Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 161219
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0619 MDT Sunday, July 16, 2017

This forecast is for Sunday, July 16, 2017:

If the trigger temperature of 88.1 F/31.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1408 ft/min (7.2 m/s)
   Maximum height of thermals.................. 18749 ft MSL (13910 ft AGL)

Forecast maximum temperature................... 97.0 F/36.6 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13114 ft MSL (8275 ft AGL)
Thermal soaring outlook for Monday 07/17....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:01:36 / 20:39:01 MDT
Total possible sunshine........... 14 hr 37 min 25 sec (877 min 25 sec)
Altitude of sun at 13:20:13 MDT... 72.08 degrees

Upper air data from rawinsonde observation taken on 07/16/2017 at 0600 MDT

Freezing level.................. 16200 ft MSL (11361 ft AGL)
Convective condensation level... 16769 ft MSL (11930 ft AGL)
Lifted condensation level....... 17548 ft MSL (12709 ft AGL)
Lifted index.................... -3.1
K index......................... +25.3

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  -67.9 -90.2   140   12    6   4.6   2.5   79.4 174.9    25.2      M    M
 45000  -57.7 -71.9   090   15    8   6.0   3.3   70.8 159.5    21.8      M    M
 40000  -46.3 -51.3   060    4    2   7.4   4.1   65.9 150.6    19.9      M    M
 38000  -41.8 -43.2   345    6    3   7.4   4.1   63.8 146.8    19.0      M    M
 36000  -37.4 -35.3   340   14    7   6.3   3.5   61.9 143.4    18.2      M    M
 34000  -36.1 -33.0   310   21   11   2.8   1.5   55.5 132.0    14.0      M    M
 32000  -33.0 -27.4   295   16    8   8.6   4.7   50.8 123.5    10.9      M    M
 30000  -28.7 -19.7   270   12    6   6.8   3.7   48.8 119.9     9.6      M    M
 29000  -26.5 -15.7   265    7    4   4.1   2.3   47.8 118.1     8.9      M    M
 28000  -25.3 -13.5   250    3    2   3.7   2.0   45.7 114.2     7.3      M    M
 27000  -23.4 -10.1   145    2    1   7.0   3.9   44.4 111.9     6.4      M    M
 26000  -21.1  -6.0   020    3    2   8.3   4.6   43.6 110.5     5.8      M    M
 25000  -18.6  -1.5   010    8    4   6.5   3.5   43.1 109.6     5.4      M    M
 24000  -17.2   1.0   015   10    5   4.6   2.5   41.3 106.4     4.0      M    M
 23000  -14.9   5.2   360   17    9   9.8   5.4   40.6 105.1     3.4      M    M
 22000  -13.3   8.1   345   14    7   4.5   2.4   39.2 102.5     2.2      M    M
 21000  -10.9  12.4   325   12    6   8.6   4.7   38.5 101.3     1.6      M    M
 20000   -8.4  16.9   310   12    6   8.7   4.8   38.1 100.6     1.2      M    M
 19500   -7.2  19.0   325   11    6   7.3   4.0   37.8 100.1     1.0      M    M
 19000   -6.3  20.7   330   11    6   5.9   3.2   37.2  99.0     0.4      M    M
 18500   -5.4  22.3   330   11    5   7.0   3.8   36.6  97.9    -0.2   1296  6.6
 18000   -4.2  24.4   330   10    5   6.7   3.7   36.3  97.3    -0.5   1246  6.3
 17500   -3.3  26.1   330   10    5   8.6   4.7   35.8  96.4    -1.0   1205  6.1
 17000   -1.6  29.1   335   10    5   7.7   4.2   35.3  95.6    -1.5   1130  5.7
 16500   -0.5  31.1   335    9    5   7.6   4.2   35.0  94.9    -1.8   1081  5.5
 16000    0.8  33.4   335    9    5   8.8   4.8   34.7  94.5    -2.0   1029  5.2
