Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 061304
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0704 MDT Wednesday, May 6, 2015

This forecast is for Wednesday, May 6, 2015:

If the trigger temperature of 59.9 F/15.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 233 ft/min (1.2 m/s)
   Maximum height of thermals.................. 10930 ft MSL (6091 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 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................. 8644 ft MSL (3805 ft AGL)
Thermal soaring outlook for Thursday 05/07..... Fair

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

Remarks...

Sunrise/Sunset.................... 06:10:27 / 20:10:53 MDT
Total possible sunshine........... 14 hr 0 min 26 sec (840 min 26 sec)
Altitude of sun at 13:10:50 MDT... 67.48 degrees

Upper air data from rawinsonde observation taken on 05/06/2015 at 0600 MDT

Freezing level.................. 10968 ft MSL (6129 ft AGL)
Convective condensation level... 8609 ft MSL (3770 ft AGL)
Lifted condensation level....... 9909 ft MSL (5069 ft AGL)
Lifted index.................... -1.3
K index......................... +26.6

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  -56.4 -69.5   220   26   13  -3.0  -1.7  105.6 222.0    49.9      M    M
 45000  -54.0 -65.2   225   22   11   2.5   1.4   85.0 184.9    40.8      M    M
 40000  -59.4 -74.9   225   26   13  -6.7  -3.7   53.4 128.1    23.0      M    M
 38000  -59.0 -74.2   215   18    9   6.9   3.8   45.1 113.2    18.0      M    M
 36000  -57.6 -71.7   175   16    8  -2.4  -1.3   38.6 101.5    14.0      M    M
 34000  -52.0 -61.6   155   18    9   9.5   5.2   37.2  99.0    13.5      M    M
 32000  -46.6 -51.9   160   17    9   9.0   4.9   36.7  98.0    13.4      M    M
 30000  -41.3 -42.3   175   15    8   8.1   4.5   35.9  96.6    13.2      M    M
 29000  -38.8 -37.8   185   10    5   9.6   5.3   35.4  95.7    12.9      M    M
 28000  -36.2 -33.2   210    6    3   8.0   4.4   35.0  95.1    12.8      M    M
 27000  -33.8 -28.8   220    7    4   7.9   4.4   34.2  93.6    12.4      M    M
 26000  -31.4 -24.5   225    9    4   8.0   4.4   33.6  92.5    12.0      M    M
 25000  -29.3 -20.7   230   10    5   6.6   3.6   32.6  90.8    11.4      M    M
 24000  -26.2 -15.2   265   11    6   8.6   4.7   32.9  91.2    11.6      M    M
 23000  -23.8 -10.8   250   11    6   8.1   4.4   32.3  90.1    11.2      M    M
 22000  -21.5  -6.7   260   11    6   7.5   4.1   31.6  88.9    10.8      M    M
 21000  -19.4  -2.9   265   11    6   7.0   3.8   30.6  87.0    10.0      M    M
 20000  -17.3   0.9   275   11    6   7.0   3.9   29.6  85.4     9.3      M    M
 19500  -16.3   2.7   270   11    6   7.0   3.9   29.1  84.4     8.9      M    M
 19000  -15.2   4.6   265   12    6   7.0   3.9   28.6  83.5     8.5      M    M
 18500  -13.7   7.3   260   13    7   6.2   3.4   27.9  82.1     7.9      M    M
 18000  -12.8   9.0   260   13    6   6.2   3.4   27.2  81.0     7.4      M    M
