Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 251215
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0615 MDT Monday, August 25, 2014

This forecast is for Monday, August 25, 2014:

If the trigger temperature of 73.1 F/22.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 689 ft/min (3.5 m/s)
   Maximum height of thermals.................. 15666 ft MSL (10827 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1000 MDT
Time of overdevelopment........................ 1500 MDT
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................. 10291 ft MSL (5452 ft AGL)
Thermal soaring outlook for Tuesday 08/26...... Good

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

Remarks...

Sunrise/Sunset.................... 06:36:30 / 19:56:26 MDT
Total possible sunshine........... 13 hr 19 min 56 sec (799 min 56 sec)
Altitude of sun at 13:16:04 MDT... 61.46 degrees

Upper air data from rawinsonde observation taken on 08/25/2014 at 0600 MDT

Freezing level.................. 14212 ft MSL (9373 ft AGL)
Convective condensation level... 13193 ft MSL (8354 ft AGL)
Lifted condensation level....... 13935 ft MSL (9096 ft AGL)
Lifted index.................... -4.2
K index......................... +33.0

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  -62.2 -80.0   230   47   24   2.0   1.1   92.3 198.2    36.3      M    M
 45000  -59.0 -74.2   240   67   34   3.2   1.7   73.1 163.5    27.0      M    M
 40000  -55.0 -67.0   240   75   38   1.0   0.5   56.4 133.6    17.9      M    M
 38000  -51.8 -61.2   240   71   36   6.5   3.6   52.2 125.9    15.5      M    M
 36000  -47.4 -53.3   235   66   34   6.4   3.5   49.2 120.6    13.8      M    M
 34000  -43.2 -45.8   235   62   32   8.5   4.7   46.7 116.1    12.4      M    M
 32000  -38.1 -36.6   240   59   30   9.8   5.3   45.8 114.4    12.1      M    M
 30000  -34.4 -29.9   240   52   27   7.8   4.3   42.9 109.3    10.2      M    M
 29000  -31.9 -25.4   240   47   24   8.4   4.6   42.4 108.3     9.9      M    M
 28000  -29.4 -20.9   235   42   22   8.4   4.6   41.9 107.4     9.7      M    M
 27000  -27.0 -16.6   235   46   23   6.7   3.7   41.2 106.1     9.2      M    M
 26000  -25.7 -14.3   235   49   25   9.8   5.4   39.2 102.6     7.7      M    M
 25000  -22.9  -9.2   235   53   27   6.4   3.5   39.1 102.3     7.6      M    M
 24000  -21.0  -5.8   235   50   26   7.6   4.2   37.8 100.1     6.7      M    M
 23000  -18.5  -1.3   235   45   23   8.3   4.6   37.3  99.1     6.3      M    M
 22000  -16.0   3.2   230   40   20   8.0   4.4   36.7  98.1     6.0      M    M
 21000  -13.9   7.0   230   35   18   7.0   3.9   35.8  96.5     5.2      M    M
 20000  -11.8  10.8   230   37   19   7.4   4.1   34.9  94.8     4.4      M    M
 19500  -10.7  12.7   230   35   18   6.3   3.5   34.5  94.1     4.0      M    M
 19000   -9.8  14.4   230   32   16   7.5   4.1   33.0  91.5     2.8      M    M
 18500   -8.7  16.3   230   32   16   9.8   5.4   32.7  90.9     2.5      M    M
 18000   -7.5  18.5   230   32   16   4.4   2.4   32.4  90.3     2.2      M    M
