Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 171247
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0647 MDT Wednesday, May 17, 2017

This forecast is for Wednesday, May 17, 2017:

If the trigger temperature of 59.7 F/15.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 4839 ft MSL (0 ft AGL)

Forecast maximum temperature................... 52.0 F/11.6 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Thursday 05/18..... Fair

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

Remarks...

Sunrise/Sunset.................... 05:59:16 / 20:21:40 MDT
Total possible sunshine........... 14 hr 22 min 23 sec (862 min 23 sec)
Altitude of sun at 13:10:39 MDT... 70.37 degrees

Upper air data from rawinsonde observation taken on 05/17/2017 at 0600 MDT

Freezing level.................. 10056 ft MSL (5217 ft AGL)
Convective condensation level... 15588 ft MSL (10749 ft AGL)
Lifted condensation level....... 12953 ft MSL (8114 ft AGL)
Lifted index.................... +9.7
K index......................... +12.8

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  -52.7 -62.9   240   31   16 -11.5  -6.3  114.3 237.7    58.7      M    M
 45000  -52.5 -62.5   250   42   21 -10.2  -5.6   88.5 191.3    47.2      M    M
 40000  -59.2 -74.6   250   43   22  -0.2  -0.1   54.9 130.7    28.5      M    M
 38000  -58.7 -73.7   265   37   19  -1.8  -1.0   46.9 116.3    24.0      M    M
 36000  -56.2 -69.2   280   54   28  -7.2  -4.0   41.9 107.4    21.2      M    M
 34000  -54.1 -65.4   285   62   32   7.1   3.9   36.4  97.6    17.9      M    M
 32000  -48.3 -54.9   280   59   30   7.1   3.9   35.4  95.6    17.7      M    M
 30000  -44.6 -48.3   275   47   24   6.1   3.4   32.5  90.5    16.0      M    M
 29000  -41.9 -43.4   260   39   20   9.0   4.9   32.3  90.1    16.0      M    M
 28000  -39.2 -38.6   265   40   20   8.9   4.9   31.9  89.4    15.9      M    M
 27000  -36.7 -34.1   265   40   21   6.8   3.7   31.4  88.5    15.7      M    M
 26000  -34.3 -29.7   270   41   21   8.7   4.8   30.7  87.3    15.4      M    M
 25000  -31.7 -25.1   270   42   22   8.6   4.7   30.3  86.6    15.3      M    M
 24000  -29.4 -20.9   270   38   19   6.3   3.5   29.5  85.1    14.8      M    M
 23000  -27.2 -17.0   275   34   18   8.0   4.4   28.6  83.5    14.2      M    M
 22000  -24.8 -12.6   280   32   17   7.7   4.2   28.1  82.5    13.9      M    M
 21000  -22.8  -9.0   280   34   18   7.6   4.2   27.0  80.6    13.1      M    M
 20000  -20.7  -5.3   275   37   19   6.3   3.5   26.1  78.9    12.5      M    M
 19500  -19.8  -3.6   270   37   19   4.0   2.2   25.4  77.7    11.9      M    M
 19000  -19.3  -2.7   265   36   19   5.8   3.2   24.4  75.8    11.1      M    M
 18500  -18.4  -1.1   265   36   19   6.3   3.4   23.8  74.8    10.6      M    M
 18000  -17.5   0.5   260   35   18  -0.8  -0.4   22.2  71.9     9.4      M    M
 17500  -17.5   0.5   250   33   17   3.0   1.7   20.5  68.8     8.0      M    M
