Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 111222
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0622 MDT Thursday, September 11, 2014

This forecast is for Thursday, September 11, 2014:

If the trigger temperature of 73.8 F/23.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 854 ft/min (4.3 m/s)
   Maximum height of thermals.................. 14846 ft MSL (10007 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1115 MDT
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................. 11106 ft MSL (6267 ft AGL)
Thermal soaring outlook for Friday 09/12....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:51:52 / 19:30:20 MDT
Total possible sunshine........... 12 hr 38 min 28 sec (758 min 28 sec)
Altitude of sun at 13:10:37 MDT... 55.25 degrees

Upper air data from rawinsonde observation taken on 09/11/2014 at 0600 MDT

Freezing level.................. 13640 ft MSL (8801 ft AGL)
Convective condensation level... 14564 ft MSL (9725 ft AGL)
Lifted condensation level....... 14844 ft MSL (10005 ft AGL)
Lifted index.................... +2.0
K index......................... +14.1

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  -65.7 -86.3   280   57   29   5.6   3.1   85.8 186.4    33.5      M    M
 45000  -57.8 -72.0   275   71   37   7.0   3.8   74.5 166.1    29.0      M    M
 40000  -54.4 -65.9   260   57   29  -1.0  -0.6   57.1 134.8    19.4      M    M
 38000  -51.4 -60.5   260   54   28   3.0   1.7   52.7 126.9    17.0      M    M
 36000  -47.4 -53.3   255   51   26   7.7   4.2   49.0 120.2    14.9      M    M
 34000  -43.1 -45.6   260   45   23   8.4   4.6   46.8 116.2    13.7      M    M
 32000  -37.6 -35.7   265   39   20   9.1   5.0   46.3 115.3    13.6      M    M
 30000  -32.5 -26.5   270   38   20   8.1   4.4   45.3 113.6    13.3      M    M
 29000  -30.1 -22.2   275   37   19   8.1   4.4   44.5 112.1    12.8      M    M
 28000  -27.7 -17.9   275   37   19   8.1   4.4   43.8 110.9    12.4      M    M
 27000  -25.3 -13.5   280   36   19   8.1   4.4   43.3 109.9    12.1      M    M
 26000  -22.8  -9.0   285   36   19   8.1   4.4   42.8 109.0    11.9      M    M
 25000  -20.4  -4.7   285   35   18   8.1   4.4   42.1 107.8    11.5      M    M
 24000  -18.1  -0.6   285   35   18   7.6   4.2   41.3 106.4    11.0      M    M
 23000  -16.0   3.2   285   37   19   5.4   3.0   40.2 104.4    10.2      M    M
 22000  -14.4   6.1   285   39   20   5.5   3.0   38.7 101.7     9.1      M    M
 21000  -12.7   9.1   285   35   18   5.8   3.2   37.2  98.9     7.9      M    M
 20000  -11.5  11.3   280   31   16   3.3   1.8   35.2  95.3     6.2      M    M
 19500  -10.5  13.1   280   31   16  10.0   5.5   34.6  94.3     5.8      M    M
 19000   -8.5  16.7   280   31   16   7.9   4.3   34.4  94.0     5.7      M    M
 18500   -7.4  18.7   280   30   15   4.0   2.2   34.0  93.1     5.3      M    M
 18000   -7.1  19.2   280   29   15   4.4   2.4   32.7  90.8     4.1      M    M
 17500   -6.0  21.2   275   28   15   8.1   4.5   32.2  90.0     3.8      M    M
 17000   -4.8  23.4   275   27   14   7.4   4.1   32.0  89.5     3.6      M    M
 16500   -4.1  24.6   275   27   14   3.7   2.0   31.2  88.1     2.9      M    M
 16000   -3.5  25.7   275   26   13   4.0   2.2   30.2  86.4     2.0      M    M
