Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 291238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0635 MDT Friday, May 29, 2015

This forecast is for Friday, May 29, 2015:

If the trigger temperature of 62.3 F/16.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 773 ft/min (3.9 m/s)
   Maximum height of thermals.................. 14882 ft MSL (10043 ft AGL)

Forecast maximum temperature................... 76.0 F/24.9 C
Time of trigger temperature.................... 1030 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................. 13195 ft MSL (8356 ft AGL)
Thermal soaring outlook for Saturday 05/30..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:51:39 / 20:31:15 MDT
Total possible sunshine........... 14 hr 39 min 36 sec (879 min 36 sec)
Altitude of sun at 13:11:38 MDT... 72.52 degrees

Upper air data from rawinsonde observation taken on 05/29/2015 at 0600 MDT

Freezing level.................. 11059 ft MSL (6220 ft AGL)
Convective condensation level... 12283 ft MSL (7444 ft AGL)
Lifted condensation level....... 14246 ft MSL (9407 ft AGL)
Lifted index.................... -2.4
K index......................... +14.0

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  -59.5 -75.1   305   22   11   7.5   4.1  100.1 212.1    43.3      M    M
 45000  -56.4 -69.5   275   34   18   4.9   2.7   80.6 177.1    34.4      M    M
 40000  -55.8 -68.4   280   54   28   2.5   1.4   58.6 137.5    22.4      M    M
 38000  -55.0 -67.0   285   60   31   3.5   1.9   49.5 121.1    16.9      M    M
 36000  -52.7 -62.9   285   64   33   6.3   3.4   44.6 112.3    14.0      M    M
 34000  -49.1 -56.4   290   57   30   2.0   1.1   41.4 106.5    12.1      M    M
 32000  -45.8 -50.4   290   54   28   7.0   3.8   37.7  99.9     9.7      M    M
 30000  -41.5 -42.7   290   50   26   7.6   4.2   35.9  96.6     8.6      M    M
 29000  -39.2 -38.6   290   46   24   7.6   4.2   34.9  94.8     7.9      M    M
 28000  -36.9 -34.4   290   42   22   7.6   4.2   34.0  93.2     7.4      M    M
 27000  -34.6 -30.3   290   38   20   8.4   4.6   33.3  92.0     6.9      M    M
 26000  -32.0 -25.6   290   34   18   8.5   4.7   32.8  91.1     6.6      M    M
 25000  -29.4 -20.9   290   30   16   8.6   4.7   32.4  90.4     6.4      M    M
 24000  -26.9 -16.4   295   28   14   8.1   4.4   32.0  89.5     6.1      M    M
 23000  -24.5 -12.1   295   28   15   8.2   4.5   31.2  88.2     5.5      M    M
 22000  -22.0  -7.6   295   28   15   8.2   4.5   30.6  87.0     5.1      M    M
 21000  -19.6  -3.3   300   29   15   8.2   4.5   30.0  86.1     4.7      M    M
 20000  -16.5   2.3   300   29   15   7.7   4.2   29.5  85.1     4.3      M    M
 19500  -15.4   4.3   300   28   15   7.5   4.1   29.1  84.3     3.9      M    M
 19000  -14.3   6.3   300   28   14   6.8   3.8   28.7  83.6     3.6      M    M
 18500  -13.4   7.9   300   27   14   6.3   3.4   28.0  82.4     3.0      M    M
 18000  -12.5   9.5   300   27   14   6.3   3.4   27.4  81.3     2.5      M    M
 17500  -11.5  11.3   300   26   14   6.2   3.4   26.8  80.3     2.0      M    M
 17000  -10.5  13.1   300   26   13   7.8   4.3   26.3  79.4     1.5      M    M
 16500   -9.4  15.1   300   25   13   8.0   4.4   26.0  78.9     1.2      M    M
 16000   -8.2  17.2   300   25   13   8.0   4.4   25.8  78.4     1.0      M    M
 15500   -7.0  19.4   305   26   13   8.0   4.4   25.4  77.8     0.7      M    M
 15000   -6.1  21.0   305   27   14   4.4   2.4   24.8  76.7     0.1      M    M
 14500   -5.4  22.3   310   23   12   5.4   3.0   24.0  75.2    -0.6    741  3.8
 14000   -4.6  23.7   315   20   10   3.1   1.7   23.2  73.7    -1.3    704  3.6
 13500   -4.2  24.4   305   18    9   3.7   2.0   22.1  71.7    -2.4    677  3.4
 13000   -3.8  25.2   295   16    8   3.4   1.9   21.1  69.9    -3.5    649  3.3
 12500   -3.1  26.4   305   15    8   8.2   4.5   20.4  68.7    -4.2    613  3.1
 12000   -1.9  28.6   315   14    7   8.6   4.7   20.2  68.3    -4.5    562  2.9
 11500   -0.8  30.6   315   11    6   5.0   2.7   19.8  67.7    -5.0    516  2.6
 11000    0.2  32.4   315    8    4  10.1   5.5   19.4  66.9    -5.5    472  2.4
 10500    1.5  34.7   320    4    2  10.6   5.8   19.3  66.8    -5.6    415  2.1
 10250    2.2  36.0   325    3    2   3.8   2.1   19.3  66.7    -5.7    388  2.0
 10000    2.2  36.0   005    1    1   0.0   0.0   18.5  65.2    -6.4    381  1.9
  9750    2.5  36.5   045    3    1   7.1   3.9   18.0  64.4    -6.9    364  1.8
  9500    3.1  37.6   055    5    2   8.7   4.8   17.9  64.2    -7.0    338  1.7
  9250    3.8  38.8   060    7    3   8.3   4.5   17.8  64.0    -7.1    312  1.6
  9000    4.4  39.9   060    9    5   8.4   4.6   17.7  63.9    -7.2    285  1.5
  8750    5.0  41.0   060    9    5   8.4   4.6   17.6  63.7    -7.3    259  1.3
  8500    5.6  42.1   055    9    4   8.4   4.6   17.5  63.5    -7.5    233  1.2
  8250    6.3  43.3   055    8    4   8.4   4.6   17.4  63.3    -7.6    207  1.1
  8000    6.9  44.4   050    8    4   8.2   4.5   17.3  63.1    -7.7    181  0.9
  7750    7.5  45.5   050    7    4   8.8   4.9   17.2  62.9    -7.9    155  0.8
  7500    8.1  46.6   050    6    3   6.5   3.6   17.0  62.7    -8.0    129  0.7
  7250    8.3  46.9   050    5    3  -0.2  -0.1   16.5  61.8    -8.5    115  0.6
  7000    8.2  46.8   050    4    2   1.7   0.9   15.7  60.3    -9.4    111  0.6
  6750    8.6  47.5   060    5    2   7.4   4.1   15.4  59.7    -9.8     92  0.5
  6500    9.2  48.6   070    6    3   7.7   4.2   15.2  59.4   -10.0     67  0.3
  6250    9.8  49.6   075    7    3   7.4   4.1   15.1  59.1   -10.1     43  0.2
  6000   10.3  50.5   080    8    4   8.3   4.6   14.9  58.9   -10.3     18  0.1
  5750   10.9  51.6   080    7    4   5.1   2.8   14.8  58.6   -10.5      M    M
  5500   11.0  51.8   085    6    3   0.4   0.2   14.2  57.5   -11.2      M    M
  5250   11.0  51.8   095    5    3   2.1   1.2   13.5  56.3   -11.9      M    M
  5000   11.0  51.8   100    4    2  -3.6  -2.0   12.8  55.1   -12.7      M    M

