Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0638 MDT Monday, September 22, 2014

This forecast is for Monday, September 22, 2014:

If the trigger temperature of 73.8 F/23.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 282 ft/min (1.4 m/s)
   Maximum height of thermals.................. 11102 ft MSL (6263 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 0600 MDT
Time of overdevelopment........................ 0600 MDT
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................. 8174 ft MSL (3335 ft AGL)
Thermal soaring outlook for Tuesday 09/23...... Good

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

Remarks...

Sunrise/Sunset.................... 07:01:50 / 19:12:38 MDT
Total possible sunshine........... 12 hr 10 min 47 sec (730 min 47 sec)
Altitude of sun at 13:06:45 MDT... 51.01 degrees

Upper air data from rawinsonde observation taken on 09/22/2014 at 0600 MDT

Freezing level.................. 13944 ft MSL (9105 ft AGL)
Convective condensation level... 10321 ft MSL (5482 ft AGL)
Lifted condensation level....... 10653 ft MSL (5813 ft AGL)
Lifted index.................... -2.0
K index......................... +31.1

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  -65.8 -86.4   275   39   20   5.6   3.1   84.3 183.8    34.4      M    M
 45000  -58.7 -73.7   260   55   28   7.3   4.0   71.6 160.9    29.0      M    M
 40000  -48.0 -54.4   260   49   25   4.3   2.4   65.5 150.0    27.0      M    M
 38000  -46.1 -51.0   255   57   29   3.3   1.8   59.7 139.4    23.7      M    M
 36000  -43.6 -46.5   250   57   29  -2.0  -1.1   54.8 130.7    20.9      M    M
 34000  -40.0 -40.0   250   51   26   7.2   3.9   50.6 123.1    18.5      M    M
 32000  -36.6 -33.9   250   46   24   8.3   4.6   47.4 117.2    16.5      M    M
 30000  -32.5 -26.5   240   40   20   8.0   4.4   45.1 113.2    15.2      M    M
 29000  -30.1 -22.2   245   34   17   8.1   4.5   44.5 112.1    14.8      M    M
 28000  -27.6 -17.7   245   32   16   8.3   4.5   43.8 110.9    14.5      M    M
 27000  -25.2 -13.4   245   30   15   8.3   4.5   43.2 109.8    14.2      M    M
 26000  -22.7  -8.9   245   28   14   8.3   4.5   42.7 108.9    14.0      M    M
 25000  -20.2  -4.4   245   27   14   8.3   4.6   42.2 108.0    13.7      M    M
 24000  -17.8  -0.0   245   27   14   8.4   4.6   41.7 107.0    13.4      M    M
 23000  -15.5   4.1   240   26   14   6.2   3.4   40.9 105.5    12.9      M    M
 22000  -14.2   6.4   240   26   13   4.9   2.7   38.9 102.0    11.4      M    M
 21000  -12.0  10.4   240   25   13   5.6   3.1   38.0 100.4    10.8      M    M
 20000   -9.6  14.7   240   25   13   6.7   3.7   37.2  99.0    10.3      M    M
 19500   -9.0  15.8   235   24   13   2.7   1.5   36.3  97.3     9.5      M    M
 19000   -8.6  16.5   235   24   12   5.3   2.9   35.3  95.5     8.5      M    M
 18500   -7.8  18.0   235   24   12   5.4   3.0   33.9  93.1     7.2      M    M
 18000   -6.7  19.9   235   23   12   6.1   3.4   33.3  92.0     6.8      M    M
 17500   -5.4  22.3   235   23   12   7.6   4.2   32.9  91.1     6.7      M    M
 17000   -4.3  24.3   235   23   12   5.6   3.1   32.3  90.1     6.4      M    M
 16500   -3.7  25.3   230   23   12  -3.8  -2.1   31.4  88.6     5.6      M    M
 16000   -5.3  22.5   230   22   12  -2.3  -1.3   28.4  83.0     2.5      M    M
 15500   -4.2  24.4   230   22   11  16.7   9.2   28.3  82.9     2.2      M    M
 15000   -2.1  28.2   230   22   11   9.8   5.4   29.1  84.3     2.8      M    M
 14500   -1.1  30.0   230   21   11   7.2   3.9   28.6  83.5     2.3      M    M
 14000   -0.0  32.0   230   21   11   9.5   5.2   28.3  82.9     2.0      M    M
 13500    1.4  34.5   225   20   10   9.8   5.4   28.4  83.0     2.0      M    M
 13000    2.9  37.2   220   19   10   9.6   5.2   28.4  83.0     2.0      M    M
 12500    4.3  39.7   230   19   10   8.4   4.6   28.3  83.0     2.0      M    M
 12000    5.0  41.0   235   19   10   3.7   2.0   27.6  81.7     1.2      M    M
 11500    5.7  42.3   230   18    9   6.3   3.5   26.9  80.3     0.5      M    M
 11000    6.6  43.9   230   18    9   6.2   3.4   26.3  79.3    -0.1    473  2.4
 10500    7.4  45.3   225   17    9   7.5   4.1   25.7  78.3    -0.7    432  2.2
 10250    8.1  46.6   225   16    8   8.7   4.7   25.6  78.1    -0.8    405  2.1
 10000    8.6  47.5   220   15    8   7.6   4.2   25.5  77.8    -0.9    380  1.9
  9750    9.2  48.6   220   13    7   7.9   4.3   25.3  77.6    -1.1    356  1.8
  9500    9.8  49.6   220   12    6   7.8   4.3   25.2  77.3    -1.2    331  1.7
  9250   10.4  50.7   215   10    5   8.0   4.4   25.0  77.1    -1.4    306  1.6
  9000   11.0  51.8   210    9    5   7.4   4.0   24.9  76.8    -1.5    281  1.4
  8750   11.4  52.5   190   11    6   5.6   3.1   24.6  76.4    -1.8    260  1.3
  8500   11.8  53.2   180   14    7   6.7   3.7   24.3  75.8    -2.1    241  1.2
  8250   12.2  54.0   170   17    9  -0.4  -0.2   24.0  75.1    -2.5    223  1.1
  8000   11.8  53.2   165   20   11   0.8   0.4   23.0  73.3    -3.6    226  1.1
  7750   12.3  54.1   165   21   11   9.0   5.0   22.7  72.9    -3.9    204  1.0
  7500   12.9  55.2   165   22   11   8.3   4.6   22.6  72.7    -4.0    179  0.9
  7250   13.5  56.3   160   22   12   6.5   3.6   22.5  72.5    -4.2    155  0.8
  7000   13.6  56.5   160   23   12  -2.9  -1.6   21.9  71.5    -4.8    143  0.7
  6750   13.3  55.9   160   21   11   1.5   0.8   20.9  69.7    -5.8    146  0.7
  6500   13.8  56.8   155   19   10   9.5   5.2   20.8  69.4    -6.0    122  0.6
  6250   14.4  57.9   155   17    9   7.4   4.0   20.6  69.1    -6.2     97  0.5
  6000   14.9  58.8   150   15    8   7.8   4.3   20.5  68.9    -6.4     73  0.4
  5750   15.5  59.9   145   13    6   8.0   4.4   20.3  68.6    -6.6     49  0.3
  5500   16.1  61.0   140   11    6   6.7   3.7   20.2  68.3    -6.8     25  0.1
  5250   16.4  61.5   125    9    5   4.8   2.6   19.9  67.8    -7.1      7  0.0
  5000   16.8  62.2   110    8    4   4.4   2.4   19.5  67.1    -7.5      M    M

