Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 121257
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0657 MDT Sunday, April 12, 2015

This forecast is for Sunday, April 12, 2015:

If the trigger temperature of 63.7 F/17.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1188 ft/min (6.0 m/s)
   Maximum height of thermals.................. 18239 ft MSL (13400 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... 1300 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................. 9511 ft MSL (4672 ft AGL)
Thermal soaring outlook for Monday 04/13....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:42:08 / 19:47:27 MDT
Total possible sunshine........... 13 hr 5 min 19 sec (785 min 19 sec)
Altitude of sun at 13:14:57 MDT... 59.66 degrees

Upper air data from rawinsonde observation taken on 04/12/2015 at 0600 MDT

Freezing level.................. 11124 ft MSL (6285 ft AGL)
Convective condensation level... 19286 ft MSL (14447 ft AGL)
Lifted condensation level....... 18547 ft MSL (13708 ft AGL)
Lifted index.................... +4.4
K index......................... +3.4

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  -60.3 -76.5   250   19   10  -7.8  -4.3  101.5 214.7    45.7      M    M
 45000  -57.6 -71.7   285   19   10  -0.5  -0.3   79.9 175.8    35.9      M    M
 40000  -60.6 -77.1   265   30   15  -3.4  -1.9   52.2 126.0    20.3      M    M
 38000  -59.3 -74.7   245   40   21  -2.9  -1.6   45.3 113.6    16.3      M    M
 36000  -55.7 -68.3   240   41   21   8.4   4.6   41.9 107.4    14.3      M    M
 34000  -50.8 -59.4   235   41   21   6.3   3.5   40.8 105.4    13.9      M    M
 32000  -47.3 -53.1   235   41   21   3.4   1.8   36.5  97.7    11.2      M    M
 30000  -43.8 -46.8   250   40   21   7.0   3.9   33.3  91.9     9.1      M    M
 29000  -41.5 -42.7   250   40   21   8.2   4.5   32.4  90.4     8.6      M    M
 28000  -39.0 -38.2   250   40   21   8.8   4.8   31.9  89.5     8.3      M    M
 27000  -36.4 -33.5   245   41   21   8.9   4.9   31.6  88.8     8.1      M    M
 26000  -33.9 -29.0   245   41   21   8.7   4.8   31.0  87.9     7.8      M    M
 25000  -31.3 -24.3   245   41   21   9.0   5.0   30.7  87.2     7.6      M    M
 24000  -29.2 -20.6   240   42   22   6.8   3.7   29.7  85.4     6.8      M    M
 23000  -26.5 -15.7   245   43   22   8.9   4.9   29.4  84.9     6.7      M    M
 22000  -24.5 -12.1   250   44   23   6.3   3.4   28.3  82.9     5.8      M    M
 21000  -22.3  -8.1   245   39   20   7.6   4.2   27.4  81.2     5.1      M    M
 20000  -21.0  -5.8   240   34   18   0.2   0.1   25.5  77.8     3.5      M    M
 19500  -20.7  -5.3   240   34   17   4.7   2.6   24.1  75.3     2.4      M    M
