Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 271253
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0652 MDT Monday, April 27, 2015

This forecast is for Monday, April 27, 2015:

If the trigger temperature of 54.6 F/12.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 277 ft/min (1.4 m/s)
   Maximum height of thermals.................. 13801 ft MSL (8962 ft AGL)

Forecast maximum temperature................... 66.0 F/19.3 C
Time of trigger temperature.................... 1100 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................. 10643 ft MSL (5804 ft AGL)
Thermal soaring outlook for Tuesday 04/28...... Good

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

Remarks...

Sunrise/Sunset.................... 06:21:14 / 20:02:08 MDT
Total possible sunshine........... 13 hr 40 min 54 sec (820 min 54 sec)
Altitude of sun at 13:11:51 MDT... 64.80 degrees

Upper air data from rawinsonde observation taken on 04/27/2015 at 0600 MDT

Freezing level.................. 9118 ft MSL (4279 ft AGL)
Convective condensation level... 10263 ft MSL (5424 ft AGL)
Lifted condensation level....... 12329 ft MSL (7490 ft AGL)
Lifted index.................... -1.1
K index......................... +22.3

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  -58.7 -73.7   360   40   21   4.6   2.5  103.5 218.3    48.2      M    M
 45000  -56.3 -69.3   005   43   22  -0.4  -0.2   82.6 180.6    38.8      M    M
 40000  -55.1 -67.2   020   54   28  -1.9  -1.0   61.4 142.5    27.7      M    M
 38000  -54.8 -66.6   010   71   36   4.0   2.2   51.9 125.4    22.2      M    M
 36000  -52.9 -63.2   010   61   32  -3.1  -1.7   46.0 114.8    18.7      M    M
 34000  -53.3 -63.9   350   34   17  -7.6  -4.2   37.1  98.7    12.9      M    M
 32000  -50.4 -58.7   025   14    7   8.1   4.4   32.9  91.3    10.2      M    M
 30000  -45.4 -49.7   030   17    9   9.3   5.1   31.8  89.2     9.6      M    M
 29000  -42.9 -45.2   010   15    8   7.9   4.3   31.2  88.2     9.3      M    M
 28000  -40.6 -41.1   010   13    7   7.9   4.3   30.3  86.6     8.8      M    M
 27000  -38.2 -36.8   015   11    6   7.9   4.3   29.6  85.3     8.3      M    M
 26000  -35.8 -32.4   020   10    5   8.6   4.7   29.0  84.2     7.9      M    M
 25000  -33.2 -27.8   025    8    4   8.8   4.8   28.7  83.6     7.7      M    M
 24000  -30.5 -22.9   040    9    5   8.8   4.8   28.3  82.9     7.5      M    M
 23000  -27.9 -18.2   040    8    4   8.8   4.9   27.9  82.2     7.3      M    M
 22000  -25.2 -13.4   045    8    4   8.8   4.8   27.6  81.7     7.2      M    M
 21000  -22.6  -8.7   045    7    4   8.7   4.8   27.2  81.0     6.9      M    M
 20000  -19.6  -3.3   050    6    3   6.9   3.8   26.6  79.9     6.4      M    M
 19500  -18.5  -1.3   050    4    2   7.0   3.8   26.1  79.0     6.0      M    M
 19000  -17.5   0.5   050    5    2   7.1   3.9   25.7  78.2     5.7      M    M
 18500  -16.5   2.3   050    9    5   8.0   4.4   25.2  77.3     5.2      M    M
 18000  -15.1   4.8   055   10    5   9.3   5.1   25.1  77.1     5.2      M    M