 17000  -16.4   2.5   235   31   16   8.8   4.8   20.0  68.0     7.6      M    M
 16500  -16.3   2.7   225   31   16   0.7   0.4   18.6  65.4     6.3      M    M
 16000  -15.1   4.8   215   32   16   8.2   4.5   18.3  65.0     6.1      M    M
 15500  -13.8   7.2   215   30   15   8.6   4.7   18.1  64.7     6.0      M    M
 15000  -12.5   9.5   215   28   15   8.7   4.8   18.0  64.3     5.9      M    M
 14500  -11.2  11.8   215   27   14   8.7   4.8   17.8  64.0     5.7      M    M
 14000   -9.9  14.2   215   25   13   8.7   4.8   17.7  63.8     5.6      M    M
 13500   -8.6  16.5   215   24   12   8.7   4.8   17.4  63.4     5.5      M    M
 13000   -7.3  18.9   220   22   11   8.7   4.8   17.2  63.0     5.3      M    M
 12500   -6.0  21.2   220   21   11   8.1   4.5   17.0  62.7     5.2      M    M
 12000   -4.9  23.2   225   20   10   8.0   4.4   16.8  62.2     4.9      M    M
 11500   -3.7  25.3   230   17    9   8.2   4.5   16.5  61.7     4.6      M    M
 11000   -2.4  27.7   240   14    7   8.2   4.5   16.2  61.2     4.4      M    M
 10500   -1.2  29.8   240   15    8   8.4   4.6   16.0  60.8     4.2      M    M
 10250   -0.6  30.9   240   15    8   9.1   5.0   15.9  60.6     4.1      M    M
 10000    0.1  32.2   240   16    8   9.3   5.1   15.9  60.6     4.1      M    M
  9750    0.8  33.4   240   16    8   9.4   5.1   15.8  60.5     4.1      M    M
  9500    1.5  34.7   240   17    9   9.5   5.2   15.8  60.5     4.1      M    M
  9250    2.2  36.0   245   18    9   9.4   5.2   15.8  60.4     4.1      M    M
  9000    2.9  37.2   245   19   10   9.5   5.2   15.8  60.4     4.1      M    M
  8750    3.7  38.7   240   19   10   9.4   5.2   15.8  60.4     4.1      M    M
  8500    4.4  39.9   240   20   10   9.4   5.2   15.8  60.4     4.1      M    M
  8250    5.1  41.2   235   20   10   9.5   5.2   15.7  60.3     4.1      M    M
  8000    5.8  42.4   230   21   11   9.4   5.2   15.7  60.3     4.1      M    M
  7750    6.5  43.7   230   21   11   9.4   5.2   15.7  60.3     4.0      M    M
  7500    7.2  45.0   225   21   11   9.4   5.2   15.7  60.2     4.0      M    M
  7250    7.9  46.2   225   21   11   9.4   5.2   15.6  60.2     4.0      M    M
  7000    8.6  47.5   220   21   11   9.5   5.2   15.6  60.1     4.0      M    M
  6750    9.3  48.7   220   20   10   9.4   5.2   15.6  60.1     4.0      M    M
  6500   10.0  50.0   215   18    9   9.5   5.2   15.6  60.0     3.9      M    M
  6250   10.7  51.3   215   17    9   9.3   5.1   15.5  60.0     3.9      M    M
  6000   11.3  52.3   210   15    8   7.3   4.0   15.4  59.8     3.8      M    M
  5750   11.8  53.2   205   13    6   6.1   3.4   15.2  59.3     3.6      M    M
  5500   12.3  54.1   200    9    5   6.4   3.5   14.9  58.8     3.3      M    M
  5250   12.8  55.0   190    6    3   6.6   3.6   14.7  58.4     3.1      M    M
  5000   13.1  55.6   160    4    2   2.0   1.1   14.3  57.8     2.8      M    M

