Soaring Guidance
Issued by NWS Grand Junction, CO

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UXUS97 KGJT 231223
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Soaring Forecast
National Weather Service Grand Junction, Colorado
0523 MST Monday, November 23, 2020

This forecast is for Monday, November 23, 2020:

If the trigger temperature of 59.4 F/15.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7251 ft MSL (2412 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1500 MST
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6464 ft MSL (1625 ft AGL)
Thermal soaring outlook for Tuesday 11/24...... Poor

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

Remarks...

***ATTENTION Soaring Forecast Users***The National Weather Service in Boulder wants to hear from you.
Please send and email to paul.t.schlatter@noaa.gov and let us know how you use the Soaring Forecast.  Thanks!

Sunrise/Sunset.................... 07:06:56 / 16:54:33 MST
Total possible sunshine........... 9 hr 47 min 37 sec (587 min 37 sec)
Altitude of sun at 12:00:44 MST... 30.33 degrees

Upper air data from rawinsonde observation taken on 11/23/2020 at 0500 MST

Freezing level.................. 10302 ft MSL (5463 ft AGL)
Convective condensation level... 13601 ft MSL (8762 ft AGL)
Lifted condensation level....... 11082 ft MSL (6243 ft AGL)
Lifted index.................... +6.1
K index......................... +11.5

