Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 261248
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0548 MST Saturday, November 26, 2016

This forecast is for Saturday, November 26, 2016:

If the trigger temperature of 53.3 F/11.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 173 ft/min (0.9 m/s)
   Maximum height of thermals.................. 8021 ft MSL (3182 ft AGL)

Forecast maximum temperature................... 53.0 F/12.1 C
Time of trigger temperature.................... 1345 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................. 6984 ft MSL (2144 ft AGL)
Thermal soaring outlook for Sunday 11/27....... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:09:52 / 16:53:25 MST
Total possible sunshine........... 9 hr 43 min 32 sec (583 min 32 sec)
Altitude of sun at 12:01:47 MST... 29.81 degrees

Upper air data from rawinsonde observation taken on 11/26/2016 at 0500 MST

Freezing level.................. 4928 ft MSL (89 ft AGL)
Additional freezing level....... 8763 ft MSL (3924 ft AGL)
Convective condensation level... 19806 ft MSL (14967 ft AGL)
Lifted condensation level....... 14537 ft MSL (9698 ft AGL)
Lifted index.................... +11.1
K index......................... -41.4

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -65.0 -85.0   270   47   24   0.2   0.1   94.4 202.0    46.9      M    M
 45000  -63.7 -82.7   260   72   37   4.3   2.4   71.7 161.1    36.5      M    M
 40000  -61.7 -79.1   265   75   39  -0.8  -0.5   50.7 123.2    25.5      M    M
 38000  -58.9 -74.0   270   86   44   6.7   3.7   46.1 114.9    23.1      M    M
 36000  -56.2 -69.2   265   69   36   2.5   1.4   41.4 106.6    20.5      M    M
 34000  -52.9 -63.2   260   55   28   9.0   4.9   37.8 100.1    18.5      M    M
 32000  -47.7 -53.9   255   50   26   7.6   4.1   36.9  98.4    18.3      M    M
 30000  -42.2 -44.0   250   48   25   7.6   4.2   35.4  95.8    17.8      M    M
 29000  -39.9 -39.8   250   47   24   8.0   4.4   34.5  94.1    17.3      M    M
 28000  -37.5 -35.5   250   45   23   8.0   4.4   33.7  92.6    16.9      M    M
 27000  -35.1 -31.2   245   44   23   8.0   4.4   33.0  91.4    16.6      M    M
 26000  -32.7 -26.9   245   43   22   8.0   4.4   32.4  90.3    16.3      M    M
 25000  -30.5 -22.9   245   42   22   5.9   3.3   31.7  89.0    15.9      M    M
 24000  -28.6 -19.5   245   45   23   7.0   3.8   30.3  86.6    15.0      M    M
 23000  -26.6 -15.9   245   45   23   6.9   3.8   29.2  84.5    14.3      M    M
 22000  -24.5 -12.1   245   44   23   6.9   3.8   28.1  82.6    13.6      M    M
 21000  -22.4  -8.3   245   44   23   6.9   3.8   27.2  81.0    13.0      M    M
 20000  -20.2  -4.4   245   44   23   7.7   4.2   26.5  79.7    12.5      M    M