 15500    2.1  35.8   340   10    5   8.7   4.8   34.5  94.2    -2.2    976  5.0
 15000    3.4  38.1   345   10    5   8.7   4.8   34.4  93.9    -2.4    922  4.7
 14500    4.7  40.5   345   11    5   8.7   4.8   34.2  93.6    -2.5    868  4.4
 14000    6.0  42.8   350   11    6   8.7   4.8   34.1  93.4    -2.7    814  4.1
 13500    7.3  45.1   340   10    5   8.7   4.8   33.9  93.0    -2.9    761  3.9
 13000    8.6  47.5   335    9    5   8.7   4.8   33.7  92.7    -3.1    707  3.6
 12500    9.9  49.8   325    9    5   8.6   4.7   33.6  92.4    -3.2    653  3.3
 12000   11.1  52.0   315    9    5   8.4   4.6   33.4  92.0    -3.5    601  3.1
 11500   12.4  54.3   310    7    4   8.4   4.6   33.1  91.6    -3.7    549  2.8
 11000   13.6  56.5   305    5    3   8.4   4.6   32.9  91.2    -4.0    498  2.5
 10500   14.8  58.6   295    3    2   8.6   4.7   32.7  90.8    -4.2    446  2.3
 10250   15.5  59.9   280    2    1   8.8   4.8   32.6  90.7    -4.3    419  2.1
 10000   16.1  61.0   225    1    1   8.7   4.8   32.5  90.6    -4.3    392  2.0
  9750   16.8  62.2   210    2    1   8.7   4.8   32.5  90.4    -4.4    365  1.9
  9500   17.4  63.3   205    4    2   8.7   4.8   32.4  90.3    -4.5    338  1.7
  9250   18.1  64.6   200    5    3   8.8   4.8   32.3  90.1    -4.6    312  1.6
  9000   18.7  65.7   200    7    4   8.6   4.7   32.2  90.0    -4.7    285  1.4
  8750   19.4  66.9   195    7    4   9.2   5.1   32.1  89.9    -4.8    258  1.3
  8500   20.0  68.0   195    7    4   6.8   3.8   32.1  89.7    -4.9    231  1.2
  8250   20.3  68.5   190    7    4   3.2   1.8   31.7  89.0    -5.3    215  1.1
  8000   20.5  68.9   185    7    4   2.7   1.5   31.1  88.0    -5.9    203  1.0
  7750   20.7  69.3   185    8    4   5.6   3.1   30.7  87.2    -6.5    189  1.0
  7500   21.2  70.2   180   10    5   7.9   4.3   30.5  86.8    -6.7    166  0.8
  7250   21.7  71.1   180   11    6   7.3   4.0   30.3  86.5    -6.9    142  0.7
  7000   22.3  72.1   180   13    7   7.4   4.1   30.1  86.2    -7.1    119  0.6
  6750   22.8  73.0   170   15    8   7.4   4.1   29.9  85.9    -7.3     96  0.5
  6500   23.3  73.9   165   18    9   7.4   4.1   29.8  85.6    -7.5     72  0.4
  6250   23.8  74.8   160   21   11   5.8   3.2   29.5  85.2    -7.8     50  0.3
  6000   24.1  75.4   155   24   12  -0.4  -0.2   29.1  84.3    -8.3     36  0.2
  5750   23.8  74.8   150   22   12  -4.5  -2.5   28.1  82.5    -9.3     36  0.2
  5500   23.6  74.5   140   19   10   1.8   1.0   27.2  80.9   -10.2     34  0.2
  5250   24.1  75.4   130   16    8   7.2   3.9   26.8  80.3   -10.5     14  0.1
  5000   24.4  75.9   115   14    7   0.5   0.3   26.5  79.6   -10.9      M    M

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

           07/16/2017 at 0900 MDT          |       07/16/2017 at 1200 MDT
                                           |
K index... +27.6  LI... -1.6               | K index... +27.2  LI... -2.5
CAPE... +158.5  CIN... -108.1              | CAPE... +376.3  CIN... -57.1
                                           |
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 -65.6 -86.1  125  16  8   4.0   2.2 | -65.5 -85.9  135  17  9   3.9   2.1
 45000 -57.6 -71.7  115  12  6   7.5   4.1 | -57.7 -71.9  125  15  8   7.4   4.0