 19000  -19.7  -3.5   245   33   17   3.3   1.8   23.5  74.3     2.0      M    M
 18500  -19.2  -2.6   245   33   17   3.8   2.1   22.3  72.2     1.0      M    M
 18000  -19.1  -2.4   240   33   17   3.9   2.2   20.9  69.5    -0.4   1284  6.5
 17500  -17.5   0.5   240   32   17   8.2   4.5   20.3  68.5    -1.0   1214  6.2
 17000  -16.1   3.0   235   32   16   9.4   5.2   20.2  68.3    -1.1   1158  5.9
 16500  -14.7   5.5   240   30   16   9.4   5.2   20.1  68.2    -1.1   1101  5.6
 16000  -13.3   8.1   240   29   15   9.4   5.2   20.1  68.1    -1.1   1044  5.3
 15500  -11.9  10.6   245   27   14   9.4   5.2   20.0  68.0    -1.2    987  5.0
 15000  -10.5  13.1   245   26   13   9.3   5.1   19.9  67.9    -1.3    930  4.7
 14500   -9.1  15.6   250   24   12   9.1   5.0   19.8  67.7    -1.4    874  4.4
 14000   -7.8  18.0   255   23   12   9.1   5.0   19.8  67.6    -1.4    819  4.2
 13500   -6.4  20.5   260   23   12   9.1   5.0   19.6  67.3    -1.6    763  3.9
 13000   -5.0  23.0   265   23   12   9.1   5.0   19.5  67.1    -1.7    708  3.6
 12500   -3.7  25.3   265   24   12   9.1   5.0   19.4  67.0    -1.8    652  3.3
 12000   -2.3  27.9   270   24   12   9.1   5.0   19.3  66.8    -1.9    597  3.0
 11500   -1.0  30.2   275   22   11   9.1   5.0   19.2  66.6    -2.0    542  2.8
 11000    0.4  32.7   280   20   10   9.1   5.0   19.1  66.4    -2.1    486  2.5
 10500    1.7  35.1   270   22   11   9.7   5.3   18.9  66.1    -2.3    431  2.2
 10250    2.4  36.3   270   23   12   6.6   3.6   18.9  66.0    -2.3    403  2.0
 10000    2.8  37.0   265   24   12   5.9   3.2   18.5  65.3    -2.7    385  2.0
  9750    3.4  38.1   260   24   12   8.5   4.6   18.3  65.0    -2.9    360  1.8
  9500    4.0  39.2   260   24   12   7.9   4.4   18.2  64.8    -3.0    334  1.7
  9250    4.6  40.3   255   24   12   8.1   4.4   18.1  64.6    -3.1    309  1.6
  9000    5.2  41.4   250   24   12   8.0   4.4   18.0  64.4    -3.3    284  1.4
  8750    5.8  42.4   250   23   12   8.0   4.4   17.8  64.1    -3.4    258  1.3
  8500    6.4  43.5   250   22   11   8.0   4.4   17.7  63.9    -3.5    233  1.2
  8250    7.0  44.6   255   21   11   8.0   4.4   17.6  63.6    -3.7    208  1.1
  8000    7.6  45.7   255   20   10   8.0   4.4   17.4  63.4    -3.8    182  0.9
  7750    8.1  46.6   255   18    9   8.0   4.4   17.3  63.2    -4.0    157  0.8
  7500    8.7  47.7   255   16    8   8.1   4.4   17.2  62.9    -4.1    132  0.7
  7250    9.3  48.7   250   14    7   8.0   4.4   17.0  62.7    -4.3    106  0.5
  7000    9.9  49.8   250   11    6   8.1   4.4   16.9  62.4    -4.4     81  0.4
  6750   10.5  50.9   245   10    5   8.0   4.4   16.8  62.2    -4.6     56  0.3
