Soaring Guidance
Issued by NWS Grand Junction, CO

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550
UXUS97 KGJT 041245
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0545 MST Sunday, December 4, 2016

This forecast is for Sunday, December 4, 2016:

If the trigger temperature of 39.9 F/4.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 245 ft/min (1.2 m/s)
   Maximum height of thermals.................. 8550 ft MSL (3711 ft AGL)

Forecast maximum temperature................... 39.0 F/4.3 C
Time of trigger temperature.................... 1400 MST
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................. 6620 ft MSL (1780 ft AGL)
Thermal soaring outlook for Monday 12/05....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:17:43 / 16:51:34 MST
Total possible sunshine........... 9 hr 33 min 51 sec (573 min 51 sec)
Altitude of sun at 12:04:44 MST... 28.58 degrees

Upper air data from rawinsonde observation taken on 12/04/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 18356 ft MSL (13517 ft AGL)
Lifted condensation level....... 11115 ft MSL (6276 ft AGL)
Lifted index.................... +15.6
K index......................... -6.7

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  -62.1 -79.8   295   62   32  -6.9  -3.8   99.3 210.7    54.1      M    M
 45000  -58.8 -73.8   295   73   38   2.6   1.4   79.8 175.7    46.1      M    M
 40000  -53.3 -63.9   290   55   28   2.7   1.5   65.2 149.3    39.8      M    M
 38000  -53.8 -64.8   300   49   25  -5.7  -3.1   54.3 129.8    33.8      M    M
 36000  -53.8 -64.8   320   68   35  -7.3  -4.0   45.8 114.4    28.8      M    M
 34000  -54.2 -65.6   325   75   38   4.8   2.7   36.7  98.1    23.2      M    M
 32000  -49.6 -57.3   325   72   37   8.7   4.8   35.0  94.9    22.6      M    M
 30000  -44.2 -47.6   320   69   36   9.3   5.1   34.3  93.8    22.7      M    M
 29000  -41.4 -42.5   320   68   35   9.5   5.2   34.1  93.4    22.8      M    M
 28000  -39.4 -38.9   320   67   34   7.2   3.9   33.0  91.3    22.2      M    M
 27000  -36.9 -34.4   325   66   34   8.3   4.6   32.3  90.2    22.0      M    M
 26000  -34.4 -29.9   325   65   33   8.4   4.6   31.8  89.3    21.9      M    M
 25000  -32.4 -26.3   325   64   33   6.1   3.3   30.7  87.2    21.2      M    M
 24000  -30.7 -23.3   325   62   32   5.6   3.1   29.2  84.6    20.3      M    M
 23000  -28.8 -19.8   325   59   30   6.3   3.5   27.9  82.1    19.4      M    M
 22000  -26.7 -16.1   325   56   29   7.5   4.1   26.9  80.4    18.8      M    M
 21000  -24.5 -12.1   320   52   27   7.6   4.2   26.1  78.9    18.4      M    M
 20000  -21.6  -6.9   320   49   25   7.6   4.2   25.1  77.2    17.8      M    M
