Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 291317
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0617 MST Thursday, January 29, 2015

This forecast is for Thursday, January 29, 2015:

If the trigger temperature of 52.8 F/11.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 6 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8232 ft MSL (3393 ft AGL)

Forecast maximum temperature................... 52.0 F/11.6 C
Time of trigger temperature.................... 1400 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5708 ft MSL (869 ft AGL)
Thermal soaring outlook for Friday 01/30....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:23:18 / 17:30:15 MST
Total possible sunshine........... 10 hr 6 min 57 sec (606 min 57 sec)
Altitude of sun at 12:27:09 MST... 33.08 degrees

Upper air data from rawinsonde observation taken on 01/29/2015 at 0500 MST

Freezing level.................. 8648 ft MSL (3809 ft AGL)
Convective condensation level... 12229 ft MSL (7390 ft AGL)
Lifted condensation level....... 11018 ft MSL (6179 ft AGL)
Lifted index.................... +8.1
K index......................... +8.4

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  -61.8 -79.2   270   44   23   5.4   2.9   97.7 207.9    49.4      M    M
 45000  -56.6 -69.9   275   44   23   5.9   3.2   81.8 179.2    43.1      M    M
 40000  -58.3 -72.9   275   69   35 -18.5 -10.2   56.1 133.0    29.4      M    M
 38000  -58.7 -73.7   270  100   52  -6.4  -3.5   46.5 115.8    23.8      M    M
 36000  -55.6 -68.1   265  113   58   6.7   3.7   42.4 108.4    21.6      M    M
 34000  -51.0 -59.8   265   94   49   7.5   4.1   39.7 103.5    20.3      M    M
 32000  -46.2 -51.2   255   75   38   8.0   4.4   38.2 100.8    19.7      M    M
 30000  -41.5 -42.7   260   64   33   7.6   4.2   36.7  98.1    19.1      M    M
 29000  -39.2 -38.6   260   58   30   7.6   4.2   35.9  96.5    18.7      M    M
 28000  -37.0 -34.6   265   53   27   7.3   4.0   34.9  94.7    18.2      M    M
 27000  -34.8 -30.6   265   48   25   7.1   3.9   33.9  93.1    17.7      M    M
 26000  -32.3 -26.1   265   43   22   8.8   4.8   33.4  92.2    17.5      M    M
 25000  -30.3 -22.5   270   38   20   4.8   2.6   32.3  90.1    16.8      M    M
 24000  -28.2 -18.8   275   35   18   7.4   4.1   31.2  88.2    16.2      M    M
 23000  -27.0 -16.6   275   30   15   5.4   2.9   29.1  84.3    14.6      M    M
 22000  -24.7 -12.5   280   24   12   7.8   4.3   28.3  83.0    14.1      M    M
 21000  -22.4  -8.3   285   18   10   7.8   4.3   27.7  81.9    13.8      M    M
 20000  -20.1  -4.2   295   20   10   7.9   4.3   27.0  80.6    13.3      M    M
 19500  -18.9  -2.0   295   18    9   7.9   4.3   26.7  80.0    13.1      M    M
 19000  -17.7   0.1   295   16    8   7.2   3.9   26.4  79.5    13.0      M    M
 18500  -16.5   2.3   290   15    8   5.1   2.8   25.3  77.5    12.1      M    M
 18000  -15.7   3.7   285   15    7   5.1   2.8   24.4  76.0    11.4      M    M
 17500  -15.0   5.0   295   12    6   5.2   2.8   23.6  74.5    10.8      M    M
 17000  -14.0   6.8   300   11    5   6.9   3.8   23.0  73.4    10.3      M    M
 16500  -13.0   8.6   315    8    4   6.8   3.7   22.5  72.5     9.9      M    M
 16000  -12.0  10.4   330    6    3   6.8   3.7   22.0  71.6     9.5      M    M
 15500  -11.0  12.2   330    3    2   6.8   3.8   21.5  70.7     9.1      M    M
 15000  -10.0  14.0   000    0    0   6.9   3.8   21.0  69.8     8.7      M    M
 14500   -9.0  15.8   160    1    1   6.7   3.7   20.5  68.9     8.3      M    M
 14000   -8.0  17.6   160    2    1   8.5   4.6   20.0  68.0     7.9      M    M
 13500   -8.2  17.2   125    1    1 -11.5  -6.3   18.2  64.7     6.2      M    M
 13000   -9.2  15.4   080    1    1  -0.8  -0.4   15.6  60.0     3.7      M    M
 12500   -8.5  16.7   055    2    1   9.3   5.1   14.8  58.6     3.0      M    M
 12000   -7.2  19.0   045    3    2   8.9   4.9   14.7  58.4     2.9      M    M
 11500   -5.9  21.4   050    5    3   8.7   4.8   14.5  58.2     2.8      M    M
 11000   -4.5  23.9   050    8    4   5.6   3.1   14.4  57.9     2.7      M    M
 10500   -4.2  24.4   050   10    5   6.5   3.6   13.3  55.9     1.5      M    M
 10250   -3.6  25.5   050   11    6   8.6   4.7   13.2  55.7     1.4      M    M
 10000   -3.0  26.6   055   11    5   7.0   3.9   13.0  55.4     1.3      M    M
  9750   -2.5  27.5   060   10    5   7.5   4.1   12.8  55.1     1.1      M    M
  9500   -1.9  28.6   070   10    5   7.3   4.0   12.6  54.7     0.9      M    M
  9250   -1.4  29.5   075   10    5   7.4   4.0   12.5  54.4     0.7      M    M
  9000   -0.8  30.6   080   10    5   7.4   4.0   12.3  54.1     0.6      M    M
  8750   -0.3  31.5   075   10    5   7.4   4.0   12.1  53.8     0.4      M    M
  8500    0.3  32.5   070   11    6   7.4   4.0   11.9  53.4     0.2      M    M
  8250    0.8  33.4   070   11    6   7.4   4.0   11.7  53.1     0.0      M    M
  8000    1.4  34.5   065   12    6   7.4   4.0   11.5  52.8    -0.1    188  1.0
  7750    1.9  35.4   060   11    6   7.4   4.0   11.4  52.4    -0.3    164  0.8
  7500    2.4  36.3   060   10    5   7.4   4.0   11.2  52.1    -0.5    140  0.7
  7250    3.0  37.4   055    8    4   7.4   4.0   11.0  51.8    -0.7    116  0.6
  7000    3.5  38.3   045    7    4   7.3   4.0   10.8  51.4    -0.9     93  0.5
  6750    4.1  39.4   050    6    3   7.5   4.1   10.6  51.1    -1.1     69  0.3
  6500    4.6  40.3   060    5    3   7.0   3.8   10.4  50.7    -1.3     45  0.2
  6250    5.1  41.2   075    4    2   3.8   2.1   10.1  50.2    -1.6     25  0.1
  6000    5.2  41.4   090    4    2   2.1   1.2    9.5  49.2    -2.2     13  0.1
  5750    5.4  41.7   100    5    2   2.2   1.2    9.0  48.2    -2.7      0  0.0
  5500    5.6  42.1   105    5    3   3.6   2.0    8.4  47.2    -3.3      M    M
  5250    5.7  42.3   110    6    3  -1.9  -1.1    7.9  46.2    -3.9      M    M
  5000    4.9  40.8   115    6    3 -23.4 -12.8    6.3  43.3    -5.5      M    M

