Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231247
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0646 MDT Wednesday, July 23, 2014

This forecast is for Wednesday, July 23, 2014:

If the trigger temperature of 91.1 F/32.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1266 ft/min (6.4 m/s)
   Maximum height of thermals.................. 18280 ft MSL (13441 ft AGL)

Forecast maximum temperature................... 99.0 F/37.7 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11666 ft MSL (6827 ft AGL)
Thermal soaring outlook for Thursday 07/24..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:06:56 / 20:34:31 MDT
Total possible sunshine........... 14 hr 27 min 35 sec (867 min 35 sec)
Altitude of sun at 13:20:34 MDT... 70.82 degrees

Upper air data from rawinsonde observation taken on 07/23/2014 at 0600 MDT

Freezing level.................. 17244 ft MSL (12405 ft AGL)
Convective condensation level... 19280 ft MSL (14441 ft AGL)
Lifted condensation level....... 19303 ft MSL (14464 ft AGL)
Lifted index.................... -0.2
K index......................... +17.3

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  -71.7 -97.1   260   40   21   5.5   3.0   72.8 163.1    20.7      M    M
 45000  -62.1 -79.8   260   49   25   8.1   4.4   64.3 147.8    17.0      M    M
 40000  -51.0 -59.8   260   47   24   6.4   3.5   59.0 138.2    14.6      M    M
 38000  -46.4 -51.5   255   43   22   9.2   5.1   57.1 134.8    13.7      M    M
 36000  -42.1 -43.8   250   39   20   1.8   1.0   55.0 131.0    12.5      M    M
 34000  -37.4 -35.3   250   33   17   9.4   5.2   52.2 126.0    10.9      M    M
 32000  -32.8 -27.0   245   26   13   6.2   3.4   50.5 122.9     9.9      M    M
 30000  -28.7 -19.7   270   25   13   8.5   4.7   48.3 118.9     8.4      M    M
 29000  -26.2 -15.2   270   22   12   8.1   4.4   47.7 117.8     8.0      M    M
 28000  -23.9 -11.0   270   20   10   8.4   4.6   46.9 116.5     7.5      M    M
 27000  -21.4  -6.5   260   16    8   6.4   3.5   46.4 115.5     7.2      M    M
 26000  -19.3  -2.7   245   12    6   7.6   4.2   45.5 113.8     6.4      M    M
 25000  -17.2   1.0   225   17    9   4.7   2.6   44.4 111.9     5.6      M    M
 24000  -15.5   4.1   205   20   10   6.5   3.5   42.9 109.2     4.5      M    M
 23000  -13.1   8.4   210   18    9   9.4   5.2   42.2 108.0     3.9      M    M
 22000  -10.7  12.7   215   15    8   8.8   4.8   41.7 107.0     3.5      M    M
 21000   -9.8  14.4   195   12    6  -3.2  -1.7   39.3 102.8     1.4      M    M
 20000   -8.0  17.6   210   12    6   9.7   5.3   38.1 100.6     0.3      M    M
 19500   -6.6  20.1   210   12    6   8.2   4.5   38.1 100.5     0.3      M    M
 19000   -5.3  22.5   200   12    6  10.1   5.6   37.9 100.2     0.1      M    M
 18500   -3.2  26.2   185   12    6   9.2   5.0   37.9 100.1     0.0      M    M
 18000   -1.8  28.8   180   13    7   9.2   5.1   37.8 100.0    -0.0   1221  6.2
 17500   -0.4  31.3   180   12    6   9.2   5.1   37.7  99.8    -0.1   1164  5.9
 17000    1.0  33.8   175   11    6   9.2   5.1   37.6  99.6    -0.2   1108  5.6
 16500    2.4  36.3   175   10    5   9.2   5.1   37.5  99.5    -0.2   1051  5.3
 16000    3.8  38.8   170    9    5   9.1   5.0   37.4  99.4    -0.3    994  5.1