 17500  -11.9  10.6   255   12    6   6.2   3.4   26.6  80.0     6.9      M    M
 17000  -11.0  12.2   255   12    6   6.2   3.4   26.1  78.9     6.4      M    M
 16500  -10.1  13.8   255   12    6   6.2   3.4   25.4  77.8     5.9      M    M
 16000   -9.2  15.4   255   12    6   6.2   3.4   24.9  76.7     5.3      M    M
 15500   -8.3  17.1   260   13    7   7.2   3.9   24.3  75.7     4.8      M    M
 15000   -7.2  19.0   265   14    7   7.5   4.1   23.9  75.0     4.5      M    M
 14500   -6.1  21.0   265   15    8   7.5   4.1   23.5  74.4     4.1      M    M
 14000   -5.0  23.0   270   16    8   7.4   4.0   23.2  73.7     3.8      M    M
 13500   -4.0  24.8   275   15    8   6.5   3.6   22.8  73.0     3.4      M    M
 13000   -3.2  26.2   275   14    7   5.4   3.0   22.1  71.7     2.7      M    M
 12500   -2.4  27.7   280   13    7   5.4   3.0   21.4  70.4     2.0      M    M
 12000   -1.7  28.9   285   12    6   5.4   3.0   20.7  69.2     1.4      M    M
 11500   -0.9  30.4   285   11    6   5.7   3.1   20.0  68.0     0.7      M    M
 11000   -0.0  32.0   280   11    6   5.8   3.2   19.4  66.9     0.1      M    M
 10500    0.8  33.4   275   10    5   5.8   3.2   18.7  65.7    -0.6    398  2.0
 10250    1.2  34.2   270   10    5   5.8   3.2   18.4  65.2    -0.9    378  1.9
 10000    1.6  34.9   265   10    5   5.8   3.2   18.1  64.6    -1.2    358  1.8
  9750    2.0  35.6   275   16    8   5.7   3.1   17.8  64.0    -1.5    338  1.7
  9500    2.4  36.3   270   19   10   5.6   3.1   17.5  63.4    -1.8    319  1.6
  9250    2.8  37.0   270   21   11   5.7   3.1   17.1  62.9    -2.2    299  1.5
  9000    3.3  37.9   270   24   12   5.7   3.1   16.8  62.3    -2.5    280  1.4
  8750    3.7  38.7   270   23   12   5.6   3.1   16.5  61.7    -2.8    260  1.3
  8500    4.1  39.4   265   22   11   5.7   3.1   16.2  61.1    -3.2    241  1.2
  8250    4.5  40.1   265   21   11   5.5   3.0   15.9  60.5    -3.5    221  1.1
  8000    4.9  40.8   260   20   10   6.1   3.3   15.5  60.0    -3.8    202  1.0
  7750    5.3  41.5   260   19   10   7.0   3.8   15.3  59.6    -4.1    180  0.9
  7500    5.9  42.6   255   17    9   7.1   3.9   15.1  59.2    -4.3    158  0.8
  7250    6.4  43.5   255   15    8   7.1   3.9   14.9  58.8    -4.5    135  0.7
  7000    6.9  44.4   250   13    7   7.1   3.9   14.7  58.5    -4.8    112  0.6
  6750    7.4  45.3   250   11    6   7.1   3.9   14.5  58.1    -5.0     90  0.5
  6500    7.9  46.2   255    8    4   7.1   3.9   14.3  57.7    -5.3     67  0.3
  6250    8.4  47.1   265    6    3   7.1   3.9   14.1  57.4    -5.5     45  0.2
  6000    8.9  48.0   280    4    2   7.1   3.9   13.9  57.0    -5.7     22  0.1
  5750    9.4  48.9   290    3    1   7.1   3.9   13.7  56.7    -6.0      M    M
  5500    9.9  49.8   290    2    1   7.2   3.9   13.5  56.3    -6.2      M    M
  5250   10.4  50.7   290    1    1   6.9   3.8   13.3  55.9    -6.5      M    M
  5000   10.9  51.6   290    1    0   7.9   4.4   13.1  55.6    -6.7      M    M