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

           01/29/2015 at 0800 MST          |       01/29/2015 at 1100 MST
                                           |
K index... +3.1  LI... +6.2                | K index... +5.1  LI... +4.7
CAPE... 0.0  CIN... -1.1                   | CAPE... 0.0  CIN... -0.8
                                           |
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 -61.4 -78.5  285  35 18   2.6   1.4 | -62.0 -79.6  275  31 16   2.7   1.5
 45000 -57.7 -71.9  275  47 24   0.1   0.1 | -58.0 -72.4  270  42 22   0.3   0.1
 40000 -57.3 -71.1  270  64 33   0.2   0.1 | -57.5 -71.5  265  65 33   0.4   0.2
 38000 -55.9 -68.6  270  76 39   3.4   1.9 | -56.2 -69.2  260  72 37   3.1   1.7
 36000 -53.9 -65.0  265  89 46   3.4   1.9 | -54.4 -65.9  260  79 41   3.1   1.7
 34000 -51.2 -60.2  265  96 49   7.4   4.0 | -50.9 -59.6  260  81 42   8.8   4.8
 32000 -46.2 -51.2  265  81 42   7.5   4.1 | -45.6 -50.1  260  75 39   8.8   4.8
 30000 -41.6 -42.9  270  67 34   7.9   4.3 | -40.8 -41.4  265  65 34   7.2   4.0
 29000 -39.2 -38.6  270  59 30   7.9   4.3 | -38.6 -37.5  265  58 30   7.2   4.0
 28000 -36.9 -34.4  275  51 26   7.9   4.3 | -36.4 -33.5  270  50 26   7.2   4.0
 27000 -34.6 -30.3  275  44 22   6.9   3.8 | -34.3 -29.7  275  43 22   7.3   4.0
 26000 -32.5 -26.5  280  39 20   7.0   3.8 | -32.1 -25.8  275  36 19   7.3   4.0
 25000 -30.4 -22.7  280  35 18   7.0   3.8 | -29.9 -21.8  280  30 15   7.3   4.0
 24000 -28.3 -18.9  280  31 16   6.8   3.7 | -27.8 -18.0  280  24 12   6.3   3.4
 23000 -26.3 -15.3  280  26 14   6.7   3.7 | -26.0 -14.8  280  21 11   6.1   3.4
 22000 -24.3 -11.7  275  22 11   6.7   3.7 | -24.1 -11.4  275  18  9   6.1   3.4
 21000 -22.2  -8.0  275  19 10   7.4   4.1 | -22.2  -8.0  270  15  8   6.9   3.8
 20000 -20.0  -4.0  280  17  9   7.3   4.0 | -20.2  -4.4  275  12  6   6.9   3.8
 19500 -18.9  -2.0  280  16  8   7.3   4.0 | -19.2  -2.6  275  11  6   6.9   3.8
 19000 -17.9  -0.2  285  15  8   7.4   4.1 | -17.6   0.3  280   9  4   6.7   3.7
 18500 -16.3   2.7  290  13  6   6.4   3.5 | -16.7   1.9  280   7  3   6.2   3.4
 18000 -15.4   4.3  290  11  6   6.4   3.5 | -15.8   3.6  280   5  2   6.1   3.4
 17500 -14.4   6.1  295   9  5   6.8   3.7 | -14.8   5.4  275   3  1   6.9   3.8
 17000 -13.3   8.1  305   8  4   6.8   3.7 | -13.8   7.2  260   1  1   6.9   3.8
 16500 -12.3   9.9  310   7  4   6.3   3.5 | -12.7   9.1  145   1  0   6.3   3.5
 16000 -11.5  11.3  325   6  3   5.9   3.2 | -11.9  10.6  120   2  1   6.0   3.3
