Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 091239
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0539 MST Tuesday, February 9, 2016

This forecast is for Tuesday, February 9, 2016:

If the trigger temperature of 53.8 F/12.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 162 ft/min (0.8 m/s)
   Maximum height of thermals.................. 6509 ft MSL (1670 ft AGL)

Forecast maximum temperature................... 43.0 F/6.6 C
Time of trigger temperature.................... None
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................. 5572 ft MSL (732 ft AGL)
Thermal soaring outlook for Wednesday 02/10.... Poor

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

Remarks...

Sunrise/Sunset.................... 07:12:58 / 17:42:46 MST
Total possible sunshine........... 10 hr 29 min 48 sec (629 min 48 sec)
Altitude of sun at 12:28:12 MST... 36.26 degrees

Upper air data from rawinsonde observation taken on 02/09/2016 at 0500 MST

Freezing level.................. 5487 ft MSL (648 ft AGL)
Additional freezing levels...... 8828 ft MSL (3989 ft AGL)
                                 9146 ft MSL (4307 ft AGL)
Convective condensation level... 18669 ft MSL (13830 ft AGL)
Lifted condensation level....... 10540 ft MSL (5701 ft AGL)
Lifted index.................... +16.0
K index......................... -27.6

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -60.7 -77.3   330   56   29  -0.8  -0.4  100.4 212.6    53.6      M    M
 45000  -56.4 -69.5   350   68   35  -1.8  -1.0   81.5 178.7    46.1      M    M
 40000  -63.7 -82.7   350   46   24  -6.8  -3.7   47.0 116.5    26.7      M    M
 38000  -60.8 -77.4   345   48   25   7.5   4.1   42.4 108.3    24.4      M    M
 36000  -55.9 -68.6   340   51   26   8.7   4.7   41.0 105.8    24.1      M    M
 34000  -50.7 -59.3   340   54   28   8.7   4.8   40.0 104.1    24.1      M    M
 32000  -45.7 -50.3   335   55   28   7.7   4.3   39.0 102.2    24.0      M    M
 30000  -41.0 -41.8   340   44   23   8.9   4.9   36.5  97.7    22.8      M    M
 29000  -38.4 -37.1   340   43   22   8.9   4.9   36.0  96.9    22.7      M    M
 28000  -35.7 -32.3   340   42   22   8.9   4.9   35.7  96.3    22.7      M    M
 27000  -33.1 -27.6   345   42   21   7.4   4.1   35.5  95.9    22.8      M    M
 26000  -31.0 -23.8   345   41   21   8.5   4.7   34.4  94.0    22.3      M    M
 25000  -28.6 -19.5   345   40   21   6.8   3.7   33.8  92.9    22.1      M    M
 24000  -26.5 -15.7   345   38   20   7.5   4.1   32.7  90.9    21.4      M    M
 23000  -24.3 -11.7   340   39   20   7.4   4.0   31.9  89.3    21.0      M    M
 22000  -21.8  -7.2   340   39   20   8.7   4.8   31.3  88.3    20.7      M    M
 21000  -19.4  -2.9   335   40   21   6.2   3.4   30.7  87.3    20.5      M    M
 20000  -17.5   0.5   350   41   21   6.5   3.6   29.6  85.2    19.7      M    M
 19500  -16.5   2.3   350   40   21   6.4   3.5   29.0  84.1    19.3      M    M
 19000  -15.6   3.9   355   39   20   5.7   3.1   28.4  83.1    18.9      M    M
 18500  -14.5   5.9   355   40   21   8.2   4.5   27.8  82.1    18.6      M    M
