Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231222
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0522 MST Sunday, November 23, 2014

This forecast is for Sunday, November 23, 2014:

If the trigger temperature of 42.7 F/5.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5696 ft MSL (857 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
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................. None
Thermal soaring outlook for Monday 11/24....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:06:11 / 16:54:56 MST
Total possible sunshine........... 9 hr 48 min 46 sec (588 min 46 sec)
Altitude of sun at 12:00:43 MST... 30.49 degrees

Upper air data from rawinsonde observation taken on 11/23/2014 at 0500 MST

Freezing level.................. 6735 ft MSL (1896 ft AGL)
Convective condensation level... 9477 ft MSL (4638 ft AGL)
Lifted condensation level....... 8837 ft MSL (3997 ft AGL)
Lifted index.................... +2.8
K index......................... +10.6

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  -56.9 -70.4   265   36   19   6.3   3.5      M     M       M      M    M
 45000  -51.9 -61.4   290   68   35   4.9   2.7      M     M       M      M    M
 40000  -47.1 -52.8   285   65   34   0.9   0.5      M     M       M      M    M
 38000  -47.4 -53.3   290   76   39   5.5   3.0      M     M       M      M    M
 36000  -43.9 -47.0   285   85   44   5.8   3.2      M     M       M      M    M
 34000  -41.1 -42.0   285   85   44   7.0   3.9      M     M       M      M    M
 32000  -39.2 -38.6   280   71   37   4.5   2.5      M     M       M      M    M
 30000  -40.1 -40.2   275   73   37   3.0   1.7      M     M       M      M    M
 29000  -39.4 -38.9   275   71   37  -1.6  -0.9      M     M       M      M    M
 28000  -39.9 -39.8   275   71   36  -1.8  -1.0      M     M       M      M    M
 27000  -40.4 -40.7   280   65   33  -1.8  -1.0      M     M       M      M    M
 26000  -40.8 -41.4   280   59   30   2.2   1.2      M     M       M      M    M
 25000  -39.9 -39.8   285   53   27   3.0   1.7      M     M       M      M    M
 24000  -39.5 -39.1   290   48   25   0.0   0.0   19.2  66.6    11.8      M    M
 23000  -39.4 -38.9   295   44   23  -2.8  -1.5   15.8  60.4     9.1      M    M
 22000  -38.2 -36.8   295   40   21   8.8   4.8   13.7  56.6     7.5      M    M
 21000  -35.5 -31.9   300   36   19   9.2   5.0   13.5  56.2     7.4      M    M
 20000  -32.7 -26.9   310   36   19   9.2   5.0   13.3  55.9     7.4      M    M
 19500  -31.3 -24.3   310   33   17   9.2   5.0   13.1  55.6     7.3      M    M
 19000  -30.0 -22.0   315   29   15   9.2   5.0   13.0  55.4     7.2      M    M
 18500  -28.6 -19.5   320   26   13   9.2   5.0   12.9  55.2     7.2      M    M
 18000  -27.2 -17.0   325   22   11   9.4   5.2   12.8  55.0     7.2      M    M
 17500  -25.0 -13.0   330   23   12   9.7   5.3   12.8  55.0     7.2      M    M
 17000  -23.6 -10.5   335   23   12   9.6   5.3   12.8  55.0     7.3      M    M
 16500  -22.3  -8.1   335   23   12   7.9   4.3   12.6  54.7     7.1      M    M
 16000  -21.1  -6.0   340   23   12   7.9   4.3   12.3  54.2     6.9      M    M
 15500  -19.8  -3.6   340   21   11   9.7   5.3   12.2  53.9     6.8      M    M
