Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281252
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0652 MDT Thursday, April 28, 2016

This forecast is for Thursday, April 28, 2016:

If the trigger temperature of 52.0 F/11.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 38 ft/min (0.2 m/s)
   Maximum height of thermals.................. 11236 ft MSL (6397 ft AGL)

Forecast maximum temperature................... 59.0 F/15.5 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9258 ft MSL (4419 ft AGL)
Thermal soaring outlook for Friday 04/29....... Good

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

Remarks...

Sunrise/Sunset.................... 06:19:00 / 20:03:51 MDT
Total possible sunshine........... 13 hr 44 min 51 sec (824 min 51 sec)
Altitude of sun at 13:11:36 MDT... 65.35 degrees

Upper air data from rawinsonde observation taken on 04/28/2016 at 0600 MDT

Freezing level.................. 8174 ft MSL (3335 ft AGL)
Convective condensation level... 8901 ft MSL (4062 ft AGL)
Lifted condensation level....... 10442 ft MSL (5602 ft AGL)
Lifted index.................... -0.3
K index......................... +24.4

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  -56.0 -68.8   230   24   12   1.7   0.9  108.7 227.7    53.3      M    M
 45000  -54.9 -66.8   220   29   15  -2.4  -1.3   85.6 186.1    43.0      M    M
 40000  -55.4 -67.7   210   33   17  -4.9  -2.7   61.6 142.8    30.3      M    M
 38000  -56.5 -69.7   215   39   20  -1.9  -1.0   51.1 124.0    24.1      M    M
 36000  -54.2 -65.6   215   45   23  -5.5  -3.0   45.8 114.5    21.2      M    M
 34000  -54.9 -66.8   210   37   19   6.6   3.6   35.4  95.7    14.4      M    M
 32000  -54.7 -66.5   175   26   13  10.3   5.7   27.5  81.5     9.1      M    M
 30000  -48.6 -55.5   175   28   15   7.7   4.2   27.8  82.0     9.5      M    M
 29000  -45.8 -50.4   185   32   16   9.6   5.3   27.5  81.5     9.4      M    M
 28000  -43.0 -45.4   190   36   19   9.6   5.3   27.5  81.5     9.6      M    M
 27000  -40.1 -40.2   185   34   18   9.3   5.1   27.3  81.2     9.6      M    M
 26000  -37.3 -35.1   185   33   17   9.5   5.2   27.3  81.1     9.6      M    M
 25000  -34.5 -30.1   180   31   16   9.2   5.1   27.1  80.8     9.6      M    M
 24000  -31.8 -25.2   185   29   15   9.3   5.1   26.8  80.3     9.5      M    M
 23000  -29.2 -20.6   185   28   14   8.3   4.6   26.4  79.6     9.2      M    M
 22000  -26.7 -16.1   185   27   14   9.0   4.9   25.9  78.7     8.9      M    M
 21000  -24.0 -11.2   185   26   13   8.8   4.8   25.8  78.4     8.8      M    M
 20000  -21.4  -6.5   185   25   13   7.2   4.0   25.4  77.7     8.6      M    M
 19500  -20.4  -4.7   185   25   13   6.9   3.8   24.9  76.7     8.2      M    M
 19000  -19.4  -2.9   180   24   12   6.9   3.8   24.4  75.9     7.8      M    M
 18500  -17.8  -0.0   180   22   11   6.9   3.8   23.6  74.5     7.2      M    M
 18000  -16.8   1.8   185   23   12   7.0   3.8   23.1  73.6     6.8      M    M
