Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 291245
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0645 MDT Monday, June 29, 2015

This forecast is for Monday, June 29, 2015:

If the trigger temperature of 88.7 F/31.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1463 ft/min (7.4 m/s)
   Maximum height of thermals.................. 20353 ft MSL (15514 ft AGL)

Forecast maximum temperature................... 100.0 F/38.2 C
Time of trigger temperature.................... 1715 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................. 13154 ft MSL (8315 ft AGL)
Thermal soaring outlook for Tuesday 06/30...... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:51:01 / 20:44:08 MDT
Total possible sunshine........... 14 hr 53 min 7 sec (893 min 7 sec)
Altitude of sun at 13:17:38 MDT... 74.06 degrees

Upper air data from rawinsonde observation taken on 06/29/2015 at 0600 MDT

Freezing level.................. 16846 ft MSL (12007 ft AGL)
Convective condensation level... 17638 ft MSL (12799 ft AGL)
Lifted condensation level....... 18397 ft MSL (13558 ft AGL)
Lifted index.................... -2.1
K index......................... +20.9

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  -66.5 -87.7   055    9    5   7.0   3.9   83.1 181.5    26.3      M    M
 45000  -61.4 -78.5   340   18    9  -5.0  -2.7   66.2 151.1    17.7      M    M
 40000  -54.2 -65.6   005   40   21   5.4   2.9   54.7 130.5    11.3      M    M
 38000  -49.6 -57.3   005   34   17   8.3   4.5   52.8 127.0    10.3      M    M
 36000  -45.0 -49.0   360   27   14   7.8   4.3   51.1 124.0     9.4      M    M
 34000  -40.1 -40.2   360   28   14   7.1   3.9   49.8 121.6     8.7      M    M
 32000  -34.2 -29.6   010   27   14   9.1   5.0   48.9 120.1     8.3      M    M
 30000  -28.9 -20.0   015   27   14   9.2   5.1   48.3 118.9     7.9      M    M
 29000  -26.2 -15.2   020   26   14   9.0   5.0   48.0 118.4     7.8      M    M
 28000  -23.6 -10.5   025   26   13   6.9   3.8   47.5 117.6     7.5      M    M
 27000  -21.3  -6.3   020   25   13   9.2   5.0   46.7 116.1     7.0      M    M
 26000  -19.4  -2.9   020   24   12   6.8   3.7   45.4 113.8     6.0      M    M
 25000  -17.1   1.2   015   23   12   7.6   4.1   44.7 112.4     5.5      M    M
 24000  -15.0   5.0   010   21   11   5.6   3.1   43.7 110.6     4.7      M    M
 23000  -13.3   8.1   360   20   10   5.8   3.2   42.3 108.1     3.5      M    M
 22000  -12.1  10.2   005   20   10   3.6   2.0   40.4 104.6     1.8      M    M
 21000  -10.4  13.3   015   21   11   7.1   3.9   39.0 102.1     0.7      M    M
 20000   -8.5  16.7   350   20   10   6.7   3.7   37.9 100.1    -0.4   1442  7.3