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

           05/06/2015 at 0900 MDT          |       05/06/2015 at 1200 MDT
                                           |
K index... +25.1  LI... +273.1             | K index... +24.7  LI... +272.7
CAPE... +72.7  CIN... -1.8                 | CAPE... +81.2  CIN... -0.4
                                           |
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 -55.4 -67.7  220  28 14   2.4   1.3 | -55.3 -67.5  215  27 14   2.3   1.3
 45000 -52.1 -61.8  220  28 14  -2.3  -1.3 | -52.0 -61.6  215  29 15  -2.2  -1.2
 40000 -58.0 -72.4  215  24 12  -3.8  -2.1 | -58.1 -72.6  210  25 13  -3.9  -2.2
 38000 -57.6 -71.7  200  22 11   3.6   2.0 | -57.5 -71.5  200  24 12   4.2   2.3
 36000 -55.4 -67.7  170  23 12   3.6   2.0 | -54.9 -66.8  180  26 13   4.2   2.3
 34000 -52.4 -62.3  155  26 14   8.8   4.8 | -51.8 -61.2  170  29 15   8.2   4.5
 32000 -47.1 -52.8  160  25 13   8.9   4.9 | -46.8 -52.2  175  30 15   8.4   4.6
 30000 -41.7 -43.1  165  22 11   9.1   5.0 | -41.8 -43.2  175  28 14   8.3   4.5
 29000 -39.0 -38.2  170  20 11   9.1   5.0 | -39.3 -38.7  180  24 12   8.3   4.6
 28000 -36.3 -33.3  175  19 10   9.1   5.0 | -36.8 -34.2  190  20 10   8.3   4.6
 27000 -33.6 -28.5  180  17  9   8.8   4.8 | -33.7 -28.7  200  16  8   8.6   4.7
 26000 -30.5 -22.9  190  14  7   8.3   4.6 | -31.1 -24.0  210  14  7   8.6   4.7
 25000 -28.0 -18.4  205  11  6   8.3   4.6 | -28.6 -19.5  225  13  7   8.6   4.7
 24000 -25.5 -13.9  220  10  5   7.8   4.3 | -26.0 -14.8  235  12  6   7.9   4.3
 23000 -23.3  -9.9  235   9  5   7.5   4.1 | -23.8 -10.8  245  12  6   7.3   4.0
 22000 -21.1  -6.0  245   9  5   7.5   4.1 | -21.7  -7.1  255  13  6   7.3   4.0
 21000 -19.0  -2.2  260  10  5   6.8   3.7 | -19.5  -3.1  265  13  7   7.2   4.0
 20000 -17.0   1.4  265  12  6   6.7   3.7 | -17.4   0.7  270  14  7   7.2   4.0
 19500 -16.0   3.2  270  14  7   6.7   3.7 | -16.3   2.7  270  14  7   7.2   4.0
 19000 -15.1   4.8  275  15  8   6.7   3.7 | -15.3   4.5  270  15  8   7.2   4.0
 18500 -14.1   6.6  275  16  8   6.8   3.7 | -14.2   6.4  270  15  8   6.9   3.8
 18000 -13.1   8.4  275  18  9   6.9   3.8 | -13.2   8.2  270  16  8   6.6   3.6
 17500 -12.1  10.2  275  20 10   7.0   3.9 | -12.3   9.9  275  17  9   6.6   3.6
 17000 -11.2  11.8  275  21 11   5.4   3.0 | -11.3  11.7  275  18  9   6.6   3.6
 16500 -10.4  13.3  275  22 11   5.6   3.1 | -10.4  13.3  275  19 10   6.6   3.6
 16000  -9.5  14.9  270  22 11   5.9   3.2 |  -9.5  14.9  275  20 10   6.5   3.6
 15500  -8.7  16.3  270  22 12   6.0   3.3 |  -8.5  16.7  275  19 10   6.4   3.5
 15000  -7.8  18.0  270  22 12   6.3   3.4 |  -7.6  18.3  275  19 10   6.2   3.4
 14500  -6.9  19.6  270  22 11   6.9   3.8 |  -6.8  19.8  275  18  9   5.7   3.1
 14000  -5.9  21.4  270  21 11   6.8   3.8 |  -5.9  21.4  275  17  9   5.7   3.1
 13500  -5.0  23.0  270  20 10   5.3   2.9 |  -5.1  22.8  275  14  7   5.4   3.0
 13000  -3.8  25.2  275  18  9   5.5   3.0 |  -3.9  25.0  280   9  5   5.5   3.0
 12500  -3.0  26.6  280  17  9   5.6   3.1 |  -3.1  26.4  295   7  4   5.6   3.1
 12000  -2.2  28.0  285  15  8   5.7   3.1 |  -2.3  27.9  320   5  3   5.7   3.1
 11500  -1.4  29.5  285  16  8   5.9   3.2 |  -1.4  29.5  335   6  3   5.9   3.2
 11000  -0.6  30.9  290  16  8   5.5   3.0 |  -0.6  30.9  345   7  4   6.1   3.3
 10500   0.2  32.4  290  16  8   4.4   2.4 |   0.4  32.7  340   7  4   6.2   3.4