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  -61.1 -78.0   260   60   31   4.1   2.3   99.9 211.7    49.5      M    M
 45000  -61.1 -78.0   255   71   37  -0.4  -0.2   75.0 167.1    37.9      M    M
 40000  -61.7 -79.1   250  108   55   5.7   3.2   50.8 123.4    24.8      M    M
 38000  -58.5 -73.3   250  112   58   6.8   3.7   46.9 116.5    22.9      M    M
 36000  -54.0 -65.2   250  115   59   4.7   2.6   43.8 110.8    21.4      M    M
 34000  -51.5 -60.7   245  111   57   6.8   3.7   39.0 102.3    18.7      M    M
 32000  -47.4 -53.3   245   94   48   6.8   3.7   36.3  97.4    17.2      M    M
 30000  -43.4 -46.1   240   75   39   4.0   2.2   34.1  93.4    16.0      M    M
 29000  -41.5 -42.7   240   72   37   6.0   3.3   32.7  90.8    15.0      M    M
 28000  -38.8 -37.8   240   69   36   9.1   5.0   32.4  90.4    15.1      M    M
 27000  -36.1 -33.0   245   67   34   9.2   5.0   32.1  89.8    15.0      M    M
 26000  -33.7 -28.7   245   64   33   7.2   4.0   31.3  88.4    14.6      M    M
 25000  -31.7 -25.1   245   61   31   6.7   3.7   30.3  86.6    13.9      M    M
 24000  -29.3 -20.7   245   58   30   8.5   4.7   29.5  85.2    13.5      M    M
 23000  -26.7 -16.1   245   54   28   9.4   5.1   29.2  84.5    13.3      M    M
 22000  -23.8 -10.8   240   51   26   9.3   5.1   29.0  84.3    13.4      M    M
 21000  -21.8  -7.2   240   47   24   2.2   1.2   28.0  82.4    12.7      M    M
 20000  -20.5  -4.9   240   49   25   9.5   5.2   26.1  79.1    11.2      M    M
 19500  -18.5  -1.3   240   47   24   8.7   4.8   25.9  78.6    11.1      M    M
 19000  -17.4   0.7   235   45   23   4.9   2.7   25.5  77.9    10.9      M    M
 18500  -16.6   2.1   235   44   23   6.8   3.7   24.7  76.4    10.3      M    M
 18000  -15.5   4.1   235   45   23   7.1   3.9   24.2  75.6     9.9      M    M
 17500  -14.6   5.7   235   47   24   6.9   3.8   23.7  74.6     9.4      M    M
 17000  -13.5   7.7   230   48   25   8.1   4.5   23.4  74.1     9.1      M    M
 16500  -12.3   9.9   230   49   25   7.8   4.3   23.1  73.5     8.9      M    M
 16000  -11.1  12.0   230   50   26   7.1   3.9   22.7  72.9     8.7      M    M
 15500  -10.4  13.3   230   47   24   7.4   4.1   22.0  71.6     8.0      M    M
 15000   -8.9  16.0   230   44   22   7.4   4.1   21.9  71.5     8.0      M    M
 14500   -7.9  17.8   225   41   21   4.9   2.7   21.5  70.7     7.6      M    M
 14000   -7.6  18.3   225   38   20   3.9   2.1   20.4  68.8     6.5      M    M
 13500   -6.7  19.9   230   38   19   9.0   4.9   19.8  67.7     5.9      M    M
 13000   -5.5  22.1   230   37   19   8.5   4.7   19.6  67.3     5.7      M    M
 12500   -4.2  24.4   235   37   19   8.5   4.7   19.4  67.0     5.5      M    M
 12000   -3.0  26.6   235   37   19   8.3   4.5   19.2  66.6     5.3      M    M
 11500   -1.8  28.8   235   32   16   8.8   4.8   19.0  66.1     5.1      M    M
 11000   -0.8  30.6   230   27   14   3.6   2.0   18.4  65.1     4.6      M    M
 10500   -0.2  31.6   225   22   11   4.1   2.3   17.5  63.4     3.8      M    M
 10250    0.0  32.0   225   20   10   3.6   2.0   17.0  62.6     3.3      M    M
 10000    0.3  32.5   220   17    9   5.7   3.1   16.6  61.8     2.9      M    M
  9750    0.9  33.6   220   16    8   8.3   4.6   16.4  61.5     2.8      M    M
  9500    1.5  34.7   215   14    7   8.2   4.5   16.3  61.3     2.6      M    M
  9250    2.1  35.8   215   13    7   8.2   4.5   16.2  61.1     2.5      M    M
  9000    2.7  36.9   210   11    6   8.2   4.5   16.1  60.9     2.4      M    M
  8750    3.3  37.9   205   11    6   8.2   4.5   15.9  60.7     2.3      M    M
  8500    3.9  39.0   200   12    6   8.2   4.5   15.8  60.4     2.2      M    M
  8250    4.6  40.3   195   12    6   8.1   4.4   15.7  60.2     2.1      M    M
  8000    5.2  41.4   190   13    7   8.6   4.7   15.6  60.0     2.0      M    M
  7750    5.8  42.4   185   12    6   6.7   3.7   15.4  59.8     1.8      M    M
  7500    6.1  43.0   175   11    6   1.8   1.0   15.0  59.0     1.4      M    M
  7250    5.8  42.4   165   11    6 -13.4  -7.3   14.0  57.1     0.4      M    M
  7000    4.6  40.3   155   11    6  -8.7  -4.8   12.0  53.5    -1.5    169  0.9
  6750    4.7  40.5   150    9    5   4.4   2.4   11.3  52.4    -2.1    159  0.8
  6500    4.8  40.6   145    7    4   1.2   0.6   10.7  51.3    -2.8    148  0.8
  6250    5.0  41.0   140    5    2   2.1   1.1   10.1  50.2    -3.4    137  0.7
  6000    5.2  41.4   120    3    1   2.1   1.1    9.5  49.2    -3.9    123  0.6
  5750    5.4  41.7   110    2    1   2.3   1.3    9.0  48.1    -4.4    107  0.5
  5500    5.7  42.3   110    2    1   4.2   2.3    8.4  47.2    -4.8     92  0.5
  5250    6.0  42.8   105    3    1   0.9   0.5    8.0  46.4    -5.3     77  0.4
  5000    5.3  41.5   105    3    1 -21.1 -11.6    6.6  44.0    -6.7     90  0.5

