Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 191306
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0605 MST Monday, January 19, 2015

This forecast is for Monday, January 19, 2015:

If the trigger temperature of 53.7 F/12.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6927 ft MSL (2088 ft AGL)

Forecast maximum temperature................... 46.0 F/8.2 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................. 5616 ft MSL (776 ft AGL)
Thermal soaring outlook for Tuesday 01/20...... Poor

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

Remarks...

Sunrise/Sunset.................... 07:29:55 / 17:18:53 MST
Total possible sunshine........... 9 hr 48 min 59 sec (588 min 59 sec)
Altitude of sun at 12:24:47 MST... 30.67 degrees

Upper air data from rawinsonde observation taken on 01/19/2015 at 0500 MST

Freezing level.................. 5042 ft MSL (203 ft AGL)
Additional freezing levels...... 8822 ft MSL (3983 ft AGL)
                                 9676 ft MSL (4837 ft AGL)
Convective condensation level... 15031 ft MSL (10192 ft AGL)
Lifted condensation level....... 10561 ft MSL (5722 ft AGL)
Lifted index.................... +8.7
K index......................... +13.4

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  -61.0 -77.8   290   47   24   4.7   2.6  101.5 214.6    53.1      M    M
 45000  -58.1 -72.6   285   62   32   0.1   0.1   81.4 178.6    44.7      M    M
 40000  -59.7 -75.5   290   73   38  -0.2  -0.1   55.5 132.0    31.0      M    M
 38000  -59.8 -75.6   295   76   39  -2.9  -1.6   45.5 113.9    25.3      M    M
 36000  -59.8 -75.6   290   81   41   2.9   1.6   36.8  98.3    20.0      M    M
 34000  -55.6 -68.1   280   69   36   6.7   3.7   34.5  94.1    18.9      M    M
 32000  -51.6 -60.9   300   62   32   6.7   3.7   32.0  89.6    17.6      M    M
 30000  -46.8 -52.2   295   66   34   8.6   4.7   30.6  87.1    17.0      M    M
 29000  -44.2 -47.6   295   65   33   8.6   4.7   30.0  86.0    16.8      M    M
 28000  -41.6 -42.9   290   64   33   8.6   4.7   29.5  85.2    16.6      M    M
 27000  -39.0 -38.2   290   63   32   8.5   4.7   29.1  84.4    16.5      M    M
 26000  -36.5 -33.7   290   59   30   8.6   4.7   28.6  83.6    16.3      M    M
 25000  -33.9 -29.0   290   55   28   8.6   4.7   28.2  82.8    16.2      M    M
 24000  -31.5 -24.7   285   49   25   4.4   2.4   27.6  81.6    15.8      M    M
 23000  -30.2 -22.4   280   46   24   8.8   4.8   25.5  77.9    14.4      M    M
 22000  -27.6 -17.7   280   44   23   8.1   4.4   25.1  77.2    14.2      M    M
 21000  -25.2 -13.4   275   41   21   8.1   4.5   24.5  76.1    13.9      M    M
 20000  -22.1  -7.8   270   39   20   8.0   4.4   23.9  74.9    13.6      M    M
 19500  -20.8  -5.4   270   37   19   9.1   5.0   23.6  74.5    13.4      M    M
 19000  -19.5  -3.1   275   36   19   9.3   5.1   23.5  74.4    13.4      M    M
 18500  -18.0  -0.4   275   34   18   8.8   4.8   23.5  74.3    13.4      M    M
 18000  -16.8   1.8   275   32   16   8.1   4.4   23.2  73.7    13.3      M    M