 15500    5.0  41.0   185   12    6   8.0   4.4   37.2  99.0    -0.5    942  4.8
 15000    6.2  43.2   190   14    7   7.7   4.2   37.0  98.5    -0.8    892  4.5
 14500    6.7  44.1   195   13    7   5.5   3.0   36.1  96.9    -1.7    860  4.4
 14000    8.1  46.6   200   13    7   8.7   4.8   36.0  96.7    -1.8    805  4.1
 13500    9.4  48.9   210   12    6   8.9   4.9   35.8  96.5    -2.0    751  3.8
 13000   10.7  51.3   215   12    6   8.9   4.9   35.7  96.3    -2.1    696  3.5
 12500   12.1  53.8   220   13    7   8.2   4.5   35.6  96.0    -2.2    641  3.3
 12000   13.1  55.6   220   14    7   6.9   3.8   35.1  95.3    -2.7    596  3.0
 11500   14.1  57.4   225   17    9   6.9   3.8   34.7  94.4    -3.2    552  2.8
 11000   15.1  59.2   225   19   10   6.8   3.7   34.2  93.6    -3.7    507  2.6
 10500   16.2  61.2   220   15    8   9.1   5.0   33.9  93.0    -4.0    460  2.3
 10250   16.9  62.4   215   15    8   9.7   5.3   33.9  92.9    -4.1    431  2.2
 10000   17.6  63.7   210   15    8   9.6   5.2   33.8  92.9    -4.1    402  2.0
  9750   18.3  64.9   210   15    8   9.6   5.3   33.8  92.9    -4.1    373  1.9
  9500   19.0  66.2   205   15    8   9.6   5.3   33.8  92.9    -4.2    344  1.7
  9250   19.7  67.5   205   15    8   9.5   5.2   33.8  92.9    -4.2    316  1.6
  9000   20.4  68.7   200   15    8   9.8   5.4   33.8  92.9    -4.2    287  1.5
  8750   21.2  70.2   200   15    7   8.8   4.8   33.8  92.8    -4.2    258  1.3
  8500   21.7  71.1   200   14    7   7.6   4.2   33.7  92.6    -4.4    233  1.2
  8250   22.3  72.1   195   14    7   7.8   4.3   33.5  92.3    -4.5    208  1.1
  8000   22.9  73.2   195   13    7   7.8   4.3   33.4  92.1    -4.7    184  0.9
  7750   23.5  74.3   190   13    7   7.8   4.3   33.2  91.8    -4.8    159  0.8
  7500   24.0  75.2   185   14    7   7.8   4.3   33.1  91.5    -5.0    134  0.7
  7250   24.6  76.3   175   14    7   7.8   4.3   32.9  91.3    -5.2    110  0.6
  7000   25.2  77.4   170   15    8   7.8   4.3   32.8  91.0    -5.3     85  0.4
  6750   25.8  78.4   165   17    9   7.8   4.3   32.6  90.7    -5.5     60  0.3
  6500   26.3  79.3   160   20   10   7.7   4.2   32.5  90.4    -5.7     36  0.2
  6250   26.9  80.4   155   24   12   8.0   4.4   32.3  90.2    -5.8     11  0.1
  6000   27.5  81.5   150   27   14   6.9   3.8   32.2  89.9    -6.0      M    M
  5750   28.1  82.6   145   26   13  11.0   6.0   32.0  89.6    -6.2      M    M
  5500   28.6  83.5   145   24   12  -6.5  -3.6   31.8  89.2    -6.4      M    M
  5250   27.2  81.0   135   21   11 -23.7 -13.0   29.6  85.2    -8.5      M    M
  5000   26.2  79.2   130   19   10  -2.0  -1.1   27.7  81.9   -10.3      M    M

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

           07/23/2014 at 0900 MDT          |       07/23/2014 at 1200 MDT
                                           |
K index... +21.4  LI... -0.3               | K index... +24.6  LI... -1.7
CAPE... +13.5  CIN... -62.5                | CAPE... +226.6  CIN... -42.1
                                           |
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 -66.9 -88.4  260  30 15   1.0   0.5 | -67.3 -89.1  265  29 15   1.6   0.9
