Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0637 MDT Tuesday, September 23, 2014

This forecast is for Tuesday, September 23, 2014:

If the trigger temperature of 74.8 F/23.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 614 ft/min (3.1 m/s)
   Maximum height of thermals.................. 14262 ft MSL (9423 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9484 ft MSL (4644 ft AGL)
Thermal soaring outlook for Wednesday 09/24.... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:02:46 / 19:11:01 MDT
Total possible sunshine........... 12 hr 8 min 16 sec (728 min 16 sec)
Altitude of sun at 13:06:24 MDT... 50.62 degrees

Upper air data from rawinsonde observation taken on 09/23/2014 at 0600 MDT

Freezing level.................. 13671 ft MSL (8832 ft AGL)
Convective condensation level... 12336 ft MSL (7497 ft AGL)
Lifted condensation level....... 13124 ft MSL (8285 ft AGL)
Lifted index.................... -0.2
K index......................... +24.6

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  -66.1 -87.0   285   39   20   6.1   3.3   85.1 185.2    33.5      M    M
 45000  -58.7 -73.7   280   43   22   6.3   3.5   71.6 160.8    27.6      M    M
 40000  -50.0 -58.0   280   50   26   6.2   3.4   62.5 144.5    23.5      M    M
 38000  -46.3 -51.3   275   49   25   6.2   3.4   59.1 138.4    21.8      M    M
 36000  -42.6 -44.7   275   49   25   6.1   3.4   56.5 133.6    20.5      M    M
 34000  -39.9 -39.8   275   46   24   3.6   2.0   52.0 125.7    17.8      M    M
 32000  -39.1 -38.4   270   43   22   8.7   4.8   44.1 111.3    12.4      M    M
 30000  -33.9 -29.0   275   40   21   8.6   4.7   43.2 109.8    12.1      M    M
 29000  -31.2 -24.2   275   39   20   9.3   5.1   42.8 109.1    12.0      M    M
 28000  -28.4 -19.1   280   39   20   9.3   5.1   42.6 108.8    11.9      M    M
 27000  -25.6 -14.1   280   38   20   9.3   5.1   42.5 108.6    12.0      M    M
 26000  -22.9  -9.2   285   38   19   9.0   4.9   42.3 108.1    11.9      M    M
 25000  -20.2  -4.4   285   37   19   9.5   5.2   42.1 107.7    11.9      M    M
 24000  -17.8  -0.0   290   35   18   7.4   4.1   41.2 106.1    11.3      M    M
 23000  -15.6   3.9   290   33   17   7.4   4.1   40.2 104.3    10.7      M    M
 22000  -13.4   7.9   290   31   16   7.4   4.1   39.3 102.8    10.1      M    M
 21000  -11.2  11.8   290   28   15   7.4   4.1   38.6 101.4     9.5      M    M
 20000   -8.9  16.0   290   26   13   7.4   4.1   37.9 100.3     9.1      M    M
 19500   -7.8  18.0   285   24   12   5.9   3.3   37.5  99.4     8.8      M    M
 19000   -7.2  19.0   275   23   12   4.2   2.3   36.6  97.8     8.0      M    M
 18500   -6.6  20.1   270   22   11   4.6   2.5   35.6  96.0     7.1      M    M
 18000   -6.4  20.5   270   21   11   0.3   0.2   34.3  93.8     6.0      M    M
 17500   -6.9  19.6   265   20   11  -3.6  -1.9   31.6  88.9     3.2      M    M
 17000   -6.4  20.5   260   20   10   6.2   3.4   30.6  87.1     2.3      M    M
 16500   -5.5  22.1   260   19   10   6.0   3.3   29.9  85.9     1.7      M    M
 16000   -4.6  23.7   255   19   10   5.9   3.3   29.3  84.8     1.2      M    M
 15500   -3.7  25.3   265   19   10   7.2   3.9   28.7  83.7     0.7      M    M