 15500 -10.6  12.9  340   4  2   5.7   3.1 | -11.0  12.2  115   4  2   6.0   3.3
 15000  -9.8  14.4  360   4  2   4.8   2.7 | -10.1  13.8  120   5  3   6.1   3.3
 14500  -9.1  15.6  025   4  2   4.9   2.7 |  -9.2  15.4  120   6  3   6.0   3.3
 14000  -8.5  16.7  050   4  2   4.2   2.3 |  -8.4  16.9  125   7  3   5.1   2.8
 13500  -7.9  17.8  065   5  2   4.2   2.3 |  -7.6  18.3  130   7  4   5.2   2.8
 13000  -7.2  19.0  075   6  3   4.7   2.6 |  -6.9  19.6  130   7  4   5.6   3.1
 12500  -6.6  20.1  080   7  4   4.6   2.5 |  -6.1  21.0  130   8  4   5.6   3.1
 12000  -5.8  21.6  080   8  4   5.5   3.0 |  -5.3  22.5  135   8  4   5.8   3.2
 11500  -5.0  23.0  085   9  5   5.4   3.0 |  -4.4  24.1  135   8  4   5.9   3.2
 11000  -4.2  24.4  085  10  5   6.2   3.4 |  -3.6  25.5  135   8  4   5.6   3.1
 10500  -3.3  26.1  085  11  6   6.5   3.6 |  -2.8  27.0  140   8  4   5.8   3.2
 10250  -2.9  26.8  080  12  6   5.2   2.8 |  -2.4  27.7  140   8  4   4.6   2.5
 10000  -2.6  27.3  080  11  6   4.7   2.6 |  -2.1  28.2  140   8  4   5.0   2.7
  9750  -2.2  28.0  080  11  6   6.1   3.3 |  -1.7  28.9  140   8  4   7.2   3.9
  9500  -1.7  28.9  080  11  6   6.0   3.3 |  -1.1  30.0  140   7  4   6.8   3.7
  9250  -1.3  29.7  080  11  6   5.2   2.9 |  -0.7  30.7  140   7  4   5.0   2.7
  9000  -1.0  30.2  080  11  6   4.8   2.6 |  -0.4  31.3  140   7  4   4.2   2.3
  8750  -0.6  30.9  080  12  6   6.0   3.3 |  -0.0  32.0  135   7  3   5.7   3.1
  8500  -0.2  31.6  080  12  6   5.9   3.3 |   0.4  32.7  130   6  3   5.5   3.0
  8250   0.2  32.4  075  12  6   5.0   2.7 |   0.7  33.3  125   6  3   4.3   2.4
  8000   0.6  33.1  075  12  6   4.7   2.6 |   1.1  34.0  125   6  3   4.3   2.4
  7750   1.0  33.8  075  12  6   5.7   3.1 |   1.4  34.5  115   6  3   4.5   2.4
  7500   1.4  34.5  070  12  6   5.4   3.0 |   1.7  35.1  110   5  3   4.1   2.3
  7250   1.7  35.1  070  12  6   4.3   2.4 |   2.0  35.6  105   5  3   3.8   2.1
  7000   2.1  35.8  070  12  6   4.7   2.6 |   2.3  36.1  100   5  3   3.7   2.1
  6750   2.4  36.3  065  12  6   4.4   2.4 |   2.6  36.7  095   5  2   4.2   2.3
  6500   2.7  36.9  065  11  6   2.2   1.2 |   2.9  37.2  090   4  2   4.9   2.7
  6250   2.8  37.0  070  10  5   1.5   0.8 |   3.2  37.8  085   4  2   4.2   2.3
  6000   2.9  37.2  070   9  5  -0.3  -0.2 |   3.5  38.3  080   3  1   6.5   3.6
  5750   2.6  36.7  070   9  5  -8.9  -4.9 |   4.2  39.6  080   3  1  13.0   7.1
  5500   1.5  34.7  075   7  3 -16.3  -9.0 |   5.4  41.7  080   3  1  16.9   9.3
  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