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

           05/29/2015 at 0900 MDT          |       05/29/2015 at 1200 MDT
                                           |
K index... +16.6  LI... +273.6             | K index... +17.7  LI... +272.5
CAPE... +6.8  CIN... -18.5                 | CAPE... +115.9  CIN... -28.1
                                           |
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  290  15  8   2.0   1.1 | -58.7 -73.7  285  15  8   2.5   1.3
 45000 -55.5 -67.9  300  28 15   0.1   0.0 | -55.4 -67.7  300  22 11   0.3   0.2
 40000 -55.5 -67.9  295  48 24   0.1   0.0 | -54.9 -66.8  305  43 22   0.0   0.0
 38000 -53.8 -64.8  295  54 28   3.5   1.9 | -53.3 -63.9  305  48 25   3.1   1.7
 36000 -51.7 -61.1  295  58 30   3.5   1.9 | -51.5 -60.7  305  52 27   3.1   1.7
 34000 -49.0 -56.2  300  56 29   5.5   3.0 | -48.9 -56.0  305  50 26   5.6   3.0
 32000 -45.7 -50.3  300  46 23   5.5   3.0 | -45.6 -50.1  305  42 22   5.6   3.0
 30000 -41.8 -43.2  305  37 19   7.8   4.3 | -41.7 -43.1  305  35 18   7.5   4.1
 29000 -39.5 -39.1  305  34 17   7.8   4.3 | -39.5 -39.1  305  32 17   7.5   4.1
 28000 -37.2 -35.0  310  31 16   7.8   4.3 | -37.2 -35.0  305  29 15   7.6   4.2
 27000 -34.8 -30.6  310  28 15   8.4   4.6 | -34.8 -30.6  305  27 14   8.6   4.7
 26000 -32.3 -26.1  310  27 14   8.4   4.6 | -32.2 -26.0  305  25 13   8.6   4.7
 25000 -29.8 -21.6  310  26 14   8.4   4.6 | -29.7 -21.5  305  24 12   8.6   4.7
 24000 -27.2 -17.0  310  25 13   8.4   4.6 | -27.1 -16.8  305  23 12   8.2   4.5
 23000 -24.7 -12.5  310  25 13   8.4   4.6 | -24.7 -12.5  305  22 11   8.2   4.5
 22000 -22.2  -8.0  310  25 13   8.3   4.6 | -21.6  -6.9  310  21 11   8.3   4.6
 21000 -19.2  -2.6  310  24 12   7.7   4.2 | -19.3  -2.7  310  21 11   7.5   4.1
 20000 -17.0   1.4  310  24 12   7.7   4.2 | -17.0   1.4  310  20 10   7.5   4.1
 19500 -15.8   3.6  310  23 12   7.7   4.2 | -15.9   3.4  310  19 10   7.5   4.1
 19000 -14.7   5.5  310  23 12   7.5   4.1 | -14.8   5.4  315  19 10   7.6   4.2
 18500 -13.6   7.5  310  22 12   7.3   4.0 | -13.6   7.5  315  18  9   7.6   4.2
 18000 -12.5   9.5  310  22 11   7.4   4.0 | -12.5   9.5  315  18  9   7.6   4.2
 17500 -11.4  11.5  315  21 11   7.2   4.0 | -11.5  11.3  315  17  9   6.7   3.7
 17000 -10.4  13.3  315  20 10   7.3   4.0 | -10.5  13.1  320  16  8   6.8   3.7
 16500  -9.3  15.3  315  19 10   6.5   3.6 |  -9.5  14.9  320  15  8   6.8   3.7
 16000  -8.4  16.9  320  17  9   6.2   3.4 |  -8.5  16.7  320  14  7   6.8   3.8
