Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281326
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0626 MST Friday, November 28, 2014

This forecast is for Friday, November 28, 2014:

If the trigger temperature of 62.6 F/17.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 182 ft/min (0.9 m/s)
   Maximum height of thermals.................. 6972 ft MSL (2133 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... None
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................. 5946 ft MSL (1107 ft AGL)
Thermal soaring outlook for Saturday 11/29..... Fair

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

Remarks...

Sunrise/Sunset.................... 07:11:24 / 16:52:53 MST
Total possible sunshine........... 9 hr 41 min 29 sec (581 min 29 sec)
Altitude of sun at 12:02:17 MST... 29.55 degrees

Upper air data from rawinsonde observation taken on 11/28/2014 at 0500 MST

Freezing level.................. 4954 ft MSL (115 ft AGL)
Additional freezing level....... 12482 ft MSL (7643 ft AGL)
Convective condensation level... 19495 ft MSL (14656 ft AGL)
Lifted condensation level....... 12786 ft MSL (7947 ft AGL)
Lifted index.................... +13.7
K index......................... -9.9

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  -68.1 -90.6   290   31   16   7.7   4.2   87.0 188.6    42.6      M    M
 45000  -61.1 -78.0   285   55   28   0.6   0.3   72.8 163.0    37.1      M    M
 40000  -61.2 -78.2   300   89   46   6.8   3.7   49.5 121.1    24.5      M    M
 38000  -57.0 -70.6   300   86   45   7.0   3.9   46.8 116.3    23.4      M    M
 36000  -52.7 -62.9   295   76   39   7.0   3.9   44.4 112.0    22.4      M    M
 34000  -48.2 -54.8   290   68   35   8.8   4.8   42.7 108.9    21.7      M    M
 32000  -42.8 -45.0   300   69   36   7.7   4.2   41.1 106.0    21.2      M    M
 30000  -38.5 -37.3   295   64   33   8.5   4.7   39.1 102.4    20.2      M    M
 29000  -36.0 -32.8   295   65   33   8.4   4.6   38.6 101.4    20.0      M    M
 28000  -33.5 -28.3   290   66   34   8.4   4.6   37.9 100.3    19.8      M    M
 27000  -31.0 -23.8   290   67   34   8.4   4.6   37.4  99.3    19.6      M    M
 26000  -28.5 -19.3   290   68   35   8.1   4.5   37.0  98.6    19.5      M    M
 25000  -26.1 -15.0   290   62   32   7.9   4.3   36.3  97.3    19.1      M    M
 24000  -23.6 -10.5   290   57   29   8.6   4.7   35.7  96.3    18.9      M    M
 23000  -21.3  -6.3   285   54   28   4.6   2.5   35.0  94.9    18.5      M    M
 22000  -19.8  -3.6   280   52   27   5.1   2.8   33.2  91.8    17.3      M    M
 21000  -18.3  -0.9   275   50   26   5.7   3.2   31.6  88.8    16.2      M    M
 20000  -16.0   3.2   270   48   25   7.9   4.3   30.8  87.4    15.7      M    M
 19500  -14.8   5.4   270   47   24   7.8   4.3   30.5  86.8    15.5      M    M
 19000  -13.6   7.5   270   46   24   7.7   4.2   30.1  86.2    15.3      M    M
 18500  -12.4   9.7   270   45   23   5.8   3.2   29.9  85.7    15.1      M    M
 18000  -12.1  10.2   270   44   22   2.3   1.3   28.5  83.3    14.0      M    M
