Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 251238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0638 MDT Sunday, September 25, 2016

This forecast is for Sunday, September 25, 2016:

If the trigger temperature of 58.1 F/14.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 607 ft/min (3.1 m/s)
   Maximum height of thermals.................. 13514 ft MSL (8675 ft AGL)

Forecast maximum temperature................... 72.0 F/22.7 C
Time of trigger temperature.................... 1045 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................. 13096 ft MSL (8256 ft AGL)
Thermal soaring outlook for Monday 09/26....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:05:05 / 19:06:58 MDT
Total possible sunshine........... 12 hr 1 min 53 sec (721 min 53 sec)
Altitude of sun at 13:05:32 MDT... 49.64 degrees

Upper air data from rawinsonde observation taken on 09/25/2016 at 0600 MDT

Freezing level.................. 10409 ft MSL (5570 ft AGL)
Convective condensation level... 11976 ft MSL (7137 ft AGL)
Lifted condensation level....... 13974 ft MSL (9135 ft AGL)
Lifted index.................... +5.8
K index......................... -23.9

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  -61.6 -78.9   340   30   15 -11.0  -6.0   94.3 201.7    41.5      M    M
 45000  -57.7 -71.9   355   28   14   4.9   2.7   75.0 167.0    32.7      M    M
 40000  -51.5 -60.7   015   41   21  -0.9  -0.5   62.1 143.8    26.4      M    M
 38000  -48.5 -55.3   015   58   30   6.7   3.7   57.7 135.9    24.1      M    M
 36000  -48.9 -56.0   010   74   38   1.9   1.1   48.7 119.7    18.5      M    M
 34000  -44.0 -47.2   015   77   39   8.1   4.4   47.4 117.3    18.0      M    M
 32000  -38.8 -37.8   020   85   44   7.2   3.9   45.6 114.0    17.2      M    M
 30000  -33.9 -29.0   020   81   42   9.3   5.1   44.3 111.8    16.7      M    M
 29000  -31.5 -24.7   020   81   42   7.5   4.1   43.6 110.5    16.3      M    M
 28000  -29.0 -20.2   020   82   42   8.9   4.9   43.1 109.6    16.1      M    M
 27000  -26.3 -15.3   020   82   42   8.9   4.9   42.8 109.1    16.1      M    M
 26000  -23.7 -10.7   020   73   38   6.7   3.7   42.3 108.2    15.9      M    M
 25000  -21.9  -7.4   020   65   34   6.0   3.3   40.9 105.7    14.9      M    M
 24000  -20.0  -4.0   020   57   29   6.8   3.8   39.7 103.5    14.1      M    M
 23000  -18.2  -0.8   015   50   26   5.4   3.0   38.3 100.9    13.1      M    M
 22000  -16.1   3.0   010   42   22   8.6   4.7   37.3  99.2    12.4      M    M
 21000  -13.5   7.7   010   41   21   8.7   4.8   36.9  98.4    12.2      M    M
 20000  -10.9  12.4   005   40   21   8.7   4.8   36.6  97.8    12.1      M    M
 19500   -9.6  14.7   010   39   20   8.5   4.7   36.4  97.4    12.0      M    M
 19000   -9.0  15.8   015   38   19   4.1   2.2   35.4  95.7    11.2      M    M
 18500   -7.8  18.0   015   36   19   7.5   4.1   35.0  95.0    10.9      M    M
 18000   -6.6  20.1   015   35   18   6.2   3.4   34.7  94.4    10.7      M    M
