Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 261222
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0622 MDT Saturday, July 26, 2014

This forecast is for Saturday, July 26, 2014:

If the trigger temperature of 86.5 F/30.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1169 ft/min (5.9 m/s)
   Maximum height of thermals.................. 17444 ft MSL (12605 ft AGL)

Forecast maximum temperature................... 94.0 F/34.9 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1500 MDT
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................. 10116 ft MSL (5276 ft AGL)
Thermal soaring outlook for Sunday 07/27....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:09:27 / 20:32:05 MDT
Total possible sunshine........... 14 hr 22 min 38 sec (862 min 38 sec)
Altitude of sun at 13:20:36 MDT... 70.18 degrees

Upper air data from rawinsonde observation taken on 07/26/2014 at 0600 MDT

Freezing level.................. 16149 ft MSL (11310 ft AGL)
Convective condensation level... 15530 ft MSL (10691 ft AGL)
Lifted condensation level....... 15947 ft MSL (11108 ft AGL)
Lifted index.................... -2.2
K index......................... +27.9

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  -72.8 -99.0   255   23   12   5.7   3.1   71.7 161.1    21.7      M    M
 45000  -61.7 -79.1   255   37   19   8.7   4.8   65.8 150.4    19.6      M    M
 40000  -51.2 -60.2   255   50   26   8.3   4.6   58.4 137.1    16.0      M    M
 38000  -46.2 -51.2   250   50   26   7.4   4.1   57.1 134.8    15.6      M    M
 36000  -41.2 -42.2   245   47   24   7.7   4.2   56.0 132.8    15.2      M    M
 34000  -36.4 -33.5   245   41   21   6.4   3.5   54.6 130.3    14.5      M    M
 32000  -32.3 -26.1   240   35   18   7.2   4.0   52.3 126.2    13.2      M    M
 30000  -28.0 -18.4   245   31   16   8.5   4.7   49.4 120.9    11.3      M    M
 29000  -25.4 -13.7   240   27   14   8.5   4.7   48.9 120.0    11.0      M    M
 28000  -22.8  -9.0   245   24   13   9.4   5.1   48.5 119.3    10.8      M    M
 27000  -20.7  -5.3   250   22   11   9.5   5.2   47.4 117.2    10.1      M    M
 26000  -18.2  -0.8   255   20   10   5.9   3.3   46.8 116.3     9.8      M    M
 25000  -16.6   2.1   260   18    9   5.9   3.2   45.4 113.7     8.6      M    M
 24000  -15.0   5.0   265   20   10   5.3   2.9   43.7 110.7     7.3      M    M
 23000  -13.1   8.4   270   22   11   8.0   4.4   42.6 108.7     6.3      M    M
 22000  -10.7  12.7   260   24   12   8.1   4.4   42.0 107.6     5.9      M    M
 21000   -8.7  16.3   255   27   14   5.8   3.2   41.0 105.8     5.0      M    M
 20000   -7.1  19.2   250   30   15   5.9   3.2   39.6 103.3     3.8      M    M
 19500   -6.3  20.7   250   27   14   5.7   3.1   38.9 102.0     3.2      M    M
 19000   -5.2  22.6   250   24   12   8.3   4.5   38.4 101.2     2.8      M    M
 18500   -4.2  24.4   250   21   11   5.3   2.9   37.9 100.2     2.4      M    M
 18000   -3.4  25.9   255   19   10   5.5   3.0   37.2  98.9     1.7      M    M
 17500   -3.2  26.2   255   16    8  -1.4  -0.8   35.8  96.5     0.5      M    M
 17000   -2.5  27.5   260   14    7   9.7   5.3   35.0  95.0    -0.3   1140  5.8
 16500   -0.6  30.9   255   15    8   8.8   4.8   34.8  94.7    -0.5   1060  5.4