 17500  -15.8   3.6   185   23   12   7.0   3.8   22.6  72.7     6.3      M    M
 17000  -14.8   5.4   190   24   12   7.0   3.8   22.1  71.9     5.9      M    M
 16500  -13.7   7.3   195   25   13   7.0   3.9   21.7  71.1     5.6      M    M
 16000  -12.7   9.1   195   26   14   7.0   3.9   21.3  70.3     5.2      M    M
 15500  -11.7  10.9   190   29   15   7.0   3.9   20.8  69.5     4.8      M    M
 15000  -10.7  12.7   190   31   16   6.4   3.5   20.4  68.6     4.4      M    M
 14500   -9.8  14.4   185   28   14   6.0   3.3   19.7  67.5     3.8      M    M
 14000   -8.9  16.0   180   25   13   5.9   3.3   19.1  66.4     3.3      M    M
 13500   -8.1  17.4   180   23   12   6.0   3.3   18.5  65.2     2.6      M    M
 13000   -7.2  19.0   175   21   11   6.0   3.3   17.8  64.1     2.1      M    M
 12500   -6.3  20.7   175   19   10   6.0   3.3   17.2  63.0     1.5      M    M
 12000   -5.5  22.1   170   17    9   6.0   3.3   16.7  62.0     0.9      M    M
 11500   -4.6  23.7   165   16    8   6.0   3.3   16.0  60.8     0.3      M    M
 11000   -3.8  25.2   160   16    8   6.0   3.3   15.4  59.7    -0.3    418  2.1
 10500   -2.9  26.8   155   15    8   6.2   3.4   14.8  58.7    -0.9    378  1.9
 10250   -2.5  27.5   155   15    8   4.8   2.6   14.5  58.1    -1.2    358  1.8
 10000   -2.2  28.0   155   15    8   3.6   2.0   14.0  57.3    -1.7    342  1.7
  9750   -1.9  28.6   150   15    8   4.0   2.2   13.6  56.4    -2.1    326  1.7
  9500   -1.6  29.1   145   16    8   4.1   2.2   13.1  55.6    -2.5    310  1.6
  9250   -1.3  29.7   135   17    9   4.1   2.2   12.7  54.8    -3.0    294  1.5
  9000   -1.0  30.2   130   19   10   4.1   2.2   12.2  54.0    -3.4    277  1.4
  8750   -0.7  30.7   135   19   10   4.0   2.2   11.8  53.2    -3.9    261  1.3
  8500   -0.4  31.3   140   18    9   4.2   2.3   11.3  52.4    -4.3    245  1.2
  8250   -0.1  31.8   145   18    9   3.6   2.0   10.9  51.6    -4.7    229  1.2
  8000    0.2  32.4   150   18    9   5.9   3.2   10.5  50.9    -5.2    212  1.1
  7750    0.7  33.3   150   18    9   8.6   4.7   10.3  50.6    -5.4    188  1.0
  7500    1.4  34.5   150   18    9   8.3   4.6   10.2  50.4    -5.5    162  0.8
  7250    2.0  35.6   155   17    9   8.4   4.6   10.1  50.3    -5.6    136  0.7
  7000    2.6  36.7   155   17    9   8.4   4.6   10.1  50.1    -5.7    110  0.6
  6750    3.2  37.8   155   16    8   8.4   4.6    9.9  49.9    -5.8     84  0.4
  6500    3.8  38.8   150   14    7   8.4   4.6    9.8  49.7    -6.0     58  0.3
  6250    4.4  39.9   150   12    6   8.4   4.6    9.7  49.5    -6.1     32  0.2
  6000    5.0  41.0   145   10    5   8.4   4.6    9.7  49.4    -6.2      7  0.0
  5750    5.7  42.3   140    9    5   8.4   4.6    9.5  49.2    -6.3      M    M
  5500    6.3  43.3   135    7    4   8.4   4.6    9.4  49.0    -6.5      M    M
  5250    6.9  44.4   125    6    3   8.4   4.6    9.3  48.8    -6.6      M    M
  5000    7.5  45.5   110    5    2   8.4   4.6    9.2  48.6    -6.8      M    M