 17500   -5.9  21.4   015   33   17   3.3   1.8   33.1  91.5     9.3      M    M
 17000   -5.4  22.3   010   32   16   5.9   3.2   32.1  89.7     8.5      M    M
 16500   -4.3  24.3   010   30   16   7.1   3.9   31.6  89.0     8.1      M    M
 16000   -3.2  26.2   010   29   15   7.6   4.2   31.2  88.2     7.8      M    M
 15500   -2.3  27.9   015   31   16   3.4   1.9   30.5  87.0     7.3      M    M
 15000   -1.7  28.9   015   31   16   3.7   2.0   29.5  85.1     6.5      M    M
 14500   -1.1  30.0   015   27   14   4.4   2.4   28.5  83.3     5.6      M    M
 14000   -1.1  30.0   015   22   12 -10.4  -5.7   26.9  80.4     4.2      M    M
 13500   -4.6  23.7   015   18    9 -20.6 -11.3   21.6  70.9    -0.8    622  3.2
 13000   -6.1  21.0   015   14    7  -0.9  -0.5   18.6  65.5    -3.7    651  3.3
 12500   -5.2  22.6   020    9    5   8.7   4.8   18.0  64.4    -4.3    610  3.1
 12000   -4.0  24.8   025    5    3   8.4   4.6   17.8  64.0    -4.5    558  2.8
 11500   -2.7  27.1   015    6    3   8.4   4.6   17.5  63.6    -4.8    506  2.6
 11000   -1.5  29.3   010    6    3   8.4   4.6   17.3  63.2    -5.0    454  2.3
 10500   -0.2  31.6   005    7    4   8.5   4.6   17.1  62.8    -5.3    402  2.0
 10250    0.4  32.7   020    8    4   8.8   4.8   17.0  62.6    -5.4    375  1.9
 10000    1.1  34.0   030   10    5   8.4   4.6   16.9  62.5    -5.5    349  1.8
  9750    1.7  35.1   035   12    6  10.0   5.5   16.8  62.3    -5.6    322  1.6
  9500    2.3  36.1   045   14    7   4.1   2.2   16.8  62.2    -5.7    296  1.5
  9250    2.3  36.1   045   16    8   0.1   0.1   16.0  60.8    -6.5    290  1.5
  9000    2.5  36.5   050   19   10   4.6   2.5   15.5  59.9    -7.1    277  1.4
  8750    2.8  37.0   050   17    9   4.5   2.5   15.1  59.1    -7.5    261  1.3
  8500    3.1  37.6   050   16    8   5.6   3.1   14.7  58.4    -8.0    245  1.2
  8250    3.5  38.3   050   14    7   8.4   4.6   14.5  58.1    -8.2    222  1.1
  8000    4.2  39.6   050   12    6   9.4   5.2   14.5  58.0    -8.3    194  1.0
  7750    4.9  40.8   050   11    6   9.2   5.0   14.4  58.0    -8.3    166  0.8
  7500    5.6  42.1   050   10    5   9.3   5.1   14.4  57.9    -8.4    138  0.7
  7250    6.3  43.3   050    9    5   9.2   5.1   14.4  57.8    -8.4    110  0.6
  7000    7.0  44.6   050    8    4   9.2   5.1   14.3  57.8    -8.5     82  0.4
  6750    7.7  45.9   050    7    4   9.2   5.1   14.3  57.7    -8.6     54  0.3
  6500    8.4  47.1   045    6    3   9.2   5.1   14.2  57.6    -8.6     26  0.1
  6250    9.0  48.2   045    5    3   9.2   5.1   14.2  57.6    -8.7      M    M
  6000    9.7  49.5   040    4    2   9.2   5.0   14.2  57.5    -8.8      M    M
  5750   10.4  50.7   030    5    2   9.4   5.1   14.1  57.4    -8.8      M    M
  5500   11.1  52.0   020    5    3   8.7   4.8   14.1  57.3    -8.9      M    M
  5250   11.5  52.7   010    7    3   1.0   0.5   13.8  56.8    -9.2      M    M
  5000   10.8  51.4   355    5    2 -22.6 -12.4   12.4  54.3   -10.7      M    M

