Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281223
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0623 MDT Saturday, March 28, 2015

This forecast is for Saturday, March 28, 2015:

If the trigger temperature of 69.0 F/20.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 926 ft/min (4.7 m/s)
   Maximum height of thermals.................. 15562 ft MSL (10723 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1315 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................. 10945 ft MSL (6105 ft AGL)
Thermal soaring outlook for Sunday 03/29....... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:05:13 / 19:32:49 MDT
Total possible sunshine........... 12 hr 27 min 36 sec (747 min 36 sec)
Altitude of sun at 13:19:10 MDT... 53.98 degrees

Upper air data from rawinsonde observation taken on 03/28/2015 at 0600 MDT

Freezing level.................. 12329 ft MSL (7490 ft AGL)
Convective condensation level... 18977 ft MSL (14138 ft AGL)
Lifted condensation level....... 17566 ft MSL (12727 ft AGL)
Lifted index.................... +1.1
K index......................... +3.3

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  -63.4 -82.1   325   33   17   1.7   0.9   91.5 196.7    37.9      M    M
 45000  -55.3 -67.5   325   36   19   7.5   4.1   80.4 176.7    33.8      M    M
 40000  -48.4 -55.1   325   47   24   6.6   3.6   68.3 155.0    28.1      M    M
 38000  -44.9 -48.8   320   49   25   5.8   3.2   64.6 148.4    26.4      M    M
 36000  -43.8 -46.8   310   50   26   3.3   1.8   56.8 134.2    21.7      M    M
 34000  -48.2 -54.8   310   41   21  -8.9  -4.9   42.3 108.1    11.9      M    M
 32000  -46.4 -51.5   310   40   21   7.6   4.2   36.6  98.0     8.1      M    M
 30000  -41.7 -43.1   310   43   22   7.9   4.4   35.1  95.2     7.2      M    M
 29000  -39.3 -38.7   305   41   21   8.5   4.7   34.4  93.9     6.7      M    M
 28000  -36.7 -34.1   305   39   20   8.5   4.6   33.9  93.0     6.4      M    M
 27000  -34.2 -29.6   300   38   19   8.1   4.5   33.5  92.2     6.1      M    M
 26000  -31.9 -25.4   295   36   19   7.5   4.1   32.7  90.8     5.6      M    M
 25000  -29.3 -20.7   290   35   18   9.0   4.9   32.3  90.1     5.4      M    M
 24000  -26.5 -15.7   295   33   17   9.2   5.0   32.0  89.6     5.2      M    M
 23000  -23.8 -10.8   295   31   16   8.8   4.8   31.8  89.2     5.1      M    M
 22000  -21.1  -6.0   290   29   15   9.5   5.2   31.4  88.6     4.8      M    M
 21000  -18.3  -0.9   290   27   14   9.5   5.2   31.3  88.3     4.8      M    M
 20000  -15.6   3.9   285   25   13   7.2   3.9   31.0  87.8     4.6      M    M
 19500  -14.0   6.8   290   23   12   7.3   4.0   30.4  86.7     4.1      M    M
 19000  -12.8   9.0   290   21   11   8.6   4.7   30.0  86.0     3.8      M    M
 18500  -11.5  11.3   285   20   10   8.8   4.8   29.9  85.7     3.7      M    M
 18000  -10.1  13.8   290   19   10   7.9   4.3   29.7  85.5     3.6      M    M
 17500   -9.2  15.4   305   19   10   5.3   2.9   29.1  84.3     3.1      M    M
 17000   -8.4  16.9   320   20   10   5.4   2.9   28.3  83.0     2.4      M    M
 16500   -7.6  18.3   315   21   11   5.4   3.0   27.6  81.6     1.8      M    M
 16000   -7.1  19.2   310   22   11   2.2   1.2   26.5  79.8     0.8      M    M
