Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 161552
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0852 MST Thursday, November 16, 2017

This forecast is for Thursday, November 16, 2017:

If the trigger temperature of 64.0 F/17.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6961 ft MSL (2122 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5889 ft MSL (1050 ft AGL)
Thermal soaring outlook for Friday 11/17....... Poor

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

Remarks...

Sunrise/Sunset.................... 06:58:50 / 16:59:01 MST
Total possible sunshine........... 10 hr 0 min 10 sec (600 min 10 sec)
Altitude of sun at 11:59:07 MST... 32.01 degrees

Upper air data from rawinsonde observation taken on 11/16/2017 at 0500 MST

Freezing level.................. 12078 ft MSL (7239 ft AGL)
Convective condensation level... 21824 ft MSL (16985 ft AGL)
Lifted condensation level....... 15943 ft MSL (11104 ft AGL)
Lifted index.................... +11.0
K index......................... +5.0

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  -67.2 -89.0   270  103   53   1.4   0.8   86.8 188.3    40.1      M    M
 45000  -62.5 -80.5   275  115   59   7.2   4.0   70.0 158.0    32.7      M    M
 40000  -55.0 -67.0   275  126   65   3.4   1.8   58.9 138.0    27.7      M    M
 38000  -54.2 -65.6   275  123   63  -4.8  -2.6   51.3 124.3    23.3      M    M
 36000  -51.8 -61.2   280   99   51   6.3   3.4   46.2 115.1    20.4      M    M
 34000  -48.2 -54.8   275   80   41   8.5   4.6   41.9 107.3    18.0      M    M
 32000  -43.0 -45.4   275   75   39   8.6   4.7   40.8 105.5    17.7      M    M
 30000  -37.9 -36.2   275   74   38   8.6   4.7   40.1 104.2    17.6      M    M
 29000  -35.4 -31.7   275   71   37   6.7   3.7   39.4 102.9    17.3      M    M
 28000  -33.3 -27.9   270   68   35   9.6   5.3   38.4 101.0    16.7      M    M
 27000  -32.2 -26.0   270   66   34   9.8   5.4   36.0  96.8    15.0      M    M
 26000  -30.0 -22.0   265   63   33   6.1   3.3   35.1  95.2    14.5      M    M
 25000  -27.5 -17.5   265   61   31   9.1   5.0   34.7  94.4    14.3      M    M
 24000  -24.7 -12.5   265   61   31   9.3   5.1   34.5  94.0    14.3      M    M
 23000  -22.0  -7.6   265   64   33   7.9   4.4   34.1  93.4    14.2      M    M
 22000  -19.7  -3.5   265   60   31   7.9   4.4   33.4  92.1    13.8      M    M
 21000  -17.3   0.9   260   56   29   7.9   4.3   32.8  91.0    13.5      M    M
 20000  -14.8   5.4   260   51   26   6.7   3.7   32.3  90.1    13.2      M    M
 19500  -14.0   6.8   260   50   26   5.9   3.2   31.6  88.8    12.6      M    M
 19000  -13.7   7.3   260   50   26  -5.7  -3.1   30.2  86.3    11.5      M    M
 18500  -14.8   5.4   260   47   24   7.8   4.3   26.6  79.8     8.3      M    M
 18000  -13.9   7.0   260   43   22   6.0   3.3   25.9  78.6     7.7      M    M
 17500  -13.1   8.4   255   40   21   5.8   3.2   25.2  77.4     7.2      M    M