 17500  -13.9   7.0   060   11    6   6.1   3.3   24.8  76.6     4.9      M    M
 17000  -13.3   8.1   060   12    6   1.4   0.8   23.8  74.9     4.1      M    M
 16500  -13.0   8.6   050   12    6   6.4   3.5   22.6  72.7     3.0      M    M
 16000  -11.8  10.8   045   12    6   7.8   4.3   22.2  72.0     2.7      M    M
 15500  -10.6  12.9   070   11    6   5.5   3.0   21.9  71.5     2.4      M    M
 15000  -10.4  13.3   090   13    7   0.7   0.4   20.6  69.1     1.2      M    M
 14500   -9.9  14.2   090   10    5   7.8   4.3   19.5  67.2     0.2      M    M
 14000   -8.6  16.5   085    8    4   8.7   4.8   19.4  66.9     0.1      M    M
 13500   -7.4  18.7   105    9    5   7.6   4.2   19.2  66.5    -0.1    642  3.3
 13000   -6.3  20.7   120   11    6   7.2   3.9   18.8  65.8    -0.6    596  3.0
 12500   -5.3  22.5   115    8    4   7.1   3.9   18.3  65.0    -1.0    550  2.8
 12000   -4.2  24.4   100    6    3   7.2   3.9   17.9  64.3    -1.4    504  2.6
 11500   -3.2  26.2   100    3    2   7.3   4.0   17.5  63.5    -1.9    459  2.3
 11000   -2.2  28.0   090    1    1   8.3   4.6   17.1  62.7    -2.3    413  2.1
 10500   -1.9  28.6   065    3    1  -7.4  -4.1   15.8  60.5    -3.5    390  2.0
 10250   -2.4  27.7   060    3    2   0.9   0.5   14.6  58.3    -4.8    397  2.0
 10000   -1.8  28.8   060    4    2  11.6   6.4   14.5  58.1    -4.9    371  1.9
  9750   -1.1  30.0   050    3    2   5.6   3.1   14.5  58.0    -4.9    343  1.7
  9500   -0.9  30.4   040    3    1   4.6   2.5   14.0  57.1    -5.5    329  1.7
  9250   -0.3  31.5   025    2    1   7.6   4.1   13.7  56.7    -5.7    306  1.6
  9000    0.2  32.4   005    2    1   6.8   3.7   13.5  56.4    -5.9    283  1.4
  8750    0.7  33.3   040    3    2   7.0   3.8   13.3  56.0    -6.1    260  1.3
  8500    1.2  34.2   055    6    3   6.9   3.8   13.1  55.6    -6.4    237  1.2
  8250    1.7  35.1   060    8    4   6.9   3.8   12.9  55.2    -6.6    214  1.1
  8000    2.3  36.1   065   11    5   6.9   3.8   12.7  54.8    -6.8    191  1.0
  7750    2.8  37.0   055   11    6   6.9   3.8   12.4  54.4    -7.1    168  0.9
  7500    3.3  37.9   045   12    6   6.9   3.8   12.2  54.0    -7.3    145  0.7
  7250    3.8  38.8   035   12    6   7.0   3.8   12.0  53.6    -7.5    122  0.6
  7000    4.3  39.7   025   14    7   6.8   3.7   11.8  53.2    -7.8    100  0.5
  6750    4.9  40.8   025   13    7   8.1   4.5   11.6  52.8    -8.0     76  0.4
  6500    5.5  41.9   025   11    6   9.4   5.1   11.5  52.7    -8.1     49  0.2
  6250    6.2  43.2   020   10    5   9.0   5.0   11.5  52.7    -8.1     21  0.1
  6000    6.9  44.4   020    8    4   9.1   5.0   11.4  52.6    -8.2      M    M
  5750    7.5  45.5   020    7    4   9.2   5.0   11.4  52.5    -8.3      M    M
  5500    8.2  46.8   015    6    3   8.8   4.8   11.3  52.4    -8.4      M    M
  5250    8.8  47.8   010    5    3   8.4   4.6   11.2  52.2    -8.5      M    M
  5000    9.4  48.9   005    4    2   5.9   3.3   11.1  51.9    -8.7      M    M

