Soaring Guidance
Issued by NWS Grand Junction, CO

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698
UXUS97 KGJT 061226
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0626 MDT Friday, May 6, 2016

This forecast is for Friday, May 6, 2016:

If the trigger temperature of 74.6 F/23.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 910 ft/min (4.6 m/s)
   Maximum height of thermals.................. 14578 ft MSL (9739 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5281 ft MSL (442 ft AGL)
Thermal soaring outlook for Saturday 05/07..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:09:37 / 20:11:37 MDT
Total possible sunshine........... 14 hr 2 min 0 sec (842 min 0 sec)
Altitude of sun at 13:10:47 MDT... 67.69 degrees

Upper air data from rawinsonde observation taken on 05/06/2016 at 0600 MDT

Freezing level.................. 13189 ft MSL (8350 ft AGL)
Convective condensation level... 15974 ft MSL (11135 ft AGL)
Lifted condensation level....... 15300 ft MSL (10461 ft AGL)
Lifted index.................... +0.2
K index......................... +25.2

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -59.5 -75.1   225   35   18  -8.5  -4.7  100.4 212.7    43.1      M    M
 45000  -63.3 -81.9   200   40   20   0.2   0.1   69.2 156.6    27.1      M    M
 40000  -62.3 -80.1   205   54   28 -10.4  -5.7   47.6 117.6    14.9      M    M
 38000  -60.1 -76.2   180   36   19   8.5   4.6   42.0 107.7    11.5      M    M
 36000  -55.9 -68.6   155   33   17   9.5   5.2   39.6 103.2    10.1      M    M
 34000  -49.9 -57.8   160   36   19   8.3   4.6   38.7 101.7     9.8      M    M
 32000  -44.7 -48.5   170   41   21   8.9   4.9   37.8 100.1     9.4      M    M
 30000  -39.8 -39.6   170   42   22   7.7   4.2   36.8  98.2     8.9      M    M
 29000  -37.5 -35.5   165   40   21   7.7   4.2   36.0  96.7     8.3      M    M
 28000  -35.1 -31.2   170   39   20   8.7   4.8   35.2  95.3     7.8      M    M
 27000  -32.4 -26.3   175   38   20   8.9   4.9   34.7  94.5     7.6      M    M
 26000  -29.8 -21.6   180   38   20   8.9   4.9   34.4  94.0     7.4      M    M
 25000  -27.1 -16.8   185   38   20   9.6   5.3   34.3  93.7     7.4      M    M
 24000  -24.5 -12.1   190   41   21   8.3   4.5   33.9  93.0     7.1      M    M
 23000  -22.1  -7.8   190   43   22   8.1   4.5   33.3  92.0     6.7      M    M
 22000  -19.6  -3.3   190   42   21   7.2   4.0   32.8  91.1     6.3      M    M
 21000  -17.9  -0.2   185   40   21   7.7   4.2   31.5  88.7     5.2      M    M
 20000  -15.5   4.1   185   39   20   7.9   4.4   30.9  87.6     4.7      M    M
 19500  -14.3   6.3   185   37   19   8.6   4.7   30.6  87.1     4.5      M    M
 19000  -13.0   8.6   185   34   18   7.3   4.0   30.4  86.8     4.4      M    M
 18500  -11.5  11.3   185   32   17   7.0   3.8   29.6  85.3     3.7      M    M
 18000  -10.5  13.1   180   32   16   7.1   3.9   29.1  84.4     3.2      M    M
 17500   -9.5  14.9   180   31   16   7.1   3.9   28.7  83.7     2.8      M    M
 17000   -8.4  16.9   180   30   16   8.1   4.5   28.3  83.0     2.4      M    M
 16500   -7.2  19.0   175   30   15   8.2   4.5   28.1  82.6     2.2      M    M
 16000   -6.4  20.5   175   30   15   3.6   2.0   27.4  81.3     1.6      M    M