 16000    0.7  33.3   255   16    8   8.8   4.8   34.7  94.4    -0.7   1007  5.1
 15500    2.0  35.6   260   15    8   8.8   4.8   34.5  94.2    -0.8    953  4.8
 15000    3.2  37.8   260   15    8   8.8   4.8   34.4  93.9    -1.0    900  4.6
 14500    4.5  40.1   245   14    7   8.8   4.9   34.2  93.6    -1.2    847  4.3
 14000    5.8  42.4   235   14    7   8.8   4.9   34.1  93.3    -1.4    794  4.0
 13500    7.1  44.8   240   15    8   8.8   4.9   33.9  93.0    -1.6    740  3.8
 13000    8.4  47.1   245   17    9   8.7   4.8   33.7  92.7    -1.8    687  3.5
 12500    9.7  49.5   250   18   10   8.6   4.7   33.6  92.4    -1.9    633  3.2
 12000   11.0  51.8   255   20   10   8.6   4.7   33.4  92.1    -2.0    579  2.9
 11500   12.3  54.1   250   18    9   8.6   4.7   33.2  91.7    -2.2    525  2.7
 11000   13.6  56.5   245   16    8   8.3   4.5   33.0  91.4    -2.4    471  2.4
 10500   14.8  58.6   235   15    8   7.7   4.2   32.7  90.9    -2.7    422  2.1
 10250   15.3  59.5   235   14    7   7.2   4.0   32.5  90.6    -2.9    399  2.0
 10000   15.8  60.4   240   13    6   7.3   4.0   32.4  90.2    -3.1    375  1.9
  9750   16.4  61.5   245   11    6   7.3   4.0   32.2  89.9    -3.3    352  1.8
  9500   16.9  62.4   250   10    5   7.3   4.0   32.0  89.6    -3.5    329  1.7
  9250   17.4  63.3   255    9    5   7.3   4.0   31.8  89.2    -3.7    305  1.6
  9000   18.0  64.4   260    8    4   7.3   4.0   31.6  88.9    -3.9    282  1.4
  8750   18.5  65.3   255    7    4   7.3   4.0   31.4  88.6    -4.1    258  1.3
  8500   19.0  66.2   245    6    3   7.3   4.0   31.2  88.2    -4.3    235  1.2
  8250   19.6  67.3   235    5    2   7.3   4.0   31.0  87.9    -4.5    212  1.1
  8000   20.1  68.2   220    4    2   7.4   4.1   30.9  87.6    -4.7    188  1.0
  7750   20.6  69.1   190    5    2   7.1   3.9   30.7  87.2    -4.9    165  0.8
  7500   21.1  70.0   170    6    3   4.8   2.6   30.4  86.7    -5.2    145  0.7
  7250   21.3  70.3   160    8    4   2.9   1.6   29.9  85.9    -5.8    131  0.7
  7000   21.3  70.3   155   11    5  -1.9  -1.0   29.3  84.7    -6.5    123  0.6
  6750   21.0  69.8   150   10    5   1.3   0.7   28.3  83.0    -7.5    124  0.6
  6500   21.5  70.7   135    8    4   7.7   4.2   28.1  82.5    -7.8    103  0.5
  6250   22.0  71.6   125    7    4   6.5   3.6   27.8  82.1    -8.0     80  0.4
  6000   22.5  72.5   105    7    4   7.1   3.9   27.6  81.7    -8.2     58  0.3
  5750   23.0  73.4   105    7    4   6.0   3.3   27.4  81.3    -8.5     35  0.2
  5500   23.2  73.8   110    7    4  -3.5  -1.9   26.8  80.3    -9.1     23  0.1
  5250   22.6  72.7   115    7    4  -4.1  -2.2   25.6  78.1   -10.4     32  0.2
  5000   22.6  72.7   120    7    4  -0.0  -0.0   24.9  76.8   -11.1     25  0.1

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

           07/26/2014 at 0900 MDT          |       07/26/2014 at 1200 MDT
                                           |
K index... +31.3  LI... -2.3               | K index... +30.1  LI... -2.8
CAPE... +153.9  CIN... -39.6               | CAPE... +288.0  CIN... -24.6
                                           |
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 -67.7 -89.9  255  20 10   1.5   0.8 | -68.3 -90.9  255  22 11   1.6   0.9