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

           04/27/2015 at 0900 MDT          |       04/27/2015 at 1200 MDT
                                           |
K index... +24.7  LI... +274.5             | K index... +21.4  LI... +273.6
CAPE... +19.2  CIN... -37.0                | CAPE... +34.1  CIN... -18.4
                                           |
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 -58.0 -72.4  010  43 22   1.4   0.8 | -58.4 -73.1  010  42 22   2.0   1.1
 45000 -55.8 -68.4  010  50 26   1.0   0.5 | -55.4 -67.7  010  49 25   1.0   0.5
 40000 -54.3 -65.7  020  61 31   1.0   0.6 | -53.8 -64.8  020  54 28   1.1   0.6
 38000 -53.5 -64.3  020  60 31   1.6   0.9 | -53.1 -63.6  020  55 28   1.3   0.7
 36000 -52.5 -62.5  015  55 28   1.6   0.9 | -52.3 -62.1  020  56 29   1.3   0.7
 34000 -51.3 -60.3  015  47 24   4.4   2.4 | -51.0 -59.8  020  53 27   5.3   2.9
 32000 -48.8 -55.8  015  30 16   4.2   2.3 | -47.5 -53.5  020  35 18   5.2   2.8
 30000 -45.2 -49.4  020  16  8   8.2   4.5 | -44.0 -47.2  020  22 11   7.5   4.1
 29000 -42.7 -44.9  025  15  8   8.3   4.5 | -41.7 -43.1  025  18  9   7.5   4.1
 28000 -40.3 -40.5  030  14  7   8.3   4.5 | -39.5 -39.1  030  15  8   7.5   4.1
 27000 -37.8 -36.0  035  14  7   8.3   4.5 | -37.2 -35.0  035  12  6   8.2   4.5
 26000 -35.3 -31.5  030  12  6   8.3   4.6 | -34.7 -30.5  030  12  6   8.2   4.5
 25000 -32.8 -27.0  030  10  5   8.3   4.6 | -32.3 -26.1  020  12  6   8.2   4.5
 24000 -30.3 -22.5  030   9  4   8.7   4.8 | -29.8 -21.6  015  12  6   8.5   4.7
 23000 -27.7 -17.9  040   8  4   8.9   4.9 | -27.2 -17.0  015  11  6   8.7   4.8
 22000 -25.0 -13.0  050   7  4   9.0   4.9 | -24.6 -12.3  005   9  5   8.7   4.8
 21000 -22.4  -8.3  060   7  4   7.7   4.2 | -22.1  -7.8  005   8  4   8.1   4.5
 20000 -20.1  -4.2  070   8  4   7.7   4.2 | -19.6  -3.3  020   6  3   8.2   4.5
 19500 -19.0  -2.2  075   8  4   7.8   4.3 | -18.4  -1.1  025   6  3   8.2   4.5
 19000 -17.8  -0.0  075   9  4   7.9   4.3 | -17.2   1.0  040   5  3   8.3   4.6
 18500 -16.8   1.8  080   9  5   5.6   3.1 | -16.0   3.2  045   5  3   6.9   3.8
 18000 -16.0   3.2  075   8  4   5.0   2.8 | -15.0   5.0  045   5  3   6.7   3.7
 17500 -15.3   4.5  075   7  4   5.0   2.7 | -14.0   6.8  045   5  2   6.3   3.5
 17000 -14.6   5.7  070   7  3   4.9   2.7 | -13.2   8.2  040   5  3   5.3   2.9
 16500 -13.9   7.0  060   6  3   4.8   2.6 | -12.5   9.5  035   6  3   5.3   2.9
 16000 -13.1   8.4  050   6  3   7.1   3.9 | -11.6  11.1  040   6  3   6.6   3.6
 15500 -12.1  10.2  040   5  3   7.0   3.9 | -10.2  13.6  045   7  4   6.5   3.6