 17000  -12.1  10.2   255   37   19   7.8   4.3   24.7  76.5     6.7      M    M
 16500  -11.0  12.2   250   34   18   7.6   4.2   24.4  75.9     6.4      M    M
 16000   -9.8  14.4   250   32   16   8.4   4.6   24.1  75.4     6.2      M    M
 15500   -8.5  16.7   250   30   15   8.3   4.6   23.8  74.9     6.0      M    M
 15000   -7.3  18.9   250   28   15   8.3   4.6   23.6  74.5     5.9      M    M
 14500   -6.0  21.2   250   27   14   8.3   4.6   23.4  74.1     5.7      M    M
 14000   -4.8  23.4   250   25   13   8.3   4.6   23.2  73.8     5.6      M    M
 13500   -3.5  25.7   250   25   13   8.3   4.6   22.9  73.3     5.4      M    M
 13000   -2.2  28.0   250   25   13   8.3   4.6   22.7  72.8     5.2      M    M
 12500   -1.0  30.2   250   25   13   8.3   4.6   22.4  72.4     5.0      M    M
 12000    0.3  32.5   250   25   13   8.3   4.6   22.2  72.0     4.8      M    M
 11500    1.5  34.7   250   23   12   8.3   4.5   22.0  71.5     4.6      M    M
 11000    1.8  35.2   250   22   11  -3.6  -2.0   20.7  69.3     3.5      M    M
 10500    1.9  35.4   245   20   10   5.0   2.7   19.2  66.5     2.1      M    M
 10250    2.4  36.3   245   19   10   7.3   4.0   18.9  66.1     1.8      M    M
 10000    2.9  37.2   245   17    9   7.6   4.2   18.8  65.8     1.7      M    M
  9750    3.5  38.3   240   15    8   8.1   4.4   18.6  65.5     1.5      M    M
  9500    4.1  39.4   235   12    6   8.0   4.4   18.5  65.3     1.4      M    M
  9250    4.7  40.5   230   10    5   8.0   4.4   18.3  65.0     1.3      M    M
  9000    5.3  41.5   215    8    4   8.0   4.4   18.2  64.8     1.2      M    M
  8750    5.9  42.6   210    7    4   8.0   4.4   18.1  64.5     1.0      M    M
  8500    6.5  43.7   205    6    3   8.0   4.4   17.9  64.3     0.9      M    M
  8250    7.1  44.8   200    6    3   8.0   4.4   17.8  64.1     0.8      M    M
  8000    7.7  45.9   190    5    3   8.0   4.4   17.7  63.8     0.6      M    M
  7750    8.3  46.9   185    5    3   8.0   4.4   17.5  63.6     0.5      M    M
  7500    8.9  48.0   185    5    3   8.0   4.4   17.4  63.3     0.4      M    M
  7250    9.5  49.1   180    6    3   8.1   4.5   17.2  63.0     0.2      M    M
  7000   10.1  50.2   175    6    3   7.5   4.1   17.1  62.8     0.1      M    M
  6750   10.6  51.1   170    8    4   5.8   3.2   16.9  62.4    -0.2     60  0.3
  6500   10.9  51.6   165   12    6   3.9   2.1   16.5  61.7    -0.5     41  0.2
  6250   11.3  52.3   160   15    8   8.3   4.5   16.1  61.0    -0.9     23  0.1
  6000   11.6  52.9   160   18    9  -7.4  -4.1   15.8  60.4    -1.3      5  0.0
  5750   10.0  50.0   155   16    8 -28.7 -15.7   13.4  56.1    -3.6     47  0.2
  5500    8.2  46.8   150   13    7 -15.6  -8.6   10.8  51.4    -6.2     94  0.5
  5250    7.7  45.9   135   10    5   0.4   0.2    9.6  49.3    -7.4    100  0.5
  5000    7.3  45.1   115    8    4 -21.5 -11.8    8.4  47.2    -8.6    106  0.5