 17500   -6.8  19.8   225   32   16   7.7   4.2   31.7  89.0     1.5      M    M
 17000   -5.6  21.9   225   32   16   8.3   4.5   31.4  88.5     1.2      M    M
 16500   -4.7  23.5   225   32   16   5.8   3.2   30.8  87.5     0.6      M    M
 16000   -3.7  25.3   225   32   16   7.3   4.0   30.4  86.7     0.2      M    M
 15500   -2.7  27.1   225   31   16   6.4   3.5   29.9  85.8    -0.3    871  4.4
 15000   -1.7  28.9   225   29   15   7.8   4.3   29.5  85.1    -0.7    825  4.2
 14500   -0.7  30.7   230   28   14   9.0   4.9   29.2  84.5    -1.2    780  4.0
 14000    0.7  33.3   230   27   14   9.9   5.4   29.2  84.5    -1.2    723  3.7
 13500    2.1  35.8   230   28   14   8.3   4.6   29.1  84.3    -1.4    668  3.4
 13000    3.3  37.9   230   29   15   8.5   4.7   28.9  84.0    -1.6    616  3.1
 12500    4.6  40.3   230   30   15   8.5   4.7   28.7  83.6    -1.8    563  2.9
 12000    5.8  42.4   230   31   16   8.5   4.7   28.5  83.4    -2.0    510  2.6
 11500    7.1  44.8   230   26   14   8.5   4.7   28.3  83.0    -2.2    458  2.3
 11000    8.4  47.1   225   22   11   8.3   4.6   28.1  82.6    -2.4    405  2.1
 10500    9.6  49.3   220   19   10   5.8   3.2   27.9  82.2    -2.6    352  1.8
 10250    9.9  49.8   215   18    9   4.6   2.5   27.4  81.4    -3.1    337  1.7
 10000   10.3  50.5   205   16    8   6.4   3.5   27.2  80.9    -3.4    316  1.6
  9750   10.8  51.4   200   15    8   8.0   4.4   26.9  80.4    -3.7    296  1.5
  9500   11.2  52.2   190   14    7   0.2   0.1   26.6  80.0    -4.0    276  1.4
  9250   10.7  51.3   180   13    7  -7.3  -4.0   25.4  77.7    -5.2    282  1.4
  9000   10.5  50.9   170   13    7   2.2   1.2   24.4  75.9    -6.1    281  1.4
  8750   11.0  51.8   170   11    6   6.3   3.4   24.1  75.4    -6.4    260  1.3
  8500   11.4  52.5   165    8    4   6.1   3.3   23.8  74.8    -6.7    240  1.2
  8250   11.8  53.2   165    6    3  -1.0  -0.6   23.3  74.0    -7.1    222  1.1
  8000   11.5  52.7   155    3    2  -0.0  -0.0   22.3  72.1    -8.2    224  1.1
  7750   11.9  53.4   120    2    1   9.0   4.9   22.0  71.7    -8.5    203  1.0
  7500   12.5  54.5   070    3    1   8.4   4.6   21.9  71.5    -8.6    177  0.9
  7250   13.2  55.8   045    4    2   8.6   4.7   21.9  71.3    -8.7    151  0.8
  7000   13.8  56.8   035    6    3   8.6   4.7   21.8  71.2    -8.8    124  0.6
  6750   14.4  57.9   025    6    3   8.6   4.7   21.7  71.0    -9.0     98  0.5
  6500   15.0  59.0   015    6    3   8.6   4.7   21.6  70.9    -9.1     72  0.4
  6250   15.6  60.1   005    6    3   8.6   4.7   21.5  70.7    -9.2     46  0.2
  6000   16.3  61.3   355    6    3   8.5   4.7   21.4  70.6    -9.4     20  0.1
  5750   16.9  62.4   345    6    3   8.7   4.8   21.3  70.4    -9.5      M    M
  5500   17.3  63.1   330    5    3   1.0   0.6   21.1  69.9    -9.8      M    M
  5250   17.0  62.6   320    5    3  -6.4  -3.5   20.0  68.0   -10.9      M    M
  5000   16.6  61.9   305    5    3   0.1   0.1   19.0  66.1   -12.1      M    M