 19500  -20.5  -4.9   320   47   24   7.6   4.2   24.7  76.5    17.6      M    M
 19000  -19.3  -2.7   320   44   23   7.7   4.2   24.3  75.8    17.3      M    M
 18500  -18.3  -0.9   320   41   21   5.8   3.2   23.8  74.9    17.0      M    M
 18000  -17.4   0.7   325   34   18   6.5   3.5   23.1  73.6    16.5      M    M
 17500  -16.4   2.5   325   35   18   6.9   3.8   22.6  72.7    16.2      M    M
 17000  -15.3   4.5   320   36   18   7.0   3.8   22.1  71.8    15.8      M    M
 16500  -14.3   6.3   320   36   19   7.0   3.8   21.7  71.0    15.5      M    M
 16000  -13.3   8.1   320   37   19   7.0   3.8   21.2  70.2    15.2      M    M
 15500  -12.3   9.9   325   37   19   6.4   3.5   20.7  69.3    14.8      M    M
 15000  -11.4  11.5   325   38   20   6.0   3.3   20.1  68.1    14.3      M    M
 14500  -10.5  13.1   330   38   20   6.0   3.3   19.4  67.0    13.8      M    M
 14000   -9.6  14.7   330   39   20   5.7   3.1   18.8  65.9    13.3      M    M
 13500   -9.2  15.4   325   34   18  -0.3  -0.2   17.7  63.8    12.3      M    M
 13000   -8.4  16.9   325   30   15  10.5   5.8   16.9  62.4    11.7      M    M
 12500   -7.0  19.4   320   26   13  10.9   6.0   16.9  62.4    11.7      M    M
 12000   -6.2  20.8   315   22   11  -2.8  -1.6   16.1  61.0    11.1      M    M
 11500   -5.9  21.4   305   19   10   3.6   2.0   14.8  58.6    10.0      M    M
 11000   -6.6  20.1   295   16    8  -7.2  -4.0   12.4  54.4     7.9      M    M
 10500   -6.3  20.7   280   15    8   6.1   3.3   11.2  52.1     6.7      M    M
 10250   -5.9  21.4   270   14    7   8.4   4.6   10.9  51.5     6.5      M    M
 10000   -5.7  21.7   260   14    7 -13.4  -7.4   10.3  50.6     6.0      M    M
  9750   -7.7  18.1   260   11    6 -24.3 -13.3    7.5  45.4     3.2      M    M
  9500   -8.6  16.5   255    8    4  -0.2  -0.1    5.8  42.5     1.6      M    M
  9250   -8.2  17.2   250    5    3   5.7   3.1    5.4  41.7     1.2      M    M
  9000   -7.9  17.8   225    2    1   4.2   2.3    5.0  41.0     0.8      M    M
  8750   -7.6  18.3   170    3    2   4.6   2.5    4.6  40.2     0.4      M    M
  8500   -7.3  18.9   150    5    3   4.5   2.5    4.2  39.5    -0.0    244  1.2
  8250   -6.9  19.6   145    8    4   4.3   2.4    3.8  38.8    -0.4    227  1.2
  8000   -6.6  20.1   140   11    5   5.2   2.9    3.4  38.0    -0.8    210  1.1
  7750   -6.2  20.8   145   12    6   6.9   3.8    3.1  37.5    -1.1    189  1.0
  7500   -5.6  21.9   150   14    7   7.2   4.0    2.9  37.2    -1.3    165  0.8
  7250   -5.1  22.8   150   15    8   7.0   3.8    2.7  36.8    -1.5    142  0.7
  7000   -4.7  23.5   155   17    9   2.8   1.6    2.4  36.2    -1.8    122  0.6
