Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 291236
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0636 MDT Friday, July 29, 2016

This forecast is for Friday, July 29, 2016:

If the trigger temperature of 90.6 F/32.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1835 ft/min (9.3 m/s)
   Maximum height of thermals.................. 23214 ft MSL (18375 ft AGL)

Forecast maximum temperature................... 100.0 F/38.2 C
Time of trigger temperature.................... 1130 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................. 12756 ft MSL (7917 ft AGL)
Thermal soaring outlook for Saturday 07/30..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:12:30 / 20:28:56 MDT
Total possible sunshine........... 14 hr 16 min 26 sec (856 min 26 sec)
Altitude of sun at 13:20:31 MDT... 69.36 degrees

Upper air data from rawinsonde observation taken on 07/29/2016 at 0600 MDT

Freezing level.................. 16836 ft MSL (11997 ft AGL)
Convective condensation level... 20428 ft MSL (15589 ft AGL)
Lifted condensation level....... 20885 ft MSL (16046 ft AGL)
Lifted index.................... -2.4
K index......................... +15.2

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  -63.8 -82.8   290   33   17  -4.0  -2.2   87.9 190.3    29.1      M    M
 45000  -59.8 -75.6   295   46   23   2.3   1.3   68.9 155.9    19.4      M    M
 40000  -53.3 -63.9   310   34   17   7.6   4.2   56.2 133.2    12.3      M    M
 38000  -49.0 -56.2   305   30   16   7.2   3.9   53.7 128.7    10.9      M    M
 36000  -44.7 -48.5   295   27   14   7.1   3.9   51.8 125.3     9.9      M    M
 34000  -40.3 -40.5   290   23   12   8.3   4.5   49.8 121.6     8.6      M    M
 32000  -34.7 -30.5   300   19   10   8.4   4.6   48.5 119.3     7.9      M    M
 30000  -29.6 -21.3   300   18    9   8.7   4.8   47.6 117.6     7.4      M    M
 29000  -27.2 -17.0   315   18    9   8.3   4.5   46.8 116.2     6.9      M    M
 28000  -25.9 -14.6   330   20   10   9.3   5.1   44.8 112.6     5.4      M    M
 27000  -23.4 -10.1   340   22   11   8.4   4.6   44.3 111.7     5.1      M    M
 26000  -21.1  -6.0   325   26   13   5.5   3.0   43.5 110.2     4.5      M    M
 25000  -19.3  -2.7   315   31   16   5.3   2.9   42.0 107.6     3.4      M    M
 24000  -18.6  -1.5   310   31   16  -0.1  -0.0   39.4 102.9     1.2      M    M
 23000  -17.0   1.4   300   31   16   7.3   4.0   37.8 100.1    -0.2   1820  9.2
 22000  -14.4   6.1   295   31   16   9.3   5.1   37.6  99.6    -0.4   1711  8.7
 21000  -11.6  11.1   300   30   15   9.3   5.1   37.4  99.2    -0.6   1598  8.1
 20000   -8.8  16.2   305   28   14   9.0   5.0   37.2  99.0    -0.7   1486  7.5
 19500   -7.7  18.1   310   32   16   4.2   2.3   36.9  98.4    -1.1   1437  7.3
