Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 131226
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0626 MDT Saturday, September 13, 2014

This forecast is for Saturday, September 13, 2014:

If the trigger temperature of 77.2 F/25.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 595 ft/min (3.0 m/s)
   Maximum height of thermals.................. 12236 ft MSL (7397 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1245 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................. 8554 ft MSL (3714 ft AGL)
Thermal soaring outlook for Sunday 09/14....... Good

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

Remarks...

Sunrise/Sunset.................... 06:53:40 / 19:27:08 MDT
Total possible sunshine........... 12 hr 33 min 28 sec (753 min 28 sec)
Altitude of sun at 13:09:55 MDT... 54.49 degrees

Upper air data from rawinsonde observation taken on 09/13/2014 at 0600 MDT

Freezing level.................. 14391 ft MSL (9552 ft AGL)
Convective condensation level... 18451 ft MSL (13612 ft AGL)
Lifted condensation level....... 16801 ft MSL (11962 ft AGL)
Lifted index.................... +2.7
K index......................... -3.4

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -66.8 -88.2   275   46   24   3.9   2.1   85.3 185.5    33.1      M    M
 45000  -59.4 -74.9   280   55   28   6.8   3.7   72.0 161.6    27.4      M    M
 40000  -54.5 -66.1   265   56   29   2.4   1.3   56.9 134.3    19.3      M    M
 38000  -52.3 -62.1   265   51   26   4.3   2.4   51.4 124.5    16.1      M    M
 36000  -48.2 -54.8   265   47   24   8.8   4.9   48.9 120.0    14.7      M    M
 34000  -42.1 -43.8   265   44   23  10.3   5.6   49.1 120.4    15.3      M    M
 32000  -37.6 -35.7   270   42   22   9.5   5.2   46.4 115.5    13.7      M    M
 30000  -32.0 -25.6   270   42   22   8.2   4.5   46.0 114.8    13.8      M    M
 29000  -29.8 -21.6   270   39   20   6.8   3.8   44.9 112.8    13.1      M    M
 28000  -27.8 -18.0   275   37   19   6.8   3.7   43.6 110.5    12.3      M    M
 27000  -25.7 -14.3   275   34   18   6.8   3.7   42.4 108.4    11.5      M    M
 26000  -23.7 -10.7   275   32   16   6.8   3.7   41.4 106.5    10.8      M    M
 25000  -21.6  -6.9   280   29   15   6.3   3.5   40.5 104.9    10.2      M    M
 24000  -19.9  -3.8   285   27   14   5.8   3.2   39.0 102.3     9.1      M    M
 23000  -18.2  -0.8   275   28   14   5.8   3.2   37.5  99.6     8.0      M    M
 22000  -16.5   2.3   265   30   15   5.7   3.1   36.1  97.0     6.9      M    M
 21000  -14.8   5.4   270   27   14   5.8   3.2   34.6  94.3     5.7      M    M
 20000  -13.0   8.6   280   23   12   8.7   4.8   33.4  92.0     4.7      M    M
 19500  -11.7  10.9   280   23   12   8.4   4.6   33.1  91.6     4.5      M    M
 19000  -10.5  13.1   280   24   12   8.9   4.9   32.9  91.2     4.3      M    M
 18500   -9.1  15.6   280   23   12   9.2   5.0   32.8  91.0     4.2      M    M
 18000   -7.1  19.2   280   22   11   7.7   4.2   32.6  90.7     4.2      M    M