  6750   -4.6  23.7   150   16    8   1.9   1.0    1.7  35.0    -2.5    112  0.6
  6500   -4.5  23.9   150   15    8  -3.2  -1.8    1.0  33.9    -3.1    103  0.5
  6250   -4.9  23.2   145   14    7  -2.6  -1.4   -0.1  31.7    -4.3    108  0.5
  6000   -4.7  23.5   135   13    7   7.5   4.1   -0.6  30.9    -4.8     92  0.5
  5750   -4.0  24.8   130   12    6   8.0   4.4   -0.7  30.7    -4.9     66  0.3
  5500   -3.4  25.9   125   11    5   9.3   5.1   -0.9  30.5    -5.0     41  0.2
  5250   -2.8  27.0   120    9    5   3.6   2.0   -1.0  30.2    -5.2     15  0.1
  5000   -3.3  26.1   110    8    4 -18.8 -10.3   -2.2  28.0    -6.4     22  0.1

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

           12/04/2016 at 0800 MST          |       12/04/2016 at 1100 MST
                                           |
K index... -2.6  LI... +6.6                | K index... +0.9  LI... +5.6
CAPE... 0.0  CIN... M                      | 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 -63.0 -81.4  295  61 31   2.7   1.5 | -62.8 -81.0  290  57 30   2.6   1.4
 45000 -58.9 -74.0  295  65 33   2.2   1.2 | -58.9 -74.0  290  58 30   2.2   1.2
 40000 -57.0 -70.6  300  58 30   1.3   0.7 | -56.8 -70.2  300  49 25   1.4   0.7
 38000 -56.3 -69.3  305  57 29   0.7   0.4 | -56.2 -69.2  300  49 25   0.6   0.3
 36000 -55.9 -68.6  315  59 30   0.7   0.4 | -55.8 -68.4  305  54 28   0.6   0.3
 34000 -54.4 -65.9  320  60 31   9.0   4.9 | -54.4 -65.9  305  58 30   8.6   4.7
 32000 -49.1 -56.4  315  58 30   8.8   4.8 | -49.4 -56.9  305  53 27   8.4   4.6
 30000 -44.0 -47.2  315  56 29   8.2   4.5 | -44.3 -47.7  300  50 25   8.5   4.7
 29000 -41.5 -42.7  320  56 29   8.2   4.5 | -41.7 -43.1  300  50 26   8.6   4.7
 28000 -39.0 -38.2  320  57 29   8.2   4.5 | -39.1 -38.4  305  50 26   8.6   4.7
 27000 -36.6 -33.9  320  57 29   7.6   4.2 | -36.6 -33.9  310  51 26   7.9   4.3
 26000 -34.6 -30.3  320  57 29   6.7   3.7 | -34.5 -30.1  310  51 26   7.0   3.8
 25000 -32.5 -26.5  320  57 29   6.7   3.7 | -32.4 -26.3  310  50 26   7.0   3.8
 24000 -30.5 -22.9  325  56 29   6.8   3.7 | -30.3 -22.5  310  50 26   7.1   3.9
 23000 -28.3 -18.9  325  54 28   7.8   4.3 | -27.9 -18.2  310  49 25   8.1   4.5
 22000 -26.0 -14.8  320  51 26   7.8   4.3 | -25.5 -13.9  310  48 25   8.1   4.5
 21000 -23.6 -10.5  320  47 24   7.2   3.9 | -23.1  -9.6  310  47 24   7.4   4.1
 20000 -21.7  -7.1  315  44 22   6.5   3.6 | -20.6  -5.1  305  44 23   6.8   3.7
 19500 -20.3  -4.5  315  41 21   6.5   3.6 | -19.5  -3.1  305  42 22   6.8   3.7
 19000 -19.3  -2.7  310  39 20   6.5   3.6 | -18.5  -1.3  305  41 21   6.9   3.8
 18500 -18.3  -0.9  310  37 19   6.4   3.5 | -17.6   0.3  305  40 21   5.7   3.1
 18000 -17.4   0.7  310  35 18   6.4   3.5 | -16.8   1.8  305  40 21   5.6   3.1
