Soaring Guidance
Issued by NWS Grand Junction, CO

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392
UXUS97 KGJT 031255
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0555 MST Wednesday, February 3, 2016

This forecast is for Wednesday, February 3, 2016:

If the trigger temperature of 26.1 F/-3.3 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 326 ft/min (1.7 m/s)
   Maximum height of thermals.................. 11289 ft MSL (6450 ft AGL)

Forecast maximum temperature................... 28.0 F/-2.7 C
Time of trigger temperature.................... 1230 MST
Time of overdevelopment........................ None
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................. 5976 ft MSL (1137 ft AGL)
Thermal soaring outlook for Thursday 02/04..... Poor

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

Remarks...

Sunrise/Sunset.................... 07:19:07 / 17:35:47 MST
Total possible sunshine........... 10 hr 16 min 41 sec (616 min 41 sec)
Altitude of sun at 12:27:48 MST... 34.42 degrees

Upper air data from rawinsonde observation taken on 02/03/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 10610 ft MSL (5771 ft AGL)
Lifted condensation level....... 10760 ft MSL (5920 ft AGL)
Lifted index.................... +9.7
K index......................... -15.2

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  -50.7 -59.3   290   25   13  -0.6  -0.3  122.8 253.1    70.2      M    M
 45000  -48.2 -54.8   300   36   19   1.4   0.8  102.0 215.6    62.5      M    M
 40000  -47.7 -53.9   305   34   18   0.5   0.3   78.1 172.5    51.5      M    M
 38000  -47.7 -53.9   310   39   20  -6.6  -3.6   69.2 156.6    47.0      M    M
 36000  -49.3 -56.7   310   44   23  -0.7  -0.4   58.1 136.5    40.8      M    M
 34000  -52.4 -62.3   310   50   26  -4.9  -2.7   45.0 113.1    32.8      M    M
 32000  -52.4 -62.3   310   44   22   3.6   2.0   36.6  97.9    27.7      M    M
 30000  -53.1 -63.6   315   45   23 -13.7  -7.5   26.6  80.0    21.2      M    M
 29000  -55.0 -67.0   305   46   24 -11.9  -6.5   20.1  68.2    16.6      M    M
 28000  -54.7 -66.5   305   46   24   5.7   3.1   16.5  61.6    14.1      M    M
 27000  -53.0 -63.4   305   45   23   5.7   3.1   14.9  58.8    13.1      M    M
 26000  -50.9 -59.6   305   45   23   8.9   4.9   13.9  57.0    12.5      M    M
 25000  -48.2 -54.8   305   45   23   8.9   4.9   13.7  56.6    12.4      M    M
 24000  -45.6 -50.1   305   43   22   8.9   4.9   13.2  55.8    12.3      M    M
 23000  -42.9 -45.2   310   42   22   8.7   4.7   13.0  55.3    12.2      M    M
 22000  -40.4 -40.7   315   46   24   8.8   4.8   12.5  54.6    12.0      M    M
 21000  -37.7 -35.9   315   44   22   8.8   4.8   12.1  53.8    11.8      M    M
 20000  -35.1 -31.2   315   41   21   8.9   4.9   11.8  53.3    11.7      M    M
 19500  -33.8 -28.8   315   40   21   8.9   4.9   11.6  53.0    11.6      M    M
 19000  -32.5 -26.5   315   39   20   8.9   4.9   11.5  52.6    11.6      M    M
 18500  -31.1 -24.0   320   38   19   8.9   4.9   11.3  52.4    11.5      M    M
