Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 311224
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0624 MDT Thursday, July 31, 2014

This forecast is for Thursday, July 31, 2014:

If the trigger temperature of 75.8 F/24.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1044 ft/min (5.3 m/s)
   Maximum height of thermals.................. 15317 ft MSL (10478 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 0945 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11158 ft MSL (6318 ft AGL)
Thermal soaring outlook for Friday 08/01....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:13:47 / 20:27:31 MDT
Total possible sunshine........... 14 hr 13 min 43 sec (853 min 43 sec)
Altitude of sun at 13:20:26 MDT... 69.00 degrees

Upper air data from rawinsonde observation taken on 07/31/2014 at 0600 MDT

Freezing level.................. 15136 ft MSL (10297 ft AGL)
Convective condensation level... 12587 ft MSL (7748 ft AGL)
Lifted condensation level....... 13464 ft MSL (8625 ft AGL)
Lifted index.................... -2.5
K index......................... +26.5

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  -65.7 -86.3   295   21   11  -1.0  -0.5   84.7 184.5    31.1      M    M
 45000  -61.0 -77.8   275   44   23   5.6   3.1   68.2 154.8    23.1      M    M
 40000  -53.2 -63.8   265   62   32   8.6   4.7   56.4 133.6    16.9      M    M
 38000  -48.0 -54.4   265   54   28   7.4   4.1   55.5 131.9    16.7      M    M
 36000  -44.1 -47.4   270   46   24   6.7   3.7   52.7 126.9    15.2      M    M
 34000  -39.1 -38.4   275   39   20   8.8   4.8   51.7 125.0    14.8      M    M
 32000  -34.2 -29.6   285   33   17   7.6   4.2   50.3 122.6    14.2      M    M
 30000  -28.6 -19.5   290   26   14   8.0   4.4   49.2 120.5    13.7      M    M
 29000  -26.3 -15.3   285   29   15   7.1   3.9   48.3 118.9    13.2      M    M
 28000  -24.2 -11.6   280   31   16   8.6   4.7   47.3 117.2    12.6      M    M
 27000  -21.5  -6.7   280   29   15   9.0   4.9   47.0 116.7    12.5      M    M
 26000  -19.0  -2.2   280   26   14   7.7   4.2   46.5 115.7    12.2      M    M
 25000  -17.5   0.5   280   24   12   3.7   2.0   44.8 112.6    10.9      M    M
 24000  -15.8   3.6   285   25   13   9.0   4.9   43.3 110.0     9.8      M    M
 23000  -13.2   8.2   290   27   14   8.6   4.7   42.9 109.2     9.5      M    M
 22000  -11.4  11.5   295   29   15   5.0   2.7   41.6 106.9     8.6      M    M
 21000   -9.9  14.2   290   29   15   4.2   2.3   39.9 103.9     7.2      M    M
 20000   -7.6  18.3   285   30   15   8.7   4.7   39.0 102.2     6.7      M    M
 19500   -6.3  20.7   290   26   13   9.1   5.0   38.8 101.9     6.5      M    M
 19000   -5.2  22.6   290   24   12   6.5   3.6   38.5 101.2     6.2      M    M
 18500   -4.2  24.4   295   23   12   6.8   3.7   37.9 100.3     5.8      M    M
 18000   -3.1  26.4   295   22   11   8.8   4.8   37.6  99.6     5.5      M    M
 17500   -2.4  27.7   290   21   11   0.8   0.5   36.7  98.0     4.7      M    M
 17000   -2.3  27.9   285   19   10   3.0   1.6   35.3  95.6     3.4      M    M
 16500   -1.4  29.5   275   17    9   4.8   2.6   34.0  93.1     2.1      M    M
 16000   -0.9  30.4   270   16    8   1.3   0.7   33.0  91.4     1.2      M    M
