Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 170205
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
2005 MDT Wednesday, April 16, 2014

This forecast is for Thursday, April 17, 2014:

If the trigger temperature of 53.1 F/11.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 705 ft/min (3.6 m/s)
   Maximum height of thermals.................. 15173 ft MSL (10149 ft AGL)

Forecast maximum temperature................... 66.0 F/19.3 C
Time of trigger temperature.................... 1000 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13467 ft MSL (8443 ft AGL)
Thermal soaring outlook for Friday 04/18....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:34:30 / 19:52:34 MDT
Total possible sunshine........... 13 hr 18 min 5 sec (798 min 5 sec)
Altitude of sun at 13:13:41 MDT... 61.54 degrees

Upper air data from numerical model forecast valid on 04/17/2014 at 0600 MDT

Freezing level.................. 5041 ft MSL (17 ft AGL)
Additional freezing level....... 9335 ft MSL (4311 ft AGL)
Convective condensation level... 17205 ft MSL (12181 ft AGL)
Lifted condensation level....... 16126 ft MSL (11103 ft AGL)
Lifted index.................... +3.3
K index......................... +1.3

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  -58.5 -73.3   315   29   15   0.3   0.1      M     M       M      M    M
 45000  -58.1 -72.6   315   41   21   0.8   0.4      M     M       M      M    M
 40000  -63.6 -82.5   330   69   35  -3.7  -2.0      M     M       M      M    M
 38000  -62.6 -80.7   335   74   38   6.7   3.7      M     M       M      M    M
 36000  -58.6 -73.5   330   73   37   6.7   3.7      M     M       M      M    M
 34000  -54.4 -65.9   330   71   36   8.4   4.6      M     M       M      M    M
 32000  -49.4 -56.9   330   66   34   8.3   4.6      M     M       M      M    M
 30000  -44.4 -47.9   330   62   32   8.6   4.7   31.6  88.9     9.6      M    M
 29000  -41.8 -43.2   330   61   31   8.6   4.7   31.1  87.9     9.2      M    M
 28000  -39.3 -38.7   330   59   31   8.6   4.7   30.6  87.1     9.0      M    M
 27000  -36.7 -34.1   330   58   30   8.4   4.6   30.3  86.6     8.9      M    M
 26000  -33.7 -28.7   330   53   27   8.1   4.4   29.4  84.9     8.3      M    M
 25000  -31.3 -24.3   325   48   25   8.1   4.4   28.8  83.8     7.9      M    M
 24000  -28.9 -20.0   325   44   22   7.8   4.3   28.3  82.9     7.6      M    M
 23000  -26.6 -15.9   325   40   21   7.6   4.2   27.4  81.3     6.9      M    M
 22000  -24.4 -11.9   320   37   19   7.6   4.2   26.6  79.9     6.4      M    M
 21000  -22.1  -7.8   320   35   18   7.4   4.0   25.9  78.6     5.8      M    M
 20000  -19.9  -3.8   315   33   17   7.4   4.0   25.0  77.0     5.1      M    M
 19500  -18.8  -1.8   315   33   17   7.4   4.0   24.6  76.3     4.8      M    M
 19000  -17.7   0.1   315   32   17   7.4   4.0   24.2  75.6     4.5      M    M
 18500  -16.7   1.9   315   32   16   5.9   3.3   23.8  74.8     4.1      M    M
 18000  -15.9   3.4   310   31   16   5.3   2.9   23.0  73.4     3.5      M    M
 17500  -15.1   4.8   310   30   15   5.2   2.9   22.2  72.0     2.8      M    M
 17000  -14.3   6.3   310   29   15   5.7   3.1   21.5  70.7     2.2      M    M