 17500   -6.1  21.0   275   21   11   6.6   3.6   32.0  89.7     3.7      M    M
 17000   -5.1  22.8   275   20   10   6.6   3.6   31.5  88.7     3.2      M    M
 16500   -4.1  24.6   275   20   10   6.6   3.6   31.0  87.8     2.8      M    M
 16000   -3.1  26.4   275   20   10   6.6   3.6   30.5  86.8     2.3      M    M
 15500   -2.2  28.0   280   22   12   6.6   3.6   29.9  85.8     1.8      M    M
 15000   -1.2  29.8   280   25   13   6.5   3.5   29.4  84.9     1.4      M    M
 14500   -0.1  31.8   275   24   12   8.2   4.5   28.9  84.1     1.0      M    M
 14000    1.2  34.2   275   23   12   8.4   4.6   28.7  83.7     0.8      M    M
 13500    2.4  36.3   270   22   12   8.4   4.6   28.5  83.3     0.6      M    M
 13000    3.7  38.7   270   22   11   8.4   4.6   28.3  82.9     0.4      M    M
 12500    5.0  41.0   265   21   11   7.6   4.2   28.1  82.5     0.2      M    M
 12000    6.0  42.8   265   21   11   6.9   3.8   27.6  81.7    -0.2    571  2.9
 11500    7.0  44.6   265   20   10   6.4   3.5   27.1  80.8    -0.7    527  2.7
 11000    7.6  45.7   265   19   10   4.5   2.5   26.4  79.5    -1.5    492  2.5
 10500    8.5  47.3   265   18    9   9.8   5.4   26.0  78.8    -2.2    452  2.3
 10250    9.1  48.4   265   17    9   8.9   4.9   26.0  78.7    -2.3    426  2.2
 10000    9.7  49.5   265   16    8   8.9   4.9   25.9  78.6    -2.4    400  2.0
  9750   10.4  50.7   265   15    8   9.5   5.2   25.8  78.5    -2.5    372  1.9
  9500   11.1  52.0   270   14    7   9.4   5.1   25.8  78.4    -2.5    343  1.7
  9250   11.8  53.2   270   12    6   9.2   5.1   25.8  78.4    -2.5    315  1.6
  9000   12.5  54.5   270   11    6   9.9   5.4   25.7  78.3    -2.5    286  1.5
  8750   13.2  55.8   265    9    5   6.5   3.6   25.7  78.3    -2.6    258  1.3
  8500   13.5  56.3   255    7    4   3.2   1.8   25.2  77.4    -3.0    242  1.2
  8250   13.8  56.8   240    5    3   4.2   2.3   24.8  76.6    -3.5    227  1.2
  8000   14.0  57.2   215    4    2   3.7   2.0   24.3  75.8    -4.0    211  1.1
  7750   14.3  57.7   175    5    3   4.7   2.6   23.9  75.0    -4.4    195  1.0
  7500   14.6  58.3   155    8    4   0.8   0.5   23.4  74.2    -4.9    180  0.9
  7250   14.3  57.7   145   11    6  -4.0  -2.2   22.5  72.5    -5.9    181  0.9
  7000   14.0  57.2   140   14    7  -6.2  -3.4   21.4  70.5    -7.0    184  0.9
  6750   13.6  56.5   140   15    8  -3.5  -1.9   20.2  68.3    -8.2    188  1.0
  6500   13.6  56.5   140   15    8   4.1   2.2   19.5  67.1    -8.8    179  0.9
  6250   14.0  57.2   135   15    8   5.9   3.2   19.2  66.5    -9.2    160  0.8
  6000   14.4  57.9   135   15    8   5.3   2.9   18.8  65.9    -9.6    141  0.7
  5750   14.8  58.6   135   14    7   5.8   3.2   18.5  65.3    -9.9    122  0.6
  5500   15.2  59.4   130   12    6   4.6   2.6   18.2  64.7   -10.3    103  0.5
  5250   15.6  60.1   125   11    6   8.7   4.8   17.9  64.2   -10.7     84  0.4
  5000   16.0  60.8   120    9    5  -6.4  -3.5   17.6  63.6   -11.0     65  0.3