 19500  -19.1  -2.4   245   42   22   7.7   4.3   26.1  79.0    12.3      M    M
 19000  -17.9  -0.2   240   40   21   7.7   4.2   25.8  78.4    12.1      M    M
 18500  -16.7   1.9   240   38   20   8.3   4.6   25.5  77.9    11.9      M    M
 18000  -15.5   4.1   240   37   19   8.3   4.5   25.2  77.3    11.7      M    M
 17500  -14.2   6.4   240   36   19   8.2   4.5   24.9  76.8    11.5      M    M
 17000  -13.0   8.6   245   35   18   8.2   4.5   24.7  76.4    11.3      M    M
 16500  -11.1  12.0   245   33   17   8.2   4.5   24.3  75.8    11.2      M    M
 16000   -9.9  14.2   245   32   16   8.2   4.5   24.1  75.4    11.0      M    M
 15500   -8.7  16.3   240   31   16   8.2   4.5   23.8  74.9    10.8      M    M
 15000   -7.4  18.7   240   30   15   7.7   4.2   23.6  74.4    10.7      M    M
 14500   -6.6  20.1   235   29   15   4.7   2.6   22.9  73.2    10.1      M    M
 14000   -5.8  21.6   235   28   14   4.9   2.7   22.1  71.8     9.5      M    M
 13500   -5.1  22.8   240   27   14   5.4   2.9   21.3  70.3     8.8      M    M
 13000   -4.6  23.7   240   26   13   0.9   0.5   20.2  68.4     7.8      M    M
 12500   -4.4  24.1   240   25   13   1.4   0.7   18.8  65.9     6.6      M    M
 12000   -4.7  23.5   245   24   12 -11.1  -6.1   17.0  62.7     4.9      M    M
 11500   -5.7  21.7   240   19   10   3.5   1.9   14.4  58.0     2.5      M    M
 11000   -4.8  23.4   230   15    8   9.9   5.4   13.9  57.0     1.9      M    M
 10500   -3.4  25.9   225   16    8   9.2   5.1   13.8  56.8     1.8      M    M
 10250   -2.8  27.0   225   17    9   6.9   3.8   13.7  56.6     1.7      M    M
 10000   -2.4  27.7   220   17    9   5.3   2.9   13.3  56.0     1.4      M    M
  9750   -2.0  28.4   210   17    9   5.7   3.1   13.0  55.4     1.1      M    M
  9500   -1.6  29.1   200   17    9   5.6   3.0   12.7  54.8     0.8      M    M
  9250   -1.2  29.8   195   17    9   5.8   3.2   12.4  54.2     0.4      M    M
  9000   -0.7  30.7   185   18    9   8.1   4.4   12.1  53.8     0.2      M    M
  8750   -0.0  32.0   180   17    9   9.4   5.2   12.1  53.7     0.1      M    M
  8500    0.7  33.3   180   17    9   9.1   5.0   12.0  53.6     0.1      M    M
  8250    1.3  34.3   175   16    8   8.9   4.9   12.0  53.6     0.1      M    M
  8000    2.0  35.6   170   16    8  10.1   5.5   11.9  53.5     0.0      M    M
  7750    2.5  36.5   165   16    8  -2.5  -1.4   11.7  53.0    -0.2    152  0.8
  7500    1.8  35.2   155   17    9  -6.0  -3.3   10.3  50.5    -1.6    165  0.8
  7250    2.0  35.6   150   18    9   6.4   3.5    9.7  49.4    -2.2    154  0.8
  7000    2.3  36.1   145   19   10  -2.4  -1.3    9.2  48.6    -2.7    137  0.7
  6750    1.8  35.2   145   20   10  -4.4  -2.4    8.0  46.3    -3.9    144  0.7
