Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 141508
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0907 MDT Thursday, August 14, 2014

This forecast is for Thursday, August 14, 2014:

If the trigger temperature of 72.1 F/22.3 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 319 ft/min (1.6 m/s)
   Maximum height of thermals.................. 12286 ft MSL (7447 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1015 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................. 10121 ft MSL (5282 ft AGL)
Thermal soaring outlook for Friday 08/15....... Good

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

Remarks...

Sunrise/Sunset.................... 06:26:27 / 20:11:33 MDT
Total possible sunshine........... 13 hr 45 min 6 sec (825 min 6 sec)
Altitude of sun at 13:18:40 MDT... 65.07 degrees

Upper air data from rawinsonde observation taken on 08/14/2014 at 0600 MDT

Freezing level.................. 15538 ft MSL (10699 ft AGL)
Convective condensation level... 7899 ft MSL (3060 ft AGL)
Lifted condensation level....... 10831 ft MSL (5992 ft AGL)
Lifted index.................... -3.2
K index......................... +31.4

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  -67.4 -89.3   230    8    4  -0.9  -0.5   81.7 179.1    31.3      M    M
 45000  -61.3 -78.3   240   40   21   8.3   4.5   67.5 153.4    24.7      M    M
 40000  -53.6 -64.5   230   42   21   7.7   4.2   56.5 133.7    19.1      M    M
 38000  -48.3 -54.9   235   33   17   8.0   4.4   54.6 130.3    18.4      M    M
 36000  -43.3 -45.9   220   32   16   9.9   5.4   53.5 128.3    18.1      M    M
 34000  -38.0 -36.4   220   24   13   8.8   4.8   52.7 126.8    17.9      M    M
 32000  -32.8 -27.0   240   15    8   8.6   4.7   51.9 125.5    17.8      M    M
 30000  -27.4 -17.3   230   17    9   7.7   4.2   51.4 124.5    17.7      M    M
 29000  -25.2 -13.4   230   16    8   7.5   4.1   50.4 122.8    17.2      M    M
 28000  -23.0  -9.4   235   16    8   7.5   4.1   49.6 121.3    16.7      M    M
 27000  -20.8  -5.4   225   16    8   7.5   4.1   48.6 119.5    16.1      M    M
 26000  -18.6  -1.5   220   16    8   7.6   4.2   47.8 118.0    15.6      M    M
 25000  -16.6   2.1   210   16    8   6.4   3.5   46.6 115.9    14.8      M    M
 24000  -14.8   5.4   215   14    7   6.1   3.4   45.3 113.5    13.8      M    M
 23000  -13.0   8.6   220   13    7   6.1   3.4   44.0 111.3    12.9      M    M
 22000  -11.2  11.8   200   12    6   6.2   3.4   42.8 109.0    11.9      M    M
 21000   -9.5  14.9   210   13    7   6.2   3.4   41.5 106.6    10.9      M    M
 20000   -7.2  19.0   205   12    6   6.2   3.4   39.8 103.7     9.6      M    M
 19500   -6.3  20.7   195   14    7   6.2   3.4   39.2 102.6     9.0      M    M
 19000   -5.5  22.1   190   12    6   5.8   3.2   38.5 101.4     8.5      M    M
 18500   -4.7  23.5   205    7    4   5.8   3.2   37.8 100.1     7.9      M    M
 18000   -3.8  25.2   240    4    2   5.8   3.2   37.2  98.9     7.3      M    M