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

           04/28/2016 at 0900 MDT          |       04/28/2016 at 1200 MDT
                                           |
K index... +26.3  LI... +273.2             | K index... +19.1  LI... +271.5
CAPE... +17.1  CIN... -85.6                | CAPE... +286.6  CIN... -21.9
                                           |
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 -54.7 -66.5  235  22 11   1.6   0.9 | -54.6 -66.3  235  25 13   1.5   0.8
 45000 -52.3 -62.1  235  26 13   1.6   0.9 | -52.3 -62.1  235  27 14   1.6   0.9
 40000 -52.3 -62.1  215  30 16  -0.1  -0.1 | -51.5 -60.7  220  34 18   0.4   0.2
 38000 -52.5 -62.5  210  32 17  -0.6  -0.3 | -51.4 -60.5  215  35 18  -0.4  -0.2
 36000 -52.9 -63.2  200  32 17  -0.6  -0.3 | -51.6 -60.9  205  32 16  -0.4  -0.2
 34000 -53.2 -63.8  195  33 17  -0.5  -0.3 | -51.9 -61.4  190  29 15  -0.5  -0.3
 32000 -51.8 -61.2  185  30 15   2.7   1.5 | -50.8 -59.4  160  23 12   2.1   1.1
 30000 -50.2 -58.4  170  28 14   4.3   2.4 | -49.6 -57.3  125  26 13   2.9   1.6
 29000 -47.7 -53.9  170  27 14   9.0   4.9 | -47.3 -53.1  125  27 14   8.4   4.6
 28000 -45.0 -49.0  170  27 14   9.0   4.9 | -44.2 -47.6  125  27 14   8.4   4.6
 27000 -41.6 -42.9  170  27 14   8.9   4.9 | -41.7 -43.1  125  28 14   8.4   4.6
 26000 -38.8 -37.8  170  25 13   9.5   5.2 | -39.2 -38.6  130  27 14   8.3   4.6
 25000 -36.0 -32.8  170  23 12   9.5   5.2 | -36.7 -34.1  140  28 14   8.3   4.6
 24000 -33.2 -27.8  170  21 11   9.5   5.2 | -34.2 -29.6  150  28 15   8.3   4.6
 23000 -30.6 -23.1  170  19 10   8.5   4.7 | -31.7 -25.1  160  28 15   8.3   4.5
 22000 -28.0 -18.4  180  18  9   8.5   4.7 | -29.3 -20.7  170  28 14   8.3   4.5
 21000 -25.5 -13.9  185  18  9   8.5   4.7 | -26.8 -16.2  180  28 15   8.3   4.5
 20000 -23.1  -9.6  195  18  9   7.9   4.3 | -24.4 -11.9  185  28 14   7.8   4.3
 19500 -22.0  -7.6  195  18  9   7.9   4.3 | -23.2  -9.8  185  27 14   7.9   4.3
 19000 -20.8  -5.4  200  19 10   7.9   4.4 | -22.0  -7.6  190  27 14   7.9   4.3
 18500 -19.6  -3.3  200  19 10   8.0   4.4 | -20.9  -5.6  195  27 14   8.0   4.4
 18000 -18.5  -1.3  205  20 10   7.5   4.1 | -19.8  -3.6  195  27 14   6.9   3.8
 17500 -17.4   0.7  205  20 10   7.5   4.1 | -18.7  -1.7  195  27 14   7.0   3.8
 17000 -16.3   2.7  205  21 11   7.3   4.0 | -17.7   0.1  200  27 14   7.1   3.9
 16500 -15.3   4.5  205  22 11   7.1   3.9 | -16.6   2.1  200  27 14   7.2   4.0
 16000 -14.2   6.4  210  23 12   7.1   3.9 | -15.6   3.9  200  27 14   7.3   4.0
 15500 -13.2   8.2  210  24 12   7.2   3.9 | -14.5   5.9  200  27 14   7.1   3.9