 17500  -15.5   4.1   270   29   15   8.5   4.7   22.9  73.3    13.2      M    M
 17000  -14.3   6.3   270   27   14   8.5   4.6   22.7  72.9    13.1      M    M
 16500  -13.0   8.6   270   30   15   8.1   4.4   22.5  72.5    12.9      M    M
 16000  -11.9  10.6   270   32   16   7.4   4.0   22.0  71.6    12.6      M    M
 15500  -11.5  11.3   270   31   16  -1.7  -0.9   20.9  69.6    11.6      M    M
 15000  -11.3  11.7   270   31   16   4.6   2.5   19.6  67.3    10.4      M    M
 14500  -10.8  12.6   275   31   16   4.0   2.2   18.7  65.6     9.5      M    M
 14000   -9.8  14.4   280   31   16   8.8   4.8   18.1  64.7     9.1      M    M
 13500   -8.7  16.3   285   29   15   6.7   3.7   17.7  63.9     8.7      M    M
 13000   -7.8  18.0   290   27   14   7.8   4.3   17.2  63.0     8.3      M    M
 12500   -6.4  20.5   295   25   13   9.1   5.0   17.1  62.8     8.2      M    M
 12000   -5.0  23.0   300   24   12   9.2   5.0   17.0  62.6     8.2      M    M
 11500   -3.7  25.3   300   24   12   9.2   5.0   16.9  62.4     8.1      M    M
 11000   -2.3  27.9   305   23   12   9.1   5.0   16.8  62.2     8.0      M    M
 10500   -1.0  30.2   305   23   12   7.9   4.3   16.7  62.1     8.0      M    M
 10250   -0.5  31.1   305   23   12   5.5   3.0   16.4  61.6     7.7      M    M
 10000   -0.1  31.8   305   24   12   5.6   3.1   16.1  61.0     7.4      M    M
  9750    0.1  32.2   300   22   11  -0.7  -0.4   15.6  60.1     6.9      M    M
  9500   -0.2  31.6   290   19   10  -5.8  -3.2   14.5  58.1     5.9      M    M
  9250   -0.5  31.1   280   18    9  -0.1  -0.1   13.4  56.2     4.9      M    M
  9000   -0.3  31.5   265   17    9   3.4   1.9   12.9  55.2     4.4      M    M
  8750    0.0  32.0   265   14    7   6.0   3.3   12.4  54.4     4.0      M    M
  8500    0.7  33.3   265   10    5   8.5   4.6   12.3  54.1     3.9      M    M
  8250    1.3  34.3   260    6    3   8.2   4.5   12.1  53.9     3.7      M    M
  8000    1.8  35.2   255    3    1   5.3   2.9   12.0  53.6     3.6      M    M
  7750    2.1  35.8   255    1    1   4.1   2.2   11.5  52.7     3.1      M    M
  7500    2.4  36.3   275    1    0   0.2   0.1   11.0  51.9     2.7      M    M
  7250    2.1  35.8   320    1    0  -5.1  -2.8   10.0  50.0     1.7      M    M
  7000    1.7  35.1   010    1    0  -5.4  -3.0    8.9  48.0     0.6      M    M
  6750    1.3  34.3   085    1    1  -2.4  -1.3    7.7  45.9    -0.5    163  0.8
  6500    1.4  34.5   115    2    1   4.0   2.2    7.1  44.8    -1.2    154  0.8
  6250    1.8  35.2   120    4    2   5.4   3.0    6.7  44.1    -1.5    135  0.7
  6000    2.2  36.0   125    6    3   5.3   2.9    6.4  43.5    -1.9    117  0.6
  5750    2.5  36.5   130    6    3   4.6   2.5    6.0  42.9    -2.3     98  0.5
  5500    2.4  36.3   140    5    3 -12.4  -6.8    5.2  41.3    -3.1     95  0.5
  5250    1.0  33.8   150    5    3 -17.1  -9.4    3.0  37.4    -5.3    130  0.7
  5000    0.4  32.7   150    4    2   0.2   0.1    1.7  35.0    -6.6    140  0.7