 15000   -2.5  27.5   275   19   10   7.7   4.2   28.4  83.1     0.4      M    M
 14500   -1.3  29.7   285   19   10   7.6   4.2   28.1  82.5     0.2      M    M
 14000   -0.4  31.3   290   20   10   6.0   3.3   27.6  81.6    -0.4    788  4.0
 13500    0.4  32.7   290   19   10   7.5   4.1   27.0  80.6    -1.1    748  3.8
 13000    1.5  34.7   290   17    9   8.0   4.4   26.7  80.1    -1.4    699  3.6
 12500    2.7  36.9   295   16    8   8.0   4.4   26.5  79.6    -1.7    650  3.3
 12000    4.0  39.2   295   15    8   9.2   5.1   26.3  79.3    -1.9    597  3.0
 11500    5.3  41.5   295   13    7   9.1   5.0   26.2  79.1    -2.0    542  2.8
 11000    6.6  43.9   295   11    6   8.6   4.7   26.0  78.9    -2.2    488  2.5
 10500    7.8  46.0   295    9    5   8.4   4.6   25.9  78.6    -2.4    438  2.2
 10250    8.4  47.1   295    8    4   8.1   4.5   25.7  78.3    -2.6    413  2.1
 10000    9.0  48.2   290    8    4   8.0   4.4   25.6  78.1    -2.7    388  2.0
  9750    9.6  49.3   290    7    4   8.0   4.4   25.5  77.9    -2.9    362  1.8
  9500   10.2  50.4   285    6    3   8.0   4.4   25.3  77.6    -3.0    336  1.7
  9250   10.8  51.4   280    6    3   8.0   4.4   25.2  77.4    -3.1    310  1.6
  9000   11.4  52.5   275    5    3   8.0   4.4   25.1  77.2    -3.2    284  1.4
  8750   12.1  53.8   265    4    2   8.0   4.4   25.0  76.9    -3.3    258  1.3
  8500   12.7  54.9   255    3    2   8.2   4.5   24.8  76.7    -3.5    233  1.2
  8250   13.3  55.9   235    3    2   8.2   4.5   24.7  76.5    -3.6    208  1.1
  8000   13.8  56.8   215    3    2   8.2   4.5   24.6  76.3    -3.7    183  0.9
  7750   14.4  57.9   210    5    3   8.2   4.5   24.5  76.0    -3.9    158  0.8
  7500   15.0  59.0   210    7    4   8.2   4.5   24.3  75.8    -4.1    133  0.7
  7250   15.6  60.1   210    9    5   8.3   4.6   24.2  75.6    -4.2    108  0.5
  7000   16.2  61.2   210   12    6   7.9   4.3   24.1  75.4    -4.4     83  0.4
  6750   16.6  61.9   200   12    6   3.7   2.0   23.9  74.9    -4.7     63  0.3
  6500   16.7  62.1   185   12    6   0.4   0.2   23.2  73.8    -5.3     53  0.3
  6250   16.8  62.2   175   13    7   3.3   1.8   22.6  72.7    -6.0     43  0.2
  6000   17.1  62.8   165   15    7   6.1   3.4   22.2  72.0    -6.4     26  0.1
  5750   17.7  63.9   155   14    7  10.7   5.9   22.1  71.8    -6.6      2  0.0
  5500   18.2  64.8   150   13    6  -2.8  -1.5   21.9  71.5    -6.8      M    M
  5250   17.2  63.0   145   11    6 -14.6  -8.0   20.2  68.4    -8.5      1  0.0
  5000   16.8  62.2   135   10    5   7.1   3.9   19.1  66.4    -9.7      6  0.0

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

           09/23/2014 at 0900 MDT          |       09/23/2014 at 1200 MDT
                                           |
K index... +26.7  LI... +0.7               | K index... +15.6  LI... 0.0
CAPE... +289.1  CIN... -52.2               | CAPE... +400.3  CIN... -32.2
                                           |
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  300  21 11   3.4   1.9 | -64.9 -84.8  290  16  8   3.3   1.8
 45000 -58.2 -72.8  295  35 18   5.5   3.0 | -58.3 -72.9  295  32 17   6.1   3.3
 40000 -49.9 -57.8  295  39 20   5.8   3.2 | -49.3 -56.7  295  38 20   5.3   2.9