  6500    1.9  35.4   145   20   10   6.8   3.7    7.4  45.3    -4.5    132  0.7
  6250    2.5  36.5   150   21   11   5.8   3.2    7.2  45.0    -4.7    109  0.6
  6000    2.7  36.9   150   22   11   2.1   1.2    6.7  44.1    -5.2     94  0.5
  5750    2.8  37.0   145   19   10   2.1   1.1    6.1  43.0    -5.8     83  0.4
  5500    3.0  37.4   135   16    8   2.3   1.3    5.6  42.0    -6.4     71  0.4
  5250    3.1  37.6   125   13    7   1.4   0.8    5.0  41.0    -7.0     60  0.3
  5000    2.6  36.7   110   11    6 -19.1 -10.5    3.8  38.9    -8.3     67  0.3

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

           11/26/2016 at 0800 MST          |       11/26/2016 at 1100 MST
                                           |
K index... -20.7  LI... +5.5               | K index... -29.2  LI... +6.2
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 -64.8 -84.6  270  58 30   0.7   0.4 | -65.9 -86.6  260  61 31  -0.1  -0.0
 45000 -63.7 -82.7  270  76 39   1.5   0.8 | -65.8 -86.4  260  85 44   2.9   1.6
 40000 -60.8 -77.4  275  79 41   2.0   1.1 | -60.2 -76.4  265  83 43   3.7   2.0
 38000 -57.9 -72.2  275  76 39   5.6   3.1 | -56.9 -70.4  265  79 41   5.5   3.0
 36000 -54.5 -66.1  270  71 37   5.6   3.1 | -53.6 -64.5  265  73 38   5.5   3.0
 34000 -50.9 -59.6  270  66 34   6.8   3.7 | -49.7 -57.5  260  68 35   7.9   4.3
 32000 -46.8 -52.2  260  58 30   6.8   3.7 | -45.0 -49.0  260  64 33   7.8   4.3
 30000 -42.3 -44.1  255  54 28   8.7   4.8 | -40.5 -40.9  255  59 30   7.0   3.8
 29000 -39.7 -39.5  255  53 27   8.7   4.7 | -38.4 -37.1  255  56 29   7.0   3.8
 28000 -37.1 -34.8  250  52 27   8.7   4.8 | -36.3 -33.3  250  53 27   7.0   3.8
 27000 -34.6 -30.3  250  51 26   7.0   3.8 | -34.2 -29.6  250  50 26   7.3   4.0
 26000 -32.5 -26.5  250  48 25   7.0   3.9 | -32.0 -25.6  250  48 25   7.3   4.0
 25000 -30.4 -22.7  250  46 23   7.0   3.9 | -29.8 -21.6  245  46 23   7.3   4.0
 24000 -28.3 -18.9  250  43 22   6.5   3.6 | -27.6 -17.7  240  44 22   6.5   3.6
 23000 -26.4 -15.5  250  40 21   6.2   3.4 | -25.8 -14.4  240  40 21   5.9   3.3
 22000 -24.5 -12.1  250  38 19   6.2   3.4 | -23.6 -10.5  235  36 19   6.0   3.3
 21000 -22.0  -7.6  245  36 18   7.7   4.2 | -21.5  -6.7  235  34 18   7.8   4.3
 20000 -19.7  -3.5  245  36 18   7.7   4.2 | -19.2  -2.6  235  34 18   7.8   4.3
 19500 -18.5  -1.3  245  35 18   7.7   4.2 | -18.0  -0.4  235  34 17   7.8   4.3
 19000 -17.3   0.9  245  35 18   7.9   4.3 | -16.8   1.8  230  34 17   7.8   4.3
 18500 -16.1   3.0  245  35 18   8.4   4.6 | -15.7   3.7  230  33 17   7.8   4.3
 18000 -14.8   5.4  245  35 18   8.5   4.7 | -14.5   5.9  230  33 17   7.8   4.3
 17500 -13.6   7.5  240  35 18   7.7   4.2 | -13.3   8.1  230  32 17   8.2   4.5