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

           01/19/2015 at 0800 MST          |       01/19/2015 at 1100 MST
                                           |
K index... +11.9  LI... +2.1               | K index... +11.5  LI... +1.9
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.2
                                           |
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 -61.0 -77.8  290  48 25   1.9   1.1 | -60.9 -77.6  285  49 25   2.2   1.2
 45000 -58.1 -72.6  285  65 34   1.7   0.9 | -57.6 -71.7  285  67 34   2.1   1.1
 40000 -59.9 -75.8  290  71 37  -1.3  -0.7 | -59.8 -75.6  290  77 40  -1.6  -0.9
 38000 -59.8 -75.6  290  73 37   2.5   1.4 | -59.8 -75.6  290  78 40   2.2   1.2
 36000 -58.1 -72.6  290  73 38   2.4   1.3 | -58.4 -73.1  290  73 38   2.1   1.2
 34000 -56.0 -68.8  290  72 37   8.0   4.4 | -56.4 -69.5  285  69 36   8.4   4.6
 32000 -51.2 -60.2  290  67 34   7.9   4.3 | -51.5 -60.7  285  65 34   8.2   4.5
 30000 -46.3 -51.3  290  62 32   8.8   4.8 | -46.6 -51.9  285  61 31   8.3   4.6
 29000 -43.7 -46.7  295  60 31   8.8   4.8 | -44.1 -47.4  290  57 30   8.4   4.6
 28000 -41.0 -41.8  295  58 30   8.8   4.8 | -41.6 -42.9  290  54 28   8.4   4.6
 27000 -38.4 -37.1  295  57 29   7.9   4.3 | -39.1 -38.4  295  51 26   7.7   4.2
 26000 -36.2 -33.2  300  54 28   7.3   4.0 | -36.9 -34.4  295  48 24   7.2   4.0
 25000 -34.0 -29.2  300  51 26   7.3   4.0 | -34.7 -30.5  295  44 23   7.3   4.0
 24000 -31.8 -25.2  300  49 25   7.2   3.9 | -32.6 -26.7  295  41 21   7.5   4.1
 23000 -29.8 -21.6  300  43 22   6.9   3.8 | -30.2 -22.4  290  39 20   7.9   4.3
 22000 -27.7 -17.9  295  38 20   6.9   3.8 | -27.9 -18.2  290  37 19   7.9   4.3
 21000 -25.6 -14.1  290  34 17   8.1   4.5 | -25.5 -13.9  285  35 18   8.0   4.4
 20000 -22.5  -8.5  290  33 17   8.4   4.6 | -22.5  -8.5  285  34 18   8.1   4.4
 19500 -21.3  -6.3  290  33 17   8.4   4.6 | -21.3  -6.3  285  34 18   8.1   4.4
 19000 -20.0  -4.0  290  33 17   8.4   4.6 | -20.1  -4.2  285  34 18   8.1   4.5
 18500 -18.8  -1.8  290  33 17   8.3   4.5 | -18.8  -1.8  285  34 17   8.9   4.9
 18000 -17.5   0.5  290  33 17   8.3   4.6 | -17.5   0.5  285  34 17   8.9   4.9
 17500 -16.3   2.7  290  34 17   8.4   4.6 | -16.2   2.8  285  34 17   7.9   4.3
 17000 -15.0   5.0  290  34 17   8.4   4.6 | -15.1   4.8  285  33 17   7.5   4.1
 16500 -13.8   7.2  290  34 17   8.2   4.5 | -14.0   6.8  285  33 17   7.4   4.0
 16000 -12.6   9.3  290  33 17   7.6   4.2 | -12.9   8.8  285  33 17   7.0   3.8
 15500 -11.5  11.3  285  33 17   7.7   4.2 | -11.9  10.6  290  32 17   7.0   3.9
 15000 -10.5  13.1  285  31 16   6.0   3.3 | -10.9  12.4  290  31 16   6.0   3.3
 14500  -9.6  14.7  290  29 15   6.2   3.4 | -10.0  14.0  285  29 15   6.2   3.4
 14000  -8.7  16.3  290  27 14   5.2   2.8 |  -9.2  15.4  285  27 14   5.0   2.7
 13500  -8.0  17.6  290  25 13   5.2   2.8 |  -8.5  16.7  285  25 13   5.0   2.7
 13000  -7.2  19.0  295  22 11   5.5   3.0 |  -7.7  18.1  285  22 11   5.9   3.2
 12500  -6.4  20.5  300  19 10   5.4   3.0 |  -6.9  19.6  285  20 10   6.0   3.3
 12000  -5.6  21.9  300  17  9   7.7   4.2 |  -6.0  21.2  285  18  9   7.3   4.0
 11500  -4.4  24.1  305  15  8   8.1   4.4 |  -4.9  23.2  285  16  8   7.5   4.1
 11000  -3.2  26.2  305  14  7   8.5   4.7 |  -3.8  25.2  280  14  7   8.1   4.4
 10500  -1.9  28.6  305  13  7   9.2   5.0 |  -2.6  27.3  275  13  7   8.5   4.7