 17500  -10.8  12.6   270   42   21   7.2   4.0   27.6  81.6    13.3      M    M
 17000   -9.7  14.5   265   40   21   7.3   4.0   27.2  80.9    13.0      M    M
 16500   -8.6  16.5   265   39   20   7.3   4.0   26.8  80.2    12.7      M    M
 16000   -7.6  18.3   265   38   19   7.3   4.0   26.4  79.5    12.4      M    M
 15500   -6.5  20.3   265   36   19   7.3   4.0   26.0  78.7    12.1      M    M
 15000   -5.4  22.3   265   34   18   7.3   4.0   25.6  78.0    11.8      M    M
 14500   -4.3  24.3   265   33   17   7.3   4.0   25.2  77.3    11.5      M    M
 14000   -3.2  26.2   265   31   16   7.3   4.0   24.8  76.7    11.2      M    M
 13500   -2.1  28.2   260   31   16   7.3   4.0   24.4  75.9    10.9      M    M
 13000   -1.0  30.2   260   30   16   7.3   4.0   23.9  75.1    10.6      M    M
 12500    0.0  32.0   255   30   16   7.3   4.0   23.5  74.4    10.2      M    M
 12000    1.1  34.0   255   30   15   7.3   4.0   23.2  73.7     9.9      M    M
 11500    2.2  36.0   250   29   15   7.2   4.0   22.7  72.9     9.6      M    M
 11000    3.3  37.9   245   27   14   6.2   3.4   22.3  72.2     9.2      M    M
 10500    3.6  38.5   240   26   14  -0.9  -0.5   21.0  69.9     8.1      M    M
 10250    3.6  38.5   240   26   13   1.4   0.8   20.3  68.5     7.4      M    M
 10000    3.8  38.8   240   23   12   2.7   1.5   19.7  67.4     6.9      M    M
  9750    3.9  39.0   240   20   10   2.3   1.3   19.1  66.4     6.3      M    M
  9500    4.1  39.4   240   18    9   2.6   1.4   18.5  65.3     5.8      M    M
  9250    4.3  39.7   235   15    8   2.2   1.2   17.9  64.3     5.2      M    M
  9000    4.5  40.1   235   12    6   5.2   2.8   17.4  63.4     4.7      M    M
  8750    5.0  41.0   230   10    5   8.0   4.4   17.2  63.0     4.5      M    M
  8500    5.5  41.9   225    8    4   6.7   3.7   17.0  62.7     4.3      M    M
  8250    6.1  43.0   220    7    3   9.3   5.1   16.9  62.3     4.2      M    M
  8000    6.6  43.9   205    5    3  -0.4  -0.2   16.7  62.0     4.0      M    M
  7750    6.0  42.8   195    5    2  -8.5  -4.7   15.3  59.6     2.6      M    M
  7500    5.7  42.3   185    5    2   2.0   1.1   14.3  57.8     1.6      M    M
  7250    6.1  43.0   175    5    2   7.1   3.9   14.0  57.2     1.3      M    M
  7000    6.2  43.2   165    5    3  -9.9  -5.4   13.3  56.0     0.6      M    M
  6750    5.0  41.0   160    5    3  -9.0  -5.0   11.4  52.6    -1.3    200  1.0
  6500    5.1  41.2   155    5    3   6.0   3.3   10.8  51.5    -1.9    189  1.0
  6250    5.5  41.9   150    5    3   5.5   3.0   10.5  50.8    -2.3    171  0.9
  6000    5.8  42.4   140    5    3   2.5   1.4   10.1  50.2    -2.7    153  0.8
  5750    5.9  42.6   140    4    2   3.2   1.7    9.5  49.0    -3.3    144  0.7
  5500    5.5  41.9   140    3    2 -23.7 -13.0    8.4  47.2    -4.4    147  0.7
  5250    2.6  36.7   135    2    1 -40.0 -21.9    4.7  40.4    -8.1    228  1.2
  5000    1.0  33.8   130    1    1   0.6   0.3    2.4  36.2   -10.4    267  1.4

