Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 101238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0537 MST Saturday, December 10, 2016

This forecast is for Saturday, December 10, 2016:

If the trigger temperature of 52.6 F/11.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6745 ft MSL (1906 ft AGL)

Forecast maximum temperature................... 44.0 F/7.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1100 AM MST
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6251 ft MSL (1412 ft AGL)
Thermal soaring outlook for Sunday 12/11....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:22:51 / 16:51:43 MST
Total possible sunshine........... 9 hr 28 min 52 sec (568 min 52 sec)
Altitude of sun at 12:07:20 MST... 27.95 degrees

Upper air data from rawinsonde observation taken on 12/10/2016 at 0500 MST

Freezing level.................. 6608 ft MSL (1769 ft AGL)
Additional freezing level....... 8535 ft MSL (3696 ft AGL)
Convective condensation level... 16556 ft MSL (11717 ft AGL)
Lifted condensation level....... 10174 ft MSL (5335 ft AGL)
Lifted index.................... +15.1
K index......................... -1.2

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -61.7 -79.1   285   57   29   1.0   0.5   99.8 211.7    52.8      M    M
 45000  -62.3 -80.1   290   71   37 -10.3  -5.7   74.1 165.4    41.0      M    M
 40000  -65.4 -85.7   300   75   39   4.5   2.5   45.8 114.4    25.5      M    M
 38000  -64.9 -84.8   310   89   46   2.6   1.5   37.7  99.8    20.8      M    M
 36000  -60.3 -76.5   300   72   37   8.5   4.7   35.9  96.6    20.2      M    M
 34000  -54.2 -65.6   295   70   36   9.6   5.3   35.2  95.4    20.3      M    M
 32000  -48.5 -55.3   290   69   36   9.1   5.0   34.9  94.9    20.6      M    M
 30000  -43.1 -45.6   285   71   37   9.5   5.2   34.4  94.0    20.8      M    M
 29000  -40.2 -40.4   285   69   36   9.5   5.2   34.2  93.6    20.9      M    M
 28000  -37.4 -35.3   285   68   35   9.5   5.2   34.1  93.4    21.1      M    M
 27000  -34.7 -30.5   285   66   34   8.7   4.8   33.9  92.9    21.1      M    M
 26000  -32.1 -25.8   285   65   33   8.7   4.7   33.4  92.1    21.0      M    M
 25000  -29.5 -21.1   285   63   32   8.7   4.8   33.1  91.5    21.0      M    M
 24000  -26.9 -16.4   285   60   31   9.3   5.1   32.6  90.8    20.9      M    M
 23000  -24.4 -11.9   280   58   30   6.0   3.3   32.2  89.9    20.7      M    M
 22000  -22.2  -8.0   280   56   29   7.9   4.3   31.2  88.2    20.1      M    M
 21000  -21.1  -6.0   275   54   28   4.8   2.6   29.1  84.4    18.6      M    M
 20000  -19.0  -2.2   270   52   27   7.5   4.1   28.2  82.8    18.0      M    M
 19500  -17.8  -0.0   270   53   27   7.7   4.2   27.9  82.1    17.8      M    M
 19000  -16.7   1.9   265   53   27   7.8   4.3   27.5  81.5    17.6      M    M
 18500  -15.1   4.8   265   55   28   4.7   2.6   26.8  80.2    17.1      M    M
 18000  -14.5   5.9   265   55   29   3.0   1.6   25.7  78.2    16.4      M    M
 17500  -14.1   6.6   270   56   29   5.5   3.0   24.5  76.1    15.4      M    M
 17000  -13.0   8.6   270   57   29   7.4   4.1   24.2  75.5    15.1      M    M
 16500  -11.9  10.6   275   55   28   8.0   4.4   23.8  74.8    14.8      M    M