 10250  -1.3  29.7  305  12  6   6.3   3.5 |  -2.0  28.4  275  13  6   6.7   3.7
 10000  -1.0  30.2  300  12  6   3.6   2.0 |  -1.6  29.1  270  12  6   5.4   3.0
  9750  -0.6  30.9  295  10  5   4.8   2.6 |  -1.1  30.0  265  12  6   6.6   3.6
  9500  -0.3  31.5  290   9  5   5.0   2.8 |  -0.6  30.9  265  11  6   6.8   3.7
  9250   0.1  32.2  280   8  4   4.1   2.3 |  -0.1  31.8  260  11  5   5.8   3.2
  9000   0.3  32.5  275   7  4   3.5   1.9 |   0.2  32.4  255  10  5   4.6   2.5
  8750   0.6  33.1  270   7  4   4.7   2.6 |   0.6  33.1  255   9  5   4.3   2.3
  8500   1.0  33.8  260   6  3   5.3   2.9 |   0.8  33.4  250   8  4   4.0   2.2
  8250   1.3  34.3  255   6  3   5.5   3.0 |   1.2  34.2  250   7  4   4.5   2.5
  8000   1.8  35.2  250   6  3   5.8   3.2 |   1.5  34.7  250   7  4   4.8   2.6
  7750   2.2  36.0  245   5  3   5.1   2.8 |   1.9  35.4  250   6  3   4.6   2.5
  7500   2.6  36.7  235   5  3   4.5   2.4 |   2.2  36.0  245   6  3   4.6   2.5
  7250   2.9  37.2  215   5  3   4.4   2.4 |   2.6  36.7  235   5  3   4.5   2.5
  7000   3.3  37.9  200   6  3   4.4   2.4 |   2.9  37.2  220   5  3   4.7   2.6
  6750   3.7  38.7  190   7  3   4.5   2.5 |   3.3  37.9  210   6  3   4.1   2.3
  6500   4.0  39.2  180   7  4   2.3   1.3 |   3.6  38.5  200   5  3   3.0   1.6
  6250   4.0  39.2  170   7  4   0.3   0.2 |   3.7  38.7  195   5  2   2.8   1.5
  6000   4.1  39.4  160   7  4   1.9   1.0 |   3.9  39.0  190   4  2   2.8   1.6
  5750   3.8  38.8  155   7  4 -15.0  -8.2 |   4.2  39.6  180   3  2   7.0   3.8
  5500   1.5  34.7  145   6  3 -43.7 -24.0 |   5.0  41.0  180   3  1  13.8   7.6
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/19/2015 at 1400 MST          |       01/19/2015 at 1700 MST
                                           |
K index... +6.6  LI... +2.4                | K index... +16.4  LI... +2.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -15.7
                                           |
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 -60.4 -76.7  290  54 28   2.2   1.2 | -60.4 -76.7  290  53 27   2.0   1.1
 45000 -57.0 -70.6  290  67 35   2.4   1.3 | -57.2 -71.0  290  67 34   2.1   1.1
 40000 -59.0 -74.2  290  80 41  -1.5  -0.8 | -57.9 -72.2  290  80 41  -0.6  -0.3
 38000 -59.2 -74.6  285  82 42   1.8   1.0 | -57.9 -72.2  285  82 42   1.3   0.7
 36000 -58.1 -72.6  285  77 40   1.8   1.0 | -57.1 -70.8  285  78 40   1.3   0.7
 34000 -56.3 -69.3  285  72 37   7.7   4.2 | -56.2 -69.2  285  74 38   4.5   2.5
 32000 -51.9 -61.4  285  66 34   7.3   4.0 | -52.1 -61.8  280  66 34   6.0   3.3
 30000 -47.4 -53.3  285  59 30   8.2   4.5 | -48.2 -54.8  280  59 30   9.1   5.0
 29000 -44.9 -48.8  285  55 28   8.3   4.5 | -45.4 -49.7  280  57 29   9.1   5.0
 28000 -42.4 -44.3  285  52 27   8.3   4.5 | -42.7 -44.9  280  54 28   9.1   5.0
 27000 -39.9 -39.8  285  48 25   8.5   4.7 | -40.0 -40.0  280  52 27   9.0   4.9
 26000 -37.3 -35.1  285  47 24   8.8   4.8 | -37.3 -35.1  280  50 26   8.9   4.9
 25000 -34.7 -30.5  280  46 24   8.8   4.8 | -34.7 -30.5  280  48 25   8.9   4.9
 24000 -32.1 -25.8  280  45 23   8.6   4.7 | -32.0 -25.6  280  46 24   8.7   4.8
 23000 -29.6 -21.3  280  44 23   8.1   4.5 | -29.6 -21.3  285  44 23   7.8   4.3
 22000 -27.2 -17.0  280  43 22   8.1   4.5 | -27.3 -17.1  285  43 22   7.8   4.3
 21000 -24.8 -12.6  280  42 22   7.2   3.9 | -25.0 -13.0  285  42 22   7.1   3.9