 16500  -13.5   7.7   305   27   14   5.6   3.1   20.8  69.4     1.6      M    M
 16000  -12.6   9.3   305   26   13   6.1   3.4   20.1  68.2     1.0      M    M
 15500  -11.7  10.9   305   24   12   6.2   3.4   19.5  67.1     0.4      M    M
 15000  -10.8  12.6   300   22   11   5.2   2.9   18.9  66.1    -0.1    797  4.1
 14500  -10.1  13.8   300   20   11   4.5   2.5   18.0  64.5    -0.9    763  3.9
 14000   -9.5  14.9   300   19   10   4.2   2.3   17.2  62.9    -1.7    730  3.7
 13500   -9.0  15.8   295   17    9   3.6   2.0   16.2  61.1    -2.7    699  3.6
 13000   -8.1  17.4   290   14    7   5.5   3.0   14.8  58.6    -4.1    652  3.3
 12500   -7.3  18.9   285   12    6   5.9   3.2   14.2  57.5    -4.7    611  3.1
 12000   -6.3  20.7   275   10    5   7.6   4.2   13.6  56.5    -5.3    569  2.9
 11500   -5.1  22.8   270    9    4   8.1   4.4   13.4  56.0    -5.5    518  2.6
 11000   -3.9  25.0   265    8    4   8.3   4.5   13.1  55.6    -5.8    467  2.4
 10500   -2.7  27.1   255    7    4   8.9   4.9   12.9  55.1    -6.1    415  2.1
 10250   -2.1  28.2   250    7    4   5.6   3.1   12.7  54.9    -6.2    389  2.0
 10000   -1.7  28.9   245    7    3   6.5   3.6   12.3  54.2    -6.6    372  1.9
  9750   -1.0  30.2   240    6    3  10.2   5.6   12.3  54.1    -6.6    343  1.7
  9500   -0.3  31.5   235    6    3   9.7   5.3   12.3  54.1    -6.7    315  1.6
  9250    0.4  32.7   230    6    3   7.8   4.3   12.3  54.1    -6.7    286  1.5
  9000    0.9  33.6   225    6    3   6.5   3.5   12.0  53.6    -7.0    264  1.3
  8750    1.4  34.5   215    6    3   7.8   4.3   11.8  53.3    -7.2    240  1.2
  8500    2.0  35.6   210    6    3   7.6   4.2   11.7  53.0    -7.4    216  1.1
  8250    2.5  36.5   205    6    3   6.2   3.4   11.5  52.6    -7.6    192  1.0
  8000    2.9  37.2   195    6    3   4.3   2.3   11.1  52.0    -7.9    173  0.9
  7750    3.2  37.8   190    6    3   2.9   1.6   10.6  51.2    -8.4    158  0.8
  7500    3.4  38.1   185    5    3   3.6   2.0   10.1  50.2    -9.0    145  0.7
  7250    3.8  38.8   175    5    3   5.8   3.2    9.7  49.5    -9.4    127  0.6
  7000    4.2  39.6   170    5    3   6.2   3.4    9.5  49.0    -9.7    106  0.5
  6750    4.7  40.5   165    6    3   6.6   3.6    9.2  48.6   -10.0     85  0.4
  6500    5.0  41.0   155    7    3  -0.6  -0.4    8.8  47.8   -10.4     68  0.3
  6250    4.5  40.1   145    6    3  -7.7  -4.2    7.6  45.7   -11.6     74  0.4
  6000    4.1  39.4   130    6    3  -2.0  -1.1    6.5  43.6   -12.8     80  0.4
  5750    3.9  39.0   115    7    3  -7.3  -4.0    5.6  42.1   -13.7     78  0.4
  5500    2.8  37.0   105    6    3 -19.4 -10.6    4.0  39.3   -15.3    104  0.5
  5250    1.3  34.3   100    6    3 -16.2  -8.9    2.2  36.0   -17.2    140  0.7
  5000      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/17/2014 at 0900 MDT          |       04/17/2014 at 1200 MDT
                                           |
K index... +0.2  LI... +7.3                | K index... +4.0  LI... +7.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.0 -74.2  315  28 14  -0.3  -0.2 | -59.9 -75.8  310  27 14  -0.0  -0.0
 45000 -59.4 -74.9  320  40 21  -0.1  -0.1 | -59.9 -75.8  320  35 18  -0.2  -0.1