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

           08/25/2014 at 0900 MDT          |       08/25/2014 at 1200 MDT
                                           |
K index... +31.3  LI... -1.7               | K index... +29.9  LI... -3.1
CAPE... +419.7  CIN... -19.4               | CAPE... +861.3  CIN... -11.8
                                           |
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 -62.0 -79.6  240  43 22   0.2   0.1 | -61.4 -78.5  240  45 23   0.3   0.2
 45000 -60.3 -76.5  240  71 37   3.9   2.1 | -59.9 -75.8  240  71 37   3.0   1.7
 40000 -54.4 -65.9  245  76 39   5.5   3.0 | -55.3 -67.5  245  75 39   5.5   3.0
 38000 -51.1 -60.0  245  71 37   5.6   3.1 | -51.7 -61.1  245  70 36   5.9   3.2
 36000 -47.7 -53.9  240  67 35   5.6   3.1 | -48.2 -54.8  240  64 33   5.9   3.2
 34000 -43.7 -46.7  245  61 32   7.2   3.9 | -43.5 -46.3  240  56 29   7.3   4.0
 32000 -38.9 -38.0  245  54 28   7.2   3.9 | -39.1 -38.4  240  48 25   7.3   4.0
 30000 -34.4 -29.9  245  48 25   7.5   4.1 | -34.4 -29.9  235  42 22   7.9   4.3
 29000 -32.2 -26.0  245  44 23   7.5   4.1 | -32.1 -25.8  235  39 20   7.9   4.3
 28000 -29.9 -21.8  245  41 21   7.3   4.0 | -29.7 -21.5  235  36 19   7.6   4.2
 27000 -27.9 -18.2  245  41 21   6.7   3.7 | -27.6 -17.7  235  35 18   6.8   3.7
 26000 -25.9 -14.6  245  41 21   6.7   3.7 | -25.6 -14.1  235  35 18   6.8   3.7
 25000 -23.9 -11.0  245  41 21   6.6   3.6 | -23.6 -10.5  240  34 18   6.8   3.7
 24000 -21.5  -6.7  245  40 21   8.7   4.8 | -21.2  -6.2  240  34 17   8.3   4.6
 23000 -18.9  -2.0  245  40 20   8.7   4.8 | -18.7  -1.7  240  33 17   8.3   4.6
 22000 -16.2   2.8  245  39 20   8.8   4.8 | -16.2   2.8  240  32 16   8.3   4.6
 21000 -13.9   7.0  245  36 19   7.4   4.1 | -13.9   7.0  240  31 16   7.8   4.3
 20000 -11.8  10.8  245  34 17   7.5   4.1 | -11.5  11.3  240  30 15   7.8   4.3
 19500 -10.7  12.7  245  32 17   7.5   4.1 | -10.4  13.3  240  30 15   7.8   4.3
 19000  -9.5  14.9  250  31 16   7.8   4.3 |  -9.2  15.4  240  29 15   8.2   4.5
 18500  -8.3  17.1  245  31 16   7.8   4.3 |  -8.0  17.6  240  29 15   8.2   4.5
 18000  -7.2  19.0  245  31 16   7.7   4.2 |  -6.7  19.9  240  29 15   8.1   4.4
 17500  -6.2  20.8  245  30 16   5.7   3.1 |  -5.7  21.7  240  29 15   6.7   3.7
 17000  -5.4  22.3  240  30 16   5.9   3.2 |  -4.7  23.5  240  29 15   6.9   3.8
 16500  -4.6  23.7  240  30 15   5.2   2.9 |  -3.8  25.2  240  28 15   5.8   3.2
 16000  -3.9  25.0  235  29 15   5.3   2.9 |  -2.6  27.3  235  28 14   5.9   3.2
 15500  -3.2  26.2  235  29 15   6.1   3.3 |  -1.8  28.8  235  27 14   5.9   3.2
 15000  -1.8  28.8  230  28 14   7.1   3.9 |  -1.0  30.2  235  26 13   6.0   3.3
 14500  -0.8  30.6  230  27 14   8.8   4.8 |  -0.2  31.6  230  24 12   6.9   3.8
 14000   0.6  33.1  230  26 13   9.3   5.1 |   0.7  33.3  230  22 11   7.2   4.0
 13500   1.9  35.4  230  25 13   8.5   4.6 |   1.7  35.1  225  20 10   8.2   4.5
 13000   3.0  37.4  230  24 12   7.5   4.1 |   3.0  37.4  225  19 10   9.1   5.0
 12500   4.0  39.2  230  22 11   8.1   4.4 |   4.3  39.7  225  17  9   8.8   4.8
 12000   5.4  41.7  230  20 10   9.4   5.2 |   5.5  41.9  220  15  8   8.2   4.5
 11500   6.7  44.1  230  18  9   9.3   5.1 |   6.7  44.1  220  14  7   8.4   4.6
 11000   8.1  46.6  230  16  8   8.9   4.9 |   8.0  46.4  220  12  6   8.7   4.8
 10500   9.5  49.1  230  14  7   4.9   2.7 |   9.4  48.9  220  11  6   5.5   3.0