 45000 -61.4 -78.5  260  46 23   7.7   4.2 | -61.2 -78.2  270  47 24   7.8   4.3
 40000 -50.1 -58.2  265  47 24   6.7   3.7 | -49.9 -57.8  265  47 24   6.7   3.7
 38000 -46.0 -50.8  265  42 21   6.7   3.7 | -45.9 -50.6  265  41 21   6.7   3.7
 36000 -41.4 -42.5  265  35 18   7.5   4.1 | -41.3 -42.3  265  35 18   7.5   4.1
 34000 -37.0 -34.6  265  31 16   7.4   4.1 | -36.8 -34.2  260  30 15   7.4   4.1
 32000 -32.6 -26.7  265  27 14   6.8   3.7 | -32.3 -26.1  255  25 13   7.2   3.9
 30000 -28.7 -19.7  260  18  9   6.5   3.5 | -28.3 -18.9  245  20 10   6.9   3.8
 29000 -26.8 -16.2  250  14  7   6.5   3.6 | -26.2 -15.2  235  17  9   6.9   3.8
 28000 -24.8 -12.6  240  12  6   7.5   4.1 | -24.2 -11.6  230  16  8   6.7   3.7
 27000 -22.5  -8.5  230  12  6   7.5   4.1 | -22.2  -8.0  225  16  8   6.8   3.7
 26000 -20.3  -4.5  220  13  7   7.5   4.1 | -20.2  -4.4  220  16  8   6.8   3.8
 25000 -18.2  -0.8  210  14  7   6.5   3.6 | -18.2  -0.8  215  16  8   6.9   3.8
 24000 -16.3   2.7  210  17  8   6.5   3.6 | -16.0   3.2  215  18  9   7.0   3.8
 23000 -14.4   6.1  205  19 10   6.5   3.6 | -13.9   7.0  215  20 10   7.1   3.9
 22000 -12.4   9.7  200  20 10   6.9   3.8 | -11.7  10.9  215  21 11   6.7   3.7
 21000 -10.4  13.3  200  18  9   7.0   3.8 |  -9.8  14.4  210  20 10   6.9   3.8
 20000  -7.9  17.8  200  15  8   6.8   3.8 |  -7.3  18.9  205  18  9   7.0   3.9
 19500  -6.7  19.9  200  14  7   8.8   4.8 |  -6.2  20.8  205  17  9   8.6   4.7
 19000  -5.5  22.1  205  14  7   8.6   4.7 |  -5.0  23.0  205  17  9   8.5   4.6
 18500  -4.2  24.4  205  13  7   8.9   4.9 |  -3.8  25.2  205  16  8   8.5   4.7
 18000  -2.8  27.0  205  13  7   9.2   5.0 |  -2.5  27.5  205  15  8   8.6   4.7
 17500  -1.5  29.3  210  14  7   9.2   5.0 |  -1.3  29.7  200  14  7   8.6   4.7
 17000  -0.1  31.8  215  14  7   9.2   5.0 |  -0.0  32.0  200  14  7   8.9   4.9
 16500   1.3  34.3  215  14  7   9.2   5.0 |   1.3  34.3  200  13  7   8.9   4.9
 16000   2.6  36.7  215  14  7   9.2   5.1 |   2.6  36.7  200  13  7   8.9   4.9
 15500   4.0  39.2  215  15  8   9.2   5.1 |   3.9  39.0  200  13  7   8.9   4.9
 15000   5.4  41.7  215  15  8   9.2   5.0 |   5.2  41.4  200  13  7   8.8   4.8
 14500   6.7  44.1  215  15  8   9.0   4.9 |   6.5  43.7  200  14  7   8.8   4.8
 14000   8.0  46.4  215  16  8   9.0   5.0 |   7.8  46.0  205  15  8   8.8   4.8
 13500   9.3  48.7  215  17  9   8.9   4.9 |   9.1  48.4  205  15  8   9.2   5.0
 13000  10.7  51.3  215  18  9   8.9   4.9 |  10.4  50.7  205  16  8   9.2   5.0
 12500  12.0  53.6  215  18  9   8.9   4.9 |  11.7  53.1  205  16  8   8.7   4.8
 12000  13.3  55.9  215  18  9   9.0   4.9 |  13.0  55.4  205  16  8   8.8   4.8
 11500  14.5  58.1  215  18  9   8.2   4.5 |  14.3  57.7  205  16  8   8.5   4.7
 11000  15.7  60.3  215  17  9   8.2   4.5 |  15.5  59.9  205  16  8   8.6   4.7
 10500  16.8  62.2  215  17  9   6.1   3.4 |  16.6  61.9  210  16  8   6.9   3.8
 10250  17.3  63.1  215  17  9   7.3   4.0 |  17.2  63.0  210  15  8   8.5   4.6
 10000  17.9  64.2  215  16  8   9.0   4.9 |  17.9  64.2  210  15  8  10.0   5.5
  9750  18.5  65.3  215  16  8   8.0   4.4 |  18.6  65.5  210  14  7   9.1   5.0
  9500  19.1  66.4  215  16  8   6.7   3.7 |  19.2  66.6  210  13  7   7.7   4.2