 40000 -46.3 -51.3  115   2  1   5.9   3.2 | -46.6 -51.9  010   1  1   5.7   3.1
 38000 -42.8 -45.0  315   3  2   5.9   3.2 | -43.2 -45.8  320   8  4   5.7   3.1
 36000 -39.2 -38.6  310   9  5   5.6   3.1 | -39.8 -39.6  315  15  8   5.7   3.1
 34000 -36.0 -32.8  320  11  6   5.4   2.9 | -36.4 -33.5  320  15  8   5.8   3.2
 32000 -32.8 -27.0  325  14  7   5.4   3.0 | -32.9 -27.2  320  15  8   5.9   3.3
 30000 -28.9 -20.0  315  11  6   6.6   3.6 | -28.8 -19.8  315  13  7   7.0   3.8
 29000 -26.9 -16.4  310  10  5   6.6   3.6 | -26.7 -16.1  310  12  6   7.0   3.8
 28000 -24.4 -11.9  300   8  4   6.9   3.8 | -24.1 -11.4  305  11  6   6.6   3.6
 27000 -22.4  -8.3  295   8  4   6.9   3.8 | -22.2  -8.0  300  10  5   6.6   3.6
 26000 -20.3  -4.5  290   8  4   7.0   3.8 | -20.2  -4.4  295   8  4   6.6   3.6
 25000 -18.2  -0.8  285   8  4   6.8   3.7 | -18.2  -0.8  290   7  4   6.4   3.5
 24000 -16.3   2.7  300   8  4   6.7   3.7 | -16.3   2.7  305   6  3   6.4   3.5
 23000 -14.3   6.3  320   8  4   6.8   3.7 | -14.4   6.1  320   6  3   6.5   3.6
 22000 -12.3   9.9  335   9  5   6.7   3.7 | -12.5   9.5  335   6  3   7.0   3.9
 21000 -10.4  13.3  340   8  4   6.8   3.7 | -10.4  13.3  335   7  3   7.2   3.9
 20000  -8.4  16.9  345   8  4   6.9   3.8 |  -8.3  17.1  335   7  4   7.3   4.0
 19500  -7.4  18.7  345   8  4   7.1   3.9 |  -7.3  18.9  335   7  4   7.5   4.1
 19000  -6.3  20.7  345   8  4   7.9   4.3 |  -6.1  21.0  335   8  4   7.9   4.3
 18500  -5.2  22.6  340   9  5   7.8   4.3 |  -5.0  23.0  340   8  4   7.9   4.4
 18000  -4.0  24.8  340   9  5   7.9   4.3 |  -3.9  25.0  345   8  4   8.0   4.4
 17500  -2.8  27.0  340  10  5   7.9   4.4 |  -2.7  27.1  345   8  4   8.1   4.4
 17000  -1.7  28.9  340  10  5   8.0   4.4 |  -1.6  29.1  350   8  4   8.1   4.4
 16500  -0.5  31.1  340  11  5   8.3   4.6 |  -0.4  31.3  350   8  4   8.0   4.4
 16000   0.7  33.3  340  11  6   8.3   4.6 |   0.7  33.3  350   8  4   8.0   4.4
 15500   1.9  35.4  340  11  6   8.5   4.7 |   1.9  35.4  345   8  4   8.7   4.8
 15000   3.1  37.6  335  12  6   8.6   4.7 |   3.2  37.8  345   8  4   8.6   4.7
 14500   4.3  39.7  335  12  6   9.1   5.0 |   4.5  40.1  345   8  4   9.0   5.0
 14000   5.7  42.3  330  13  6   9.4   5.1 |   5.9  42.6  340   9  5   9.2   5.0
 13500   7.7  45.9  325  13  7   8.8   4.8 |   7.9  46.2  340  10  5   9.2   5.0
 13000   9.0  48.2  325  13  7   8.8   4.8 |   9.3  48.7  335  10  5   9.2   5.0
 12500  10.3  50.5  320  12  6   8.2   4.5 |  10.6  51.1  330  10  5   9.2   5.1
 12000  11.5  52.7  315  11  6   8.0   4.4 |  11.9  53.4  330  10  5   9.3   5.1
 11500  12.6  54.7  305  10  5   7.6   4.2 |  13.2  55.8  325   9  5   8.9   4.9
 11000  13.7  56.7  300  10  5   7.5   4.1 |  14.4  57.9  315   9  5   9.0   4.9
 10500  14.7  58.5  290  10  5   4.9   2.7 |  15.5  59.9  305   8  4   4.6   2.5
 10250  15.0  59.0  285  10  5   6.8   3.7 |  15.8  60.4  305   8  4   6.8   3.7
 10000  15.7  60.3  285  10  5   9.5   5.2 |  16.5  61.7  300   7  4   9.5   5.2
  9750  16.3  61.3  280  10  5   8.9   4.9 |  17.1  62.8  295   7  4   8.9   4.9
  9500  16.9  62.4  275  10  5   7.1   3.9 |  17.7  63.9  290   7  4   6.4   3.5
  9250  17.3  63.1  275   9  5   6.0   3.3 |  18.1  64.6  285   7  3   5.9   3.3
