Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 191237
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0637 MDT Saturday, August 19, 2017

This forecast is for Saturday, August 19, 2017:

If the trigger temperature of 87.4 F/30.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1511 ft/min (7.7 m/s)
   Maximum height of thermals.................. 20261 ft MSL (15422 ft AGL)

Forecast maximum temperature................... 95.0 F/35.5 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11738 ft MSL (6899 ft AGL)
Thermal soaring outlook for Sunday 08/20....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:31:17 / 20:04:32 MDT
Total possible sunshine........... 13 hr 33 min 16 sec (813 min 16 sec)
Altitude of sun at 13:17:33 MDT... 63.39 degrees

Upper air data from rawinsonde observation taken on 08/19/2017 at 0600 MDT

Freezing level.................. 15550 ft MSL (10711 ft AGL)
Convective condensation level... 18370 ft MSL (13531 ft AGL)
Lifted condensation level....... 19268 ft MSL (14429 ft AGL)
Lifted index.................... -0.9
K index......................... +21.3

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  -64.7 -84.5   265   36   18   1.1   0.6   87.9 190.2    30.5      M    M
 45000  -62.3 -80.1   255   52   27   4.5   2.5   66.1 151.0    19.3      M    M
 40000  -53.8 -64.8   255   46   24   6.5   3.6   56.7 134.0    14.4      M    M
 38000  -50.1 -58.2   250   50   26   5.5   3.0   53.4 128.1    12.6      M    M
 36000  -47.1 -52.8   250   40   21   5.4   3.0   49.3 120.7    10.0      M    M
 34000  -42.4 -44.3   255   35   18   8.4   4.6   47.5 117.5     9.0      M    M
 32000  -36.7 -34.1   260   30   16   8.4   4.6   46.5 115.6     8.5      M    M
 30000  -31.9 -25.4   260   27   14   6.6   3.6   45.1 113.2     7.7      M    M
 29000  -30.2 -22.4   260   21   11   7.2   3.9   43.5 110.4     6.5      M    M
 28000  -27.7 -17.9   260   16    8   6.2   3.4   42.9 109.3     6.2      M    M
 27000  -25.9 -14.6   255   11    6   6.3   3.4   41.6 106.9     5.2      M    M
 26000  -23.7 -10.7   225   10    5   8.4   4.6   40.6 105.1     4.5      M    M
 25000  -21.2  -6.2   235   11    6   8.3   4.6   40.2 104.3     4.1      M    M
 24000  -18.8  -1.8   240    9    5   7.8   4.3   39.4 102.9     3.5      M    M
 23000  -16.5   2.3   240    7    3   7.8   4.3   38.7 101.6     3.0      M    M
 22000  -14.2   6.4   245    4    2   7.8   4.3   38.1 100.6     2.5      M    M
 21000  -11.9  10.6   250    8    4   6.6   3.6   37.3  99.1     1.9      M    M
 20000  -11.3  11.7   250   12    6   4.8   2.6   34.6  94.3    -0.5   1505  7.6
 19500  -10.3  13.5   270   13    7   5.3   2.9   34.2  93.5    -0.9   1459  7.4