 15500   -5.8  21.6   180   34   17   5.9   3.2   26.5  79.7     0.7      M    M
 15000   -4.7  23.5   180   37   19   6.7   3.7   26.0  78.8     0.3      M    M
 14500   -3.7  25.3   175   35   18   8.8   4.8   25.6  78.1    -0.1    896  4.6
 14000   -2.2  28.0   175   34   17   9.6   5.3   25.6  78.1    -0.1    838  4.3
 13500   -0.8  30.6   175   31   16   9.6   5.3   25.6  78.0    -0.1    780  4.0
 13000    0.7  33.3   175   28   15   9.6   5.3   25.5  78.0    -0.2    722  3.7
 12500    2.1  35.8   170   26   13   9.1   5.0   25.5  78.0    -0.2    664  3.4
 12000    3.4  38.1   170   23   12   8.3   4.6   25.3  77.6    -0.4    612  3.1
 11500    4.6  40.3   165   24   12   8.3   4.5   25.1  77.1    -0.6    560  2.8
 11000    5.8  42.4   165   25   13   8.3   4.5   24.8  76.7    -0.9    508  2.6
 10500    7.1  44.8   160   26   13   8.2   4.5   24.6  76.3    -1.1    456  2.3
 10250    7.7  45.9   160   27   14   8.5   4.7   24.5  76.1    -1.2    430  2.2
 10000    8.3  46.9   160   26   14   9.5   5.2   24.4  76.0    -1.2    403  2.0
  9750    9.1  48.4   155   25   13   9.9   5.4   24.4  76.0    -1.2    373  1.9
  9500    9.8  49.6   155   24   12   9.8   5.4   24.4  76.0    -1.2    344  1.7
  9250   10.6  51.1   155   23   12   9.9   5.4   24.4  76.0    -1.2    314  1.6
  9000   11.3  52.3   150   22   11   9.1   5.0   24.4  76.0    -1.2    285  1.4
  8750   11.9  53.4   150   21   11   8.5   4.6   24.4  75.8    -1.3    259  1.3
  8500   12.6  54.7   155   19   10   8.6   4.7   24.3  75.7    -1.4    232  1.2
  8250   13.2  55.8   155   18    9   8.6   4.7   24.2  75.6    -1.5    206  1.0
  8000   13.8  56.8   160   16    8   8.6   4.7   24.1  75.4    -1.6    179  0.9
  7750   14.5  58.1   160   14    7   8.6   4.7   24.0  75.3    -1.7    153  0.8
  7500   15.1  59.2   160   12    6   8.6   4.7   23.9  75.1    -1.8    126  0.6
  7250   15.7  60.3   165   10    5   8.6   4.7   23.9  74.9    -1.9    100  0.5
  7000   16.4  61.5   165    7    4   8.6   4.7   23.8  74.8    -2.0     74  0.4
  6750   17.0  62.6   160    6    3   8.6   4.7   23.7  74.6    -2.1     47  0.2
  6500   17.6  63.7   150    6    3   8.6   4.7   23.6  74.5    -2.2     21  0.1
  6250   18.3  64.9   140    5    3   8.6   4.7   23.5  74.3    -2.3      M    M
  6000   18.9  66.0   130    5    3   8.6   4.7   23.4  74.2    -2.4      M    M
  5750   19.5  67.1   110    5    2   8.9   4.9   23.3  74.0    -2.5      M    M
  5500   20.2  68.4   090    5    2   7.8   4.3   23.2  73.8    -2.6      M    M
  5250   20.6  69.1   075    5    3   5.9   3.2   23.0  73.4    -2.9      M    M
  5000   20.8  69.4   060    6    3  -3.6  -2.0   22.5  72.4    -3.5      M    M

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

           05/06/2016 at 0900 MDT          |       05/06/2016 at 1200 MDT
                                           |
K index... +22.3  LI... +273.3             | K index... +19.4  LI... +269.7
CAPE... +14.0  CIN... -57.8                | CAPE... +413.1  CIN... -31.8
                                           |
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 -59.1 -74.4  225  28 14   0.4   0.2 | -58.6 -73.5  220  31 16   0.8   0.4
 45000 -58.7 -73.7  210  43 22  -2.8  -1.5 | -57.5 -71.5  210  43 22  -2.0  -1.1
