Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 291412
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0812 MDT Wednesday, July 29, 2015

This forecast is for Wednesday, July 29, 2015:

If the trigger temperature of 80.8 F/27.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1033 ft/min (5.2 m/s)
   Maximum height of thermals.................. 17710 ft MSL (12871 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1130 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................. 12305 ft MSL (7465 ft AGL)
Thermal soaring outlook for Thursday 07/30..... Good

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

Remarks...

Sunrise/Sunset.................... 06:11:50 / 20:29:39 MDT
Total possible sunshine........... 14 hr 17 min 49 sec (857 min 49 sec)
Altitude of sun at 13:20:32 MDT... 69.54 degrees

Upper air data from rawinsonde observation taken on 07/29/2015 at 0600 MDT

Freezing level.................. 15543 ft MSL (10704 ft AGL)
Convective condensation level... 21102 ft MSL (16263 ft AGL)
Lifted condensation level....... 19978 ft MSL (15139 ft AGL)
Lifted index.................... +1.9
K index......................... +9.9

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  -67.3 -89.1   250   39   20   4.4   2.4   81.9 179.5    27.8      M    M
 45000  -59.7 -75.5   230   48   25   6.5   3.6   70.3 158.5    22.6      M    M
 40000  -52.5 -62.5   235   75   38   8.2   4.5   57.7 135.8    15.9      M    M
 38000  -47.6 -53.7   230   72   37   8.2   4.5   56.5 133.7    15.5      M    M
 36000  -42.8 -45.0   235   64   33   5.8   3.2   54.9 130.9    14.8      M    M
 34000  -38.7 -37.7   235   56   29   6.9   3.8   52.1 125.8    13.1      M    M
 32000  -34.6 -30.3   235   49   25   7.7   4.2   50.0 122.0    11.9      M    M
 30000  -29.3 -20.7   235   44   23   7.6   4.2   48.3 118.9    10.9      M    M
 29000  -27.1 -16.8   240   40   21   7.7   4.2   47.4 117.3    10.4      M    M
 28000  -24.9 -12.8   245   36   18   5.4   3.0   46.4 115.5     9.7      M    M
 27000  -23.2  -9.8   250   32   17   5.6   3.1   44.8 112.6     8.5      M    M
 26000  -21.6  -6.9   260   29   15   5.3   2.9   43.3 109.9     7.4      M    M
 25000  -20.4  -4.7   260   27   14   7.8   4.3   41.1 106.0     5.8      M    M
 24000  -18.1  -0.6   255   25   13   7.8   4.3   40.3 104.6     5.2      M    M
 23000  -15.7   3.7   250   23   12   8.1   4.4   39.6 103.4     4.7      M    M
 22000  -14.1   6.6   255   19   10   9.2   5.1   38.1 100.6     3.5      M    M
 21000  -11.6  11.1   260   19   10   8.5   4.7   37.7  99.8     3.1      M    M
 20000   -9.0  15.8   255   18    9   8.6   4.7   37.2  99.0     2.7      M    M
 19500   -7.9  17.8   250   17    9   6.8   3.7   36.9  98.4     2.5      M    M
 19000   -7.0  19.4   245   15    8   5.8   3.2   36.2  97.2     1.9      M    M
 18500   -6.1  21.0   235   13    7   5.8   3.2   35.5  96.0     1.3      M    M
 18000   -5.3  22.5   225   12    6   5.9   3.3   34.9  94.8     0.7      M    M