 19000   -9.6  14.7   285   16    8   8.6   4.7   33.4  92.2    -1.7   1424  7.2
 18500   -8.2  17.2   285   15    8   9.3   5.1   33.4  92.1    -1.8   1367  6.9
 18000   -6.8  19.8   280   14    7   9.3   5.1   33.3  92.0    -1.8   1310  6.7
 17500   -4.7  23.5   275   13    6   9.3   5.1   33.2  91.7    -2.0   1226  6.2
 17000   -3.4  25.9   275   12    6   9.5   5.2   33.1  91.6    -2.1   1170  5.9
 16500   -2.2  28.0   270   11    6   6.7   3.7   32.9  91.2    -2.4   1120  5.7
 16000   -1.1  30.0   265   10    5   9.9   5.5   32.6  90.7    -2.7   1072  5.4
 15500    0.4  32.7   265   11    5   9.8   5.4   32.6  90.7    -2.8   1013  5.1
 15000    1.9  35.4   265   11    6   9.8   5.4   32.6  90.8    -2.8    954  4.8
 14500    3.3  37.9   265   12    6   9.8   5.4   32.7  90.8    -2.7    896  4.5
 14000    4.8  40.6   265   12    6   9.8   5.4   32.7  90.9    -2.7    837  4.3
 13500    6.3  43.3   270   12    6   9.8   5.4   32.7  90.9    -2.8    778  4.0
 13000    7.7  45.9   270   11    6   9.8   5.4   32.7  90.9    -2.8    719  3.7
 12500    9.2  48.6   275   11    6   9.5   5.2   32.7  90.9    -2.8    661  3.4
 12000   10.5  50.9   280   11    6   9.0   4.9   32.6  90.7    -2.9    606  3.1
 11500   11.8  53.2   280   10    5   9.0   4.9   32.5  90.4    -3.1    552  2.8
 11000   13.1  55.6   275    8    4   9.0   4.9   32.3  90.2    -3.3    498  2.5
 10500   14.5  58.1   270    7    4   8.8   4.8   32.2  90.0    -3.4    444  2.3
 10250   15.1  59.2   270    7    3   8.4   4.6   32.1  89.8    -3.5    417  2.1
 10000   15.7  60.3   265    6    3   8.4   4.6   32.0  89.6    -3.6    391  2.0
  9750   16.4  61.5   260    5    3   8.4   4.6   31.9  89.5    -3.7    364  1.8
  9500   17.0  62.6   255    5    3   8.4   4.6   31.8  89.3    -3.8    338  1.7
  9250   17.6  63.7   250    4    2   8.4   4.6   31.7  89.1    -3.9    311  1.6
  9000   18.3  64.9   240    4    2   8.4   4.6   31.6  88.9    -4.0    285  1.4
  8750   18.9  66.0   240    4    2   8.4   4.6   31.5  88.7    -4.1    258  1.3
  8500   19.6  67.3   240    4    2   8.4   4.6   31.4  88.5    -4.2    232  1.2
  8250   20.2  68.4   245    3    2   8.2   4.5   31.3  88.3    -4.3    205  1.0
  8000   20.8  69.4   245    3    2   8.8   4.9   31.2  88.1    -4.4    179  0.9
  7750   21.5  70.7   210    4    2   6.6   3.6   31.1  87.9    -4.5    152  0.8
  7500   21.7  71.1   195    7    3  -0.4  -0.2   30.6  87.0    -5.0    138  0.7
  7250   21.5  70.7   185   10    5  -3.3  -1.8   29.6  85.3    -6.0    137  0.7
  7000   21.2  70.2   180   12    6  -2.5  -1.4   28.7  83.6    -7.0    137  0.7
  6750   21.0  69.8   170   13    7  -2.7  -1.5   27.7  81.9    -7.9    136  0.7
  6500   20.8  69.4   160   14    7  -2.6  -1.4   26.8  80.2    -8.9    135  0.7