 15000  -18.4  -1.1   340   19   10   9.5   5.2   12.1  53.8     6.8      M    M
 14500  -16.9   1.6   330   21   11   9.5   5.2   12.1  53.8     6.8      M    M
 14000  -15.5   4.1   325   22   11   8.6   4.7   12.1  53.7     6.8      M    M
 13500  -14.5   5.9   320   21   11   6.7   3.7   11.6  52.8     6.4      M    M
 13000  -13.8   7.2   315   21   11   1.8   1.0   10.7  51.3     5.6      M    M
 12500  -13.6   7.5   310   23   12   4.9   2.7    9.5  49.1     4.4      M    M
 12000  -12.6   9.3   310   25   13   6.3   3.5    9.0  48.2     4.0      M    M
 11500  -11.6  11.1   315   28   14   2.5   1.4    8.5  47.3     3.5      M    M
 11000  -11.6  11.1   315   30   15   5.2   2.9    7.0  44.6     2.1      M    M
 10500  -10.5  13.1   315   25   13   8.6   4.7    6.7  44.1     1.8      M    M
 10250   -9.9  14.2   315   23   12   8.4   4.6    6.6  43.9     1.6      M    M
 10000   -9.3  15.3   315   21   11   9.1   5.0    6.5  43.7     1.5      M    M
  9750   -8.6  16.5   315   19   10   9.8   5.4    6.5  43.7     1.5      M    M
  9500   -7.8  18.0   315   19   10   9.3   5.1    6.5  43.7     1.5      M    M
  9250   -7.1  19.2   315   19   10   9.1   5.0    6.4  43.6     1.5      M    M
  9000   -6.5  20.3   315   19   10   9.2   5.0    6.4  43.5     1.5      M    M
  8750   -5.8  21.6   315   19   10   9.1   5.0    6.4  43.4     1.4      M    M
  8500   -5.1  22.8   315   20   10   9.2   5.1    6.3  43.4     1.4      M    M
  8250   -4.4  24.1   315   20   11   9.5   5.2    6.3  43.3     1.4      M    M
  8000   -3.7  25.3   315   21   11   9.7   5.3    6.3  43.3     1.4      M    M
  7750   -2.9  26.8   315   20   10   9.6   5.3    6.3  43.3     1.3      M    M
  7500   -2.2  28.0   315   20   10   9.6   5.3    6.3  43.3     1.3      M    M
  7250   -1.5  29.3   310   19   10   9.7   5.3    6.2  43.2     1.3      M    M
  7000   -0.8  30.6   310   18    9   9.2   5.0    6.2  43.2     1.3      M    M
  6750   -0.2  31.6   305   18    9   8.7   4.8    6.2  43.1     1.2      M    M
  6500    0.4  32.7   295   18    9   9.1   5.0    6.1  43.0     1.1      M    M
  6250    1.1  34.0   290   18    9   8.2   4.5    6.0  42.9     1.0      M    M
  6000    1.7  35.1   280   19   10  11.8   6.5    6.0  42.8     0.9      M    M
  5750    2.3  36.1   280   16    8  -1.6  -0.9    5.9  42.7     0.8      M    M
  5500    1.5  34.7   285   12    6  -8.3  -4.6    4.4  40.0    -0.8      M    M
  5250    1.5  34.7   295    9    4   6.7   3.7    3.7  38.7    -1.5      M    M
  5000    1.9  35.4   315    5    3   1.0   0.5    3.4  38.2    -1.8      M    M

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

           11/23/2014 at 0800 MST          |       11/23/2014 at 1100 MST
                                           |
K index... +21.9  LI... -0.2               | K index... +13.3  LI... +0.3
CAPE... +39.5  CIN... -7.3                 | CAPE... +6.8  CIN... -19.3
                                           |
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 -57.7 -71.9  275  42 21   3.5   1.9 | -57.1 -70.8  280  45 23   3.8   2.1
 45000 -52.5 -62.5  290  52 27   3.6   2.0 | -51.5 -60.7  295  43 22   4.0   2.2
 40000 -48.0 -54.4  300  76 39   2.8   1.5 | -48.3 -54.9  295  70 36   2.0   1.1