 18000  -29.8 -21.6   320   36   19   8.9   4.9   11.2  52.2    11.5      M    M
 17500  -28.6 -19.5   320   35   18   7.7   4.2   10.9  51.7    11.3      M    M
 17000  -27.4 -17.3   325   35   18   7.8   4.3   10.6  51.0    11.1      M    M
 16500  -25.6 -14.1   330   34   17   7.1   3.9   10.1  50.2    10.8      M    M
 16000  -25.0 -13.0   330   34   17   2.4   1.3    9.2  48.5    10.0      M    M
 15500  -25.2 -13.4   330   36   19  -3.8  -2.1    7.3  45.2     8.4      M    M
 15000  -25.6 -14.1   330   37   19  -3.9  -2.1    5.1  41.3     6.5      M    M
 14500  -25.8 -14.4   330   30   16   2.5   1.3    3.4  38.1     5.0      M    M
 14000  -25.5 -13.9   325   24   13   2.4   1.3    2.1  35.8     3.8      M    M
 13500  -25.1 -13.2   330   21   11   2.7   1.5    0.9  33.6     2.8      M    M
 13000  -24.7 -12.5   335   17    9   2.9   1.6   -0.3  31.5     1.7      M    M
 12500  -24.3 -11.7   345   14    7   4.7   2.6   -1.4  29.4     0.6      M    M
 12000  -23.2  -9.8   355   11    6   8.4   4.6   -1.7  28.9     0.3      M    M
 11500  -21.9  -7.4   355   11    6   8.4   4.6   -2.0  28.4     0.1      M    M
 11000  -20.7  -5.3   355   11    6   8.4   4.6   -2.2  28.0    -0.1    493  2.5
 10500  -19.4  -2.9   360   11    6   8.4   4.6   -2.4  27.6    -0.3    441  2.2
 10250  -18.8  -1.8   360   11    6   8.4   4.6   -2.5  27.4    -0.4    414  2.1
 10000  -18.2  -0.8   360   11    6   8.4   4.6   -2.6  27.3    -0.5    388  2.0
  9750  -17.6   0.3   360   11    5   8.4   4.6   -2.7  27.1    -0.6    362  1.8
  9500  -16.9   1.6   360   10    5   8.4   4.6   -2.8  26.9    -0.7    336  1.7
  9250  -16.3   2.7   355    9    5   8.4   4.6   -2.9  26.8    -0.8    310  1.6
  9000  -15.7   3.7   355    8    4   8.4   4.6   -3.0  26.6    -0.9    284  1.4
  8750  -15.1   4.8   355    7    4   8.4   4.6   -3.1  26.4    -1.0    258  1.3
  8500  -14.4   6.1   360    6    3   8.4   4.6   -3.2  26.2    -1.1    231  1.2
  8250  -13.8   7.2   005    4    2   8.4   4.6   -3.3  26.0    -1.2    205  1.0
  8000  -13.2   8.2   015    3    2   8.4   4.6   -3.4  25.9    -1.3    179  0.9
  7750  -12.6   9.3   015    3    1   8.4   4.6   -3.5  25.7    -1.4    153  0.8
  7500  -11.9  10.6   020    3    1   8.4   4.6   -3.6  25.5    -1.6    127  0.6
  7250  -11.3  11.7   025    2    1   8.4   4.6   -3.7  25.3    -1.7    101  0.5
  7000  -10.7  12.7   030    2    1   8.4   4.6   -3.8  25.1    -1.8     75  0.4
  6750  -10.1  13.8   015    2    1   8.7   4.8   -3.9  24.9    -1.9     49  0.2
  6500   -9.4  15.1   350    1    1   7.6   4.1   -4.1  24.7    -2.0     22  0.1
  6250   -9.0  15.8   320    1    1   4.4   2.4   -4.3  24.2    -2.3      2  0.0
  6000   -8.8  16.2   300    2    1   2.4   1.3   -4.8  23.3    -2.8      M    M
  5750   -8.5  16.7   295    2    1   5.0   2.7   -5.3  22.4    -3.3      M    M
  5500   -8.3  17.1   295    2    1  -5.3  -2.9   -5.9  21.4    -3.9      M    M
  5250   -9.1  15.6   290    2    1  -6.7  -3.7   -7.4  18.7    -5.4      M    M
  5000   -8.8  16.2   290    2    1  13.6   7.4   -7.8  17.9    -5.8      M    M