 40000 -64.5 -84.1  330  63 33  -3.4  -1.9 | -65.2 -85.4  330  58 30  -3.6  -2.0
 38000 -62.9 -81.2  330  67 35   7.6   4.2 | -63.3 -81.9  335  60 31   8.1   4.5
 36000 -58.4 -73.1  330  68 35   7.6   4.2 | -58.4 -73.1  335  57 29   8.1   4.5
 34000 -53.7 -64.7  325  68 35   8.5   4.6 | -53.4 -64.1  330  54 28   9.0   4.9
 32000 -48.6 -55.5  330  64 33   8.5   4.6 | -48.0 -54.4  330  52 27   9.0   4.9
 30000 -43.5 -46.3  330  59 31   8.6   4.7 | -42.7 -44.9  330  48 25   8.4   4.6
 29000 -40.9 -41.6  330  57 29   8.7   4.8 | -39.6 -39.3  330  45 23   8.4   4.6
 28000 -38.3 -36.9  330  54 28   8.7   4.8 | -37.1 -34.8  330  43 22   8.4   4.6
 27000 -35.1 -31.2  335  51 26   7.9   4.3 | -34.6 -30.3  330  40 21   8.4   4.6
 26000 -32.8 -27.0  335  47 24   7.9   4.4 | -32.0 -25.6  325  37 19   8.4   4.6
 25000 -30.4 -22.7  335  44 23   7.9   4.4 | -29.5 -21.1  320  34 17   8.4   4.6
 24000 -28.0 -18.4  330  41 21   7.4   4.1 | -27.1 -16.8  315  32 16   7.5   4.1
 23000 -25.9 -14.6  325  38 19   7.3   4.0 | -24.9 -12.8  310  31 16   7.4   4.0
 22000 -23.7 -10.7  320  35 18   7.3   4.0 | -22.7  -8.9  310  30 15   7.4   4.1
 21000 -21.5  -6.7  315  33 17   7.8   4.3 | -20.5  -4.9  310  29 15   7.3   4.0
 20000 -19.2  -2.6  310  32 16   7.8   4.3 | -18.3  -0.9  305  29 15   7.3   4.0
 19500 -18.0  -0.4  310  31 16   7.8   4.3 | -17.2   1.0  305  28 15   7.3   4.0
 19000 -16.9   1.6  305  30 16   7.9   4.3 | -16.1   3.0  305  28 14   7.3   4.0
 18500 -15.8   3.6  305  30 15   6.4   3.5 | -15.1   4.8  305  28 14   7.1   3.9
 18000 -14.9   5.2  305  29 15   6.1   3.3 | -14.0   6.8  305  27 14   7.0   3.9
 17500 -14.0   6.8  305  28 14   6.1   3.3 | -13.0   8.6  305  27 14   6.7   3.7
 17000 -13.0   8.6  305  28 14   6.2   3.4 | -12.1  10.2  305  26 13   5.9   3.3
 16500 -12.1  10.2  305  27 14   6.2   3.4 | -11.2  11.8  305  25 13   6.0   3.3
 16000 -11.2  11.8  305  27 14   6.1   3.3 | -10.4  13.3  305  24 13   5.5   3.0
 15500 -10.3  13.5  305  25 13   6.1   3.3 |  -9.5  14.9  305  23 12   5.6   3.1
 15000  -9.4  15.1  305  24 13   4.2   2.3 |  -8.8  16.2  305  22 11   4.1   2.3
 14500  -9.0  15.8  300  22 11   3.3   1.8 |  -8.2  17.2  300  20 10   3.7   2.0
 14000  -8.5  16.7  300  20 10   3.1   1.7 |  -7.5  18.5  295  17  9   2.7   1.5
 13500  -8.1  17.4  295  17  9   3.1   1.7 |  -7.0  19.4  285  15  8   2.6   1.4
 13000  -7.3  18.9  285  14  7   5.0   2.8 |  -6.5  20.3  275  13  7   5.0   2.8
 12500  -6.5  20.3  275  11  6   5.2   2.9 |  -5.8  21.6  265  12  6   4.9   2.7
 12000  -5.7  21.7  265  10  5   7.2   4.0 |  -4.9  23.2  255  11  6   7.0   3.8
 11500  -4.6  23.7  255   9  5   7.6   4.2 |  -3.9  25.0  245  12  6   7.1   3.9
 11000  -3.4  25.9  240   8  4   7.7   4.2 |  -2.8  27.0  240  12  6   7.7   4.2
 10500  -2.3  27.9  235   8  4   8.3   4.6 |  -1.7  28.9  240  12  6   8.5   4.7
 10250  -1.8  28.8  230   7  4   4.8   2.7 |  -1.1  30.0  240  11  6   4.5   2.5
 10000  -1.5  29.3  225   7  4   5.4   3.0 |  -0.9  30.4  240  11  6   5.5   3.0
  9750  -0.9  30.4  220   7  4   9.1   5.0 |  -0.2  31.6  240  11  5  10.0   5.5
  9500  -0.2  31.6  220   7  4   8.9   4.9 |   0.5  32.9  240  10  5   9.2   5.0
  9250   0.4  32.7  215   7  4   6.1   3.4 |   1.1  34.0  235   9  5   6.6   3.6