 16000  -10.7  12.7   275   54   28   8.1   4.5   23.5  74.3    14.6      M    M
 15500   -9.4  15.1   270   52   27   9.2   5.0   23.3  73.9    14.6      M    M
 15000   -8.3  17.1   270   50   26   4.5   2.5   22.9  73.1    14.3      M    M
 14500   -7.6  18.3   265   48   25   5.3   2.9   22.0  71.5    13.6      M    M
 14000   -6.7  19.9   260   47   24   4.4   2.4   21.4  70.5    13.2      M    M
 13500   -6.1  21.0   255   46   23   5.9   3.2   20.5  68.9    12.3      M    M
 13000   -5.2  22.6   255   44   23   6.8   3.7   19.9  67.9    11.9      M    M
 12500   -4.1  24.6   255   43   22   6.9   3.8   19.4  67.0    11.5      M    M
 12000   -3.1  26.4   250   42   22   6.9   3.8   19.0  66.2    11.1      M    M
 11500   -2.1  28.2   250   41   21   7.1   3.9   18.5  65.3    10.7      M    M
 11000   -1.4  29.5   250   40   21   4.8   2.7   17.8  64.0    10.1      M    M
 10500   -1.7  28.9   240   36   19  -5.4  -3.0   16.0  60.8     8.4      M    M
 10250   -1.8  28.8   240   35   18   1.1   0.6   15.1  59.2     7.5      M    M
 10000   -1.7  28.9   235   32   17   1.0   0.6   14.5  58.0     6.9      M    M
  9750   -1.7  28.9   230   28   15  -0.1  -0.0   13.7  56.7     6.2      M    M
  9500   -1.7  28.9   230   24   13   0.8   0.5   13.0  55.3     5.5      M    M
  9250   -1.5  29.3   225   21   11   5.0   2.7   12.4  54.3     4.9      M    M
  9000   -1.0  30.2   215   17    9   7.4   4.1   12.2  53.9     4.7      M    M
  8750   -0.5  31.1   210   17    9   6.8   3.7   12.0  53.5     4.5      M    M
  8500    0.0  32.0   205   17    9   6.9   3.8   11.7  53.1     4.3      M    M
  8250    0.5  32.9   195   17    9   7.0   3.8   11.5  52.7     4.1      M    M
  8000    1.0  33.8   190   17    9   6.8   3.7   11.3  52.3     3.9      M    M
  7750    1.5  34.7   190   16    8   7.5   4.1   11.1  51.9     3.7      M    M
  7500    2.1  35.8   190   15    8   4.9   2.7   10.9  51.5     3.5      M    M
  7250    2.0  35.6   185   13    7  -9.5  -5.2   10.0  50.0     2.7      M    M
  7000    1.2  34.2   185   12    6  -1.8  -1.0    8.5  47.2     1.2      M    M
  6750    1.4  34.5   175   10    5 -11.3  -6.2    7.8  46.1     0.6      M    M
  6500   -0.3  31.5   160    9    4 -17.3  -9.5    5.3  41.6    -1.8    187  1.0
  6250   -0.6  30.9   135    8    4   1.0   0.6    4.3  39.7    -2.8    188  1.0
  6000   -0.7  30.7   115    9    4  -1.9  -1.0    3.5  38.2    -3.6    183  0.9
  5750   -0.8  30.6   105    8    4  -0.8  -0.5    2.6  36.7    -4.4    178  0.9
  5500   -0.8  30.6   100    6    3  -2.1  -1.2    1.8  35.2    -5.3    173  0.9
  5250   -1.3  29.7   090    5    2 -13.4  -7.3    0.6  33.0    -6.5    180  0.9
  5000   -2.9  26.8   070    3    2 -27.5 -15.1   -1.8  28.8    -8.8    220  1.1

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

           12/10/2016 at 0800 MST          |       12/10/2016 at 1100 MST
                                           |
K index... +7.8  LI... +5.7                | K index... +4.8  LI... +6.0
CAPE... 0.0  CIN... -1.1                   | 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 -65.2 -85.4  285  63 32  -0.5  -0.3 | -65.4 -85.7  290  63 32   0.2   0.1
 45000 -65.9 -86.6  290  69 35  -0.8  -0.4 | -65.0 -85.0  290  69 36   0.1   0.1