 20000 -22.3  -8.1  280  38 20   6.8   3.7 | -23.0  -9.4  290  39 20   6.8   3.7
 19500 -21.3  -6.3  285  37 19   6.8   3.7 | -22.0  -7.6  290  38 19   6.8   3.7
 19000 -20.3  -4.5  285  35 18   6.9   3.8 | -21.0  -5.8  290  36 19   6.8   3.7
 18500 -19.4  -2.9  285  34 17   6.1   3.3 | -20.0  -4.0  290  35 18   5.8   3.2
 18000 -18.5  -1.3  290  32 17   6.2   3.4 | -19.2  -2.6  295  32 17   5.1   2.8
 17500 -17.5   0.5  290  31 16   7.1   3.9 | -18.5  -1.3  295  30 16   5.0   2.7
 17000 -16.3   2.7  290  30 16   7.7   4.2 | -17.8  -0.0  300  28 15   3.8   2.1
 16500 -15.2   4.6  290  30 15   7.8   4.3 | -17.2   1.0  300  27 14   3.7   2.0
 16000 -13.9   7.0  290  29 15   8.0   4.4 | -16.5   2.3  300  26 13   7.0   3.8
 15500 -12.7   9.1  290  28 15   8.2   4.5 | -15.4   4.3  300  26 13   7.4   4.1
 15000 -11.6  11.1  290  28 14   6.8   3.7 | -13.6   7.5  295  26 13   9.3   5.1
 14500 -10.5  13.1  285  27 14   7.1   3.9 | -12.2  10.0  295  26 13   9.2   5.1
 14000  -9.6  14.7  285  26 13   5.2   2.9 | -10.9  12.4  290  26 13   8.0   4.4
 13500  -8.9  16.0  285  24 12   5.1   2.8 |  -9.7  14.5  290  25 13   8.1   4.5
 13000  -8.1  17.4  285  22 11   6.6   3.6 |  -8.6  16.5  290  24 12   7.1   3.9
 12500  -7.1  19.2  285  20 11   7.0   3.8 |  -7.6  18.3  285  22 12   7.1   3.9
 12000  -6.1  21.0  280  19 10   7.4   4.1 |  -6.5  20.3  285  21 11   7.8   4.3
 11500  -5.0  23.0  280  17  9   7.6   4.2 |  -5.4  22.3  285  20 10   7.9   4.3
 11000  -3.9  25.0  275  16  8   7.4   4.1 |  -4.3  24.3  285  19 10   8.0   4.4
 10500  -2.9  26.8  275  15  8   8.0   4.4 |  -3.1  26.4  280  18  9   9.0   5.0
 10250  -2.3  27.9  270  15  7   4.8   2.6 |  -2.5  27.5  280  18  9   4.0   2.2
 10000  -2.1  28.2  270  14  7   4.4   2.4 |  -2.4  27.7  280  17  9   4.4   2.4
  9750  -1.6  29.1  270  14  7   8.2   4.5 |  -1.7  28.9  275  17  9   9.5   5.2
  9500  -1.0  30.2  265  13  7   8.5   4.7 |  -1.1  30.0  275  16  8   8.5   4.7
  9250  -0.4  31.3  265  13  7   6.9   3.8 |  -0.5  31.1  275  16  8   6.4   3.5
  9000   0.0  32.0  265  12  6   5.0   2.7 |  -0.1  31.8  270  15  8   5.2   2.8
  8750   0.4  32.7  260  11  6   5.5   3.0 |   0.4  32.7  270  14  7   7.2   4.0
  8500   0.8  33.4  260  10  5   5.6   3.1 |   0.9  33.6  270  13  7   6.6   3.6
  8250   1.2  34.2  255   9  5   4.5   2.5 |   1.3  34.3  265  12  6   5.1   2.8
  8000   1.5  34.7  255   8  4   3.8   2.1 |   1.6  34.9  265  11  5   4.4   2.4
  7750   1.8  35.2  255   7  4   3.8   2.1 |   2.0  35.6  260   9  5   4.6   2.5
  7500   2.1  35.8  250   6  3   3.6   2.0 |   2.3  36.1  260   7  4   3.9   2.1
  7250   2.4  36.3  245   5  3   3.9   2.1 |   2.5  36.5  255   6  3   3.2   1.8
  7000   2.6  36.7  240   4  2   3.8   2.1 |   2.8  37.0  250   4  2   3.5   1.9
  6750   2.9  37.2  235   3  2   4.3   2.4 |   3.1  37.6  240   3  2   4.6   2.5
  6500   3.4  38.1  230   3  2   7.5   4.1 |   3.4  38.1  235   3  1   5.2   2.9
  6250   4.0  39.2  230   3  1   9.4   5.2 |   3.8  38.8  235   2  1   5.4   2.9
  6000   4.6  40.3  235   3  1   8.6   4.7 |   4.2  39.6  245   1  1   4.6   2.5
  5750   5.2  41.4  240   2  1  10.1   5.6 |   4.4  39.9  280   1  1   3.0   1.6
  5500   6.1  43.0  245   2  1  14.0   7.7 |   4.6  40.3  285   1  1   2.6   1.4
  5250     M     M    M   M  M     M     M |   4.8  40.6  290   1  0   2.8   1.6
  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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