Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 191239
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0539 MST Friday, January 19, 2018

This forecast is for Friday, January 19, 2018:

If the trigger temperature of 58.5 F/14.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7242 ft MSL (2403 ft AGL)

Forecast maximum temperature................... 51.0 F/11.0 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1700 MST
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................. 6548 ft MSL (1709 ft AGL)
Thermal soaring outlook for Saturday 01/20..... Fair

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

Remarks...

Sunrise/Sunset.................... 07:29:46 / 17:19:11 MST
Total possible sunshine........... 9 hr 49 min 25 sec (589 min 25 sec)
Altitude of sun at 12:24:52 MST... 30.72 degrees

Upper air data from rawinsonde observation taken on 01/19/2018 at 0500 MST

Freezing level.................. 5102 ft MSL (263 ft AGL)
Additional freezing level....... 11365 ft MSL (6526 ft AGL)
Convective condensation level... 20113 ft MSL (15274 ft AGL)
Lifted condensation level....... 13282 ft MSL (8443 ft AGL)
Lifted index.................... +13.3
K index......................... -1.0

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  -62.7 -80.9   280   27   14   5.7   3.1   97.6 207.6    49.4      M    M
 45000  -73.2 -99.8   265   33   17  -2.8  -1.5   55.0 131.0    27.1      M    M
 40000  -62.7 -80.9   260   34   17   6.7   3.6   48.2 118.8    24.7      M    M
 38000  -59.2 -74.6   265   48   25   5.4   3.0   44.8 112.6    23.1      M    M
 36000  -54.3 -65.7   265   56   29   7.9   4.3   43.4 110.0    22.7      M    M
 34000  -49.2 -56.6   260   51   26   9.2   5.0   41.2 106.2    21.9      M    M
 32000  -44.0 -47.2   255   50   26   8.8   4.8   40.3 104.6    21.8      M    M
 30000  -40.0 -40.0   255   50   26   8.5   4.7   37.9 100.2    20.5      M    M
 29000  -37.3 -35.1   255   49   25   9.3   5.1   37.5  99.5    20.4      M    M
 28000  -34.6 -30.3   255   49   25   9.0   5.0   37.2  98.9    20.5      M    M
 27000  -32.4 -26.3   255   48   25   6.6   3.6   36.3  97.4    20.0      M    M
 26000  -29.8 -21.6   255   48   25   8.2   4.5   35.9  96.7    19.9      M    M
 25000  -27.7 -17.9   255   47   24   7.0   3.9   34.9  94.7    19.3      M    M
 24000  -26.1 -15.0   265   51   26   1.2   0.7   33.2  91.8    18.2      M    M
 23000  -24.4 -11.9   265   49   25   7.4   4.1   31.7  89.0    17.2      M    M
 22000  -22.6  -8.7   265   46   24   7.7   4.2   30.4  86.7    16.3      M    M
 21000  -20.2  -4.4   260   44   23   8.2   4.5   29.8  85.6    15.9      M    M
 20000  -17.7   0.1   260   42   22   8.2   4.5   29.3  84.7    15.7      M    M
 19500  -16.5   2.3   260   42   22   8.3   4.5   29.0  84.2    15.6      M    M
 19000  -14.8   5.4   255   43   22   7.3   4.0   28.4  83.1    15.1      M    M
 18500  -13.7   7.3   255   42   22   7.6   4.2   28.0  82.4    14.9      M    M
 18000  -12.6   9.3   255   41   21   7.5   4.1   27.6  81.7    14.6      M    M