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

           05/17/2017 at 0900 MDT          |       05/17/2017 at 1200 MDT
                                           |
K index... +23.4  LI... 0.0                | K index... +23.1  LI... +2.2
CAPE... +1.8  CIN... -19.8                 | CAPE... 0.0  CIN... 0.0
                                           |
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 -54.6 -66.3  240  18  9   0.4   0.2 | -54.9 -66.8  230  21 11  -0.2  -0.1
 45000 -54.1 -65.4  260  28 14   0.3   0.2 | -55.2 -67.4  240  26 13  -0.1  -0.0
 40000 -54.0 -65.2  260  45 23   0.1   0.0 | -52.3 -62.1  260  41 21   2.0   1.1
 38000 -53.9 -65.0  260  51 27   0.1   0.1 | -51.8 -61.2  260  51 26  -1.3  -0.7
 36000 -53.8 -64.8  260  58 30   0.1   0.1 | -52.5 -62.5  260  63 32  -1.3  -0.7
 34000 -53.3 -63.9  260  65 34   7.8   4.3 | -53.1 -63.6  255  74 38   4.1   2.2
 32000 -48.6 -55.5  265  63 32   7.8   4.3 | -49.0 -56.2  255  73 37   6.9   3.8
 30000 -43.9 -47.0  270  60 31   7.5   4.1 | -44.9 -48.8  255  71 36   7.4   4.1
 29000 -41.7 -43.1  270  56 29   7.3   4.0 | -42.7 -44.9  255  69 36   7.4   4.1
 28000 -39.5 -39.1  270  52 27   7.3   4.0 | -40.5 -40.9  255  67 35   7.4   4.1
 27000 -37.3 -35.1  270  48 25   7.2   4.0 | -38.3 -36.9  255  65 34   7.4   4.1
 26000 -34.9 -30.8  265  46 24   8.2   4.5 | -35.5 -31.9  250  61 32   7.2   3.9
 25000 -32.4 -26.3  260  45 23   8.3   4.5 | -33.4 -28.1  245  58 30   7.2   4.0
 24000 -30.0 -22.0  260  45 23   8.4   4.6 | -31.3 -24.3  240  55 28   7.1   3.9
 23000 -27.9 -18.2  260  44 22   6.1   3.4 | -28.8 -19.8  240  52 27   8.8   4.8
 22000 -26.1 -15.0  260  42 22   6.1   3.3 | -26.2 -15.2  235  49 25   8.8   4.8
 21000 -24.3 -11.7  265  41 21   6.1   3.3 | -23.6 -10.5  235  46 24   8.5   4.7
 20000 -22.4  -8.3  265  38 20   6.4   3.5 | -21.5  -6.7  230  43 22   6.9   3.8
 19500 -21.4  -6.5  260  36 19   6.4   3.5 | -20.4  -4.7  230  42 22   7.0   3.8
 19000 -20.5  -4.9  260  35 18   6.4   3.5 | -19.4  -2.9  230  41 21   7.0   3.8
 18500 -19.6  -3.3  255  33 17   6.4   3.5 | -18.4  -1.1  230  40 20   7.0   3.8
 18000 -18.6  -1.5  255  32 16   7.2   3.9 | -17.4   0.7  225  38 20   7.1   3.9
 17500 -17.5   0.5  250  32 16   7.2   4.0 | -16.3   2.7  225  37 19   7.1   3.9
 17000 -16.5   2.3  250  31 16   7.7   4.2 | -15.3   4.5  225  36 19   6.3   3.5
 16500 -15.2   4.6  250  31 16   8.4   4.6 | -14.4   6.1  225  35 18   5.9   3.2
 16000 -14.0   6.8  245  30 15   8.4   4.6 | -13.6   7.5  225  35 18   5.9   3.3
 15500 -12.2  10.0  245  29 15   7.9   4.3 | -12.7   9.1  225  33 17   6.7   3.7
 15000 -11.1  12.0  245  29 15   7.6   4.2 | -11.7  10.9  225  32 16   6.7   3.7
 14500 -10.1  13.8  245  28 14   6.9   3.8 | -10.8  12.6  225  30 16   5.8   3.2
 14000  -9.1  15.6  250  27 14   6.9   3.8 |  -9.9  14.2  225  28 14   5.8   3.2
 13500  -8.1  17.4  250  26 13   6.4   3.5 |  -9.1  15.6  225  26 13   5.7   3.2
 13000  -7.1  19.2  250  25 13   6.5   3.6 |  -7.8  18.0  230  23 12   5.7   3.2
 12500  -6.3  20.7  250  24 12   5.8   3.2 |  -7.0  19.4  230  21 11   5.9   3.2
 12000  -5.4  22.3  250  23 12   6.0   3.3 |  -6.2  20.8  235  20 10   5.9   3.2
 11500  -4.6  23.7  250  23 12   4.8   2.6 |  -5.3  22.5  235  19 10   5.7   3.1
 11000  -3.9  25.0  250  24 12   4.9   2.7 |  -4.5  23.9  235  18  9   5.8   3.2
 10500  -3.2  26.2  250  24 12   5.3   2.9 |  -3.7  25.3  235  16  8   5.2   2.9