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

           11/23/2020 at 0800 MST          |       11/23/2020 at 1100 MST
                                           |
CAPE...     0.0    LI...       +0.9        | CAPE...    +9.9    LI...       +1.0
CINH...    -0.2    K Index... +15.1        | CINH...    -7.1    K Index... +14.0
                                           |
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 -60.4 -76.7  250  30 16   0.2   0.1 | -59.4 -74.9  245  30 16   0.8   0.5
 45000 -60.0 -76.0  250  37 19   0.2   0.1 | -58.1 -72.6  245  35 18   0.9   0.5
 40000 -59.2 -74.6  240  54 28   0.5   0.3 | -58.8 -73.8  240  54 28  -0.5  -0.3
 38000 -57.7 -71.9  240  57 29   5.4   2.9 | -57.9 -72.2  240  59 30   4.8   2.7
 36000 -54.1 -65.4  240  56 29   5.3   2.9 | -54.7 -66.5  235  57 29   4.8   2.6
 34000 -50.9 -59.6  240  54 28   5.0   2.7 | -51.8 -61.2  235  55 28   5.6   3.1
 32000 -47.9 -54.2  240  48 24   5.0   2.8 | -48.5 -55.3  235  49 25   5.5   3.0
 30000 -44.6 -48.3  240  42 22   8.1   4.5 | -44.9 -48.8  235  42 22   8.3   4.6
 29000 -42.2 -44.0  240  40 20   8.0   4.4 | -42.5 -44.5  235  40 21   8.1   4.4
 28000 -39.8 -39.6  240  37 19   8.0   4.4 | -40.1 -40.2  235  38 20   8.1   4.4
 27000 -37.5 -35.5  240  35 18   8.0   4.4 | -37.7 -35.9  235  36 19   8.1   4.4
 26000 -35.0 -31.0  240  33 17   8.2   4.5 | -35.3 -31.5  235  35 18   8.0   4.4
 25000 -32.5 -26.5  240  31 16   8.2   4.5 | -32.9 -27.2  235  33 17   8.0   4.4
 24000 -30.1 -22.2  240  29 15   8.3   4.5 | -30.5 -22.9  230  31 16   8.0   4.4
 23000 -27.7 -17.9  240  28 14   7.9   4.4 | -28.1 -18.6  230  30 15   7.8   4.3
 22000 -24.7 -12.5  240  26 13   8.0   4.4 | -25.2 -13.4  230  28 14   7.8   4.3
 21000 -22.4  -8.3  235  25 13   6.8   3.7 | -22.9  -9.2  230  27 14   7.2   4.0
 20000 -20.4  -4.7  235  24 12   6.6   3.6 | -20.8  -5.4  230  25 13   7.0   3.8
 19500 -19.4  -2.9  235  23 12   6.6   3.6 | -19.8  -3.6  230  24 12   7.0   3.8
 19000 -18.5  -1.3  235  23 12   6.6   3.6 | -18.7  -1.7  230  23 12   7.0   3.8
 18500 -17.5   0.5  235  22 11   6.7   3.7 | -17.7   0.1  230  22 11   6.6   3.6
 18000 -16.5   2.3  235  22 11   6.7   3.7 | -16.8   1.8  230  21 11   6.1   3.4
 17500 -15.5   4.1  235  21 11   6.8   3.7 | -15.9   3.4  230  20 11   6.1   3.3
 17000 -14.5   5.9  235  21 11   7.1   3.9 | -15.0   5.0  230  20 10   6.4   3.5
 16500 -13.4   7.9  235  21 11   7.2   3.9 | -14.0   6.8  230  19 10   6.4   3.5
 16000 -12.4   9.7  235  20 10   6.6   3.6 | -13.1   8.4  230  18  9   6.1   3.4