 17000 -12.5   9.5  240  34 17   7.6   4.2 | -12.1  10.2  225  31 16   8.2   4.5
 16500 -11.3  11.7  240  33 17   7.8   4.3 | -10.8  12.6  225  30 15   7.9   4.3
 16000 -10.1  13.8  240  31 16   8.1   4.4 |  -9.8  14.4  225  28 15   7.1   3.9
 15500  -8.9  16.0  240  29 15   7.9   4.3 |  -8.7  16.3  220  27 14   7.1   3.9
 15000  -7.9  17.8  235  28 14   5.8   3.2 |  -7.7  18.1  220  26 14   5.7   3.1
 14500  -7.0  19.4  235  26 13   6.2   3.4 |  -6.9  19.6  220  26 13   6.2   3.4
 14000  -6.3  20.7  235  24 13   3.6   2.0 |  -6.3  20.7  220  25 13   1.6   0.9
 13500  -5.7  21.7  235  23 12   4.0   2.2 |  -6.0  21.2  220  24 12   1.7   1.0
 13000  -5.3  22.5  235  22 11   1.9   1.1 |  -5.8  21.6  215  22 11   2.2   1.2
 12500  -5.1  22.8  230  20 10   1.9   1.0 |  -5.5  22.1  215  21 11   2.3   1.3
 12000  -4.7  23.5  230  19 10   4.3   2.3 |  -5.1  22.8  215  20 10   5.7   3.1
 11500  -4.1  24.6  225  18  9   4.6   2.5 |  -4.2  24.4  215  19 10   6.5   3.5
 11000  -3.4  25.9  220  17  9   7.3   4.0 |  -3.2  26.2  215  19 10   7.5   4.1
 10500  -2.2  28.0  220  17  9   7.9   4.3 |  -2.1  28.2  215  20 10   8.5   4.7
 10250  -1.7  28.9  220  17  9   6.4   3.5 |  -1.5  29.3  210  20 10   4.5   2.5
 10000  -1.3  29.7  215  16  8   6.1   3.4 |  -1.3  29.7  210  20 10   4.6   2.6
  9750  -0.7  30.7  215  16  8   7.8   4.3 |  -0.7  30.7  210  20 10   9.5   5.2
  9500  -0.2  31.6  215  16  8   8.0   4.4 |  -0.0  32.0  210  19 10   9.5   5.2
  9250   0.4  32.7  215  16  8   7.0   3.8 |   0.6  33.1  210  19 10   7.4   4.1
  9000   0.9  33.6  210  16  8   6.0   3.3 |   1.1  34.0  205  18 10   5.3   2.9
  8750   1.4  34.5  210  15  8   6.2   3.4 |   1.5  34.7  205  18  9   7.1   3.9
  8500   1.8  35.2  210  14  7   5.9   3.2 |   2.1  35.8  200  17  9   7.5   4.1
  8250   2.2  36.0  205  14  7   5.0   2.8 |   2.6  36.7  200  17  9   6.3   3.5
  8000   2.6  36.7  200  14  7   4.7   2.6 |   3.1  37.6  195  16  8   5.7   3.1
  7750   2.9  37.2  200  14  7   4.3   2.4 |   3.5  38.3  190  16  8   5.1   2.8
  7500   3.2  37.8  195  14  7   2.8   1.5 |   3.8  38.8  185  15  8   3.3   1.8
  7250   3.4  38.1  185  13  7   2.0   1.1 |   4.0  39.2  180  14  7   2.3   1.2
  7000   3.6  38.5  180  13  7   2.2   1.2 |   4.2  39.6  175  13  7   2.2   1.2
  6750   3.7  38.7  175  13  7   1.8   1.0 |   4.3  39.7  165  12  6   2.1   1.2
  6500   3.8  38.8  165  12  6  -1.2  -0.7 |   4.6  40.3  160  11  6   5.0   2.7
  6250   3.6  38.5  160  10  5  -2.6  -1.4 |   5.1  41.2  160  10  5   7.6   4.1
  6000   3.4  38.1  145   9  5  -3.6  -2.0 |   5.6  42.1  155   8  4   5.7   3.1
  5750   2.7  36.9  135   8  4 -19.5 -10.7 |   6.1  43.0  155   6  3  10.5   5.8