 15000 -11.0  12.2  025   5  2   7.7   4.2 |  -9.3  15.3  050   7  4   6.5   3.6
 14500  -9.9  14.2  025   5  3   7.9   4.3 |  -8.3  17.1  055   8  4   6.5   3.6
 14000  -8.1  17.4  030   6  3   7.4   4.1 |  -7.3  18.9  060   9  5   6.4   3.5
 13500  -7.1  19.2  030   6  3   7.5   4.1 |  -6.4  20.5  065  10  5   6.4   3.5
 13000  -6.0  21.2  030   6  3   6.9   3.8 |  -5.4  22.3  065  10  5   6.9   3.8
 12500  -5.0  23.0  030   5  3   6.9   3.8 |  -4.4  24.1  060  10  5   6.9   3.8
 12000  -4.0  24.8  030   4  2   6.8   3.7 |  -3.4  25.9  060  10  5   7.2   4.0
 11500  -3.0  26.6  030   4  2   6.8   3.7 |  -2.3  27.9  050  10  5   7.3   4.0
 11000  -2.1  28.2  025   4  2   6.4   3.5 |  -1.3  29.7  050  11  5   6.6   3.6
 10500  -1.1  30.0  025   3  2   7.0   3.8 |  -0.3  31.5  045  10  5   7.2   3.9
 10250  -0.7  30.7  025   3  2   3.8   2.1 |   0.1  32.2  045  10  5   4.1   2.3
 10000  -0.5  31.1  020   3  2   4.6   2.5 |   0.4  32.7  040  10  5   5.1   2.8
  9750   0.1  32.2  020   3  2   8.1   4.5 |   0.9  33.6  040  10  5   8.7   4.7
  9500   0.6  33.1  020   3  2   7.8   4.3 |   1.5  34.7  035  10  5   8.1   4.5
  9250   1.2  34.2  025   3  2   5.6   3.1 |   2.0  35.6  035   9  5   5.6   3.1
  9000   1.5  34.7  030   4  2   4.8   2.6 |   2.3  36.1  030   9  5   5.9   3.2
  8750   1.9  35.4  030   4  2   6.9   3.8 |   2.9  37.2  030   8  4   8.6   4.7
  8500   2.4  36.3  035   4  2   6.4   3.5 |   3.5  38.3  025   8  4   8.0   4.4
  8250   2.8  37.0  035   5  3   6.4   3.5 |   4.1  39.4  020   7  4   8.3   4.5
  8000   3.3  37.9  040   6  3   6.1   3.4 |   4.6  40.3  020   7  4   8.8   4.9
  7750   3.7  38.7  040   7  4   5.8   3.2 |   5.3  41.5  020   7  4   9.6   5.3
  7500   4.1  39.4  045   8  4   5.7   3.1 |   6.0  42.8  020   7  3   9.9   5.4
  7250   4.5  40.1  045   7  4   5.7   3.2 |   6.8  44.2  020   6  3  10.0   5.5
  7000   4.9  40.8  045   6  3   5.5   3.0 |   7.5  45.5  015   6  3   9.8   5.4
  6750   5.2  41.4  045   5  3   5.1   2.8 |   8.2  46.8  015   6  3   9.9   5.4
  6500   5.6  42.1  045   4  2   6.0   3.3 |   9.0  48.2  015   6  3  10.8   6.0
  6250   6.1  43.0  050   3  2   7.1   3.9 |   9.9  49.8  015   5  3  11.9   6.6
  6000   6.6  43.9  060   2  1   5.8   3.2 |  10.7  51.3  015   5  3   9.8   5.4
  5750   7.0  44.6  075   2  1   7.3   4.0 |  11.4  52.5  010   5  2  11.8   6.5
  5500   7.6  45.7  070   2  1  10.2   5.6 |  12.5  54.5  010   5  3  15.9   8.7
  5250   8.3  46.9  065   2  1   8.3   4.5 |  13.6  56.5  010   5  3  12.6   6.9