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

           09/13/2014 at 0900 MDT          |       09/13/2014 at 1200 MDT
                                           |
K index... +13.0  LI... +1.9               | K index... +6.7  LI... +1.2
CAPE... 0.0  CIN... -4.5                   | CAPE... +1.7  CIN... -1.9
                                           |
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 -64.8 -84.6  285  43 22   3.1   1.7 | -64.4 -83.9  280  46 24   3.4   1.9
 45000 -59.6 -75.3  280  56 29   4.1   2.3 | -58.7 -73.7  280  59 30   4.1   2.3
 40000 -53.3 -63.9  275  51 26   4.7   2.6 | -52.5 -62.5  275  53 27   3.5   1.9
 38000 -50.6 -59.1  270  47 24   4.6   2.5 | -50.4 -58.7  275  47 24   3.5   1.9
 36000 -47.8 -54.0  270  44 23   4.7   2.6 | -48.3 -54.9  270  41 21   3.6   2.0
 34000 -43.4 -46.1  270  42 22   8.4   4.6 | -43.3 -45.9  270  39 20   8.8   4.8
 32000 -37.7 -35.9  275  41 21   8.4   4.6 | -38.0 -36.4  270  38 20   8.8   4.8
 30000 -32.6 -26.7  275  39 20   8.5   4.7 | -33.0 -27.4  275  37 19   8.4   4.6
 29000 -30.1 -22.2  280  38 20   8.5   4.7 | -30.4 -22.7  275  37 19   8.4   4.6
 28000 -27.5 -17.5  280  37 19   8.0   4.4 | -27.9 -18.2  275  36 19   7.9   4.3
 27000 -25.6 -14.1  280  34 17   6.2   3.4 | -26.0 -14.8  275  33 17   6.4   3.5
 26000 -23.7 -10.7  285  31 16   6.2   3.4 | -24.0 -11.2  280  30 16   6.4   3.5
 25000 -21.9  -7.4  285  28 14   6.2   3.4 | -22.1  -7.8  280  27 14   6.4   3.5
 24000 -20.1  -4.2  285  27 14   5.7   3.1 | -20.4  -4.7  280  26 14   5.6   3.1
 23000 -18.4  -1.1  285  28 14   5.7   3.1 | -18.7  -1.7  285  26 14   5.6   3.1
 22000 -16.7   1.9  290  29 15   5.6   3.1 | -17.0   1.4  285  27 14   5.5   3.0
 21000 -14.9   5.2  290  28 14   6.3   3.4 | -15.1   4.8  285  26 14   6.8   3.7
 20000 -13.0   8.6  290  27 14   6.3   3.5 | -13.1   8.4  285  26 13   6.8   3.7
 19500 -12.1  10.2  290  26 13   6.3   3.5 | -11.6  11.1  285  26 13   6.8   3.8
 19000 -10.6  12.9  290  25 13   7.1   3.9 | -10.5  13.1  285  26 13   7.0   3.8
 18500  -9.6  14.7  285  25 13   7.1   3.9 |  -9.5  14.9  285  26 13   7.0   3.8
 18000  -8.6  16.5  285  25 13   7.0   3.9 |  -8.5  16.7  280  25 13   7.2   3.9
 17500  -7.5  18.5  285  25 13   7.0   3.9 |  -7.4  18.7  280  25 13   7.3   4.0
 17000  -6.5  20.3  285  26 13   7.1   3.9 |  -6.3  20.7  280  24 12   7.4   4.1
 16500  -5.4  22.3  285  25 13   7.7   4.2 |  -5.1  22.8  280  23 12   8.0   4.4
 16000  -4.3  24.3  285  25 13   7.7   4.2 |  -3.9  25.0  285  22 11   8.0   4.4
 15500  -3.2  26.2  285  25 13   8.0   4.4 |  -2.7  27.1  285  21 11   8.3   4.6
 15000  -2.1  28.2  285  24 12   8.1   4.5 |  -1.5  29.3  285  20 10   8.3   4.6
 14500  -0.9  30.4  280  23 12   8.5   4.7 |  -0.3  31.5  285  19 10   8.5   4.6
 14000   0.3  32.5  280  23 12   8.7   4.8 |   1.0  33.8  285  18  9   8.5   4.7
 13500   1.5  34.7  280  22 11   8.9   4.9 |   2.2  36.0  285  17  9   8.5   4.7
 13000   2.9  37.2  275  21 11   9.0   5.0 |   3.4  38.1  285  16  8   8.4   4.6
 12500   4.3  39.7  275  20 10   8.8   4.9 |   4.7  40.5  280  16  8   8.5   4.7
 12000   5.5  41.9  275  19 10   8.0   4.4 |   5.9  42.6  280  15  8   8.7   4.8
 11500   6.8  44.2  270  17  9   8.0   4.4 |   7.1  44.8  275  15  8   8.6   4.7
 11000   7.9  46.2  270  16  8   7.3   4.0 |   8.2  46.8  270  14  7   7.6   4.2
 10500   8.9  48.0  265  15  8   6.2   3.4 |   9.4  48.9  265  14  7   5.5   3.0