 19000   -6.8  19.8   310   32   17  10.7   5.9   36.3  97.3    -1.7   1395  7.1
 18500   -5.3  22.5   310   32   16   9.9   5.4   36.3  97.3    -1.7   1336  6.8
 18000   -3.1  26.4   310   31   16   9.8   5.4   36.2  97.2    -1.7   1248  6.3
 17500   -1.6  29.1   305   30   15   9.8   5.4   36.3  97.3    -1.7   1189  6.0
 17000   -0.2  31.6   305   29   15   9.8   5.4   36.3  97.4    -1.7   1130  5.7
 16500    1.3  34.3   305   29   15   9.8   5.4   36.4  97.5    -1.7   1072  5.4
 16000    2.8  37.0   305   28   14   9.8   5.4   36.4  97.6    -1.6   1013  5.1
 15500    4.2  39.6   310   29   15   8.5   4.7   36.4  97.5    -1.7    956  4.9
 15000    5.3  41.5   310   29   15   8.0   4.4   36.1  96.9    -2.1    907  4.6
 14500    6.4  43.5   315   30   16   8.0   4.4   35.8  96.4    -2.4    858  4.4
 14000    7.7  45.9   315   31   16   8.8   4.8   35.6  96.0    -2.6    806  4.1
 13500    9.0  48.2   320   27   14   8.7   4.8   35.4  95.7    -2.8    752  3.8
 13000   10.3  50.5   325   24   12   8.8   4.8   35.2  95.4    -2.9    697  3.5
 12500   11.7  53.1   330   21   11   8.8   4.8   35.1  95.1    -3.1    642  3.3
 12000   12.9  55.2   340   19   10   6.1   3.3   34.8  94.7    -3.3    590  3.0
 11500   13.6  56.5   340   16    8   5.5   3.0   34.0  93.3    -4.1    554  2.8
 11000   14.8  58.6   345   14    7   9.2   5.0   33.7  92.7    -4.4    505  2.6
 10500   16.1  61.0   345   11    6   9.0   4.9   33.6  92.5    -4.5    450  2.3
 10250   16.8  62.2   345   10    5   9.0   4.9   33.5  92.4    -4.6    423  2.1
 10000   17.4  63.3   350    8    4   9.0   4.9   33.5  92.2    -4.7    395  2.0
  9750   18.1  64.6   350    7    4   9.0   4.9   33.4  92.1    -4.7    368  1.9
  9500   18.8  65.8   355    6    3   9.0   4.9   33.4  92.1    -4.8    340  1.7
  9250   19.4  66.9   005    4    2   9.0   4.9   33.3  92.0    -4.9    313  1.6
  9000   20.1  68.2   020    3    2   9.0   4.9   33.3  91.9    -4.9    286  1.5
  8750   20.8  69.4   025    3    2   9.0   4.9   33.2  91.8    -5.0    258  1.3
  8500   21.4  70.5   030    3    2   9.0   4.9   33.1  91.7    -5.1    231  1.2
  8250   22.1  71.8   035    4    2   9.0   4.9   33.1  91.6    -5.2    203  1.0
  8000   22.8  73.0   040    4    2   9.0   4.9   33.0  91.5    -5.2    176  0.9
  7750   23.4  74.1   045    4    2   9.0   5.0   33.0  91.3    -5.3    148  0.8
  7500   24.1  75.4   055    4    2   8.0   4.4   32.9  91.2    -5.4    122  0.6
  7250   24.6  76.3   060    5    2   7.2   3.9   32.7  90.9    -5.6     99  0.5
  7000   25.1  77.2   070    5    3   7.4   4.1   32.5  90.5    -5.9     75  0.4
  6750   25.7  78.3   070    4    2   7.3   4.0   32.3  90.2    -6.1     52  0.3