  9000   0.7  33.3  210   7  4   5.1   2.8 |   1.5  34.7  240   9  5   5.8   3.2
  8750   1.3  34.3  210   7  4   7.8   4.3 |   2.1  35.8  235   8  4   8.0   4.4
  8500   1.8  35.2  205   7  4   7.1   3.9 |   2.6  36.7  235   7  4   7.4   4.0
  8250   2.3  36.1  200   7  4   4.8   2.6 |   3.2  37.8  230   6  3   7.2   3.9
  8000   2.6  36.7  195   6  3   3.7   2.0 |   3.7  38.7  225   6  3   7.5   4.1
  7750   2.9  37.2  185   6  3   4.3   2.4 |   4.2  39.6  220   5  3   7.8   4.3
  7500   3.2  37.8  180   6  3   5.4   3.0 |   4.8  40.6  215   5  2   8.8   4.8
  7250   3.7  38.7  170   6  3   6.8   3.7 |   5.5  41.9  215   5  2   9.8   5.4
  7000   4.2  39.6  170   6  3   6.8   3.7 |   6.3  43.3  215   5  2   9.6   5.3
  6750   4.7  40.5  165   6  3   6.0   3.3 |   7.0  44.6  215   5  2  10.2   5.6
  6500   5.0  41.0  160   7  3   3.7   2.0 |   7.8  46.0  215   5  2  10.9   6.0
  6250   5.2  41.4  155   6  3   3.0   1.6 |   8.6  47.5  220   5  2  11.9   6.5
  6000   5.4  41.7  145   5  2   2.0   1.1 |   9.4  48.9  220   4  2   9.5   5.2
  5750   5.5  41.9  130   4  2   6.1   3.3 |  10.1  50.2  225   4  2  10.9   6.0
  5500   6.2  43.2  130   4  2  11.4   6.3 |  11.1  52.0  225   4  2  15.0   8.2
  5250   7.0  44.6  130   4  2   7.4   4.0 |  12.1  53.8  225   4  2  11.7   6.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/17/2014 at 1500 MDT          |       04/17/2014 at 1800 MDT
                                           |
K index... +9.0  LI... +5.6                | K index... +11.5  LI... +4.2
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 -60.6 -77.1  310  25 13   0.3   0.1 | -60.7 -77.3  305  23 12  -0.7  -0.4
 45000 -60.3 -76.5  310  32 16  -2.5  -1.4 | -61.8 -79.2  300  33 17  -2.1  -1.1
 40000 -65.0 -85.0  330  44 22  -3.2  -1.8 | -65.3 -85.5  315  34 18  -2.4  -1.3
 38000 -62.8 -81.0  335  42 22   8.0   4.4 | -62.5 -80.5  315  34 17   8.8   4.8
 36000 -58.0 -72.4  340  37 19   8.0   4.4 | -57.2 -71.0  310  33 17   8.8   4.8
 34000 -53.0 -63.4  340  33 17   9.3   5.1 | -51.9 -61.4  310  32 16   8.8   4.8
 32000 -47.4 -53.3  335  30 16   9.3   5.1 | -46.6 -51.9  305  32 17   8.8   4.8
 30000 -41.3 -42.3  325  30 15   8.5   4.7 | -40.9 -41.6  300  32 16   8.3   4.5
 29000 -38.7 -37.7  320  30 16   8.5   4.7 | -38.4 -37.1  300  32 16   8.3   4.5
 28000 -36.2 -33.2  315  31 16   8.5   4.7 | -35.9 -32.6  300  31 16   8.3   4.6
 27000 -33.7 -28.7  310  31 16   8.3   4.5 | -33.4 -28.1  300  31 16   8.3   4.5
 26000 -31.2 -24.2  305  30 15   8.3   4.5 | -30.9 -23.6  300  30 16   8.3   4.5
 25000 -28.7 -19.7  305  29 15   8.3   4.6 | -28.5 -19.3  295  30 15   8.3   4.6
 24000 -26.3 -15.3  300  28 15   7.6   4.2 | -26.0 -14.8  295  29 15   7.6   4.1
 23000 -24.0 -11.2  300  28 15   7.6   4.2 | -23.8 -10.8  295  30 15   7.6   4.2
 22000 -21.7  -7.1  295  28 15   7.6   4.2 | -21.5  -6.7  295  30 16   7.6   4.2
 21000 -19.6  -3.3  295  28 15   6.7   3.6 | -19.3  -2.7  295  31 16   7.1   3.9
 20000 -17.5   0.5  295  28 14   6.7   3.7 | -17.2   1.0  295  31 16   7.1   3.9
 19500 -16.5   2.3  300  27 14   6.7   3.7 | -16.1   3.0  295  32 16   7.1   3.9
 19000 -15.5   4.1  300  27 14   6.7   3.7 | -15.0   5.0  295  32 17   7.1   3.9