 10250   9.3  48.7  265  15  8   4.3   2.4 |   9.6  49.3  265  14  7   4.3   2.4
 10000   9.6  49.3  265  14  7   6.5   3.6 |  10.1  50.2  260  13  7   8.2   4.5
  9750  10.2  50.4  260  13  7   8.0   4.4 |  10.7  51.3  260  12  6   9.4   5.2
  9500  10.8  51.4  260  12  6   6.7   3.7 |  11.4  52.5  255  12  6   7.8   4.3
  9250  11.1  52.0  260  11  6   3.7   2.0 |  11.8  53.2  255  11  6   4.9   2.7
  9000  11.4  52.5  255  10  5   4.3   2.3 |  12.2  54.0  250  10  5   4.8   2.6
  8750  11.8  53.2  250   9  5   6.1   3.3 |  12.5  54.5  245   9  4   5.5   3.0
  8500  12.2  54.0  245   8  4   5.3   2.9 |  12.9  55.2  240   7  4   5.1   2.8
  8250  12.6  54.7  235   7  3   4.8   2.6 |  13.3  55.9  240   6  3   4.7   2.6
  8000  13.0  55.4  225   6  3   5.1   2.8 |  13.6  56.5  235   5  3   4.9   2.7
  7750  13.4  56.1  215   6  3   6.2   3.4 |  13.9  57.0  235   5  2   5.0   2.8
  7500  13.8  56.8  205   6  3   5.1   2.8 |  14.3  57.7  235   4  2   6.2   3.4
  7250  14.1  57.4  200   7  3   3.6   2.0 |  14.8  58.6  235   4  2   7.0   3.9
  7000  14.4  57.9  195   7  4   4.3   2.3 |  15.3  59.5  235   3  2   6.8   3.8
  6750  14.7  58.5  185   8  4   2.6   1.5 |  15.8  60.4  240   3  2   9.0   4.9
  6500  14.7  58.5  180   8  4  -0.5  -0.3 |  16.6  61.9  240   3  2  10.8   5.9
  6250  14.7  58.5  170   7  3  -1.2  -0.6 |  17.4  63.3  240   3  2  11.2   6.1
  6000  14.6  58.3  155   6  3  -1.9  -1.0 |  18.2  64.8  240   3  2   9.7   5.3
  5750  14.4  57.9  150   6  3   0.6   0.3 |  19.0  66.2  245   3  2  15.0   8.2
  5500  14.7  58.5  135   5  2   7.9   4.3 |  20.6  69.1  245   3  2  28.0  15.4
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/13/2014 at 1500 MDT          |       09/13/2014 at 1800 MDT
                                           |
K index... +12.3  LI... -0.9               | K index... +10.0  LI... -0.7
CAPE... +46.3  CIN... -64.2                | CAPE... +20.8  CIN... -99.6
                                           |
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 -66.1 -87.0  270  48 25   2.7   1.5 | -66.0 -86.8  270  51 26   2.2   1.2
 45000 -60.7 -77.3  275  57 30   5.5   3.0 | -60.7 -77.3  275  64 33   6.5   3.6
 40000 -52.6 -62.7  285  52 27   3.6   2.0 | -51.2 -60.2  290  67 35   2.4   1.3
 38000 -50.3 -58.5  285  44 23   3.8   2.1 | -49.5 -57.1  285  54 28   2.8   1.6
 36000 -48.0 -54.4  280  36 19   3.9   2.2 | -47.8 -54.0  285  42 21   3.0   1.6
 34000 -43.7 -46.7  275  35 18   8.4   4.6 | -43.8 -46.8  280  36 19   8.3   4.5
 32000 -38.7 -37.7  275  36 18   8.4   4.6 | -38.8 -37.8  280  33 17   8.3   4.5
 30000 -32.8 -27.0  275  35 18   8.8   4.8 | -33.0 -27.4  280  31 16   8.7   4.8
 29000 -30.2 -22.4  275  35 18   8.8   4.8 | -30.4 -22.7  285  31 16   8.7   4.8
 28000 -27.6 -17.7  275  35 18   7.8   4.3 | -27.7 -17.9  285  31 16   8.1   4.4
 27000 -25.6 -14.1  275  32 16   6.5   3.6 | -25.5 -13.9  285  29 15   7.3   4.0
 26000 -23.6 -10.5  275  29 15   6.5   3.6 | -23.3  -9.9  285  26 14   7.3   4.0
 25000 -21.7  -7.1  280  26 13   6.6   3.6 | -21.1  -6.0  285  24 12   7.5   4.1
 24000 -19.8  -3.6  280  25 13   6.0   3.3 | -19.3  -2.7  285  23 12   5.8   3.2
 23000 -18.0  -0.4  280  24 12   6.0   3.3 | -17.6   0.3  285  22 12   5.8   3.2
 22000 -16.2   2.8  285  23 12   6.0   3.3 | -15.8   3.6  280  22 11   5.8   3.2
 21000 -14.4   6.1  280  23 12   6.3   3.4 | -14.2   6.4  280  23 12   5.5   3.0