  6500   26.2  79.2   070    3    1   7.6   4.2   32.1  89.9    -6.3     29  0.1
  6250   26.7  80.1   070    2    1   6.5   3.5   32.0  89.5    -6.5      6  0.0
  6000   27.2  81.0   000    0    0   5.6   3.1   31.7  89.0    -6.8      M    M
  5750   27.6  81.7   110    1    1   4.2   2.3   31.3  88.4    -7.2      M    M
  5500   27.6  81.7   110    2    1  -4.0  -2.2   30.6  87.2    -7.9      M    M
  5250   26.7  80.1   110    4    2 -19.5 -10.7   29.1  84.3    -9.5      M    M
  5000   24.5  76.1   110    5    3 -39.5 -21.7   26.1  79.0   -12.5     37  0.2

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

           07/29/2016 at 0900 MDT          |       07/29/2016 at 1200 MDT
                                           |
K index... +16.4  LI... +273.4             | K index... +18.6  LI... +272.7
CAPE... +26.7  CIN... -12.3                | CAPE... +51.9  CIN... -28.7
                                           |
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 -62.9 -81.2  305  20 10   0.2   0.1 | -63.3 -81.9  310  20 10   0.2   0.1
 45000 -60.6 -77.1  305  29 15   4.3   2.4 | -60.8 -77.4  305  27 14   4.3   2.4
 40000 -53.4 -64.1  310  26 13   7.5   4.1 | -53.6 -64.5  320  25 13   7.5   4.1
 38000 -48.9 -56.0  315  24 12   7.5   4.1 | -49.2 -56.6  320  24 12   7.5   4.1
 36000 -44.4 -47.9  315  22 12   7.5   4.1 | -44.7 -48.5  320  22 11   7.6   4.2
 34000 -39.8 -39.6  315  21 11   7.7   4.2 | -39.8 -39.6  320  21 11   8.1   4.5
 32000 -35.2 -31.4  315  20 10   7.7   4.2 | -34.9 -30.8  320  19 10   8.2   4.5
 30000 -30.0 -22.0  320  21 11   7.7   4.2 | -29.8 -21.6  320  20 10   7.6   4.2
 29000 -27.7 -17.9  320  21 11   7.7   4.2 | -27.5 -17.5  315  20 10   7.6   4.2
 28000 -25.5 -13.9  320  22 11   6.2   3.4 | -25.3 -13.5  315  21 11   6.6   3.6
 27000 -23.6 -10.5  320  23 12   6.3   3.5 | -23.3  -9.9  315  22 11   6.7   3.7
 26000 -21.8  -7.2  315  25 13   6.3   3.5 | -21.3  -6.3  310  23 12   6.7   3.7
 25000 -19.9  -3.8  315  27 14   7.0   3.8 | -19.3  -2.7  310  25 13   7.1   3.9
 24000 -17.7   0.1  315  26 14   7.4   4.0 | -17.1   1.2  310  25 13   7.4   4.0
 23000 -15.5   4.1  310  26 14   7.4   4.0 | -14.9   5.2  305  25 13   7.4   4.1
 22000 -13.3   8.1  310  26 13   7.4   4.0 | -12.7   9.1  305  26 13   7.1   3.9
 21000 -11.1  12.0  315  26 13   7.4   4.1 | -10.7  12.7  310  25 13   7.1   3.9
 20000  -8.9  16.0  315  26 13   7.5   4.1 |  -8.6  16.5  315  25 13   7.2   3.9
 19500  -7.9  17.8  320  26 13   7.7   4.2 |  -7.6  18.3  315  25 13   7.6   4.2
 19000  -6.7  19.9  320  26 13   8.4   4.6 |  -6.4  20.5  315  25 13   8.6   4.7
 18500  -5.5  22.1  320  26 13   8.4   4.6 |  -5.1  22.8  315  25 13   8.6   4.7
 18000  -4.3  24.3  320  26 13   9.4   5.1 |  -3.9  25.0  315  25 13   8.8   4.8