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/27/2015 at 1500 MDT          |       04/27/2015 at 1800 MDT
                                           |
K index... +20.4  LI... +272.5             | K index... +24.1  LI... +272.1
CAPE... +126.1  CIN... -10.1               | CAPE... +138.8  CIN... -4.5
                                           |
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 -58.6 -73.5  010  41 21   1.8   1.0 | -59.5 -75.1  010  42 22   2.2   1.2
 45000 -56.0 -68.8  010  49 25   0.6   0.3 | -56.3 -69.3  010  48 25   1.4   0.7
 40000 -54.9 -66.8  020  53 27   0.8   0.4 | -54.0 -65.2  015  47 24   1.4   0.8
 38000 -53.7 -64.7  020  51 26   2.5   1.4 | -53.1 -63.6  015  44 23   1.7   0.9
 36000 -52.2 -62.0  025  48 25   2.5   1.4 | -52.1 -61.8  015  40 21   1.7   0.9
 34000 -50.2 -58.4  025  43 22   5.4   3.0 | -50.3 -58.5  015  35 18   5.7   3.1
 32000 -47.0 -52.6  025  34 18   5.5   3.0 | -46.9 -52.4  020  28 14   5.7   3.1
 30000 -43.4 -46.1  025  24 13   7.3   4.0 | -43.1 -45.6  025  21 11   7.7   4.3
 29000 -41.2 -42.2  025  19 10   7.4   4.0 | -40.8 -41.4  020  18  9   7.8   4.3
 28000 -39.0 -38.2  020  14  7   7.4   4.0 | -38.4 -37.1  010  15  7   7.8   4.3
 27000 -36.1 -33.0  020  10  5   8.2   4.5 | -35.5 -31.9  360  12  6   8.0   4.4
 26000 -33.7 -28.7  020  10  5   8.2   4.5 | -33.1 -27.6  360  10  5   8.0   4.4
 25000 -31.2 -24.2  025  10  5   8.2   4.5 | -30.7 -23.3  005   9  5   8.0   4.4
 24000 -28.8 -19.8  025  10  5   7.9   4.4 | -28.3 -18.9  005   8  4   8.1   4.4
 23000 -26.5 -15.7  020   9  5   8.0   4.4 | -25.9 -14.6  005   8  4   8.1   4.4
 22000 -24.1 -11.4  015   8  4   8.0   4.4 | -23.5 -10.3  005   8  4   8.1   4.4
 21000 -21.7  -7.1  010   7  4   8.2   4.5 | -21.2  -6.2  360   7  4   7.4   4.0
 20000 -19.3  -2.7  010   6  3   8.2   4.5 | -19.0  -2.2  355   6  3   7.4   4.1
 19500 -18.0  -0.4  015   5  3   8.2   4.5 | -17.9  -0.2  350   6  3   7.4   4.1
 19000 -16.8   1.8  015   4  2   8.3   4.6 | -16.8   1.8  345   5  3   7.5   4.1
 18500 -15.7   3.7  015   4  2   6.9   3.8 | -15.8   3.6  345   5  3   6.5   3.6
 18000 -14.6   5.7  020   4  2   7.0   3.8 | -14.8   5.4  355   5  2   6.6   3.6
 17500 -13.6   7.5  020   4  2   6.5   3.6 | -13.8   7.2  360   5  2   6.7   3.7
 17000 -12.7   9.1  030   4  2   6.1   3.4 | -12.8   9.0  010   4  2   6.8   3.7
 16500 -11.9  10.6  035   4  2   6.2   3.4 | -11.8  10.8  020   4  2   6.8   3.7
 16000 -10.9  12.4  050   4  2   6.7   3.7 | -10.8  12.6  025   4  2   7.3   4.0
 15500  -9.9  14.2  070   4  2   6.6   3.6 |  -9.7  14.5  030   3  2   7.3   4.0