 40000 -62.8 -81.0  310  80 41   2.1   1.2 | -63.3 -81.9  310  76 39   1.1   0.6
 38000 -60.9 -77.6  310  79 41   4.0   2.2 | -61.3 -78.3  305  72 37   5.1   2.8
 36000 -58.5 -73.3  305  73 37   4.0   2.2 | -58.3 -72.9  295  64 33   5.1   2.8
 34000 -55.3 -67.5  295  67 35   9.2   5.1 | -54.5 -66.1  285  60 31   9.5   5.2
 32000 -49.7 -57.5  295  60 31   9.3   5.1 | -48.8 -55.8  280  58 30   9.6   5.3
 30000 -44.1 -47.4  290  55 28   9.7   5.3 | -43.1 -45.6  275  56 29   9.1   5.0
 29000 -41.2 -42.2  290  55 28   9.7   5.3 | -40.4 -40.7  275  56 29   9.1   5.0
 28000 -38.4 -37.1  290  55 28   9.7   5.3 | -37.7 -35.9  275  56 29   9.1   5.0
 27000 -35.5 -31.9  290  54 28   8.8   4.8 | -34.3 -29.7  275  56 29   8.0   4.4
 26000 -32.5 -26.5  290  58 30   8.0   4.4 | -31.9 -25.4  275  57 29   8.2   4.5
 25000 -30.1 -22.2  290  60 31   8.0   4.4 | -29.5 -21.1  280  57 29   8.2   4.5
 24000 -27.7 -17.9  290  63 32   7.6   4.2 | -27.1 -16.8  280  57 29   7.3   4.0
 23000 -25.5 -13.9  290  61 31   7.4   4.1 | -25.0 -13.0  280  57 29   6.9   3.8
 22000 -23.3  -9.9  285  60 31   7.5   4.1 | -23.0  -9.4  280  56 29   6.9   3.8
 21000 -21.2  -6.2  285  58 30   6.4   3.5 | -20.9  -5.6  280  56 29   7.2   4.0
 20000 -19.2  -2.6  280  58 30   6.5   3.6 | -18.8  -1.8  275  57 29   7.2   3.9
 19500 -18.3  -0.9  280  57 30   6.6   3.6 | -17.7   0.1  275  57 29   7.2   4.0
 19000 -17.3   0.9  280  57 29   6.6   3.6 | -16.7   1.9  275  57 29   7.2   4.0
 18500 -16.4   2.5  280  57 29   4.9   2.7 | -15.6   3.9  275  57 29   6.5   3.6
 18000 -15.7   3.7  280  56 29   4.6   2.5 | -14.7   5.5  275  57 29   6.3   3.4
 17500 -15.1   4.8  275  56 29   4.9   2.7 | -13.8   7.2  270  57 29   6.2   3.4
 17000 -14.2   6.4  275  55 29   6.2   3.4 | -12.8   9.0  270  57 30   6.0   3.3
 16500 -13.3   8.1  275  55 28   6.1   3.3 | -11.9  10.6  270  57 30   6.0   3.3
 16000 -12.3   9.9  275  53 27   7.4   4.1 | -11.0  12.2  270  57 29   7.1   3.9
 15500 -11.2  11.8  275  52 27   7.3   4.0 |  -9.9  14.2  265  55 28   7.1   3.9
 15000 -10.0  14.0  275  50 26   8.3   4.5 |  -8.8  16.2  265  54 28   7.3   4.0
 14500  -8.7  16.3  275  48 25   8.6   4.7 |  -7.6  18.3  265  51 26   7.4   4.1
 14000  -7.4  18.7  275  45 23   8.3   4.6 |  -6.5  20.3  265  48 25   7.2   4.0
 13500  -6.2  20.8  275  43 22   7.9   4.3 |  -5.5  22.1  260  45 23   6.7   3.7
 13000  -4.5  23.9  275  38 20   7.1   3.9 |  -4.0  24.8  260  40 20   6.2   3.4
 12500  -3.4  25.9  275  36 18   7.1   3.9 |  -3.1  26.4  255  36 19   6.1   3.3
 12000  -2.5  27.5  270  33 17   5.1   2.8 |  -2.3  27.9  250  34 17   4.6   2.5
 11500  -1.8  28.8  270  30 15   4.8   2.6 |  -1.7  28.9  250  31 16   4.1   2.3
 11000  -1.2  29.8  265  27 14   2.5   1.4 |  -1.2  29.8  245  29 15   2.9   1.6
 10500  -1.0  30.2  260  25 13   2.2   1.2 |  -0.9  30.4  240  27 14   2.8   1.5
 10250  -0.9  30.4  255  24 12   1.4   0.8 |  -0.8  30.6  240  26 13   1.9   1.0
 10000  -0.8  30.6  250  23 12   2.4   1.3 |  -0.7  30.7  240  25 13   1.2   0.7
  9750  -0.6  30.9  250  23 12   3.8   2.1 |  -0.7  30.7  240  24 12   1.7   0.9
  9500  -0.4  31.3  245  22 11   3.9   2.1 |  -0.6  30.9  235  23 12   1.7   0.9
  9250  -0.2  31.6  245  21 11   2.8   1.5 |  -0.5  31.1  235  22 11   1.4   0.8