 17500  -11.5  11.3   255   40   21   6.9   3.8   27.2  81.0    14.4      M    M
 17000  -10.5  13.1   250   39   20   6.3   3.5   26.7  80.0    13.9      M    M
 16500   -9.5  14.9   250   38   20   8.0   4.4   26.2  79.1    13.5      M    M
 16000   -8.2  17.2   250   37   19   8.9   4.9   26.0  78.8    13.5      M    M
 15500   -6.9  19.6   250   38   19   8.9   4.9   25.8  78.5    13.4      M    M
 15000   -5.5  22.1   250   39   20   8.9   4.9   25.7  78.2    13.3      M    M
 14500   -4.2  24.4   250   39   20   8.7   4.8   25.5  78.0    13.3      M    M
 14000   -2.9  26.8   250   40   20   4.1   2.2   25.4  77.7    13.2      M    M
 13500   -2.9  26.8   250   36   19   0.3   0.2   23.8  74.8    11.8      M    M
 13000   -2.7  27.1   250   33   17   5.1   2.8   22.5  72.5    10.6      M    M
 12500   -1.7  28.9   245   29   15   5.8   3.2   21.9  71.5    10.2      M    M
 12000   -1.0  30.2   245   26   13   5.4   3.0   21.2  70.2     9.6      M    M
 11500   -0.2  31.6   250   26   13   5.5   3.0   20.5  68.9     8.9      M    M
 11000    0.6  33.1   255   26   13   6.7   3.7   19.8  67.7     8.3      M    M
 10500    0.7  33.3   245   26   13  -8.3  -4.6   18.5  65.2     7.0      M    M
 10250    0.3  32.5   240   27   14  -0.8  -0.4   17.1  62.8     5.8      M    M
 10000    0.7  33.3   235   26   14   7.2   3.9   16.8  62.2     5.5      M    M
  9750    1.1  34.0   235   23   12   4.7   2.6   16.4  61.6     5.2      M    M
  9500    1.5  34.7   235   20   10   5.4   3.0   16.1  60.9     4.9      M    M
  9250    1.9  35.4   230   17    9   5.2   2.9   15.7  60.3     4.6      M    M
  9000    2.3  36.1   230   14    7   5.2   2.9   15.4  59.7     4.3      M    M
  8750    2.7  36.9   220   13    6   5.3   2.9   15.0  59.0     3.9      M    M
  8500    3.1  37.6   205   12    6   5.2   2.8   14.7  58.4     3.6      M    M
  8250    3.5  38.3   190   11    6   5.5   3.0   14.3  57.8     3.3      M    M
  8000    3.9  39.0   175   12    6   4.3   2.3   14.0  57.2     3.0      M    M
  7750    4.3  39.7   175   13    7   8.9   4.9   13.6  56.5     2.6      M    M
  7500    4.7  40.5   170   15    8  -8.3  -4.5   13.3  55.9     2.3      M    M
  7250    3.3  37.9   170   17    9 -13.9  -7.6   11.1  52.0     0.2      M    M
  7000    3.2  37.8   170   19   10   5.8   3.2   10.3  50.5    -0.6    194  1.0
  6750    3.3  37.9   165   18    9  -7.8  -4.3    9.7  49.4    -1.2    182  0.9
  6500    2.3  36.1   160   16    8  -8.5  -4.7    7.9  46.2    -3.0    204  1.0
  6250    2.4  36.3   150   14    7   3.7   2.0    7.2  45.0    -3.7    196  1.0
  6000    2.6  36.7   145   13    7   4.0   2.2    6.7  44.0    -4.2    182  0.9
  5750    2.8  37.0   140   12    6  -2.2  -1.2    6.2  43.1    -4.7    169  0.9
  5500    2.1  35.8   135   10    5 -12.0  -6.6    4.8  40.6    -6.1    181  0.9
  5250    1.2  34.2   125    8    4 -14.2  -7.8    3.0  37.5    -7.9    203  1.0
  5000   -0.1  31.8   115    6    3 -19.5 -10.7    1.1  33.9    -9.9    233  1.2