  6250   20.6  69.1   155   16    8  -2.6  -1.4   25.8  78.5    -9.9    135  0.7
  6000   20.5  68.9   145   17    9   3.2   1.7   25.0  77.1   -10.7    130  0.7
  5750   20.9  69.6   140   16    8   6.6   3.6   24.8  76.6   -11.0    109  0.6
  5500   21.4  70.5   135   13    7   7.8   4.3   24.5  76.1   -11.3     88  0.4
  5250   21.8  71.2   130   11    6  -0.4  -0.2   24.2  75.6   -11.6     68  0.3
  5000   20.8  69.4   120    9    5 -28.6 -15.7   22.5  72.5   -13.5     92  0.5

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

           08/19/2017 at 0900 MDT          |       08/19/2017 at 1200 MDT
                                           |
K index... +22.3  LI... -0.7               | K index... +22.0  LI... -0.8
CAPE... +13.5  CIN... -22.9                | CAPE... +32.1  CIN... -34.9
                                           |
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 -63.2 -81.8  265  30 16   0.3   0.2 | -63.0 -81.4  265  29 15   0.5   0.3
 45000 -60.9 -77.6  265  40 21   4.4   2.4 | -60.5 -76.9  265  40 21   4.4   2.4
 40000 -54.0 -65.2  260  40 20   5.8   3.2 | -53.8 -64.8  255  41 21   5.6   3.0
 38000 -50.5 -58.9  260  36 19   5.9   3.2 | -50.4 -58.7  255  37 19   5.6   3.1
 36000 -47.0 -52.6  260  33 17   5.7   3.1 | -47.1 -52.8  255  33 17   5.4   3.0
 34000 -42.3 -44.1  260  32 16   8.4   4.6 | -42.4 -44.3  255  32 17   8.2   4.5
 32000 -37.2 -35.0  260  31 16   8.3   4.6 | -37.5 -35.5  255  32 16   8.1   4.5
 30000 -32.0 -25.6  260  26 13   7.6   4.2 | -32.3 -26.1  255  28 14   7.6   4.2
 29000 -29.7 -21.5  260  23 12   7.7   4.2 | -30.0 -22.0  260  25 13   7.6   4.2
 28000 -27.5 -17.5  260  20 10   7.4   4.1 | -27.8 -18.0  260  23 12   7.4   4.1
 27000 -25.3 -13.5  265  18  9   7.4   4.1 | -25.6 -14.1  260  19 10   7.4   4.1
 26000 -23.0  -9.4  265  16  8   7.4   4.1 | -23.3  -9.9  265  15  8   7.5   4.1
 25000 -20.8  -5.4  270  13  7   7.1   3.9 | -21.1  -6.0  265  12  6   7.2   4.0
 24000 -18.9  -2.0  265  13  7   6.4   3.5 | -19.1  -2.4  265  11  6   6.5   3.6
 23000 -17.0   1.4  260  13  6   6.4   3.5 | -17.2   1.0  265  11  6   6.5   3.6
 22000 -15.0   5.0  260  12  6   6.4   3.5 | -15.2   4.6  265  11  6   6.6   3.6
 21000 -13.1   8.4  255  12  6   6.5   3.6 | -13.3   8.1  255  13  7   6.8   3.7
 20000 -11.3  11.7  250  13  7   6.6   3.6 | -11.3  11.7  250  15  8   6.8   3.8
 19500 -10.3  13.5  250  13  7   6.7   3.7 | -10.3  13.5  245  16  8   6.9   3.8
 19000  -9.2  15.4  250  13  7   8.7   4.7 |  -9.2  15.4  245  17  9   8.8   4.8
 18500  -8.0  17.6  250  13  7   8.5   4.7 |  -7.9  17.8  245  17  9   8.7   4.8
 18000  -6.7  19.9  245  14  7   8.5   4.7 |  -6.6  20.1  250  18  9   8.6   4.7