 38000 -46.4 -51.5  290  40 21   5.8   3.2 | -46.2 -51.2  295  38 20   5.3   2.9
 36000 -43.0 -45.4  290  41 21   5.7   3.2 | -43.0 -45.4  290  38 20   5.3   2.9
 34000 -40.5 -40.9  290  40 21   3.6   2.0 | -40.6 -41.1  295  37 19   3.6   2.0
 32000 -38.1 -36.6  290  38 20   3.3   1.8 | -38.2 -36.8  300  35 18   3.3   1.8
 30000 -33.7 -28.7  290  37 19   8.1   4.4 | -33.8 -28.8  305  34 17   8.0   4.4
 29000 -31.3 -24.3  295  37 19   8.1   4.4 | -31.4 -24.5  305  33 17   8.0   4.4
 28000 -28.9 -20.0  295  36 19   8.6   4.7 | -29.0 -20.2  305  32 16   8.4   4.6
 27000 -26.2 -15.2  295  35 18   8.9   4.9 | -26.4 -15.5  305  31 16   8.7   4.8
 26000 -23.6 -10.5  295  34 17   9.0   4.9 | -23.8 -10.8  305  31 16   8.7   4.8
 25000 -20.9  -5.6  295  33 17   9.0   4.9 | -21.3  -6.3  305  30 16   8.7   4.8
 24000 -18.4  -1.1  300  32 16   8.0   4.4 | -18.8  -1.8  305  30 15   8.1   4.5
 23000 -16.0   3.2  300  32 16   8.0   4.4 | -16.4   2.5  310  29 15   8.2   4.5
 22000 -13.6   7.5  305  31 16   8.0   4.4 | -13.9   7.0  310  29 15   8.1   4.5
 21000 -11.2  11.8  305  30 15   7.7   4.2 | -11.5  11.3  315  26 14   7.9   4.3
 20000  -8.9  16.0  305  28 15   7.7   4.2 |  -9.1  15.6  315  24 12   7.9   4.3
 19500  -7.8  18.0  305  27 14   7.9   4.3 |  -7.9  17.8  320  23 12   7.9   4.4
 19000  -6.7  19.9  305  26 14   5.7   3.1 |  -6.2  20.8  315  21 11   7.6   4.1
 18500  -5.5  22.1  305  24 12   5.5   3.0 |  -5.1  22.8  315  21 11   7.7   4.2
 18000  -4.9  23.2  300  22 12   1.3   0.7 |  -4.1  24.6  310  20 10   4.4   2.4
 17500  -5.0  23.0  295  20 10   0.4   0.2 |  -3.5  25.7  310  20 10   3.7   2.0
 17000  -5.1  22.8  290  18  9   1.4   0.8 |  -3.0  26.6  305  19 10   3.4   1.9
 16500  -4.7  23.5  285  17  9   4.3   2.3 |  -2.6  27.3  300  18  9   2.5   1.4
 16000  -4.2  24.4  280  16  8   4.0   2.2 |  -2.3  27.9  295  18  9   2.7   1.5
 15500  -3.4  25.9  275  16  8   7.7   4.2 |  -1.9  28.6  290  18  9   3.4   1.8
 15000  -2.3  27.9  270  17  9   7.6   4.2 |  -1.5  29.3  285  18  9   3.4   1.9
 14500  -1.2  29.8  265  18  9   7.3   4.0 |  -1.0  30.2  280  19 10   6.3   3.5
 14000  -0.2  31.6  270  18  9   7.2   3.9 |  -0.0  32.0  275  19 10   7.3   4.0
 13500   0.8  33.4  270  18  9   7.6   4.2 |   1.0  33.8  275  20 10   8.1   4.5
 13000   1.9  35.4  270  17  9   8.0   4.4 |   2.2  36.0  275  20 10   8.8   4.8
 12500   3.1  37.6  275  16  8   8.2   4.5 |   3.5  38.3  275  19 10   8.7   4.8
 12000   4.3  39.7  280  15  8   8.5   4.6 |   4.7  40.5  280  17  9   8.3   4.6
 11500   5.5  41.9  285  14  7   8.4   4.6 |   5.9  42.6  285  16  8   8.2   4.5
 11000   6.6  43.9  290  12  6   7.9   4.3 |   7.0  44.6  290  14  7   7.5   4.1
 10500   7.8  46.0  295  11  6   6.2   3.4 |   8.1  46.6  295  12  6   4.4   2.4
 10250   8.2  46.8  295  11  6   5.8   3.2 |   8.3  46.9  300  11  6   4.4   2.4
 10000   8.7  47.7  295  10  5   9.3   5.1 |   8.9  48.0  305  10  5  10.4   5.7
  9750   9.4  48.9  300  10  5  10.3   5.7 |   9.7  49.5  305   9  5  11.3   6.2
  9500  10.1  50.2  300   9  5   8.6   4.7 |  10.5  50.9  310   9  4   9.2   5.0
  9250  10.6  51.1  300   9  5   5.9   3.2 |  11.0  51.8  310   8  4   6.1   3.4