 15500   -0.5  31.1   285   14    7   7.0   3.8   32.0  89.6     0.1      M    M
 15000    0.6  33.1   295   13    7   9.4   5.2   31.7  89.1    -0.3    803  4.1
 14500    1.9  35.4   290   12    6   6.8   3.7   31.5  88.8    -0.5    751  3.8
 14000    2.5  36.5   285   11    6   6.5   3.6   30.8  87.4    -1.3    717  3.6
 13500    3.7  38.7   280   11    6   8.7   4.8   30.5  86.9    -1.6    667  3.4
 13000    5.0  41.0   270   11    6   8.7   4.8   30.3  86.6    -1.8    613  3.1
 12500    6.3  43.3   265   11    6   8.7   4.8   30.2  86.3    -1.9    560  2.8
 12000    7.5  45.5   260   11    6   8.8   4.8   30.0  86.1    -2.1    507  2.6
 11500    8.7  47.7   255    7    4   5.5   3.0   29.7  85.5    -2.4    458  2.3
 11000    9.2  48.6   240    4    2   4.4   2.4   28.8  83.9    -3.3    427  2.2
 10500    9.7  49.5   180    2    1   4.7   2.6   28.0  82.4    -4.3    396  2.0
 10250   10.1  50.2   160    2    1   5.3   2.9   27.6  81.7    -4.7    379  1.9
 10000   10.5  50.9   140    1    1   5.4   2.9   27.3  81.1    -5.0    360  1.8
  9750   10.8  51.4   060    2    1   5.3   2.9   26.9  80.5    -5.4    342  1.7
  9500   11.2  52.2   045    3    2   5.6   3.1   26.6  79.9    -5.8    324  1.6
  9250   11.6  52.9   040    5    3   6.6   3.6   26.3  79.4    -6.1    304  1.5
  9000   12.1  53.8   035    7    4   7.0   3.9   26.1  79.0    -6.3    281  1.4
  8750   12.6  54.7   035    7    3   6.9   3.8   25.9  78.6    -6.6    259  1.3
  8500   13.1  55.6   030    6    3   6.9   3.8   25.7  78.2    -6.8    236  1.2
  8250   13.6  56.5   030    6    3   6.9   3.8   25.5  77.8    -7.0    214  1.1
  8000   14.1  57.4   025    5    3   6.9   3.8   25.3  77.5    -7.3    192  1.0
  7750   14.6  58.3   035    5    3   6.9   3.8   25.0  77.1    -7.5    169  0.9
  7500   15.1  59.2   045    6    3   6.9   3.8   24.8  76.7    -7.8    147  0.7
  7250   15.6  60.1   050    6    3   6.9   3.8   24.6  76.3    -8.0    124  0.6
  7000   16.1  61.0   060    7    4   6.9   3.8   24.4  75.9    -8.2    102  0.5
  6750   16.6  61.9   060    6    3   6.9   3.8   24.2  75.5    -8.5     80  0.4
  6500   17.1  62.8   055    5    3   6.9   3.8   24.0  75.1    -8.7     57  0.3
  6250   17.6  63.7   055    4    2   7.0   3.8   23.7  74.7    -9.0     35  0.2
  6000   18.1  64.6   050    3    2   6.9   3.8   23.5  74.4    -9.2     12  0.1
  5750   18.6  65.5   050    3    2   7.3   4.0   23.3  74.0    -9.5      M    M
  5500   19.1  66.4   050    3    2   5.8   3.2   23.1  73.6    -9.7      M    M
  5250   19.5  67.1   055    3    2   3.8   2.1   22.7  72.9   -10.2      M    M
  5000   19.6  67.3   055    3    2  -2.5  -1.4   22.1  71.8   -10.8      M    M

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

           07/31/2014 at 0900 MDT          |       07/31/2014 at 1200 MDT
                                           |
K index... +26.0  LI... -0.8               | K index... +25.2  LI... -1.4
CAPE... +65.5  CIN... -69.9                | CAPE... +263.9  CIN... -11.3
                                           |
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 -63.4 -82.1  290  25 13   1.9   1.1 | -63.7 -82.7  285  26 13   1.6   0.9
 45000 -59.6 -75.3  280  49 25   3.7   2.1 | -60.1 -76.2  275  50 26   4.0   2.2