 17500   -3.0  26.6   240    5    3   5.9   3.2   36.5  97.6     6.7      M    M
 17000   -2.1  28.2   240    6    3   5.9   3.2   35.8  96.4     6.1      M    M
 16500   -1.3  29.7   240    7    4   5.9   3.2   35.1  95.2     5.5      M    M
 16000   -0.5  31.1   240    8    4   6.2   3.4   34.5  94.1     4.9      M    M
 15500    0.1  32.2   255    9    4   1.4   0.8   33.5  92.2     4.0      M    M
 15000    0.3  32.5   265   10    5   2.0   1.1   32.1  89.8     2.8      M    M
 14500    0.6  33.1   275   11    6   4.7   2.6   30.8  87.5     1.7      M    M
 14000    1.7  35.1   280   12    6   7.3   4.0   30.5  86.9     1.3      M    M
 13500    2.8  37.0   270   13    7   7.5   4.1   30.1  86.2     0.9      M    M
 13000    3.9  39.0   265   14    7   7.5   4.1   29.8  85.6     0.6      M    M
 12500    5.0  41.0   255   16    8   7.2   3.9   29.4  84.9     0.2      M    M
 12000    5.9  42.6   245   19   10   5.7   3.1   28.8  83.9    -0.4    495  2.5
 11500    6.7  44.1   255   18    9   5.7   3.2   28.2  82.7    -1.0    455  2.3
 11000    7.5  45.5   265   17    9   5.5   3.0   27.5  81.5    -1.6    415  2.1
 10500    8.2  46.8   270   17    9   5.2   2.9   26.8  80.2    -2.4    380  1.9
 10250    8.6  47.5   275   17    9   5.5   3.0   26.4  79.6    -2.8    362  1.8
 10000    8.9  48.0   280   16    8   5.6   3.1   26.1  79.0    -3.2    343  1.7
  9750    9.3  48.7   280   16    8   5.8   3.2   25.8  78.4    -3.5    324  1.6
  9500    9.7  49.5   285   15    8   4.9   2.7   25.5  77.8    -3.9    306  1.6
  9250   10.0  50.0   285   15    7   3.5   1.9   25.0  77.0    -4.3    290  1.5
  9000   10.2  50.4   290   14    7   3.4   1.9   24.5  76.2    -4.9    276  1.4
  8750   10.4  50.7   280   12    6   3.4   1.9   24.0  75.3    -5.4    262  1.3
  8500   10.6  51.1   270   11    6   3.4   1.9   23.5  74.4    -5.9    248  1.3
  8250   10.9  51.6   260   10    5   5.0   2.7   23.1  73.6    -6.4    233  1.2
  8000   11.3  52.3   245   10    5   6.1   3.3   22.8  73.0    -6.7    213  1.1
  7750   11.7  53.1   240    9    5   5.8   3.2   22.5  72.5    -7.1    194  1.0
  7500   12.1  53.8   235    9    4   5.9   3.2   22.2  71.9    -7.4    175  0.9
  7250   12.5  54.5   235    8    4   5.8   3.2   21.9  71.4    -7.7    155  0.8
  7000   12.9  55.2   230    7    4   5.9   3.2   21.6  70.9    -8.1    136  0.7
  6750   13.3  55.9   230    5    3   5.9   3.2   21.3  70.4    -8.4    116  0.6
  6500   13.7  56.7   230    3    2   5.9   3.2   21.0  69.8    -8.8     97  0.5
  6250   14.1  57.4   240    1    0   5.9   3.2   20.7  69.3    -9.1     78  0.4
  6000   14.5  58.1   045    1    1   5.9   3.2   20.4  68.8    -9.5     58  0.3
  5750   14.9  58.8   040    2    1   5.9   3.2   20.1  68.2    -9.8     39  0.2
  5500   15.3  59.5   030    2    1   5.9   3.3   19.8  67.7   -10.2     19  0.1
  5250   15.7  60.3   020    2    1   5.8   3.2   19.5  67.2   -10.5      M    M
  5000   16.1  61.0   010    2    1   6.5   3.6   19.3  66.7   -10.9      M    M