 45000 -61.8 -79.2  250  33 17   7.4   4.1 | -62.2 -80.0  255  31 16   7.7   4.2
 40000 -50.6 -59.1  255  40 21   7.9   4.3 | -50.6 -59.1  255  33 17   8.0   4.4
 38000 -45.9 -50.6  255  39 20   7.9   4.3 | -45.8 -50.4  255  33 17   8.0   4.4
 36000 -41.1 -42.0  255  38 20   7.7   4.2 | -41.0 -41.8  260  33 17   7.8   4.3
 34000 -36.7 -34.1  255  36 18   7.5   4.1 | -36.3 -33.3  255  34 18   7.8   4.3
 32000 -31.6 -24.9  250  33 17   8.1   4.4 | -31.6 -24.9  250  35 18   8.6   4.7
 30000 -27.4 -17.3  250  27 14   7.2   3.9 | -26.4 -15.5  250  31 16   7.8   4.3
 29000 -25.2 -13.4  255  24 12   7.2   4.0 | -24.1 -11.4  255  29 15   7.8   4.3
 28000 -23.1  -9.6  255  22 11   7.0   3.8 | -21.9  -7.4  255  26 13   6.3   3.5
 27000 -21.0  -5.8  260  21 11   7.0   3.9 | -20.0  -4.0  255  22 11   6.3   3.5
 26000 -19.0  -2.2  265  20 10   7.1   3.9 | -18.2  -0.8  255  18  9   6.4   3.5
 25000 -16.9   1.6  270  20 10   6.2   3.4 | -16.3   2.7  255  15  8   6.3   3.5
 24000 -15.2   4.6  270  21 11   5.9   3.2 | -14.4   6.1  265  15  8   6.4   3.5
 23000 -13.5   7.7  270  22 11   5.9   3.2 | -12.6   9.3  275  16  8   6.4   3.5
 22000 -11.8  10.8  270  22 12   6.0   3.3 | -10.8  12.6  275  17  9   5.8   3.2
 21000 -10.0  14.0  265  21 11   6.1   3.3 |  -9.1  15.6  270  18 10   5.8   3.2
 20000  -8.3  17.1  260  19 10   6.1   3.3 |  -7.4  18.7  265  20 10   5.8   3.2
 19500  -7.4  18.7  255  19 10   6.3   3.5 |  -6.5  20.3  265  21 11   6.2   3.4
 19000  -6.4  20.5  255  18  9   7.4   4.0 |  -5.5  22.1  260  21 11   7.0   3.8
 18500  -5.3  22.5  255  17  9   7.3   4.0 |  -4.5  23.9  260  21 11   6.9   3.8
 18000  -3.7  25.3  255  15  8   8.0   4.4 |  -3.5  25.7  260  20 10   7.3   4.0
 17500  -2.5  27.5  250  14  7   7.9   4.4 |  -2.4  27.7  260  19 10   7.3   4.0
 17000  -1.4  29.5  250  13  7   8.0   4.4 |  -1.3  29.7  260  17  9   7.4   4.0
 16500  -0.2  31.6  245  13  6   8.0   4.4 |  -0.3  31.5  255  16  8   7.5   4.1
 16000   0.9  33.6  245  12  6   8.2   4.5 |   0.8  33.4  255  14  7   7.4   4.1
 15500   2.1  35.8  245  11  6   8.4   4.6 |   1.9  35.4  250  13  7   7.9   4.4
 15000   3.3  37.9  240  10  5   8.5   4.6 |   3.0  37.4  245  12  6   7.9   4.3
 14500   4.5  40.1  240  10  5   8.9   4.9 |   4.7  40.5  245  10  5   8.0   4.4
 14000   5.8  42.4  240   9  5   8.9   4.9 |   5.9  42.6  240   9  5   8.0   4.4
 13500   7.1  44.8  245   8  4   8.7   4.8 |   7.1  44.8  240   8  4   8.9   4.9
 13000   8.4  47.1  245   7  4   8.7   4.8 |   8.4  47.1  235   7  4   8.8   4.8
 12500   9.7  49.5  245   7  4   8.9   4.9 |   9.7  49.5  235   7  3   9.2   5.0
 12000  11.0  51.8  245   7  3   9.0   4.9 |  11.1  52.0  235   7  3   9.2   5.1
 11500  12.4  54.3  245   6  3   8.7   4.8 |  12.4  54.3  235   7  3   9.0   4.9
 11000  13.6  56.5  245   6  3   8.2   4.5 |  13.7  56.7  240   6  3   9.4   5.1
 10500  14.8  58.6  240   6  3   3.8   2.1 |  14.8  58.6  240   6  3   4.8   2.6
 10250  14.9  58.8  240   7  3   4.7   2.6 |  15.2  59.4  240   6  3   8.9   4.9
 10000  15.7  60.3  240   7  3  11.0   6.0 |  16.0  60.8  240   6  3  11.5   6.3
  9750  16.4  61.5  245   7  3   9.8   5.4 |  16.8  62.2  245   6  3  10.1   5.6
  9500  17.1  62.8  245   7  3   7.8   4.3 |  17.5  63.5  240   6  3   7.0   3.8
  9250  17.5  63.5  245   6  3   5.7   3.1 |  17.9  64.2  240   5  3   6.9   3.8