 20000 -12.5   9.5  280  24 12   6.3   3.5 | -12.6   9.3  280  24 12   5.6   3.0
 19500 -11.6  11.1  275  24 12   6.3   3.5 | -11.7  10.9  280  25 13   5.4   3.0
 19000 -10.6  12.9  275  24 12   6.9   3.8 | -10.8  12.6  280  25 13   8.3   4.6
 18500  -9.6  14.7  275  24 12   7.0   3.9 |  -9.5  14.9  280  24 12   8.8   4.8
 18000  -8.6  16.5  275  23 12   7.2   3.9 |  -8.1  17.4  280  24 12   8.6   4.7
 17500  -7.5  18.5  275  23 12   7.5   4.1 |  -7.0  19.4  275  22 11   7.9   4.3
 17000  -6.4  20.5  275  23 12   7.5   4.1 |  -5.8  21.6  275  21 11   7.9   4.3
 16500  -5.2  22.6  275  23 12   8.2   4.5 |  -4.6  23.7  275  20 10   8.2   4.5
 16000  -4.0  24.8  280  23 12   8.2   4.5 |  -3.4  25.9  275  19 10   8.3   4.5
 15500  -2.8  27.0  280  23 12   8.5   4.7 |  -2.2  28.0  270  18  9   8.5   4.6
 15000  -1.5  29.3  280  22 11   8.8   4.8 |  -1.0  30.2  270  17  9   8.7   4.7
 14500   0.5  32.9  280  21 11   8.5   4.6 |   0.9  33.6  265  17  9   9.2   5.0
 14000   1.7  35.1  275  20 10   8.4   4.6 |   2.3  36.1  265  17  9   9.3   5.1
 13500   3.0  37.4  275  18  9   8.8   4.8 |   3.7  38.7  265  17  9   9.1   5.0
 13000   4.3  39.7  275  17  9   9.0   4.9 |   5.0  41.0  265  17  9   9.0   4.9
 12500   5.6  42.1  270  15  8   8.9   4.9 |   6.4  43.5  265  17  9   9.1   5.0
 12000   7.0  44.6  270  14  7   8.9   4.9 |   7.7  45.9  265  16  8   9.2   5.0
 11500   8.3  46.9  265  14  7   8.9   4.9 |   9.1  48.4  265  15  8   9.0   5.0
 11000   9.5  49.1  265  13  7   8.6   4.7 |  10.4  50.7  265  14  7   8.6   4.7
 10500  10.8  51.4  260  13  7   4.1   2.3 |  11.7  53.1  265  13  7   5.5   3.0
 10250  10.9  51.6  260  13  7   5.2   2.9 |  12.0  53.6  265  13  7   6.3   3.5
 10000  11.7  53.1  260  13  6  12.1   6.6 |  12.8  55.0  265  12  6  11.0   6.0
  9750  12.4  54.3  260  12  6  11.1   6.1 |  13.5  56.3  265  12  6  10.3   5.6
  9500  13.2  55.8  260  12  6   8.6   4.7 |  14.3  57.7  265  11  6   8.4   4.6
  9250  13.6  56.5  260  12  6   6.0   3.3 |  14.8  58.6  265  11  6   6.7   3.7
  9000  14.1  57.4  260  11  6   7.8   4.3 |  15.3  59.5  265  10  5   8.4   4.6
  8750  14.6  58.3  265  10  5   8.1   4.5 |  16.0  60.8  265  10  5   9.1   5.0
  8500  15.2  59.4  265  10  5   6.5   3.6 |  16.6  61.9  265   9  5   7.5   4.1
  8250  15.6  60.1  265   8  4   5.2   2.8 |  17.0  62.6  270   8  4   5.9   3.2
  8000  16.0  60.8  270   7  3   5.7   3.1 |  17.5  63.5  270   7  4   6.2   3.4
  7750  16.4  61.5  270   6  3   6.3   3.5 |  17.9  64.2  270   6  3   6.2   3.4
  7500  16.9  62.4  275   5  2   8.2   4.5 |  18.3  64.9  275   4  2   6.2   3.4
  7250  17.5  63.5  275   4  2   9.2   5.0 |  18.7  65.7  275   3  2   6.1   3.3
  7000  18.2  64.8  280   4  2   8.7   4.8 |  19.1  66.4  270   2  1   6.8   3.7
  6750  18.8  65.8  280   4  2   9.9   5.4 |  19.6  67.3  265   2  1   8.8   4.8
  6500  19.6  67.3  280   4  2  11.1   6.1 |  20.3  68.5  265   2  1  10.2   5.6
  6250  20.5  68.9  280   4  2  11.5   6.3 |  21.0  69.8  265   2  1  10.8   5.9
  6000  21.3  70.3  275   4  2   9.7   5.3 |  21.8  71.2  265   2  1   9.5   5.2
  5750  22.0  71.6  280   4  2  11.1   6.1 |  22.4  72.3  260   2  1   8.2   4.5
  5500  23.0  73.4  280   4  2  14.6   8.0 |  23.1  73.6  265   2  1   8.5   4.6
  5250  24.0  75.2  280   4  2  11.8   6.5 |  23.7  74.7  265   2  1   8.2   4.5
  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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