 15500 -11.4  11.5  235  19 10   6.6   3.6 | -12.2  10.0  230  17  9   6.1   3.3
 15000 -10.5  13.1  235  19 10   6.7   3.7 | -11.3  11.7  230  17  9   6.2   3.4
 14500  -9.5  14.9  235  18  9   6.8   3.7 | -10.4  13.3  230  16  8   6.5   3.5
 14000  -8.5  16.7  235  17  9   6.8   3.7 |  -9.5  14.9  230  15  8   6.6   3.6
 13500  -7.6  18.3  235  17  9   6.7   3.7 |  -8.5  16.7  230  14  7   7.1   3.9
 13000  -6.6  20.1  230  16  8   6.8   3.7 |  -7.5  18.5  225  14  7   7.1   3.9
 12500  -5.6  21.9  230  15  8   7.6   4.2 |  -6.4  20.5  225  13  7   8.0   4.4
 12000  -4.5  23.9  230  14  7   7.6   4.2 |  -5.3  22.5  225  13  7   8.0   4.4
 11500  -3.5  25.7  225  14  7   7.5   4.1 |  -4.2  24.4  220  12  6   7.8   4.3
 11000  -2.4  27.7  225  13  7   7.5   4.1 |  -3.0  26.6  220  12  6   7.8   4.3
 10500  -1.5  29.3  225  12  6   5.3   2.9 |  -2.0  28.4  220  11  6   6.0   3.3
 10250  -1.1  30.0  220  12  6   6.0   3.3 |  -1.6  29.1  220  11  6   7.0   3.8
 10000  -0.5  31.1  220  11  6   9.3   5.1 |  -1.0  30.2  215  10  5  10.8   5.9
  9750   0.2  32.4  215  11  6   8.3   4.6 |  -0.1  31.8  215  10  5   9.4   5.1
  9500   0.6  33.1  215  11  6   5.8   3.2 |   0.4  32.7  215  10  5   6.5   3.6
  9250   1.1  34.0  215  11  5   6.3   3.4 |   0.9  33.6  215   9  5   6.8   3.7
  9000   1.5  34.7  215  10  5   7.0   3.8 |   1.4  34.5  215   9  5   8.6   4.7
  8750   2.1  35.8  210  10  5   6.9   3.8 |   2.1  35.8  215   9  5   9.1   5.0
  8500   2.5  36.5  210  10  5   5.8   3.2 |   2.7  36.9  215   9  4   7.1   3.9
  8250   3.0  37.4  210   9  5   6.2   3.4 |   3.2  37.8  215   8  4   8.3   4.6
  8000   3.4  38.1  205   9  4   5.7   3.1 |   3.8  38.8  215   8  4   5.4   2.9
  7750   4.2  39.6  200   7  4   5.2   2.8 |   4.6  40.3  215   6  3   8.0   4.4
  7500   4.6  40.3  200   6  3   5.2   2.9 |   5.2  41.4  215   5  3   6.9   3.8
  7250   5.0  41.0  195   6  3   5.6   3.1 |   5.6  42.1  215   4  2   3.4   1.9
  7000   5.4  41.7  195   5  3   4.9   2.7 |   5.8  42.4  220   3  2   6.4   3.5
  6750   5.7  42.3  190   4  2   4.6   2.5 |   6.6  43.9  220   3  1  11.4   6.2
  6500   6.1  43.0  185   3  2   3.5   1.9 |   7.4  45.3  225   3  1   9.2   5.0
  6250   6.2  43.2  180   2  1   0.9   0.5 |   8.0  46.4  235   2  1   8.5   4.6
  6000   6.4  43.5  175   1  1   4.2   2.3 |   8.6  47.5  255   2  1   8.4   4.6
  5750   6.6  43.9  150   1  0  -4.6  -2.5 |   9.4  48.9  240   2  1  12.8   7.0
  5500   3.8  38.8  035   1  0 -92.2 -50.6 |  11.0  51.8  270   1  1  37.4  20.5
  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