 17500   -4.8  23.4   225   12    6   1.7   0.9   33.8  92.9    -0.3   1129  5.7
 17000   -4.0  24.8   225   11    6   9.0   5.0   33.2  91.7    -0.9   1090  5.5
 16500   -2.1  28.2   230   10    5   8.5   4.7   32.9  91.1    -1.2   1012  5.1
 16000   -0.9  30.4   235   10    5   8.5   4.7   32.7  90.8    -1.5    960  4.9
 15500    0.4  32.7   235   10    5   8.5   4.7   32.4  90.4    -1.7    908  4.6
 15000    1.6  34.9   240   11    5   8.6   4.7   32.2  90.0    -1.9    856  4.4
 14500    2.9  37.2   240   11    6   8.5   4.7   32.1  89.7    -2.1    804  4.1
 14000    4.1  39.4   240   11    6   8.5   4.7   31.9  89.4    -2.3    751  3.8
 13500    5.4  41.7   250   10    5   8.5   4.7   31.6  88.9    -2.5    698  3.5
 13000    6.7  44.1   260    9    4   8.5   4.7   31.4  88.6    -2.8    645  3.3
 12500    7.9  46.2   275    8    4   8.5   4.7   31.2  88.2    -2.9    593  3.0
 12000    9.2  48.6   285    8    4   7.7   4.2   31.1  87.9    -3.1    540  2.7
 11500   10.1  50.2   310    6    3   5.7   3.2   30.5  86.9    -3.7    498  2.5
 11000   11.0  51.8   345    5    3   5.7   3.2   29.9  85.8    -4.3    458  2.3
 10500   11.8  53.2   015    7    4   5.1   2.8   29.3  84.7    -5.0    418  2.1
 10250   12.1  53.8   015    7    4   4.3   2.3   28.8  83.9    -5.4    400  2.0
 10000   12.5  54.5   015    7    4   6.6   3.6   28.5  83.3    -5.7    381  1.9
  9750   13.1  55.6   015    7    4   8.0   4.4   28.3  83.0    -5.9    356  1.8
  9500   13.7  56.7   015    8    4   7.6   4.2   28.2  82.7    -6.0    332  1.7
  9250   14.3  57.7   015    8    4   7.7   4.2   28.0  82.4    -6.2    307  1.6
  9000   14.8  58.6   015    8    4   7.7   4.2   27.9  82.2    -6.4    283  1.4
  8750   15.4  59.7   015    7    4   7.7   4.2   27.7  81.9    -6.5    258  1.3
  8500   16.0  60.8   020    6    3   7.7   4.2   27.5  81.6    -6.7    234  1.2
  8250   16.5  61.7   025    5    3   7.7   4.2   27.4  81.3    -6.9    209  1.1
  8000   17.1  62.8   030    4    2   7.7   4.2   27.2  81.0    -7.0    184  0.9
  7750   17.7  63.9   030    4    2   7.7   4.2   27.1  80.7    -7.2    160  0.8
  7500   18.3  64.9   035    4    2   7.6   4.2   26.9  80.4    -7.4    135  0.7
  7250   18.8  65.8   035    3    2   8.0   4.4   26.7  80.1    -7.6    111  0.6
  7000   19.4  66.9   040    3    2   6.3   3.5   26.6  79.8    -7.8     86  0.4
  6750   19.8  67.6   040    2    1   4.6   2.5   26.2  79.2    -8.2     68  0.3
  6500   20.1  68.2   050    1    0   5.1   2.8   25.8  78.5    -8.5     50  0.3
  6250   20.5  68.9   000    0    0   5.0   2.7   25.5  77.9    -8.9     32  0.2
  6000   20.9  69.6   210    2    1   5.0   2.7   25.1  77.2    -9.3     13  0.1
  5750   21.2  70.2   155    1    1   5.1   2.8   24.8  76.6    -9.7      M    M
  5500   21.6  70.9   085    2    1   4.7   2.6   24.4  75.9   -10.1      M    M
  5250   21.9  71.4   075    5    2   6.0   3.3   24.1  75.3   -10.5      M    M
  5000   22.1  71.8   070    7    3  -8.8  -4.8   23.5  74.2   -11.1      M    M