 15000 -12.1  10.2  210  24 12   7.2   4.0 | -13.5   7.7  205  27 14   7.0   3.9
 14500 -11.1  12.0  210  25 13   6.6   3.6 | -12.4   9.7  205  27 14   8.1   4.5
 14000 -10.1  13.8  210  25 13   6.6   3.6 | -11.2  11.8  210  27 14   8.1   4.4
 13500  -9.2  15.4  210  25 13   6.8   3.7 |  -9.4  15.1  215  27 14   8.6   4.7
 13000  -7.7  18.1  215  25 13   6.8   3.7 |  -8.1  17.4  220  27 14   8.6   4.7
 12500  -6.7  19.9  215  25 13   6.4   3.5 |  -6.8  19.8  220  28 14   8.6   4.7
 12000  -5.8  21.6  215  26 13   6.4   3.5 |  -5.6  21.9  220  28 14   8.7   4.8
 11500  -4.9  23.2  215  26 14   6.8   3.7 |  -4.4  24.1  220  27 14   8.3   4.5
 11000  -3.9  25.0  215  27 14   6.8   3.7 |  -3.2  26.2  220  26 13   8.3   4.6
 10500  -2.9  26.8  215  28 14   6.2   3.4 |  -2.1  28.2  220  24 12   7.4   4.0
 10250  -2.5  27.5  215  28 14   6.6   3.6 |  -1.5  29.3  220  23 12   8.0   4.4
 10000  -2.0  28.4  215  28 15   7.2   3.9 |  -0.9  30.4  220  22 11   8.5   4.7
  9750  -1.5  29.3  215  28 14   6.7   3.7 |  -0.3  31.5  220  20 10   7.2   3.9
  9500  -1.0  30.2  210  27 14   6.2   3.4 |   0.1  32.2  215  18  9   6.3   3.4
  9250  -0.5  31.1  210  27 14   6.7   3.6 |   0.6  33.1  215  16  8   6.7   3.7
  9000  -0.1  31.8  210  26 13   5.2   2.9 |   1.0  33.8  210  14  7   5.6   3.0
  8750   0.2  32.4  210  24 13   3.7   2.0 |   1.3  34.3  210  13  7   4.4   2.4
  8500   0.5  32.9  205  22 12   4.0   2.2 |   1.7  35.1  210  11  6   4.6   2.5
  8250   0.8  33.4  205  20 10   3.8   2.1 |   2.0  35.6  205   9  5   4.2   2.3
  8000   1.0  33.8  200  18  9   4.4   2.4 |   2.3  36.1  195   7  4   5.9   3.2
  7750   1.3  34.3  200  16  8   3.9   2.1 |   2.7  36.9  200   5  3   6.3   3.5
  7500   1.6  34.9  195  14  7   3.0   1.6 |   3.1  37.6  200   3  2   4.9   2.7
  7250   1.8  35.2  190  12  6   3.2   1.8 |   3.5  38.3  205   1  1   5.6   3.1
  7000   2.0  35.6  185   9  5   3.0   1.6 |   3.9  39.0  000   0  0   7.6   4.2
  6750   2.2  36.0  175   7  4   3.0   1.7 |   4.6  40.3  340   1  1   9.4   5.2
  6500   2.4  36.3  165   5  2   2.6   1.4 |   5.2  41.4  345   2  1   9.2   5.1
  6250   2.7  36.9  135   3  1   4.3   2.4 |   5.9  42.6  345   2  1  10.1   5.5
  6000   3.1  37.6  105   2  1   6.5   3.6 |   6.7  44.1  340   3  1  10.9   6.0
  5750   3.6  38.5  080   2  1   7.4   4.1 |   7.5  45.5  340   3  1   9.7   5.3
  5500   4.1  39.4  065   2  1   7.9   4.3 |   8.2  46.8  340   3  1  10.9   6.0
  5250   4.7  40.5  065   2  1   6.2   3.4 |   9.2  48.6  335   3  2  15.7   8.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/28/2016 at 1500 MDT          |       04/28/2016 at 1800 MDT