 15000  -8.9  16.0  090   4  2   7.5   4.1 |  -8.6  16.5  030   4  2   7.5   4.1
 14500  -7.8  18.0  095   4  2   7.5   4.1 |  -7.5  18.5  025   5  3   7.5   4.1
 14000  -6.7  19.9  100   4  2   7.5   4.1 |  -6.4  20.5  025   7  3   7.4   4.1
 13500  -5.6  21.9  085   4  2   7.5   4.1 |  -4.8  23.4  025  10  5   7.4   4.1
 13000  -4.0  24.8  060   5  3   7.3   4.0 |  -3.7  25.3  025  11  6   7.4   4.1
 12500  -2.9  26.8  045   7  4   7.3   4.0 |  -2.7  27.1  025  13  7   7.3   4.0
 12000  -1.8  28.8  035   9  4   7.2   4.0 |  -1.6  29.1  025  14  7   8.8   4.8
 11500  -0.8  30.6  025  10  5   7.2   4.7 |  -0.3  31.5  025  14  7   8.6   4.7
 11000   0.3  32.5  020  11  6   7.9   4.4 |   1.0  33.8  025  13  7   9.7   5.3
 10500   1.4  34.5  015  11  6   8.1   4.4 |   2.4  36.3  025  13  7  10.4   5.7
 10250   1.9  35.4  010  11  6   5.4   2.9 |   3.1  37.6  025  13  7   6.6   3.6
 10000   2.2  36.0  010  11  6   7.0   3.8 |   3.5  38.3  025  13  7   7.5   4.1
  9750   2.9  37.2  010  11  5  10.4   5.7 |   4.3  39.7  025  12  6  12.0   6.6
  9500   3.6  38.5  005  10  5   9.5   5.2 |   5.1  41.2  025  12  6  10.9   6.0
  9250   4.3  39.7  005  10  5   8.6   4.7 |   5.9  42.6  025  12  6   8.8   4.8
  9000   4.9  40.8  360  10  5   9.0   4.9 |   6.5  43.7  025  11  6   8.5   4.7
  8750   5.6  42.1  360  10  5  10.1   5.6 |   7.2  45.0  025  11  6  10.3   5.7
  8500   6.3  43.3  360  10  5   9.9   5.4 |   8.0  46.4  025  10  5   9.8   5.4
  8250   7.0  44.6  360   9  5  10.1   5.6 |   8.7  47.7  020  10  5  10.0   5.5
  8000   7.8  46.0  360   9  5  10.2   5.6 |   9.4  48.9  020   9  5   9.8   5.4
  7750   8.5  47.3  360   9  5  10.2   5.6 |  10.2  50.4  020   9  5   9.7   5.3
  7500   9.3  48.7  355   9  4  10.1   5.5 |  10.9  51.6  020   9  4   9.8   5.4
  7250  10.0  50.0  355   8  4   9.9   5.4 |  11.6  52.9  020   8  4  10.0   5.5
  7000  10.8  51.4  355   8  4   9.8   5.4 |  12.4  54.3  020   8  4   9.9   5.4
  6750  11.5  52.7  355   8  4  10.0   5.5 |  13.1  55.6  020   8  4   9.7   5.3
  6500  12.3  54.1  355   8  4  10.8   5.9 |  13.8  56.8  020   7  4  10.3   5.6
  6250  13.1  55.6  355   7  4  11.6   6.4 |  14.6  58.3  020   7  4  10.8   6.0
  6000  14.0  57.2  350   7  4  10.1   5.6 |  15.4  59.7  020   6  3  10.3   5.7
  5750  14.7  58.5  350   7  3  12.1   6.6 |  16.2  61.2  020   6  3   9.4   5.2
  5500  15.8  60.4  350   7  4  15.8   8.7 |  16.8  62.2  020   6  3   9.2   5.0
  5250  16.9  62.4  350   7  4  13.7   7.5 |  17.5  63.5  020   6  3   9.5   5.2
  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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