 10250   0.5  32.9  290  17  8   6.2   3.4 |   0.8  33.4  335   7  4   7.1   3.9
 10000   1.0  33.8  290  16  8   7.3   4.0 |   1.4  34.5  335   8  4   7.7   4.2
  9750   1.5  34.7  290  16  8   6.0   3.3 |   1.9  35.4  330   8  4   7.1   3.9
  9500   1.9  35.4  290  16  8   6.4   3.5 |   2.4  36.3  320   8  4   7.3   4.0
  9250   2.4  36.3  290  16  8   5.6   3.1 |   2.9  37.2  315   8  4   6.9   3.8
  9000   2.8  37.0  290  15  8   6.4   3.5 |   3.4  38.1  310   8  4   6.5   3.6
  8750   3.3  37.9  285  16  8   7.9   4.3 |   3.9  39.0  305   8  4   6.8   3.7
  8500   3.9  39.0  285  16  8   7.2   4.0 |   4.3  39.7  295   9  5   6.5   3.6
  8250   4.4  39.9  285  17  9   8.6   4.7 |   4.8  40.6  290  10  5   7.6   4.2
  8000   5.0  41.0  280  18  9   8.5   4.7 |   5.3  41.5  285  10  5   9.2   5.0
  7750   5.6  42.1  280  19 10   6.6   3.6 |   6.0  42.8  285  10  5   9.1   5.0
  7500   6.0  42.8  275  20 10   6.4   3.5 |   6.6  43.9  285  11  5   8.8   4.8
  7250   6.5  43.7  275  20 11   6.9   3.8 |   7.3  45.1  285  11  6   9.6   5.2
  7000   7.0  44.6  270  20 10   7.1   3.9 |   8.0  46.4  280  11  6  10.5   5.7
  6750   7.5  45.5  270  18  9   6.3   3.5 |   8.8  47.8  280  11  6  10.3   5.6
  6500   7.9  46.2  270  15  8   6.3   3.5 |   9.6  49.3  280  11  6  10.3   5.7
  6250   8.4  47.1  270  13  7   8.1   4.4 |  10.3  50.5  280  11  6  10.9   6.0
  6000   9.0  48.2  270  12  6   9.1   5.0 |  11.2  52.2  280  11  5  11.6   6.3
  5750   9.7  49.5  270  10  5   9.8   5.4 |  12.0  53.6  280  10  5  10.9   6.0
  5500  10.4  50.7  270   8  4   8.2   4.5 |  12.9  55.2  280  10  5  13.4   7.4
  5250  10.8  51.4  270   8  4   3.0   1.7 |  14.0  57.2  280  10  5  19.4  10.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/06/2015 at 1500 MDT          |       05/06/2015 at 1800 MDT
                                           |
K index... +24.7  LI... +273.1             | K index... +25.9  LI... +271.6
CAPE... +38.2  CIN... -19.2                | CAPE... +218.3  CIN... -49.7
                                           |
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 -55.5 -67.9  215  28 15   2.3   1.3 | -55.8 -68.4  215  28 14   2.2   1.2
 45000 -52.1 -61.8  215  32 16  -1.5  -0.8 | -52.6 -62.7  220  30 15  -1.7  -0.9
 40000 -56.6 -69.9  200  26 13  -2.9  -1.6 | -57.5 -71.5  195  28 14  -3.2  -1.7
 38000 -56.4 -69.5  190  25 13   2.4   1.3 | -57.1 -70.8  185  28 14   3.2   1.8
 36000 -54.9 -66.8  185  25 13   2.4   1.3 | -55.1 -67.2  170  29 15   3.2   1.8
 34000 -52.5 -62.5  175  25 13   8.8   4.8 | -52.4 -62.3  160  30 16   8.4   4.6
 32000 -47.1 -52.8  185  21 11   9.1   5.0 | -47.3 -53.1  160  26 14   8.6   4.7
 30000 -41.7 -43.1  195  17  9   8.6   4.7 | -42.1 -43.8  160  23 12   8.9   4.9
 29000 -39.1 -38.4  200  15  8   8.6   4.7 | -39.5 -39.1  165  22 12   8.9   4.9
 28000 -36.5 -33.7  210  13  7   8.7   4.7 | -36.8 -34.2  170  22 11   8.9   4.9
 27000 -33.3 -27.9  225  12  6   8.1   4.5 | -34.2 -29.6  175  21 11   8.6   4.7
 26000 -30.9 -23.6  235  12  6   8.1   4.5 | -31.2 -24.2  185  20 10   8.2   4.5
 25000 -28.5 -19.3  245  12  6   8.2   4.5 | -28.7 -19.7  195  19 10   8.2   4.5
 24000 -26.1 -15.0  250  12  6   7.7   4.2 | -26.3 -15.3  205  19 10   7.8   4.3
 23000 -23.9 -11.0  255  12  6   7.4   4.1 | -24.1 -11.4  210  19 10   7.5   4.1
 22000 -21.7  -7.1  260  13  7   7.4   4.1 | -21.8  -7.2  215  19 10   7.5   4.1
 21000 -19.5  -3.1  260  13  7   7.2   4.0 | -19.6  -3.3  220  19 10   6.9   3.8