 15500  -7.5  18.5  320  15  8   6.0   3.3 |  -7.5  18.5  320  13  7   6.8   3.7
 15000  -6.7  19.9  320  13  7   5.5   3.0 |  -6.5  20.3  320  11  6   6.7   3.7
 14500  -5.9  21.4  320  11  6   5.6   3.1 |  -5.6  21.9  320  10  5   6.7   3.7
 14000  -5.0  23.0  320  10  5   6.5   3.6 |  -4.6  23.7  320   8  4   6.7   3.7
 13500  -4.0  24.8  315   9  5   6.4   3.5 |  -3.6  25.5  315   7  4   6.7   3.7
 13000  -3.1  26.4  315   8  4   7.0   3.8 |  -2.5  27.5  315   6  3   7.2   4.0
 12500  -2.1  28.2  310   7  4   6.9   3.8 |  -1.5  29.3  310   5  3   7.1   3.9
 12000  -1.1  30.0  310   6  3   7.7   4.2 |  -0.3  31.5  305   5  3   8.8   4.9
 11500   0.0  32.0  320   5  3   7.9   4.3 |   1.0  33.8  305   5  3   8.8   4.8
 11000   1.0  33.8  335   4  2   6.1   3.3 |   2.1  35.8  305   5  3   7.1   3.9
 10500   1.8  35.2  355   3  1   6.8   3.7 |   3.2  37.8  320   4  2   7.5   4.1
 10250   2.2  36.0  005   3  1   4.1   2.2 |   3.6  38.5  330   3  2   2.9   1.6
 10000   2.5  36.5  010   2  1   6.9   3.8 |   3.7  38.7  335   3  2   5.0   2.7
  9750   3.3  37.9  020   2  1  11.8   6.5 |   4.4  39.9  345   3  1  10.1   5.5
  9500   4.0  39.2  025   3  1  10.6   5.8 |   5.0  41.0  360   3  1   8.5   4.7
  9250   4.7  40.5  035   3  1   7.4   4.1 |   5.6  42.1  005   3  1   6.4   3.5
  9000   5.2  41.4  040   3  2   6.2   3.4 |   6.0  42.8  010   3  1   7.0   3.9
  8750   5.7  42.3  040   4  2   8.8   4.8 |   6.6  43.9  015   3  1   9.9   5.4
  8500   6.4  43.5  045   4  2   8.3   4.5 |   7.3  45.1  015   3  1   9.4   5.1
  8250   6.9  44.4  045   5  3   7.1   3.9 |   7.9  46.2  015   3  1   8.8   4.8
  8000   7.5  45.5  045   6  3   6.8   3.7 |   8.6  47.5  015   3  1   8.9   4.9
  7750   8.0  46.4  050   6  3   7.6   4.2 |   9.2  48.6  015   3  1   9.5   5.2
  7500   8.6  47.5  050   7  4   6.8   3.7 |   9.9  49.8  015   3  1  10.1   5.6
  7250   9.0  48.2  050   7  4   5.7   3.1 |  10.7  51.3  015   2  1  10.3   5.7
  7000   9.5  49.1  055   7  4   5.9   3.2 |  11.4  52.5  015   2  1  10.3   5.6
  6750   9.9  49.8  055   7  3   6.1   3.4 |  12.2  54.0  010   2  1  10.0   5.5
  6500  10.4  50.7  055   6  3   6.6   3.6 |  13.0  55.4  010   2  1  10.2   5.6
  6250  10.9  51.6  055   5  3   7.7   4.2 |  13.7  56.7  010   2  1  10.4   5.7
  6000  11.3  52.3  060   5  2   4.7   2.6 |  14.5  58.1  005   2  1  10.4   5.7
  5750  11.7  53.1  060   4  2  10.2   5.6 |  15.5  59.9  005   2  1  17.5   9.6
  5500  13.0  55.4  060   4  2  27.5  15.1 |  17.2  63.0  360   2  1  28.7  15.8
  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