 19500   -7.5  18.5   335   20   10   7.4   4.0   37.4  99.4    -0.9   1399  7.1
 19000   -6.3  20.7   330   19   10   9.4   5.2   37.2  99.0    -1.1   1347  6.8
 18500   -4.9  23.2   330   19   10   9.3   5.1   37.1  98.8    -1.2   1291  6.6
 18000   -3.6  25.5   330   19   10   9.2   5.1   37.0  98.7    -1.3   1235  6.3
 17500   -1.5  29.3   325   20   10   9.2   5.1   37.0  98.5    -1.4   1151  5.8
 17000   -0.1  31.8   325   19   10   9.2   5.1   36.9  98.5    -1.4   1095  5.6
 16500    1.3  34.3   335   17    9   9.2   5.1   36.8  98.3    -1.5   1039  5.3
 16000    2.6  36.7   340   16    8   9.2   5.1   36.7  98.1    -1.6    983  5.0
 15500    4.0  39.2   340   14    7   9.2   5.1   36.6  97.9    -1.8    927  4.7
 15000    5.4  41.7   345   13    7   9.2   5.1   36.5  97.7    -1.9    871  4.4
 14500    6.8  44.2   345   12    6   9.1   5.0   36.4  97.5    -2.0    815  4.1
 14000    8.1  46.6   350   11    5   7.9   4.3   36.3  97.3    -2.1    759  3.9
 13500    9.0  48.2   340    7    4   6.2   3.4   35.7  96.3    -2.7    717  3.6
 13000    9.9  49.8   315    4    2   6.2   3.4   35.1  95.3    -3.2    676  3.4
 12500   10.8  51.4   280   10    5   6.2   3.4   34.6  94.2    -3.8    635  3.2
 12000   11.7  53.1   270   16    8   6.3   3.4   34.0  93.2    -4.4    594  3.0
 11500   12.8  55.0   265   15    7   9.0   4.9   33.7  92.6    -4.8    545  2.8
 11000   14.1  57.4   265   13    7   8.8   4.8   33.5  92.3    -5.0    491  2.5
 10500   15.4  59.7   260   12    6   8.5   4.7   33.4  92.1    -5.2    438  2.2
 10250   16.0  60.8   250   12    6   8.1   4.5   33.2  91.8    -5.3    412  2.1
 10000   16.6  61.9   240   12    6   8.2   4.5   33.1  91.6    -5.4    386  2.0
  9750   17.2  63.0   245   11    6   8.2   4.5   33.0  91.4    -5.5    361  1.8
  9500   17.8  64.0   245   11    6   8.2   4.5   32.9  91.2    -5.7    335  1.7
  9250   18.4  65.1   250   10    5   8.2   4.5   32.8  91.0    -5.8    310  1.6
  9000   19.1  66.4   255   10    5   8.2   4.5   32.7  90.8    -5.9    284  1.4
  8750   19.7  67.5   250    8    4   8.2   4.5   32.5  90.6    -6.1    258  1.3
  8500   20.3  68.5   240    7    4   8.4   4.6   32.4  90.3    -6.2    233  1.2
  8250   20.9  69.6   225    6    3   7.5   4.1   32.3  90.1    -6.4    207  1.1
  8000   21.3  70.3   205    5    3   4.9   2.7   32.0  89.6    -6.6    186  0.9
  7750   21.6  70.9   185    6    3   3.8   2.1   31.6  88.8    -7.1    170  0.9
  7500   21.9  71.4   170    7    3   4.0   2.2   31.1  88.0    -7.6    154  0.8
  7250   22.2  72.0   160    8    4   4.2   2.3   30.7  87.2    -8.0    138  0.7
  7000   22.6  72.7   150   10    5   7.3   4.0   30.4  86.6    -8.4    119  0.6
  6750   23.2  73.8   150   13    7   8.8   4.8   30.3  86.5    -8.5     94  0.5