 15500   -3.0  26.6   270   23   12   4.1   2.3   29.2  84.6     1.0      M    M
 15000   -2.4  27.7   265   21   11   4.5   2.5   28.3  82.9     0.1      M    M
 14500   -1.7  28.9   275   18    9   5.7   3.1   27.6  81.6    -0.5    823  4.2
 14000   -0.7  30.7   290   16    8   7.4   4.1   27.0  80.6    -1.1    780  4.0
 13500    0.4  32.7   300   18    9   7.5   4.1   26.6  80.0    -1.4    731  3.7
 13000    1.5  34.7   305   20   10   7.5   4.1   26.3  79.3    -1.8    683  3.5
 12500    2.6  36.7   300   15    8   7.5   4.1   25.9  78.6    -2.1    635  3.2
 12000    3.8  38.8   290   11    6   7.8   4.3   25.5  78.0    -2.5    586  3.0
 11500    4.9  40.8   285   12    6   8.8   4.8   25.3  77.6    -2.8    536  2.7
 11000    6.2  43.2   280   13    7   8.9   4.9   25.2  77.3    -3.1    485  2.5
 10500    7.4  45.3   275   15    7   9.0   4.9   25.1  77.1    -3.3    433  2.2
 10250    8.0  46.4   275   15    8   8.2   4.5   25.0  77.0    -3.5    408  2.1
 10000    8.5  47.3   270   15    8   7.8   4.3   24.8  76.7    -3.7    385  2.0
  9750    9.0  48.2   270   15    8   8.0   4.4   24.7  76.4    -3.9    361  1.8
  9500    9.6  49.3   265   15    8   8.1   4.4   24.5  76.2    -4.0    337  1.7
  9250   10.2  50.4   265   15    8   8.1   4.5   24.4  76.0    -4.1    311  1.6
  9000   10.8  51.4   260   15    8   8.1   4.5   24.3  75.7    -4.3    285  1.4
  8750   11.5  52.7   260   13    7   8.1   4.5   24.2  75.5    -4.4    259  1.3
  8500   12.1  53.8   255   10    5   8.1   4.5   24.0  75.3    -4.5    233  1.2
  8250   12.7  54.9   250    8    4   8.1   4.5   23.9  75.1    -4.6    207  1.1
  8000   13.3  55.9   240    5    3   8.1   4.4   23.8  74.8    -4.8    182  0.9
  7750   13.9  57.0   215    5    3   8.3   4.6   23.7  74.6    -4.9    156  0.8
  7500   14.5  58.1   200    6    3   7.4   4.1   23.5  74.4    -5.0    130  0.7
  7250   15.0  59.0   185    7    4   5.1   2.8   23.3  73.9    -5.3    109  0.6
  7000   15.3  59.5   175    9    4   4.9   2.7   22.9  73.2    -5.8     92  0.5
  6750   15.6  60.1   160   11    6   3.6   1.9   22.5  72.5    -6.2     75  0.4
  6500   15.6  60.1   150   14    7  -2.6  -1.4   21.8  71.3    -6.9     67  0.3
  6250   15.2  59.4   145   17    9  -5.1  -2.8   20.7  69.3    -8.1     72  0.4
  6000   14.8  58.6   140   21   11  -5.4  -3.0   19.6  67.3    -9.2     77  0.4
  5750   14.4  57.9   140   20   10  -1.5  -0.8   18.5  65.3   -10.4     82  0.4
  5500   14.6  58.3   135   17    9   3.8   2.1   17.9  64.3   -11.0     70  0.4
  5250   14.8  58.6   130   14    7   0.5   0.3   17.4  63.3   -11.5     57  0.3
  5000   14.4  57.9   120   12    6  -9.4  -5.1   16.4  61.5   -12.7     60  0.3

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

           09/11/2014 at 0900 MDT          |       09/11/2014 at 1200 MDT
                                           |
K index... +14.2  LI... +1.0               | K index... +14.5  LI... +0.1
CAPE... 0.0  CIN... -0.7                   | CAPE... +0.8  CIN... -0.1
                                           |
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 -65.6 -86.1  280  57 29   4.4   2.4 | -65.4 -85.7  280  56 29   3.9   2.2