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

           02/03/2016 at 0800 MST          |       02/03/2016 at 1100 MST
                                           |
K index... -5.2  LI... +280.1              | K index... -5.2  LI... +279.0
CAPE... 0.0  CIN... -0.0                   | CAPE... 0.0  CIN... -0.9
                                           |
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 -50.4 -58.7  295  23 12   1.4   0.8 | -50.5 -58.9  295  25 13   1.0   0.6
 45000 -48.3 -54.9  295  28 14   1.4   0.8 | -48.9 -56.0  300  32 16   1.0   0.6
 40000 -48.5 -55.3  315  35 18  -0.5  -0.3 | -49.8 -57.6  320  38 20  -0.9  -0.5
 38000 -48.8 -55.8  320  39 20  -0.7  -0.4 | -50.4 -58.7  330  42 22  -0.8  -0.4
 36000 -49.6 -57.3  320  42 21  -1.4  -0.8 | -50.4 -58.7  335  47 24   0.0   0.0
 34000 -50.5 -58.9  325  44 23  -1.4  -0.8 | -50.4 -58.7  340  52 27   0.0   0.0
 32000 -50.9 -59.6  325  46 24  -0.2  -0.1 | -50.2 -58.4  340  56 29   0.7   0.4
 30000 -51.0 -59.8  325  49 25  -0.2  -0.1 | -49.7 -57.5  345  58 30   0.7   0.4
 29000 -51.0 -59.8  325  50 26   0.7   0.4 | -49.4 -56.9  345  58 30   2.3   1.3
 28000 -50.7 -59.3  325  50 26   0.9   0.5 | -48.8 -55.8  345  57 29   2.1   1.2
 27000 -50.5 -58.9  320  50 26   0.9   0.5 | -48.1 -54.6  340  56 29   2.1   1.2
 26000 -50.2 -58.4  320  50 26   0.3   0.2 | -47.5 -53.5  340  55 28   2.6   1.5
 25000 -48.5 -55.3  320  50 26   7.1   3.9 | -46.3 -51.3  340  53 27   4.2   2.3
 24000 -46.4 -51.5  320  50 26   7.1   3.9 | -45.0 -49.0  340  52 27   4.2   2.3
 23000 -44.3 -47.7  315  50 26   7.1   3.9 | -43.8 -46.8  340  50 26   5.1   2.8
 22000 -41.2 -42.2  320  50 26   8.3   4.6 | -41.8 -43.2  340  49 25   6.9   3.8
 21000 -38.7 -37.7  320  51 26   8.3   4.6 | -39.7 -39.5  340  48 24   6.9   3.8
 20000 -36.4 -33.5  320  50 26   6.6   3.6 | -37.6 -35.7  340  46 24   7.2   3.9
 19500 -35.4 -31.7  325  49 25   6.7   3.6 | -36.6 -33.9  340  45 23   7.1   3.9
 19000 -34.4 -29.9  325  48 25   6.7   3.7 | -35.5 -31.9  340  44 23   7.1   3.9
 18500 -33.4 -28.1  325  47 24   6.6   3.6 | -33.9 -29.0  340  42 22   7.1   3.9
 18000 -32.4 -26.3  330  46 24   6.4   3.5 | -32.9 -27.2  340  41 21   6.0   3.3
 17500 -31.5 -24.7  330  44 23   6.0   3.3 | -32.0 -25.6  340  39 20   5.5   3.0
 17000 -30.6 -23.1  330  42 21   6.0   3.3 | -31.2 -24.2  340  38 20   5.0   2.8
 16500 -29.7 -21.5  330  39 20   6.0   3.3 | -30.6 -23.1  340  36 18   3.9   2.2
 16000 -28.8 -19.8  330  36 19   6.2   3.4 | -30.0 -22.0  340  33 17   4.0   2.2