 10250  -2.8  27.0  255  24 12   5.2   2.9 |  -3.3  26.1  230  15  8   5.2   2.9
 10000  -2.4  27.7  255  24 12   5.3   2.9 |  -3.0  26.6  230  15  7   5.0   2.8
  9750  -2.0  28.4  255  24 12   5.0   2.8 |  -2.6  27.3  225  14  7   5.0   2.7
  9500  -1.7  28.9  250  24 12   4.8   2.6 |  -2.2  28.0  225  14  7   4.9   2.7
  9250  -1.3  29.7  250  24 12   4.9   2.7 |  -1.9  28.6  220  13  7   5.1   2.8
  9000  -1.0  30.2  245  24 12   4.6   2.5 |  -1.5  29.3  215  13  7   4.7   2.6
  8750  -0.6  30.9  245  24 12   5.0   2.7 |  -1.2  29.8  215  13  7   3.7   2.0
  8500  -0.2  31.6  240  23 12   5.7   3.1 |  -1.0  30.2  210  13  7   3.5   1.9
  8250   0.2  32.4  240  22 11   5.3   2.9 |  -0.7  30.7  205  13  7   3.2   1.7
  8000   0.6  33.1  235  21 11   6.1   3.4 |  -0.5  31.1  200  13  7   5.1   2.8
  7750   1.1  34.0  235  19 10   5.0   2.7 |  -0.0  32.0  195  12  6   6.0   3.3
  7500   1.3  34.3  230  17  9   3.2   1.7 |   0.3  32.5  195  12  6   4.4   2.4
  7250   1.6  34.9  225  15  8   4.3   2.4 |   0.7  33.3  190  12  6   5.9   3.2
  7000   2.0  35.6  225  14  7   7.1   3.9 |   1.2  34.2  190  11  6   8.7   4.8
  6750   2.7  36.9  220  13  7   8.8   4.8 |   1.9  35.4  185  11  6   9.4   5.2
  6500   3.3  37.9  220  12  6   8.3   4.6 |   2.6  36.7  185  10  5   8.9   4.9
  6250   3.9  39.0  220  11  6   9.3   5.1 |   3.2  37.8  185  10  5   9.4   5.2
  6000   4.7  40.5  215  10  5  10.1   5.5 |   3.9  39.0  185   9  5   9.7   5.3
  5750   5.4  41.7  215   9  5   9.8   5.4 |   4.6  40.3  185   9  5   9.4   5.1
  5500   6.1  43.0  210   8  4   9.0   5.0 |   5.3  41.5  180   8  4   9.4   5.2
  5250   6.7  44.1  215   8  4   7.1   3.9 |   6.0  42.8  185   8  4   9.8   5.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/17/2017 at 1500 MDT          |       05/17/2017 at 1800 MDT
                                           |
K index... +21.3  LI... +4.0               | K index... +15.6  LI... +6.1
CAPE... +18.1  CIN... 0.0                  | CAPE... 0.0  CIN... 0.0
                                           |
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 -54.2 -65.6  240  26 13   0.8   0.4 | -53.6 -64.5  245  26 13   0.7   0.4
 45000 -53.0 -63.4  245  37 19   0.8   0.4 | -52.5 -62.5  255  37 19   0.7   0.4
 40000 -51.2 -60.2  245  42 22   1.1   0.6 | -50.3 -58.5  245  47 24   1.4   0.8
 38000 -50.9 -59.6  250  48 25  -0.3  -0.2 | -50.2 -58.4  245  53 27  -1.5  -0.8
 36000 -51.1 -60.0  250  58 30  -0.3  -0.2 | -51.1 -60.0  245  63 32  -1.5  -0.8
 34000 -51.3 -60.3  255  68 35   2.1   1.1 | -52.0 -61.6  245  72 37   0.6   0.3
 32000 -48.5 -55.3  250  70 36   4.6   2.5 | -49.7 -57.5  230  71 36   4.0   2.2
 30000 -45.7 -50.3  245  71 37   6.4   3.5 | -47.3 -53.1  220  72 37   7.0   3.8
 29000 -43.4 -46.1  245  69 36   7.8   4.3 | -44.4 -47.9  220  68 35   9.7   5.3
 28000 -41.1 -42.0  245  68 35   7.8   4.3 | -40.8 -41.4  215  64 33   9.7   5.3
 27000 -38.2 -36.8  245  66 34   7.9   4.3 | -37.9 -36.2  215  60 31   9.8   5.4
 26000 -36.1 -33.0  245  64 33   6.6   3.6 | -35.5 -31.9  215  57 29   7.6   4.2
 25000 -34.2 -29.6  245  63 32   6.6   3.6 | -33.2 -27.8  215  54 28   7.7   4.2
 24000 -32.2 -26.0  245  61 32   6.5   3.5 | -30.9 -23.6  220  51 26   7.7   4.2
 23000 -29.8 -21.6  240  60 31   8.9   4.9 | -28.7 -19.7  220  48 24   7.1   3.9
 22000 -27.1 -16.8  240  58 30   9.0   4.9 | -26.6 -15.9  225  44 23   7.1   3.9
 21000 -24.5 -12.1  235  56 29   9.0   4.9 | -24.5 -12.1  230  40 21   7.2   3.9