 17500  -2.9  26.8  320  26 13   9.6   5.2 |  -2.6  27.3  315  25 13   8.9   4.9
 17000  -1.5  29.3  315  26 14   9.5   5.2 |  -1.4  29.5  315  26 13   9.0   5.0
 16500  -0.1  31.8  315  26 13   9.2   5.0 |  -0.0  32.0  315  26 13   9.2   5.0
 16000   1.2  34.2  315  26 13   9.2   5.0 |   1.3  34.3  315  26 13   9.2   5.0
 15500   2.6  36.7  315  25 13   9.5   5.2 |   2.7  36.9  315  25 13   9.9   5.4
 15000   4.0  39.2  315  24 13   9.5   5.2 |   4.1  39.4  315  25 13   9.9   5.4
 14500   5.4  41.7  320  24 12   9.4   5.2 |   5.6  42.1  315  24 13   9.6   5.3
 14000   7.4  45.3  320  23 12   9.4   5.1 |   7.7  45.9  315  23 12   9.5   5.2
 13500   8.8  47.8  325  22 11   9.5   5.2 |   9.0  48.2  315  21 11   8.6   4.7
 13000  10.2  50.4  325  22 11   9.5   5.2 |  10.3  50.5  320  19 10   8.6   4.7
 12500  11.6  52.9  330  21 11   9.1   5.0 |  11.6  52.9  320  17  9   9.1   5.0
 12000  13.0  55.4  330  20 10   9.0   4.9 |  13.0  55.4  325  15  8   9.2   5.1
 11500  14.4  57.9  335  19 10   7.7   4.2 |  14.4  57.9  325  13  7   8.8   4.8
 11000  15.5  59.9  335  17  9   7.1   3.9 |  15.7  60.3  330  12  6   8.6   4.7
 10500  16.6  61.9  340  15  8   4.3   2.4 |  16.9  62.4  330  11  6   5.6   3.1
 10250  16.9  62.4  340  14  7   5.8   3.2 |  17.3  63.1  335  10  5   7.0   3.8
 10000  17.5  63.5  345  13  7   8.9   4.9 |  18.1  64.6  335   9  4   9.2   5.1
  9750  18.1  64.6  350  11  6   8.2   4.5 |  18.8  65.8  340   8  4   9.0   4.9
  9500  18.8  65.8  355  10  5   7.2   3.9 |  19.4  66.9  345   6  3   6.6   3.6
  9250  19.2  66.6  355   9  5   7.2   4.0 |  19.9  67.8  350   5  2   5.6   3.1
  9000  19.8  67.6  005   8  4   8.8   4.8 |  20.4  68.7  355   4  2   7.1   3.9
  8750  20.5  68.9  010   7  4   8.6   4.7 |  20.9  69.6  005   2  1   6.8   3.7
  8500  21.0  69.8  020   6  3   6.5   3.6 |  21.4  70.5  025   1  1   6.8   3.7
  8250  21.4  70.5  025   5  3   4.8   2.7 |  21.9  71.4  060   1  0   6.9   3.8
  8000  21.8  71.2  035   5  2   4.9   2.7 |  22.4  72.3  105   1  0   7.6   4.2
  7750  22.1  71.8  050   4  2   4.0   2.2 |  22.9  73.2  130   1  0   8.3   4.5
  7500  22.3  72.1  065   4  2   2.2   1.2 |  23.5  74.3  145   1  0   9.0   4.9
  7250  22.5  72.5  080   4  2   1.8   1.0 |  24.2  75.6  155   1  1   9.3   5.1
  7000  22.6  72.7  100   4  2   0.6   0.3 |  24.9  76.8  160   1  1   9.3   5.1
  6750  22.6  72.7  120   4  2   0.4   0.2 |  25.6  78.1  165   1  1  10.2   5.6
  6500  22.6  72.7  130   4  2   1.9   1.1 |  26.4  79.5  170   1  1  11.0   6.0
  6250  22.7  72.9  135   5  2   2.6   1.4 |  27.2  81.0  170   1  1  11.4   6.3
  6000  22.9  73.2  140   5  3   0.4   0.2 |  28.0  82.4  175   1  1   9.9   5.4
  5750  22.8  73.0  145   5  2   5.0   2.7 |  28.8  83.8  185   1  1  12.3   6.7