  9000  17.8  64.0  270   8  4   6.9   3.8 |  18.7  65.7  280   6  3   7.8   4.3
  8750  18.3  64.9  265   7  4   6.7   3.6 |  19.2  66.6  275   6  3   7.4   4.1
  8500  18.8  65.8  260   6  3   5.8   3.2 |  19.8  67.6  270   5  3   7.6   4.1
  8250  19.1  66.4  250   5  3   5.3   2.9 |  20.3  68.5  265   5  3   7.8   4.3
  8000  19.5  67.1  240   4  2   5.3   2.9 |  20.8  69.4  265   5  2   8.7   4.8
  7750  19.9  67.8  225   4  2   5.1   2.8 |  21.5  70.7  260   4  2   9.6   5.2
  7500  20.3  68.5  210   5  3   4.8   2.7 |  22.2  72.0  255   4  2   9.9   5.4
  7250  20.6  69.1  195   6  3   5.0   2.8 |  23.0  73.4  255   4  2  10.5   5.7
  7000  21.0  69.8  190   7  4   4.1   2.3 |  23.7  74.7  255   4  2   9.3   5.1
  6750  21.3  70.3  180   7  4   5.0   2.7 |  24.4  75.9  255   4  2   9.9   5.4
  6500  21.7  71.1  175   7  4   6.9   3.8 |  25.2  77.4  255   4  2  11.6   6.4
  6250  22.2  72.0  175   7  4   6.5   3.5 |  26.1  79.0  255   4  2  11.9   6.5
  6000  22.6  72.7  170   7  3   7.4   4.0 |  26.9  80.4  255   4  2  10.4   5.7
  5750  23.2  73.8  165   6  3  10.2   5.6 |  27.7  81.9  255   4  2  13.2   7.2
  5500  24.1  75.4  165   6  3  11.8   6.5 |  28.9  84.0  255   4  2  17.5   9.6
  5250  24.9  76.8  165   6  3  10.7   5.9 |  30.1  86.2  255   4  2  14.1   7.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/16/2017 at 1500 MDT          |       07/16/2017 at 1800 MDT
                                           |
K index... +19.9  LI... -0.6               | K index... +27.7  LI... -1.4
CAPE... +141.5  CIN... -46.3               | CAPE... +192.0  CIN... -54.6
                                           |
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 -65.3 -85.5  155  17  9   4.2   2.3 | -65.5 -85.9  170  14  7   4.2   2.3
 45000 -57.4 -71.3  155  15  8   7.0   3.8 | -57.8 -72.0  175  11  5   6.7   3.7
 40000 -46.9 -52.4  300   3  2   5.6   3.1 | -47.5 -53.5  300   5  3   5.8   3.2
 38000 -43.5 -46.3  320   9  5   5.6   3.1 | -44.0 -47.2  305   9  5   5.8   3.2
 36000 -40.1 -40.2  320  15  8   6.0   3.3 | -40.6 -41.1  305  14  7   6.7   3.7
 34000 -36.3 -33.3  320  15  8   6.3   3.5 | -36.3 -33.3  300  13  7   7.2   3.9
 32000 -32.5 -26.5  320  14  7   6.5   3.6 | -32.0 -25.6  300  13  7   7.3   4.0
 30000 -28.4 -19.1  310  13  7   7.0   3.8 | -27.9 -18.2  290  12  6   6.7   3.7
 29000 -25.8 -14.4  305  13  7   7.0   3.8 | -25.9 -14.6  280  11  6   6.8   3.7
 28000 -23.7 -10.7  300  13  6   6.8   3.7 | -23.4 -10.1  280  10  5   6.9   3.8
 27000 -21.6  -6.9  310  12  6   6.8   3.8 | -21.3  -6.3  285  10  5   6.9   3.8
 26000 -19.6  -3.3  315  11  6   6.8   3.8 | -19.3  -2.7  295  10  5   6.9   3.8
 25000 -17.5   0.5  320  10  5   7.0   3.9 | -17.2   1.0  305  10  5   6.5   3.6
 24000 -15.4   4.3  330   9  5   7.1   3.9 | -15.4   4.3  315   9  5   6.4   3.5
 23000 -13.3   8.1  335   8  4   7.1   3.9 | -13.5   7.7  325   9  5   6.5   3.6
 22000 -11.2  11.8  350   7  3   7.2   3.9 | -11.6  11.1  335   9  5   7.4   4.1
 21000  -9.1  15.6  350   7  3   7.2   3.9 |  -9.4  15.1  340  10  5   7.7   4.2
 20000  -6.9  19.6  350   7  3   7.2   3.9 |  -7.2  19.0  345  11  5   7.8   4.3
 19500  -5.9  21.4  350   7  3   7.3   4.0 |  -6.1  21.0  350  11  6   7.9   4.3