 18500 -14.5   5.9  300  27 14   7.0   3.8 | -14.0   6.8  300  32 17   7.2   3.9
 18000 -13.5   7.7  300  26 14   7.0   3.8 | -12.9   8.8  300  32 17   7.2   3.9
 17500 -12.4   9.7  300  26 13   6.9   3.8 | -11.8  10.8  300  32 17   7.0   3.9
 17000 -11.4  11.5  295  25 13   6.8   3.7 | -10.8  12.6  300  32 16   6.8   3.8
 16500 -10.4  13.3  295  24 12   6.8   3.7 |  -9.8  14.4  295  31 16   6.9   3.8
 16000  -9.6  14.7  295  23 12   5.5   3.0 |  -8.9  16.0  295  30 16   5.5   3.0
 15500  -8.7  16.3  295  22 12   5.7   3.1 |  -8.1  17.4  295  29 15   5.6   3.1
 15000  -7.9  17.8  290  22 11   5.1   2.8 |  -7.3  18.9  295  27 14   6.0   3.3
 14500  -6.8  19.8  285  21 11   5.1   2.8 |  -5.9  21.4  290  25 13   6.0   3.3
 14000  -6.1  21.0  280  20 10   4.7   2.6 |  -5.0  23.0  285  23 12   6.2   3.4
 13500  -5.4  22.3  275  20 10   4.6   2.5 |  -4.1  24.6  280  21 11   6.2   3.4
 13000  -4.6  23.7  270  19 10   5.7   3.1 |  -3.2  26.2  275  21 11   6.5   3.6
 12500  -3.8  25.2  260  19 10   5.4   3.0 |  -2.2  28.0  265  20 11   6.3   3.5
 12000  -2.8  27.0  255  19 10   7.7   4.2 |  -1.2  29.8  260  20 10   8.2   4.5
 11500  -1.7  28.9  250  19 10   7.8   4.3 |   0.0  32.0  255  19 10   8.3   4.6
 11000  -0.6  30.9  250  18  9   8.0   4.4 |   1.2  34.2  250  18  9   7.7   4.2
 10500   0.6  33.1  250  17  9   8.7   4.8 |   2.3  36.1  250  15  8   8.4   4.6
 10250   1.2  34.2  245  16  8   5.1   2.8 |   2.9  37.2  245  14  7   4.7   2.6
 10000   1.4  34.5  245  15  8   4.9   2.7 |   3.1  37.6  245  13  7   4.4   2.4
  9750   2.0  35.6  245  13  7   8.2   4.5 |   3.7  38.7  245  11  6   7.7   4.2
  9500   2.6  36.7  245  12  6   7.5   4.1 |   4.2  39.6  240   9  5   7.4   4.1
  9250   3.1  37.6  245  10  5   6.2   3.4 |   4.7  40.5  235   8  4   5.2   2.8
  9000   3.5  38.3  245   9  4   5.5   3.0 |   5.0  41.0  230   6  3   4.2   2.3
  8750   3.9  39.0  250   7  4   6.0   3.3 |   5.4  41.7  220   5  3   6.0   3.3
  8500   4.4  39.9  250   6  3   6.3   3.5 |   5.8  42.4  210   4  2   5.6   3.1
  8250   4.9  40.8  255   5  2   7.6   4.2 |   6.2  43.2  185   3  1   5.4   3.0
  8000   5.5  41.9  255   4  2   8.6   4.7 |   6.6  43.9  165   3  1   6.0   3.3
  7750   6.1  43.0  255   4  2   8.9   4.9 |   7.1  44.8  155   3  1   6.7   3.7
  7500   6.8  44.2  260   3  2   9.4   5.2 |   7.6  45.7  145   2  1   7.9   4.3
  7250   7.5  45.5  260   3  2  10.0   5.5 |   8.3  46.9  145   2  1   9.8   5.4
  7000   8.3  46.9  260   3  2   9.8   5.4 |   9.0  48.2  150   2  1   9.6   5.3
  6750   9.0  48.2  260   3  2  10.0   5.5 |   9.7  49.5  150   2  1   8.8   4.8
  6500   9.8  49.6  260   3  2  10.8   5.9 |  10.4  50.7  150   2  1  10.0   5.5
  6250  10.6  51.1  260   3  2  11.7   6.4 |  11.2  52.2  155   2  1  11.2   6.1
  6000  11.4  52.5  260   3  2  10.0   5.5 |  12.0  53.6  160   2  1  10.2   5.6
  5750  12.2  54.0  265   3  2  11.7   6.4 |  12.7  54.9  165   2  1   9.6   5.2
  5500  13.2  55.8  265   3  2  15.3   8.4 |  13.4  56.1  165   2  1  10.0   5.5
  5250  14.2  57.6  265   4  2  12.5   6.9 |  14.2  57.6  165   2  1  10.2   5.6
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  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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