 17500  -5.5  22.1  250  13  7   8.5   4.7 |  -5.3  22.5  250  18  9   8.6   4.7
 17000  -4.3  24.3  250  12  6   8.6   4.7 |  -4.0  24.8  250  17  9   8.6   4.7
 16500  -3.0  26.6  255  11  6   8.5   4.6 |  -2.8  27.0  250  17  8   8.6   4.7
 16000  -1.8  28.8  260  10  5   8.4   4.6 |  -1.5  29.3  250  16  8   8.6   4.7
 15500  -0.5  31.1  265  10  5   9.2   5.1 |  -0.2  31.6  255  15  8   9.1   5.0
 15000   0.9  33.6  265  10  5   9.3   5.1 |   1.1  34.0  255  14  7   9.2   5.1
 14500   3.0  37.4  270  10  5   9.6   5.3 |   3.1  37.6  255  13  7   9.0   5.0
 14000   4.4  39.9  270  10  5   9.6   5.3 |   4.4  39.9  260  12  6   9.1   5.0
 13500   5.9  42.6  270  10  5   9.4   5.2 |   5.8  42.4  260  12  6   9.2   5.0
 13000   7.3  45.1  270  11  5   9.4   5.1 |   7.1  44.8  260  11  6   9.2   5.0
 12500   8.7  47.7  270  11  6   9.4   5.1 |   8.5  47.3  265  11  6   9.6   5.3
 12000  10.0  50.0  270  11  6   9.4   5.1 |   9.9  49.8  265  11  6   9.7   5.3
 11500  11.4  52.5  270  11  6   9.3   5.1 |  11.4  52.5  270  11  6   9.6   5.3
 11000  12.8  55.0  270  11  6   9.1   5.0 |  12.8  55.0  270  11  6   9.5   5.2
 10500  14.1  57.4  270  12  6   4.3   2.3 |  14.1  57.4  270  11  5   5.5   3.0
 10250  14.3  57.7  270  11  6   5.6   3.1 |  14.4  57.9  275  10  5   7.6   4.2
 10000  15.0  59.0  270  11  6  11.7   6.4 |  15.3  59.5  275  10  5  11.8   6.5
  9750  15.8  60.4  270  11  6  10.4   5.7 |  16.1  61.0  275  10  5  10.9   6.0
  9500  16.5  61.7  270  11  6   8.0   4.4 |  16.9  62.4  275   9  5   7.8   4.3
  9250  16.9  62.4  270  11  6   6.0   3.3 |  17.3  63.1  275   9  5   6.6   3.6
  9000  17.5  63.5  270  10  5   7.5   4.1 |  17.9  64.2  275   8  4   9.0   4.9
  8750  18.0  64.4  270  10  5   7.3   4.0 |  18.6  65.5  275   8  4   8.5   4.7
  8500  18.5  65.3  265   9  4   5.0   2.8 |  19.1  66.4  275   7  4   6.7   3.7
  8250  18.8  65.8  260   7  4   3.5   1.9 |  19.6  67.3  270   6  3   5.7   3.1
  8000  19.1  66.4  250   6  3   3.9   2.2 |  20.0  68.0  260   5  2   6.6   3.6
  7750  19.5  67.1  235   5  3   3.9   2.1 |  20.6  69.1  250   4  2   7.8   4.3
  7500  19.8  67.6  215   5  2   4.3   2.3 |  21.2  70.2  240   3  2   9.1   5.0
  7250  20.1  68.2  200   5  3   4.1   2.2 |  21.9  71.4  240   3  2   9.7   5.3
  7000  20.4  68.7  190   6  3   5.1   2.8 |  22.6  72.7  235   3  2   9.3   5.1
  6750  20.8  69.4  180   7  4   3.2   1.8 |  23.3  73.9  235   3  2  10.3   5.6
  6500  20.8  69.4  175   7  3   0.3   0.2 |  24.2  75.6  235   3  2  11.3   6.2
  6250  20.8  69.4  165   6  3   0.6   0.3 |  25.0  77.0  235   3  2  11.4   6.3
  6000  20.9  69.6  160   6  3   0.5   0.3 |  25.8  78.4  235   3  2  10.5   5.8
  5750  21.0  69.8  150   5  3   5.4   2.9 |  26.6  79.9  235   3  2  12.6   6.9