 15500   -6.7  19.9   310   19   10   2.4   1.3   25.3  77.6    -0.3    920  4.7
 15000   -6.2  20.8   310   17    9   6.8   3.7   24.4  75.9    -1.2    888  4.5
 14500   -5.1  22.8   295   16    8   7.2   4.0   24.0  75.2    -1.6    841  4.3
 14000   -4.1  24.6   285   15    8   7.3   4.0   23.6  74.5    -2.0    795  4.0
 13500   -3.0  26.6   275   15    8   7.6   4.2   23.2  73.7    -2.4    748  3.8
 13000   -1.9  28.6   270   15    8   9.1   5.0   22.9  73.3    -2.8    700  3.6
 12500   -0.4  31.3   260   18    9   9.5   5.2   22.9  73.2    -2.8    642  3.3
 12000    1.0  33.8   255   21   11   9.6   5.3   22.9  73.2    -2.9    584  3.0
 11500    2.4  36.3   255   20   10   9.6   5.3   22.8  73.1    -2.9    527  2.7
 11000    3.8  38.8   250   19   10   9.6   5.2   22.8  73.1    -3.0    469  2.4
 10500    4.9  40.8   250   17    9   4.7   2.6   22.4  72.3    -3.4    423  2.2
 10250    5.3  41.5   250   17    9   6.7   3.7   22.0  71.7    -3.7    403  2.0
 10000    5.9  42.6   250   17    9   7.6   4.2   21.9  71.4    -3.9    379  1.9
  9750    6.4  43.5   250   16    8   7.4   4.1   21.7  71.0    -4.1    355  1.8
  9500    7.0  44.6   250   15    8   7.5   4.1   21.5  70.7    -4.3    331  1.7
  9250    7.5  45.5   255   13    7   7.4   4.1   21.3  70.4    -4.5    308  1.6
  9000    8.1  46.6   255   12    6   7.4   4.1   21.2  70.1    -4.7    284  1.4
  8750    8.6  47.5   255   11    6   7.4   4.1   21.0  69.8    -4.9    260  1.3
  8500    9.2  48.6   260   10    5   7.5   4.1   20.8  69.4    -5.1    236  1.2
  8250    9.7  49.5   265    9    5   7.5   4.1   20.6  69.1    -5.2    212  1.1
  8000   10.3  50.5   270    8    4   7.5   4.1   20.4  68.8    -5.4    188  1.0
  7750   10.8  51.4   265    7    3   7.4   4.1   20.3  68.5    -5.6    164  0.8
  7500   11.4  52.5   255    5    2   7.5   4.1   20.1  68.1    -5.8    140  0.7
  7250   11.9  53.4   235    3    2   7.3   4.0   19.9  67.8    -6.0    116  0.6
  7000   12.5  54.5   200    3    2   8.2   4.5   19.7  67.5    -6.2     92  0.5
  6750   13.0  55.4   165    5    3   4.1   2.3   19.5  67.1    -6.4     69  0.3
  6500   13.1  55.6   155    9    5   1.3   0.7   18.9  66.0    -7.1     58  0.3
  6250   13.2  55.8   155   13    7  -3.4  -1.9   18.2  64.7    -7.8     49  0.3
  6000   12.6  54.7   150   17    9  -9.2  -5.1   16.8  62.3    -9.1     60  0.3
  5750   12.0  53.6   145   17    9  -6.7  -3.7   15.5  59.9   -10.5     70  0.4
  5500   11.6  52.9   140   16    8  -0.9  -0.5   14.4  58.0   -11.6     73  0.4
  5250   11.7  53.1   135   14    7   1.5   0.8   13.8  56.9   -12.2     62  0.3
  5000   11.4  52.5   125   13    7 -14.9  -8.2   12.7  54.9   -13.4     66  0.3

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

           03/28/2015 at 0900 MDT          |       03/28/2015 at 1200 MDT
                                           |
K index... +1.2  LI... +4.1                | K index... +7.2  LI... +3.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.9
                                           |
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 -62.5 -80.5  310  28 14   4.2   2.3 | -62.4 -80.3  290  26 14   4.2   2.3
 45000 -55.9 -68.6  305  35 18   5.0   2.7 | -55.8 -68.4  290  38 20   5.0   2.8
 40000 -48.4 -55.1  300  37 19   5.1   2.8 | -48.2 -54.8  295  39 20   4.9   2.7