 18000  -13.3   8.1   355   39   20   9.0   4.9   27.6  81.6    18.5      M    M
 17500  -11.9  10.6   355   38   20   9.4   5.1   27.5  81.5    18.5      M    M
 17000   -9.8  14.4   355   37   19   9.2   5.0   27.4  81.3    18.6      M    M
 16500   -8.6  16.5   355   36   18   6.8   3.7   27.1  80.7    18.4      M    M
 16000   -7.5  18.5   355   35   18   7.0   3.8   26.6  79.9    18.1      M    M
 15500   -6.5  20.3   355   36   19   7.0   3.8   26.1  79.1    17.8      M    M
 15000   -5.4  22.3   355   37   19   6.8   3.7   25.7  78.2    17.5      M    M
 14500   -4.6  23.7   360   34   18   4.3   2.4   24.9  76.9    16.9      M    M
 14000   -4.0  24.8   360   32   16   4.5   2.4   24.1  75.3    16.3      M    M
 13500   -3.2  26.2   360   30   16   5.2   2.8   23.2  73.8    15.6      M    M
 13000   -2.5  27.5   355   29   15   5.3   2.9   22.5  72.5    15.0      M    M
 12500   -1.7  28.9   355   27   14   5.3   2.9   21.8  71.2    14.4      M    M
 12000   -0.9  30.4   350   26   13   5.8   3.2   21.1  69.9    13.8      M    M
 11500   -0.4  31.3   360   25   13   1.1   0.6   20.1  68.2    12.9      M    M
 11000   -0.9  30.4   005   25   13  -3.8  -2.1   18.0  64.4    11.0      M    M
 10500   -0.4  31.3   015   26   13   2.8   1.6   17.0  62.6    10.1      M    M
 10250   -0.6  30.9   015   24   12  -4.5  -2.5   16.1  61.0     9.2      M    M
 10000   -0.9  30.4   015   21   11   0.9   0.5   15.1  59.2     8.2      M    M
  9750   -0.5  31.1   015   18    9   5.1   2.8   14.7  58.4     7.9      M    M
  9500   -0.2  31.6   015   16    8   5.5   3.0   14.2  57.6     7.5      M    M
  9250    0.1  32.2   015   13    7  -0.1  -0.0   13.8  56.9     7.1      M    M
  9000   -0.2  31.6   015   10    5  -1.4  -0.8   12.8  55.1     6.1      M    M
  8750    0.1  32.2   025    9    5   6.4   3.5   12.3  54.2     5.6      M    M
  8500    0.6  33.1   035    9    5   7.1   3.9   12.1  53.8     5.4      M    M
  8250    1.1  34.0   050    9    5   6.8   3.7   11.9  53.4     5.2      M    M
  8000    1.6  34.9   060   10    5   7.3   4.0   11.7  53.0     5.0      M    M
  7750    2.0  35.6   065    9    5   0.5   0.2   11.3  52.4     4.6      M    M
  7500    1.7  35.1   070    8    4  -5.1  -2.8   10.3  50.5     3.6      M    M
  7250    1.4  34.5   075    7    4  -3.4  -1.9    9.2  48.6     2.6      M    M
  7000    1.1  34.0   085    6    3  -4.6  -2.5    8.2  46.7     1.6      M    M
  6750    0.8  33.4   085    7    3  -0.0  -0.0    7.2  44.9     0.6      M    M
  6500    1.0  33.8   085    7    4   4.2   2.3    6.7  44.0     0.1      M    M
  6250    1.3  34.3   085    8    4   2.8   1.5    6.2  43.1    -0.4    151  0.8
  6000    1.5  34.7   085    9    5   4.2   2.3    5.7  42.2    -0.9    136  0.7
  5750    1.7  35.1   100    9    5   0.1   0.0    5.2  41.3    -1.4    122  0.6
  5500    0.9  33.6   115   10    5 -26.3 -14.4    3.7  38.6    -2.9    139  0.7
  5250   -1.6  29.1   125   12    6 -30.4 -16.7    0.3  32.6    -6.2    209  1.1
  5000   -2.7  27.1   125    7    4  -0.8  -0.4   -1.6  29.2    -8.1    235  1.2