  6500   23.8  74.8   145   16    8   9.4   5.2   30.2  86.3    -8.7     68  0.3
  6250   24.4  75.9   145   20   10   5.6   3.1   30.1  86.2    -8.8     43  0.2
  6000   24.5  76.1   145   23   12  -2.2  -1.2   29.5  85.0    -9.5     33  0.2
  5750   24.3  75.7   145   22   11  -0.6  -0.3   28.5  83.4   -10.4     32  0.2
  5500   24.4  75.9   140   19   10   4.1   2.2   28.0  82.4   -11.0     19  0.1
  5250   24.8  76.6   135   16    8   5.4   2.9   27.6  81.7   -11.4      1  0.0
  5000   25.2  77.4   125   13    7   2.5   1.4   27.2  81.0   -11.8      M    M

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

           06/29/2015 at 0900 MDT          |       06/29/2015 at 1200 MDT
                                           |
K index... +22.7  LI... +272.8             | K index... +20.1  LI... +271.4
CAPE... +13.5  CIN... -195.6               | CAPE... +266.9  CIN... -87.3
                                           |
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 -65.0 -85.0  020  14  7   2.9   1.6 | -64.2 -83.6  025  12  6   3.2   1.7
 45000 -60.1 -76.2  360  25 13   3.6   2.0 | -59.7 -75.5  010  26 13   2.7   1.5
 40000 -53.6 -64.5  005  38 19   8.1   4.5 | -54.2 -65.6  015  40 21   8.3   4.5
 38000 -48.7 -55.7  010  33 17   8.1   4.4 | -49.3 -56.7  020  34 18   8.2   4.5
 36000 -43.8 -46.8  015  29 15   8.2   4.5 | -44.3 -47.7  025  29 15   8.5   4.6
 34000 -38.9 -38.0  020  26 14   8.3   4.5 | -39.1 -38.4  030  26 14   8.7   4.7
 32000 -33.9 -29.0  030  24 12   8.6   4.7 | -33.3 -27.9  030  23 12   8.8   4.8
 30000 -28.1 -18.6  035  23 12   8.6   4.7 | -28.1 -18.6  035  21 11   8.6   4.7
 29000 -25.6 -14.1  035  23 12   8.5   4.7 | -25.5 -13.9  035  20 10   8.6   4.7
 28000 -23.1  -9.6  035  23 12   7.5   4.1 | -23.0  -9.4  035  19 10   7.8   4.3
 27000 -20.9  -5.6  035  23 12   7.5   4.1 | -20.7  -5.3  040  18 10   7.8   4.3
 26000 -18.6  -1.5  035  23 12   7.5   4.1 | -18.4  -1.1  040  18  9   7.8   4.3
 25000 -16.5   2.3  035  23 12   5.5   3.0 | -16.1   3.0  040  18  9   6.6   3.6
 24000 -15.0   5.0  030  20 11   5.1   2.8 | -14.2   6.4  035  17  9   6.3   3.5
 23000 -13.6   7.5  025  18  9   5.2   2.8 | -12.3   9.9  025  17  9   6.4   3.5
 22000 -12.1  10.2  020  16  8   6.9   3.8 | -10.5  13.1  020  17  9   5.6   3.1
 21000  -9.9  14.2  010  15  8   7.1   3.9 |  -8.9  16.0  010  17  9   5.6   3.1
 20000  -7.8  18.0  355  15  8   7.2   3.9 |  -7.3  18.9  005  18  9   5.8   3.2
 19500  -6.8  19.8  350  15  8   7.5   4.1 |  -6.5  20.3  360  18  9   6.8   3.7
 19000  -5.6  21.9  345  15  8   8.1   4.5 |  -5.4  22.3  360  18  9   8.7   4.8
 18500  -4.5  23.9  345  15  8   8.1   4.5 |  -4.1  24.6  360  18  9   8.8   4.8
 18000  -3.3  26.1  340  15  8   8.6   4.7 |  -2.9  26.8  355  17  9   7.9   4.3