           01/29/2015 at 1400 MST          |       01/29/2015 at 1700 MST
                                           |
K index... +2.0  LI... +5.3                | K index... +13.3  LI... +3.2
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.5
                                           |
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 -61.5 -78.7  275  35 18   2.4   1.3 | -61.3 -78.3  275  34 17   3.0   1.6
 45000 -57.9 -72.2  265  46 24  -0.1  -0.1 | -56.9 -70.4  270  47 24  -0.6  -0.3
 40000 -57.9 -72.2  260  75 39   0.0   0.0 | -57.5 -71.5  255  78 40  -0.4  -0.2
 38000 -56.6 -69.9  255  80 41   3.3   1.8 | -56.6 -69.9  255  82 42   2.6   1.4
 36000 -54.7 -66.5  255  82 42   3.3   1.8 | -55.0 -67.0  250  81 42   2.6   1.4
 34000 -51.2 -60.2  250  79 41   8.3   4.6 | -51.7 -61.1  250  76 39   8.9   4.9
 32000 -46.2 -51.2  260  69 35   8.3   4.6 | -46.4 -51.5  260  67 35   8.9   4.9
 30000 -41.2 -42.2  260  58 30   8.5   4.6 | -41.2 -42.2  265  58 30   8.5   4.6
 29000 -38.7 -37.7  265  52 27   8.5   4.6 | -38.7 -37.7  265  53 27   8.5   4.7
 28000 -36.1 -33.0  265  46 24   8.5   4.7 | -36.1 -33.0  265  48 25   8.5   4.7
 27000 -33.7 -28.7  270  40 21   7.4   4.1 | -33.7 -28.7  270  42 22   7.6   4.2
 26000 -31.5 -24.7  265  33 17   7.5   4.1 | -31.4 -24.5  265  37 19   7.7   4.2
 25000 -29.2 -20.6  260  26 14   7.5   4.1 | -29.1 -20.4  260  31 16   7.8   4.3
 24000 -27.1 -16.8  250  21 11   5.9   3.3 | -26.8 -16.2  255  26 14   6.5   3.6
 23000 -25.4 -13.7  250  18  9   5.6   3.1 | -25.0 -13.0  255  24 12   6.2   3.4
 22000 -23.7 -10.7  255  15  8   5.6   3.1 | -23.1  -9.6  250  21 11   6.2   3.4
 21000 -22.0  -7.6  255  12  6   6.2   3.4 | -21.4  -6.5  245  18  9   5.1   2.8
 20000 -20.1  -4.2  250   9  5   6.2   3.4 | -19.8  -3.6  235  14  7   5.2   2.9
 19500 -19.2  -2.6  245   8  4   6.2   3.4 | -19.0  -2.2  225  12  6   5.2   2.9
 19000 -17.8  -0.0  235   6  3   6.4   3.5 | -17.9  -0.2  205  10  5   5.1   2.8
 18500 -16.8   1.8  225   5  3   7.0   3.8 | -17.2   1.0  200  10  5   4.6   2.5
 18000 -15.7   3.7  205   5  3   7.0   3.8 | -16.5   2.3  195  10  5   4.3   2.4
 17500 -14.7   5.5  195   6  3   6.5   3.6 | -15.6   3.9  190  10  5   7.4   4.1
 17000 -13.7   7.3  185   6  3   6.5   3.6 | -14.5   5.9  195  11  6   7.5   4.1
 16500 -12.8   9.0  175   7  4   6.3   3.4 | -13.4   7.9  195  11  6   7.4   4.1
 16000 -11.9  10.6  170   8  4   6.1   3.4 | -12.3   9.9  200  12  6   7.2   3.9
 15500 -11.0  12.2  165   8  4   6.0   3.3 | -11.2  11.8  200  12  6   6.8   3.8
 15000 -10.1  13.8  165   9  5   5.7   3.1 | -10.5  13.1  205  13  6   4.7   2.6
