Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 271251
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0551 MST Monday, February 27, 2017

This forecast is for Monday, February 27, 2017:

If the trigger temperature of 47.1 F/8.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8795 ft MSL (3956 ft AGL)

Forecast maximum temperature................... 47.0 F/8.8 C
Time of trigger temperature.................... 1330 MST
Time of overdevelopment........................ None
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................. 5183 ft MSL (344 ft AGL)
Thermal soaring outlook for Tuesday 02/28...... Fair

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

Remarks...

Sunrise/Sunset.................... 06:48:58 / 18:03:48 MST
Total possible sunshine........... 11 hr 14 min 50 sec (674 min 50 sec)
Altitude of sun at 12:26:38 MST... 42.86 degrees

Upper air data from rawinsonde observation taken on 02/27/2017 at 0500 MST

Freezing level.................. 7225 ft MSL (2386 ft AGL)
Convective condensation level... 12865 ft MSL (8026 ft AGL)
Lifted condensation level....... 12630 ft MSL (7790 ft AGL)
Lifted index.................... +5.4
K index......................... +12.8

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  -56.4 -69.5   255   57   29   3.6   2.0  111.8 233.2    58.3      M    M
 45000  -54.4 -65.9   255   71   37  -1.3  -0.7   90.0 193.9    49.2      M    M
 40000  -56.7 -70.1   260   60   31  -2.3  -1.2   62.7 144.9    35.0      M    M
 38000  -54.9 -66.8   270   72   37   1.5   0.8   55.3 131.5    31.2      M    M
 36000  -58.4 -73.1   255   65   33  -3.5  -1.9   41.5 106.6    22.6      M    M
 34000  -58.3 -72.9   265   65   33  -0.5  -0.3   33.0  91.4    17.3      M    M
 32000  -55.0 -67.0   270   68   35   6.2   3.4   29.6  85.2    15.3      M    M
 30000  -52.5 -62.5   260   72   37   5.7   3.1   24.9  76.9    12.3      M    M
 29000  -50.5 -58.9   255   74   38   8.4   4.6   23.6  74.5    11.5      M    M
 28000  -48.1 -54.6   255   73   37   8.2   4.5   22.9  73.3    11.1      M    M
 27000  -45.6 -50.1   255   72   37   8.2   4.5   22.4  72.3    10.8      M    M
 26000  -43.1 -45.6   255   70   36   8.4   4.6   21.8  71.3    10.5      M    M
 25000  -40.6 -41.1   255   69   36   8.4   4.6   21.4  70.5    10.3      M    M
 24000  -38.1 -36.6   255   67   34   8.3   4.6   20.8  69.5    10.0      M    M
 23000  -35.8 -32.4   255   65   33   7.5   4.1   19.9  67.9     9.4      M    M
 22000  -33.4 -28.1   255   63   33   8.0   4.4   19.2  66.5     8.9      M    M
 21000  -31.1 -24.0   250   62   32   7.9   4.4   18.6  65.4     8.5      M    M
 20000  -28.5 -19.3   250   59   31   5.3   2.9   17.3  63.2     7.5      M    M
 19500  -27.9 -18.2   250   57   29   3.7   2.0   16.3  61.4     6.7      M    M
 19000  -27.0 -16.6   250   54   28   7.5   4.1   15.7  60.2     6.2      M    M
 18500  -26.0 -14.8   250   51   26   7.0   3.8   15.2  59.4     5.8      M    M
 18000  -24.9 -12.8   250   49   25   6.8   3.7   14.7  58.5     5.4      M    M