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

           09/25/2016 at 0900 MDT          |       09/25/2016 at 1200 MDT
                                           |
K index... -3.6  LI... +280.8              | K index... -4.8  LI... +279.6
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -61.4 -78.5  345  20 10   2.9   1.6 | -62.8 -81.0  340  17  9   3.2   1.7
 45000 -56.4 -69.5  355  37 19   3.9   2.2 | -57.9 -72.2  360  36 19   2.9   1.6
 40000 -50.6 -59.1  025  52 27   2.4   1.3 | -53.3 -63.9  020  59 30   4.8   2.6
 38000 -49.0 -56.2  020  63 32   2.5   1.4 | -50.5 -58.9  020  63 32   4.7   2.6
 36000 -47.5 -53.5  015  74 38   2.7   1.5 | -47.7 -53.9  015  67 34   4.8   2.6
 34000 -43.6 -46.5  020  76 39   8.3   4.5 | -43.3 -45.9  020  66 34   8.3   4.5
 32000 -38.0 -36.4  025  75 38   8.2   4.5 | -37.7 -35.9  025  65 33   8.2   4.5
 30000 -33.4 -28.1  020  71 36   7.6   4.2 | -32.5 -26.5  025  61 31   8.7   4.8
 29000 -31.1 -24.0  020  68 35   7.6   4.2 | -29.9 -21.8  025  59 30   8.7   4.8
 28000 -28.8 -19.8  020  66 34   7.7   4.2 | -27.3 -17.1  020  56 29   8.1   4.4
 27000 -26.5 -15.7  015  66 34   7.9   4.4 | -25.1 -13.2  020  54 28   7.5   4.1
 26000 -24.1 -11.4  015  66 34   8.0   4.4 | -22.8  -9.0  020  51 26   7.5   4.1
 25000 -21.7  -7.1  015  66 34   8.1   4.4 | -20.6  -5.1  020  48 25   7.6   4.2
 24000 -19.6  -3.3  015  65 33   6.8   3.7 | -18.6  -1.5  020  48 25   6.6   3.6
 23000 -17.6   0.3  020  62 32   6.8   3.7 | -16.6   2.1  020  48 25   6.7   3.7
 22000 -15.6   3.9  025  60 31   6.8   3.7 | -14.6   5.7  025  48 25   6.7   3.7
 21000 -13.6   7.5  025  52 27   6.7   3.7 | -12.8   9.0  025  44 23   6.0   3.3
 20000 -11.6  11.1  025  42 22   6.7   3.7 | -11.0  12.2  030  38 20   6.0   3.3
 19500 -10.6  12.9  025  37 19   6.7   3.7 | -10.1  13.8  035  36 18   6.0   3.3
 19000  -9.6  14.7  025  32 17   5.6   3.1 |  -8.7  16.3  035  31 16   6.2   3.4
 18500  -8.5  16.7  025  28 14   5.2   2.9 |  -7.8  18.0  035  27 14   6.2   3.4
 18000  -7.7  18.1  020  25 13   6.1   3.4 |  -6.9  19.6  035  23 12   5.6   3.1
 17500  -6.7  19.9  020  23 12   6.5   3.6 |  -6.1  21.0  030  21 11   5.6   3.1
 17000  -5.7  21.7  015  21 11   6.5   3.6 |  -5.3  22.5  025  19 10   6.2   3.4
 16500  -4.8  23.4  010  20 10   6.3   3.5 |  -4.2  24.4  020  18  9   8.1   4.4
 16000  -3.8  25.2  010  20 10   6.8   3.7 |  -3.0  26.6  015  17  9   8.6   4.7
 15500  -3.2  26.2  010  19 10   0.4   0.2 |  -2.2  28.0  015  16  8   2.4   1.3
 15000  -3.2  26.2  020  18  9   0.2   0.1 |  -1.8  28.8  015  15  8   2.9   1.6
 14500  -3.2  26.2  030  17  8   0.2   0.1 |  -1.4  29.5  020  14  7   0.8   0.4
 14000  -3.2  26.2  030  13  7   0.4   0.2 |  -1.4  29.5  025  13  6   0.2   0.1
 13500  -3.2  26.2  035  10  5   2.2   1.2 |  -1.4  29.5  030  11  6   1.4   0.8
 13000  -2.6  27.3  040   8  4   4.5   2.5 |  -1.1  30.0  030  10  5   2.6   1.4
 12500  -2.0  28.4  045   7  3   5.3   2.9 |  -0.7  30.7  035   9  4   3.8   2.1
 12000  -1.1  30.0  050   7  4   6.6   3.6 |   0.0  32.0  035   8  4   5.3   2.9
 11500  -0.1  31.8  055   8  4   6.3   3.4 |   0.8  33.4  040   7  4   5.9   3.2
 11000   0.6  33.1  055   9  4   5.6   3.1 |   1.7  35.1  040   7  4   6.5   3.6
 10500   1.4  34.5  060  10  5   5.6   3.1 |   2.7  36.9  045   8  4   5.7   3.1
 10250   1.8  35.2  060  11  6   5.6   3.1 |   3.0  37.4  045   9  4   4.2   2.3
 10000   2.2  36.0  060  12  6   5.3   2.9 |   3.4  38.1  050   9  5   7.2   4.0
  9750   2.5  36.5  055  12  6   4.8   2.6 |   4.0  39.2  050  10  5   9.6   5.3
  9500   2.9  37.2  055  13  7   5.8   3.2 |   4.6  40.3  050  11  5   6.5   3.6
  9250   3.3  37.9  050  14  7   6.5   3.6 |   4.9  40.8  050  11  6   4.3   2.4
  9000   3.7  38.7  050  15  8   6.7   3.7 |   5.3  41.5  050  12  6   5.7   3.1
  8750   4.2  39.6  050  16  8   7.3   4.0 |   5.7  42.3  050  12  6   6.7   3.7
  8500   4.7  40.5  050  15  8   7.1   3.9 |   6.1  43.0  045  12  6   6.5   3.6
  8250   5.2  41.4  050  15  8   6.5   3.6 |   6.6  43.9  045  11  6   6.1   3.4
  8000   5.7  42.3  055  15  8   7.7   4.2 |   7.0  44.6  045  11  5   6.8   3.7
  7750   6.3  43.3  055  14  7   6.9   3.8 |   7.5  45.5  040  10  5   8.7   4.8
  7500   6.7  44.1  055  14  7   3.8   2.1 |   8.2  46.8  040  10  5   9.4   5.1
  7250   6.9  44.4  055  14  7   3.0   1.6 |   8.8  47.8  040   9  5   9.1   5.0
  7000   7.2  45.0  055  13  7   3.8   2.1 |   9.5  49.1  040   9  5   8.9   4.9
  6750   7.5  45.5  055  13  7   3.9   2.2 |  10.2  50.4  040   9  4  10.0   5.5
  6500   7.7  45.9  060  11  6   3.2   1.8 |  11.0  51.8  040   8  4  11.0   6.0
  6250   8.0  46.4  060  10  5   3.9   2.1 |  11.8  53.2  040   8  4  10.9   6.0
  6000   8.2  46.8  065   8  4   2.0   1.1 |  12.6  54.7  040   7  4  10.5   5.7
  5750   8.4  47.1  065   7  4   5.9   3.2 |  13.5  56.3  040   7  4  16.5   9.1
  5500   9.2  48.6  065   6  3  17.9   9.8 |  15.2  59.4  035   7  4  27.9  15.3
  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