 38000 -46.2 -51.2  300  80 41   3.9   2.1 | -46.9 -52.4  295  77 40   2.9   1.6
 36000 -43.8 -46.8  300  73 38   3.9   2.1 | -45.2 -49.4  300  70 36   2.9   1.6
 34000 -41.5 -42.7  300  66 34   4.1   2.2 | -43.5 -46.3  300  63 32   2.8   1.5
 32000 -41.1 -42.0  300  61 32  -0.1  -0.1 | -42.6 -44.7  310  61 31   0.9   0.5
 30000 -41.2 -42.2  305  57 30  -0.1  -0.1 | -42.0 -43.6  320  61 31   0.9   0.5
 29000 -41.1 -42.0  305  54 28   0.6   0.3 | -41.7 -43.1  320  58 30   1.0   0.5
 28000 -41.0 -41.8  305  50 26   0.6   0.3 | -41.4 -42.5  320  54 28   1.0   0.5
 27000 -40.8 -41.4  305  45 23   0.6   0.3 | -41.1 -42.0  315  50 25   1.0   0.5
 26000 -40.7 -41.3  305  38 20  -0.9  -0.5 | -40.8 -41.4  315  45 23   2.2   1.2
 25000 -40.9 -41.6  305  30 15  -0.8  -0.4 | -40.1 -40.2  315  40 20   2.3   1.3
 24000 -41.2 -42.2  305  21 11  -0.9  -0.5 | -39.4 -38.9  315  34 18   2.3   1.3
 23000 -40.9 -41.6  300  14  7   7.4   4.1 | -38.7 -37.7  315  29 15   3.1   1.7
 22000 -38.7 -37.7  295  14  7   7.3   4.0 | -37.7 -35.9  315  24 12   3.3   1.8
 21000 -36.6 -33.9  290  14  7   7.3   4.0 | -36.7 -34.1  310  19 10   3.5   1.9
 20000 -34.1 -29.4  285  15  8   9.3   5.1 | -35.0 -31.0  310  17  9   8.6   4.7
 19500 -32.7 -26.9  285  15  8   9.4   5.2 | -33.7 -28.7  310  17  9   8.6   4.7
 19000 -31.3 -24.3  290  15  8   9.4   5.2 | -32.4 -26.3  315  18  9   8.6   4.7
 18500 -29.9 -21.8  290  16  8   9.4   5.2 | -31.2 -24.2  315  18  9   8.6   4.7
 18000 -28.5 -19.3  290  16  8   8.8   4.8 | -29.9 -21.8  315  18  9   8.3   4.5
 17500 -27.3 -17.1  295  16  8   8.4   4.6 | -28.7 -19.7  320  19 10   7.9   4.3
 17000 -26.0 -14.8  300  17  8   8.3   4.6 | -27.5 -17.5  325  20 11   7.9   4.3
 16500 -24.8 -12.6  305  17  9   7.8   4.3 | -26.3 -15.3  325  22 11   7.9   4.3
 16000 -23.7 -10.7  310  19 10   7.8   4.3 | -25.2 -13.4  330  23 12   7.8   4.3
 15500 -22.5  -8.5  315  20 10   7.8   4.3 | -23.3  -9.9  335  25 13   9.0   4.9
 15000 -21.4  -6.5  320  21 11   7.8   4.3 | -21.9  -7.4  335  26 13   9.0   4.9
 14500 -20.2  -4.4  320  22 11   7.9   4.3 | -20.6  -5.1  340  26 13   8.7   4.8
 14000 -19.0  -2.2  325  22 11   7.9   4.3 | -19.3  -2.7  345  26 13   8.7   4.8
 13500 -17.9  -0.2  325  23 12   8.4   4.6 | -18.1  -0.6  350  26 13   8.1   4.4
 13000 -16.0   3.2  330  23 12   8.7   4.7 | -16.9   1.6  355  25 13   8.1   4.5
 12500 -14.7   5.5  335  24 12   8.2   4.5 | -15.7   3.7  360  25 13   7.5   4.1
 12000 -13.5   7.7  335  24 12   8.2   4.5 | -14.6   5.7  360  26 13   7.6   4.2
 11500 -12.3   9.9  340  24 12   7.8   4.3 | -13.4   7.9  005  27 14   7.9   4.3
 11000 -11.2  11.8  340  23 12   7.8   4.3 | -12.3   9.9  005  28 14   7.7   4.2
 10500 -10.2  13.6  340  21 11   6.7   3.7 | -11.2  11.8  005  27 14   6.6   3.6
 10250  -9.7  14.5  340  20 11   6.0   3.3 | -10.8  12.6  005  27 14   5.9   3.2
 10000  -9.2  15.4  340  19 10   9.1   5.0 | -10.3  13.5  005  26 13   9.0   5.0
  9750  -8.4  16.9  340  18 10   9.5   5.2 |  -9.5  14.9  360  25 13   9.7   5.3
  9500  -7.9  17.8  340  17  9   6.5   3.5 |  -9.0  15.8  360  23 12   7.0   3.8
  9250  -7.4  18.7  335  16  8   7.7   4.2 |  -8.4  16.9  355  22 11   7.6   4.2
  9000  -6.9  19.6  335  15  8   5.8   3.2 |  -7.9  17.8  355  20 10   7.5   4.1