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

           07/29/2015 at 0900 MDT          |       07/29/2015 at 1200 MDT
                                           |
K index... +10.8  LI... +276.8             | K index... +10.4  LI... +276.4
CAPE... 0.0  CIN... -0.2                   | 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 -64.2 -83.6  250  28 14   2.2   1.2 | -64.3 -83.7  240  25 13   2.3   1.3
 45000 -59.6 -75.3  250  48 25   5.0   2.7 | -59.4 -74.9  245  45 23   4.6   2.5
 40000 -51.2 -60.2  250  76 39   7.2   3.9 | -51.8 -61.2  250  71 37   7.8   4.3
 38000 -46.9 -52.4  245  69 36   7.1   3.9 | -47.1 -52.8  245  65 34   7.8   4.3
 36000 -42.6 -44.7  240  62 32   7.3   4.0 | -42.5 -44.5  240  59 31   7.7   4.2
 34000 -38.1 -36.6  240  56 29   7.5   4.1 | -38.2 -36.8  245  52 27   7.2   3.9
 32000 -33.6 -28.5  240  49 25   7.6   4.2 | -33.4 -28.1  245  44 23   7.1   3.9
 30000 -29.5 -21.1  245  42 21   6.7   3.7 | -29.3 -20.7  250  39 20   6.7   3.7
 29000 -27.5 -17.5  250  38 19   6.7   3.7 | -27.3 -17.1  250  37 19   6.7   3.7
 28000 -25.5 -13.9  250  34 18   6.3   3.5 | -25.3 -13.5  250  34 18   6.5   3.5
 27000 -23.7 -10.7  255  31 16   6.2   3.4 | -23.4 -10.1  250  31 16   6.5   3.6
 26000 -21.8  -7.2  255  28 15   6.2   3.4 | -21.5  -6.7  250  28 15   6.5   3.6
 25000 -20.0  -4.0  260  26 13   6.3   3.4 | -19.5  -3.1  250  26 13   6.9   3.8
 24000 -17.9  -0.2  265  23 12   7.0   3.9 | -17.3   0.9  250  23 12   7.3   4.0
 23000 -15.8   3.6  265  21 11   7.0   3.9 | -15.2   4.6  255  21 11   7.3   4.0
 22000 -13.2   8.2  265  19 10   6.2   3.4 | -13.0   8.6  255  19 10   6.8   3.7
 21000 -11.4  11.5  260  17  9   6.2   3.4 | -11.1  12.0  260  17  9   6.4   3.5
 20000  -9.6  14.7  255  16  8   6.2   3.4 |  -9.1  15.6  260  16  8   6.4   3.5
 19500  -8.6  16.5  250  15  8   6.5   3.6 |  -8.2  17.2  260  15  8   6.4   3.5
 19000  -7.6  18.3  250  14  7   6.9   3.8 |  -7.3  18.9  260  15  8   5.3   2.9
 18500  -6.6  20.1  250  14  7   6.9   3.8 |  -6.2  20.8  260  14  7   5.7   3.1
 18000  -5.6  21.9  245  13  7   7.3   4.0 |  -5.3  22.5  260  14  7   6.8   3.8
 17500  -4.5  23.9  245  14  7   7.3   4.0 |  -4.3  24.3  265  13  7   6.8   3.7
 17000  -3.4  25.9  245  14  7   7.4   4.0 |  -3.4  25.9  270  13  7   7.3   4.0
 16500  -2.3  27.9  250  14  7   7.5   4.1 |  -2.3  27.9  270  13  6   7.5   4.1
 16000  -1.3  29.7  250  13  7   7.5   4.1 |  -1.2  29.8  275  12  6   7.7   4.2
 15500  -0.1  31.8  255  13  7   8.1   4.5 |   0.0  32.0  270  12  6   8.4   4.6
 15000   1.1  34.0  255  13  7   8.0   4.4 |   1.3  34.3  270  11  6   8.4   4.6
 14500   2.3  36.1  260  12  6   8.6   4.7 |   2.5  36.5  270  11  6   8.6   4.7
 14000   3.6  38.5  260  12  6   8.7   4.8 |   3.8  38.8  270  11  5   8.6   4.7
 13500   4.8  40.6  265  11  6   8.5   4.7 |   5.1  41.2  270  10  5   8.9   4.9
 13000   6.1  43.0  270  10  5   8.4   4.6 |   6.4  43.5  270  10  5   8.9   4.9
 12500   7.4  45.3  275   9  4   7.9   4.3 |   7.7  45.9  270   9  5   8.6   4.7
 12000   8.4  47.1  285   6  3   7.3   4.0 |   9.0  48.2  280   7  4   8.4   4.6
 11500   9.5  49.1  300   4  2   7.1   3.9 |  10.2  50.4  285   6  3   7.8   4.3
 11000  10.5  50.9  320   3  1   6.8   3.8 |  11.3  52.3  295   4  2   7.3   4.0
 10500  11.5  52.7  005   2  1   6.9   3.8 |  12.4  54.3  315   3  1   6.0   3.3