  9000  18.0  64.4  245   6  3   7.2   3.9 |  18.5  65.3  240   5  3   8.9   4.9
  8750  18.5  65.3  245   5  3   7.5   4.1 |  19.1  66.4  235   5  2   8.4   4.6
  8500  19.0  66.2  240   5  2   5.7   3.1 |  19.7  67.5  230   4  2   7.8   4.3
  8250  19.4  66.9  235   4  2   4.2   2.3 |  20.3  68.5  230   4  2   7.7   4.2
  8000  19.7  67.5  220   3  2   4.6   2.5 |  20.8  69.4  225   4  2   8.8   4.8
  7750  20.0  68.0  205   3  2   5.0   2.7 |  21.5  70.7  230   4  2   9.7   5.3
  7500  20.4  68.7  195   3  2   6.5   3.5 |  22.2  72.0  230   4  2   9.8   5.4
  7250  20.9  69.6  185   4  2   7.0   3.8 |  23.0  73.4  230   4  2   9.7   5.3
  7000  21.4  70.5  185   5  2   7.7   4.2 |  23.7  74.7  230   4  2  10.2   5.6
  6750  22.0  71.6  180   5  3   7.0   3.8 |  24.5  76.1  225   4  2  11.0   6.0
  6500  22.4  72.3  175   5  3   4.4   2.4 |  25.3  77.5  230   4  2  11.1   6.1
  6250  22.7  72.9  175   5  3   3.3   1.8 |  26.1  79.0  230   4  2  11.2   6.1
  6000  22.9  73.2  170   5  3   5.4   3.0 |  27.0  80.6  230   4  2  10.9   6.0
  5750  23.5  74.3  165   6  3  12.9   7.1 |  27.8  82.0  230   4  2  12.9   7.1
  5500  24.7  76.5  165   5  3  19.7  10.8 |  28.9  84.0  230   4  2  15.1   8.3
  5250     M     M    M   M  M     M     M |  29.9  85.8  235   4  2  13.4   7.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/26/2014 at 1500 MDT          |       07/26/2014 at 1800 MDT
                                           |
K index... +27.0  LI... -1.2               | K index... +26.3  LI... -1.1
CAPE... +149.0  CIN... -39.2               | CAPE... +66.8  CIN... -44.6
                                           |
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 -68.6 -91.5  255  22 12   1.9   1.1 | -67.9 -90.2  260  20 10   1.3   0.7
 45000 -62.0 -79.6  250  32 16   7.7   4.2 | -62.0 -79.6  250  29 15   7.6   4.2
 40000 -50.4 -58.7  250  29 15   7.9   4.3 | -50.5 -58.9  245  27 14   7.9   4.3
 38000 -45.6 -50.1  255  27 14   7.9   4.3 | -45.7 -50.3  250  24 13   7.9   4.3
 36000 -40.9 -41.6  260  25 13   7.9   4.3 | -40.9 -41.6  260  22 11   8.2   4.5
 34000 -36.2 -33.2  255  28 15   7.9   4.4 | -36.0 -32.8  265  25 13   8.3   4.5
 32000 -31.4 -24.5  250  32 16   8.4   4.6 | -31.0 -23.8  265  27 14   8.6   4.7
 30000 -26.6 -15.9  250  29 15   7.2   4.0 | -26.2 -15.2  260  26 14   7.2   3.9
 29000 -24.4 -11.9  250  27 14   7.2   4.0 | -24.1 -11.4  260  26 14   7.2   3.9
 28000 -22.4  -8.3  250  25 13   6.5   3.6 | -22.0  -7.6  255  26 13   6.6   3.6
 27000 -20.4  -4.7  250  23 12   6.5   3.6 | -20.1  -4.2  255  25 13   6.6   3.6
 26000 -18.5  -1.3  250  20 10   6.5   3.6 | -18.1  -0.6  250  24 12   6.6   3.6
 25000 -16.6   2.1  245  17  9   7.0   3.8 | -16.2   2.8  250  23 12   6.4   3.5
 24000 -14.5   5.9  250  16  8   7.0   3.9 | -14.3   6.3  255  21 11   6.4   3.5
 23000 -12.4   9.7  260  15  8   7.1   3.9 | -12.5   9.5  265  19 10   6.4   3.5
 22000 -10.4  13.3  265  15  8   6.8   3.7 | -10.6  12.9  270  18  9   6.6   3.6
 21000  -8.4  16.9  265  17  9   6.8   3.7 |  -8.7  16.3  275  18  9   6.6   3.6
 20000  -6.4  20.5  265  18  9   6.8   3.7 |  -6.7  19.9  280  17  9   6.6   3.6
 19500  -5.4  22.3  260  19 10   6.7   3.7 |  -5.8  21.6  280  17  9   6.7   3.7