  8750  -6.5  20.3  330  15  8   4.9   2.7 |  -7.3  18.9  350  20 10   8.6   4.7
  8500  -6.1  21.0  330  15  8   6.0   3.3 |  -6.6  20.1  350  19 10   9.3   5.1
  8250  -5.7  21.7  325  15  8   5.8   3.2 |  -5.9  21.4  345  17  9   8.6   4.7
  8000  -5.2  22.6  325  15  8   6.1   3.3 |  -5.4  22.3  345  16  8   7.3   4.0
  7750  -4.8  23.4  320  15  8   5.7   3.1 |  -4.8  23.4  335  15  8   6.7   3.7
  7500  -4.4  24.1  315  15  7   4.9   2.7 |  -4.4  24.1  330  15  8   6.5   3.6
  7250  -4.0  24.8  315  14  7   6.4   3.5 |  -3.8  25.2  325  14  7   7.9   4.3
  7000  -3.5  25.7  305  14  7   7.7   4.2 |  -3.2  26.2  325  13  7   9.0   5.0
  6750  -2.9  26.8  300  14  7   6.4   3.5 |  -2.5  27.5  320  13  7   8.7   4.8
  6500  -2.5  27.5  295  13  7   6.0   3.3 |  -1.9  28.6  320  12  6   9.8   5.4
  6250  -2.0  28.4  290  13  6   6.5   3.6 |  -1.1  30.0  320  12  6  11.0   6.1
  6000  -1.6  29.1  285  11  6   6.6   3.6 |  -0.2  31.6  315  11  6  10.8   5.9
  5750  -1.1  30.0  280  10  5   6.7   3.7 |   0.5  32.9  315  11  6   9.9   5.4
  5500  -0.6  30.9  275   8  4   5.8   3.2 |   1.2  34.2  315  10  5   9.7   5.3
  5250  -0.3  31.5  275   7  4   4.5   2.5 |   2.0  35.6  315  10  5  10.6   5.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           11/23/2014 at 1400 MST          |       11/23/2014 at 1700 MST
                                           |
K index... +7.8  LI... -0.3                | K index... -1.1  LI... +0.9
CAPE... +52.8  CIN... -9.2                 | CAPE... 0.0  CIN... -3.7
                                           |
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 -58.1 -72.6  285  46 24   3.6   2.0 | -58.2 -72.8  290  47 24   2.7   1.5
 45000 -52.5 -62.5  300  50 26   3.7   2.0 | -54.2 -65.6  300  56 29   2.7   1.5
 40000 -49.0 -56.2  300  72 37   2.2   1.2 | -49.6 -57.3  305  69 35   2.9   1.6
 38000 -47.7 -53.9  300  78 40   2.2   1.2 | -48.0 -54.4  310  72 37   1.5   0.8
 36000 -46.3 -51.3  305  72 37   2.2   1.2 | -47.1 -52.8  310  71 37   1.5   0.8
 34000 -45.0 -49.0  310  67 34   2.2   1.2 | -46.3 -51.3  315  71 36   1.5   0.8
 32000 -44.2 -47.6  320  67 35   1.2   0.6 | -45.8 -50.4  320  72 37   0.7   0.4
 30000 -43.4 -46.1  325  71 36   1.1   0.6 | -45.4 -49.7  325  73 38   0.7   0.4
 29000 -43.0 -45.4  330  69 35   1.5   0.8 | -45.0 -49.0  325  74 38   1.6   0.9
 28000 -42.5 -44.5  330  65 34   1.5   0.8 | -44.5 -48.1  330  73 38   1.6   0.9
 27000 -42.1 -43.8  330  62 32   1.5   0.8 | -43.9 -47.0  330  73 37   1.6   0.9
 26000 -41.6 -42.9  330  58 30   1.7   0.9 | -43.3 -45.9  330  71 37   4.0   2.2
 25000 -41.2 -42.2  330  51 26   1.7   0.9 | -42.1 -43.8  335  68 35   3.7   2.1
 24000 -40.7 -41.3  330  45 23   1.6   0.9 | -41.0 -41.8  340  64 33   3.7   2.0
 23000 -40.0 -40.0  330  40 20   4.4   2.4 | -39.7 -39.5  340  61 32   6.4   3.5
 22000 -38.7 -37.7  325  35 18   4.4   2.4 | -37.9 -36.2  340  58 30   6.1   3.3
 21000 -37.4 -35.3  320  31 16   4.5   2.5 | -36.1 -33.0  345  55 28   6.1   3.3
 20000 -35.4 -31.7  320  29 15   8.4   4.6 | -34.1 -29.4  345  52 27   6.7   3.7
 19500 -34.2 -29.6  315  29 15   8.5   4.7 | -33.1 -27.6  340  50 26   6.7   3.7