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

           09/22/2014 at 0900 MDT          |       09/22/2014 at 1200 MDT
                                           |
K index... +30.3  LI... -4.2               | K index... +13.8  LI... -3.9
CAPE... +913.3  CIN... -5.1                | CAPE... +750.6  CIN... -1.4
                                           |
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 -65.1 -85.2  285  32 17   3.8   2.1 | -64.6 -84.3  275  31 16   3.8   2.1
 45000 -58.2 -72.8  275  50 26   5.7   3.1 | -58.1 -72.6  275  50 26   5.5   3.0
 40000 -49.7 -57.5  265  53 27   5.1   2.8 | -49.9 -57.8  275  52 27   5.2   2.8
 38000 -46.7 -52.1  265  52 27   5.0   2.8 | -46.8 -52.2  270  50 26   5.2   2.8
 36000 -43.7 -46.7  260  51 26   5.0   2.8 | -43.7 -46.7  270  48 25   5.2   2.8
 34000 -39.7 -39.5  260  48 25   6.1   3.4 | -39.8 -39.6  270  43 22   5.9   3.2
 32000 -36.0 -32.8  260  45 23   5.9   3.3 | -36.2 -33.2  265  38 20   5.7   3.1
 30000 -31.6 -24.9  260  44 23   7.7   4.2 | -31.7 -25.1  265  39 20   8.0   4.4
 29000 -29.3 -20.7  260  44 22   7.8   4.3 | -29.3 -20.7  265  40 20   8.0   4.4
 28000 -27.0 -16.6  260  44 22   7.5   4.1 | -27.0 -16.6  265  41 21   7.9   4.3
 27000 -24.9 -12.8  260  43 22   7.2   3.9 | -24.7 -12.5  265  40 21   7.8   4.3
 26000 -22.8  -9.0  255  43 22   7.2   3.9 | -22.3  -8.1  265  40 21   7.8   4.3
 25000 -20.6  -5.1  255  43 22   7.3   4.0 | -20.0  -4.0  265  40 21   7.9   4.3
 24000 -18.7  -1.7  250  42 21   6.5   3.6 | -17.9  -0.2  265  39 20   6.8   3.7
 23000 -16.8   1.8  250  39 20   6.5   3.6 | -15.9   3.4  265  38 19   6.8   3.7
 22000 -14.9   5.2  245  37 19   6.5   3.6 | -13.9   7.0  260  37 19   6.9   3.8
 21000 -13.0   8.6  240  37 19   6.5   3.6 | -12.3   9.9  260  35 18   5.1   2.8
 20000 -11.1  12.0  240  37 19   6.5   3.6 | -10.8  12.6  255  33 17   5.1   2.8
 19500 -10.1  13.8  235  36 19   6.5   3.6 |  -9.6  14.7  250  31 16   5.2   2.9
 19000  -8.7  16.3  235  36 19   6.3   3.4 |  -8.7  16.3  250  31 16   6.4   3.5
 18500  -7.8  18.0  235  36 19   6.3   3.5 |  -7.7  18.1  250  31 16   6.3   3.5
 18000  -6.9  19.6  235  36 19   5.7   3.1 |  -6.7  19.9  250  32 16   6.5   3.6
 17500  -6.1  21.0  235  35 18   5.5   3.0 |  -5.7  21.7  250  33 17   6.7   3.7
 17000  -5.4  22.3  235  34 18   5.6   3.1 |  -4.6  23.7  250  33 17   6.6   3.6
 16500  -4.5  23.9  235  33 17   6.2   3.4 |  -3.7  25.3  250  34 18   5.2   2.9
 16000  -3.6  25.5  235  32 17   6.2   3.4 |  -3.0  26.6  250  35 18   5.4   3.0