 40000 -52.9 -63.2  275  61 32   7.4   4.0 | -53.0 -63.4  265  62 32   7.6   4.2
 38000 -48.4 -55.1  275  51 26   7.4   4.0 | -48.5 -55.3  265  50 26   7.6   4.2
 36000 -44.0 -47.2  280  41 21   7.6   4.2 | -43.9 -47.0  270  39 20   7.8   4.3
 34000 -39.1 -38.4  285  36 19   8.2   4.5 | -38.9 -38.0  270  35 18   8.3   4.6
 32000 -34.2 -29.6  290  32 17   8.8   4.8 | -34.0 -29.2  270  31 16   8.2   4.5
 30000 -29.4 -20.9  295  26 13   8.0   4.4 | -29.3 -20.7  275  26 13   7.7   4.2
 29000 -27.0 -16.6  300  23 12   8.0   4.4 | -27.0 -16.6  275  23 12   7.7   4.2
 28000 -24.6 -12.3  300  20 10   7.5   4.1 | -24.2 -11.6  280  20 10   7.8   4.3
 27000 -22.4  -8.3  300  20 10   7.4   4.0 | -21.9  -7.4  280  20 10   7.8   4.3
 26000 -20.2  -4.4  300  20 10   7.4   4.0 | -19.5  -3.1  280  19 10   7.8   4.3
 25000 -18.0  -0.4  300  20 10   7.3   4.0 | -17.2   1.0  285  19 10   7.3   4.0
 24000 -16.0   3.2  300  20 10   6.7   3.7 | -15.2   4.6  290  18 10   6.8   3.7
 23000 -13.9   7.0  300  20 10   6.7   3.7 | -13.2   8.2  295  18  9   6.8   3.7
 22000 -11.4  11.5  300  20 10   6.2   3.4 | -11.1  12.0  300  17  9   6.3   3.5
 21000  -9.6  14.7  295  18  9   6.2   3.4 |  -9.4  15.1  300  17  9   5.9   3.2
 20000  -7.9  17.8  290  17  9   6.3   3.4 |  -7.6  18.3  300  16  8   5.9   3.2
 19500  -7.0  19.4  290  17  9   6.1   3.3 |  -6.7  19.9  300  16  8   5.9   3.2
 19000  -6.2  20.8  285  17  9   5.6   3.1 |  -5.9  21.4  300  16  8   5.9   3.2
 18500  -5.4  22.3  285  17  9   5.6   3.1 |  -5.0  23.0  300  16  8   5.9   3.2
 18000  -4.6  23.7  280  17  9   5.9   3.2 |  -4.2  24.4  295  16  8   5.8   3.2
 17500  -3.7  25.3  280  17  9   5.9   3.3 |  -3.4  25.9  295  16  8   5.8   3.2
 17000  -2.9  26.8  280  17  9   6.1   3.3 |  -2.6  27.3  295  16  8   5.8   3.2
 16500  -2.0  28.4  280  16  8   6.4   3.5 |  -1.8  28.8  295  16  8   6.0   3.3
 16000  -1.1  30.0  275  16  8   6.4   3.5 |  -0.9  30.4  290  15  8   6.0   3.3
 15500  -0.1  31.8  275  15  8   6.5   3.6 |  -0.1  31.8  290  15  8   6.2   3.4
 15000   0.8  33.4  275  14  7   6.5   3.6 |   0.8  33.4  290  14  7   6.3   3.4
 14500   1.7  35.1  270  13  6   6.7   3.7 |   1.7  35.1  285  13  7   6.3   3.5
 14000   2.7  36.9  270  11  6   6.7   3.7 |   2.6  36.7  285  12  6   6.3   3.5
 13500   3.6  38.5  270  10  5   6.9   3.8 |   3.9  39.0  280  10  5   6.8   3.7
 13000   4.6  40.3  270   9  5   7.0   3.8 |   4.9  40.8  280   9  5   6.9   3.8
 12500   5.6  42.1  265   8  4   7.3   4.0 |   5.9  42.6  280   8  4   7.2   4.0
 12000   6.7  44.1  270   7  4   7.8   4.3 |   6.9  44.4  280   7  4   7.4   4.1
 11500   7.8  46.0  270   7  3   7.7   4.2 |   8.0  46.4  285   7  3   7.6   4.2
 11000   8.9  48.0  275   6  3   7.4   4.0 |   9.1  48.4  285   5  3   7.6   4.2
 10500  10.0  50.0  280   5  2   4.4   2.4 |  10.1  50.2  285   4  2   3.9   2.1
 10250  10.1  50.2  285   4  2   3.8   2.1 |  10.3  50.5  285   3  2   5.6   3.1
 10000  10.7  51.3  285   3  2   9.1   5.0 |  11.0  51.8  290   2  1  10.8   5.9
  9750  11.3  52.3  290   3  1   9.8   5.4 |  11.7  53.1  295   2  1   9.6   5.2
  9500  12.0  53.6  295   2  1   8.1   4.5 |  12.3  54.1  310   1  1   8.1   4.4
  9250  12.4  54.3  305   2  1   5.6   3.0 |  12.8  55.0  320   1  0   7.4   4.1