 17500  -23.9 -11.0   250   46   24   5.7   3.2   14.2  57.6     5.0      M    M
 17000  -23.2  -9.8   245   43   22   3.6   2.0   13.3  56.0     4.3      M    M
 16500  -23.0  -9.4   245   40   21   0.5   0.3   11.9  53.5     3.1      M    M
 16000  -22.4  -8.3   240   38   20   7.8   4.3   10.9  51.7     2.2      M    M
 15500  -21.3  -6.3   240   38   20   7.8   4.3   10.6  51.0     1.8      M    M
 15000  -20.1  -4.2   240   39   20   7.8   4.3   10.2  50.4     1.5      M    M
 14500  -19.0  -2.2   240   39   20   7.8   4.3    9.9  49.9     1.2      M    M
 14000  -17.8  -0.0   240   39   20   7.8   4.3    9.6  49.3     1.0      M    M
 13500  -16.6   2.1   240   39   20   8.7   4.7    9.3  48.8     0.7      M    M
 13000  -15.2   4.6   235   39   20   9.3   5.1    9.2  48.6     0.6      M    M
 12500  -13.8   7.2   235   40   20   9.4   5.1    9.2  48.6     0.6      M    M
 12000  -12.4   9.7   235   40   21   9.4   5.1    9.2  48.5     0.5      M    M
 11500  -11.0  12.2   235   38   19   9.4   5.1    9.1  48.3     0.4      M    M
 11000   -9.6  14.7   235   36   18   9.4   5.1    9.0  48.1     0.3      M    M
 10500   -8.2  17.2   230   34   17   9.4   5.1    8.9  48.0     0.3      M    M
 10250   -7.5  18.5   230   32   17   9.4   5.1    8.9  48.0     0.3      M    M
 10000   -6.8  19.8   230   31   16   9.3   5.1    8.8  47.9     0.2      M    M
  9750   -6.1  21.0   230   30   16   9.4   5.2    8.8  47.9     0.2      M    M
  9500   -5.4  22.3   230   30   15   9.5   5.2    8.8  47.9     0.2      M    M
  9250   -4.7  23.5   225   29   15   9.5   5.2    8.8  47.8     0.2      M    M
  9000   -4.0  24.8   225   29   15   9.5   5.2    8.8  47.8     0.2      M    M
  8750   -3.4  25.9   220   28   14   4.4   2.4    8.6  47.5    -0.0    260  1.3
  8500   -3.2  26.2   215   26   13   6.8   3.7    8.1  46.7    -0.5    245  1.2
  8250   -2.5  27.5   210   25   13   6.5   3.6    8.1  46.6    -0.6    217  1.1
  8000   -2.2  28.0   200   24   12   7.8   4.3    7.7  45.8    -1.0    200  1.0
  7750   -1.3  29.7   200   23   12  10.9   6.0    7.8  46.1    -0.8    166  0.8
  7500   -0.7  30.7   200   23   12   6.6   3.6    7.7  45.8    -1.0    142  0.7
  7250   -0.2  31.6   200   22   11   7.8   4.3    7.5  45.5    -1.1    118  0.6
  7000    0.4  32.7   200   21   11   7.4   4.1    7.3  45.2    -1.3     94  0.5
  6750    0.9  33.6   200   21   11   7.5   4.1    7.2  44.9    -1.5     69  0.4
  6500    1.5  34.7   195   21   11   7.5   4.1    7.0  44.6    -1.7     45  0.2
  6250    2.1  35.8   195   22   11   7.5   4.1    6.8  44.3    -1.8     21  0.1
  6000    2.6  36.7   190   22   11   7.6   4.2    6.7  44.0    -2.0      M    M
  5750    3.2  37.8   185   19   10   7.3   4.0    6.5  43.7    -2.2      M    M
  5500    3.7  38.7   180   16    8   8.2   4.5    6.3  43.4    -2.4      M    M
  5250    4.3  39.7   175   13    7   4.9   2.7    6.1  43.1    -2.6      M    M
  5000    4.3  39.7   160   10    5  -3.8  -2.1    5.4  41.8    -3.3      M    M