           09/25/2016 at 1500 MDT          |       09/25/2016 at 1800 MDT
                                           |
K index... -3.7  LI... +279.1              | K index... -7.9  LI... +279.5
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.5
                                           |
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 -63.9 -83.0  325  18  9   3.3   1.8 | -64.8 -84.6  330  21 11   2.4   1.3
 45000 -58.5 -73.3  355  26 13   3.8   2.1 | -59.9 -75.8  350  20 10   4.6   2.6
 40000 -52.8 -63.0  015  41 21   4.2   2.3 | -53.0 -63.4  015  24 12   4.6   2.5
 38000 -50.3 -58.5  015  46 24   4.2   2.3 | -50.2 -58.4  010  30 16   4.6   2.5
 36000 -47.8 -54.0  010  52 27   4.1   2.3 | -47.4 -53.3  010  37 19   4.4   2.4
 34000 -43.3 -45.9  010  52 27   8.5   4.7 | -43.0 -45.4  005  37 19   8.1   4.4
 32000 -37.6 -35.7  010  49 25   8.5   4.7 | -37.6 -35.7  005  36 18   8.2   4.5
 30000 -32.5 -26.5  015  47 24   8.4   4.6 | -32.4 -26.3  010  34 18   8.8   4.8
 29000 -30.0 -22.0  020  46 24   8.4   4.6 | -29.7 -21.5  015  34 17   8.8   4.8
 28000 -27.5 -17.5  025  46 23   8.4   4.6 | -27.1 -16.8  015  33 17   8.2   4.5
 27000 -25.0 -13.0  025  45 23   8.4   4.6 | -24.7 -12.5  015  33 17   8.1   4.4
 26000 -22.5  -8.5  025  44 23   8.4   4.6 | -22.3  -8.1  020  32 17   8.1   4.4
 25000 -19.9  -3.8  025  43 22   8.4   4.6 | -19.9  -3.8  020  32 16   8.0   4.4
 24000 -18.0  -0.4  025  42 21   6.1   3.4 | -17.7   0.1  025  31 16   7.5   4.1
 23000 -16.2   2.8  030  40 20   6.2   3.4 | -15.4   4.3  030  31 16   7.5   4.1
 22000 -14.4   6.1  030  38 19   6.2   3.4 | -13.2   8.2  035  31 16   7.2   3.9
 21000 -12.5   9.5  035  35 18   6.2   3.4 | -11.3  11.7  040  27 14   6.5   3.6
 20000 -10.6  12.9  035  31 16   6.2   3.4 |  -9.3  15.3  040  24 12   6.5   3.6
 19500  -9.7  14.5  035  30 15   6.2   3.4 |  -8.4  16.9  045  22 12   6.6   3.6
 19000  -8.3  17.1  035  27 14   6.5   3.6 |  -7.5  18.5  045  21 11   5.2   2.9
 18500  -7.3  18.9  040  25 13   6.6   3.6 |  -6.3  20.7  040  19 10   5.2   2.9
 18000  -6.3  20.7  040  22 12   6.4   3.5 |  -5.5  22.1  040  18  9   5.8   3.2
 17500  -5.3  22.5  035  20 10   6.5   3.5 |  -4.6  23.7  035  17  9   5.8   3.2
 17000  -4.3  24.3  030  17  9   6.8   3.7 |  -3.8  25.2  035  15  8   6.4   3.5
 16500  -3.3  26.1  025  16  8   7.5   4.1 |  -2.7  27.1  030  13  7   7.3   4.0
 16000  -2.2  28.0  015  15  8   7.7   4.2 |  -1.5  29.3  025  12  6   7.4   4.0
 15500  -1.2  29.8  015  15  8   5.8   3.2 |  -0.5  31.1  020  12  6   6.8   3.7
 15000  -0.3  31.5  020  16  8   6.2   3.4 |   0.5  32.9  025  14  7   7.0   3.8