  5500  23.6  74.5  140   5  2  12.0   6.6 |  29.9  85.8  185   1  1  16.2   8.9
  5250  24.3  75.7  140   5  2   6.5   3.6 |  31.0  87.8  185   1  0  13.1   7.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/29/2016 at 1500 MDT          |       07/29/2016 at 1800 MDT
                                           |
K index... +17.9  LI... +274.1             | K index... +19.5  LI... +273.6
CAPE... +19.2  CIN... -28.8                | CAPE... +6.8  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 -62.9 -81.2  315  18  9  -0.4  -0.2 | -63.2 -81.8  335  13  7   0.2   0.1
 45000 -61.1 -78.0  310  29 15   4.4   2.4 | -60.6 -77.1  325  20 10   4.6   2.5
 40000 -53.8 -64.8  315  30 15   7.3   4.0 | -53.2 -63.8  315  23 12   7.0   3.8
 38000 -49.4 -56.9  315  28 14   7.3   4.0 | -49.0 -56.2  310  26 13   7.0   3.8
 36000 -45.0 -49.0  315  26 13   7.5   4.1 | -44.8 -48.6  310  29 15   7.3   4.0
 34000 -40.1 -40.2  315  25 13   8.3   4.5 | -39.8 -39.6  310  28 15   8.4   4.6
 32000 -35.1 -31.2  310  23 12   8.3   4.5 | -34.1 -29.4  305  28 14   8.6   4.7
 30000 -29.8 -21.6  310  22 11   7.9   4.3 | -29.3 -20.7  305  26 13   8.0   4.4
 29000 -27.4 -17.3  310  22 11   7.9   4.3 | -26.9 -16.4  305  25 13   8.0   4.4
 28000 -25.2 -13.4  310  22 11   6.5   3.6 | -24.6 -12.3  305  24 12   7.0   3.8
 27000 -23.2  -9.8  305  22 11   6.6   3.6 | -22.5  -8.5  305  23 12   7.1   3.9
 26000 -21.2  -6.2  305  22 11   6.6   3.6 | -20.4  -4.7  305  23 12   7.1   3.9
 25000 -19.2  -2.6  305  23 12   7.3   4.0 | -18.2  -0.8  305  23 12   6.9   3.8
 24000 -16.9   1.6  305  24 12   7.7   4.2 | -16.2   2.8  310  23 12   6.8   3.7
 23000 -14.6   5.7  305  25 13   7.7   4.2 | -14.2   6.4  315  23 12   6.8   3.7
 22000 -12.3   9.9  305  26 13   7.8   4.3 | -12.2  10.0  320  23 12   7.6   4.2
 21000 -10.0  14.0  305  26 13   7.8   4.3 |  -9.9  14.2  320  23 12   7.9   4.3
 20000  -7.7  18.1  310  26 13   7.9   4.3 |  -7.6  18.3  325  22 12   7.9   4.4
 19500  -6.6  20.1  315  26 13   8.1   4.4 |  -6.4  20.5  325  22 11   8.1   4.5
 19000  -5.3  22.5  315  25 13   8.6   4.7 |  -5.1  22.8  330  22 11   8.8   4.8
 18500  -4.1  24.6  315  25 13   8.6   4.7 |  -3.9  25.0  330  21 11   8.8   4.8
 18000  -2.8  27.0  315  24 13   9.2   5.1 |  -2.5  27.5  330  20 10   9.2   5.0
 17500  -1.4  29.5  320  23 12   9.4   5.1 |  -1.2  29.8  335  19 10   9.3   5.1
 17000  -0.0  32.0  320  22 12   9.2   5.1 |   0.2  32.4  335  18 10   9.3   5.1
 16500   1.3  34.3  320  21 11   8.6   4.7 |   1.6  34.9  335  18  9   9.2   5.0
 16000   2.5  36.5  320  20 10   8.6   4.7 |   2.9  37.2  335  17  9   9.2   5.0
 15500   3.8  38.8  320  18  9   8.8   4.8 |   4.3  39.7  340  16  8   9.2   5.1