  6500   11.1  52.0   235    8    4   8.3   4.6   16.6  61.9    -4.7     30  0.2
  6250   11.7  53.1   225    6    3   7.0   3.8   16.5  61.7    -4.9      5  0.0
  6000   12.3  54.1   205    5    3  10.6   5.8   16.3  61.4    -5.1      M    M
  5750   12.7  54.9   200    4    2  -9.0  -4.9   16.0  60.8    -5.4      M    M
  5500   11.3  52.3   200    3    2 -12.8  -7.0   13.9  57.0    -7.5      M    M
  5250   11.5  52.7   200    2    1  10.6   5.8   13.3  55.9    -8.1      M    M
  5000   11.7  53.1   200    1    1 -16.0  -8.8   12.7  54.9    -8.7      M    M

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

           04/12/2015 at 0900 MDT          |       04/12/2015 at 1200 MDT
                                           |
K index... +17.7  LI... +0.7               | K index... -0.8  LI... +2.1
CAPE... 0.0  CIN... -2.1                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -59.1 -74.4  270  14  7   1.0   0.5 | -58.8 -73.8  260  15  8   0.4   0.2
 45000 -57.5 -71.5  270  11  6   1.1   0.6 | -58.2 -72.8  255  21 11   0.9   0.5
 40000 -55.8 -68.4  270  35 18   1.2   0.7 | -56.4 -69.5  260  33 17   1.2   0.7
 38000 -54.5 -66.1  265  42 22   3.0   1.6 | -54.8 -66.6  260  37 19   4.0   2.2
 36000 -52.7 -62.9  255  47 24   3.0   1.6 | -52.4 -62.3  250  42 21   4.0   2.2
 34000 -50.7 -59.3  245  52 27   6.4   3.5 | -50.0 -58.0  245  46 24   4.6   2.5
 32000 -47.0 -52.6  245  52 27   6.2   3.4 | -47.2 -53.0  250  44 23   4.6   2.5
 30000 -42.7 -44.9  245  52 27   6.6   3.6 | -43.9 -47.0  255  41 21   6.1   3.3
 29000 -40.8 -41.4  245  51 26   6.6   3.6 | -42.1 -43.8  265  38 20   6.1   3.3
 28000 -38.8 -37.8  245  50 26   6.6   3.6 | -40.3 -40.5  275  36 19   6.1   3.3
 27000 -36.8 -34.2  245  49 25   6.4   3.5 | -38.4 -37.1  285  35 18   6.4   3.5
 26000 -35.0 -31.0  250  46 24   6.1   3.3 | -36.4 -33.5  290  34 17   6.9   3.8
 25000 -33.1 -27.6  255  43 22   6.1   3.3 | -34.3 -29.7  295  33 17   6.9   3.8
 24000 -31.3 -24.3  260  41 21   6.1   3.3 | -32.2 -26.0  300  32 16   7.0   3.8
 23000 -29.5 -21.1  260  39 20   6.2   3.4 | -30.1 -22.2  305  32 16   7.3   4.0
 22000 -27.6 -17.7  265  37 19   6.2   3.4 | -27.9 -18.2  310  31 16   7.2   4.0
 21000 -25.8 -14.4  270  35 18   6.5   3.5 | -25.7 -14.3  310  31 16   8.2   4.5
 20000 -23.8 -10.8  270  34 17   6.7   3.7 | -23.1  -9.6  315  32 16   8.6   4.7
 19500 -22.8  -9.0  270  33 17   6.8   3.7 | -21.8  -7.2  315  32 17   8.6   4.7
 19000 -21.8  -7.2  270  33 17   6.9   3.8 | -20.5  -4.9  315  33 17   8.6   4.7
 18500 -20.8  -5.4  270  32 16   7.4   4.0 | -19.2  -2.6  315  33 17   8.6   4.7
 18000 -19.7  -3.5  275  31 16   8.1   4.4 | -17.9  -0.2  315  32 16   8.6   4.7