 20000 -17.4   0.7  260  15  8   7.2   4.0 | -17.6   0.3  230  21 11   6.8   3.8
 19500 -16.3   2.7  260  16  8   7.2   4.0 | -16.6   2.1  235  22 11   6.8   3.8
 19000 -15.3   4.5  265  16  8   7.2   4.0 | -15.5   4.1  235  23 12   6.8   3.7
 18500 -14.2   6.4  265  17  9   6.7   3.7 | -14.5   5.9  240  24 12   6.5   3.6
 18000 -13.3   8.1  260  19 10   6.3   3.5 | -13.6   7.5  240  27 14   6.2   3.4
 17500 -12.4   9.7  260  20 10   6.3   3.5 | -12.7   9.1  245  29 15   6.2   3.4
 17000 -11.5  11.3  260  22 11   5.9   3.2 | -11.7  10.9  245  31 16   6.7   3.7
 16500 -10.6  12.9  260  24 12   5.9   3.3 | -10.8  12.6  245  32 17   6.7   3.7
 16000  -9.8  14.4  260  26 13   5.9   3.2 |  -9.8  14.4  245  33 17   7.1   3.9
 15500  -8.9  16.0  260  27 14   5.9   3.2 |  -8.8  16.2  245  33 17   7.3   4.0
 15000  -8.1  17.4  255  29 15   6.1   3.3 |  -7.7  18.1  240  33 17   7.7   4.2
 14500  -7.1  19.2  255  30 15   6.4   3.5 |  -6.5  20.3  240  32 17   8.6   4.7
 14000  -6.2  20.8  255  30 16   6.4   3.5 |  -5.3  22.5  240  31 16   8.6   4.7
 13500  -4.7  23.5  255  30 15   6.7   3.7 |  -4.1  24.6  240  30 15   8.2   4.5
 13000  -3.8  25.2  250  29 15   6.9   3.8 |  -2.4  27.7  235  27 14   8.0   4.4
 12500  -2.7  27.1  250  28 14   7.1   3.9 |  -1.2  29.8  235  25 13   7.7   4.2
 12000  -1.7  28.9  250  26 14   7.1   3.9 |  -0.1  31.8  235  24 12   7.9   4.3
 11500  -0.7  30.7  245  24 13   7.0   3.8 |   1.0  33.8  235  22 11   8.2   4.5
 11000   0.3  32.5  245  22 12   6.6   3.6 |   2.2  36.0  230  19 10   7.8   4.3
 10500   1.2  34.2  245  19 10   5.8   3.2 |   3.3  37.9  230  17  9   7.1   3.9
 10250   1.7  35.1  245  18  9   7.4   4.1 |   3.8  38.8  225  16  8   8.1   4.4
 10000   2.3  36.1  245  16  8   8.3   4.5 |   4.4  39.9  225  15  8   8.2   4.5
  9750   2.8  37.0  240  15  8   7.2   4.0 |   4.9  40.8  220  14  7   7.3   4.0
  9500   3.3  37.9  240  14  7   7.2   4.0 |   5.5  41.9  215  13  7   7.3   4.0
  9250   3.9  39.0  240  12  6   8.0   4.4 |   6.0  42.8  210  12  6   7.4   4.1
  9000   4.5  40.1  235  12  6   7.6   4.2 |   6.5  43.7  210  11  6   6.8   3.7
  8750   5.0  41.0  235  11  6   6.6   3.6 |   7.0  44.6  205  11  5   6.3   3.5
  8500   5.4  41.7  230  10  5   6.7   3.7 |   7.4  45.3  195  10  5   6.1   3.4
  8250   5.9  42.6  225   9  5   7.5   4.1 |   7.9  46.2  190  10  5   7.4   4.1
  8000   6.5  43.7  225   8  4   7.6   4.2 |   8.5  47.3  180   9  5   6.7   3.6
  7750   7.0  44.6  220   8  4   6.7   3.7 |   8.8  47.8  175   9  5   4.8   2.6
  7500   7.5  45.5  215   8  4   6.4   3.5 |   9.2  48.6  165   8  4   5.0   2.8
  7250   8.0  46.4  205   7  4   7.8   4.3 |   9.6  49.3  160   8  4   5.9   3.2
  7000   8.6  47.5  205   7  4   9.0   4.9 |  10.1  50.2  155   8  4   8.0   4.4
  6750   9.2  48.6  200   7  4   7.8   4.3 |  10.7  51.3  155   8  4   8.7   4.8
  6500   9.7  49.5  200   7  4   7.8   4.3 |  11.3  52.3  150   7  4   8.4   4.6
  6250  10.3  50.5  200   7  4   9.7   5.3 |  12.0  53.6  150   7  4  10.0   5.5
  6000  11.1  52.0  195   7  4  10.8   5.9 |  12.8  55.0  150   7  3  10.9   6.0
  5750  11.9  53.4  195   7  4  10.4   5.7 |  13.5  56.3  150   6  3   9.2   5.1
  5500  12.6  54.7  195   7  3  10.5   5.8 |  14.2  57.6  150   6  3   8.9   4.9
  5250  13.4  56.1  200   7  3  10.5   5.8 |  14.8  58.6  150   6  3   9.7   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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