 17500 -16.4   2.5  310  32 17   6.8   3.8 | -16.0   3.2  305  40 21   5.7   3.1
 17000 -15.3   4.5  310  32 16   7.8   4.3 | -15.1   4.8  305  40 20   5.7   3.1
 16500 -14.1   6.6  310  31 16   7.8   4.3 | -14.2   6.4  305  40 20   5.6   3.1
 16000 -12.9   8.8  310  31 16   8.3   4.6 | -13.2   8.2  305  38 20   7.9   4.3
 15500 -11.7  10.9  310  31 16   8.3   4.6 | -12.0  10.4  300  37 19   7.7   4.2
 15000 -10.5  13.1  315  31 16   7.4   4.0 | -10.9  12.4  300  35 18   7.4   4.0
 14500  -9.4  15.1  315  30 15   7.2   4.0 |  -9.8  14.4  300  34 17   7.4   4.0
 14000  -8.4  16.9  315  29 15   6.6   3.6 |  -8.7  16.3  300  32 17   7.8   4.3
 13500  -7.5  18.5  315  27 14   6.1   3.4 |  -7.5  18.5  305  31 16   8.0   4.4
 13000  -6.6  20.1  315  26 13   5.2   2.8 |  -6.3  20.7  305  29 15   7.3   4.0
 12500  -6.0  21.2  315  24 12   3.9   2.1 |  -5.3  22.5  305  27 14   6.4   3.5
 12000  -5.4  22.3  315  22 12   3.0   1.7 |  -4.4  24.1  305  25 13   4.4   2.4
 11500  -5.1  22.8  315  21 11   1.5   0.8 |  -4.1  24.6  300  22 11   1.3   0.7
 11000  -4.9  23.2  315  19 10  -0.1  -0.0 |  -4.0  24.8  300  19 10  -0.3  -0.2
 10500  -5.2  22.6  315  17  9  -2.4  -1.3 |  -4.3  24.3  295  16  8  -2.5  -1.4
 10250  -5.4  22.3  310  16  8  -2.7  -1.5 |  -4.5  23.9  290  14  7  -2.8  -1.5
 10000  -5.6  21.9  310  15  8  -1.5  -0.8 |  -4.7  23.5  290  13  7  -1.3  -0.7
  9750  -5.7  21.7  305  13  7  -3.3  -1.8 |  -4.8  23.4  280  11  6  -1.9  -1.0
  9500  -6.1  21.0  300  11  6  -6.0  -3.3 |  -5.0  23.0  275  10  5  -3.8  -2.1
  9250  -6.5  20.3  290   9  5  -4.3  -2.3 |  -5.2  22.6  265   8  4  -2.5  -1.4
  9000  -6.7  19.9  280   7  4  -0.1  -0.0 |  -5.3  22.5  250   8  4   0.7   0.4
  8750  -6.5  20.3  270   6  3   3.5   1.9 |  -5.1  22.8  240   7  4   2.5   1.4
  8500  -6.3  20.7  255   5  2   3.7   2.0 |  -5.0  23.0  230   6  3   1.5   0.8
  8250  -6.0  21.2  235   4  2   4.4   2.4 |  -4.8  23.4  215   6  3   3.4   1.9
  8000  -5.6  21.9  215   4  2   5.1   2.8 |  -4.5  23.9  210   7  3   5.3   2.9
  7750  -5.3  22.5  200   5  3   5.8   3.2 |  -4.1  24.6  205   7  4   5.6   3.1
  7500  -4.8  23.4  190   6  3   6.2   3.4 |  -3.7  25.3  200   7  4   5.6   3.1
  7250  -4.4  24.1  185   7  4   4.3   2.4 |  -3.3  26.1  195   8  4   3.4   1.9
  7000  -4.1  24.6  180   8  4   3.5   1.9 |  -3.1  26.4  185   8  4   2.4   1.3
  6750  -3.8  25.2  175   9  5   3.9   2.1 |  -2.9  26.8  180   9  5   2.5   1.4
  6500  -3.6  25.5  170  10  5  -0.1  -0.1 |  -2.7  27.1  175   9  5   3.2   1.8
  6250  -3.8  25.2  165   9  5  -3.4  -1.9 |  -2.5  27.5  175   8  4   4.5   2.5
  6000  -4.0  24.8  160   9  4  -1.8  -1.0 |  -2.2  28.0  175   7  3   3.2   1.7