 45000 -58.7 -73.7  280  62 32   4.5   2.5 | -58.8 -73.8  275  63 32   5.6   3.1
 40000 -51.9 -61.4  270  56 29   3.8   2.1 | -50.5 -58.9  280  56 29   3.2   1.7
 38000 -49.6 -57.3  270  54 28   3.9   2.1 | -48.4 -55.1  275  54 28   3.4   1.9
 36000 -47.2 -53.0  265  51 26   4.0   2.2 | -46.4 -51.5  270  53 27   3.5   1.9
 34000 -43.3 -45.9  270  49 25   7.7   4.2 | -43.0 -45.4  265  52 27   6.6   3.6
 32000 -38.1 -36.6  270  45 23   7.7   4.2 | -38.5 -37.3  265  50 26   6.7   3.7
 30000 -33.1 -27.6  270  43 22   8.6   4.7 | -33.6 -28.5  270  48 25   8.6   4.7
 29000 -30.5 -22.9  275  42 22   8.6   4.7 | -31.1 -24.0  270  48 24   8.6   4.7
 28000 -27.9 -18.2  275  41 21   8.4   4.6 | -28.5 -19.3  270  47 24   8.3   4.6
 27000 -25.5 -13.9  275  41 21   8.0   4.4 | -26.2 -15.2  275  45 23   7.6   4.2
 26000 -23.1  -9.6  280  40 21   8.0   4.4 | -23.9 -11.0  275  44 23   7.6   4.2
 25000 -20.7  -5.3  280  39 20   8.2   4.5 | -21.6  -6.9  280  43 22   7.6   4.2
 24000 -18.6  -1.5  280  39 20   6.4   3.5 | -19.5  -3.1  280  42 21   7.0   3.8
 23000 -16.7   1.9  285  38 20   6.4   3.5 | -17.4   0.7  280  40 21   7.0   3.8
 22000 -14.8   5.4  285  37 19   6.4   3.5 | -15.3   4.5  280  38 20   7.2   3.9
 21000 -13.0   8.6  285  36 18   5.7   3.2 | -13.5   7.7  280  37 19   5.6   3.1
 20000 -11.3  11.7  285  34 18   5.8   3.2 | -11.8  10.8  280  36 18   5.6   3.1
 19500 -10.5  13.1  285  34 17   5.8   3.2 | -11.0  12.2  280  35 18   5.7   3.1
 19000  -9.6  14.7  285  33 17   6.0   3.3 | -10.2  13.6  280  34 18   5.9   3.2
 18500  -8.7  16.3  285  32 16   6.2   3.4 |  -9.3  15.3  280  33 17   6.0   3.3
 18000  -7.8  18.0  285  31 16   6.2   3.4 |  -8.4  16.9  280  32 17   6.0   3.3
 17500  -6.9  19.6  285  30 15   5.6   3.1 |  -7.5  18.5  280  31 16   5.8   3.2
 17000  -6.1  21.0  280  29 15   5.7   3.1 |  -6.7  19.9  275  30 16   5.8   3.2
 16500  -5.2  22.6  280  28 14   5.1   2.8 |  -5.8  21.6  275  29 15   6.2   3.4
 16000  -4.5  23.9  280  26 14   5.0   2.7 |  -4.9  23.2  275  28 14   6.4   3.5
 15500  -3.8  25.2  280  25 13   5.2   2.9 |  -4.0  24.8  275  27 14   6.6   3.6
 15000  -2.6  27.3  275  24 12   5.8   3.2 |  -2.4  27.7  275  25 13   7.1   3.9
 14500  -1.7  28.9  275  23 12   7.2   3.9 |  -1.3  29.7  270  24 13   7.5   4.1
 14000  -0.6  30.9  270  22 12   8.0   4.4 |  -0.2  31.6  270  24 12   7.8   4.3
 13500   0.6  33.1  270  22 11   8.5   4.7 |   0.9  33.6  270  24 12   8.2   4.5
 13000   1.8  35.2  265  22 11   9.1   5.0 |   2.2  36.0  265  23 12   8.8   4.8
 12500   3.1  37.6  265  21 11   9.2   5.0 |   3.5  38.3  265  23 12   8.9   4.9
 12000   4.4  39.9  260  21 11   9.1   5.0 |   4.8  40.6  260  23 12   9.2   5.0
 11500   5.7  42.3  255  20 10   9.2   5.0 |   6.1  43.0  260  23 12   9.2   5.1
 11000   7.0  44.6  255  19 10   9.0   4.9 |   7.4  45.3  255  22 11   8.9   4.9
 10500   8.3  46.9  255  18  9   5.2   2.8 |   8.7  47.7  255  21 11   4.9   2.7
 10250   8.6  47.5  255  18  9   5.6   3.1 |   8.9  48.0  255  21 11   5.7   3.1
 10000   9.3  48.7  255  17  9  10.9   6.0 |   9.6  49.3  255  20 10  11.7   6.4
  9750  10.0  50.0  255  16  8  10.0   5.5 |  10.4  50.7  255  19 10  10.7   5.9
  9500  10.7  51.3  255  16  8   8.5   4.7 |  11.1  52.0  255  19 10   9.1   5.0