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

           02/27/2017 at 0800 MST          |       02/27/2017 at 1100 MST
                                           |
K index... +10.7  LI... +3.5               | K index... +15.9  LI... +2.6
CAPE... +19.5  CIN... -2.3                 | CAPE... +41.3  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 -56.2 -69.2  255  38 20   0.6   0.3 | -55.4 -67.7  255  36 18   0.7   0.4
 45000 -55.3 -67.5  260  60 31   0.6   0.3 | -54.3 -65.7  260  58 30   0.7   0.4
 40000 -56.5 -69.7  265  73 38  -1.2  -0.6 | -56.3 -69.3  260  79 40  -1.8  -1.0
 38000 -57.2 -71.0  265  77 40  -0.7  -0.4 | -57.4 -71.3  265  86 44  -1.1  -0.6
 36000 -57.3 -71.1  265  78 40  -0.2  -0.1 | -57.6 -71.7  260  95 49  -0.3  -0.2
 34000 -57.4 -71.3  260  78 40  -0.2  -0.1 | -57.8 -72.0  260 104 54  -0.3  -0.2
 32000 -55.4 -67.7  260  82 42   5.2   2.8 | -55.6 -68.1  260 107 55   6.0   3.3
 30000 -52.3 -62.1  260  87 45   5.2   2.9 | -52.0 -61.6  260 106 55   6.0   3.3
 29000 -50.5 -58.9  260  87 45   7.6   4.2 | -50.0 -58.0  260 104 54   7.5   4.1
 28000 -48.2 -54.8  260  83 43   7.6   4.1 | -47.7 -53.9  260  98 51   7.5   4.1
 27000 -46.0 -50.8  260  79 41   7.6   4.1 | -44.9 -48.8  255  92 47   7.5   4.1
 26000 -43.1 -45.6  260  75 39   8.0   4.4 | -42.7 -44.9  255  87 45   8.0   4.4
 25000 -40.7 -41.3  255  74 38   7.9   4.3 | -40.3 -40.5  255  83 43   8.0   4.4
 24000 -38.4 -37.1  255  73 37   7.9   4.3 | -37.9 -36.2  255  80 41   8.0   4.4
 23000 -36.0 -32.8  255  71 36   7.6   4.2 | -35.5 -31.9  255  76 39   7.8   4.3
 22000 -33.7 -28.7  255  68 35   7.6   4.2 | -33.2 -27.8  255  72 37   7.8   4.3
 21000 -31.5 -24.7  255  64 33   7.7   4.2 | -30.8 -23.4  255  68 35   7.8   4.3
 20000 -29.1 -20.4  255  60 31   8.4   4.6 | -28.5 -19.3  250  62 32   7.8   4.3
 19500 -27.8 -18.0  250  57 29   8.4   4.6 | -27.3 -17.1  250  58 30   7.8   4.3
 19000 -26.6 -15.9  250  54 28   8.4   4.6 | -26.2 -15.2  245  55 28   7.8   4.3
 18500 -25.3 -13.5  250  51 26   8.4   4.6 | -25.0 -13.0  245  51 26   7.8   4.3
 18000 -24.0 -11.2  250  48 25   8.3   4.6 | -23.8 -10.8  240  48 25   7.6   4.2
 17500 -22.8  -9.0  250  47 24   8.1   4.5 | -22.8  -9.0  240  46 24   7.1   3.9
 17000 -21.6  -6.9  245  46 24   8.3   4.5 | -21.7  -7.1  240  45 23   7.4   4.1
 16500 -20.5  -4.9  245  46 24   6.8   3.8 | -20.8  -5.4  240  45 23   4.7   2.6
 16000 -19.4  -2.9  245  47 24   7.0   3.8 | -20.1  -4.2  240  46 24   4.9   2.7
 15500 -18.5  -1.3  245  47 24   4.8   2.6 | -19.4  -2.9  240  47 24   4.4   2.4