           11/23/2020 at 1400 MST          |       11/23/2020 at 1700 MST
                                           |
CAPE...   +26.2    LI...       +0.2        | CAPE...    +1.7    LI...       -0.0
CINH...   -26.6    K Index... +17.2        | CINH...   -10.8    K Index... +20.9
                                           |
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 -59.0 -74.2  250  30 15   1.0   0.6 | -58.6 -73.5  250  27 14   1.8   1.0
 45000 -57.4 -71.3  245  36 19   1.2   0.7 | -55.7 -68.3  245  33 17   2.1   1.1
 40000 -57.9 -72.2  235  51 26  -0.4  -0.2 | -55.8 -68.4  235  43 22  -0.2  -0.1
 38000 -57.2 -71.0  235  55 28   4.0   2.2 | -55.5 -67.9  235  47 24   1.9   1.0
 36000 -54.8 -66.6  235  56 29   4.0   2.2 | -54.3 -65.7  230  49 25   1.9   1.1
 34000 -52.0 -61.6  235  56 29   5.5   3.0 | -52.9 -63.2  230  51 26   4.4   2.4
 32000 -48.7 -55.7  235  50 26   5.5   3.0 | -49.8 -57.6  230  46 24   5.2   2.8
 30000 -45.3 -49.5  235  44 23   8.1   4.4 | -46.6 -51.9  230  41 21   7.7   4.3
 29000 -42.9 -45.2  230  42 22   7.8   4.3 | -44.2 -47.6  230  40 21   8.1   4.4
 28000 -40.6 -41.1  230  41 21   7.8   4.3 | -41.8 -43.2  230  38 20   8.1   4.4
 27000 -38.3 -36.9  230  39 20   7.8   4.3 | -39.4 -38.9  230  37 19   8.1   4.4
 26000 -35.9 -32.6  230  37 19   7.8   4.3 | -37.1 -34.8  230  35 18   7.6   4.2
 25000 -33.6 -28.5  230  35 18   7.8   4.3 | -34.8 -30.6  230  34 17   7.6   4.2
 24000 -31.3 -24.3  230  33 17   7.8   4.3 | -32.6 -26.7  230  32 17   7.6   4.2
 23000 -28.9 -20.0  230  32 16   7.7   4.2 | -30.3 -22.5  230  31 16   7.4   4.1
 22000 -26.6 -15.9  230  30 15   7.7   4.2 | -28.1 -18.6  235  29 15   7.4   4.1
 21000 -23.8 -10.8  230  28 14   7.3   4.0 | -25.4 -13.7  235  26 13   7.2   4.0
 20000 -21.7  -7.1  230  26 13   7.1   3.9 | -23.3  -9.9  235  23 12   7.0   3.8
 19500 -20.6  -5.1  230  25 13   7.1   3.9 | -22.3  -8.1  235  22 11   7.0   3.8
 19000 -19.6  -3.3  230  24 12   7.1   3.9 | -21.2  -6.2  230  21 11   7.0   3.8
 18500 -18.5  -1.3  230  23 12   6.9   3.8 | -20.2  -4.4  230  19 10   7.0   3.9
 18000 -17.5   0.5  230  22 11   6.5   3.6 | -19.2  -2.6  230  18  9   7.1   3.9
 17500 -16.6   2.1  230  21 11   6.6   3.6 | -18.1  -0.6  230  17  9   7.1   3.9
 17000 -15.6   3.9  230  20 10   6.0   3.3 | -17.0   1.4  230  16  8   7.6   4.2
 16500 -14.7   5.5  230  19 10   6.1   3.3 | -15.9   3.4  230  15  8   7.6   4.2
 16000 -13.8   7.2  230  18  9   6.3   3.4 | -14.8   5.4  230  14  7   7.7   4.2
 15500 -12.9   8.8  230  17  9   6.4   3.5 | -13.7   7.3  225  14  7   7.7   4.2