 40000 -62.3 -80.1  185  45 23  -2.3  -1.3 | -60.2 -76.4  190  49 25  -1.8  -1.0
 38000 -60.1 -76.2  170  46 24   6.8   3.7 | -58.5 -73.3  185  50 26   5.4   2.9
 36000 -56.0 -68.8  155  49 25   6.8   3.7 | -55.3 -67.5  175  50 26   5.4   2.9
 34000 -51.5 -60.7  150  52 27   8.7   4.8 | -51.0 -59.8  170  50 26   7.9   4.4
 32000 -45.7 -50.3  155  52 27   8.7   4.8 | -46.2 -51.2  160  51 26   7.9   4.3
 30000 -40.5 -40.9  160  51 26   8.4   4.6 | -41.4 -42.5  160  52 27   8.4   4.6
 29000 -38.0 -36.4  160  50 26   8.4   4.6 | -38.8 -37.8  160  52 27   8.4   4.6
 28000 -35.5 -31.9  165  50 26   8.4   4.6 | -36.3 -33.3  165  53 27   8.4   4.6
 27000 -33.1 -27.6  165  49 25   7.8   4.3 | -33.9 -29.0  165  53 27   7.8   4.3
 26000 -30.7 -23.3  170  49 25   7.9   4.3 | -31.5 -24.7  165  53 27   7.8   4.3
 25000 -28.4 -19.1  170  49 25   7.9   4.3 | -29.2 -20.6  165  53 27   7.8   4.3
 24000 -26.1 -15.0  175  49 25   7.2   3.9 | -26.8 -16.2  170  53 27   8.8   4.8
 23000 -23.9 -11.0  180  48 25   7.3   4.0 | -24.1 -11.4  170  54 28   8.8   4.9
 22000 -21.8  -7.2  180  47 24   7.3   4.0 | -21.5  -6.7  175  55 29   8.8   4.9
 21000 -19.5  -3.1  185  46 24   8.4   4.6 | -19.2  -2.6  175  54 28   4.7   2.6
 20000 -17.0   1.4  190  44 23   8.3   4.6 | -17.7   0.1  180  49 25   5.1   2.8
 19500 -15.8   3.6  190  44 22   8.4   4.6 | -17.0   1.4  185  46 24   5.1   2.8
 19000 -14.6   5.7  195  43 22   8.4   4.6 | -16.2   2.8  185  44 22   4.8   2.6
 18500 -13.4   7.9  195  42 21   8.3   4.6 | -15.3   4.5  190  41 21   9.0   4.9
 18000 -12.1  10.2  195  40 21   8.3   4.6 | -13.9   7.0  190  38 20   8.9   4.9
 17500 -10.9  12.4  195  39 20   7.9   4.4 | -12.6   9.3  190  35 18   8.9   4.9
 17000  -9.8  14.4  195  37 19   7.6   4.2 | -11.3  11.7  185  34 17   8.9   4.9
 16500  -8.7  16.3  195  35 18   7.6   4.2 | -10.0  14.0  185  32 16   8.9   4.9
 16000  -7.5  18.5  195  32 17   8.2   4.5 |  -8.0  17.6  185  30 15   8.7   4.8
 15500  -5.7  21.7  195  29 15   8.4   4.6 |  -6.7  19.9  185  29 15   8.7   4.8
 15000  -4.3  24.3  195  26 14   9.4   5.1 |  -5.4  22.3  185  27 14   8.7   4.8
 14500  -2.9  26.8  195  24 12   9.3   5.1 |  -4.1  24.6  185  25 13   8.7   4.8
 14000  -1.5  29.3  190  22 11   9.1   5.0 |  -2.7  27.1  185  23 12   9.2   5.1
 13500  -0.2  31.6  190  20 10   9.2   5.0 |  -1.4  29.5  185  21 11   9.2   5.0
 13000   1.1  34.0  190  19 10   8.6   4.7 |  -0.0  32.0  185  19 10   9.2   5.1
 12500   2.4  36.3  190  18  9   8.7   4.8 |   1.4  34.5  180  17  9   9.2   5.1
 12000   3.7  38.7  190  18  9   8.3   4.6 |   2.7  36.9  180  15  8   9.0   4.9
 11500   4.9  40.8  190  18  9   8.3   4.6 |   4.0  39.2  185  14  7   9.0   5.0
 11000   6.1  43.0  185  19 10   7.4   4.0 |   5.2  41.4  185  14  7   7.6   4.1
 10500   7.1  44.8  185  20 10   7.2   4.0 |   6.3  43.3  185  13  7   7.4   4.1
 10250   7.7  45.9  185  21 11   9.6   5.3 |   6.9  44.4  185  13  7   9.2   5.1
 10000   8.5  47.3  185  22 11   9.1   5.0 |   7.5  45.5  185  13  7   8.7   4.8
  9750   9.0  48.2  185  23 12   7.0   3.8 |   8.1  46.6  180  13  7   7.2   3.9
  9500   9.6  49.3  185  24 12   7.7   4.2 |   8.6  47.5  180  13  7   7.6   4.2
  9250  10.1  50.2  185  25 13   7.1   3.9 |   9.1  48.4  175  13  7   7.6   4.1