 17500 -18.5  -1.3  275  31 16   8.1   4.4 | -16.6   2.1  315  31 16   8.6   4.7
 17000 -17.2   1.0  275  30 15   8.4   4.6 | -15.5   4.1  315  29 15   7.0   3.8
 16500 -16.0   3.2  275  29 15   8.4   4.6 | -14.4   6.1  320  28 14   7.2   3.9
 16000 -14.8   5.4  275  29 15   8.2   4.5 | -13.4   7.9  315  26 13   6.5   3.6
 15500 -13.6   7.5  270  28 14   8.2   4.5 | -12.4   9.7  315  24 12   6.4   3.5
 15000 -12.4   9.7  270  27 14   8.5   4.6 | -11.0  12.2  305  22 11   6.3   3.5
 14500 -10.4  13.3  270  25 13   8.9   4.9 | -10.1  13.8  295  21 11   6.4   3.5
 14000  -9.1  15.6  270  24 12   8.5   4.7 |  -9.1  15.6  290  21 11   7.3   4.0
 13500  -7.8  18.0  275  22 11   8.5   4.7 |  -8.0  17.6  290  21 11   7.4   4.1
 13000  -6.6  20.1  275  19 10   6.7   3.7 |  -6.9  19.6  285  21 11   7.6   4.2
 12500  -5.7  21.7  280  16  8   5.9   3.2 |  -5.8  21.6  290  20 10   7.7   4.2
 12000  -4.9  23.2  295  13  6   5.6   3.1 |  -4.6  23.7  290  19 10   7.6   4.2
 11500  -4.1  24.6  305  12  6   5.5   3.0 |  -3.5  25.7  290  17  9   7.6   4.2
 11000  -3.3  26.1  320  13  7   6.6   3.6 |  -2.5  27.5  295  15  8   6.5   3.5
 10500  -2.2  28.0  330  16  8   6.6   3.6 |  -1.6  29.1  300  12  6   6.7   3.7
 10250  -1.7  28.9  330  18  9   9.9   5.4 |  -1.2  29.8  300  11  6   3.5   1.9
 10000  -0.8  30.6  335  19 10  10.1   5.5 |  -1.0  30.2  305   9  5   3.9   2.2
  9750  -0.2  31.6  335  19 10   6.9   3.8 |  -0.5  31.1  310   8  4   7.4   4.0
  9500   0.4  32.7  335  20 10   7.8   4.3 |  -0.1  31.8  315   7  3   6.6   3.6
  9250   1.0  33.8  340  21 11   7.4   4.1 |   0.4  32.7  325   6  3   6.4   3.5
  9000   1.5  34.7  340  20 10   7.8   4.3 |   0.8  33.4  325   5  3   7.5   4.1
  8750   2.1  35.8  340  19 10   8.2   4.5 |   1.5  34.7  330   5  2   9.0   4.9
  8500   2.7  36.9  340  19 10   8.3   4.5 |   2.1  35.8  330   4  2   8.5   4.7
  8250   3.3  37.9  340  18  9   7.7   4.2 |   2.7  36.9  335   4  2   9.5   5.2
  8000   3.7  38.7  335  17  9   5.9   3.3 |   3.4  38.1  330   4  2  10.2   5.6
  7750   4.1  39.4  335  15  8   4.6   2.5 |   4.2  39.6  330   3  2  10.0   5.5
  7500   4.4  39.9  330  14  7   4.0   2.2 |   4.9  40.8  325   3  2  10.1   5.5
  7250   4.6  40.3  325  12  6   2.9   1.6 |   5.7  42.3  320   3  2  10.1   5.6
  7000   4.8  40.6  325  10  5   2.6   1.4 |   6.4  43.5  320   3  2  10.2   5.6
  6750   5.1  41.2  320   8  4   3.0   1.6 |   7.2  45.0  315   3  2  10.1   5.6
  6500   5.4  41.7  310   6  3   4.4   2.4 |   8.0  46.4  315   3  2  10.7   5.9
  6250   5.8  42.4  305   5  3   5.8   3.2 |   8.8  47.8  310   3  1  11.6   6.4
  6000   6.3  43.3  295   4  2   5.5   3.0 |   9.7  49.5  310   3  1  10.3   5.6
  5750   6.8  44.2  280   3  1   7.4   4.1 |  10.4  50.7  305   3  1  11.5   6.3