  5750  -4.2  24.4  155   8  4  -4.7  -2.6 |  -1.9  28.6  170   6  3   7.4   4.0
  5500  -4.9  23.2  130   6  3 -14.0  -7.7 |  -1.0  30.2  170   5  2  18.1   9.9
  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

           12/04/2016 at 1400 MST          |       12/04/2016 at 1700 MST
                                           |
K index... +8.9  LI... +4.9                | K index... +11.0  LI... +5.5
CAPE... 0.0  CIN... -0.6                   | CAPE... 0.0  CIN... -0.1
                                           |
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 -62.6 -80.7  290  52 27   2.4   1.3 | -63.7 -82.7  285  49 25   2.7   1.5
 45000 -58.9 -74.0  290  51 26   2.3   1.3 | -59.4 -74.9  285  49 25   2.4   1.3
 40000 -55.9 -68.6  295  50 26   2.0   1.1 | -56.4 -69.5  290  52 27   2.0   1.1
 38000 -55.2 -67.4  295  52 27  -0.2  -0.1 | -55.6 -68.1  295  53 28   0.2   0.1
 36000 -55.3 -67.5  300  58 30  -0.2  -0.1 | -55.5 -67.9  295  55 28   0.2   0.1
 34000 -54.9 -66.8  300  63 33   8.5   4.7 | -54.8 -66.6  300  56 29   8.5   4.6
 32000 -49.1 -56.4  300  58 30   8.6   4.7 | -49.8 -57.6  295  54 28   8.3   4.6
 30000 -44.0 -47.2  295  54 28   8.0   4.4 | -44.2 -47.6  295  52 27   8.4   4.6
 29000 -41.6 -42.9  295  51 26   8.0   4.4 | -41.7 -43.1  295  51 26   8.4   4.6
 28000 -39.2 -38.6  300  48 25   8.0   4.4 | -39.2 -38.6  300  50 26   8.4   4.6
 27000 -36.8 -34.2  300  46 24   8.0   4.4 | -36.7 -34.1  305  49 25   8.6   4.7
 26000 -34.4 -29.9  300  45 23   8.1   4.4 | -34.0 -29.2  300  45 23   8.7   4.8
 25000 -32.0 -25.6  300  44 23   8.1   4.4 | -31.4 -24.5  300  41 21   8.7   4.8
 24000 -29.5 -21.1  300  43 22   8.0   4.4 | -28.8 -19.8  295  37 19   8.5   4.6
 23000 -27.2 -17.0  300  43 22   7.8   4.3 | -26.6 -15.9  295  37 19   7.2   4.0
 22000 -24.9 -12.8  300  43 22   7.8   4.3 | -24.4 -11.9  290  38 20   7.2   4.0
 21000 -22.6  -8.7  295  43 22   7.3   4.0 | -22.3  -8.1  285  39 20   7.1   3.9
 20000 -20.5  -4.9  295  43 22   7.0   3.8 | -20.2  -4.4  290  40 20   7.0   3.9
 19500 -19.4  -2.9  295  43 22   7.0   3.8 | -19.1  -2.4  290  40 20   7.0   3.9
 19000 -18.4  -1.1  295  43 22   7.0   3.8 | -18.1  -0.6  290  40 20   7.0   3.9
 18500 -17.4   0.7  295  43 22   6.5   3.5 | -17.0   1.4  290  40 21   6.6   3.6
 18000 -16.5   2.3  295  42 22   5.5   3.0 | -16.2   2.8  290  40 21   5.7   3.1
 17500 -15.7   3.7  295  41 21   5.5   3.0 | -15.3   4.5  290  40 21   5.7   3.1
 17000 -14.9   5.2  295  40 21   5.5   3.0 | -14.5   5.9  290  40 21   5.4   2.9
 16500 -14.1   6.6  295  39 20   5.5   3.0 | -13.7   7.3  290  40 20   5.4   2.9
 16000 -13.3   8.1  295  38 20   5.3   2.9 | -13.0   8.6  290  40 20   4.8   2.7