 15000 -17.9  -0.2  240  46 24   4.0   2.2 | -18.8  -1.8  240  45 23   4.3   2.4
 14500 -17.4   0.7  240  45 23   3.4   1.9 | -18.2  -0.8  240  43 22   4.8   2.7
 14000 -17.0   1.4  240  46 23   2.8   1.5 | -17.4   0.7  240  42 22   5.6   3.1
 13500 -16.6   2.1  240  46 24   3.4   1.9 | -16.6   2.1  240  41 21   6.1   3.4
 13000 -15.5   4.1  235  43 22   5.2   2.8 | -15.0   5.0  240  40 21   7.8   4.3
 12500 -14.7   5.5  235  41 21   7.2   3.9 | -13.8   7.2  240  40 20   7.5   4.1
 12000 -13.6   7.5  235  40 21   7.6   4.2 | -12.7   9.1  235  39 20   7.5   4.1
 11500 -12.4   9.7  235  40 20   7.9   4.3 | -11.6  11.1  235  38 19   7.5   4.1
 11000 -11.3  11.7  235  38 20   8.0   4.4 | -10.5  13.1  235  36 19   7.6   4.1
 10500 -10.1  13.8  240  37 19   7.5   4.1 |  -9.4  15.1  235  35 18   7.4   4.0
 10250  -9.6  14.7  240  36 19   7.4   4.0 |  -8.9  16.0  235  34 17   7.4   4.0
 10000  -9.1  15.6  240  35 18   8.1   4.5 |  -8.3  17.1  230  33 17   8.1   4.4
  9750  -8.4  16.9  240  34 17   8.7   4.8 |  -7.7  18.1  230  32 17   8.2   4.5
  9500  -7.8  18.0  235  32 16   8.3   4.6 |  -7.2  19.0  225  31 16   7.7   4.2
  9250  -7.2  19.0  235  30 15   9.0   4.9 |  -6.6  20.1  225  30 15   8.2   4.5
  9000  -6.6  20.1  235  28 14   6.6   3.6 |  -6.0  21.2  220  28 15   6.7   3.7
  8750  -6.2  20.8  235  27 14   5.9   3.2 |  -5.6  21.9  220  27 14   6.7   3.7
  8500  -5.6  21.9  230  25 13   7.8   4.3 |  -5.0  23.0  220  25 13   8.4   4.6
  8250  -5.1  22.8  230  23 12   7.3   4.0 |  -4.4  24.1  215  23 12   7.6   4.1
  8000  -4.6  23.7  225  22 11   7.5   4.1 |  -3.8  25.2  215  21 11   9.2   5.1
  7750  -4.0  24.8  225  19 10   6.1   3.4 |  -3.1  26.4  215  20 10   9.5   5.2
  7500  -3.7  25.3  220  17  9   5.1   2.8 |  -2.5  27.5  215  19 10   8.2   4.5
  7250  -3.3  26.1  220  16  8   5.4   3.0 |  -1.9  28.6  215  18  9   8.5   4.7
  7000  -2.9  26.8  215  14  7   5.0   2.8 |  -1.2  29.8  215  17  9   9.1   5.0
  6750  -2.5  27.5  205  13  6   4.3   2.4 |  -0.5  31.1  215  16  8   9.9   5.4
  6500  -2.2  28.0  195  11  6   4.2   2.3 |   0.2  32.4  215  15  8   9.7   5.3
  6250  -1.9  28.6  185  10  5   3.7   2.0 |   0.9  33.6  215  14  7  10.2   5.6
  6000  -1.7  28.9  180   9  5   3.0   1.7 |   1.7  35.1  215  14  7  10.8   5.9
  5750  -1.4  29.5  170   8  4   3.3   1.8 |   2.5  36.5  215  13  6  10.3   5.7
  5500  -1.2  29.8  165   7  3   3.3   1.8 |   3.3  37.9  220  11  6  10.0   5.5
  5250  -1.0  30.2  165   6  3   3.0   1.6 |   4.0  39.2  220  11  5  10.0   5.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/27/2017 at 1400 MST          |       02/27/2017 at 1700 MST