 38000 -46.8 -52.2  300  37 19   2.5   1.4 | -46.5 -51.7  290  39 20   2.8   1.5
 36000 -45.1 -49.2  300  37 19   2.5   1.4 | -44.8 -48.6  285  40 21   2.8   1.5
 34000 -44.3 -47.7  300  36 19   0.5   0.3 | -43.8 -46.8  280  39 20   0.3   0.1
 32000 -44.0 -47.2  300  34 17   0.5   0.3 | -43.6 -46.5  280  35 18   0.2   0.1
 30000 -41.3 -42.3  305  34 17   8.2   4.5 | -41.0 -41.8  280  34 17   8.0   4.4
 29000 -38.9 -38.0  305  35 18   8.2   4.5 | -38.6 -37.5  280  34 17   8.0   4.4
 28000 -36.4 -33.5  310  37 19   8.2   4.5 | -36.1 -33.0  280  34 17   8.0   4.4
 27000 -33.8 -28.8  310  37 19   8.8   4.8 | -33.6 -28.5  280  34 17   9.0   4.9
 26000 -31.2 -24.2  305  35 18   8.9   4.9 | -30.8 -23.4  280  33 17   9.0   5.0
 25000 -28.5 -19.3  305  34 18   8.9   4.9 | -28.1 -18.6  280  33 17   9.0   5.0
 24000 -25.9 -14.6  300  32 17   8.5   4.6 | -25.5 -13.9  280  32 16   8.0   4.4
 23000 -23.3  -9.9  295  30 16   8.5   4.7 | -23.1  -9.6  280  29 15   8.1   4.4
 22000 -20.8  -5.4  295  28 15   8.5   4.6 | -20.7  -5.3  280  27 14   8.1   4.4
 21000 -18.4  -1.1  295  26 14   7.7   4.2 | -18.4  -1.1  280  26 13   7.4   4.0
 20000 -15.5   4.1  290  24 12   7.7   4.2 | -16.2   2.8  280  26 13   7.4   4.0
 19500 -14.3   6.3  290  23 12   7.7   4.2 | -15.1   4.8  280  26 13   7.3   4.0
 19000 -13.2   8.2  290  23 12   7.0   3.8 | -14.0   6.8  280  26 13   7.0   3.9
 18500 -12.2  10.0  295  22 11   6.7   3.7 | -13.0   8.6  280  25 13   6.1   3.4
 18000 -11.2  11.8  295  21 11   6.7   3.7 | -12.1  10.2  280  24 12   6.2   3.4
 17500 -10.3  13.5  295  20 10   6.3   3.4 | -11.2  11.8  280  22 11   6.2   3.4
 17000  -9.3  15.3  300  19 10   6.3   3.4 | -10.3  13.5  280  20 11   6.2   3.4
 16500  -8.4  16.9  300  18 10   6.3   3.5 |  -9.3  15.3  280  19 10   6.4   3.5
 16000  -7.5  18.5  300  18  9   6.4   3.5 |  -8.4  16.9  285  17  9   6.7   3.7
 15500  -6.5  20.3  305  17  9   6.5   3.5 |  -6.9  19.6  290  15  8   6.9   3.8
 15000  -5.6  21.9  305  17  9   6.5   3.6 |  -5.9  21.4  295  15  8   7.0   3.9
 14500  -4.6  23.7  305  17  9   6.8   3.7 |  -4.9  23.2  295  14  7   7.9   4.4
 14000  -3.5  25.7  300  17  9   7.7   4.3 |  -3.6  25.5  300  14  7   9.1   5.0
 13500  -2.4  27.7  300  16  8   7.7   4.2 |  -2.2  28.0  300  14  7   9.1   5.0
 13000  -1.2  29.8  295  16  8   7.7   4.2 |  -0.9  30.4  300  13  7   8.9   4.9
 12500  -0.1  31.8  290  16  8   7.8   4.3 |   0.4  32.7  300  13  7   8.8   4.9
 12000   1.0  33.8  285  16  8   8.5   4.7 |   1.7  35.1  295  13  7   8.5   4.7
 11500   2.3  36.1  280  16  8   8.5   4.7 |   3.0  37.4  290  12  6   8.4   4.6
 11000   3.5  38.3  275  17  9   8.7   4.8 |   4.2  39.6  280  13  6   7.8   4.3
 10500   4.8  40.6  270  17  9   8.8   4.8 |   5.4  41.7  275  13  7   5.3   2.9
 10250   5.3  41.5  265  18  9   4.9   2.7 |   5.7  42.3  275  13  7   4.8   2.6
 10000   5.6  42.1  265  17  9   6.9   3.8 |   6.2  43.2  270  14  7   9.5   5.2
  9750   6.4  43.5  265  17  9  11.5   6.3 |   7.0  44.6  270  14  7  10.4   5.7
  9500   7.2  45.0  265  17  9  10.0   5.5 |   7.7  45.9  265  15  8   9.0   4.9
  9250   7.9  46.2  265  16  8   7.3   4.0 |   8.3  46.9  265  15  8   6.8   3.7
  9000   8.3  46.9  265  15  8   5.6   3.1 |   8.7  47.7  265  15  8   7.2   4.0
  8750   8.8  47.8  265  14  7   6.6   3.6 |   9.4  48.9  265  14  7   8.7   4.8