  9250  11.2  52.2  255  15  8   5.7   3.1 |  11.6  52.9  255  18  9   6.5   3.5
  9000  11.6  52.9  255  14  7   6.5   3.5 |  12.1  53.8  250  16  8   7.4   4.0
  8750  12.1  53.8  255  12  6   7.5   4.1 |  12.6  54.7  250  15  8   8.3   4.5
  8500  12.7  54.9  250  11  6   6.0   3.3 |  13.2  55.8  250  13  7   6.7   3.7
  8250  13.0  55.4  245  10  5   4.5   2.5 |  13.6  56.5  245  11  6   5.0   2.7
  8000  13.4  56.1  240   8  4   5.1   2.8 |  14.0  57.2  245   9  5   5.6   3.1
  7750  13.8  56.8  230   7  4   5.5   3.0 |  14.4  57.9  240   7  4   6.0   3.3
  7500  14.2  57.6  215   6  3   4.3   2.3 |  14.9  58.8  235   6  3   7.9   4.3
  7250  14.5  58.1  200   7  4   3.3   1.8 |  15.6  60.1  235   6  3   9.0   4.9
  7000  14.8  58.6  190   8  4   4.2   2.3 |  16.3  61.3  235   6  3   9.6   5.3
  6750  15.1  59.2  180   9  5   3.2   1.8 |  17.0  62.6  235   5  3  10.9   6.0
  6500  15.2  59.4  175  10  5   0.5   0.3 |  17.8  64.0  235   5  3  10.6   5.8
  6250  15.2  59.4  170   9  5   0.2   0.1 |  18.6  65.5  235   5  3  10.6   5.8
  6000  15.2  59.4  165   9  4  -0.2  -0.1 |  19.4  66.9  235   5  3   9.9   5.5
  5750  15.2  59.4  155   7  4   2.7   1.5 |  20.1  68.2  235   5  2  11.5   6.3
  5500  15.6  60.1  150   6  3   5.9   3.2 |  21.1  70.0  240   5  3  13.8   7.6
  5250  15.9  60.6  150   6  3   3.4   1.9 |  22.1  71.8  240   5  3  12.0   6.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/11/2014 at 1500 MDT          |       09/11/2014 at 1800 MDT
                                           |
K index... +9.7  LI... -0.0                | K index... +18.3  LI... +1.1
CAPE... 0.0  CIN... -14.8                  | 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 -64.9 -84.8  275  48 25   3.5   1.9 | -64.7 -84.5  280  46 24   3.6   2.0
 45000 -58.8 -73.8  275  63 33   5.5   3.0 | -58.6 -73.5  280  63 33   5.3   2.9
 40000 -50.6 -59.1  275  59 30   4.0   2.2 | -50.8 -59.4  280  62 32   4.1   2.2
 38000 -48.2 -54.8  275  56 29   4.1   2.2 | -48.3 -54.9  285  61 31   4.1   2.3
 36000 -45.7 -50.3  275  54 28   4.1   2.3 | -45.8 -50.4  290  60 31   4.2   2.3
 34000 -42.5 -44.5  275  53 27   6.0   3.3 | -42.4 -44.3  290  58 30   6.4   3.5
 32000 -38.4 -37.1  275  52 27   6.1   3.3 | -38.1 -36.6  290  55 28   6.4   3.5
 30000 -34.0 -29.2  275  51 26   7.7   4.2 | -33.9 -29.0  285  52 27   7.3   4.0
 29000 -31.7 -25.1  280  50 26   7.7   4.2 | -31.7 -25.1  285  51 26   7.3   4.0
 28000 -29.4 -20.9  280  49 25   7.7   4.2 | -29.5 -21.1  285  50 26   7.3   4.0
 27000 -27.1 -16.8  280  48 24   7.8   4.3 | -27.3 -17.1  285  48 25   7.4   4.1
 26000 -24.7 -12.5  280  46 24   7.8   4.3 | -25.1 -13.2  285  47 24   7.4   4.1
 25000 -22.4  -8.3  280  44 23   7.8   4.3 | -22.9  -9.2  285  46 23   7.4   4.1
 24000 -20.3  -4.5  280  43 22   6.9   3.8 | -20.7  -5.3  285  44 23   7.3   4.0
 23000 -18.2  -0.8  280  41 21   6.9   3.8 | -18.5  -1.3  285  43 22   7.3   4.0
 22000 -16.1   3.0  280  40 21   7.0   3.8 | -16.3   2.7  285  42 21   7.4   4.1
 21000 -14.2   6.4  280  39 20   6.4   3.5 | -14.3   6.3  285  40 21   6.6   3.6
 20000 -12.3   9.9  280  37 19   6.4   3.5 | -12.3   9.9  285  39 20   6.6   3.6
 19500 -11.3  11.7  280  37 19   6.4   3.5 | -11.4  11.5  285  38 19   6.6   3.6