 17500  -2.0  28.4  335  14  7   8.6   4.7 |  -1.7  28.9  355  15  8   7.9   4.3
 17000  -0.7  30.7  335  14  7   8.6   4.7 |  -0.5  31.1  355  13  7   8.1   4.4
 16500   0.6  33.1  335  13  7   8.6   4.7 |   0.7  33.3  350  13  6   8.6   4.7
 16000   1.8  35.2  330  12  6   8.5   4.7 |   2.0  35.6  345  12  6   8.5   4.7
 15500   3.1  37.6  330  11  6   9.3   5.1 |   3.3  37.9  345  12  6   9.2   5.0
 15000   4.5  40.1  330  11  5   9.3   5.1 |   5.4  41.7  345  11  6   9.1   5.0
 14500   6.4  43.5  325  10  5   8.1   4.4 |   6.7  44.1  340  11  5   9.0   4.9
 14000   7.6  45.7  320   9  5   8.2   4.5 |   8.0  46.4  340  10  5   9.0   5.0
 13500   8.8  47.8  310   9  5   8.0   4.4 |   9.3  48.7  335   9  5   8.4   4.6
 13000  10.0  50.0  305  10  5   8.0   4.4 |  10.6  51.1  330   9  5   8.4   4.6
 12500  11.1  52.0  295  10  5   8.2   4.5 |  11.8  53.2  325   8  4   7.9   4.3
 12000  12.4  54.3  290  11  6   8.2   4.5 |  12.9  55.2  315   8  4   7.8   4.3
 11500  13.6  56.5  285  12  6   8.0   4.4 |  14.1  57.4  305   8  4   7.8   4.3
 11000  14.7  58.5  280  12  6   8.1   4.4 |  15.2  59.4  300   8  4   8.0   4.4
 10500  15.8  60.4  280  13  7   5.0   2.7 |  16.1  61.0  290   9  4   5.0   2.7
 10250  16.2  61.2  275  13  7   7.2   4.0 |  16.6  61.9  290   9  5   8.0   4.4
 10000  16.9  62.4  275  13  7   9.9   5.4 |  17.3  63.1  285   9  5  10.2   5.6
  9750  17.6  63.7  275  13  7   9.1   5.0 |  18.0  64.4  285  10  5   9.6   5.3
  9500  18.2  64.8  275  13  7   6.6   3.6 |  18.6  65.5  285  10  5   6.9   3.8
  9250  18.6  65.5  270  12  6   5.6   3.1 |  19.0  66.2  280   9  5   6.6   3.6
  9000  19.0  66.2  270  11  6   7.2   3.9 |  19.6  67.3  280   8  4   8.8   4.8
  8750  19.6  67.3  270   9  5   6.8   3.7 |  20.2  68.4  275   8  4   8.1   4.4
  8500  20.0  68.0  265   8  4   5.4   3.0 |  20.8  69.4  270   7  3   6.7   3.7
  8250  20.4  68.7  265   7  3   4.6   2.5 |  21.2  70.2  265   6  3   6.1   3.3
  8000  20.7  69.3  265   5  3   5.3   2.9 |  21.6  70.9  255   4  2   6.7   3.7
  7750  21.1  70.0  255   4  2   5.3   2.9 |  22.1  71.8  245   4  2   7.9   4.4
  7500  21.4  70.5  235   3  2   4.8   2.6 |  22.7  72.9  235   3  2   9.7   5.3
  7250  21.7  71.1  210   4  2   4.8   2.6 |  23.4  74.1  235   3  2  10.2   5.6
  7000  22.1  71.8  190   5  2   4.6   2.5 |  24.2  75.6  235   3  2   9.9   5.4
  6750  22.4  72.3  175   6  3   4.5   2.5 |  24.9  76.8  230   3  2  10.5   5.7
  6500  22.6  72.7  170   6  3   4.5   2.5 |  25.7  78.3  230   3  2  10.9   6.0
  6250  22.9  73.2  165   6  3   4.9   2.7 |  26.5  79.7  230   3  2  11.1   6.1
  6000  23.2  73.8  160   6  3   3.6   1.9 |  27.3  81.1  230   3  2  10.3   5.6