 19000 -32.9 -27.2  315  29 15   8.6   4.7 | -32.1 -25.8  340  49 25   6.7   3.7
 18500 -31.6 -24.9  315  29 15   8.6   4.7 | -31.1 -24.0  340  47 24   6.7   3.7
 18000 -30.3 -22.5  310  29 15   8.5   4.7 | -30.1 -22.2  340  46 23   7.0   3.8
 17500 -29.1 -20.4  315  29 15   8.5   4.7 | -29.0 -20.2  340  44 23   7.1   3.9
 17000 -27.8 -18.0  315  29 15   8.3   4.6 | -28.0 -18.4  340  42 22   7.5   4.1
 16500 -26.6 -15.9  315  30 15   7.7   4.2 | -26.8 -16.2  340  40 21   8.4   4.6
 16000 -25.4 -13.7  320  30 16   7.7   4.2 | -25.5 -13.9  340  38 20   8.4   4.6
 15500 -24.3 -11.7  320  31 16   8.1   4.5 | -24.2 -11.6  340  36 19   9.1   5.0
 15000 -23.1  -9.6  320  31 16   8.1   4.4 | -22.9  -9.2  340  35 18   9.2   5.0
 14500 -21.8  -7.2  325  31 16   8.4   4.6 | -21.6  -6.9  340  33 17   7.6   4.2
 14000 -20.0  -4.0  330  32 16   8.4   4.6 | -20.4  -4.7  340  32 17   7.7   4.2
 13500 -18.7  -1.7  335  32 16   8.4   4.6 | -18.7  -1.7  340  31 16   7.9   4.3
 13000 -17.5   0.5  340  32 17   8.4   4.6 | -17.5   0.5  340  31 16   7.7   4.2
 12500 -16.2   2.8  340  33 17   8.5   4.7 | -16.5   2.3  340  29 15   7.1   3.9
 12000 -14.9   5.2  345  33 17   8.5   4.7 | -15.4   4.3  340  26 14   7.5   4.1
 11500 -13.7   7.3  350  31 16   8.4   4.6 | -14.2   6.4  340  25 13   8.4   4.6
 11000 -12.5   9.5  350  29 15   8.4   4.6 | -13.0   8.6  340  23 12   8.6   4.7
 10500 -11.2  11.8  350  27 14   8.1   4.4 | -11.7  10.9  340  22 11   9.4   5.1
 10250 -10.6  12.9  350  25 13   8.8   4.8 | -11.0  12.2  340  22 11   7.4   4.1
 10000 -10.0  14.0  350  23 12   6.4   3.5 | -10.6  12.9  340  21 11   6.5   3.6
  9750  -9.6  14.7  345  23 12   7.2   4.0 | -10.0  14.0  345  21 11   9.6   5.3
  9500  -8.9  16.0  345  21 11  10.4   5.7 |  -9.2  15.4  345  20 10  10.8   5.9
  9250  -8.2  17.2  345  21 11   9.1   5.0 |  -8.4  16.9  345  20 10   9.9   5.4
  9000  -7.6  18.3  345  20 10   8.3   4.6 |  -7.8  18.0  345  19 10   9.1   5.0
  8750  -7.0  19.4  340  19 10   8.6   4.7 |  -7.1  19.2  345  19 10   9.8   5.4
  8500  -6.3  20.7  340  18  9   9.1   5.0 |  -6.3  20.7  345  19 10  10.5   5.7
  8250  -5.7  21.7  340  18  9   9.4   5.2 |  -5.6  21.9  345  18  9   9.8   5.4
  8000  -4.9  23.2  335  17  9  10.0   5.5 |  -4.9  23.2  345  18  9   9.3   5.1
  7750  -4.2  24.4  335  17  9   9.8   5.4 |  -4.2  24.4  345  18  9   9.3   5.1
  7500  -3.5  25.7  335  16  8   9.7   5.3 |  -3.5  25.7  345  18  9   9.3   5.1
  7250  -2.7  27.1  335  16  8   9.8   5.4 |  -2.8  27.0  345  17  9   9.8   5.4
  7000  -2.0  28.4  330  15  8   9.9   5.4 |  -2.0  28.4  345  17  9   9.9   5.4
  6750  -1.2  29.8  330  15  7   9.8   5.4 |  -1.3  29.7  345  16  8   9.0   4.9
  6500  -0.5  31.1  330  14  7  10.2   5.6 |  -0.7  30.7  340  15  8   8.8   4.8
  6250   0.3  32.5  330  13  7  10.7   5.9 |   0.0  32.0  340  14  7   8.6   4.7
  6000   1.1  34.0  325  12  6  10.3   5.6 |   0.7  33.3  340  12  6  10.2   5.6
  5750   1.8  35.2  325  11  6   9.0   5.0 |   1.3  34.3  340   9  5   3.8   2.1
  5500   2.4  36.3  325  11  6   8.3   4.6 |   1.1  34.0  340   8  4  -5.3  -2.9
  5250   3.0  37.4  325  11  6   9.1   5.0 |   0.8  33.4  345   7  3  -1.2  -0.7
  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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