  5500   0.3  32.5  120   6  3 -39.9 -21.9 |   7.3  45.1  150   6  3  21.2  11.7
  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

           11/26/2016 at 1400 MST          |       11/26/2016 at 1700 MST
                                           |
K index... -27.2  LI... +6.9               | K index... -13.8  LI... +6.9
CAPE... 0.0  CIN... -1.2                   | 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 -66.2 -87.2  255  66 34  -0.4  -0.2 | -66.3 -87.3  260  64 33  -0.1  -0.1
 45000 -66.7 -88.1  260  91 47   2.9   1.6 | -66.3 -87.3  255  90 46   3.7   2.0
 40000 -58.8 -73.8  260 111 57   5.0   2.7 | -57.8 -72.0  255 141 73   5.4   3.0
 38000 -55.7 -68.3  260 104 54   5.4   2.9 | -54.3 -65.7  255 139 72   6.0   3.3
 36000 -52.5 -62.5  260  90 46   5.4   2.9 | -50.7 -59.3  255 128 66   6.0   3.3
 34000 -48.9 -56.0  255  78 40   7.3   4.0 | -47.1 -52.8  255 114 59   5.9   3.2
 32000 -44.5 -48.1  255  69 36   7.3   4.0 | -43.6 -46.5  250  93 48   5.9   3.2
 30000 -40.2 -40.4  250  61 31   7.2   4.0 | -40.0 -40.0  250  72 37   6.8   3.7
 29000 -38.0 -36.4  250  57 30   7.2   4.0 | -38.0 -36.4  245  63 33   6.8   3.7
 28000 -35.3 -31.5  245  53 27   7.2   4.0 | -35.9 -32.6  235  55 28   6.8   3.7
 27000 -33.2 -27.8  240  50 26   6.1   3.4 | -33.5 -28.3  225  47 24   4.5   2.4
 26000 -31.3 -24.3  240  48 24   6.2   3.4 | -32.2 -26.0  230  48 25   4.5   2.5
 25000 -29.4 -20.9  240  45 23   6.2   3.4 | -30.8 -23.4  235  49 25   4.6   2.5
 24000 -27.6 -17.7  235  42 22   6.0   3.3 | -29.4 -20.9  235  50 26   7.2   3.9
 23000 -25.8 -14.4  235  41 21   5.9   3.2 | -26.9 -16.4  235  44 23   8.6   4.7
 22000 -24.1 -11.4  230  40 21   5.9   3.2 | -24.3 -11.7  230  39 20   8.6   4.7
 21000 -22.0  -7.6  230  39 20   9.4   5.1 | -21.7  -7.1  225  35 18   8.5   4.6
 20000 -19.3  -2.7  230  39 20   9.0   4.9 | -19.2  -2.6  225  35 18   8.5   4.6
 19500 -18.0  -0.4  230  39 20   9.0   4.9 | -17.9  -0.2  225  35 18   8.5   4.7
 19000 -16.6   2.1  230  38 20   9.1   5.0 | -16.6   2.1  225  35 18   8.5   4.7
 18500 -15.3   4.5  230  38 19   8.0   4.4 | -15.4   4.3  225  36 18   7.9   4.3
 18000 -14.1   6.6  230  37 19   7.9   4.3 | -14.2   6.4  225  37 19   7.7   4.2
 17500 -13.0   8.6  230  36 19   7.8   4.3 | -13.0   8.6  220  39 20   7.6   4.1
 17000 -11.8  10.8  230  35 18   7.6   4.2 | -12.0  10.4  220  39 20   6.7   3.7
 16500 -10.7  12.7  225  33 17   7.7   4.2 | -11.0  12.2  220  38 19   6.8   3.7
 16000  -9.6  14.7  225  31 16   6.9   3.8 | -10.0  14.0  220  37 19   5.9   3.2
 15500  -8.5  16.7  225  30 15   7.0   3.8 |  -9.2  15.4  225  36 18   5.8   3.2
 15000  -7.5  18.5  225  29 15   5.8   3.2 |  -8.3  17.1  225  35 18   5.4   3.0
 14500  -6.7  19.9  225  28 15   5.3   2.9 |  -7.5  18.5  225  34 17   5.2   2.8