  9000  10.6  51.1  180  24 12   6.5   3.6 |   9.7  49.5  175  13  7   7.8   4.3
  8750  11.1  52.0  180  24 13   6.3   3.5 |  10.2  50.4  175  13  7   8.0   4.4
  8500  11.6  52.9  175  25 13   6.6   3.6 |  10.8  51.4  170  13  6   7.6   4.2
  8250  12.0  53.6  175  25 13   5.8   3.2 |  11.3  52.3  170  12  6   9.0   4.9
  8000  12.4  54.3  170  26 13   4.4   2.4 |  12.0  53.6  170  12  6   9.8   5.4
  7750  12.7  54.9  165  25 13   4.1   2.3 |  12.7  54.9  170  12  6   9.0   5.0
  7500  13.0  55.4  160  25 13   4.2   2.3 |  13.4  56.1  170  12  6   9.3   5.1
  7250  13.3  55.9  155  25 13   3.9   2.1 |  14.1  57.4  170  12  6  10.2   5.6
  7000  13.6  56.5  155  25 13   3.9   2.1 |  14.9  58.8  170  12  6  10.6   5.8
  6750  13.9  57.0  150  23 12   4.1   2.3 |  15.7  60.3  170  12  6   9.8   5.4
  6500  14.2  57.6  150  22 11   4.5   2.5 |  16.4  61.5  170  12  6  10.4   5.7
  6250  14.5  58.1  150  19 10   5.1   2.8 |  17.2  63.0  170  11  6  11.3   6.2
  6000  14.8  58.6  145  16  8   5.3   2.9 |  18.1  64.6  175  11  6  11.2   6.1
  5750  15.1  59.2  145  12  6   5.5   3.0 |  18.9  66.0  175  11  6  10.7   5.9
  5500  15.5  59.9  140  10  5   5.4   3.0 |  19.7  67.5  175  10  5  12.6   6.9
  5250  15.8  60.4  140   9  5   5.1   2.8 |  20.8  69.4  170  10  5  16.0   8.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/06/2016 at 1500 MDT          |       05/06/2016 at 1800 MDT
                                           |
K index... +26.4  LI... +270.2             | K index... +28.4  LI... +272.2
CAPE... +593.7  CIN... -12.9               | CAPE... +204.4  CIN... -24.9
                                           |
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 -58.6 -73.5  215  31 16   0.7   0.4 | -57.6 -71.7  220  25 13   1.3   0.7
 45000 -57.5 -71.5  205  41 21   0.8   0.4 | -55.7 -68.3  205  33 17   0.5   0.3
 40000 -56.2 -69.2  200  50 26   0.8   0.5 | -54.9 -66.8  205  42 21   0.6   0.3
 38000 -54.7 -66.5  200  54 28   3.4   1.9 | -53.8 -64.8  205  49 25   2.4   1.3
 36000 -52.6 -62.7  200  59 31   3.4   1.9 | -52.4 -62.3  205  57 29   2.4   1.3
 34000 -50.1 -58.2  195  63 32   5.5   3.0 | -50.5 -58.9  205  62 32   5.1   2.8
 32000 -46.8 -52.2  195  61 31   5.6   3.0 | -47.4 -53.3  200  59 30   5.2   2.8
 30000 -43.2 -45.8  190  59 30   7.5   4.1 | -43.9 -47.0  200  53 27   8.0   4.4
 29000 -40.9 -41.6  185  57 29   7.5   4.1 | -41.5 -42.7  195  48 25   8.1   4.4
 28000 -38.6 -37.5  185  56 29   7.5   4.1 | -39.1 -38.4  195  43 22   8.1   4.4
 27000 -36.4 -33.5  180  54 28   8.3   4.5 | -36.7 -34.1  190  38 20   8.5   4.7
 26000 -33.2 -27.8  175  54 28   8.6   4.7 | -33.4 -28.1  185  40 21   8.8   4.8
 25000 -30.6 -23.1  175  54 28   8.6   4.7 | -30.8 -23.4  180  42 22   8.8   4.8
 24000 -28.1 -18.6  170  54 28   8.3   4.5 | -28.2 -18.8  175  44 23   8.4   4.6
 23000 -25.6 -14.1  175  53 27   8.3   4.5 | -25.7 -14.3  175  42 22   8.4   4.6
 22000 -23.2  -9.8  175  52 27   8.3   4.5 | -23.3  -9.9  175  40 21   8.4   4.6
 21000 -20.8  -5.4  175  50 26   7.8   4.3 | -20.8  -5.4  175  39 20   8.1   4.4
 20000 -18.5  -1.3  175  46 24   7.8   4.3 | -18.4  -1.1  170  38 19   8.1   4.5
 19500 -17.3   0.9  180  44 22   7.8   4.3 | -17.2   1.0  170  37 19   8.1   4.5
