  72.9  050  10  5   9.6   5.3 |  23.9  75.0  055  12  6   9.6   5.3
  7500  23.4  74.1  050   9  5  10.3   5.6 |  24.7  76.5  055  12  6  10.3   5.6
  7250  24.2  75.6  050   9  5  10.7   5.9 |  25.5  77.9  055  12  6  10.7   5.9
  7000  24.9  76.8  050   9  5   9.8   5.4 |  26.2  79.2  055  11  6  10.4   5.7
  6750  25.7  78.3  050   9  5  10.2   5.6 |  27.0  80.6  055  11  6  10.3   5.7
  6500  26.5  79.7  050   9  4  11.3   6.2 |  27.8  82.0  055  11  6  10.4   5.7
  6250  27.3  81.1  050   8  4  11.8   6.5 |  28.6  83.5  055  11  5  10.7   5.9
  6000  28.2  82.8  050   8  4   9.8   5.4 |  29.3  84.7  055  10  5   9.4   5.2
  5750  28.9  84.0  050   8  4  13.1   7.2 |  30.0  86.0  060  10  5  10.1   5.5
  5500  30.2  86.4  050   7  4  18.6  10.2 |  30.9  87.6  055   9  5  12.4   6.8
  5250  31.4  88.5  050   7  4  14.3   7.8 |  31.7  89.1  055   9  5  10.5   5.8
  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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