  9000  11.1  52.0  305   8  4   7.9   4.4 |  11.5  52.7  310   7  4   8.4   4.6
  8750  11.8  53.2  305   8  4  10.5   5.7 |  12.2  54.0  310   7  3  10.8   5.9
  8500  12.5  54.5  305   7  4   8.3   4.6 |  12.9  55.2  310   6  3   8.6   4.7
  8250  13.0  55.4  300   7  3   7.0   3.8 |  13.4  56.1  310   5  3   7.1   3.9
  8000  13.5  56.3  295   6  3   7.1   3.9 |  14.0  57.2  305   4  2   7.5   4.1
  7750  13.9  57.0  290   5  3   6.4   3.5 |  14.5  58.1  300   3  2   7.4   4.1
  7500  14.4  57.9  280   4  2   5.3   2.9 |  15.0  59.0  295   2  1   8.2   4.5
  7250  14.7  58.5  255   3  1   4.5   2.5 |  15.6  60.1  285   2  1   8.6   4.7
  7000  15.1  59.2  215   2  1   5.0   2.7 |  16.2  61.2  275   1  1   8.7   4.8
  6750  15.4  59.7  185   3  2   4.5   2.5 |  16.8  62.2  260   1  1   9.8   5.4
  6500  15.7  60.3  170   4  2   3.2   1.8 |  17.6  63.7  255   1  1  10.5   5.8
  6250  16.0  60.8  160   4  2   2.7   1.5 |  18.4  65.1  255   2  1  10.4   5.7
  6000  16.2  61.2  150   5  2   3.5   1.9 |  19.1  66.4  250   2  1  10.4   5.7
  5750  16.5  61.7  145   5  2   7.2   3.9 |  20.0  68.0  250   2  1  16.3   8.9
  5500  17.2  63.0  140   4  2  11.4   6.3 |  21.6  70.9  255   1  1  26.2  14.4
  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

           09/23/2014 at 1500 MDT          |       09/23/2014 at 1800 MDT
                                           |
K index... +13.7  LI... +0.6               | K index... +9.2  LI... +0.8
CAPE... +191.9  CIN... -78.3               | CAPE... +103.5  CIN... -148.0
                                           |
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 -65.3 -85.5  285  21 11   3.7   2.0 | -65.6 -86.1  290  23 12   3.6   2.0
 45000 -58.2 -72.8  295  33 17   6.2   3.4 | -58.4 -73.1  305  32 16   6.6   3.6
 40000 -49.2 -56.6  300  39 20   4.5   2.4 | -49.0 -56.2  310  37 19   3.8   2.1
 38000 -46.6 -51.9  305  40 20   4.4   2.4 | -46.7 -52.1  320  39 20   3.7   2.0
 36000 -43.9 -47.0  305  41 21   4.4   2.4 | -44.5 -48.1  330  42 21   3.6   2.0
 34000 -41.1 -42.0  310  40 21   4.9   2.7 | -41.5 -42.7  330  43 22   5.4   3.0
 32000 -38.1 -36.6  315  40 21   5.0   2.7 | -38.2 -36.8  330  45 23   5.5   3.0
 30000 -33.2 -27.8  320  38 20   8.1   4.4 | -32.9 -27.2  330  42 21   8.6   4.7
 29000 -30.8 -23.4  320  37 19   8.1   4.4 | -30.3 -22.5  330  40 20   8.6   4.7
 28000 -28.4 -19.1  320  35 18   8.1   4.4 | -27.8 -18.0  335  37 19   8.3   4.5
 27000 -25.9 -14.6  320  33 17   8.1   4.4 | -25.3 -13.5  335  35 18   8.2   4.5
 26000 -23.5 -10.3  315  31 16   8.1   4.5 | -22.9  -9.2  335  32 17   8.2   4.5
 25000 -21.1  -6.0  315  29 15   8.1   4.5 | -20.4  -4.7  335  30 15   8.1   4.5
 24000 -18.7  -1.7  315  29 15   8.2   4.5 | -18.1  -0.6  330  28 15   7.8   4.3
 23000 -16.2   2.8  315  28 14   8.2   4.5 | -15.8   3.6  330  27 14   7.8   4.3
 22000 -13.8   7.2  315  27 14   8.1   4.5 | -13.4   7.9  330  26 14   7.7   4.3
 21000 -11.4  11.5  315  25 13   8.0   4.4 | -11.2  11.8  325  24 13   7.6   4.2
 20000  -8.9  16.0  315  22 11   8.0   4.4 |  -8.9  16.0  325  22 11   7.6   4.2
 19500  -7.7  18.1  315  21 11   8.0   4.4 |  -7.8  18.0  325  21 11   7.7   4.2
 19000  -6.5  20.3  315  20 10   7.6   4.2 |  -6.7  19.9  320  20 10   7.4   4.0