 15500  -2.7  27.1  235  31 16   6.1   3.4 |  -2.2  28.0  250  35 18   5.7   3.1
 15000  -1.9  28.6  235  29 15   6.2   3.4 |  -1.4  29.5  250  35 18   6.0   3.3
 14500  -1.0  30.2  235  28 14   6.0   3.3 |  -0.7  30.7  250  35 18   5.8   3.2
 14000  -0.2  31.6  240  26 13   5.9   3.3 |   0.1  32.2  250  34 17   5.9   3.2
 13500   0.7  33.3  240  25 13   6.3   3.5 |   0.8  33.4  250  33 17   6.8   3.7
 13000   1.6  34.9  240  23 12   6.7   3.7 |   1.9  35.4  250  31 16   7.8   4.3
 12500   2.6  36.7  240  22 11   6.8   3.7 |   2.9  37.2  250  30 15   8.0   4.4
 12000   3.5  38.3  240  21 11   7.0   3.8 |   4.1  39.4  255  28 14   8.2   4.5
 11500   4.5  40.1  240  20 10   7.3   4.0 |   5.2  41.4  255  26 13   8.0   4.4
 11000   5.6  42.1  235  20 10   8.1   4.5 |   6.3  43.3  255  23 12   7.3   4.0
 10500   6.7  44.1  235  20 10   7.3   4.0 |   7.3  45.1  255  20 10   5.0   2.7
 10250   7.2  45.0  235  20 10   8.1   4.5 |   7.5  45.5  255  18  9   3.9   2.2
 10000   7.9  46.2  235  20 10  11.0   6.0 |   8.0  46.4  250  16  8   8.4   4.6
  9750   8.7  47.7  235  21 11  11.9   6.5 |   8.6  47.5  250  14  7   9.7   5.3
  9500   9.5  49.1  235  21 11  10.2   5.6 |   9.3  48.7  245  12  6   8.2   4.5
  9250  10.1  50.2  235  21 11   7.6   4.2 |   9.7  49.5  240  10  5   6.0   3.3
  9000  10.7  51.3  235  21 11   9.2   5.0 |  10.2  50.4  235   9  5   7.7   4.2
  8750  11.4  52.5  235  21 11  11.4   6.2 |  10.8  51.4  225   7  4   9.6   5.2
  8500  12.2  54.0  235  21 11   9.0   4.9 |  11.4  52.5  215   6  3   8.5   4.7
  8250  12.7  54.9  235  20 10   7.0   3.9 |  12.0  53.6  210   6  3   7.6   4.2
  8000  13.3  55.9  235  19 10   7.8   4.3 |  12.5  54.5  200   5  3   8.6   4.7
  7750  13.8  56.8  235  19 10   8.1   4.5 |  13.2  55.8  200   5  3  10.1   5.5
  7500  14.4  57.9  235  17  9   7.0   3.8 |  13.9  57.0  195   5  3  10.1   5.6
  7250  14.8  58.6  235  16  8   6.0   3.3 |  14.6  58.3  195   5  3   9.9   5.5
  7000  15.3  59.5  235  14  7   6.6   3.6 |  15.4  59.7  195   5  2   9.8   5.4
  6750  15.7  60.3  230  12  6   5.1   2.8 |  16.1  61.0  195   5  2   9.7   5.3
  6500  16.0  60.8  225  10  5   2.8   1.5 |  16.8  62.2  195   4  2  10.3   5.6
  6250  16.2  61.2  215   8  4   2.9   1.6 |  17.6  63.7  195   4  2  10.6   5.8
  6000  16.4  61.5  200   6  3   1.6   0.9 |  18.4  65.1  195   4  2  10.4   5.7
  5750  16.5  61.7  185   5  3   1.0   0.6 |  19.3  66.7  195   4  2  15.4   8.4
  5500  16.6  61.9  170   4  2   4.0   2.2 |  20.7  69.3  200   4  2  23.6  12.9
  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