  5500  21.6  70.9  150   5  2   9.8   5.4 |  27.7  81.9  235   3  2  15.7   8.6
  5250  22.2  72.0  145   4  2   6.4   3.5 |  28.8  83.8  235   3  2  13.3   7.3
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/19/2017 at 1500 MDT          |       08/19/2017 at 1800 MDT
                                           |
K index... +23.0  LI... -0.0               | K index... +20.5  LI... +0.8
CAPE... +22.3  CIN... -70.6                | CAPE... +2.4  CIN... -10.6
                                           |
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 -63.4 -82.1  265  31 16   0.9   0.5 | -64.1 -83.4  260  35 18   1.6   0.9
 45000 -60.3 -76.5  260  39 20   4.5   2.5 | -60.4 -76.7  260  42 22   4.3   2.4
 40000 -53.4 -64.1  260  42 22   5.7   3.1 | -53.6 -64.5  255  43 22   6.1   3.4
 38000 -49.9 -57.8  260  38 20   5.7   3.1 | -49.9 -57.8  255  39 20   6.2   3.4
 36000 -46.5 -51.7  255  34 18   5.6   3.1 | -46.2 -51.2  255  36 18   6.1   3.3
 34000 -42.1 -43.8  255  34 17   7.6   4.2 | -41.7 -43.1  260  35 18   7.7   4.2
 32000 -37.0 -34.6  255  34 17   7.7   4.2 | -37.1 -34.8  265  34 18   7.6   4.2
 30000 -32.3 -26.1  260  30 15   7.9   4.3 | -31.8 -25.2  265  30 16   7.9   4.4
 29000 -29.9 -21.8  260  28 14   7.9   4.3 | -29.4 -20.9  265  28 14   8.0   4.4
 28000 -27.6 -17.7  260  25 13   7.0   3.8 | -27.1 -16.8  265  26 13   6.9   3.8
 27000 -25.6 -14.1  260  22 11   6.9   3.8 | -25.0 -13.0  265  23 12   6.8   3.7
 26000 -23.5 -10.3  260  18 10   7.0   3.8 | -23.0  -9.4  265  21 11   6.8   3.7
 25000 -21.5  -6.7  260  15  8   7.3   4.0 | -21.0  -5.8  260  18  9   6.9   3.8
 24000 -19.2  -2.6  260  13  7   7.7   4.2 | -18.8  -1.8  260  17  9   7.3   4.0
 23000 -16.9   1.6  255  12  6   7.7   4.2 | -16.6   2.1  260  16  8   7.4   4.1
 22000 -14.6   5.7  255  10  5   7.5   4.1 | -14.5   5.9  255  15  7   7.5   4.1
 21000 -12.4   9.7  250  13  6   7.4   4.0 | -12.3   9.9  250  17  9   7.5   4.1
 20000 -10.3  13.5  245  15  8   7.4   4.1 | -10.1  13.8  250  19 10   7.6   4.2
 19500  -9.2  15.4  240  16  8   7.4   4.1 |  -9.0  15.8  250  21 11   7.6   4.2
 19000  -8.0  17.6  240  17  9   9.1   5.0 |  -7.9  17.8  250  21 11   8.5   4.7
 18500  -6.7  19.9  240  17  9   9.0   4.9 |  -6.6  20.1  245  21 11   8.5   4.7
 18000  -5.4  22.3  245  17  9   8.3   4.6 |  -5.4  22.3  245  21 11   8.5   4.6
 17500  -4.3  24.3  245  17  9   7.8   4.3 |  -4.2  24.4  245  20 10   8.4   4.6
 17000  -3.2  26.2  245  16  8   7.8   4.3 |  -3.0  26.6  250  19 10   8.4   4.6
 16500  -2.0  28.4  250  16  8   8.1   4.5 |  -1.7  28.9  250  18  9   9.2   5.0
 16000  -0.8  30.6  250  15  8   8.1   4.4 |  -0.3  31.5  250  17  9   9.1   5.0