 18500  -5.4  22.3  315  19 10   7.6   4.2 |  -5.5  22.1  320  19 10   7.4   4.1
 18000  -4.2  24.4  315  19 10   7.1   3.9 |  -4.3  24.3  320  18  9   7.2   3.9
 17500  -3.2  26.2  315  18  9   6.3   3.5 |  -3.3  26.1  320  18  9   6.7   3.7
 17000  -2.3  27.9  315  17  9   6.6   3.6 |  -2.3  27.9  325  17  9   6.8   3.8
 16500  -1.6  29.1  315  17  9   3.5   1.9 |  -1.4  29.5  325  16  8   5.5   3.0
 16000  -1.0  30.2  315  16  8   3.8   2.1 |  -0.6  30.9  325  15  8   5.7   3.1
 15500  -0.5  31.1  315  15  8   3.7   2.1 |   0.2  32.4  330  14  7   5.1   2.8
 15000  -0.0  32.0  315  14  7   3.8   2.1 |   0.9  33.6  330  14  7   4.8   2.7
 14500   0.8  33.4  310  13  7   5.8   3.2 |   1.9  35.4  330  13  6   4.7   2.6
 14000   1.6  34.9  300  12  6   5.9   3.2 |   2.5  36.5  325  11  6   4.8   2.6
 13500   2.5  36.5  290  12  6   7.7   4.2 |   3.1  37.6  320  10  5   7.0   3.9
 13000   3.6  38.5  285  12  6   8.4   4.6 |   4.2  39.6  315   9  4   8.0   4.4
 12500   4.8  40.6  280  12  6   8.5   4.7 |   5.3  41.5  305   7  4   8.6   4.7
 12000   6.0  42.8  275  12  6   8.5   4.7 |   6.6  43.9  305   7  4   8.9   4.9
 11500   7.3  45.1  275  13  6   8.4   4.6 |   7.9  46.2  300   7  4   8.8   4.8
 11000   8.5  47.3  275  12  6   8.1   4.4 |   9.2  48.6  300   7  4   8.4   4.6
 10500   9.7  49.5  280  12  6   4.7   2.6 |  10.5  50.9  300   7  4   4.9   2.7
 10250   9.9  49.8  280  12  6   5.5   3.0 |  10.7  51.3  300   7  4   6.2   3.4
 10000  10.6  51.1  280  11  6  10.5   5.8 |  11.5  52.7  300   7  4  11.6   6.3
  9750  11.2  52.2  280  10  5   9.7   5.3 |  12.3  54.1  300   7  4  10.7   5.9
  9500  11.9  53.4  280  10  5   6.9   3.8 |  13.1  55.6  300   7  4   8.6   4.7
  9250  12.2  54.0  280   8  4   5.0   2.8 |  13.6  56.5  300   7  4   6.8   3.7
  9000  12.7  54.9  280   7  4   7.9   4.3 |  14.2  57.6  300   7  3   8.7   4.8
  8750  13.3  55.9  280   6  3   8.3   4.6 |  14.8  58.6  300   6  3   8.9   4.9
  8500  13.9  57.0  280   5  3   8.6   4.7 |  15.4  59.7  300   6  3   7.6   4.1
  8250  14.5  58.1  275   5  3   8.8   4.8 |  15.9  60.6  300   5  3   6.8   3.7
  8000  15.1  59.2  275   5  2   9.5   5.2 |  16.3  61.3  300   5  2   6.2   3.4
  7750  15.8  60.4  270   4  2  10.0   5.5 |  16.8  62.2  300   4  2   6.1   3.3
  7500  16.5  61.7  270   4  2   9.8   5.4 |  17.2  63.0  300   3  1   7.7   4.2
  7250  17.3  63.1  270   4  2   9.6   5.3 |  17.8  64.0  295   2  1   8.3   4.5
  7000  18.0  64.4  265   4  2  10.3   5.7 |  18.3  64.9  290   2  1   8.2   4.5
  6750  18.8  65.8  265   4  2  11.0   6.0 |  18.9  66.0  285   1  1   9.2   5.1
  6500  19.6  67.3  265   4  2  10.7   5.9 |  19.6  67.3  275   1  1  10.0   5.5
  6250  20.4  68.7  265   4  2  10.9   6.0 |  20.4  68.7  270   1  1  10.0   5.5
  6000  21.2  70.2  260   4  2  10.2   5.6 |  21.1  70.0  265   1  1  10.0   5.5
  5750  22.0  71.6  265   4  2  11.8   6.4 |  21.8  71.2  260   1  1   8.8   4.8
  5500  23.0  73.4  265   4  2  14.1   7.7 |  22.4  72.3  265   1  1   7.9   4.3
  5250  23.9  75.0  265   4  2  12.3   6.7 |  23.0  73.4  270   1  1   8.6   4.7
  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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