                                           |
K index... +24.3  LI... +271.4             | K index... +21.3  LI... +270.9
CAPE... +271.2  CIN... -10.4               | CAPE... +234.8  CIN... -70.8
                                           |
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 -54.6 -66.3  235  25 13   1.2   0.7 | -54.7 -66.5  235  23 12   1.1   0.6
 45000 -52.7 -62.9  230  28 15   1.2   0.7 | -53.0 -63.4  230  28 14   1.1   0.6
 40000 -51.4 -60.5  220  33 17   0.8   0.4 | -51.9 -61.4  220  29 15   0.7   0.4
 38000 -51.2 -60.2  215  33 17  -0.6  -0.3 | -51.6 -60.9  215  30 15  -0.3  -0.2
 36000 -51.6 -60.9  210  30 15  -0.6  -0.4 | -51.8 -61.2  210  29 15  -0.3  -0.2
 34000 -52.0 -61.6  200  28 14  -0.7  -0.4 | -52.0 -61.6  205  30 15  -0.3  -0.2
 32000 -50.4 -58.7  190  20 11   2.9   1.6 | -50.6 -59.1  190  24 12   2.6   1.4
 30000 -48.7 -55.7  170  14  7   3.5   1.9 | -48.7 -55.7  170  18  9   6.6   3.6
 29000 -46.2 -51.2  165  12  6   7.1   3.9 | -46.4 -51.5  165  15  8   7.5   4.1
 28000 -44.1 -47.4  170  11  6   7.1   3.9 | -44.2 -47.6  155  12  6   7.5   4.1
 27000 -41.9 -43.4  170   9  5   7.0   3.9 | -41.9 -43.4  145   9  5   7.4   4.1
 26000 -39.5 -39.1  185  10  5   8.5   4.7 | -39.4 -38.9  160  12  6   8.9   4.9
 25000 -37.0 -34.6  195  13  7   8.5   4.7 | -36.7 -34.1  175  17  9   8.9   4.9
 24000 -34.4 -29.9  205  16  8   8.5   4.7 | -34.0 -29.2  180  24 12   9.0   4.9
 23000 -31.9 -25.4  210  19 10   8.4   4.6 | -31.5 -24.7  185  28 15   8.2   4.5
 22000 -29.4 -20.9  210  24 12   8.4   4.6 | -29.0 -20.2  190  32 17   8.2   4.5
 21000 -26.9 -16.4  215  28 15   8.4   4.6 | -26.6 -15.9  195  37 19   8.2   4.5
 20000 -24.5 -12.1  210  32 17   7.9   4.3 | -24.4 -11.9  200  38 20   7.1   3.9
 19500 -23.3  -9.9  210  34 17   7.9   4.3 | -23.4 -10.1  200  39 20   7.1   3.9
 19000 -22.2  -8.0  210  36 18   7.9   4.3 | -22.3  -8.1  200  39 20   7.1   3.9
 18500 -21.0  -5.8  210  38 19   7.9   4.4 | -21.3  -6.3  200  40 20   7.0   3.8
 18000 -19.8  -3.6  205  39 20   7.8   4.3 | -20.1  -4.2  205  39 20   8.4   4.6
 17500 -18.7  -1.7  205  39 20   7.8   4.3 | -18.9  -2.0  205  38 19   8.3   4.6
 17000 -17.5   0.5  200  40 21   7.9   4.3 | -17.7   0.1  205  36 19   8.9   4.9
 16500 -16.4   2.5  200  39 20   7.9   4.4 | -16.3   2.7  205  34 18   9.2   5.1
 16000 -15.2   4.6  200  37 19   7.9   4.4 | -14.9   5.2  205  33 17   9.3   5.1
 15500 -14.1   6.6  195  36 18   7.7   4.3 | -13.6   7.5  205  31 16   9.2   5.0