 10250  12.0  53.6  015   2  1   7.6   4.1 |  12.8  55.0  320   2  1   6.9   3.8
 10000  12.6  54.7  035   2  1   8.0   4.4 |  13.4  56.1  330   2  1   9.0   4.9
  9750  13.2  55.8  055   2  1   8.2   4.5 |  14.1  57.4  340   2  1   8.5   4.7
  9500  13.8  56.8  070   2  1   7.7   4.2 |  14.7  58.5  355   1  1   8.2   4.5
  9250  14.3  57.7  070   2  1   7.1   3.9 |  15.3  59.5  005   1  1   7.8   4.3
  9000  14.9  58.8  070   2  1   7.7   4.2 |  15.8  60.4  015   2  1   8.3   4.6
  8750  15.5  59.9  065   3  1   8.2   4.5 |  16.5  61.7  020   2  1   8.4   4.6
  8500  16.1  61.0  065   3  1   7.4   4.1 |  17.1  62.8  020   2  1   7.6   4.2
  8250  16.6  61.9  060   3  2   6.9   3.8 |  17.6  63.7  020   2  1   7.2   4.0
  8000  17.1  62.8  055   3  2   7.0   3.9 |  18.1  64.6  020   2  1   7.2   3.9
  7750  17.6  63.7  050   4  2   6.0   3.3 |  18.6  65.5  020   2  1   7.7   4.2
  7500  18.0  64.4  050   4  2   3.5   1.9 |  19.2  66.6  015   2  1   8.8   4.8
  7250  18.1  64.6  055   5  2   2.1   1.1 |  19.9  67.8  015   2  1   9.1   5.0
  7000  18.3  64.9  060   5  3   3.1   1.7 |  20.5  68.9  010   2  1   8.8   4.9
  6750  18.5  65.3  060   6  3   2.1   1.2 |  21.2  70.2  010   2  1   9.8   5.4
  6500  18.6  65.5  065   6  3   0.2   0.1 |  21.9  71.4  005   2  1  10.7   5.9
  6250  18.6  65.5  070   5  3  -0.7  -0.4 |  22.7  72.9  360   1  1  10.5   5.7
  6000  18.5  65.3  075   5  3   2.0   1.1 |  23.5  74.3  355   1  1  10.9   6.0
  5750  18.9  66.0  080   5  3  10.7   5.9 |  24.5  76.1  355   1  1  17.4   9.6
  5500  19.9  67.8  080   5  2  16.9   9.3 |  26.1  79.0  355   1  1  27.2  14.9
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/29/2015 at 1500 MDT          |       07/29/2015 at 1800 MDT
                                           |
K index... +8.8  LI... +276.5              | K index... +2.5  LI... +276.7
CAPE... 0.0  CIN... M                      | CAPE... M  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 -64.9 -84.8  230  30 16   1.8   1.0 | -65.7 -86.3  240  35 18   1.4   0.8
 45000 -60.1 -76.2  235  51 26   5.4   3.0 | -60.8 -77.4  245  53 27   6.3   3.5
 40000 -51.4 -60.5  250  70 36   8.1   4.5 | -50.9 -59.6  245  63 32   7.9   4.3
 38000 -46.5 -51.7  245  65 33   8.1   4.4 | -46.1 -51.0  250  61 32   7.9   4.3
 36000 -41.7 -43.1  240  60 31   7.8   4.3 | -41.4 -42.5  250  60 31   7.5   4.1
 34000 -37.0 -34.6  245  52 27   6.9   3.8 | -37.2 -35.0  250  54 28   6.8   3.8
 32000 -32.9 -27.2  245  45 23   7.0   3.8 | -33.1 -27.6  245  47 24   7.1   3.9
 30000 -28.7 -19.7  250  40 21   7.0   3.8 | -28.3 -18.9  250  41 21   7.3   4.0
 29000 -26.6 -15.9  255  38 20   7.0   3.8 | -26.1 -15.0  255  39 20   7.3   4.0
 28000 -24.6 -12.3  255  36 19   6.0   3.3 | -24.0 -11.2  255  37 19   5.9   3.3
 27000 -22.8  -9.0  255  33 17   6.1   3.3 | -22.2  -8.0  255  33 17   6.0   3.3
 26000 -21.0  -5.8  255  30 16   6.1   3.3 | -20.4  -4.7  255  30 15   6.0   3.3
 25000 -19.1  -2.4  250  28 14   6.8   3.8 | -18.6  -1.5  255  27 14   6.7   3.7
 24000 -16.9   1.6  250  25 13   7.6   4.2 | -16.4   2.5  255  24 12   7.1   3.9
 23000 -14.6   5.7  255  23 12   7.6   4.2 | -14.3   6.3  260  21 11   7.1   3.9
 22000 -12.3   9.9  255  21 11   7.0   3.8 | -12.2  10.0  260  19 10   7.0   3.8
 21000 -10.4  13.3  255  18  9   6.5   3.6 | -10.1  13.8  260  16  8   6.9   3.8
 20000  -8.4  16.9  260  16  8   6.5   3.6 |  -8.0  17.6  265  13  7   6.9   3.8