 14500   0.4  32.7  025  17  9   3.3   1.8 |   1.4  34.5  025  15  8   5.0   2.7
 14000   0.8  33.4  030  16  8   2.8   1.5 |   2.1  35.8  035  16  8   4.9   2.7
 13500   1.2  34.2  035  16  8   1.8   1.0 |   2.8  37.0  040  17  9   3.5   1.9
 13000   1.3  34.3  040  15  8   1.2   0.7 |   3.1  37.6  045  17  9   2.7   1.5
 12500   1.5  34.7  045  15  8   1.9   1.0 |   3.5  38.3  055  17  9   2.3   1.3
 12000   1.8  35.2  045  13  7   2.8   1.5 |   3.7  38.7  050  16  8   2.0   1.1
 11500   2.2  36.0  045  12  6   4.5   2.4 |   3.9  39.0  045  15  8   3.7   2.0
 11000   3.1  37.6  040  11  6   6.6   3.6 |   4.7  40.5  040  15  7   5.8   3.2
 10500   4.0  39.2  040  11  5   6.2   3.4 |   5.4  41.7  035  14  7   6.2   3.4
 10250   4.5  40.1  040  10  5   6.0   3.3 |   5.9  42.6  035  14  7   7.2   4.0
 10000   5.0  41.0  035  10  5   8.4   4.6 |   6.5  43.7  035  13  7   8.6   4.7
  9750   5.6  42.1  035  10  5   9.6   5.2 |   7.1  44.8  030  13  7   9.2   5.1
  9500   6.3  43.3  030  10  5   8.2   4.5 |   7.7  45.9  030  13  7   8.7   4.8
  9250   6.8  44.2  030   9  5   7.0   3.8 |   8.4  47.1  030  13  7   8.1   4.5
  9000   7.4  45.3  025   9  4   8.8   4.8 |   9.0  48.2  025  12  6   9.2   5.1
  8750   8.0  46.4  025   8  4  10.2   5.6 |   9.7  49.5  025  12  6  10.0   5.5
  8500   8.7  47.7  025   8  4   9.0   4.9 |  10.4  50.7  025  12  6   8.5   4.7
  8250   9.3  48.7  025   8  4   8.2   4.5 |  11.0  51.8  020  11  6   7.6   4.2
  8000  10.0  50.0  025   8  4   9.5   5.2 |  11.6  52.9  020  10  5   8.5   4.7
  7750  10.7  51.3  025   7  4  10.8   5.9 |  12.2  54.0  020   9  5   9.5   5.2
  7500  11.5  52.7  025   7  4  10.2   5.6 |  12.9  55.2  020   9  4   9.3   5.1
  7250  12.2  54.0  025   7  4  10.1   5.5 |  13.6  56.5  015   8  4   9.1   5.0
  7000  13.0  55.4  025   7  3   9.4   5.2 |  14.3  57.7  015   8  4   9.3   5.1
  6750  13.7  56.7  025   7  3   9.7   5.3 |  15.0  59.0  015   7  4   9.7   5.3
  6500  14.5  58.1  025   6  3  10.7   5.9 |  15.8  60.4  015   7  3   9.9   5.4
  6250  15.2  59.4  025   6  3  10.5   5.8 |  16.5  61.7  015   6  3   9.8   5.4
  6000  16.0  60.8  025   6  3  10.5   5.8 |  17.2  63.0  015   6  3   9.8   5.4
  5750  16.9  62.4  020   6  3  16.7   9.1 |  18.0  64.4  015   6  3  11.4   6.3
  5500  18.6  65.5  020   6  3  27.0  14.8 |  18.9  66.0  015   6  3  14.4   7.9
  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
________________________________________________________________________________

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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