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

           01/19/2018 at 0800 MST          |       01/19/2018 at 1100 MST
                                           |
K index... +7.3  LI... +4.5                | K index... +6.7  LI... +2.9
CAPE... 0.0  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 -65.5 -85.9  265  28 15  -3.0  -1.6 | -64.7 -84.5  270  25 13  -3.0  -1.7
 45000 -70.2 -94.4  255  42 21   0.5   0.3 | -69.2 -92.6  250  38 20  -0.3  -0.2
 40000 -64.0 -83.2  260  59 31   4.1   2.3 | -63.9 -83.0  255  67 34   3.5   1.9
 38000 -59.9 -75.8  260  60 31   8.2   4.5 | -60.1 -76.2  255  69 36   8.2   4.5
 36000 -55.0 -67.0  260  58 30   8.2   4.5 | -55.2 -67.4  255  65 34   8.2   4.5
 34000 -50.1 -58.2  255  56 29   8.1   4.4 | -50.2 -58.4  255  62 32   8.1   4.5
 32000 -44.6 -48.3  255  56 29   8.1   4.4 | -44.7 -48.5  255  61 31   8.1   4.4
 30000 -39.8 -39.6  255  55 28   8.1   4.4 | -39.9 -39.8  250  59 30   7.9   4.3
 29000 -37.3 -35.1  255  53 27   8.1   4.5 | -37.5 -35.5  250  58 30   7.9   4.3
 28000 -34.9 -30.8  250  51 26   8.1   4.5 | -35.2 -31.4  250  56 29   7.9   4.3
 27000 -32.5 -26.5  250  50 26   7.6   4.2 | -32.8 -27.0  245  55 28   7.8   4.3
 26000 -30.2 -22.4  250  48 25   7.7   4.2 | -30.5 -22.9  245  54 28   7.8   4.3
 25000 -27.9 -18.2  255  46 24   7.7   4.2 | -28.1 -18.6  245  53 27   7.8   4.3
 24000 -25.6 -14.1  255  45 23   6.8   3.7 | -25.8 -14.4  245  52 27   6.6   3.6
 23000 -23.7 -10.7  255  46 23   6.5   3.6 | -24.0 -11.2  245  52 27   5.9   3.3
 22000 -21.8  -7.2  255  46 24   6.5   3.6 | -22.3  -8.1  250  51 26   5.9   3.3
 21000 -19.8  -3.6  260  47 24   7.5   4.1 | -20.5  -4.9  250  51 26   6.7   3.7
 20000 -17.6   0.3  260  45 23   7.4   4.1 | -18.5  -1.3  255  50 26   6.8   3.7
 19500 -16.4   2.5  260  45 23   7.4   4.1 | -17.5   0.5  255  50 26   6.8   3.7
 19000 -15.3   4.5  260  44 23   7.5   4.1 | -16.5   2.3  255  50 26   6.8   3.7
 18500 -14.3   6.3  260  43 22   6.9   3.8 | -15.4   4.3  255  49 25   7.5   4.1
 18000 -13.3   8.1  260  43 22   6.7   3.7 | -14.3   6.3  255  49 25   7.7   4.2
 17500 -12.3   9.9  260  42 22   6.7   3.7 | -13.1   8.4  260  49 25   7.8   4.3
 17000 -11.3  11.7  260  43 22   6.7   3.7 | -12.0  10.4  260  49 25   7.9   4.4
 16500 -10.3  13.5  260  43 22   6.7   3.7 | -10.8  12.6  260  48 25   8.0   4.4
 16000  -9.3  15.3  260  43 22   7.0   3.8 |  -9.6  14.7  260  47 24   7.5   4.1
 15500  -8.2  17.2  260  43 22   7.0   3.8 |  -7.9  17.8  260  46 24   7.5   4.1
 15000  -6.7  19.9  260  43 22   7.3   4.0 |  -6.8  19.8  255  45 23   7.0   3.8
 14500  -5.6  21.9  260  43 22   7.3   4.0 |  -5.8  21.6  255  44 23   7.1   3.9
 14000  -4.6  23.7  260  43 22   6.7   3.7 |  -4.8  23.4  255  43 22   6.1   3.3
 13500  -3.6  25.5  260  42 22   6.7   3.7 |  -4.0  24.8  255  42 22   6.0   3.3
 13000  -2.6  27.3  260  41 21   5.8   3.2 |  -3.1  26.4  255  41 21   5.8   3.2
 12500  -1.9  28.6  260  38 20   5.5   3.0 |  -2.3  27.9  255  39 20   5.7   3.1
 12000  -1.1  30.0  255  36 19   4.6   2.5 |  -1.5  29.3  255  38 19   5.2   2.8
 11500  -0.5  31.1  255  34 18   4.1   2.3 |  -0.8  30.6  255  36 19   4.9   2.7
 11000   0.1  32.2  250  33 17   3.5   1.9 |  -0.2  31.6  255  34 18   3.4   1.9
 10500   0.6  33.1  250  32 17   3.0   1.6 |   0.2  32.4  250  33 17   2.3   1.3
 10250   0.8  33.4  245  32 16   4.1   2.2 |   0.4  32.7  250  33 17   4.1   2.2