                                           |
K index... +15.6  LI... +1.7               | K index... +9.3  LI... +1.5
CAPE... +80.8  CIN... -0.3                 | CAPE... +58.7  CIN... -6.5
                                           |
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 -55.6 -68.1  255  44 23   0.4   0.2 | -55.8 -68.4  255  55 28   0.5   0.3
 45000 -55.0 -67.0  260  65 34   0.4   0.2 | -55.0 -67.0  255  71 36   0.5   0.3
 40000 -57.5 -71.5  260  88 46  -2.1  -1.2 | -57.4 -71.3  260  92 47  -2.0  -1.1
 38000 -58.7 -73.7  260  98 50   0.2   0.1 | -58.5 -73.3  260 101 52  -0.0  -0.0
 36000 -58.0 -72.4  260 114 59   1.2   0.7 | -58.1 -72.6  260 119 61   0.8   0.4
 34000 -57.2 -71.0  260 131 67   1.4   0.7 | -57.6 -71.7  260 137 71   0.9   0.5
 32000 -54.2 -65.6  260 132 68   6.6   3.6 | -54.0 -65.2  260 145 75   8.0   4.4
 30000 -50.2 -58.4  260 127 65   6.6   3.6 | -49.2 -56.6  260 149 77   8.0   4.4
 29000 -48.2 -54.8  260 121 62   7.1   3.9 | -47.0 -52.6  260 145 75   6.8   3.7
 28000 -46.1 -51.0  260 114 59   7.1   3.9 | -45.0 -49.0  260 137 70   6.7   3.7
 27000 -44.0 -47.2  260 106 55   7.1   3.9 | -42.9 -45.2  260 128 66   6.7   3.7
 26000 -41.8 -43.2  260  99 51   6.7   3.7 | -40.9 -41.6  260 118 61   6.6   3.6
 25000 -39.9 -39.8  255  93 48   6.5   3.6 | -39.0 -38.2  255 101 52   6.5   3.6
 24000 -37.9 -36.2  255  87 45   6.5   3.6 | -37.0 -34.6  255  84 43   6.5   3.6
 23000 -36.0 -32.8  255  82 42   7.4   4.1 | -35.1 -31.2  250  68 35   6.5   3.6
 22000 -33.0 -27.4  255  76 39   7.9   4.3 | -32.6 -26.7  255  71 37   6.6   3.6
 21000 -30.6 -23.1  255  72 37   7.9   4.3 | -30.7 -23.3  255  74 38   6.6   3.6
 20000 -28.2 -18.8  250  67 34   7.8   4.3 | -28.5 -19.3  255  74 38   7.7   4.2
 19500 -27.1 -16.8  250  64 33   7.8   4.3 | -27.3 -17.1  255  73 38   7.8   4.3
 19000 -25.9 -14.6  250  62 32   7.8   4.3 | -26.2 -15.2  255  72 37   7.8   4.3
 18500 -24.7 -12.5  250  59 30   7.8   4.3 | -25.0 -13.0  255  71 37   7.7   4.2
 18000 -23.5 -10.3  245  56 29   7.0   3.8 | -23.8 -10.8  255  70 36   6.7   3.7
 17500 -22.6  -8.7  245  55 28   6.4   3.5 | -23.0  -9.4  255  68 35   5.7   3.1
 17000 -21.7  -7.1  245  53 27   6.2   3.4 | -22.1  -7.8  255  65 34   5.6   3.1
 16500 -20.9  -5.6  245  52 27   4.3   2.4 | -21.4  -6.5  255  63 32   4.6   2.5
 16000 -20.3  -4.5  245  51 26   4.6   2.5 | -20.7  -5.3  255  60 31   4.6   2.5
 15500 -19.7  -3.5  245  50 26   4.3   2.4 | -20.0  -4.0  255  57 29   5.1   2.8