  8500   9.2  48.6  260  12  6   5.8   3.2 |  10.0  50.0  260  13  7   6.2   3.4
  8250   9.6  49.3  260  10  5   4.5   2.5 |  10.3  50.5  260  11  6   3.8   2.1
  8000   9.9  49.8  255   8  4   4.0   2.2 |  10.6  51.1  255   9  5   4.0   2.2
  7750  10.2  50.4  245   7  3   3.7   2.0 |  10.9  51.6  250   7  4   3.8   2.1
  7500  10.5  50.9  230   5  3   3.3   1.8 |  11.2  52.2  240   5  3   4.7   2.6
  7250  10.7  51.3  210   6  3   3.0   1.7 |  11.5  52.7  235   5  2   5.1   2.8
  7000  10.9  51.6  195   6  3   3.3   1.8 |  11.8  53.2  225   4  2   5.7   3.1
  6750  11.2  52.2  185   7  4   2.5   1.4 |  12.3  54.1  215   4  2   8.9   4.9
  6500  11.3  52.3  175   8  4  -0.4  -0.2 |  13.1  55.6  215   4  2  10.8   5.9
  6250  11.1  52.0  165   7  4  -2.2  -1.2 |  13.9  57.0  215   4  2  10.9   6.0
  6000  11.0  51.8  155   7  3  -0.3  -0.2 |  14.7  58.5  215   4  2  10.0   5.5
  5750  10.9  51.6  145   7  3  -5.9  -3.2 |  15.4  59.7  220   4  2  11.0   6.0
  5500   9.9  49.8  135   5  3 -16.5  -9.1 |  16.3  61.3  220   3  2  13.1   7.2
  5250     M     M    M   M  M     M     M |  17.3  63.1  220   3  2  11.4   6.3
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/28/2015 at 1500 MDT          |       03/28/2015 at 1800 MDT
                                           |
K index... +8.0  LI... +2.1                | K index... +6.9  LI... +1.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.0
                                           |
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 -62.2 -80.0  280  27 14   3.7   2.0 | -61.9 -79.4  270  37 19   3.3   1.8
 45000 -56.1 -69.0  290  39 20   5.6   3.1 | -56.2 -69.2  280  39 20   5.8   3.2
 40000 -47.3 -53.1  285  43 22   4.2   2.3 | -47.5 -53.5  275  47 24   6.0   3.3
 38000 -45.8 -50.4  280  44 23   2.4   1.3 | -46.0 -50.8  275  49 25   2.2   1.2
 36000 -44.4 -47.9  275  46 24   2.4   1.3 | -44.6 -48.3  270  51 26   2.2   1.2
 34000 -43.7 -46.7  275  46 23  -0.2  -0.1 | -43.9 -47.0  270  52 27  -0.1  -0.1
 32000 -43.8 -46.8  270  43 22  -0.2  -0.1 | -43.9 -47.0  270  48 25  -0.1  -0.0
 30000 -41.5 -42.7  270  42 21   8.7   4.8 | -41.4 -42.5  270  46 24   8.5   4.7
 29000 -38.9 -38.0  270  41 21   8.7   4.8 | -38.8 -37.8  270  45 23   8.5   4.7
 28000 -36.3 -33.3  270  41 21   8.7   4.8 | -36.2 -33.2  270  44 22   8.5   4.6
 27000 -33.7 -28.7  270  40 20   8.7   4.8 | -33.9 -29.0  270  42 21   7.0   3.8
 26000 -30.4 -22.7  265  38 19   8.7   4.8 | -31.8 -25.2  270  39 20   7.0   3.8
 25000 -27.8 -18.0  265  36 19   8.6   4.7 | -29.7 -21.5  275  36 19   7.0   3.8
 24000 -25.5 -13.9  265  34 17   6.9   3.8 | -27.5 -17.5  275  34 17   8.5   4.7
 23000 -23.4 -10.1  270  30 16   6.9   3.8 | -25.0 -13.0  275  32 17   8.4   4.6
 22000 -21.4  -6.5  275  27 14   6.9   3.8 | -22.4  -8.3  275  30 16   8.4   4.6
 21000 -19.1  -2.4  280  26 14   8.3   4.5 | -20.0  -4.0  280  29 15   7.9   4.3
 20000 -16.6   2.1  280  27 14   8.3   4.5 | -17.6   0.3  285  29 15   7.9   4.3
 19500 -15.4   4.3  280  28 14   8.2   4.5 | -16.4   2.5  290  29 15   7.9   4.3
 19000 -14.1   6.6  285  28 14   7.7   4.2 | -15.3   4.5  290  29 15   8.0   4.4
 18500 -13.1   8.4  285  27 14   7.0   3.8 | -14.1   6.6  295  29 15   8.2   4.5
 18000 -12.0  10.4  280  27 14   7.1   3.9 | -12.9   8.8  295  28 14   8.2   4.5