           05/29/2015 at 1500 MDT          |       05/29/2015 at 1800 MDT
                                           |
K index... +16.3  LI... +272.5             | K index... +15.7  LI... +272.7
CAPE... +145.0  CIN... -41.3               | CAPE... +157.9  CIN... -48.3
                                           |
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 -58.9 -74.0  285  18  9   2.0   1.1 | -59.3 -74.7  295  18  9   1.5   0.8
 45000 -56.2 -69.2  295  20 10   0.4   0.2 | -57.3 -71.1  290  22 11   0.4   0.2
 40000 -55.8 -68.4  310  39 20  -0.0  -0.0 | -56.8 -70.2  325  37 19  -0.2  -0.1
 38000 -53.9 -65.0  315  44 22   3.7   2.0 | -54.5 -66.1  330  42 22   4.4   2.4
 36000 -51.7 -61.1  315  47 24   3.7   2.0 | -51.9 -61.4  330  47 24   4.4   2.4
 34000 -48.9 -56.0  315  47 24   5.9   3.2 | -48.8 -55.8  330  44 23   5.7   3.2
 32000 -45.3 -49.5  315  42 21   5.9   3.2 | -45.4 -49.7  335  33 17   5.7   3.2
 30000 -41.4 -42.5  315  37 19   7.4   4.1 | -41.2 -42.2  340  25 13   8.6   4.7
 29000 -39.2 -38.6  315  34 18   7.4   4.1 | -38.6 -37.5  340  23 12   8.6   4.7
 28000 -36.4 -33.5  315  31 16   7.4   4.1 | -35.4 -31.7  340  20 10   8.6   4.7
 27000 -34.0 -29.2  315  29 15   8.5   4.7 | -32.9 -27.2  340  18  9   8.3   4.6
 26000 -31.4 -24.5  315  28 14   8.5   4.7 | -30.4 -22.7  335  17  9   8.3   4.6
 25000 -28.9 -20.0  315  26 13   8.5   4.7 | -27.9 -18.2  335  16  8   8.3   4.6
 24000 -26.4 -15.5  315  25 13   8.4   4.6 | -25.4 -13.7  330  15  8   8.1   4.5
 23000 -23.9 -11.0  310  24 12   8.4   4.6 | -23.0  -9.4  330  16  8   8.1   4.5
 22000 -21.4  -6.5  310  23 12   8.4   4.6 | -20.6  -5.1  325  16  8   8.1   4.5
 21000 -19.0  -2.2  310  22 11   7.7   4.2 | -18.2  -0.8  325  16  8   7.7   4.2
 20000 -16.7   1.9  310  20 11   7.7   4.2 | -15.9   3.4  325  16  8   7.7   4.2
 19500 -15.5   4.1  310  20 10   7.7   4.2 | -14.8   5.4  325  16  8   7.7   4.2
 19000 -14.4   6.1  310  19 10   7.7   4.2 | -13.6   7.5  325  17  9   7.3   4.0
 18500 -13.3   8.1  310  19 10   7.5   4.1 | -12.6   9.3  325  16  8   6.8   3.7
 18000 -12.2  10.0  310  18  9   7.6   4.2 | -11.6  11.1  325  16  8   6.8   3.7
 17500 -11.1  12.0  310  17  9   6.6   3.6 | -10.6  12.9  325  16  8   7.3   4.0
 17000 -10.1  13.8  310  16  8   6.7   3.7 |  -9.5  14.9  330  16  8   7.3   4.0
 16500  -9.1  15.6  310  15  8   6.8   3.8 |  -8.4  16.9  330  15  8   7.3   4.0
 16000  -8.1  17.4  310  14  7   6.9   3.8 |  -7.4  18.7  330  15  8   7.4   4.1
 15500  -7.1  19.2  315  13  7   7.0   3.9 |  -6.3  20.7  330  14  7   7.5   4.1