 14000  -5.9  21.4  220  28 15   4.0   2.2 |  -6.8  19.8  225  33 17   4.7   2.6
 13500  -5.4  22.3  220  26 13   2.5   1.4 |  -6.2  20.8  220  32 16   3.5   1.9
 13000  -5.1  22.8  220  25 13   1.9   1.0 |  -5.5  22.1  220  30 15   3.9   2.1
 12500  -4.9  23.2  220  23 12   1.8   1.0 |  -4.9  23.2  220  29 15   4.0   2.2
 12000  -4.5  23.9  220  22 11   5.4   3.0 |  -4.3  24.3  215  28 14   4.9   2.7
 11500  -3.6  25.5  215  21 11   5.9   3.2 |  -3.6  25.5  210  27 14   5.3   2.9
 11000  -2.7  27.1  215  21 11   7.2   4.0 |  -2.8  27.0  210  26 13   6.2   3.4
 10500  -1.6  29.1  215  21 11   8.0   4.4 |  -1.8  28.8  205  24 13   5.9   3.3
 10250  -1.1  30.0  215  22 11   4.9   2.7 |  -1.3  29.7  205  23 12   9.3   5.1
 10000  -0.8  30.6  210  21 11   6.2   3.4 |  -0.5  31.1  205  22 12  10.6   5.8
  9750  -0.1  31.8  210  20 10  10.1   5.5 |   0.1  32.2  205  22 11   8.2   4.5
  9500   0.5  32.9  205  20 10   9.6   5.3 |   0.7  33.3  205  21 11   9.0   4.9
  9250   1.2  34.2  205  19 10   7.7   4.2 |   1.4  34.5  200  20 10   8.1   4.5
  9000   1.7  35.1  200  18  9   6.6   3.6 |   2.0  35.6  200  19 10   8.0   4.4
  8750   2.2  36.0  200  18  9   8.2   4.5 |   2.6  36.7  200  19 10   8.5   4.7
  8500   2.8  37.0  195  17  9   7.6   4.2 |   3.2  37.8  195  18  9   8.4   4.6
  8250   3.4  38.1  190  16  8   6.7   3.7 |   3.8  38.8  190  18  9   8.3   4.5
  8000   3.8  38.8  185  15  8   5.9   3.2 |   4.4  39.9  190  17  9   7.4   4.0
  7750   4.2  39.6  180  14  7   5.4   3.0 |   4.9  40.8  185  17  9   6.5   3.6
  7500   4.7  40.5  175  12  6   6.3   3.5 |   5.4  41.7  180  17  9   6.4   3.5
  7250   5.2  41.4  170  11  6   7.7   4.2 |   5.9  42.6  175  16  8   6.5   3.6
  7000   5.8  42.4  170  10  5   7.8   4.3 |   6.4  43.5  175  16  8   6.4   3.5
  6750   6.4  43.5  170   9  5   8.5   4.7 |   6.8  44.2  170  15  8   6.1   3.3
  6500   7.1  44.8  170   9  4   9.9   5.4 |   7.3  45.1  165  14  7   5.7   3.1
  6250   7.8  46.0  170   8  4  10.9   6.0 |   7.6  45.7  165  13  7   4.8   2.6
  6000   8.6  47.5  170   8  4   9.7   5.3 |   8.0  46.4  160  12  6   7.0   3.9
  5750   9.3  48.7  170   7  4   8.6   4.7 |   8.5  47.3  160  10  5   2.8   1.5
  5500   9.9  49.8  170   7  4   8.9   4.9 |   8.2  46.8  150   8  4  -8.8  -4.8
  5250  10.6  51.1  170   7  3   8.9   4.9 |   7.4  45.3  150   6  3 -12.1  -6.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  Note that some elevations in numerical weather prediction models
differ from actual station elevations, which can lead to data which appear
to be below ground.  Erroneous data such as these should not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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