 15500 -28.0 -18.4  330  33 17   3.8   2.1 | -29.5 -21.1  340  30 16   3.5   1.9
 15000 -27.5 -17.5  330  30 16   3.9   2.1 | -28.9 -20.0  345  27 14   3.1   1.7
 14500 -26.9 -16.4  330  27 14   3.6   2.0 | -28.1 -18.6  345  25 13   8.0   4.4
 14000 -26.4 -15.5  330  24 13   3.5   1.9 | -27.0 -16.6  350  23 12   7.5   4.1
 13500 -25.8 -14.4  325  22 11   5.6   3.1 | -25.9 -14.6  350  21 11   8.0   4.4
 13000 -24.9 -12.8  330  19 10   5.9   3.3 | -24.7 -12.5  350  20 10   8.0   4.4
 12500 -23.9 -11.0  330  17  9   6.9   3.8 | -23.5 -10.3  350  19 10   7.9   4.3
 12000 -22.9  -9.2  335  15  8   7.0   3.9 | -22.3  -8.1  345  18  9   7.9   4.4
 11500 -21.8  -7.2  340  14  7   7.3   4.0 | -21.2  -6.2  345  17  9   7.6   4.2
 11000 -20.7  -5.3  350  13  7   7.2   4.0 | -20.0  -4.0  340  15  8   7.7   4.2
 10500 -19.6  -3.3  360  13  7   7.9   4.3 | -18.8  -1.8  340  13  7   8.1   4.4
 10250 -19.0  -2.2  360  13  7   8.4   4.6 | -18.2  -0.8  340  12  6   8.5   4.7
 10000 -18.4  -1.1  005  13  7   6.2   3.4 | -17.6   0.3  340  12  6   6.6   3.6
  9750 -18.0  -0.4  005  13  7   5.7   3.1 | -17.2   1.0  340  11  6   6.1   3.4
  9500 -17.4   0.7  005  13  7   9.2   5.1 | -16.7   1.9  340  10  5   8.2   4.5
  9250 -16.7   1.9  010  13  7  10.9   6.0 | -16.1   3.0  340   9  5   8.1   4.4
  9000 -15.9   3.4  010  13  7   7.8   4.3 | -15.5   4.1  340   8  4   5.8   3.2
  8750 -15.5   4.1  010  12  6   5.3   2.9 | -15.2   4.6  345   7  4   4.9   2.7
  8500 -15.1   4.8  010  11  6   6.9   3.8 | -14.7   5.5  345   6  3   6.4   3.5
  8250 -14.5   5.9  010  10  5   6.5   3.6 | -14.3   6.3  340   5  3   6.1   3.3
  8000 -14.1   6.6  010   8  4   5.3   2.9 | -13.9   7.0  335   4  2   5.3   2.9
  7750 -13.8   7.2  005   7  3   4.7   2.6 | -13.5   7.7  325   3  2   5.7   3.1
  7500 -13.4   7.9  005   4  2   4.4   2.4 | -13.0   8.6  295   2  1   6.2   3.4
  7250 -13.1   8.4  010   2  1   4.9   2.7 | -12.6   9.3  260   2  1   6.4   3.5
  7000 -12.7   9.1  030   1  0   5.4   3.0 | -12.1  10.2  240   3  1   6.1   3.3
  6750 -12.3   9.9  150   1  0   5.6   3.0 | -11.6  11.1  230   4  2   6.8   3.7
  6500 -11.9  10.6  160   2  1   6.4   3.5 | -11.1  12.0  225   4  2   9.0   4.9
  6250 -11.4  11.5  165   2  1   6.9   3.8 | -10.4  13.3  225   4  2  10.1   5.5
  6000 -10.9  12.4  170   2  1   6.3   3.4 |  -9.6  14.7  225   4  2   9.3   5.1
  5750 -10.4  13.3  170   2  1   8.5   4.7 |  -8.9  16.0  225   4  2  12.8   7.0
  5500  -9.5  14.9  170   2  1  13.9   7.6 |  -7.7  18.1  225   4  2  19.9  10.9
  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