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

           11/16/2017 at 0800 MST          |       11/16/2017 at 1100 MST
                                           |
K index... +9.9  LI... +4.7                | K index... +13.7  LI... +2.9
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -67.9 -90.2  275  86 44   3.6   2.0 | -67.4 -89.3  270  83 43   3.4   1.9
 45000 -62.4 -80.3  275  98 50   4.8   2.6 | -61.7 -79.1  270  94 49   5.0   2.8
 40000 -54.9 -66.8  280 124 64   4.9   2.7 | -54.1 -65.4  275 119 61   5.1   2.8
 38000 -52.6 -62.7  280 120 62   3.5   1.9 | -52.0 -61.6  275 119 61   3.1   1.7
 36000 -50.5 -58.9  280 113 58   3.5   1.9 | -50.1 -58.2  275 115 59   3.1   1.7
 34000 -47.4 -53.3  280 104 54   7.7   4.2 | -47.2 -53.0  275 109 56   7.5   4.1
 32000 -42.8 -45.0  280  93 48   7.6   4.2 | -42.7 -44.9  275 100 51   7.4   4.1
 30000 -38.2 -36.8  280  85 44   7.9   4.3 | -37.7 -35.9  275  91 47   7.4   4.0
 29000 -35.8 -32.4  280  83 42   7.9   4.3 | -35.5 -31.9  275  88 45   7.4   4.1
 28000 -32.8 -27.0  275  80 41   7.9   4.3 | -33.3 -27.9  275  84 43   7.4   4.1
 27000 -30.6 -23.1  275  76 39   6.9   3.8 | -31.1 -24.0  275  81 42   7.4   4.0
 26000 -28.5 -19.3  275  72 37   7.0   3.8 | -28.9 -20.0  270  76 39   7.4   4.0
 25000 -26.5 -15.7  275  68 35   7.0   3.8 | -26.7 -16.1  270  71 37   7.4   4.0
 24000 -24.3 -11.7  270  64 33   7.4   4.1 | -24.6 -12.3  270  67 35   7.0   3.8
 23000 -22.1  -7.8  270  61 31   7.4   4.0 | -22.5  -8.5  265  64 33   7.0   3.8
 22000 -19.9  -3.8  270  58 30   7.4   4.0 | -20.4  -4.7  265  61 32   7.0   3.8
 21000 -17.9  -0.2  270  55 28   5.5   3.0 | -18.4  -1.1  265  58 30   5.9   3.2
 20000 -16.3   2.7  265  50 26   5.6   3.1 | -16.6   2.1  260  54 28   6.0   3.3
 19500 -15.5   4.1  265  48 25   5.6   3.1 | -15.7   3.7  260  52 27   6.0   3.3
 19000 -14.6   5.7  265  45 23   5.7   3.2 | -14.8   5.4  260  50 26   5.9   3.2
 18500 -13.9   7.0  265  43 22   4.9   2.7 | -13.9   7.0  260  48 25   6.8   3.7
 18000 -13.2   8.2  260  41 21   5.0   2.7 | -12.9   8.8  260  46 24   6.8   3.7
 17500 -12.4   9.7  260  39 20   5.7   3.1 | -11.9  10.6  255  44 23   6.9   3.8
 17000 -11.5  11.3  260  37 19   6.9   3.8 | -10.8  12.6  255  42 22   7.1   3.9
 16500 -10.5  13.1  260  36 19   6.9   3.8 |  -9.8  14.4  255  40 21   7.2   3.9
 16000  -9.4  15.1  255  35 18   8.0   4.4 |  -8.8  16.2  250  39 20   6.9   3.8
 15500  -8.2  17.2  255  34 18   7.9   4.3 |  -7.8  18.0  250  39 20   6.9   3.8
 15000  -7.1  19.2  250  33 17   7.6   4.2 |  -6.8  19.8  255  38 20   6.7   3.7
 14500  -5.9  21.4  250  32 17   7.6   4.1 |  -5.8  21.6  255  37 19   6.6   3.6
 14000  -4.8  23.4  250  31 16   7.2   3.9 |  -4.4  24.1  255  36 18   7.1   3.9
 13500  -3.3  26.1  245  30 15   6.9   3.8 |  -3.4  25.9  255  35 18   7.1   3.9
 13000  -2.3  27.9  245  29 15   6.2   3.4 |  -2.3  27.9  255  34 17   6.9   3.8
 12500  -1.3  29.7  245  28 15   6.2   3.4 |  -1.3  29.7  250  33 17   6.9   3.8
 12000  -0.4  31.3  240  28 14   6.3   3.5 |  -0.4  31.3  250  32 16   5.7   3.1
 11500   0.5  32.9  240  27 14   6.4   3.5 |   0.4  32.7  245  32 16   5.5   3.0
 11000   1.4  34.5  240  27 14   5.3   2.9 |   1.2  34.2  245  31 16   4.3   2.4
 10500   2.2  36.0  235  26 13   4.5   2.5 |   1.8  35.2  245  32 16   3.5   1.9
 10250   2.6  36.7  235  25 13   7.8   4.3 |   2.1  35.8  240  32 17   6.6   3.6