 19000  -4.4  24.1  260  19 10   6.6   3.6 |  -4.8  23.4  280  16  8   6.7   3.7
 18500  -3.4  25.9  260  20 10   6.6   3.6 |  -3.8  25.2  285  15  8   6.7   3.7
 18000  -2.5  27.5  260  20 10   6.6   3.6 |  -2.8  27.0  285  15  7   6.8   3.8
 17500  -1.5  29.3  260  19 10   6.6   3.6 |  -1.8  28.8  280  14  7   6.9   3.8
 17000  -0.5  31.1  260  19 10   6.6   3.6 |  -0.8  30.6  280  14  7   7.1   3.9
 16500   0.4  32.7  260  18  9   6.7   3.7 |   0.3  32.5  280  13  7   7.7   4.2
 16000   1.4  34.5  255  17  9   6.7   3.7 |   1.4  34.5  275  13  7   7.6   4.2
 15500   2.4  36.3  255  17  9   7.2   3.9 |   2.6  36.7  270  13  7   8.2   4.5
 15000   3.4  38.1  255  16  8   7.2   3.9 |   3.7  38.7  270  13  7   8.1   4.5
 14500   4.9  40.8  250  15  8   7.4   4.1 |   5.5  41.9  265  12  6   8.4   4.6
 14000   6.0  42.8  250  13  7   7.3   4.0 |   6.7  44.1  270  11  6   8.3   4.6
 13500   7.1  44.8  250  12  6   8.8   4.8 |   8.0  46.4  270  11  5   9.0   4.9
 13000   8.4  47.1  255  10  5   8.6   4.7 |   9.3  48.7  270  10  5   9.0   4.9
 12500   9.7  49.5  255   9  4   9.1   5.0 |  10.6  51.1  275   9  5   8.4   4.6
 12000  11.1  52.0  260   7  4   9.2   5.0 |  11.8  53.2  280   8  4   8.3   4.6
 11500  12.4  54.3  260   6  3   9.0   4.9 |  13.0  55.4  285   8  4   8.4   4.6
 11000  13.7  56.7  265   6  3   9.4   5.1 |  14.3  57.7  290   7  4   8.8   4.8
 10500  14.8  58.6  270   5  3   5.6   3.1 |  15.3  59.5  300   6  3   4.9   2.7
 10250  15.3  59.5  275   5  2   9.5   5.2 |  15.8  60.4  305   5  3   8.7   4.8
 10000  16.2  61.2  280   4  2  11.5   6.3 |  16.5  61.7  310   5  2  10.8   5.9
  9750  17.0  62.6  285   4  2  10.4   5.7 |  17.3  63.1  320   4  2   9.9   5.4
  9500  17.6  63.7  290   4  2   7.1   3.9 |  18.0  64.4  325   4  2   7.4   4.1
  9250  18.1  64.6  290   4  2   7.9   4.3 |  18.5  65.3  340   3  2   7.9   4.3
  9000  18.8  65.8  295   4  2  10.7   5.9 |  19.1  66.4  355   3  2  10.1   5.6
  8750  19.6  67.3  300   3  2   9.9   5.4 |  19.8  67.6  010   3  2   9.5   5.2
  8500  20.3  68.5  305   3  2   9.1   5.0 |  20.5  68.9  025   3  2   8.9   4.9
  8250  20.9  69.6  310   3  2   8.9   4.9 |  21.1  70.0  030   3  2   8.7   4.8
  8000  21.6  70.9  315   3  2   9.2   5.1 |  21.8  71.2  040   3  2   9.4   5.2
  7750  22.2  72.0  320   3  2   9.4   5.2 |  22.5  72.5  040   3  2   9.8   5.4
  7500  22.9  73.2  320   3  1   9.3   5.1 |  23.2  73.8  045   3  2   9.9   5.4
  7250  23.6  74.5  320   3  1   9.3   5.1 |  23.9  75.0  045   3  2   9.8   5.4
  7000  24.2  75.6  320   3  1   9.4   5.1 |  24.7  76.5  050   3  1  10.3   5.6
  6750  25.0  77.0  325   3  1  10.1   5.5 |  25.5  77.9  050   3  2  10.7   5.9
  6500  25.7  78.3  325   3  1  10.5   5.8 |  26.2  79.2  050   3  2  10.5   5.7
  6250  26.5  79.7  325   3  1  10.6   5.8 |  27.0  80.6  055   3  1  10.8   5.9
  6000  27.3  81.1  320   3  1  10.0   5.5 |  27.8  82.0  055   3  1   9.6   5.3
  5750  28.0  82.4  320   3  1   9.5   5.2 |  28.5  83.3  055   3  1  10.3   5.6
  5500  28.7  83.7  320   3  1   9.8   5.4 |  29.4  84.9  055   3  1  12.3   6.8
  5250  29.4  84.9  320   3  1   9.5   5.2 |  30.2  86.4  055   3  1  10.7   5.9
  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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