 10000   1.2  34.2  245  31 16   4.9   2.7 |   0.8  33.4  245  32 16   5.5   3.0
  9750   1.5  34.7  245  29 15   4.3   2.3 |   1.2  34.2  245  30 16   4.5   2.5
  9500   1.9  35.4  240  27 14   4.9   2.7 |   1.6  34.9  245  29 15   5.2   2.8
  9250   2.2  36.0  240  25 13   3.1   1.7 |   2.0  35.6  240  28 14   3.6   2.0
  9000   2.4  36.3  235  23 12   2.0   1.1 |   2.2  36.0  240  26 13   2.7   1.5
  8750   2.6  36.7  235  20 11   3.1   1.7 |   2.4  36.3  235  23 12   3.6   2.0
  8500   2.8  37.0  230  18  9   3.3   1.8 |   2.7  36.9  235  20 10   3.9   2.2
  8250   3.1  37.6  225  16  8   2.5   1.4 |   3.0  37.4  230  18  9   2.4   1.3
  8000   3.2  37.8  220  16  8   1.8   1.0 |   3.1  37.6  225  15  8   1.2   0.7
  7750   3.4  38.1  215  15  8   2.5   1.4 |   3.3  37.9  220  14  7   2.5   1.4
  7500   3.6  38.5  205  16  8   2.5   1.4 |   3.5  38.3  215  13  7   2.6   1.4
  7250   3.7  38.7  200  16  8   2.3   1.3 |   3.6  38.5  210  12  6   2.3   1.2
  7000   3.9  39.0  195  16  8   1.6   0.9 |   3.8  38.8  205  12  6   2.3   1.2
  6750   4.0  39.2  190  16  8   2.1   1.2 |   4.0  39.2  200  11  6   1.0   0.5
  6500   4.1  39.4  180  16  8  -3.5  -1.9 |   4.1  39.4  195  10  5   4.0   2.2
  6250   3.5  38.3  175  14  7  -9.3  -5.1 |   4.6  40.3  190   9  5   7.4   4.1
  6000   2.9  37.2  170  13  7  -6.1  -3.3 |   5.1  41.2  185   8  4   6.8   3.7
  5750   2.4  36.3  155  10  5  -9.1  -5.0 |   5.6  42.1  185   7  4   8.2   4.5
  5500   1.4  34.5  135   8  4 -18.0  -9.9 |   6.3  43.3  185   6  3   9.0   4.9
  5250  -0.1  31.8  125   6  3 -20.6 -11.3 |   6.9  44.4  185   6  3   8.5   4.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/19/2018 at 1400 MST          |       01/19/2018 at 1700 MST
                                           |
K index... +0.9  LI... +3.2                | K index... +6.0  LI... +3.0
CAPE... 0.0  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 -63.0 -81.4  260  19 10  -2.5  -1.4 | -62.3 -80.1  265  26 13  -1.9  -1.0
 45000 -66.8 -88.2  245  29 15  -1.3  -0.7 | -65.2 -85.4  255  43 22  -1.0  -0.5
 40000 -63.8 -82.8  250  67 34   2.0   1.1 | -63.0 -81.4  245  73 37   1.5   0.8
 38000 -60.4 -76.7  250  72 37   8.3   4.6 | -59.9 -75.8  245  77 39   7.9   4.4
 36000 -55.4 -67.7  250  71 36   8.3   4.6 | -55.2 -67.4  245  74 38   7.9   4.4
 34000 -50.5 -58.9  250  69 35   8.1   4.4 | -50.4 -58.7  245  72 37   7.8   4.3
 32000 -45.0 -49.0  250  68 35   8.1   4.4 | -45.7 -50.3  245  72 37   7.8   4.3
 30000 -40.2 -40.4  250  66 34   8.1   4.4 | -40.5 -40.9  250  71 37   7.8   4.3
 29000 -37.8 -36.0  250  65 33   8.0   4.4 | -38.1 -36.6  245  70 36   7.8   4.3
 28000 -35.3 -31.5  250  63 33   8.0   4.4 | -35.8 -32.4  245  69 35   7.8   4.3
 27000 -32.9 -27.2  245  62 32   7.5   4.1 | -33.5 -28.3  245  67 35   6.7   3.7
 26000 -30.7 -23.3  245  62 32   7.4   4.1 | -31.6 -24.9  245  67 34   6.4   3.5
 25000 -28.5 -19.3  245  61 31   7.4   4.1 | -29.7 -21.5  245  66 34   6.4   3.5
 24000 -26.3 -15.3  245  61 31   6.5   3.6 | -27.7 -17.9  245  65 34   6.2   3.4
 23000 -24.6 -12.3  245  59 31   5.4   3.0 | -26.0 -14.8  250  64 33   5.7   3.2
 22000 -23.0  -9.4  250  58 30   5.5   3.0 | -24.3 -11.7  250  62 32   5.8   3.2
 21000 -21.3  -6.3  250  57 29   7.0   3.8 | -22.6  -8.7  250  61 31   7.8   4.3
 20000 -19.2  -2.6  250  56 29   7.4   4.0 | -20.0  -4.0  250  58 30   8.5   4.7