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

           08/14/2014 at 0900 MDT          |       08/14/2014 at 1200 MDT
                                           |
K index... +31.3  LI... -2.6               | K index... +22.8  LI... -2.5
CAPE... +555.4  CIN... -0.9                | CAPE... +519.1  CIN... -1.2
                                           |
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 -66.2 -87.2  235  28 14   1.8   1.0 | -65.9 -86.6  225  25 13   1.3   0.7
 45000 -61.1 -78.0  240  41 21   6.5   3.6 | -61.3 -78.3  235  36 18   6.4   3.5
 40000 -51.2 -60.2  235  39 20   7.2   3.9 | -51.1 -60.0  230  35 18   7.0   3.8
 38000 -46.9 -52.4  235  32 16   7.2   3.9 | -46.8 -52.2  215  27 14   7.0   3.8
 36000 -42.6 -44.7  235  24 12   7.1   3.9 | -42.6 -44.7  195  21 11   8.0   4.4
 34000 -37.2 -35.0  235  20 10   8.1   4.4 | -37.4 -35.3  205  16  8   8.8   4.8
 32000 -32.3 -26.1  240  16  8   8.9   4.9 | -32.1 -25.8  215  11  6   9.5   5.2
 30000 -27.7 -17.9  240  14  7   7.8   4.3 | -27.5 -17.5  235  12  6   7.6   4.2
 29000 -25.3 -13.5  245  13  7   7.9   4.3 | -25.3 -13.5  245  13  7   7.6   4.2
 28000 -23.0  -9.4  245  12  6   7.2   3.9 | -23.0  -9.4  250  14  7   7.3   4.0
 27000 -20.9  -5.6  260  12  6   7.1   3.9 | -20.9  -5.6  255  15  8   7.2   4.0
 26000 -18.9  -2.0  275  12  6   7.1   3.9 | -18.8  -1.8  260  17  9   7.3   4.0
 25000 -16.8   1.8  290  14  7   7.1   3.9 | -16.6   2.1  265  18  9   7.2   3.9
 24000 -14.9   5.2  295  15  8   6.2   3.4 | -14.7   5.5  270  18  9   6.5   3.5
 23000 -13.1   8.4  305  17  9   6.2   3.4 | -12.8   9.0  275  18 10   6.5   3.6
 22000 -11.3  11.7  310  19 10   6.3   3.4 | -10.4  13.3  285  19 10   5.8   3.2
 21000  -9.4  15.1  310  20 10   6.3   3.5 |  -8.7  16.3  290  20 10   5.6   3.1
 20000  -7.6  18.3  310  21 11   6.4   3.5 |  -7.0  19.4  290  20 11   5.6   3.1
 19500  -6.7  19.9  310  21 11   6.4   3.5 |  -6.2  20.8  295  21 11   5.5   3.0
 19000  -5.8  21.6  310  21 11   6.3   3.5 |  -5.5  22.1  295  21 11   4.9   2.7
 18500  -4.9  23.2  310  21 11   6.3   3.5 |  -4.7  23.5  300  22 11   4.9   2.7
 18000  -4.0  24.8  305  21 11   6.1   3.4 |  -4.0  24.8  300  23 12   5.4   2.9
 17500  -3.2  26.2  305  21 11   5.2   2.8 |  -3.2  26.2  300  23 12   5.5   3.0
 17000  -2.4  27.7  305  20 10   5.2   2.9 |  -2.4  27.7  305  23 12   5.6   3.1
 16500  -1.7  28.9  305  20 10   5.4   3.0 |  -1.6  29.1  305  23 12   6.1   3.3
 16000  -0.9  30.4  305  19 10   5.4   3.0 |  -0.7  30.7  310  24 12   6.1   3.3
 15500   0.3  32.5  310  18  9   5.9   3.2 |   0.2  32.4  310  23 12   6.4   3.5
 15000   1.2  34.2  310  17  9   5.9   3.2 |   1.1  34.0  310  23 12   6.4   3.5
 14500   2.0  35.6  310  16  8   6.0   3.3 |   2.0  35.6  315  23 12   6.2   3.4
 14000   2.9  37.2  310  15  8   6.0   3.3 |   2.9  37.2  315  23 12   6.1   3.3
 13500   3.7  38.7  310  15  8   6.2   3.4 |   3.8  38.8  320  22 12   6.2   3.4
 13000   4.6  40.3  305  14  7   6.4   3.5 |   4.6  40.3  320  22 11   6.3   3.4
 12500   5.5  41.9  300  13  7   6.3   3.4 |   5.5  41.9  320  22 11   6.4   3.5
 12000   6.3  43.3  295  13  6   5.9   3.3 |   6.4  43.5  320  22 11   6.5   3.6
 11500   7.2  45.0  285  12  6   5.9   3.2 |   7.4  45.3  320  21 11   6.5   3.6
 11000   8.0  46.4  280  11  6   5.6   3.1 |   8.2  46.8  320  21 11   6.0   3.3
 10500   8.8  47.8  275  10  5   3.6   2.0 |   9.1  48.4  320  20 10   4.1   2.3