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

           11/28/2014 at 0800 MST          |       11/28/2014 at 1100 MST
                                           |
K index... -3.7  LI... +6.6                | K index... -5.7  LI... +7.8
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... -0.9
                                           |
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 -69.3 -92.7  290  50 26   2.6   1.4 | -69.4 -92.9  285  50 26   2.5   1.4
 45000 -65.3 -85.5  295  65 34   3.5   1.9 | -65.6 -86.1  285  63 32   3.7   2.1
 40000 -59.7 -75.5  295  83 43   3.3   1.8 | -59.7 -75.5  285  83 43   3.7   2.0
 38000 -55.8 -68.4  295  81 42   7.0   3.8 | -55.6 -68.1  285  80 41   7.2   4.0
 36000 -51.6 -60.9  295  78 40   7.0   3.8 | -51.3 -60.3  285  77 40   7.2   4.0
 34000 -47.3 -53.1  295  74 38   7.2   3.9 | -46.8 -52.2  285  73 37   7.7   4.2
 32000 -43.0 -45.4  295  68 35   7.2   3.9 | -42.2 -44.0  285  67 34   7.7   4.2
 30000 -38.5 -37.3  295  62 32   7.9   4.3 | -37.6 -35.7  285  63 32   7.7   4.2
 29000 -36.2 -33.2  290  58 30   7.9   4.4 | -35.3 -31.5  280  62 32   7.7   4.2
 28000 -33.8 -28.8  290  55 28   7.9   4.4 | -33.0 -27.4  275  61 31   7.7   4.2
 27000 -31.4 -24.5  285  52 27   8.4   4.6 | -30.2 -22.4  275  58 30   7.7   4.2
 26000 -28.2 -18.8  285  51 27   8.4   4.6 | -27.8 -18.0  270  55 28   7.7   4.2
 25000 -25.7 -14.3  280  51 26   8.3   4.6 | -25.5 -13.9  270  52 27   7.7   4.2
 24000 -23.5 -10.3  280  51 26   6.6   3.6 | -23.4 -10.1  265  51 26   6.6   3.6
 23000 -21.5  -6.7  280  52 27   6.6   3.6 | -21.4  -6.5  270  52 27   6.6   3.6
 22000 -19.5  -3.1  280  53 27   6.6   3.6 | -19.4  -2.9  270  53 28   6.7   3.7
 21000 -17.4   0.7  280  52 27   7.3   4.0 | -17.2   1.0  270  53 28   8.0   4.4
 20000 -15.2   4.6  275  51 26   7.3   4.0 | -14.8   5.4  270  52 27   8.1   4.4
 19500 -14.2   6.4  275  50 26   7.3   4.0 | -13.6   7.5  270  52 27   8.0   4.4
 19000 -13.1   8.4  275  49 25   7.2   4.0 | -12.4   9.7  270  51 26   7.8   4.3
 18500 -12.0  10.4  275  48 25   6.8   3.7 | -11.4  11.5  265  50 26   6.0   3.3
 18000 -11.0  12.2  275  46 24   6.8   3.8 | -10.5  13.1  265  49 25   6.1   3.4
 17500 -10.0  14.0  275  44 23   6.5   3.6 |  -9.6  14.7  265  47 24   5.5   3.0
 17000  -9.1  15.6  270  43 22   6.5   3.5 |  -8.8  16.2  265  45 23   5.3   2.9
 16500  -8.2  17.2  270  41 21   6.3   3.5 |  -8.0  17.6  265  44 22   5.1   2.8
 16000  -7.2  19.0  270  39 20   6.1   3.3 |  -7.4  18.7  265  42 22   4.5   2.5
 15500  -6.4  20.5  270  38 19   6.1   3.3 |  -6.7  19.9  265  41 21   4.3   2.4
 15000  -5.4  22.3  270  37 19   6.6   3.6 |  -5.9  21.4  265  39 20   6.3   3.4
 14500  -4.4  24.1  270  36 18   6.5   3.6 |  -5.0  23.0  265  38 19   6.0   3.3
 14000  -3.4  25.9  270  35 18   7.1   3.9 |  -4.1  24.6  265  37 19   6.9   3.8
 13500  -2.4  27.7  270  34 17   7.1   3.9 |  -3.0  26.6  265  36 18   7.1   3.9
 13000  -0.7  30.7  270  33 17   7.7   4.2 |  -1.4  29.5  270  34 18   8.0   4.4
 12500   0.4  32.7  270  32 16   7.8   4.3 |  -0.2  31.6  265  34 17   8.0   4.4
 12000   1.5  34.7  265  31 16   6.4   3.5 |   0.9  33.6  265  33 17   7.3   4.0
 11500   2.5  36.5  265  29 15   6.7   3.7 |   2.1  35.8  265  31 16   7.7   4.2
 11000   3.3  37.9  260  28 14   4.2   2.3 |   3.0  37.4  260  29 15   4.8   2.6
 10500   3.9  39.0  255  26 13   4.4   2.4 |   3.7  38.7  255  26 13   5.2   2.8
 10250   4.2  39.6  255  25 13   2.5   1.4 |   4.1  39.4  255  25 13   3.2   1.8