           09/22/2014 at 1500 MDT          |       09/22/2014 at 1800 MDT
                                           |
K index... +19.7  LI... -2.5               | K index... +24.1  LI... -1.3
CAPE... +635.6  CIN... -2.1                | CAPE... +486.9  CIN... -29.4
                                           |
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 -64.6 -84.3  270  31 16   4.1   2.2 | -64.8 -84.6  270  31 16   4.3   2.3
 45000 -57.8 -72.0  275  47 24   5.4   3.0 | -57.4 -71.3  275  46 23   5.5   3.0
 40000 -49.6 -57.3  275  51 26   5.6   3.1 | -49.2 -56.6  280  57 29   4.8   2.6
 38000 -46.2 -51.2  275  49 25   5.7   3.1 | -46.3 -51.3  280  53 27   4.8   2.6
 36000 -42.8 -45.0  275  46 24   5.7   3.1 | -43.5 -46.3  280  49 25   4.8   2.6
 34000 -39.6 -39.3  275  44 22   5.2   2.9 | -40.4 -40.7  285  51 26   5.1   2.8
 32000 -36.0 -32.8  275  41 21   5.0   2.8 | -37.0 -34.6  290  55 28   4.8   2.6
 30000 -31.9 -25.4  275  41 21   7.1   3.9 | -32.5 -26.5  290  56 29   7.9   4.4
 29000 -29.8 -21.6  275  41 21   7.1   3.9 | -30.1 -22.2  290  57 29   7.9   4.4
 28000 -27.7 -17.9  275  41 21   8.1   4.4 | -27.7 -17.9  290  57 30   8.4   4.6
 27000 -25.1 -13.2  275  41 21   8.7   4.8 | -25.1 -13.2  290  56 29   8.6   4.7
 26000 -22.5  -8.5  275  42 22   8.7   4.8 | -22.5  -8.5  290  55 28   8.6   4.7
 25000 -19.9  -3.8  275  43 22   8.7   4.8 | -19.9  -3.8  290  53 27   8.7   4.7
 24000 -17.4   0.7  275  42 22   8.1   4.5 | -17.4   0.7  290  49 25   8.7   4.8
 23000 -15.0   5.0  275  41 21   8.2   4.5 | -14.8   5.4  290  45 23   8.7   4.8
 22000 -12.6   9.3  275  39 20   7.8   4.3 | -12.2  10.0  285  40 21   8.2   4.5
 21000 -10.9  12.4  275  38 19   5.2   2.9 | -10.3  13.5  285  37 19   5.9   3.2
 20000  -9.4  15.1  270  36 18   5.3   2.9 |  -8.6  16.5  285  35 18   6.0   3.3
 19500  -8.6  16.5  270  35 18   5.4   2.9 |  -7.8  18.0  285  33 17   6.2   3.4
 19000  -7.9  17.8  270  34 18   4.4   2.4 |  -7.0  19.4  285  32 16   4.5   2.5
 18500  -7.4  18.7  265  34 17   4.3   2.4 |  -6.4  20.5  285  30 16   4.4   2.4
 18000  -6.8  19.8  260  34 17   4.9   2.7 |  -5.9  21.4  285  29 15   4.4   2.4
 17500  -5.8  21.6  260  33 17   6.7   3.7 |  -5.3  22.5  280  28 15   3.9   2.1
 17000  -4.8  23.4  260  33 17   6.8   3.7 |  -4.7  23.5  280  28 14   3.8   2.1
 16500  -3.8  25.2  255  33 17   5.5   3.0 |  -4.0  24.8  275  28 14   5.9   3.3
 16000  -2.9  26.8  260  31 16   5.5   3.0 |  -3.1  26.4  275  27 14   6.1   3.4
 15500  -1.7  28.9  260  29 15   4.8   2.7 |  -2.2  28.0  275  27 14   6.6   3.6