 10250   9.0  48.2  270  10  5   4.3   2.4 |   9.3  48.7  315  20 10   3.5   1.9
 10000   9.4  48.9  265  10  5   7.5   4.1 |   9.7  49.5  315  20 10   7.5   4.1
  9750   9.9  49.8  265  10  5   6.9   3.8 |  10.3  50.5  315  19 10   8.7   4.8
  9500  10.4  50.7  260  10  5   6.2   3.4 |  10.9  51.6  315  19 10   7.4   4.1
  9250  10.7  51.3  260  10  5   4.8   2.6 |  11.3  52.3  315  18  9   5.2   2.8
  9000  11.1  52.0  255   9  5   5.4   3.0 |  11.6  52.9  310  17  9   6.0   3.3
  8750  11.5  52.7  255  10  5   5.9   3.2 |  12.1  53.8  310  16  8   7.3   4.0
  8500  11.9  53.4  255  10  5   6.0   3.3 |  12.6  54.7  305  15  8   6.6   3.6
  8250  12.3  54.1  255  10  5   6.4   3.5 |  13.0  55.4  300  14  7   6.0   3.3
  8000  12.7  54.9  255  10  5   6.0   3.3 |  13.4  56.1  295  14  7   6.4   3.5
  7750  13.1  55.6  250  10  5   5.5   3.0 |  13.9  57.0  285  13  7   7.1   3.9
  7500  13.5  56.3  250  10  5   6.0   3.3 |  14.4  57.9  280  12  6   7.8   4.3
  7250  13.9  57.0  245   9  5   6.5   3.5 |  14.9  58.8  280  11  6   8.2   4.5
  7000  14.4  57.9  240   8  4   5.7   3.1 |  15.4  59.7  275  10  5   7.9   4.4
  6750  14.7  58.5  240   7  4   5.3   2.9 |  15.9  60.6  270   9  5   8.6   4.7
  6500  15.2  59.4  235   7  3   6.6   3.6 |  16.6  61.9  270   8  4  10.1   5.6
  6250  15.6  60.1  230   6  3   7.2   3.9 |  17.3  63.1  270   8  4  10.7   5.9
  6000  16.1  61.0  225   6  3   6.6   3.6 |  18.1  64.6  270   8  4  10.2   5.6
  5750  16.6  61.9  220   5  2   8.0   4.4 |  19.0  66.2  270   8  4  14.1   7.8
  5500  17.2  63.0  220   5  2   9.7   5.3 |  20.3  68.5  270   7  4  21.6  11.9
  5250  17.9  64.2  220   4  2   8.4   4.6 |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/14/2014 at 1500 MDT          |       08/14/2014 at 1800 MDT
                                           |
K index... +27.4  LI... -2.3               | K index... +25.2  LI... -2.3
CAPE... +548.9  CIN... -25.9               | CAPE... +499.1  CIN... -32.2
                                           |
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 -65.2 -85.4  220  26 13   1.2   0.7 | -65.0 -85.0  210  26 13   1.3   0.7
 45000 -60.9 -77.6  220  36 19   6.3   3.5 | -60.9 -77.6  215  37 19   6.0   3.3
 40000 -50.9 -59.6  220  39 20   6.6   3.6 | -51.3 -60.3  215  39 20   6.7   3.7
 38000 -46.9 -52.4  215  35 18   6.6   3.6 | -47.3 -53.1  215  36 19   6.7   3.7
 36000 -43.0 -45.4  205  32 16   7.4   4.0 | -43.3 -45.9  215  34 17   7.3   4.0
 34000 -37.7 -35.9  200  30 16   8.8   4.8 | -38.2 -36.8  215  32 17   8.5   4.7
 32000 -32.5 -26.5  190  30 15   8.8   4.8 | -33.1 -27.6  220  31 16   8.5   4.7
 30000 -28.0 -18.4  205  26 13   7.4   4.1 | -28.4 -19.1  225  28 14   7.8   4.3
 29000 -25.2 -13.4  215  25 13   7.4   4.1 | -26.1 -15.0  225  26 13   7.8   4.3
 28000 -23.0  -9.4  225  24 12   7.5   4.1 | -23.2  -9.8  230  24 12   7.9   4.3
 27000 -20.7  -5.3  235  22 11   7.5   4.1 | -20.8  -5.4  240  22 11   7.9   4.3
 26000 -18.4  -1.1  245  21 11   7.6   4.1 | -18.4  -1.1  250  21 11   7.9   4.3
 25000 -16.1   3.0  255  21 11   6.8   3.7 | -16.0   3.2  260  20 11   7.0   3.8
 24000 -14.3   6.3  265  21 11   6.0   3.3 | -14.2   6.4  270  19 10   6.0   3.3
 23000 -12.6   9.3  275  21 11   6.0   3.3 | -12.5   9.5  280  18  9   6.0   3.3
 22000 -10.8  12.6  285  21 11   6.0   3.3 | -10.7  12.7  295  18  9   5.9   3.3
 21000  -9.0  15.8  290  21 11   6.1   3.3 |  -9.0  15.8  295  19 10   5.9   3.2