  9000  12.9  55.2  315   1  1   7.4   4.0 |  13.4  56.1  340   1  0   9.1   5.0
  8750  13.5  56.3  345   1  0   9.5   5.2 |  14.1  57.4  005   1  0   9.2   5.1
  8500  14.1  57.4  025   1  1   7.5   4.1 |  14.7  58.5  020   1  0   9.0   4.9
  8250  14.6  58.3  040   1  1   6.1   3.3 |  15.3  59.5  015   1  0   8.8   4.8
  8000  15.1  59.2  050   2  1   6.5   3.6 |  16.0  60.8  015   1  0   9.7   5.3
  7750  15.5  59.9  050   2  1   6.5   3.5 |  16.8  62.2  015   1  0  10.3   5.7
  7500  16.0  60.8  055   3  1   5.6   3.1 |  17.5  63.5  015   1  0  10.0   5.5
  7250  16.4  61.5  065   3  1   4.8   2.7 |  18.3  64.9  015   1  0  10.0   5.5
  7000  16.7  62.1  075   3  1   5.3   2.9 |  19.0  66.2  015   1  0  10.3   5.6
  6750  17.1  62.8  085   3  1   6.8   3.7 |  19.8  67.6  010   1  0  10.7   5.9
  6500  17.7  63.9  090   3  1   7.6   4.2 |  20.6  69.1  005   1  0  10.8   5.9
  6250  18.2  64.8  095   2  1   7.2   4.0 |  21.4  70.5  000   0  0  10.8   6.0
  6000  18.7  65.7  100   2  1   7.3   4.0 |  22.2  72.0  000   0  0  10.6   5.8
  5750  19.4  66.9  100   3  1  12.7   6.9 |  23.0  73.4  340   1  0  13.1   7.2
  5500  20.6  69.1  100   2  1  21.5  11.8 |  24.1  75.4  345   1  0  15.6   8.6
  5250     M     M    M   M  M     M     M |  25.2  77.4  350   1  0  13.7   7.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/31/2014 at 1500 MDT          |       07/31/2014 at 1800 MDT
                                           |
K index... +25.7  LI... -1.6               | K index... +25.0  LI... -1.6
CAPE... +160.8  CIN... -14.4               | CAPE... +101.7  CIN... -31.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.5 -82.3  275  27 14   2.4   1.3 | -64.0 -83.2  275  30 15   3.3   1.8
 45000 -59.2 -74.6  275  49 25   3.4   1.9 | -59.1 -74.4  275  48 25   3.1   1.7
 40000 -53.0 -63.4  265  60 31   8.1   4.4 | -53.1 -63.6  265  53 27   8.2   4.5
 38000 -48.2 -54.8  265  53 27   8.0   4.4 | -48.2 -54.8  260  47 24   8.1   4.5
 36000 -43.3 -45.9  265  46 24   8.1   4.4 | -43.3 -45.9  260  41 21   8.2   4.5
 34000 -38.5 -37.3  260  41 21   8.1   4.4 | -38.4 -37.1  260  37 19   8.2   4.5
 32000 -33.6 -28.5  260  36 19   7.9   4.4 | -33.5 -28.3  265  34 18   8.1   4.4
 30000 -29.1 -20.4  265  32 16   7.5   4.1 | -29.0 -20.2  270  31 16   7.5   4.1
 29000 -26.3 -15.3  270  29 15   7.5   4.1 | -26.7 -16.1  275  29 15   7.5   4.1
 28000 -24.1 -11.4  275  27 14   7.3   4.0 | -24.0 -11.2  280  28 14   7.0   3.8
 27000 -21.9  -7.4  275  25 13   7.4   4.0 | -21.9  -7.4  285  26 13   7.1   3.9
 26000 -19.8  -3.6  280  23 12   7.4   4.0 | -19.8  -3.6  285  24 12   7.1   3.9
 25000 -17.6   0.3  280  21 11   7.1   3.9 | -17.8  -0.0  290  22 11   6.9   3.8
 24000 -15.6   3.9  285  19 10   6.8   3.7 | -15.8   3.6  290  20 10   6.6   3.6
 23000 -13.6   7.5  290  16  8   6.8   3.7 | -13.9   7.0  290  18  9   6.6   3.6
 22000 -11.6  11.1  295  14  7   6.3   3.5 | -12.0  10.4  290  15  8   6.3   3.4
 21000  -9.9  14.2  300  14  7   5.9   3.2 | -10.2  13.6  295  13  7   6.0   3.3
 20000  -8.1  17.4  305  14  7   5.9   3.2 |  -8.4  16.9  305  10  5   6.0   3.3
 19500  -7.2  19.0  305  14  7   5.9   3.2 |  -7.6  18.3  310   9  5   6.0   3.3