  9250  19.5  67.1  215  15  8   6.3   3.5 |  19.7  67.5  210  12  6   7.4   4.1
  9000  20.0  68.0  215  15  8   7.1   3.9 |  20.3  68.5  210  11  6   8.0   4.4
  8750  20.6  69.1  215  14  7   6.9   3.8 |  20.9  69.6  205  10  5   8.3   4.5
  8500  21.0  69.8  215  14  7   6.5   3.5 |  21.5  70.7  205   9  5   8.6   4.7
  8250  21.5  70.7  215  14  7   5.9   3.2 |  22.1  71.8  205   8  4   8.3   4.5
  8000  22.0  71.6  210  15  8   7.7   4.2 |  22.8  73.0  205   8  4   9.6   5.2
  7750  22.5  72.5  210  15  8   5.8   3.2 |  23.5  74.3  205   7  4  10.5   5.8
  7500  22.7  72.9  205  15  8   1.9   1.1 |  24.3  75.7  205   7  4   9.8   5.4
  7250  22.8  73.0  200  15  8   1.9   1.0 |  25.0  77.0  205   7  4  10.0   5.5
  7000  23.0  73.4  190  15  8   2.9   1.6 |  25.8  78.4  205   7  4   9.8   5.4
  6750  23.2  73.8  185  16  8   3.6   2.0 |  26.5  79.7  205   7  4  10.1   5.6
  6500  23.4  74.1  180  14  7   3.3   1.8 |  27.3  81.1  205   7  3  10.5   5.8
  6250  23.6  74.5  175  12  6   2.7   1.5 |  28.1  82.6  210   6  3  10.2   5.6
  6000  23.9  75.0  170  10  5   5.5   3.0 |  28.8  83.8  210   6  3  11.1   6.1
  5750  24.6  76.3  165  10  5  13.9   7.6 |  29.9  85.8  210   6  3  18.8  10.3
  5500  25.8  78.4  160   8  4  18.9  10.4 |  31.7  89.1  210   6  3  28.8  15.8
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/23/2014 at 1500 MDT          |       07/23/2014 at 1800 MDT
                                           |
K index... +25.4  LI... -1.3               | K index... +26.5  LI... -0.7
CAPE... +108.1  CIN... -29.9               | CAPE... +80.0  CIN... -35.4
                                           |
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 -68.0 -90.4  260  34 18   2.1   1.2 | -67.8 -90.0  260  36 19   1.7   1.0
 45000 -61.2 -78.2  265  50 26   8.0   4.4 | -61.4 -78.5  265  51 26   7.9   4.3
 40000 -49.7 -57.5  260  49 25   6.7   3.7 | -49.8 -57.6  265  50 26   6.9   3.8
 38000 -45.6 -50.1  260  43 22   6.7   3.7 | -45.6 -50.1  265  44 23   6.9   3.8
 36000 -41.0 -41.8  260  37 19   7.3   4.0 | -41.4 -42.5  265  39 20   7.2   4.0
 34000 -36.6 -33.9  260  31 16   7.3   4.0 | -37.1 -34.8  260  33 17   7.3   4.0
 32000 -32.3 -26.1  255  26 13   7.9   4.3 | -32.2 -26.0  250  26 14   7.9   4.3
 30000 -27.7 -17.9  245  24 12   7.7   4.2 | -27.7 -17.9  245  24 12   7.6   4.2
 29000 -25.4 -13.7  240  23 12   7.7   4.2 | -25.4 -13.7  245  22 12   7.7   4.2
 28000 -23.3  -9.9  235  22 11   7.0   3.9 | -23.2  -9.8  240  21 11   7.2   4.0
 27000 -21.2  -6.2  230  20 10   7.0   3.9 | -21.1  -6.0  230  19 10   7.2   4.0
 26000 -19.1  -2.4  220  18  9   7.1   3.9 | -18.9  -2.0  225  18  9   7.2   4.0
 25000 -17.0   1.4  215  16  8   6.6   3.6 | -16.8   1.8  215  17  9   6.7   3.7
 24000 -15.1   4.8  215  16  8   6.5   3.6 | -14.8   5.4  215  16  8   6.8   3.7
 23000 -13.1   8.4  215  16  8   6.6   3.6 | -12.7   9.1  210  16  8   6.8   3.7
 22000 -11.1  12.0  215  17  9   6.5   3.6 | -10.7  12.7  205  16  8   6.8   3.7
 21000  -9.2  15.4  205  17  9   6.6   3.6 |  -8.7  16.3  205  16  8   6.9   3.8
 20000  -6.8  19.8  190  19 10   6.4   3.5 |  -6.7  19.9  205  17  9   7.0   3.8
 19500  -5.7  21.7  190  20 10   8.2   4.5 |  -5.7  21.7  205  17  9   7.4   4.1