 15000 -12.0  10.4  225  16  8   6.5   3.6 | -12.5   9.5  225  14  7   7.7   4.2
 14500 -11.0  12.2  225  15  8   6.9   3.8 | -11.4  11.5  225  13  7   7.8   4.3
 14000 -10.0  14.0  225  15  8   6.9   3.8 | -10.3  13.5  225  13  7   7.9   4.3
 13500  -8.9  16.0  220  14  7   8.4   4.6 |  -9.1  15.6  225  12  6   8.1   4.4
 13000  -7.7  18.1  220  13  7   8.3   4.5 |  -7.9  17.8  225  12  6   8.1   4.4
 12500  -6.5  20.3  220  13  7   8.9   4.9 |  -6.7  19.9  225  12  6   7.9   4.3
 12000  -5.2  22.6  220  13  7   8.8   4.8 |  -5.6  21.9  225  11  6   7.9   4.3
 11500  -4.0  24.8  220  13  6   8.8   4.8 |  -4.4  24.1  225  11  6   8.0   4.4
 11000  -2.7  27.1  215  12  6   9.1   5.0 |  -3.3  26.1  225  10  5   8.1   4.5
 10500  -1.6  29.1  215  11  6   5.9   3.2 |  -2.2  28.0  225  10  5   6.6   3.6
 10250  -1.1  30.0  215  10  5   7.1   3.9 |  -1.7  28.9  225  10  5   7.1   3.9
 10000  -0.5  31.1  215  10  5  10.6   5.8 |  -1.1  30.0  225  10  5   9.8   5.4
  9750   0.3  32.5  215  10  5   9.2   5.1 |  -0.3  31.5  230   9  5   8.9   4.9
  9500   0.8  33.4  220   9  5   6.8   3.7 |   0.2  32.4  230   9  4   6.6   3.6
  9250   1.3  34.3  220   8  4   6.6   3.6 |   0.7  33.3  230   8  4   6.9   3.8
  9000   1.9  35.4  220   8  4   9.6   5.3 |   1.2  34.2  235   8  4   8.0   4.4
  8750   2.7  36.9  220   8  4   9.9   5.4 |   1.8  35.2  240   7  4   8.2   4.5
  8500   3.2  37.8  220   7  4   6.7   3.7 |   2.4  36.3  240   7  4   7.1   3.9
  8250   3.8  38.8  225   7  3   8.0   4.4 |   2.9  37.2  245   6  3   7.4   4.1
  8000   4.3  39.7  230   6  3   5.8   3.2 |   3.5  38.3  250   6  3   7.5   4.1
  7750   4.7  40.5  240   5  2   6.8   3.7 |   4.5  40.1  260   5  3   6.7   3.7
  7500   5.4  41.7  240   5  2   9.3   5.1 |   5.0  41.0  265   5  3   7.2   3.9
  7250   6.7  44.1  250   4  2   7.1   3.9 |   5.5  41.9  275   4  2   5.7   3.1
  7000   7.2  45.0  265   4  2   8.2   4.5 |   5.9  42.6  280   5  3   5.6   3.1
  6750   8.0  46.4  265   4  2  11.4   6.2 |   6.4  43.5  285   4  2   6.9   3.8
  6500   8.7  47.7  260   4  2  10.2   5.6 |   6.8  44.2  295   4  2   6.9   3.8
  6250   9.5  49.1  265   4  2  10.1   5.5 |   7.4  45.3  300   4  2   8.0   4.4
  6000  10.2  50.4  280   4  2   8.4   4.6 |   8.0  46.4  305   4  2   7.7   4.2
  5750  10.8  51.4  275   4  2  11.2   6.2 |   8.4  47.1  305   3  2   3.5   1.9
  5500  12.6  54.7  285   3  2  45.8  25.1 |   8.4  47.1  320   2  1  -6.5  -3.5
  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.

CINH (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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