 15000 -12.9   8.8  195  34 17   7.8   4.3 | -12.2  10.0  205  29 15   9.2   5.1
 14500 -11.8  10.8  190  32 16   7.9   4.3 | -10.9  12.4  205  27 14   9.2   5.1
 14000 -10.6  12.9  190  30 15   7.9   4.4 |  -8.8  16.2  200  24 13   9.2   5.0
 13500  -8.9  16.0  185  27 14   7.5   4.1 |  -7.5  18.5  200  23 12   9.1   5.0
 13000  -7.8  18.0  185  25 13   7.5   4.1 |  -6.1  21.0  195  21 11   9.0   4.9
 12500  -6.7  19.9  180  23 12   7.3   4.0 |  -4.9  23.2  195  20 10   8.0   4.4
 12000  -5.7  21.7  180  21 11   7.3   4.0 |  -3.7  25.3  190  18  9   8.0   4.4
 11500  -4.5  23.9  175  19 10   8.1   4.4 |  -2.6  27.3  185  17  9   7.5   4.1
 11000  -3.4  25.9  175  17  9   8.0   4.4 |  -1.5  29.3  180  15  8   7.5   4.1
 10500  -2.2  28.0  170  15  8   7.7   4.2 |  -0.5  31.1  170  13  7   6.4   3.5
 10250  -1.6  29.1  170  14  7   8.2   4.5 |  -0.0  32.0  165  12  6   7.2   3.9
 10000  -1.0  30.2  170  13  7   8.6   4.7 |   0.5  32.9  165  11  6   7.7   4.2
  9750  -0.4  31.3  165  12  6   8.0   4.4 |   1.1  34.0  160  10  5   6.5   3.6
  9500   0.2  32.4  160  10  5   7.7   4.2 |   1.5  34.7  150   8  4   6.0   3.3
  9250   0.7  33.3  155   8  4   7.8   4.3 |   1.9  35.4  135   6  3   5.8   3.2
  9000   1.3  34.3  145   6  3   7.6   4.2 |   2.3  36.1  110   5  2   5.3   2.9
  8750   1.8  35.2  140   5  3   7.5   4.1 |   2.7  36.9  085   4  2   6.1   3.3
  8500   2.4  36.3  130   4  2   7.9   4.3 |   3.2  37.8  060   5  2   7.0   3.8
  8250   2.9  37.2  110   3  2   6.9   3.8 |   3.6  38.5  040   6  3   6.0   3.3
  8000   3.4  38.1  075   3  1  10.6   5.8 |   4.1  39.4  030   7  4   9.3   5.1
  7750   4.4  39.9  070   2  1  11.4   6.3 |   4.9  40.8  025   7  3  10.5   5.8
  7500   5.0  41.0  060   2  1   8.3   4.6 |   5.6  42.1  020   7  3   8.3   4.5
  7250   5.7  42.3  050   2  1   9.4   5.2 |   6.2  43.2  020   7  3   8.9   4.9
  7000   6.4  43.5  045   3  1  10.0   5.5 |   6.9  44.4  015   7  3   9.3   5.1
  6750   7.2  45.0  035   2  1  10.3   5.6 |   7.6  45.7  015   6  3   9.8   5.4
  6500   7.9  46.2  030   3  1  10.0   5.5 |   8.3  46.9  015   6  3   9.8   5.4
  6250   8.7  47.7  025   3  1  10.3   5.7 |   9.1  48.4  010   6  3   9.9   5.4
  6000   9.5  49.1  020   3  1  10.7   5.9 |   9.8  49.6  010   6  3  10.0   5.5
  5750  10.3  50.5  015   3  1  10.2   5.6 |  10.5  50.9  010   6  3  10.0   5.5
  5500  11.0  51.8  010   3  1  11.3   6.2 |  11.3  52.3  010   6  3  10.0   5.5
  5250  12.0  53.6  005   3  1  15.3   8.4 |  12.0  53.6  005   6  3   9.6   5.3
  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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