           02/03/2016 at 1400 MST          |       02/03/2016 at 1700 MST
                                           |
K index... -14.4  LI... +279.6             | K index... -19.6  LI... +280.3
CAPE... 0.0  CIN... -1.4                   | 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 -51.3 -60.3  300  25 13   0.9   0.5 | -51.9 -61.4  300  25 13   0.3   0.1
 45000 -49.9 -57.8  310  35 18   0.9   0.5 | -51.5 -60.7  325  38 20   0.3   0.1
 40000 -50.8 -59.4  325  42 22  -1.0  -0.5 | -53.4 -64.1  335  50 26  -1.6  -0.9
 38000 -51.4 -60.5  330  45 23  -0.9  -0.5 | -54.4 -65.9  335  56 29  -2.2  -1.2
 36000 -51.9 -61.4  340  55 28  -0.9  -0.5 | -56.0 -68.8  345  72 37  -2.7  -1.5
 34000 -52.5 -62.5  345  65 33  -0.9  -0.5 | -57.6 -71.7  350  90 47  -2.7  -1.5
 32000 -51.7 -61.1  350  77 40   2.4   1.3 | -54.8 -66.6  355 103 53   7.2   3.9
 30000 -50.2 -58.4  360  88 45   2.5   1.4 | -50.5 -58.9  355 112 58   7.1   3.9
 29000 -49.3 -56.7  360  89 46   3.9   2.1 | -48.1 -54.6  360 113 58   8.4   4.6
 28000 -48.1 -54.6  355  85 44   3.9   2.1 | -45.6 -50.1  360 113 58   8.5   4.6
 27000 -47.0 -52.6  355  80 41   3.9   2.1 | -43.1 -45.6  360 112 58   8.5   4.7
 26000 -45.8 -50.4  355  76 39   4.1   2.3 | -40.9 -41.6  360 109 56   3.4   1.9
 25000 -44.5 -48.1  355  70 36   4.3   2.3 | -39.7 -39.5  355  96 49   3.8   2.1
 24000 -43.2 -45.8  355  64 33   4.3   2.3 | -38.6 -37.5  350  83 43   3.8   2.1
 23000 -41.9 -43.4  355  59 30   6.1   3.4 | -37.5 -35.5  350  71 37   2.6   1.4
 22000 -39.7 -39.5  360  57 29   7.2   4.0 | -36.8 -34.2  345  62 32   2.5   1.4
 21000 -37.6 -35.7  360  55 28   7.2   4.0 | -36.0 -32.8  345  54 28   2.6   1.4
 20000 -35.5 -31.9  360  52 27   6.2   3.4 | -34.6 -30.3  345  48 25   7.3   4.0
 19500 -34.6 -30.3  360  51 26   6.3   3.4 | -33.5 -28.3  345  47 24   7.3   4.0
 19000 -33.6 -28.5  360  49 25   6.3   3.4 | -32.4 -26.3  345  45 23   7.3   4.0
 18500 -32.2 -26.0  360  47 24   6.3   3.4 | -30.8 -23.4  350  43 22   7.2   4.0
 18000 -31.3 -24.3  360  45 23   6.3   3.4 | -29.6 -21.3  350  41 21   8.0   4.4
 17500 -30.3 -22.5  355  43 22   6.3   3.4 | -28.5 -19.3  350  40 21   8.0   4.4
 17000 -29.4 -20.9  355  42 22   6.0   3.3 | -27.3 -17.1  350  39 20   7.1   3.9
 16500 -28.6 -19.5  355  41 21   5.7   3.1 | -26.3 -15.3  350  37 19   6.7   3.7
 16000 -27.7 -17.9  355  41 21   5.4   3.0 | -25.3 -13.5  355  36 19   6.6   3.6
 15500 -27.0 -16.6  355  38 20   4.1   2.2 | -24.3 -11.7  355  35 18   6.5   3.6
 15000 -26.4 -15.5  350  35 18   4.1   2.3 | -23.3  -9.9  355  34 17   6.4   3.5