 10000   4.3  39.7  255  25 13   3.4   1.9 |   4.3  39.7  250  24 12   3.8   2.1
  9750   4.7  40.5  250  24 12   5.4   3.0 |   4.7  40.5  250  23 12   5.8   3.2
  9500   5.0  41.0  250  23 12   4.7   2.6 |   5.1  41.2  245  22 11   5.2   2.9
  9250   5.3  41.5  250  22 11   2.8   1.5 |   5.4  41.7  245  21 11   3.2   1.8
  9000   5.5  41.9  245  21 11   2.7   1.5 |   5.5  41.9  245  20 10   2.4   1.3
  8750   5.7  42.3  245  19 10   4.2   2.3 |   5.8  42.4  240  19 10   3.5   1.9
  8500   6.0  42.8  240  17  9   3.2   1.7 |   6.0  42.8  240  17  9   2.6   1.5
  8250   6.2  43.2  235  15  8   1.9   1.0 |   6.1  43.0  235  15  8   1.0   0.6
  8000   6.3  43.3  230  13  7   2.0   1.1 |   6.1  43.0  225  13  7   1.3   0.7
  7750   6.5  43.7  220  12  6   3.2   1.7 |   6.3  43.3  220  12  6   2.9   1.6
  7500   6.7  44.1  210  11  6   2.5   1.4 |   6.5  43.7  215  11  6   2.6   1.4
  7250   6.8  44.2  205  12  6   1.5   0.8 |   6.6  43.9  210  11  5   2.2   1.2
  7000   6.9  44.4  195  12  6   2.3   1.3 |   6.8  44.2  205  10  5   2.0   1.1
  6750   7.1  44.8  190  13  7  -0.5  -0.3 |   6.9  44.4  195  10  5   2.5   1.4
  6500   6.8  44.2  185  12  6  -5.0  -2.8 |   7.2  45.0  195   9  5   4.8   2.6
  6250   6.3  43.3  180  12  6  -9.8  -5.4 |   7.6  45.7  190   8  4   6.1   3.3
  6000   5.8  42.4  170  11  6   2.5   1.4 |   8.0  46.4  185   7  4   4.8   2.7
  5750   6.0  42.8  150   8  4  -9.4  -5.2 |   8.3  46.9  185   6  3   7.0   3.8
  5500   4.0  39.2  140   7  4 -35.0 -19.2 |   9.0  48.2  185   6  3  10.1   5.5
  5250   1.9  35.4  125   6  3 -14.6  -8.0 |   9.7  49.5  185   5  3   7.7   4.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           11/28/2014 at 1400 MST          |       11/28/2014 at 1700 MST
                                           |
K index... -8.8  LI... +8.2                | K index... -11.0  LI... +8.9
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.9
                                           |
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 -69.6 -93.3  275  54 28   3.6   2.0 | -70.3 -94.5  270  52 27   3.5   1.9
 45000 -64.3 -83.7  280  69 36   3.0   1.6 | -64.8 -84.6  280  68 35   3.4   1.9
 40000 -59.9 -75.8  280  84 43   2.8   1.5 | -59.8 -75.6  275  85 44   3.2   1.8
 38000 -55.9 -68.6  280  82 42   7.5   4.1 | -55.6 -68.1  275  83 43   7.9   4.3
 36000 -51.4 -60.5  280  78 40   7.5   4.1 | -50.8 -59.4  270  80 41   7.9   4.3
 34000 -46.8 -52.2  275  74 38   7.5   4.1 | -46.3 -51.3  270  76 39   7.2   3.9
 32000 -41.8 -43.2  275  70 36   7.5   4.1 | -42.0 -43.6  270  74 38   7.2   3.9
 30000 -37.2 -35.0  270  67 34   7.7   4.2 | -37.1 -34.8  270  71 36   7.3   4.0
 29000 -34.9 -30.8  270  66 34   7.7   4.2 | -34.9 -30.8  270  70 36   7.3   4.0
 28000 -32.6 -26.7  270  64 33   7.7   4.2 | -32.7 -26.9  270  68 35   7.3   4.0
 27000 -30.3 -22.5  270  63 32   7.5   4.1 | -30.5 -22.9  270  67 34   7.7   4.2
 26000 -28.1 -18.6  270  61 32   7.5   4.1 | -28.2 -18.8  270  66 34   7.7   4.2
 25000 -25.8 -14.4  270  60 31   7.5   4.1 | -25.9 -14.6  270  64 33   7.7   4.2
 24000 -23.6 -10.5  270  59 30   7.3   4.0 | -23.6 -10.5  270  63 32   7.4   4.1
 23000 -21.4  -6.5  265  59 30   7.3   4.0 | -21.3  -6.3  270  62 32   7.4   4.1
 22000 -19.2  -2.6  265  58 30   7.3   4.0 | -19.1  -2.4  265  60 31   7.4   4.1
 21000 -16.9   1.6  265  58 30   7.9   4.4 | -16.9   1.6  265  59 30   7.6   4.1