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

           02/09/2016 at 0800 MST          |       02/09/2016 at 1100 MST
                                           |
K index... +2.7  LI... +278.5              | K index... +3.4  LI... +278.4
CAPE... 0.0  CIN... -0.0                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -61.2 -78.2  350  53 27   2.2   1.2 | -61.7 -79.1  340  56 29   3.2   1.7
 45000 -58.4 -73.1  350  63 32  -1.9  -1.0 | -57.6 -71.7  340  59 31  -1.3  -0.7
 40000 -61.1 -78.0  340  45 23  -1.6  -0.9 | -59.6 -75.3  340  45 23  -1.4  -0.8
 38000 -58.3 -72.9  340  45 23   6.2   3.4 | -57.5 -71.5  340  42 22   4.8   2.6
 36000 -54.6 -66.3  340  46 24   6.2   3.4 | -54.6 -66.3  340  39 20   4.8   2.7
 34000 -50.4 -58.7  345  46 24   7.8   4.3 | -50.9 -59.6  340  37 19   8.2   4.5
 32000 -45.7 -50.3  345  44 23   7.8   4.3 | -45.4 -49.7  345  37 19   8.1   4.5
 30000 -41.1 -42.0  345  41 21   7.7   4.2 | -40.6 -41.1  345  36 19   8.0   4.4
 29000 -38.7 -37.7  345  40 20   7.7   4.2 | -38.2 -36.8  345  35 18   8.0   4.4
 28000 -36.4 -33.5  345  38 20   7.7   4.2 | -35.8 -32.4  345  35 18   8.0   4.4
 27000 -34.1 -29.4  345  37 19   7.8   4.3 | -33.5 -28.3  345  34 18   7.3   4.0
 26000 -31.8 -25.2  345  36 19   7.8   4.3 | -31.3 -24.3  345  34 17   7.3   4.0
 25000 -29.4 -20.9  345  35 18   7.8   4.3 | -29.1 -20.4  340  33 17   7.3   4.0
 24000 -27.1 -16.8  345  34 18   7.5   4.1 | -26.9 -16.4  340  32 17   7.2   3.9
 23000 -24.9 -12.8  345  34 17   7.5   4.1 | -24.8 -12.6  345  32 16   7.2   3.9
 22000 -22.6  -8.7  350  33 17   7.6   4.1 | -22.6  -8.7  345  31 16   7.2   3.9
 21000 -19.8  -3.6  350  33 17   7.6   4.2 | -20.5  -4.9  345  30 15   7.5   4.1
 20000 -17.5   0.5  355  33 17   7.6   4.2 | -18.2  -0.8  350  29 15   7.5   4.1
 19500 -16.3   2.7  355  33 17   7.6   4.2 | -17.1   1.2  350  29 15   7.5   4.1
 19000 -15.2   4.6  360  33 17   8.8   4.8 | -16.0   3.2  355  29 15   7.8   4.3
 18500 -13.8   7.2  360  33 17   9.0   4.9 | -14.1   6.6  355  28 15   8.4   4.6
 18000 -12.4   9.7  360  33 17   8.5   4.7 | -12.9   8.8  355  28 14   8.2   4.5
 17500 -11.3  11.7  360  33 17   6.7   3.7 | -11.7  10.9  360  28 14   7.9   4.3
 17000 -10.3  13.5  005  32 17   6.7   3.7 | -10.5  13.1  360  27 14   7.9   4.4
 16500  -9.3  15.3  005  32 16   7.4   4.1 |  -9.4  15.1  360  27 14   7.4   4.1
 16000  -8.2  17.2  005  31 16   7.4   4.1 |  -8.3  17.1  360  26 14   7.5   4.1
 15500  -7.1  19.2  005  31 16   7.3   4.0 |  -7.2  19.0  360  26 13   7.1   3.9