 19000 -10.3  13.5  280  36 19   6.2   3.4 | -10.4  13.3  285  37 19   6.2   3.4
 18500  -9.4  15.1  280  35 18   6.1   3.4 |  -9.5  14.9  285  36 18   6.0   3.3
 18000  -8.5  16.7  275  34 18   6.2   3.4 |  -8.6  16.5  285  34 18   6.0   3.3
 17500  -7.6  18.3  275  33 17   7.2   3.9 |  -7.7  18.1  285  33 17   6.9   3.8
 17000  -6.5  20.3  275  32 17   7.1   3.9 |  -6.7  19.9  285  31 16   6.8   3.7
 16500  -5.5  22.1  275  31 16   7.4   4.1 |  -5.7  21.7  285  30 15   7.8   4.3
 16000  -4.3  24.3  275  30 16   7.5   4.1 |  -4.5  23.9  285  28 14   8.1   4.5
 15500  -3.2  26.2  275  29 15   7.7   4.2 |  -3.3  26.1  285  26 13   8.3   4.5
 15000  -1.4  29.5  270  28 14   8.1   4.4 |  -1.5  29.3  285  24 12   8.4   4.6
 14500  -0.3  31.5  265  27 14   8.3   4.5 |  -0.3  31.5  280  23 12   8.7   4.8
 14000   1.0  33.8  265  26 13   8.4   4.6 |   1.0  33.8  280  22 11   8.9   4.9
 13500   2.2  36.0  260  26 13   8.5   4.7 |   2.3  36.1  280  21 11   8.9   4.9
 13000   3.5  38.3  260  25 13   8.7   4.7 |   3.6  38.5  280  21 11   9.0   4.9
 12500   4.8  40.6  260  25 13   8.7   4.7 |   4.9  40.8  275  21 11   9.0   5.0
 12000   6.0  42.8  260  24 13   8.6   4.7 |   6.3  43.3  275  21 11   9.2   5.0
 11500   7.3  45.1  255  24 12   8.6   4.7 |   7.7  45.9  275  22 11   9.1   5.0
 11000   8.5  47.3  260  23 12   8.3   4.6 |   9.0  48.2  275  22 11   8.8   4.8
 10500   9.8  49.6  260  23 12   5.0   2.7 |  10.4  50.7  270  22 11   6.4   3.5
 10250  10.0  50.0  260  22 11   6.3   3.5 |  10.8  51.4  270  22 11   7.2   4.0
 10000  10.8  51.4  260  22 11  11.8   6.5 |  11.5  52.7  270  22 11  11.0   6.0
  9750  11.6  52.9  260  21 11  10.8   5.9 |  12.3  54.1  270  22 11  10.3   5.7
  9500  12.3  54.1  260  21 11   9.3   5.1 |  13.1  55.6  270  22 11   9.3   5.1
  9250  12.9  55.2  260  20 10   7.2   3.9 |  13.7  56.7  270  22 11   7.7   4.2
  9000  13.5  56.3  260  18  9   8.5   4.7 |  14.3  57.7  270  21 11   8.5   4.7
  8750  14.1  57.4  260  17  9   9.0   4.9 |  14.9  58.8  270  20 11   8.9   4.9
  8500  14.7  58.5  265  15  8   9.1   5.0 |  15.6  60.1  270  20 10   8.9   4.9
  8250  15.4  59.7  265  14  7   9.4   5.1 |  16.3  61.3  270  18  9   9.0   5.0
  8000  16.0  60.8  265  13  7   9.5   5.2 |  16.9  62.4  270  17  9   8.5   4.7
  7750  16.7  62.1  265  13  7   9.6   5.3 |  17.5  63.5  270  16  8   7.8   4.3
  7500  17.4  63.3  265  12  6   9.8   5.4 |  18.1  64.6  270  15  8   9.0   4.9
  7250  18.1  64.6  265  12  6  10.0   5.5 |  18.8  65.8  270  14  7  10.0   5.5
  7000  18.9  66.0  265  12  6   9.8   5.4 |  19.5  67.1  270  14  7   9.4   5.2
  6750  19.6  67.3  265  12  6   9.9   5.5 |  20.2  68.4  270  13  7   9.4   5.1
  6500  20.4  68.7  270  11  6  10.7   5.8 |  21.0  69.8  270  13  7  10.2   5.6
  6250  21.2  70.2  270  11  6  11.2   6.2 |  21.7  71.1  270  12  6  10.8   5.9
  6000  22.0  71.6  270  11  6  10.1   5.5 |  22.5  72.5  275  12  6  10.0   5.5
  5750  22.7  72.9  270  10  5  11.8   6.5 |  23.2  73.8  275  11  6   8.0   4.4
  5500  23.7  74.7  270  10  5  14.6   8.0 |  23.7  74.7  275  11  5   7.1   3.9
  5250  24.7  76.5  270  10  5  12.6   6.9 |  24.3  75.7  275  10  5   7.7   4.2
  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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