 20000  -7.2  19.0  295  21 11   6.1   3.3 |  -7.2  19.0  300  19 10   5.9   3.2
 19500  -6.3  20.7  300  21 11   6.2   3.4 |  -6.4  20.5  305  19 10   5.9   3.2
 19000  -5.5  22.1  300  21 11   5.1   2.8 |  -5.5  22.1  305  20 10   6.0   3.3
 18500  -4.7  23.5  305  21 11   5.3   2.9 |  -4.6  23.7  310  20 10   6.1   3.3
 18000  -4.0  24.8  305  22 11   5.2   2.8 |  -3.8  25.2  310  20 10   6.2   3.4
 17500  -3.3  26.1  305  21 11   5.2   2.8 |  -2.9  26.8  310  20 10   6.3   3.5
 17000  -2.6  27.3  305  21 11   5.3   2.9 |  -2.0  28.4  310  20 10   6.4   3.5
 16500  -1.9  28.6  305  20 10   5.7   3.1 |  -1.1  30.0  310  19 10   5.6   3.1
 16000  -1.1  30.0  305  19 10   5.9   3.2 |  -0.3  31.5  310  18  9   5.7   3.1
 15500  -0.4  31.3  305  19 10   6.5   3.6 |   0.5  32.9  310  17  9   6.3   3.5
 15000   0.6  33.1  305  18  9   6.7   3.7 |   1.4  34.5  305  16  8   6.6   3.6
 14500   1.5  34.7  305  18  9   7.0   3.8 |   2.3  36.1  305  14  7   6.9   3.8
 14000   3.1  37.6  305  17  9   7.5   4.1 |   3.3  37.9  305  13  7   7.4   4.0
 13500   4.2  39.6  305  17  9   7.9   4.3 |   4.9  40.8  300  12  6   8.1   4.5
 13000   5.3  41.5  305  16  8   8.0   4.4 |   6.1  43.0  295  11  6   8.4   4.6
 12500   6.5  43.7  305  16  8   8.1   4.4 |   7.3  45.1  295  11  6   8.6   4.7
 12000   7.7  45.9  305  15  8   8.1   4.5 |   8.5  47.3  290  11  5   8.7   4.8
 11500   8.8  47.8  305  14  7   8.0   4.4 |   9.8  49.6  285  10  5   8.6   4.7
 11000  10.0  50.0  305  12  6   7.7   4.2 |  11.0  51.8  280  10  5   8.4   4.6
 10500  11.1  52.0  305  11  5   4.6   2.5 |  12.2  54.0  280   9  5   5.1   2.8
 10250  11.3  52.3  305  10  5   5.3   2.9 |  12.4  54.3  280   9  5   5.7   3.1
 10000  12.0  53.6  305   9  5   9.8   5.4 |  13.1  55.6  275   8  4  10.5   5.8
  9750  12.6  54.7  305   8  4   9.2   5.1 |  13.8  56.8  275   8  4   9.7   5.3
  9500  13.3  55.9  305   7  3   6.9   3.8 |  14.4  57.9  275   8  4   8.4   4.6
  9250  13.7  56.7  305   6  3   5.4   2.9 |  14.9  58.8  270   7  4   6.5   3.6
  9000  14.2  57.6  300   4  2   7.6   4.1 |  15.4  59.7  265   6  3   6.9   3.8
  8750  14.7  58.5  290   3  1   7.6   4.2 |  15.9  60.6  255   5  3   6.9   3.8
  8500  15.2  59.4  265   2  1   6.3   3.5 |  16.4  61.5  245   4  2   6.7   3.7
  8250  15.5  59.9  235   1  0   5.3   2.9 |  16.8  62.2  225   4  2   6.5   3.6
  8000  15.9  60.6  170   1  0   6.7   3.7 |  17.3  63.1  210   4  2   7.1   3.9
  7750  16.3  61.3  145   1  1   8.3   4.5 |  17.8  64.0  200   4  2   7.7   4.2
  7500  16.9  62.4  140   2  1   9.5   5.2 |  18.4  65.1  195   4  2   9.3   5.1
  7250  17.7  63.9  145   2  1  10.2   5.6 |  19.1  66.4  195   4  2  10.3   5.7
  7000  18.4  65.1  145   2  1   9.9   5.5 |  19.8  67.6  195   4  2   9.8   5.4
  6750  19.1  66.4  145   2  1  10.6   5.8 |  20.6  69.1  195   4  2  10.0   5.5
  6500  19.9  67.8  145   2  1  11.2   6.1 |  21.3  70.3  195   4  2  10.3   5.7
  6250  20.8  69.4  145   2  1  11.3   6.2 |  22.1  71.8  195   4  2  10.5   5.8
  6000  21.6  70.9  145   2  1  10.6   5.8 |  22.9  73.2  195   4  2  10.0   5.5
  5750  22.4  72.3  150   2  1  12.6   6.9 |  23.6  74.5  195   4  2  10.0   5.5
  5500  23.5  74.3  145   2  1  15.3   8.4 |  24.3  75.7  195   4  2  10.5   5.8
  5250  24.5  76.1  145   2  1  13.2   7.3 |  25.1  77.2  200   4  2  10.1   5.5
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  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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