 19500  -7.4  18.7  265  15  8   6.5   3.6 |  -7.0  19.4  265  12  6   6.8   3.7
 19000  -6.0  21.2  265  14  7   6.2   3.4 |  -6.0  21.2  270  11  6   6.3   3.4
 18500  -5.1  22.8  265  14  7   6.2   3.4 |  -5.1  22.8  270  11  6   6.2   3.4
 18000  -4.3  24.3  270  13  7   5.8   3.2 |  -4.1  24.6  275  10  5   7.2   4.0
 17500  -3.4  25.9  270  12  6   5.9   3.2 |  -3.0  26.6  280  10  5   7.4   4.1
 17000  -2.5  27.5  275  12  6   7.2   4.0 |  -1.9  28.6  285   9  5   7.3   4.0
 16500  -1.4  29.5  275  11  6   7.7   4.2 |  -0.9  30.4  285   8  4   6.9   3.8
 16000  -0.3  31.5  280  11  5   7.9   4.4 |   0.1  32.2  290   7  4   6.9   3.8
 15500   0.8  33.4  280  10  5   8.3   4.5 |   1.2  34.2  290   7  3   8.4   4.6
 15000   2.0  35.6  280  10  5   8.3   4.5 |   2.4  36.3  295   6  3   8.4   4.6
 14500   3.3  37.9  285  10  5   8.6   4.7 |   4.3  39.7  310   5  3   8.6   4.7
 14000   4.5  40.1  285  10  5   8.6   4.7 |   5.6  42.1  320   5  3   8.6   4.7
 13500   5.8  42.4  290   9  5   9.0   4.9 |   6.8  44.2  330   5  3   8.9   4.9
 13000   7.1  44.8  290   9  5   9.0   5.0 |   8.2  46.8  340   5  3   8.9   4.9
 12500   8.5  47.3  295   8  4   8.8   4.8 |   9.5  49.1  345   5  3   8.8   4.8
 12000   9.7  49.5  295   8  4   8.7   4.8 |  10.8  51.4  350   5  3   8.8   4.8
 11500  11.0  51.8  300   7  4   8.8   4.8 |  12.1  53.8  355   6  3   8.8   4.8
 11000  12.4  54.3  305   7  3   8.7   4.8 |  13.4  56.1  360   5  3   9.0   5.0
 10500  13.6  56.5  315   6  3   3.9   2.1 |  14.5  58.1  360   5  3   5.0   2.7
 10250  13.8  56.8  315   6  3   5.5   3.0 |  14.9  58.8  360   5  3   8.6   4.7
 10000  14.6  58.3  315   6  3  11.9   6.5 |  15.7  60.3  360   5  3  11.6   6.3
  9750  15.4  59.7  320   5  3  10.5   5.8 |  16.5  61.7  355   5  2  10.3   5.7
  9500  16.1  61.0  325   5  3   7.8   4.3 |  17.2  63.0  355   4  2   7.8   4.3
  9250  16.5  61.7  330   5  2   5.9   3.2 |  17.8  64.0  355   4  2   7.8   4.3
  9000  17.1  62.8  330   5  2   9.1   5.0 |  18.4  65.1  350   4  2   9.7   5.3
  8750  17.8  64.0  335   4  2  10.0   5.5 |  19.1  66.4  345   4  2   9.2   5.0
  8500  18.5  65.3  335   4  2   8.9   4.9 |  19.8  67.6  340   3  2   8.3   4.5
  8250  19.1  66.4  335   4  2   8.0   4.4 |  20.3  68.5  335   3  2   8.0   4.4
  8000  19.7  67.5  335   4  2   9.5   5.2 |  20.9  69.6  330   3  2   8.3   4.6
  7750  20.5  68.9  335   4  2  10.7   5.9 |  21.5  70.7  325   3  1   8.8   4.9
  7500  21.3  70.3  335   4  2  10.0   5.5 |  22.2  72.0  320   3  1   9.3   5.1
  7250  22.0  71.6  335   4  2   9.8   5.4 |  22.9  73.2  315   2  1   9.2   5.1
  7000  22.7  72.9  330   3  2  10.0   5.5 |  23.5  74.3  310   2  1   9.7   5.3
  6750  23.5  74.3  330   3  2  10.5   5.7 |  24.3  75.7  305   2  1  10.1   5.6
  6500  24.3  75.7  325   3  2  10.7   5.9 |  25.1  77.2  300   2  1  10.1   5.5
  6250  25.1  77.2  325   3  2  10.6   5.8 |  25.8  78.4  295   2  1   9.9   5.4
  6000  25.9  78.6  320   3  2  10.6   5.8 |  26.6  79.9  290   2  1  10.6   5.8
  5750  26.8  80.2  320   3  2  17.5   9.6 |  27.4  81.3  290   2  1  10.7   5.9
  5500  28.6  83.5  325   3  2  28.8  15.8 |  28.1  82.6  295   2  1   9.9   5.4
  5250     M     M    M   M  M     M     M |  28.8  83.8  300   2  1  10.6   5.8
  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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