  5750  23.4  74.1  155   6  3   7.0   3.9 |  28.1  82.6  230   3  2  12.6   6.9
  5500  24.2  75.6  155   6  3  11.9   6.5 |  29.2  84.6  235   3  1  15.8   8.7
  5250  24.9  76.8  155   5  3   8.1   4.4 |  30.3  86.5  235   3  1  13.3   7.3
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/29/2015 at 1500 MDT          |       06/29/2015 at 1800 MDT
                                           |
K index... +22.0  LI... +272.5             | K index... +31.2  LI... +271.3
CAPE... +201.0  CIN... -61.8               | CAPE... +715.2  CIN... -10.3
                                           |
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 -64.1 -83.4  035   6  3   3.5   1.9 | -65.2 -85.4  020   7  4   2.7   1.5
 45000 -59.4 -74.9  025  17  9   2.4   1.3 | -60.5 -76.9  015  16  8   3.9   2.1
 40000 -53.8 -64.8  030  35 18   8.2   4.5 | -53.4 -64.1  025  31 16   8.5   4.6
 38000 -48.8 -55.8  035  31 16   8.3   4.5 | -48.3 -54.9  030  26 14   8.4   4.6
 36000 -43.9 -47.0  040  26 14   8.6   4.7 | -43.2 -45.8  030  22 12   8.4   4.6
 34000 -38.7 -37.7  035  23 12   8.6   4.7 | -37.5 -35.5  030  18  9   8.4   4.6
 32000 -33.5 -28.3  035  21 11   8.8   4.8 | -32.5 -26.5  030  14  7   8.4   4.6
 30000 -28.4 -19.1  030  18  9   8.5   4.7 | -27.6 -17.7  025  14  7   8.2   4.5
 29000 -25.9 -14.6  030  17  9   8.5   4.7 | -25.1 -13.2  025  13  7   8.2   4.5
 28000 -23.4 -10.1  030  16  8   8.0   4.4 | -22.7  -8.9  020  13  7   7.8   4.3
 27000 -20.9  -5.6  030  14  7   8.1   4.4 | -20.4  -4.7  020  12  6   7.8   4.3
 26000 -17.9  -0.2  035  13  7   8.1   4.4 | -18.1  -0.6  020  10  5   7.8   4.3
 25000 -15.6   3.9  035  13  7   6.7   3.7 | -15.8   3.6  020   9  5   7.5   4.1
 24000 -13.6   7.5  035  13  7   6.9   3.8 | -13.5   7.7  025  10  5   7.5   4.1
 23000 -11.6  11.1  030  14  7   6.9   3.8 | -11.3  11.7  030  10  5   7.5   4.1
 22000  -9.6  14.7  025  14  7   5.8   3.2 |  -9.1  15.6  030  11  6   6.0   3.3
 21000  -7.9  17.8  015  15  8   6.0   3.3 |  -7.4  18.7  020  13  7   6.0   3.3
 20000  -6.2  20.8  010  16  8   6.1   3.4 |  -5.7  21.7  015  16  8   6.1   3.4
 19500  -5.3  22.5  005  17  9   6.8   3.7 |  -4.9  23.2  010  18  9   6.5   3.6
 19000  -4.3  24.3  360  17  9   7.4   4.1 |  -3.9  25.0  010  18  9   7.2   3.9
 18500  -3.3  26.1  360  18  9   7.6   4.2 |  -3.0  26.6  005  18  9   7.2   4.0
 18000  -2.2  28.0  355  18  9   8.1   4.4 |  -1.9  28.6  005  18  9   8.1   4.4
 17500  -1.1  30.0  355  17  9   8.1   4.4 |  -0.8  30.6  005  18  9   8.2   4.5
 17000   0.1  32.2  355  17  9   8.2   4.5 |   0.4  32.7  005  17  9   8.2   4.5
 16500   1.4  34.5  360  15  8   8.5   4.6 |   1.5  34.7  005  16  8   8.1   4.4
 16000   2.6  36.7  360  13  7   8.5   4.7 |   2.7  36.9  010  15  8   8.0   4.4