 19000  -6.4  20.5  305  14  7   6.2   3.4 |  -6.6  20.1  320   9  4   6.8   3.7
 18500  -5.5  22.1  310  14  7   6.2   3.4 |  -5.6  21.9  325   8  4   6.8   3.7
 18000  -4.6  23.7  310  13  7   6.2   3.4 |  -4.6  23.7  330   8  4   6.8   3.8
 17500  -3.7  25.3  310  13  7   6.2   3.4 |  -3.6  25.5  330   8  4   6.9   3.8
 17000  -2.8  27.0  310  13  7   6.2   3.4 |  -2.6  27.3  335   7  4   6.9   3.8
 16500  -1.8  28.8  310  13  7   6.4   3.5 |  -1.6  29.1  335   7  4   5.8   3.2
 16000  -0.9  30.4  310  12  6   6.4   3.5 |  -0.8  30.6  335   6  3   5.9   3.2
 15500   0.0  32.0  310  12  6   6.5   3.6 |   0.1  32.2  340   6  3   6.5   3.6
 15000   0.9  33.6  310  11  6   6.5   3.6 |   1.1  34.0  340   6  3   6.6   3.6
 14500   1.9  35.4  305  10  5   6.6   3.6 |   2.1  35.8  340   5  3   6.9   3.8
 14000   3.3  37.9  305   9  5   6.7   3.7 |   3.1  37.6  340   4  2   7.2   3.9
 13500   4.3  39.7  300   8  4   7.1   3.9 |   4.7  40.5  335   4  2   7.6   4.2
 13000   5.3  41.5  300   8  4   7.2   4.0 |   5.8  42.4  335   3  2   7.7   4.2
 12500   6.4  43.5  295   8  4   7.2   4.0 |   6.9  44.4  330   3  2   7.2   4.0
 12000   7.4  45.3  295   6  3   7.3   4.0 |   7.9  46.2  320   3  1   7.0   3.8
 11500   8.4  47.1  290   5  3   8.0   4.4 |   8.9  48.0  315   3  1   7.9   4.4
 11000   9.6  49.3  290   4  2   8.4   4.6 |  10.1  50.2  300   3  1   8.5   4.7
 10500  10.7  51.3  285   4  2   4.1   2.3 |  11.3  52.3  285   3  2   4.6   2.5
 10250  10.9  51.6  285   3  2   5.9   3.2 |  11.5  52.7  285   3  1   6.1   3.3
 10000  11.6  52.9  290   3  1  11.5   6.3 |  12.3  54.1  280   3  1  11.8   6.5
  9750  12.4  54.3  295   2  1  10.3   5.6 |  13.0  55.4  280   3  1  10.8   5.9
  9500  13.1  55.6  300   2  1   8.5   4.7 |  13.8  56.8  280   2  1   7.7   4.2
  9250  13.6  56.5  300   2  1   8.2   4.5 |  14.2  57.6  280   2  1   6.5   3.6
  9000  14.3  57.7  300   2  1  10.5   5.8 |  14.8  58.6  280   2  1   9.7   5.3
  8750  15.1  59.2  305   2  1  10.5   5.8 |  15.5  59.9  280   2  1   9.6   5.3
  8500  15.9  60.6  305   2  1  10.2   5.6 |  16.2  61.2  280   2  1   9.2   5.1
  8250  16.6  61.9  305   2  1  10.1   5.5 |  16.8  62.2  275   2  1   8.9   4.9
  8000  17.3  63.1  305   2  1   9.7   5.3 |  17.5  63.5  275   2  1   9.5   5.2
  7750  18.1  64.6  310   2  1   9.6   5.3 |  18.2  64.8  270   2  1   9.8   5.4
  7500  18.8  65.8  305   2  1  10.2   5.6 |  18.9  66.0  270   2  1   9.6   5.2
  7250  19.6  67.3  305   1  1  10.3   5.6 |  19.6  67.3  265   2  1   9.4   5.2
  7000  20.3  68.5  300   1  1  10.5   5.8 |  20.3  68.5  260   2  1   9.8   5.4
  6750  21.1  70.0  300   1  1  11.1   6.1 |  21.1  70.0  260   2  1  10.5   5.8
  6500  21.9  71.4  300   1  1  11.1   6.1 |  21.9  71.4  260   2  1  10.6   5.8
  6250  22.8  73.0  300   1  1  11.7   6.4 |  22.7  72.9  260   2  1  10.7   5.9
  6000  23.6  74.5  300   1  1   9.4   5.1 |  23.5  74.3  260   2  1  10.4   5.7
  5750  24.3  75.7  300   1  1  11.7   6.4 |  24.2  75.6  260   2  1  10.2   5.6
  5500  25.4  77.7  305   1  1  16.8   9.2 |  24.9  76.8  260   2  1  10.5   5.8
  5250  26.5  79.7  310   1  1  12.8   7.0 |  25.7  78.3  265   2  1  10.3   5.6
  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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