 19000 -16.2   2.8  180  41 21   7.8   4.3 | -16.0   3.2  170  37 19   8.2   4.5
 18500 -15.0   5.0  180  39 20   8.4   4.6 | -14.9   5.2  170  37 19   7.8   4.3
 18000 -13.7   7.3  180  37 19   8.4   4.6 | -13.7   7.3  170  36 19   7.7   4.2
 17500 -12.5   9.5  180  35 18   8.5   4.7 | -12.6   9.3  170  36 18   7.7   4.2
 17000 -11.2  11.8  175  33 17   8.7   4.7 | -11.5  11.3  170  35 18   7.7   4.3
 16500 -10.0  14.0  175  31 16   8.7   4.8 | -10.3  13.5  170  35 18   7.8   4.3
 16000  -8.7  16.3  175  30 15   8.8   4.8 |  -9.2  15.4  170  34 17   7.5   4.1
 15500  -7.4  18.7  175  28 14   8.8   4.8 |  -8.1  17.4  170  33 17   7.5   4.1
 15000  -6.1  21.0  175  26 14   9.0   5.0 |  -7.0  19.4  175  33 17   8.3   4.6
 14500  -4.7  23.5  170  25 13   9.1   5.0 |  -5.7  21.7  175  32 17   8.7   4.8
 14000  -3.4  25.9  170  24 12   9.2   5.0 |  -4.4  24.1  175  32 16   8.7   4.8
 13500  -2.1  28.2  170  23 12   9.2   5.1 |  -3.2  26.2  175  31 16   8.7   4.8
 13000  -0.0  32.0  170  21 11   9.4   5.2 |  -1.2  29.8  180  30 15   9.3   5.1
 12500   1.4  34.5  165  19 10   9.4   5.2 |   0.2  32.4  180  29 15   9.5   5.2
 12000   2.7  36.9  165  18  9   9.4   5.2 |   1.6  34.9  180  28 15   9.3   5.1
 11500   4.1  39.4  165  17  9   9.5   5.2 |   3.0  37.4  180  27 14   9.3   5.1
 11000   5.4  41.7  165  16  8   8.2   4.5 |   4.4  39.9  180  25 13   9.0   4.9
 10500   6.6  43.9  160  14  7   8.4   4.6 |   5.7  42.3  185  24 12   9.0   5.0
 10250   7.3  45.1  160  13  7  10.3   5.7 |   6.4  43.5  185  24 12  10.5   5.8
 10000   8.0  46.4  160  13  7  10.1   5.5 |   7.2  45.0  185  23 12  10.1   5.6
  9750   8.7  47.7  160  12  6   9.1   5.0 |   7.9  46.2  185  22 11   8.8   4.8
  9500   9.4  48.9  165  12  6   9.7   5.3 |   8.6  47.5  190  21 11   9.6   5.3
  9250  10.1  50.2  165  11  6   8.3   4.6 |   9.2  48.6  190  21 11   7.9   4.3
  9000  10.6  51.1  165  11  5   8.7   4.8 |   9.8  49.6  190  20 10   7.4   4.1
  8750  11.4  52.5  165  11  5  10.4   5.7 |  10.4  50.7  195  19 10   8.8   4.8
  8500  12.1  53.8  165  10  5   9.5   5.2 |  11.0  51.8  195  18  9   8.0   4.4
  8250  12.9  55.2  165  10  5  11.3   6.2 |  11.6  52.9  200  17  9   9.6   5.3
  8000  13.7  56.7  165  10  5  10.8   5.9 |  12.4  54.3  200  16  8   9.1   5.0
  7750  14.4  57.9  165  10  5   8.8   4.8 |  13.0  55.4  205  15  8   7.3   4.0
  7500  15.1  59.2  170  10  5   9.3   5.1 |  13.5  56.3  210  14  7   7.6   4.1
  7250  15.8  60.4  170  10  5   9.5   5.2 |  14.1  57.4  215  13  7   8.5   4.7
  7000  16.5  61.7  170  10  5  10.2   5.6 |  14.7  58.5  220  13  6   8.7   4.8
  6750  17.3  63.1  170  10  5  10.4   5.7 |  15.3  59.5  225  12  6   7.4   4.1
  6500  18.1  64.6  170   9  5  10.5   5.8 |  15.9  60.6  230  11  6   7.5   4.1
  6250  18.9  66.0  170   9  5  10.9   6.0 |  16.4  61.5  235  10  5   8.2   4.5
  6000  19.7  67.5  170   9  5  11.1   6.1 |  17.1  62.8  240  10  5   8.5   4.7
  5750  20.5  68.9  175   9  4   9.9   5.4 |  17.7  63.9  245   9  5   8.9   4.9
  5500  21.2  70.2  175   8  4  12.2   6.7 |  18.3  64.9  250   8  4   7.4   4.1
  5250  22.4  72.3  175   8  4  18.4  10.1 |  18.6  65.5  250   8  4   3.2   1.8
  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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