 14500  -9.3  15.3  170   9  5   5.8   3.2 |  -9.8  14.4  205  13  7   4.9   2.7
 14000  -8.5  16.7  170  10  5   5.3   2.9 |  -9.1  15.6  205  13  7   4.7   2.6
 13500  -7.7  18.1  170  10  5   5.3   2.9 |  -8.4  16.9  205  12  6   4.5   2.5
 13000  -6.9  19.6  170  11  5   5.9   3.2 |  -7.6  18.3  210  12  6   6.9   3.8
 12500  -6.0  21.2  170  11  5   5.8   3.2 |  -6.6  20.1  210  12  6   6.8   3.7
 12000  -5.2  22.6  170  11  6   6.2   3.4 |  -5.6  21.9  215  13  6   7.1   3.9
 11500  -4.3  24.3  170  11  6   6.2   3.4 |  -4.5  23.9  215  13  7   7.1   3.9
 11000  -3.3  26.1  170  11  6   6.9   3.8 |  -3.5  25.7  220  14  7   7.8   4.3
 10500  -2.3  27.9  170  12  6   7.1   3.9 |  -2.3  27.9  215  14  7   8.2   4.5
 10250  -1.8  28.8  170  12  6   5.6   3.1 |  -1.8  28.8  215  15  7   6.1   3.3
 10000  -1.5  29.3  165  12  6   5.7   3.1 |  -1.4  29.5  215  14  7   6.1   3.3
  9750  -0.9  30.4  165  11  6   7.5   4.1 |  -0.8  30.6  210  14  7   8.5   4.6
  9500  -0.4  31.3  165  11  6   7.1   3.9 |  -0.2  31.6  205  13  7   8.0   4.4
  9250   0.1  32.2  165  11  6   6.0   3.3 |   0.3  32.5  205  13  7   6.3   3.5
  9000   0.5  32.9  160  10  5   5.4   2.9 |   0.7  33.3  200  12  6   5.4   3.0
  8750   0.9  33.6  160  10  5   6.3   3.5 |   1.2  34.2  190  12  6   6.8   3.7
  8500   1.3  34.3  160  10  5   6.3   3.4 |   1.7  35.1  185  11  6   6.7   3.7
  8250   1.8  35.2  155   9  5   5.7   3.1 |   2.2  36.0  180  11  6   6.0   3.3
  8000   2.2  36.0  155   8  4   5.7   3.1 |   2.6  36.7  170  11  5   5.8   3.2
  7750   2.6  36.7  150   7  4   5.9   3.2 |   3.1  37.6  165  10  5   6.7   3.7
  7500   3.0  37.4  145   6  3   5.2   2.9 |   3.6  38.5  160   9  5   6.5   3.5
  7250   3.3  37.9  140   5  3   4.8   2.6 |   4.0  39.2  155   8  4   5.7   3.1
  7000   3.7  38.7  130   4  2   4.5   2.5 |   4.4  39.9  145   7  3   5.8   3.2
  6750   4.0  39.2  120   4  2   6.1   3.4 |   4.8  40.6  135   6  3   6.1   3.4
  6500   4.5  40.1  115   3  2   9.4   5.1 |   5.3  41.5  130   5  3   7.6   4.2
  6250   5.3  41.5  115   3  2  10.0   5.5 |   5.9  42.6  125   5  2   7.9   4.3
  6000   6.0  42.8  115   3  2  10.1   5.6 |   6.5  43.7  120   4  2   8.6   4.7
  5750   6.9  44.4  115   3  2  13.5   7.4 |   7.1  44.8  120   4  2   8.0   4.4
  5500   8.1  46.6  115   3  2  18.0   9.9 |   7.6  45.7  115   3  2   4.4   2.4
  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
________________________________________________________________________________

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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