 15000 -19.0  -2.2  245  48 25   4.2   2.3 | -19.2  -2.6  255  53 27   5.1   2.8
 14500 -18.3  -0.9  245  46 24   6.7   3.7 | -18.4  -1.1  255  50 26   7.0   3.8
 14000 -17.2   1.0  240  45 23   7.5   4.1 | -17.3   0.9  250  49 25   7.8   4.3
 13500 -16.1   3.0  240  45 23   7.4   4.1 | -16.1   3.0  250  47 24   8.3   4.5
 13000 -15.0   5.0  240  45 23   7.3   4.0 | -14.9   5.2  245  47 24   8.7   4.7
 12500 -13.9   7.0  240  46 24   7.5   4.1 | -13.6   7.5  245  48 25   8.9   4.9
 12000 -12.8   9.0  240  45 23   7.8   4.3 | -12.2  10.0  240  47 24   9.2   5.0
 11500 -11.6  11.1  235  44 22   7.9   4.3 | -10.9  12.4  240  46 24   9.2   5.1
 11000 -10.5  13.1  235  41 21   8.0   4.4 |  -9.5  14.9  235  45 23   9.3   5.1
 10500  -9.3  15.3  230  38 19   8.2   4.5 |  -8.2  17.2  235  44 22   9.5   5.2
 10250  -8.7  16.3  230  36 19   8.4   4.6 |  -7.4  18.7  235  43 22   9.8   5.4
 10000  -8.1  17.4  230  34 18   8.3   4.5 |  -6.7  19.9  235  42 22   9.6   5.3
  9750  -7.5  18.5  225  33 17   8.6   4.7 |  -6.0  21.2  235  42 21   9.6   5.2
  9500  -6.8  19.8  225  32 17   9.7   5.3 |  -5.3  22.5  235  41 21   9.9   5.4
  9250  -6.0  21.2  225  31 16  10.5   5.8 |  -4.5  23.9  235  40 21  10.5   5.8
  9000  -5.3  22.5  225  30 16   9.3   5.1 |  -3.8  25.2  235  39 20   9.1   5.0
  8750  -4.6  23.7  225  30 15   9.1   5.0 |  -3.2  26.2  230  39 20   8.3   4.5
  8500  -3.9  25.0  225  29 15  10.3   5.7 |  -2.5  27.5  230  38 19   9.8   5.4
  8250  -3.1  26.4  225  29 15  11.1   6.1 |  -1.7  28.9  230  36 19  11.2   6.1
  8000  -2.3  27.9  225  29 15   8.9   4.9 |  -0.9  30.4  230  35 18   8.3   4.6
  7750  -1.7  28.9  225  28 15   8.6   4.7 |  -0.4  31.3  230  34 18   7.5   4.1
  7500  -1.0  30.2  225  28 14  10.6   5.8 |   0.3  32.5  230  33 17   9.6   5.3
  7250  -0.2  31.6  225  27 14  10.0   5.5 |   0.9  33.6  230  31 16   8.8   4.8
  7000   0.5  32.9  225  27 14  10.2   5.6 |   1.6  34.9  230  30 15  10.0   5.5
  6750   1.3  34.3  225  26 13  10.1   5.6 |   2.4  36.3  230  28 14   9.7   5.3
  6500   2.0  35.6  225  25 13  10.0   5.5 |   3.0  37.4  230  26 14   8.4   4.6
  6250   2.8  37.0  225  24 12  10.3   5.7 |   3.7  38.7  230  25 13   8.8   4.8
  6000   3.5  38.3  225  23 12   9.5   5.2 |   4.3  39.7  230  23 12   9.0   4.9
  5750   4.3  39.7  225  22 11  14.2   7.8 |   5.0  41.0  230  21 11  10.1   5.5
  5500   5.8  42.4  225  21 11  24.6  13.5 |   5.8  42.4  225  19 10  11.2   6.2
  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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