 20000 -14.5   5.9  265  57 30   7.9   4.4 | -14.6   5.7  265  57 29   7.6   4.1
 19500 -13.3   8.1  265  57 29   7.9   4.4 | -13.4   7.9  265  56 29   7.6   4.2
 19000 -12.1  10.2  265  57 29   8.2   4.5 | -12.3   9.9  265  55 28   7.7   4.2
 18500 -11.1  12.0  265  56 29   5.6   3.1 | -11.3  11.7  265  54 28   5.7   3.1
 18000 -10.2  13.6  265  55 28   5.8   3.2 | -10.4  13.3  265  53 27   5.7   3.1
 17500  -9.4  15.1  265  53 27   5.3   2.9 |  -9.6  14.7  265  52 27   5.5   3.0
 17000  -8.6  16.5  265  52 27   4.9   2.7 |  -8.8  16.2  265  50 26   5.0   2.7
 16500  -7.9  17.8  265  50 26   4.9   2.7 |  -8.1  17.4  265  49 25   5.1   2.8
 16000  -7.3  18.9  265  48 25   4.0   2.2 |  -7.4  18.7  265  47 24   4.1   2.2
 15500  -6.4  20.5  265  45 23   4.5   2.5 |  -6.8  19.8  265  45 23   4.2   2.3
 15000  -5.6  21.9  265  43 22   5.5   3.0 |  -5.8  21.6  265  43 22   5.0   2.7
 14500  -4.8  23.4  265  40 21   5.5   3.0 |  -5.1  22.8  265  41 21   4.9   2.7
 14000  -3.9  25.0  260  38 20   6.8   3.7 |  -4.3  24.3  265  40 20   6.0   3.3
 13500  -2.9  26.8  260  36 19   6.5   3.6 |  -3.4  25.9  265  38 20   5.9   3.2
 13000  -1.8  28.8  260  35 18   8.1   4.4 |  -2.5  27.5  265  37 19   7.1   3.9
 12500  -0.6  30.9  260  33 17   8.1   4.4 |  -1.4  29.5  265  36 18   7.2   3.9
 12000   0.6  33.1  260  31 16   7.4   4.0 |  -0.4  31.3  265  35 18   7.4   4.0
 11500   1.7  35.1  260  30 15   7.4   4.1 |   0.8  33.4  260  33 17   7.5   4.1
 11000   2.7  36.9  255  28 14   5.9   3.2 |   1.8  35.2  260  32 16   5.4   2.9
 10500   3.5  38.3  250  26 14   6.2   3.4 |   2.5  36.5  260  30 15   4.5   2.5
 10250   4.0  39.2  250  26 13   4.0   2.2 |   2.9  37.2  255  29 15   6.5   3.6
 10000   4.2  39.6  250  25 13   3.8   2.1 |   3.5  38.3  255  27 14   7.1   3.9
  9750   4.6  40.3  245  24 12   5.7   3.1 |   3.9  39.0  250  25 13   5.5   3.0
  9500   4.9  40.8  245  23 12   5.6   3.1 |   4.3  39.7  250  23 12   6.2   3.4
  9250   5.3  41.5  240  22 11   4.2   2.3 |   4.7  40.5  245  22 11   5.3   2.9
  9000   5.5  41.9  240  21 11   2.4   1.3 |   5.0  41.0  240  20 10   4.7   2.6
  8750   5.7  42.3  235  19 10   2.8   1.5 |   5.4  41.7  235  18  9   5.1   2.8
  8500   5.8  42.4  230  17  9   2.7   1.5 |   5.7  42.3  230  17  9   5.1   2.8
  8250   6.0  42.8  225  15  8   2.7   1.5 |   6.0  42.8  225  16  8   5.0   2.8
  8000   6.2  43.2  220  13  7   3.1   1.7 |   6.4  43.5  220  15  8   5.3   2.9
  7750   6.4  43.5  210  11  6   3.3   1.8 |   6.8  44.2  210  14  7   5.7   3.1
  7500   6.6  43.9  200   9  5   4.5   2.5 |   7.2  45.0  205  14  7   5.8   3.2
  7250   7.0  44.6  200   8  4   6.2   3.4 |   7.6  45.7  200  13  7   6.2   3.4
  7000   7.5  45.5  200   7  4   6.9   3.8 |   8.1  46.6  195  13  6   6.2   3.4
  6750   8.0  46.4  200   7  3   8.5   4.6 |   8.5  47.3  190  12  6   6.0   3.3
  6500   8.7  47.7  200   6  3  10.0   5.5 |   9.0  48.2  185  11  6   5.5   3.0
  6250   9.5  49.1  205   6  3  10.7   5.9 |   9.3  48.7  185  10  5   4.4   2.4
  6000  10.3  50.5  205   5  3  10.1   5.5 |   9.7  49.5  185   9  4   6.3   3.4
  5750  11.0  51.8  205   5  3   8.9   4.9 |  10.1  50.2  180   7  3   3.3   1.8
  5500  11.6  52.9  210   5  2   8.5   4.6 |  10.0  50.0  175   5  2  -5.1  -2.8
  5250  12.3  54.1  210   5  2   9.0   4.9 |   9.5  49.1  170   4  2  -7.3  -4.0
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  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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