 17500 -11.1  12.0  280  26 13   5.8   3.2 | -11.7  10.9  295  27 14   7.9   4.4
 17000 -10.2  13.6  280  24 12   5.9   3.2 | -10.5  13.1  295  26 13   7.9   4.4
 16500  -9.3  15.3  275  23 12   6.6   3.6 |  -9.3  15.3  295  24 12   8.1   4.5
 16000  -8.3  17.1  270  22 11   7.1   3.9 |  -8.1  17.4  290  23 12   8.4   4.6
 15500  -7.3  18.9  270  21 11   7.3   4.0 |  -6.2  20.8  285  20 10   8.6   4.7
 15000  -6.1  21.0  270  20 10   8.2   4.5 |  -4.9  23.2  280  19 10   8.7   4.7
 14500  -4.9  23.2  265  18 10   8.2   4.5 |  -3.6  25.5  275  19 10   8.6   4.7
 14000  -3.7  25.3  265  17  9   8.8   4.8 |  -2.3  27.9  270  19 10   8.6   4.7
 13500  -2.4  27.7  265  16  8   8.8   4.8 |  -1.1  30.0  265  19 10   8.6   4.7
 13000  -0.5  31.1  265  15  8   8.9   4.9 |   0.2  32.4  265  19 10   8.7   4.8
 12500   0.9  33.6  260  15  8   9.0   4.9 |   1.6  34.9  260  19 10   8.7   4.8
 12000   2.2  36.0  260  15  8   9.2   5.0 |   2.9  37.2  260  19 10   9.1   5.0
 11500   3.6  38.5  260  15  8   9.1   5.0 |   4.2  39.6  260  19 10   9.1   5.0
 11000   4.9  40.8  260  15  8   8.4   4.6 |   5.6  42.1  260  19 10   8.6   4.7
 10500   6.2  43.2  260  15  8   4.8   2.6 |   6.9  44.4  260  19 10   4.9   2.7
 10250   6.4  43.5  265  15  8   5.7   3.1 |   7.1  44.8  260  19 10   5.9   3.2
 10000   7.1  44.8  265  15  8  11.1   6.1 |   7.9  46.2  260  18  9  11.6   6.4
  9750   7.9  46.2  265  15  8   9.9   5.4 |   8.7  47.7  260  18  9  10.3   5.6
  9500   8.6  47.5  265  15  8   9.1   5.0 |   9.4  48.9  260  18  9   9.8   5.4
  9250   9.2  48.6  265  15  8   7.3   4.0 |  10.1  50.2  260  17  9   7.8   4.3
  9000   9.7  49.5  265  14  7   7.7   4.2 |  10.6  51.1  260  17  9   8.3   4.6
  8750  10.3  50.5  265  13  7   8.3   4.6 |  11.3  52.3  260  16  8   9.5   5.2
  8500  10.9  51.6  265  12  6   7.4   4.1 |  12.0  53.6  260  16  8   8.5   4.7
  8250  11.3  52.3  270  11  6   6.1   3.3 |  12.5  54.5  265  14  7   7.4   4.0
  8000  11.8  53.2  270   9  5   7.6   4.2 |  13.1  55.6  265  12  6   7.3   4.0
  7750  12.4  54.3  270   8  4   9.0   4.9 |  13.6  56.5  265  11  5   7.2   3.9
  7500  13.0  55.4  270   8  4   9.3   5.1 |  14.1  57.4  265   9  5   8.3   4.5
  7250  13.8  56.8  270   7  4   9.9   5.4 |  14.8  58.6  265   8  4   9.2   5.1
  7000  14.5  58.1  270   7  4   9.7   5.3 |  15.5  59.9  265   8  4   9.2   5.1
  6750  15.2  59.4  270   7  4  10.3   5.7 |  16.2  61.2  260   8  4  10.0   5.5
  6500  16.0  60.8  270   7  4  11.0   6.0 |  16.9  62.4  260   7  4  10.2   5.6
  6250  16.9  62.4  270   7  4  11.5   6.3 |  17.7  63.9  260   7  4  10.6   5.8
  6000  17.7  63.9  270   7  3  10.2   5.6 |  18.5  65.3  260   7  4   9.4   5.2
  5750  18.4  65.1  270   6  3  11.5   6.3 |  19.1  66.4  260   7  3   8.2   4.5
  5500  19.4  66.9  270   7  3  14.2   7.8 |  19.7  67.5  260   6  3   8.5   4.6
  5250  20.4  68.7  270   7  3  12.0   6.6 |  20.3  68.5  260   6  3   8.3   4.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  Note that some elevations in numerical weather prediction models
differ from actual station elevations, which can lead to data which appear
to be below ground.  Erroneous data such as these should not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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