  9000  -0.1  31.8  240  20 10   1.7   0.9 |  -0.4  31.3  235  20 10   2.3   1.3
  8750   0.1  32.2  235  19 10   2.3   1.2 |  -0.2  31.6  230  19 10   3.7   2.0
  8500   0.3  32.5  230  17  9   2.2   1.2 |   0.1  32.2  230  18  9   3.7   2.0
  8250   0.4  32.7  225  15  8   2.1   1.1 |   0.4  32.7  225  17  9   3.5   1.9
  8000   0.6  33.1  220  14  7   2.1   1.1 |   0.6  33.1  220  16  8   3.1   1.7
  7750   0.8  33.4  210  13  7   2.2   1.2 |   0.9  33.6  220  16  8   2.8   1.5
  7500   1.0  33.8  205  13  6   2.6   1.4 |   1.1  34.0  215  15  8   2.4   1.3
  7250   1.2  34.2  200  13  7   3.1   1.7 |   1.2  34.2  210  15  8   2.0   1.1
  7000   1.4  34.5  190  14  7   3.1   1.7 |   1.4  34.5  205  14  7   1.8   1.0
  6750   1.6  34.9  185  14  7   1.4   0.8 |   1.5  34.7  200  13  7   1.3   0.7
  6500   1.6  34.9  180  14  7  -2.1  -1.1 |   1.6  34.9  195  12  6   2.3   1.2
  6250   1.3  34.3  175  14  7  -6.5  -3.6 |   1.8  35.2  195  11  5   3.3   1.8
  6000   1.0  33.8  170  13  7   3.4   1.9 |   2.1  35.8  190   9  5   3.4   1.8
  5750   1.4  34.5  155  10  5  -4.7  -2.6 |   2.4  36.3  190   7  4   5.6   3.1
  5500   0.0  32.0  150   8  4 -23.8 -13.1 |   2.8  37.0  190   6  3   7.0   3.8
  5250  -1.4  29.5  140   7  4  -8.9  -4.9 |   3.3  37.9  190   6  3   6.0   3.3
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/10/2016 at 1400 MST          |       12/10/2016 at 1700 MST
                                           |
K index... +18.3  LI... +1.8               | K index... +21.1  LI... +1.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.4
                                           |
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 -66.0 -86.8  295  68 35   0.9   0.5 | -65.5 -85.9  290  71 37   0.8   0.5
 45000 -64.6 -84.3  300  78 40   0.9   0.5 | -64.2 -83.6  295  79 41   0.9   0.5
 40000 -63.2 -81.8  300  74 38   0.9   0.5 | -63.9 -83.0  300  88 45   0.1   0.1
 38000 -60.8 -77.4  295  72 37   6.3   3.4 | -61.5 -78.7  300  90 46   7.0   3.8
 36000 -57.1 -70.8  285  73 37   6.3   3.4 | -57.3 -71.1  300  91 47   7.0   3.9
 34000 -53.0 -63.4  275  74 38   8.7   4.8 | -52.9 -63.2  300  88 46   8.7   4.8
 32000 -47.7 -53.9  275  69 35   8.8   4.8 | -47.7 -53.9  290  76 39   8.7   4.8
 30000 -42.5 -44.5  275  65 33   8.6   4.7 | -42.4 -44.3  285  68 35   8.8   4.8
 29000 -39.9 -39.8  275  64 33   8.7   4.8 | -39.8 -39.6  290  68 35   8.9   4.9
 28000 -37.3 -35.1  275  62 32   8.7   4.8 | -37.2 -35.0  290  69 35   8.9   4.9
 27000 -34.2 -29.6  275  61 31   7.0   3.9 | -34.5 -30.1  290  69 36   8.6   4.7
 26000 -32.1 -25.8  270  59 30   7.1   3.9 | -31.5 -24.7  285  69 36   8.2   4.5
 25000 -30.0 -22.0  270  57 30   7.1   3.9 | -29.0 -20.2  285  70 36   8.2   4.5
 24000 -27.8 -18.0  265  56 29   7.7   4.2 | -26.6 -15.9  280  70 36   8.0   4.4
 23000 -25.5 -13.9  265  54 28   8.1   4.4 | -24.3 -11.7  275  66 34   7.8   4.3
 22000 -23.1  -9.6  270  52 27   8.1   4.5 | -22.0  -7.6  270  63 32   7.9   4.3
 21000 -20.7  -5.3  270  51 26   7.2   4.0 | -19.8  -3.6  265  60 31   5.6   3.0
 20000 -18.6  -1.5  275  50 26   7.2   4.0 | -18.3  -0.9  265  58 30   5.2   2.8
 19500 -17.5   0.5  275  50 25   7.2   4.0 | -17.5   0.5  265  56 29   5.2   2.9
 19000 -16.5   2.3  280  49 25   7.2   4.0 | -16.7   1.9  270  55 28   5.2   2.9