 15000  -1.1  30.0  260  27 14   5.1   2.8 |  -0.6  30.9  275  26 13   7.2   4.0
 14500  -0.4  31.3  260  26 13   5.8   3.2 |   0.5  32.9  270  25 13   7.4   4.1
 14000   0.4  32.7  260  24 13   6.1   3.4 |   1.6  34.9  270  24 12   7.4   4.1
 13500   1.2  34.2  260  23 12   7.2   4.0 |   2.7  36.9  265  23 12   7.4   4.1
 13000   2.3  36.1  260  22 11   7.9   4.3 |   3.7  38.7  260  23 12   7.6   4.1
 12500   3.3  37.9  260  21 11   8.0   4.4 |   4.7  40.5  260  22 11   7.9   4.3
 12000   4.5  40.1  255  20 10   8.2   4.5 |   5.9  42.6  260  20 10   8.2   4.5
 11500   5.6  42.1  255  18 10   8.3   4.5 |   7.0  44.6  255  19 10   8.4   4.6
 11000   6.8  44.2  250  17  9   8.1   4.4 |   8.3  46.9  255  17  9   8.6   4.7
 10500   8.0  46.4  245  15  8   4.2   2.3 |   9.5  49.1  255  15  8   4.2   2.3
 10250   8.1  46.6  245  14  7   5.0   2.7 |   9.6  49.3  260  14  7   4.7   2.6
 10000   8.8  47.8  240  12  6  10.7   5.9 |  10.3  50.5  255  13  7  10.8   5.9
  9750   9.5  49.1  235  11  6   9.8   5.4 |  10.9  51.6  255  12  6   9.8   5.4
  9500  10.2  50.4  225   9  5   7.7   4.2 |  11.6  52.9  255  11  5   7.8   4.3
  9250  10.6  51.1  225   9  4   6.1   3.4 |  12.0  53.6  255   9  5   5.6   3.1
  9000  11.2  52.2  220   8  4   9.0   5.0 |  12.5  54.5  255   8  4   7.4   4.1
  8750  11.8  53.2  215   7  4   9.7   5.3 |  13.0  55.4  255   7  4   8.0   4.4
  8500  12.5  54.5  210   7  3   9.4   5.2 |  13.6  56.5  255   6  3   7.1   3.9
  8250  13.2  55.8  210   7  3   9.3   5.1 |  14.0  57.2  250   5  2   6.6   3.6
  8000  13.8  56.8  210   6  3   9.7   5.3 |  14.5  58.1  245   4  2   6.3   3.5
  7750  14.6  58.3  210   6  3  10.0   5.5 |  14.9  58.8  245   3  1   6.4   3.5
  7500  15.3  59.5  210   6  3  10.0   5.5 |  15.5  59.9  245   2  1   8.8   4.8
  7250  16.1  61.0  210   6  3   9.9   5.5 |  16.2  61.2  245   2  1  10.1   5.6
  7000  16.8  62.2  210   6  3  10.1   5.5 |  16.9  62.4  245   2  1   9.2   5.1
  6750  17.6  63.7  210   6  3  10.6   5.8 |  17.6  63.7  245   2  1   9.4   5.2
  6500  18.4  65.1  210   6  3  10.7   5.9 |  18.3  64.9  245   2  1  10.2   5.6
  6250  19.2  66.6  210   6  3  11.0   6.0 |  19.1  66.4  245   2  1  10.7   5.8
  6000  20.0  68.0  210   6  3   9.7   5.3 |  19.8  67.6  250   2  1   9.3   5.1
  5750  20.7  69.3  210   6  3  10.5   5.8 |  20.4  68.7  250   2  1   7.8   4.3
  5500  21.6  70.9  210   6  3  12.9   7.1 |  21.0  69.8  250   2  1   8.1   4.4
  5250  22.4  72.3  215   6  3  11.0   6.0 |  21.6  70.9  255   2  1   7.8   4.3
  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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