 19000  -4.8  23.4  350   7  4   7.7   4.2 |  -5.0  23.0  345  11  6   8.0   4.4
 18500  -3.7  25.3  350   7  4   7.7   4.2 |  -3.8  25.2  345  11  6   8.0   4.4
 18000  -2.5  27.5  350   7  4   7.6   4.2 |  -2.7  27.1  345  11  6   8.1   4.5
 17500  -1.4  29.5  350   7  4   7.6   4.2 |  -1.5  29.3  345  11  5   8.2   4.5
 17000  -0.4  31.3  350   7  4   7.8   4.3 |  -0.3  31.5  345  10  5   8.2   4.5
 16500   0.8  33.4  355   7  4   8.6   4.7 |   0.9  33.6  350  10  5   8.2   4.5
 16000   2.1  35.8  355   7  4   8.6   4.7 |   2.0  35.6  350  10  5   8.1   4.5
 15500   3.3  37.9  355   7  3   8.4   4.6 |   3.3  37.9  350   9  5   8.5   4.6
 15000   4.5  40.1  355   6  3   8.5   4.6 |   4.5  40.1  350   9  5   8.5   4.7
 14500   5.7  42.3  355   5  3   8.6   4.7 |   5.8  42.4  350   8  4   8.9   4.9
 14000   7.6  45.7  350   5  2   8.7   4.8 |   7.2  45.0  350   8  4   9.2   5.1
 13500   8.9  48.0  350   4  2   8.8   4.8 |   9.2  48.6  350   7  4   8.5   4.7
 13000  10.1  50.2  350   4  2   8.8   4.8 |  10.5  50.9  350   7  4   8.4   4.6
 12500  11.4  52.5  345   4  2   8.9   4.9 |  11.8  53.2  355   7  3   8.8   4.8
 12000  12.7  54.9  340   4  2   9.0   4.9 |  13.1  55.6  355   6  3   9.0   4.9
 11500  14.0  57.2  335   3  2   8.9   4.9 |  14.4  57.9  355   5  3   8.4   4.6
 11000  15.3  59.5  325   3  2   8.6   4.7 |  15.6  60.1  360   4  2   8.1   4.4
 10500  16.7  62.1  315   3  2   5.6   3.0 |  16.7  62.1  005   4  2  11.2   6.1
 10250  17.0  62.6  310   4  2   6.2   3.4 |  17.7  63.9  005   3  2  11.3   6.2
 10000  17.7  63.9  305   4  2  10.7   5.9 |  18.3  64.9  010   3  1   7.1   3.9
  9750  18.5  65.3  300   4  2  10.1   5.5 |  18.9  66.0  015   3  1   8.3   4.6
  9500  19.2  66.6  295   4  2   8.0   4.4 |  19.5  67.1  020   2  1   7.8   4.3
  9250  19.6  67.3  295   4  2   7.9   4.3 |  20.0  68.0  025   2  1   8.8   4.8
  9000  20.3  68.5  295   4  2  10.4   5.7 |  20.7  69.3  030   2  1   9.7   5.3
  8750  21.0  69.8  290   4  2   9.6   5.3 |  21.4  70.5  040   2  1   9.4   5.1
  8500  21.7  71.1  290   4  2  10.7   5.9 |  22.1  71.8  045   2  1   9.8   5.4
  8250  22.5  72.5  290   4  2  11.1   6.1 |  22.8  73.0  050   2  1   9.9   5.4
  8000  23.3  73.9  290   4  2   9.7   5.3 |  23.5  74.3  050   2  1   9.1   5.0
  7750  24.0  75.2  285   4  2   9.3   5.1 |  24.2  75.6  055   2  1   8.9   4.9
  7500  24.7  76.5  285   4  2  10.1   5.5 |  24.8  76.6  055   2  1   9.8   5.4
  7250  25.5  77.9  285   4  2  10.8   5.9 |  25.6  78.1  055   2  1  10.5   5.8
  7000  26.3  79.3  280   4  2   9.7   5.3 |  26.4  79.5  055   2  1   9.9   5.5
  6750  27.0  80.6  280   4  2   9.7   5.3 |  27.1  80.8  055   2  1   9.9   5.4
  6500  27.8  82.0  280   4  2  11.4   6.2 |  27.9  82.2  060   2  1  10.6   5.8
  6250  28.6  83.5  275   4  2  12.4   6.8 |  28.7  83.7  060   2  1  11.1   6.1
  6000  29.5  85.1  275   4  2  10.2   5.6 |  29.5  85.1  060   2  1  10.2   5.6
  5750  30.2  86.4  275   4  2  12.8   7.0 |  30.2  86.4  065   2  1  10.4   5.7
  5500  31.5  88.7  275   4  2  18.1   9.9 |  31.1  88.0  060   2  1  11.9   6.6
  5250  32.7  90.9  280   4  2  14.8   8.1 |  31.9  89.4  055   2  1  11.5   6.3
  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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