 14500 -26.0 -14.8  350  31 16   1.7   0.9 | -22.5  -8.5  355  33 17   5.4   3.0
 14000 -25.7 -14.3  350  26 13   1.7   0.9 | -21.6  -6.9  355  32 16   5.4   2.9
 13500 -25.1 -13.2  350  22 11   7.1   3.9 | -21.1  -6.0  355  31 16   1.7   0.9
 13000 -24.1 -11.4  350  19 10   6.6   3.6 | -20.9  -5.6  355  29 15   2.0   1.1
 12500 -22.9  -9.2  350  18  9   9.0   4.9 | -20.6  -5.1  350  26 13   1.2   0.7
 12000 -21.6  -6.9  350  17  9   8.8   4.8 | -20.5  -4.9  350  22 11   2.1   1.1
 11500 -20.3  -4.5  345  16  8   9.3   5.1 | -19.6  -3.3  350  18  9   8.4   4.6
 11000 -18.9  -2.0  340  16  8   8.9   4.9 | -18.4  -1.1  350  14  7   8.1   4.4
 10500 -17.7   0.1  335  14  7   7.4   4.1 | -17.2   1.0  345  12  6   8.2   4.5
 10250 -17.1   1.2  335  14  7   7.9   4.4 | -16.6   2.1  340  11  6   8.7   4.8
 10000 -16.6   2.1  330  13  7   6.3   3.5 | -16.0   3.2  335  10  5   6.6   3.6
  9750 -16.2   2.8  330  12  6   6.0   3.3 | -15.6   3.9  335  10  5   6.9   3.8
  9500 -15.6   3.9  325  11  6   7.5   4.1 | -14.9   5.2  330   9  5   9.7   5.3
  9250 -15.1   4.8  315  10  5   7.1   3.9 | -14.2   6.4  325   9  4   8.6   4.7
  9000 -14.6   5.7  310  10  5   6.1   3.4 | -13.7   7.3  320   8  4   6.6   3.6
  8750 -14.2   6.4  305   9  5   6.1   3.3 | -13.2   8.2  315   8  4   6.4   3.5
  8500 -13.7   7.3  300   9  4   6.9   3.8 | -12.7   9.1  310   7  4   7.9   4.3
  8250 -13.1   8.4  290   8  4   7.0   3.8 | -12.1  10.2  305   6  3   7.2   4.0
  8000 -12.6   9.3  285   8  4   6.9   3.8 | -11.6  11.1  300   6  3   6.6   3.6
  7750 -12.1  10.2  280   7  4   7.3   4.0 | -11.1  12.0  295   5  3   6.6   3.6
  7500 -11.5  11.3  275   7  3   7.6   4.1 | -10.6  12.9  285   5  3   6.1   3.3
  7250 -11.0  12.2  270   6  3   6.9   3.8 | -10.2  13.6  275   4  2   5.7   3.1
  7000 -10.5  13.1  265   5  3   6.9   3.8 |  -9.7  14.5  260   4  2   5.7   3.1
  6750 -10.1  13.8  255   5  2   6.3   3.5 |  -9.3  15.3  245   3  2   5.6   3.1
  6500  -9.6  14.7  250   4  2   8.4   4.6 |  -8.9  16.0  230   3  1   6.6   3.6
  6250  -8.8  16.2  250   4  2  10.9   6.0 |  -8.4  16.9  220   3  1   7.5   4.1
  6000  -8.1  17.4  250   4  2   9.6   5.3 |  -7.9  17.8  210   3  1   7.5   4.1
  5750  -7.3  18.9  250   4  2  12.5   6.8 |  -7.3  18.9  205   3  2   9.1   5.0
  5500  -6.2  20.8  250   4  2  18.8  10.3 |  -6.6  20.1  205   3  1  10.9   6.0
  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
________________________________________________________________________________

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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