 15000  -6.0  21.2  005  30 15   7.2   3.9 |  -6.1  21.0  005  25 13   7.0   3.8
 14500  -4.9  23.2  010  29 15   7.2   4.0 |  -5.1  22.8  005  24 12   7.6   4.2
 14000  -3.8  25.2  005  27 14   7.4   4.0 |  -3.9  25.0  005  24 12   8.2   4.5
 13500  -2.7  27.1  005  25 13   7.2   3.9 |  -2.7  27.1  360  24 12   7.6   4.2
 13000  -1.7  28.9  005  25 13   6.1   3.4 |  -1.7  28.9  360  25 13   6.1   3.4
 12500  -0.8  30.6  005  26 13   5.9   3.3 |  -0.8  30.6  005  26 13   6.1   3.3
 12000  -0.2  31.6  005  27 14   3.0   1.6 |   0.1  32.2  005  26 13   5.9   3.2
 11500   0.2  32.4  005  28 14   3.1   1.7 |   1.0  33.8  005  27 14   4.9   2.7
 11000   0.4  32.7  005  28 14   0.6   0.3 |   1.2  34.2  005  25 13   0.3   0.2
 10500   0.4  32.7  005  27 14   0.5   0.3 |   1.3  34.3  005  24 12  -0.1  -0.1
 10250   0.4  32.7  005  26 13  -1.5  -0.8 |   1.1  34.0  010  22 11  -2.4  -1.3
 10000   0.2  32.4  010  24 12  -1.9  -1.1 |   0.8  33.4  010  21 11  -2.7  -1.5
  9750   0.1  32.2  010  22 11  -0.4  -0.2 |   0.6  33.1  010  19 10  -2.2  -1.2
  9500   0.0  32.0  010  20 10  -1.1  -0.6 |   0.4  32.7  015  17  9  -2.3  -1.3
  9250  -0.1  31.8  010  17  9  -2.7  -1.5 |   0.2  32.4  015  15  8  -2.6  -1.4
  9000  -0.3  31.5  015  15  8  -2.8  -1.5 |   0.0  32.0  020  13  7  -2.6  -1.4
  8750  -0.5  31.1  020  12  6  -2.3  -1.3 |  -0.1  31.8  025  11  6  -1.7  -1.0
  8500  -0.5  31.1  030  10  5   0.6   0.4 |  -0.1  31.8  035  10  5   0.8   0.4
  8250  -0.4  31.3  040   8  4   2.5   1.4 |   0.0  32.0  040   9  4   2.1   1.2
  8000  -0.2  31.6  050   7  4   1.8   1.0 |   0.2  32.4  050   8  4   1.3   0.7
  7750  -0.0  32.0  065   7  3   2.7   1.5 |   0.3  32.5  060   7  4   3.3   1.8
  7500   0.2  32.4  075   7  3   4.3   2.4 |   0.7  33.3  070   6  3   4.9   2.7
  7250   0.6  33.1  080   6  3   4.7   2.6 |   1.0  33.8  075   5  3   4.2   2.3
  7000   0.9  33.6  090   6  3   4.8   2.6 |   1.3  34.3  080   5  2   4.1   2.2
  6750   1.2  34.2  095   6  3   2.0   1.1 |   1.5  34.7  085   4  2   1.1   0.6
  6500   1.2  34.2  105   5  3  -1.1  -0.6 |   1.5  34.7  100   4  2  -0.5  -0.3
  6250   1.2  34.2  115   5  3   0.7   0.4 |   1.5  34.7  115   4  2  -0.1  -0.0
  6000   1.2  34.2  125   5  3  -4.4  -2.4 |   1.5  34.7  135   4  2  -0.2  -0.1
  5750   0.3  32.5  125   6  3 -18.5 -10.1 |   1.5  34.7  135   3  2   3.4   1.8
  5500  -1.5  29.3  115   5  3 -27.3 -15.0 |   1.9  35.4  130   3  2   9.2   5.0
  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