 15000  -6.0  21.2  315  12  6   7.5   4.1 |  -5.2  22.6  330  13  7   7.7   4.2
 14500  -5.0  23.0  310  11  6   7.4   4.1 |  -4.0  24.8  330  13  7   7.7   4.2
 14000  -3.9  25.0  310  10  5   7.8   4.3 |  -2.9  26.8  330  12  6   7.8   4.3
 13500  -2.2  28.0  305   8  4   7.7   4.2 |  -1.2  29.8  340  10  5   7.8   4.3
 13000  -1.1  30.0  310   7  4   7.7   4.2 |  -0.1  31.8  340   9  4   7.8   4.3
 12500   0.0  32.0  310   6  3   7.7   4.2 |   1.0  33.8  350   8  4   8.0   4.4
 12000   1.2  34.2  315   6  3   7.8   4.3 |   2.2  36.0  355   7  3   8.3   4.6
 11500   2.3  36.1  320   5  3   7.9   4.3 |   3.4  38.1  360   6  3   8.4   4.6
 11000   3.5  38.3  325   4  2   7.9   4.4 |   4.6  40.3  005   6  3   8.4   4.6
 10500   4.7  40.5  335   4  2   5.0   2.8 |   5.9  42.6  010   5  3   4.3   2.4
 10250   5.0  41.0  335   4  2   5.8   3.2 |   6.1  43.0  010   5  3   5.1   2.8
 10000   5.6  42.1  340   4  2  10.5   5.8 |   6.8  44.2  015   5  3  11.2   6.1
  9750   6.4  43.5  340   4  2  10.3   5.7 |   7.5  45.5  015   5  3   9.9   5.4
  9500   7.1  44.8  345   4  2   8.4   4.6 |   8.2  46.8  015   5  2   9.1   5.0
  9250   7.6  45.7  345   4  2   6.0   3.3 |   8.8  47.8  015   5  2   7.5   4.1
  9000   8.1  46.6  345   4  2   8.4   4.6 |   9.4  48.9  015   4  2   8.4   4.6
  8750   8.7  47.7  345   4  2   9.6   5.3 |  10.1  50.2  015   4  2   8.9   4.9
  8500   9.4  48.9  345   4  2   9.5   5.2 |  10.7  51.3  015   4  2   8.6   4.7
  8250  10.1  50.2  345   4  2   9.8   5.4 |  11.3  52.3  010   3  2   8.4   4.6
  8000  10.7  51.3  340   3  2   9.7   5.3 |  11.9  53.4  010   3  2   8.7   4.8
  7750  11.5  52.7  340   3  2   9.7   5.3 |  12.5  54.5  005   3  1   9.0   4.9
  7500  12.2  54.0  340   3  2  10.1   5.5 |  13.2  55.8  005   3  1   9.5   5.2
  7250  13.0  55.4  335   3  2  10.3   5.7 |  13.9  57.0  360   2  1   9.8   5.4
  7000  13.7  56.7  335   3  2  10.1   5.5 |  14.6  58.3  360   2  1   9.8   5.4
  6750  14.5  58.1  335   3  2  10.6   5.8 |  15.3  59.5  355   2  1  10.2   5.6
  6500  15.3  59.5  330   3  1  11.1   6.1 |  16.1  61.0  355   2  1  10.4   5.7
  6250  16.1  61.0  330   3  1  11.3   6.2 |  16.9  62.4  350   2  1  10.6   5.8
  6000  17.0  62.6  325   3  1  10.5   5.8 |  17.7  63.9  345   2  1   9.9   5.4
  5750  17.7  63.9  325   3  1  12.7   6.9 |  18.4  65.1  340   1  1   9.9   5.4
  5500  18.8  65.8  325   3  1  15.6   8.6 |  19.1  66.4  340   2  1  10.9   6.0
  5250  19.9  67.8  325   3  2  13.3   7.3 |  19.9  67.8  345   2  1  10.1   5.5
  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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