 15500   3.9  39.0  360  12  6   9.1   5.0 |   4.6  40.3  010  14  7   9.5   5.2
 15000   5.3  41.5  360  11  6   9.0   5.0 |   6.0  42.8  010  13  7   9.5   5.2
 14500   6.6  43.9  360  10  5   9.1   5.0 |   7.4  45.3  015  13  6   9.6   5.3
 14000   8.0  46.4  360   9  5   9.1   5.0 |   8.8  47.8  015  12  6   9.6   5.3
 13500   9.3  48.7  360   9  5   9.0   4.9 |  10.2  50.4  015  11  6   9.5   5.2
 13000  11.3  52.3  360   8  4   8.8   4.8 |  11.7  53.1  015  11  6   9.5   5.2
 12500  12.6  54.7  360   8  4   8.9   4.9 |  13.1  55.6  020  10  5   9.2   5.0
 12000  14.0  57.2  360   7  4   8.9   4.9 |  14.4  57.9  020   9  5   9.1   5.0
 11500  15.3  59.5  360   7  3   9.3   5.1 |  15.8  60.4  025   8  4   8.9   4.9
 11000  16.7  62.1  360   6  3  10.2   5.6 |  17.1  62.8  025   7  4   9.0   4.9
 10500  17.6  63.7  355   5  3   5.3   2.9 |  18.3  64.9  035   6  3   5.5   3.0
 10250  18.3  64.9  350   5  2  10.8   5.9 |  18.7  65.7  035   6  3   7.8   4.3
 10000  19.1  66.4  350   4  2  10.6   5.8 |  19.5  67.1  040   5  3  10.4   5.7
  9750  19.9  67.8  345   4  2  10.4   5.7 |  20.2  68.4  045   5  3  10.2   5.6
  9500  20.5  68.9  340   3  2   7.3   4.0 |  20.9  69.6  050   5  2   8.2   4.5
  9250  21.0  69.8  330   3  2   7.1   3.9 |  21.5  70.7  055   4  2   7.4   4.1
  9000  21.6  70.9  325   3  2   9.1   5.0 |  22.1  71.8  055   4  2   9.0   4.9
  8750  22.2  72.0  320   3  1   8.6   4.7 |  22.8  73.0  060   3  2   8.5   4.7
  8500  22.9  73.2  310   3  1   8.6   4.7 |  23.5  74.3  070   3  2   8.9   4.9
  8250  23.4  74.1  310   3  1   8.6   4.7 |  24.1  75.4  070   3  1   8.9   4.9
  8000  24.0  75.2  310   3  1   8.7   4.8 |  24.8  76.6  075   3  1   8.4   4.6
  7750  24.6  76.3  305   2  1   9.2   5.0 |  25.4  77.7  080   2  1   8.3   4.6
  7500  25.3  77.5  300   2  1  10.0   5.5 |  26.1  79.0  085   2  1   9.3   5.1
  7250  26.1  79.0  300   2  1  10.4   5.7 |  26.8  80.2  085   2  1   9.9   5.4
  7000  26.9  80.4  295   2  1  10.0   5.5 |  27.6  81.7  085   2  1   9.6   5.3
  6750  27.6  81.7  295   2  1  10.3   5.7 |  28.3  82.9  090   2  1  10.0   5.5
  6500  28.4  83.1  290   2  1  10.9   6.0 |  29.0  84.2  095   2  1  10.7   5.9
  6250  29.2  84.6  290   2  1  11.2   6.2 |  29.8  85.6  095   2  1  11.3   6.2
  6000  30.0  86.0  285   2  1   9.9   5.5 |  30.7  87.3  100   2  1   9.8   5.4
  5750  30.8  87.4  285   2  1  12.6   6.9 |  31.4  88.5  105   2  1   9.7   5.3
  5500  31.9  89.4  285   2  1  16.5   9.1 |  32.2  90.0  100   2  1  11.5   6.3
  5250  33.0  91.4  290   2  1  13.4   7.4 |  33.0  91.4  090   2  1  10.5   5.7
  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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