 10000   3.3  37.9  235  25 13   8.9   4.9 |   2.8  37.0  240  32 16   8.3   4.6
  9750   3.9  39.0  235  24 12   6.3   3.5 |   3.3  37.9  240  30 16   6.2   3.4
  9500   4.4  39.9  230  23 12   7.2   3.9 |   3.8  38.8  235  29 15   7.1   3.9
  9250   4.9  40.8  230  22 11   6.3   3.4 |   4.4  39.9  235  28 14   5.5   3.0
  9000   5.3  41.5  230  21 11   5.6   3.1 |   4.7  40.5  235  26 13   5.7   3.1
  8750   5.8  42.4  225  20 11   5.8   3.2 |   5.3  41.5  230  25 13   7.1   3.9
  8500   6.2  43.2  220  20 10   5.8   3.2 |   5.8  42.4  230  23 12   7.0   3.8
  8250   6.6  43.9  220  20 10   5.4   3.0 |   6.3  43.3  230  22 11   5.2   2.8
  8000   7.0  44.6  215  20 10   4.3   2.3 |   6.6  43.9  225  21 11   3.4   1.9
  7750   7.3  45.1  210  20 10   3.6   2.0 |   6.9  44.4  220  19 10   3.6   2.0
  7500   7.5  45.5  205  21 11   2.9   1.6 |   7.2  45.0  210  17  9   3.9   2.1
  7250   7.7  45.9  195  21 11   1.8   1.0 |   7.5  45.5  205  15  8   4.8   2.6
  7000   7.8  46.0  190  21 11   0.8   0.4 |   7.9  46.2  200  13  7   5.4   3.0
  6750   7.9  46.2  185  22 11   1.6   0.9 |   8.3  46.9  190  12  6   5.0   2.8
  6500   7.9  46.2  180  22 11  -5.7  -3.1 |   8.8  47.8  190  11  6   8.4   4.6
  6250   7.1  44.8  175  19 10 -12.3  -6.7 |   9.6  49.3  190  11  6  11.5   6.3
  6000   6.2  43.2  165  17  9  -9.9  -5.4 |  10.4  50.7  190  10  5  10.3   5.6
  5750   5.5  41.9  155  13  7 -10.3  -5.6 |  11.1  52.0  190  10  5  10.1   5.5
  5500   4.7  40.5  140  10  5 -11.7  -6.4 |  11.9  53.4  190   9  5  10.6   5.8
  5250   3.7  38.7  135   8  4 -12.5  -6.9 |  12.7  54.9  190   9  5  11.3   6.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           11/16/2017 at 1400 MST          |       11/16/2017 at 1700 MST
                                           |
K index... +10.3  LI... +2.8               | K index... +17.1  LI... +1.6
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -66.9 -88.4  265  85 44   3.6   2.0 | -65.7 -86.3  265  81 42   2.8   1.5
 45000 -61.1 -78.0  265  98 50   4.4   2.4 | -61.4 -78.5  265  99 51   3.4   1.9
 40000 -54.4 -65.9  270 124 64   4.4   2.4 | -56.1 -69.0  270 128 66   3.4   1.9
 38000 -52.4 -62.3  270 124 64   3.1   1.7 | -53.6 -64.5  270 129 66   4.3   2.3
 36000 -50.5 -58.9  270 121 62   3.1   1.7 | -51.1 -60.0  270 127 65   4.3   2.3
 34000 -47.5 -53.5  275 116 60   8.1   4.4 | -47.7 -53.9  275 121 62   7.9   4.3
 32000 -42.7 -44.9  270 107 55   8.0   4.4 | -42.9 -45.2  275 110 56   7.9   4.3
 30000 -37.5 -35.5  270  99 51   7.4   4.1 | -38.2 -36.8  275 100 51   8.0   4.4
 29000 -35.2 -31.4  270  96 49   7.4   4.1 | -35.2 -31.4  275  96 49   8.0   4.4
 28000 -33.0 -27.4  270  92 48   7.4   4.1 | -32.8 -27.0  270  93 48   8.0   4.4
 27000 -30.9 -23.6  270  89 46   6.8   3.7 | -30.5 -22.9  270  90 46   6.9   3.8
 26000 -28.8 -19.8  265  86 44   6.8   3.7 | -28.4 -19.1  270  88 45   7.0   3.8
 25000 -26.8 -16.2  265  82 42   6.8   3.7 | -26.3 -15.3  265  85 44   7.0   3.8
 24000 -24.8 -12.6  265  79 41   6.7   3.7 | -24.2 -11.6  265  83 43   6.8   3.7
 23000 -22.8  -9.0  265  75 39   6.7   3.7 | -22.2  -8.0  265  80 41   6.8   3.7
 22000 -20.8  -5.4  265  72 37   6.7   3.7 | -20.2  -4.4  260  78 40   6.9   3.8
 21000 -18.8  -1.8  265  68 35   6.9   3.8 | -18.2  -0.8  260  75 39   5.5   3.0
 20000 -16.7   1.9  265  64 33   6.9   3.8 | -16.6   2.1  260  70 36   5.7   3.1