 19000  -4.6  23.7  190  19 10   8.1   4.4 |  -4.7  23.5  205  15  8   7.6   4.2
 18500  -3.4  25.9  190  19 10   8.2   4.5 |  -3.6  25.5  205  14  7   7.6   4.2
 18000  -2.2  28.0  190  18  9   8.4   4.6 |  -2.4  27.7  200  13  7   8.6   4.7
 17500  -1.0  30.2  190  17  9   8.4   4.6 |  -1.2  29.8  200  12  6   8.5   4.7
 17000   0.3  32.5  190  17  9   9.2   5.1 |   0.0  32.0  200  12  6   9.0   4.9
 16500   1.6  34.9  190  16  8   9.2   5.0 |   1.4  34.5  200  11  6   9.3   5.1
 16000   2.9  37.2  190  15  8   9.2   5.1 |   2.8  37.0  200  11  6   9.3   5.1
 15500   4.3  39.7  195  15  8   9.2   5.1 |   4.8  40.6  195  11  6   9.4   5.2
 15000   5.6  42.1  195  14  7   9.3   5.1 |   6.2  43.2  195  11  6   9.4   5.2
 14500   7.0  44.6  195  14  7   9.4   5.2 |   7.6  45.7  195  10  5   9.4   5.1
 14000   8.4  47.1  195  13  7   9.4   5.2 |   9.0  48.2  195  10  5   9.4   5.1
 13500   9.7  49.5  195  12  6   9.2   5.0 |  10.4  50.7  195   9  5   9.1   5.0
 13000  11.1  52.0  195  11  6   9.2   5.1 |  11.8  53.2  190   9  5   9.1   5.0
 12500  12.4  54.3  195  11  5   9.0   4.9 |  13.1  55.6  190   9  4   9.0   5.0
 12000  13.8  56.8  195  10  5   9.0   4.9 |  14.5  58.1  190   8  4   9.1   5.0
 11500  15.1  59.2  195   9  4   8.6   4.7 |  15.8  60.4  190   8  4   8.9   4.9
 11000  16.3  61.3  195   7  4   8.9   4.9 |  17.1  62.8  190   7  4   9.7   5.3
 10500  17.4  63.3  200   6  3   3.9   2.1 |  18.1  64.6  190   6  3   5.4   3.0
 10250  17.7  63.9  200   6  3   7.9   4.3 |  18.7  65.7  190   6  3  10.6   5.8
 10000  18.5  65.3  200   5  3  12.0   6.6 |  19.5  67.1  190   5  3  11.1   6.1
  9750  19.3  66.7  200   5  3  10.3   5.6 |  20.3  68.5  190   5  2   9.8   5.4
  9500  20.0  68.0  205   4  2   6.9   3.8 |  20.9  69.6  190   4  2   6.3   3.5
  9250  20.4  68.7  210   4  2   6.7   3.7 |  21.4  70.5  195   4  2   7.9   4.3
  9000  21.1  70.0  210   4  2  10.1   5.6 |  22.1  71.8  195   4  2  10.6   5.8
  8750  21.9  71.4  215   4  2  10.4   5.7 |  22.8  73.0  195   4  2   9.1   5.0
  8500  22.6  72.7  220   4  2   9.9   5.4 |  23.5  74.3  200   3  2   7.6   4.2
  8250  23.3  73.9  220   4  2   9.6   5.3 |  24.0  75.2  205   3  2   7.7   4.2
  8000  24.0  75.2  225   4  2  10.1   5.5 |  24.6  76.3  210   3  2   8.8   4.8
  7750  24.8  76.6  225   4  2  10.3   5.6 |  25.3  77.5  215   3  1   9.8   5.4
  7500  25.6  78.1  225   4  2  10.0   5.5 |  26.1  79.0  220   3  1  10.0   5.5
  7250  26.3  79.3  230   4  2   9.9   5.4 |  26.8  80.2  220   3  1  10.1   5.5
  7000  27.1  80.8  230   4  2  10.2   5.6 |  27.5  81.5  225   3  2   9.8   5.4
  6750  27.8  82.0  230   4  2  10.7   5.9 |  28.3  82.9  225   3  2  10.4   5.7
  6500  28.6  83.5  235   4  2  10.7   5.9 |  29.1  84.4  225   3  2  11.0   6.0
  6250  29.4  84.9  235   4  2  10.5   5.8 |  29.9  85.8  230   3  2  11.0   6.1
  6000  30.2  86.4  240   4  2  11.3   6.2 |  30.7  87.3  230   3  2  10.4   5.7
  5750  31.3  88.3  240   4  2  19.0  10.4 |  31.5  88.7  230   3  2  10.6   5.8
  5500  33.1  91.6  245   4  2  29.3  16.1 |  32.3  90.1  230   3  2  11.8   6.5
  5250     M     M    M   M  M     M     M |  33.2  91.8  235   3  2  10.8   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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