 19500 -18.1  -0.6  250  56 29   7.4   4.0 | -18.7  -1.7  250  56 29   8.5   4.7
 19000 -17.0   1.4  250  55 28   7.4   4.1 | -17.5   0.5  250  54 28   8.5   4.7
 18500 -15.9   3.4  250  54 28   8.0   4.4 | -16.2   2.8  250  53 27   8.4   4.6
 18000 -14.6   5.7  250  54 28   8.5   4.7 | -14.9   5.2  250  54 28   8.2   4.5
 17500 -13.3   8.1  250  53 27   8.6   4.7 | -13.7   7.3  250  56 29   8.3   4.5
 17000 -12.0  10.4  250  52 27   7.7   4.2 | -12.5   9.5  250  56 29   7.6   4.2
 16500 -10.9  12.4  250  52 27   7.8   4.3 | -11.4  11.5  250  56 29   7.7   4.2
 16000  -9.7  14.5  250  51 26   7.4   4.1 | -10.2  13.6  250  55 28   7.4   4.1
 15500  -8.1  17.4  250  50 26   7.3   4.0 |  -9.1  15.6  250  54 28   7.2   4.0
 15000  -7.0  19.4  250  49 25   6.6   3.6 |  -8.0  17.6  250  53 27   7.0   3.8
 14500  -6.1  21.0  250  49 25   6.6   3.6 |  -6.6  20.1  250  51 26   6.5   3.6
 14000  -5.1  22.8  250  48 25   6.2   3.4 |  -5.6  21.9  250  49 25   6.4   3.5
 13500  -4.2  24.4  250  47 24   6.1   3.4 |  -4.7  23.5  250  48 24   6.3   3.4
 13000  -3.4  25.9  250  46 24   5.7   3.1 |  -3.8  25.2  250  46 24   5.9   3.2
 12500  -2.6  27.3  250  44 23   5.3   2.9 |  -3.0  26.6  250  43 22   5.6   3.1
 12000  -1.9  28.6  250  43 22   4.8   2.6 |  -2.3  27.9  250  41 21   5.3   2.9
 11500  -1.3  29.7  250  41 21   4.2   2.3 |  -1.6  29.1  250  38 20   5.0   2.7
 11000  -0.8  30.6  250  39 20   4.0   2.2 |  -0.9  30.4  250  36 19   5.1   2.8
 10500  -0.2  31.6  250  37 19   3.6   2.0 |  -0.1  31.8  245  34 17   5.2   2.8
 10250   0.1  32.2  250  36 19   5.4   2.9 |   0.3  32.5  245  32 17   5.4   3.0
 10000   0.6  33.1  245  35 18   6.3   3.4 |   0.7  33.3  245  31 16   6.3   3.5
  9750   1.0  33.8  245  33 17   5.2   2.9 |   1.2  34.2  240  28 15   6.8   3.7
  9500   1.4  34.5  245  30 16   5.4   3.0 |   1.8  35.2  235  26 13   6.8   3.7
  9250   1.9  35.4  240  28 14   5.6   3.1 |   2.3  36.1  230  24 12   6.4   3.5
  9000   2.3  36.1  235  26 13   5.0   2.7 |   2.7  36.9  225  21 11   5.6   3.1
  8750   2.6  36.7  235  23 12   4.2   2.3 |   3.2  37.8  220  20 10   5.5   3.0
  8500   3.0  37.4  230  20 11   4.6   2.5 |   3.6  38.5  215  19 10   5.4   3.0
  8250   3.3  37.9  220  18  9   3.9   2.1 |   4.0  39.2  210  19 10   5.9   3.3
  8000   3.6  38.5  215  16  8   3.8   2.1 |   4.5  40.1  205  18  9   6.6   3.6
  7750   3.9  39.0  210  13  7   4.9   2.7 |   5.0  41.0  200  17  9   6.4   3.5
  7500   4.3  39.7  205  12  6   5.1   2.8 |   5.4  41.7  195  16  8   6.2   3.4
  7250   4.7  40.5  200  10  5   6.2   3.4 |   5.9  42.6  190  16  8   6.8   3.7
  7000   5.2  41.4  200   8  4   7.5   4.1 |   6.4  43.5  190  14  7   7.1   3.9
  6750   5.8  42.4  200   7  4   7.5   4.1 |   6.9  44.4  190  13  7   6.5   3.6
  6500   6.4  43.5  205   7  3   8.8   4.8 |   7.4  45.3  190  12  6   6.0   3.3
  6250   7.1  44.8  205   6  3  10.4   5.7 |   7.8  46.0  190  10  5   5.2   2.9
  6000   7.9  46.2  205   6  3  10.4   5.7 |   8.2  46.8  190   8  4   4.9   2.7
  5750   8.6  47.5  210   5  3   9.5   5.2 |   8.5  47.3  190   6  3   4.8   2.6
  5500   9.3  48.7  210   5  3   8.7   4.7 |   8.8  47.8  185   3  2  -0.2  -0.1
  5250  10.0  50.0  215   5  3   8.7   4.8 |   8.4  47.1  185   3  2  -8.0  -4.4
  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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