 15500   0.4  32.7  250  15  8   8.5   4.7 |   1.0  33.8  250  16  8   8.9   4.9
 15000   2.3  36.1  255  15  7   8.6   4.7 |   2.3  36.1  250  16  8   8.9   4.9
 14500   3.6  38.5  255  14  7   8.8   4.8 |   4.3  39.7  255  15  8   8.7   4.8
 14000   5.0  41.0  255  14  7   8.8   4.8 |   5.6  42.1  260  14  7   8.7   4.8
 13500   6.3  43.3  260  14  7   8.9   4.9 |   7.0  44.6  260  14  7   8.7   4.8
 13000   7.6  45.7  260  13  7   8.9   4.9 |   8.3  46.9  265  13  7   8.8   4.8
 12500   8.9  48.0  260  12  6   9.0   4.9 |   9.6  49.3  265  12  6   8.7   4.8
 12000  10.3  50.5  265  11  6   9.0   4.9 |  10.9  51.6  270  12  6   8.7   4.8
 11500  11.7  53.1  265  10  5   8.8   4.8 |  12.2  54.0  275  11  6   8.5   4.7
 11000  12.9  55.2  265   9  5   8.4   4.6 |  13.5  56.3  275  11  6   8.1   4.5
 10500  14.2  57.6  265   8  4   5.4   2.9 |  14.7  58.5  280  11  5   5.6   3.1
 10250  14.5  58.1  265   8  4   7.0   3.8 |  15.0  59.0  285  10  5   6.6   3.6
 10000  15.3  59.5  265   8  4  12.0   6.6 |  15.8  60.4  285  10  5  10.6   5.8
  9750  16.1  61.0  265   8  4  11.4   6.3 |  16.5  61.7  290  10  5  10.1   5.5
  9500  16.9  62.4  260   7  4   8.2   4.5 |  17.3  63.1  290  10  5   8.1   4.5
  9250  17.4  63.3  260   7  4   7.6   4.2 |  17.8  64.0  295   9  5   7.1   3.9
  9000  18.2  64.8  260   7  4  11.0   6.0 |  18.4  65.1  295   9  4   8.8   4.8
  8750  18.9  66.0  260   7  4  10.4   5.7 |  19.0  66.2  295   8  4   8.3   4.6
  8500  19.7  67.5  260   7  4  10.4   5.7 |  19.6  67.3  300   8  4   9.4   5.2
  8250  20.5  68.9  260   7  4  10.1   5.5 |  20.4  68.7  300   8  4  10.1   5.6
  8000  21.2  70.2  260   7  4   9.1   5.0 |  21.1  70.0  295   8  4   9.2   5.1
  7750  21.9  71.4  260   7  4   8.9   4.9 |  21.7  71.1  295   8  4   8.9   4.9
  7500  22.6  72.7  260   7  4  10.3   5.6 |  22.4  72.3  295   8  4   9.7   5.3
  7250  23.4  74.1  255   7  4  11.2   6.2 |  23.2  73.8  295   8  4  10.0   5.5
  7000  24.2  75.6  255   7  4   9.7   5.3 |  23.9  75.0  295   8  4  10.2   5.6
  6750  24.9  76.8  255   7  4   9.6   5.3 |  24.7  76.5  295   8  4  10.6   5.8
  6500  25.7  78.3  255   7  3  11.4   6.2 |  25.5  77.9  295   8  4  10.5   5.8
  6250  26.5  79.7  255   7  3  12.2   6.7 |  26.3  79.3  295   7  4  10.6   5.8
  6000  27.4  81.3  255   7  3   9.5   5.2 |  27.1  80.8  295   7  4  10.4   5.7
  5750  28.1  82.6  255   6  3  12.1   6.7 |  27.8  82.0  295   7  4  10.2   5.6
  5500  29.3  84.7  255   6  3  17.7   9.7 |  28.6  83.5  295   7  4  10.3   5.7
  5250  30.5  86.9  255   6  3  13.3   7.3 |  29.4  84.9  295   7  4  10.2   5.6
  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 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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