 10250   9.7  49.5  230  14  7   5.7   3.1 |   9.7  49.5  220  11  6   6.4   3.5
 10000  10.5  50.9  230  13  7  11.5   6.3 |  10.4  50.7  220  10  5  11.3   6.2
  9750  11.2  52.2  230  12  6  10.4   5.7 |  11.2  52.2  215  10  5  10.4   5.7
  9500  12.0  53.6  225  11  6   9.0   4.9 |  12.0  53.6  215   9  5   9.3   5.1
  9250  12.5  54.5  225  10  5   6.7   3.7 |  12.6  54.7  215   9  5   7.9   4.4
  9000  13.0  55.4  220   9  4   7.5   4.1 |  13.2  55.8  210   9  4   8.9   4.9
  8750  13.6  56.5  210   8  4   8.2   4.5 |  13.9  57.0  210   8  4   9.4   5.1
  8500  14.2  57.6  200   7  3   7.0   3.9 |  14.5  58.1  205   8  4   8.5   4.7
  8250  14.6  58.3  190   6  3   5.8   3.2 |  15.1  59.2  200   7  4   7.6   4.1
  8000  15.1  59.2  180   6  3   6.4   3.5 |  15.7  60.3  200   7  4   8.5   4.7
  7750  15.6  60.1  170   6  3   6.8   3.7 |  16.3  61.3  200   7  4   9.2   5.0
  7500  16.0  60.8  165   6  3   5.9   3.3 |  17.0  62.6  195   7  3   9.8   5.4
  7250  16.5  61.7  165   7  4   5.6   3.1 |  17.7  63.9  195   7  3  10.4   5.7
  7000  16.9  62.4  160   8  4   5.3   2.9 |  18.5  65.3  195   7  3  10.0   5.5
  6750  17.2  63.0  160   9  5   3.1   1.7 |  19.2  66.6  195   6  3  10.2   5.6
  6500  17.3  63.1  155   9  4   1.0   0.6 |  20.0  68.0  195   6  3  10.8   5.9
  6250  17.4  63.3  145   8  4   0.9   0.5 |  20.8  69.4  200   6  3  11.2   6.1
  6000  17.4  63.3  135   7  4   0.1   0.1 |  21.6  70.9  200   6  3  10.1   5.5
  5750  17.4  63.3  115   6  3   3.1   1.7 |  22.4  72.3  200   6  3  11.5   6.3
  5500  17.7  63.9  115   5  3   6.8   3.7 |  23.3  73.9  200   6  3  14.1   7.7
  5250  18.1  64.6  110   5  3   4.0   2.2 |  24.3  75.7  200   6  3  12.1   6.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/25/2014 at 1500 MDT          |       08/25/2014 at 1800 MDT
                                           |
K index... +32.0  LI... -2.9               | K index... +30.7  LI... -3.4
CAPE... +741.3  CIN... -22.9               | CAPE... +703.5  CIN... -17.5
                                           |
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 -61.9 -79.4  240  46 24   0.4   0.2 | -62.5 -80.5  245  41 21   0.2   0.1
 45000 -60.4 -76.7  245  71 37   2.8   1.5 | -61.2 -78.2  245  65 33   3.0   1.7
 40000 -55.6 -68.1  245  75 39   6.6   3.6 | -55.9 -68.6  245  77 40   7.7   4.2
 38000 -51.7 -61.1  245  68 35   6.4   3.5 | -51.4 -60.5  245  69 35   7.5   4.1
 36000 -47.9 -54.2  245  62 32   6.4   3.5 | -46.9 -52.4  245  60 31   7.5   4.1
 34000 -43.5 -46.3  240  54 28   7.7   4.2 | -42.5 -44.5  240  52 27   7.2   4.0
 32000 -38.8 -37.8  240  47 24   7.8   4.3 | -38.2 -36.8  240  43 22   7.3   4.0
 30000 -34.1 -29.4  240  40 21   8.0   4.4 | -33.5 -28.3  240  36 19   8.1   4.4
 29000 -31.7 -25.1  240  37 19   8.1   4.4 | -31.1 -24.0  240  34 17   8.1   4.4
 28000 -29.3 -20.7  240  34 17   8.1   4.4 | -28.7 -19.7  240  31 16   8.1   4.4
 27000 -27.1 -16.8  240  32 16   7.3   4.0 | -25.9 -14.6  240  29 15   7.6   4.2
 26000 -24.4 -11.9  235  30 15   7.3   4.0 | -23.6 -10.5  235  27 14   7.6   4.2
 25000 -22.3  -8.1  235  29 15   7.3   4.0 | -21.4  -6.5  230  26 13   7.6   4.2
 24000 -20.0  -4.0  235  28 15   7.5   4.1 | -19.3  -2.7  230  25 13   7.2   3.9
 23000 -17.8  -0.0  235  29 15   7.6   4.1 | -17.1   1.2  230  25 13   7.2   4.0
 22000 -15.6   3.9  235  29 15   7.5   4.1 | -15.0   5.0  230  24 13   7.1   3.9
 21000 -13.4   7.9  235  28 14   7.5   4.1 | -13.0   8.6  230  24 12   6.8   3.7