 19500 -15.7   3.7  260  62 32   6.9   3.8 | -15.8   3.6  260  68 35   5.7   3.1
 19000 -14.7   5.5  260  60 31   6.9   3.8 | -14.9   5.2  260  65 34   5.7   3.1
 18500 -13.6   7.5  260  58 30   6.6   3.6 | -14.1   6.6  260  63 32   5.8   3.2
 18000 -12.7   9.1  260  55 28   6.6   3.6 | -13.2   8.2  260  60 31   5.8   3.2
 17500 -11.7  10.9  260  51 26   6.7   3.7 | -12.3   9.9  260  57 29   5.9   3.3
 17000 -10.7  12.7  255  48 25   6.9   3.8 | -11.4  11.5  260  54 28   6.2   3.4
 16500  -9.6  14.7  255  45 23   6.8   3.7 | -10.5  13.1  260  51 26   6.1   3.3
 16000  -8.5  16.7  255  43 22   7.6   4.2 |  -9.5  14.9  260  49 25   7.0   3.9
 15500  -7.4  18.7  255  43 22   7.6   4.2 |  -8.5  16.7  260  46 24   7.0   3.8
 15000  -6.3  20.7  250  42 21   7.0   3.9 |  -7.5  18.5  260  44 23   7.2   4.0
 14500  -4.8  23.4  250  41 21   7.1   3.9 |  -6.4  20.5  255  42 22   7.3   4.0
 14000  -4.0  24.8  250  41 21   5.0   2.7 |  -5.4  22.3  255  40 21   7.2   4.0
 13500  -3.3  26.1  250  42 21   5.2   2.8 |  -3.9  25.0  255  38 19   7.1   3.9
 13000  -2.6  27.3  245  42 21   5.2   2.8 |  -2.8  27.0  250  37 19   7.1   3.9
 12500  -1.8  28.8  245  41 21   5.2   2.8 |  -1.8  28.8  250  36 18   7.1   3.9
 12000  -1.0  30.2  245  40 21   6.8   3.7 |  -0.7  30.7  250  35 18   8.2   4.5
 11500   0.0  32.0  240  38 19   7.2   3.9 |   0.5  32.9  245  34 17   8.6   4.7
 11000   1.2  34.2  235  35 18   7.8   4.3 |   1.8  35.2  240  33 17   7.9   4.3
 10500   2.4  36.3  235  32 17   7.2   3.9 |   2.9  37.2  240  33 17   7.2   3.9
 10250   3.0  37.4  230  31 16  11.1   6.1 |   3.5  38.3  240  33 17   9.9   5.4
 10000   4.0  39.2  230  30 15  11.2   6.2 |   4.3  39.7  240  33 17  10.7   5.8
  9750   4.6  40.3  230  28 14   7.4   4.1 |   5.0  41.0  235  33 17   8.5   4.7
  9500   5.2  41.4  230  27 14   8.4   4.6 |   5.7  42.3  235  32 16   9.4   5.1
  9250   5.8  42.4  225  25 13   8.4   4.6 |   6.4  43.5  235  31 16   8.0   4.4
  9000   6.5  43.7  225  23 12   8.4   4.6 |   6.9  44.4  235  30 15   8.2   4.5
  8750   7.1  44.8  225  22 11   8.1   4.4 |   7.6  45.7  235  28 15   9.6   5.3
  8500   7.7  45.9  225  20 10   8.2   4.5 |   8.3  46.9  235  27 14   8.7   4.8
  8250   8.3  46.9  225  18  9   8.1   4.5 |   9.0  48.2  235  26 13  10.8   5.9
  8000   9.0  48.2  225  17  9   8.3   4.6 |   9.9  49.8  235  25 13  10.3   5.6
  7750   9.6  49.3  225  16  8   8.4   4.6 |  10.5  50.9  235  24 12   7.9   4.3
  7500  10.2  50.4  225  15  8   8.6   4.7 |  11.1  52.0  235  23 12   8.4   4.6
  7250  10.9  51.6  230  14  7   9.8   5.4 |  11.8  53.2  235  22 11   9.1   5.0
  7000  11.7  53.1  230  14  7  10.2   5.6 |  12.5  54.5  240  20 10   8.6   4.7
  6750  12.4  54.3  230  13  7   9.3   5.1 |  13.0  55.4  240  19 10   6.8   3.7
  6500  13.1  55.6  230  13  7   9.7   5.3 |  13.5  56.3  240  17  9   6.3   3.5
  6250  13.9  57.0  235  12  6  10.3   5.6 |  14.0  57.2  240  15  8   6.3   3.4
  6000  14.6  58.3  235  12  6  10.3   5.7 |  14.4  57.9  245  12  6   5.9   3.2
  5750  15.4  59.7  235  11  6  10.5   5.8 |  14.8  58.6  245   9  5   3.3   1.8
  5500  16.2  61.2  235  10  5  10.3   5.6 |  14.8  58.6  245   6  3  -5.2  -2.9
  5250  17.0  62.6  235  11  5   9.8   5.4 |  14.0  57.2  240   6  3 -14.8  -8.1
  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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