  5500   7.5  45.5  280   2  1   9.7   5.3 |  11.4  52.5  305   3  1  15.5   8.5
  5250   8.2  46.8  285   3  1   9.7   5.3 |  12.6  54.7  310   3  2  15.6   8.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/12/2015 at 1500 MDT          |       04/12/2015 at 1800 MDT
                                           |
K index... -13.0  LI... +3.1               | K index... -2.3  LI... +3.5
CAPE... 0.0  CIN... -1.3                   | CAPE... 0.0  CIN... M
                                           |
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 -59.0 -74.2  265  19 10   0.9   0.5 | -59.4 -74.9  275  19 10   0.6   0.4
 45000 -57.6 -71.7  270  27 14   0.9   0.5 | -58.4 -73.1  280  26 13   1.0   0.5
 40000 -56.1 -69.0  270  35 18   1.0   0.5 | -56.7 -70.1  285  33 17   1.1   0.6
 38000 -55.2 -67.4  270  36 19   2.2   1.2 | -55.8 -68.4  290  33 17   1.9   1.0
 36000 -53.8 -64.8  275  36 18   2.3   1.2 | -54.7 -66.5  300  33 17   1.9   1.0
 34000 -52.3 -62.1  280  35 18   5.4   2.9 | -53.1 -63.6  310  33 17   7.0   3.9
 32000 -48.8 -55.8  310  35 18   5.1   2.8 | -48.7 -55.7  320  38 20   6.5   3.6
 30000 -45.3 -49.5  325  39 20   7.8   4.3 | -44.5 -48.1  320  42 22   7.8   4.3
 29000 -42.9 -45.2  325  38 20   7.9   4.3 | -42.2 -44.0  325  42 21   7.8   4.3
 28000 -40.5 -40.9  325  37 19   7.9   4.3 | -39.9 -39.8  325  42 21   7.8   4.3
 27000 -38.2 -36.8  325  36 19   8.0   4.4 | -37.5 -35.5  325  41 21   7.9   4.3
 26000 -35.7 -32.3  325  35 18   8.0   4.4 | -35.2 -31.4  325  38 19   7.9   4.3
 25000 -33.3 -27.9  320  34 18   8.0   4.4 | -32.8 -27.0  325  34 18   7.9   4.3
 24000 -30.9 -23.6  320  33 17   7.7   4.2 | -30.4 -22.7  325  31 16   7.9   4.3
 23000 -28.8 -19.8  320  32 16   7.2   3.9 | -28.0 -18.4  320  30 16   7.9   4.3
 22000 -26.6 -15.9  315  31 16   7.2   3.9 | -25.7 -14.3  320  30 15   7.9   4.3
 21000 -24.4 -11.9  310  30 15   8.2   4.5 | -23.3  -9.9  320  29 15   7.5   4.1
 20000 -21.9  -7.4  305  29 15   8.3   4.6 | -21.1  -6.0  320  26 14   7.5   4.1
 19500 -20.7  -5.3  300  29 15   8.3   4.6 | -19.9  -3.8  320  25 13   7.5   4.1
 19000 -19.4  -2.9  300  29 15   8.4   4.6 | -18.8  -1.8  320  24 12   7.6   4.1
 18500 -18.2  -0.8  295  30 15   7.7   4.2 | -17.7   0.1  315  23 12   7.2   3.9
 18000 -17.1   1.2  295  29 15   7.3   4.0 | -16.6   2.1  315  23 12   7.1   3.9
 17500 -16.0   3.2  295  28 14   7.3   4.0 | -15.6   3.9  315  24 12   7.4   4.1
 17000 -14.9   5.2  295  27 14   7.4   4.1 | -14.3   6.3  315  24 12   8.8   4.8
 16500 -13.8   7.2  290  27 14   7.4   4.1 | -13.0   8.6  310  24 12   8.9   4.9
 16000 -12.7   9.1  290  27 14   7.1   3.9 | -11.8  10.8  310  24 12   6.9   3.8