 15000   5.0  41.0  320  17  9   8.8   4.8 |   6.3  43.3  340  14  7   9.2   5.1
 14500   7.0  44.6  325  16  8   8.9   4.9 |   7.7  45.9  340  14  7   9.5   5.2
 14000   8.3  46.9  325  15  8   8.9   4.9 |   9.1  48.4  340  13  7   9.5   5.2
 13500   9.6  49.3  325  14  7   8.9   4.9 |  10.5  50.9  335  12  6   9.4   5.1
 13000  10.9  51.6  325  14  7   8.9   4.9 |  11.9  53.4  335  11  6   9.3   5.1
 12500  12.2  54.0  325  13  7   9.1   5.0 |  13.2  55.8  335  10  5   9.2   5.1
 12000  13.5  56.3  320  12  6   9.2   5.0 |  14.6  58.3  335  10  5   9.1   5.0
 11500  14.9  58.8  320  11  6   9.3   5.1 |  16.0  60.8  330   9  5   8.5   4.7
 11000  16.3  61.3  320  10  5   9.4   5.1 |  17.1  62.8  330   8  4   8.1   4.4
 10500  17.6  63.7  315   9  5   6.0   3.3 |  18.3  64.9  325   8  4  11.4   6.3
 10250  18.0  64.4  315   8  4   7.9   4.3 |  19.3  66.7  325   7  4  12.1   6.7
 10000  18.8  65.8  315   8  4  10.9   6.0 |  20.0  68.0  320   7  3   7.9   4.3
  9750  19.6  67.3  310   7  4  10.7   5.8 |  20.6  69.1  320   6  3   9.4   5.1
  9500  20.3  68.5  310   6  3   8.5   4.6 |  21.3  70.3  315   6  3   7.7   4.2
  9250  20.8  69.4  310   6  3   7.7   4.2 |  21.8  71.2  310   6  3   7.8   4.3
  9000  21.5  70.7  310   5  3   9.6   5.3 |  22.5  72.5  305   5  3   9.1   5.0
  8750  22.2  72.0  305   4  2   9.1   5.0 |  23.1  73.6  300   5  3   8.7   4.8
  8500  22.9  73.2  305   4  2   9.5   5.2 |  23.8  74.8  295   5  3   9.0   4.9
  8250  23.6  74.5  305   4  2   9.5   5.2 |  24.4  75.9  290   5  2   8.8   4.8
  8000  24.3  75.7  300   3  2   8.9   4.9 |  25.1  77.2  285   5  2   8.2   4.5
  7750  25.0  77.0  300   3  2   8.8   4.8 |  25.7  78.3  280   5  2   7.8   4.3
  7500  25.7  78.3  300   3  2   9.9   5.4 |  26.3  79.3  275   4  2   8.8   4.9
  7250  26.4  79.5  295   3  2  10.6   5.8 |  27.0  80.6  275   4  2   9.6   5.3
  7000  27.2  81.0  290   3  2   9.9   5.4 |  27.7  81.9  275   4  2   9.6   5.3
  6750  27.9  82.2  290   3  2   9.9   5.4 |  28.4  83.1  270   4  2  10.1   5.5
  6500  28.7  83.7  285   3  2  10.9   6.0 |  29.1  84.4  270   4  2  10.5   5.7
  6250  29.5  85.1  285   3  2  11.4   6.2 |  29.9  85.8  265   4  2  11.1   6.1
  6000  30.4  86.7  280   3  1  10.4   5.7 |  30.7  87.3  265   4  2   9.9   5.4
  5750  31.1  88.0  280   3  1  12.8   7.0 |  31.5  88.7  265   4  2   9.3   5.1
  5500  32.3  90.1  285   3  1  16.2   8.9 |  32.2  90.0  265   4  2  10.9   6.0
  5250  33.4  92.1  285   3  1  13.9   7.7 |  33.1  91.6  270   4  2  11.1   6.1
  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 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  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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