           02/09/2016 at 1400 MST          |       02/09/2016 at 1700 MST
                                           |
K index... +2.3  LI... +277.9              | K index... +0.3  LI... +278.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
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 -61.9 -79.4  335  56 29   4.0   2.2 | -62.6 -80.7  335  57 29   4.5   2.4
 45000 -56.7 -70.1  335  59 31  -1.5  -0.8 | -56.6 -69.9  330  62 32  -0.8  -0.4
 40000 -59.1 -74.4  335  42 22  -1.5  -0.8 | -57.8 -72.0  325  45 23  -0.8  -0.4
 38000 -57.2 -71.0  335  38 20   4.4   2.4 | -56.3 -69.3  320  40 21   3.5   1.9
 36000 -54.6 -66.3  335  35 18   4.4   2.4 | -54.2 -65.6  320  37 19   3.5   1.9
 34000 -50.9 -59.6  335  33 17   8.3   4.6 | -51.0 -59.8  325  35 18   8.1   4.5
 32000 -45.4 -49.7  340  34 18   8.3   4.5 | -45.5 -49.9  325  36 18   8.1   4.4
 30000 -40.4 -40.7  340  35 18   8.3   4.5 | -40.7 -41.3  330  36 18   8.1   4.4
 29000 -37.9 -36.2  340  35 18   8.3   4.5 | -38.3 -36.9  330  35 18   8.1   4.4
 28000 -35.4 -31.7  340  35 18   8.3   4.6 | -35.9 -32.6  335  35 18   8.1   4.4
 27000 -33.2 -27.8  340  35 18   7.0   3.9 | -33.7 -28.7  335  34 18   6.8   3.7
 26000 -31.1 -24.0  340  35 18   7.0   3.8 | -31.7 -25.1  340  33 17   6.7   3.7
 25000 -29.0 -20.2  340  34 18   7.0   3.8 | -29.7 -21.5  340  32 17   6.8   3.7
 24000 -26.9 -16.4  340  34 17   7.1   3.9 | -27.6 -17.7  345  31 16   7.6   4.2
 23000 -24.8 -12.6  340  33 17   7.1   3.9 | -25.3 -13.5  345  30 15   7.6   4.2
 22000 -22.7  -8.9  340  32 16   7.1   3.9 | -23.0  -9.4  345  28 14   7.6   4.2
 21000 -20.5  -4.9  345  30 16   7.2   4.0 | -20.8  -5.4  350  27 14   7.4   4.1
 20000 -18.4  -1.1  345  29 15   7.3   4.0 | -18.6  -1.5  350  26 13   7.4   4.1
 19500 -17.3   0.9  345  28 14   7.3   4.0 | -17.5   0.5  350  25 13   7.4   4.1
 19000 -16.2   2.8  345  27 14   7.7   4.2 | -16.4   2.5  350  24 13   7.7   4.2
 18500 -14.3   6.3  345  26 14   8.5   4.7 | -15.1   4.8  350  24 12   8.5   4.7
 18000 -13.0   8.6  345  26 13   8.5   4.6 | -13.2   8.2  350  24 12   8.3   4.6
 17500 -11.8  10.8  345  24 12   8.3   4.6 | -12.0  10.4  350  23 12   8.0   4.4
 17000 -10.6  12.9  345  23 12   8.4   4.6 | -10.8  12.6  350  23 12   8.0   4.4
 16500  -9.4  15.1  345  21 11   8.1   4.5 |  -9.6  14.7  350  22 11   8.0   4.4
 16000  -8.2  17.2  345  21 11   8.2   4.5 |  -8.5  16.7  350  22 12   8.0   4.4
 15500  -7.0  19.4  350  20 10   7.1   3.9 |  -7.3  18.9  350  22 12   8.1   4.5
 15000  -6.0  21.2  350  20 10   6.7   3.7 |  -6.1  21.0  355  22 11   8.1   4.4
 14500  -5.0  23.0  355  19 10   6.4   3.5 |  -4.9  23.2  355  22 11   7.3   4.0
 14000  -4.1  24.6  355  20 10   6.0   3.3 |  -4.0  24.8  360  21 11   6.3   3.4
 13500  -3.2  26.2  360  20 10   6.1   3.3 |  -3.0  26.6  360  21 11   6.0   3.3
 13000  -2.3  27.9  360  19 10   6.2   3.4 |  -2.2  28.0  360  19 10   5.2   2.9
 12500  -1.4  29.5  360  18  9   6.3   3.4 |  -1.4  29.5  360  17  9   5.2   2.9
 12000  -0.4  31.3  005  18  9   6.4   3.5 |  -0.7  30.7  005  14  7   5.2   2.8
 11500   0.5  32.9  010  17  9   5.8   3.2 |   0.1  32.2  010  12  6   5.1   2.8
 11000   1.0  33.8  010  17  9   2.4   1.3 |   0.7  33.3  015  11  5   4.2   2.3
 10500   1.4  34.5  015  16  8   1.9   1.0 |   1.3  34.3  025   9  5   4.0   2.2
 10250   1.4  34.5  015  16  8  -0.6  -0.3 |   1.5  34.7  025   9  5   2.5   1.4
 10000   1.3  34.3  015  15  8  -0.9  -0.5 |   1.7  35.1  030   9  5   2.7   1.5
  9750   1.2  34.2  015  15  8  -0.0  -0.0 |   1.9  35.4  030   9  4   4.1   2.3
  9500   1.2  34.2  020  14  7  -0.3  -0.2 |   2.2  36.0  030   9  4   2.9   1.6
  9250   1.1  34.0  020  13  6  -0.8  -0.4 |   2.3  36.1  030   8  4   1.2   0.6
  9000   1.0  33.8  025  11  6  -0.7  -0.4 |   2.3  36.1  030   8  4   1.1   0.6
  8750   1.0  33.8  030  10  5  -0.1  -0.0 |   2.4  36.3  030   8  4   1.4   0.8
  8500   1.0  33.8  035   9  5   1.0   0.5 |   2.5  36.5  030   8  4   0.8   0.4
  8250   1.1  34.0  040   9  4   1.5   0.8 |   2.5  36.5  035   7  4   0.2   0.1
  8000   1.2  34.2  045   8  4   1.0   0.6 |   2.5  36.5  040   7  4   0.2   0.1
  7750   1.3  34.3  050   7  4   2.6   1.4 |   2.5  36.5  045   7  3   1.0   0.6
  7500   1.6  34.9  055   6  3   4.0   2.2 |   2.6  36.7  050   6  3   1.8   1.0
  7250   1.9  35.4  060   6  3   3.7   2.0 |   2.8  37.0  055   6  3   1.4   0.8
  7000   2.2  36.0  065   5  2   3.6   2.0 |   2.9  37.2  065   5  3   1.7   0.9
  6750   2.4  36.3  070   4  2   2.4   1.3 |   3.0  37.4  075   5  2   1.9   1.0
  6500   2.6  36.7  080   3  1   2.0   1.1 |   3.1  37.6  090   4  2   2.0   1.1
  6250   2.7  36.9  100   2  1   1.5   0.9 |   3.2  37.8  110   3  1   1.1   0.6
  6000   2.8  37.0  135   2  1   4.4   2.4 |   3.3  37.9  135   3  1   4.0   2.2
  5750   3.3  37.9  150   1  1  10.5   5.8 |   3.7  38.7  145   3  1   5.0   2.7
  5500   4.1  39.4  150   1  1  12.1   6.6 |   3.7  38.7  155   2  1  -1.7  -0.9
  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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