 15500 -11.1  12.0  290  27 14   7.1   3.9 | -10.3  13.5  320  22 11   6.9   3.8
 15000 -10.0  14.0  295  25 13   7.4   4.1 |  -9.3  15.3  320  20 10   6.2   3.4
 14500  -8.9  16.0  300  23 12   7.4   4.0 |  -8.3  17.1  330  18  9   6.2   3.4
 14000  -7.7  18.1  305  21 11   7.7   4.2 |  -7.3  18.9  335  17  8   7.4   4.1
 13500  -6.6  20.1  310  18  9   7.8   4.3 |  -6.3  20.7  340  15  8   7.4   4.0
 13000  -5.4  22.3  315  16  8   7.3   4.0 |  -5.1  22.8  340  13  7   8.1   4.4
 12500  -4.4  24.1  315  14  7   7.2   4.0 |  -4.0  24.8  345  12  6   8.2   4.5
 12000  -3.3  26.1  320  12  6   6.7   3.7 |  -2.7  27.1  345  11  6   8.5   4.6
 11500  -2.4  27.7  320  10  5   6.6   3.6 |  -1.5  29.3  345  10  5   8.6   4.7
 11000  -1.4  29.5  320   8  4   6.9   3.8 |  -0.3  31.5  345   9  5   7.2   4.0
 10500  -0.4  31.3  315   7  4   7.6   4.1 |   0.7  33.3  345   8  4   6.3   3.5
 10250   0.1  32.2  310   7  4   4.9   2.7 |   1.2  34.2  345   8  4   9.9   5.4
 10000   0.4  32.7  310   7  3   5.7   3.1 |   2.1  35.8  340   7  4  10.6   5.8
  9750   1.0  33.8  305   6  3   8.9   4.9 |   2.7  36.9  340   7  4   7.5   4.1
  9500   1.6  34.9  300   6  3   8.3   4.6 |   3.3  37.9  335   6  3   8.5   4.7
  9250   2.2  36.0  300   6  3   7.7   4.2 |   3.9  39.0  330   6  3   7.6   4.2
  9000   2.7  36.9  295   6  3   8.0   4.4 |   4.5  40.1  325   6  3   7.6   4.2
  8750   3.4  38.1  295   6  3   9.2   5.1 |   5.1  41.2  315   5  3   8.2   4.5
  8500   4.0  39.2  295   6  3   9.0   4.9 |   5.7  42.3  305   5  3   8.1   4.4
  8250   4.6  40.3  290   6  3  10.3   5.6 |   6.3  43.3  300   5  3   7.4   4.1
  8000   5.4  41.7  290   6  3  10.5   5.8 |   6.8  44.2  290   5  3   7.3   4.0
  7750   6.2  43.2  290   6  3   9.5   5.2 |   7.4  45.3  285   5  3   7.7   4.2
  7500   6.9  44.4  285   6  3   9.8   5.4 |   8.0  46.4  280   5  3   8.4   4.6
  7250   7.6  45.7  285   6  3  10.4   5.7 |   8.7  47.7  280   5  3  10.0   5.5
  7000   8.4  47.1  285   6  3  10.3   5.6 |   9.4  48.9  275   5  3  10.0   5.5
  6750   9.2  48.6  280   6  3   9.6   5.3 |  10.1  50.2  275   5  3   9.2   5.0
  6500   9.9  49.8  280   6  3  10.5   5.8 |  10.8  51.4  270   5  3   9.9   5.4
  6250  10.8  51.4  280   6  3  11.7   6.4 |  11.6  52.9  270   5  3  10.8   5.9
  6000  11.6  52.9  280   6  3  10.4   5.7 |  12.4  54.3  270   5  3  10.2   5.6
  5750  12.4  54.3  275   6  3  12.2   6.7 |  13.1  55.6  265   5  3   9.8   5.4
  5500  13.5  56.3  275   6  3  16.3   8.9 |  13.9  57.0  270   5  3  10.1   5.6
  5250  14.7  58.5  280   6  3  15.8   8.7 |  14.7  58.5  270   5  3  10.5   5.7
  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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