 18500 -15.4   4.3  280  49 25   7.0   3.9 | -16.0   3.2  270  54 28   5.7   3.1
 18000 -14.4   6.1  280  49 25   6.9   3.8 | -15.1   4.8  265  52 27   6.2   3.4
 17500 -13.4   7.9  280  50 26   6.9   3.8 | -14.2   6.4  265  49 25   6.2   3.4
 17000 -12.4   9.7  280  50 26   6.5   3.6 | -13.2   8.2  265  47 24   6.9   3.8
 16500 -11.5  11.3  280  50 26   6.5   3.6 | -12.2  10.0  265  44 23   6.9   3.8
 16000 -10.5  13.1  280  50 26   6.3   3.5 | -11.3  11.7  270  42 21   5.6   3.1
 15500  -9.6  14.7  280  51 26   6.3   3.5 | -10.5  13.1  275  38 20   5.2   2.9
 15000  -8.7  16.3  280  51 26   6.1   3.3 |  -9.8  14.4  280  35 18   5.4   2.9
 14500  -7.9  17.8  280  51 26   5.8   3.2 |  -8.9  16.0  285  36 19   5.7   3.1
 14000  -7.0  19.4  280  51 26   5.8   3.2 |  -8.1  17.4  285  37 19   5.8   3.2
 13500  -6.2  20.8  275  50 26   6.1   3.4 |  -7.2  19.0  290  38 20   6.8   3.7
 13000  -4.8  23.4  275  50 26   5.9   3.2 |  -5.7  21.7  285  39 20   6.3   3.4
 12500  -4.0  24.8  275  50 26   5.7   3.1 |  -4.9  23.2  285  39 20   5.9   3.3
 12000  -3.2  26.2  270  50 26   3.9   2.1 |  -4.1  24.6  280  39 20   5.7   3.1
 11500  -2.9  26.8  270  47 24   2.5   1.4 |  -3.3  26.1  280  39 20   5.4   2.9
 11000  -2.5  27.5  265  44 22   0.9   0.5 |  -2.5  27.5  275  40 20   4.1   2.2
 10500  -2.5  27.5  260  38 20  -0.3  -0.1 |  -2.1  28.2  265  37 19   2.8   1.5
 10250  -2.5  27.5  255  35 18   0.3   0.2 |  -1.9  28.6  265  36 18   2.5   1.4
 10000  -2.2  28.0  255  33 17   6.1   3.4 |  -1.7  28.9  260  34 18   2.3   1.3
  9750  -1.6  29.1  250  31 16   9.5   5.2 |  -1.5  29.3  255  32 16   2.3   1.2
  9500  -0.9  30.4  250  30 15   8.8   4.8 |  -1.4  29.5  250  30 15   2.3   1.3
  9250  -0.2  31.6  245  28 15   8.3   4.5 |  -1.2  29.8  245  28 14   2.3   1.3
  9000   0.3  32.5  245  27 14   5.8   3.2 |  -0.9  30.4  245  26 13   5.1   2.8
  8750   0.7  33.3  240  26 13   4.8   2.6 |  -0.4  31.3  240  25 13   7.4   4.0
  8500   1.1  34.0  235  25 13   5.5   3.0 |   0.1  32.2  235  23 12   6.7   3.7
  8250   1.4  34.5  230  24 12   3.6   1.9 |   0.6  33.1  230  22 11   7.5   4.1
  8000   1.6  34.9  225  21 11   1.7   0.9 |   1.2  34.2  230  21 11   7.9   4.3
  7750   1.7  35.1  220  19 10   2.5   1.4 |   1.7  35.1  225  20 10   6.9   3.8
  7500   1.9  35.4  215  17  9   2.8   1.5 |   2.2  36.0  220  19 10   6.7   3.7
  7250   2.1  35.8  205  15  8   3.2   1.8 |   2.7  36.9  215  17  9   5.1   2.8
  7000   2.3  36.1  205  13  7   3.7   2.1 |   3.0  37.4  210  16  8   3.7   2.0
  6750   2.6  36.7  200  11  6   4.3   2.4 |   3.3  37.9  210  14  7   4.3   2.3
  6500   3.0  37.4  200   9  5   5.0   2.8 |   3.6  38.5  200  12  6   2.5   1.4
  6250   3.4  38.1  200   7  4   5.1   2.8 |   3.6  38.5  195  10  5   0.1   0.1
  6000   3.7  38.7  205   6  3   5.4   3.0 |   3.6  38.5  190   8  4   0.5   0.3
  5750   4.2  39.6  210   4  2   5.9   3.2 |   3.7  38.7  175   6  3  -0.6  -0.3
  5500   4.6  40.3  215   3  2   5.5   3.0 |   3.5  38.3  155   4  2  -4.5  -2.5
  5250   5.0  41.0  220   3  2   4.7   2.6 |   3.0  37.4  150   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 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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