 15500 -12.2  10.0  295  38 20   5.0   2.7 | -12.3   9.9  290  39 20   4.5   2.5
 15000 -11.3  11.7  295  38 19   7.0   3.8 | -11.3  11.7  290  38 20   5.7   3.1
 14500 -10.2  13.6  295  37 19   7.1   3.9 | -10.4  13.3  290  37 19   5.9   3.2
 14000  -9.1  15.6  295  35 18   7.8   4.3 |  -9.6  14.7  290  36 19   6.2   3.4
 13500  -7.9  17.8  290  34 18   8.0   4.4 |  -8.6  16.5  290  34 18   6.4   3.5
 13000  -6.7  19.9  290  33 17   7.1   3.9 |  -7.6  18.3  290  33 17   6.9   3.8
 12500  -5.8  21.6  285  31 16   6.5   3.5 |  -6.5  20.3  285  31 16   7.4   4.1
 12000  -4.8  23.4  285  29 15   5.5   3.0 |  -5.4  22.3  285  30 15   6.4   3.5
 11500  -4.2  24.4  280  26 13   4.6   2.5 |  -4.6  23.7  280  28 15   5.1   2.8
 11000  -3.5  25.7  280  23 12   2.4   1.3 |  -3.9  25.0  275  27 14   3.9   2.1
 10500  -3.5  25.7  275  20 11   0.6   0.3 |  -3.5  25.7  270  25 13   2.7   1.5
 10250  -3.4  25.9  270  19 10   0.6   0.3 |  -3.3  26.1  270  24 12   2.2   1.2
 10000  -3.4  25.9  265  18  9  -0.0  -0.0 |  -3.1  26.4  265  23 12   2.2   1.2
  9750  -3.4  25.9  260  16  8  -0.7  -0.4 |  -2.9  26.8  260  21 11   2.6   1.4
  9500  -3.4  25.9  255  15  8  -0.7  -0.4 |  -2.8  27.0  255  20 10   2.4   1.3
  9250  -3.4  25.9  245  13  7  -0.1  -0.1 |  -2.6  27.3  250  18  9   2.8   1.5
  9000  -3.4  25.9  240  12  6   1.6   0.9 |  -2.4  27.7  250  17  9   3.0   1.6
  8750  -3.2  26.2  235  12  6   2.5   1.4 |  -2.2  28.0  245  15  8   2.4   1.3
  8500  -3.0  26.6  230  11  6   2.5   1.4 |  -2.0  28.4  240  14  7   2.3   1.3
  8250  -2.8  27.0  225  10  5   2.6   1.4 |  -1.8  28.8  235  13  6   2.0   1.1
  8000  -2.6  27.3  220  10  5   2.7   1.5 |  -1.7  28.9  230  12  6   1.8   1.0
  7750  -2.4  27.7  215   9  5   2.8   1.5 |  -1.6  29.1  220  11  5   2.4   1.3
  7500  -2.2  28.0  210   9  5   2.7   1.5 |  -1.4  29.5  215  10  5   2.8   1.5
  7250  -2.0  28.4  210   8  4   2.2   1.2 |  -1.2  29.8  205   9  5   2.8   1.5
  7000  -1.9  28.6  210   7  4   2.3   1.2 |  -1.0  30.2  200   9  4   2.9   1.6
  6750  -1.7  28.9  205   6  3   4.3   2.4 |  -0.7  30.7  190   8  4   3.4   1.8
  6500  -1.3  29.7  210   5  2   7.7   4.2 |  -0.5  31.1  185   7  4   3.9   2.1
  6250  -0.7  30.7  210   4  2   9.0   4.9 |  -0.2  31.6  185   6  3   3.8   2.1
  6000  -0.0  32.0  215   4  2   8.4   4.6 |   0.1  32.2  190   4  2   4.4   2.4
  5750   0.6  33.1  215   4  2   7.9   4.3 |   0.4  32.7  195   3  1   1.8   1.0
  5500   1.1  34.0  220   4  2   7.7   4.2 |   0.3  32.5  205   2  1  -2.2  -1.2
  5250   1.7  35.1  220   4  2   8.0   4.4 |   0.1  32.2  200   1  1  -1.4  -0.8
  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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