 20000 -11.2  11.8  235  27 14   7.5   4.1 | -11.0  12.2  230  24 12   6.8   3.7
 19500 -10.0  14.0  235  26 14   7.5   4.1 | -10.0  14.0  230  24 12   6.7   3.7
 19000  -9.0  15.8  235  26 14   7.3   4.0 |  -9.0  15.8  230  23 12   7.4   4.0
 18500  -7.9  17.8  235  27 14   7.3   4.0 |  -7.9  17.8  225  22 12   7.4   4.0
 18000  -6.8  19.8  235  27 14   7.3   4.0 |  -6.9  19.6  225  22 11   7.3   4.0
 17500  -5.8  21.6  235  27 14   7.2   3.9 |  -5.8  21.6  220  21 11   7.1   3.9
 17000  -4.8  23.4  235  27 14   7.2   4.0 |  -4.8  23.4  220  21 11   7.1   3.9
 16500  -3.8  25.2  230  26 13   6.7   3.7 |  -3.8  25.2  220  21 11   7.0   3.8
 16000  -2.8  27.0  225  25 13   6.7   3.7 |  -2.8  27.0  215  21 11   7.0   3.8
 15500  -1.9  28.6  225  24 12   7.0   3.8 |  -1.8  28.8  215  21 11   7.3   4.0
 15000  -0.9  30.4  220  23 12   7.1   3.9 |  -0.7  30.7  210  20 11   7.5   4.1
 14500   0.1  32.2  215  22 11   7.3   4.0 |   0.4  32.7  210  20 10   7.6   4.2
 14000   1.2  34.2  210  21 11   8.0   4.4 |   1.5  34.7  210  20 10   8.0   4.4
 13500   2.3  36.1  210  20 10   8.0   4.4 |   2.7  36.9  205  19 10   8.0   4.4
 13000   4.2  39.6  205  18  9   9.0   5.0 |   4.6  40.3  205  18  9   9.3   5.1
 12500   5.5  41.9  200  17  9   9.2   5.1 |   5.9  42.6  205  17  9   9.5   5.2
 12000   6.8  44.2  200  16  8   9.4   5.1 |   7.3  45.1  205  17  9   9.7   5.3
 11500   8.2  46.8  200  16  8   9.3   5.1 |   8.8  47.8  205  16  8   9.6   5.3
 11000   9.5  49.1  195  14  7   9.0   4.9 |  10.2  50.4  205  16  8   9.3   5.1
 10500  10.9  51.6  195  13  6   4.8   2.6 |  11.6  52.9  205  15  8   6.5   3.6
 10250  11.1  52.0  195  12  6   4.9   2.7 |  11.9  53.4  205  15  8   7.2   4.0
 10000  11.7  53.1  195  11  5  10.5   5.8 |  12.7  54.9  205  15  8  11.5   6.3
  9750  12.4  54.3  190   9  5   9.6   5.3 |  13.5  56.3  205  14  7  10.7   5.9
  9500  13.1  55.6  190   8  4   7.6   4.2 |  14.3  57.7  205  14  7   9.7   5.3
  9250  13.6  56.5  195   7  4   6.5   3.6 |  14.9  58.8  205  13  7   8.5   4.6
  9000  14.2  57.6  195   7  3   9.0   4.9 |  15.6  60.1  205  12  6   9.0   4.9
  8750  14.8  58.6  195   6  3   9.0   5.0 |  16.2  61.2  205  11  6   9.2   5.0
  8500  15.5  59.9  200   6  3   9.0   4.9 |  16.9  62.4  205  10  5   8.5   4.7
  8250  16.1  61.0  200   5  3   9.0   5.0 |  17.4  63.3  210   8  4   7.6   4.2
  8000  16.8  62.2  205   5  3   9.5   5.2 |  18.0  64.4  210   7  4   7.3   4.0
  7750  17.5  63.5  210   5  3   9.8   5.4 |  18.5  65.3  215   6  3   6.8   3.7
  7500  18.3  64.9  210   5  2  10.1   5.5 |  19.0  66.2  225   5  3   8.4   4.6
  7250  19.0  66.2  215   5  2  10.7   5.9 |  19.7  67.5  230   5  3   9.7   5.3
  7000  19.8  67.6  215   5  2   9.6   5.3 |  20.3  68.5  235   5  3   9.1   5.0
  6750  20.5  68.9  215   5  2   9.2   5.1 |  21.0  69.8  235   5  2   9.3   5.1
  6500  21.2  70.2  220   5  2  10.5   5.8 |  21.7  71.1  240   5  2  10.0   5.5
  6250  22.0  71.6  220   5  2  11.2   6.1 |  22.5  72.5  240   5  2  10.5   5.8
  6000  22.8  73.0  225   5  2  10.0   5.5 |  23.2  73.8  240   5  2   9.6   5.3
  5750  23.6  74.5  225   4  2  11.0   6.0 |  23.9  75.0  245   4  2   8.6   4.7
  5500  24.5  76.1  230   4  2  13.2   7.2 |  24.6  76.3  245   5  2   8.9   4.9
  5250  25.4  77.7  230   4  2  11.4   6.3 |  25.2  77.4  245   5  2   8.9   4.9
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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