 20000 -21.9  -7.4  235  55 29   8.6   4.7 | -22.0  -7.6  230  38 20   8.6   4.7
 19500 -20.7  -5.3  235  55 29   8.6   4.7 | -20.8  -5.4  225  38 19   8.6   4.7
 19000 -19.4  -2.9  235  55 29   8.6   4.7 | -19.5  -3.1  225  37 19   8.6   4.7
 18500 -18.1  -0.6  235  55 29   8.8   4.8 | -18.2  -0.8  225  36 18   8.8   4.8
 18000 -17.0   1.4  235  55 28   7.0   3.8 | -17.0   1.4  225  36 18   7.4   4.1
 17500 -15.9   3.4  235  52 27   7.1   3.9 | -15.9   3.4  220  36 19   7.5   4.1
 17000 -14.9   5.2  235  50 26   6.5   3.5 | -14.8   5.4  220  37 19   6.8   3.7
 16500 -14.0   6.8  230  47 24   5.8   3.2 | -14.0   6.8  215  37 19   5.9   3.3
 16000 -13.2   8.2  230  44 23   5.7   3.1 | -13.1   8.4  215  38 19   5.9   3.2
 15500 -12.5   9.5  230  41 21   3.8   2.1 | -12.3   9.9  210  37 19   5.6   3.1
 15000 -11.9  10.6  230  38 19   3.9   2.1 | -11.5  11.3  210  36 19   5.7   3.1
 14500 -11.3  11.7  225  34 18   4.4   2.4 | -10.7  12.7  210  35 18   4.8   2.6
 14000 -10.7  12.7  225  31 16   4.3   2.4 | -10.0  14.0  210  32 16   4.8   2.6
 13500 -10.0  14.0  225  28 14   5.2   2.9 |  -9.1  15.6  215  26 13   2.9   1.6
 13000  -8.8  16.2  225  23 12   5.5   3.0 |  -8.7  16.3  215  20 10   3.2   1.7
 12500  -8.0  17.6  230  21 11   5.1   2.8 |  -8.4  16.9  225  14  7   1.0   0.6
 12000  -7.3  18.9  230  18  9   5.1   2.8 |  -8.2  17.2  240   9  5   1.0   0.5
 11500  -6.5  20.3  230  16  8   5.8   3.2 |  -7.8  18.0  270   7  3   3.5   1.9
 11000  -5.7  21.7  235  14  7   5.8   3.2 |  -7.4  18.7  295   6  3   3.2   1.8
 10500  -4.9  23.2  240  13  7   4.9   2.7 |  -6.8  19.8  325   6  3   4.7   2.6
 10250  -4.5  23.9  240  13  6   5.4   3.0 |  -6.4  20.5  335   7  4   4.5   2.5
 10000  -4.1  24.6  240  12  6   6.4   3.5 |  -6.1  21.0  345   8  4   5.5   3.0
  9750  -3.7  25.3  245  12  6   5.4   3.0 |  -5.7  21.7  350   8  4   6.1   3.4
  9500  -3.3  26.1  250  11  6   4.3   2.4 |  -5.2  22.6  355  10  5   5.9   3.2
  9250  -3.0  26.6  255  11  5   4.4   2.4 |  -4.8  23.4  360  11  5   6.0   3.3
  9000  -2.7  27.1  260  10  5   5.0   2.8 |  -4.4  24.1  360  12  6   5.9   3.3
  8750  -2.3  27.9  265  10  5   5.2   2.9 |  -4.0  24.8  005  13  7   5.2   2.9
  8500  -1.9  28.6  270   9  5   4.7   2.6 |  -3.6  25.5  005  14  7   4.8   2.6
  8250  -1.6  29.1  275   9  5   4.7   2.6 |  -3.3  26.1  005  15  8   4.8   2.6
  8000  -1.3  29.7  285   9  4   5.2   2.9 |  -2.9  26.8  005  16  8   5.3   2.9
  7750  -0.9  30.4  290   8  4   5.6   3.1 |  -2.5  27.5  360  16  8   5.3   2.9
  7500  -0.5  31.1  295   8  4   5.2   2.8 |  -2.2  28.0  360  16  8   4.4   2.4
  7250  -0.1  31.8  300   8  4   6.0   3.3 |  -1.8  28.8  355  16  8   5.4   3.0
  7000   0.4  32.7  305   8  4   8.2   4.5 |  -1.4  29.5  355  15  8   6.7   3.7
  6750   1.1  34.0  305   8  4   9.4   5.2 |  -0.9  30.4  345  14  7   5.5   3.0
  6500   1.7  35.1  310   7  4   9.2   5.1 |  -0.6  30.9  340  13  7   4.5   2.5
  6250   2.4  36.3  310   7  4   9.9   5.5 |  -0.2  31.6  330  12  6   5.1   2.8
  6000   3.1  37.6  310   7  4  10.4   5.7 |   0.2  32.4  325  11  5   5.6   3.1
  5750   3.8  38.8  310   7  4   9.3   5.1 |   0.6  33.1  320   9  5   6.0   3.3
  5500   4.5  40.1  310   6  3   9.5   5.2 |   1.1  34.0  320   8  4   7.3   4.0
  5250   5.3  41.5  310   6  3  11.4   6.2 |   1.6  34.9  320   8  4   8.8   4.8
  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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