Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 011245
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0645 MDT Monday, September 1, 2014

This forecast is for Monday, September 1, 2014:

If the trigger temperature of 75.1 F/23.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1013 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16683 ft MSL (11844 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1030 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................. 11882 ft MSL (7043 ft AGL)
Thermal soaring outlook for Tuesday 09/02...... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:42:51 / 19:45:59 MDT
Total possible sunshine........... 13 hr 3 min 9 sec (783 min 9 sec)
Altitude of sun at 13:13:59 MDT... 58.97 degrees

Upper air data from rawinsonde observation taken on 09/01/2014 at 0600 MDT

Freezing level.................. 14580 ft MSL (9741 ft AGL)
Convective condensation level... 19375 ft MSL (14536 ft AGL)
Lifted condensation level....... 17252 ft MSL (12413 ft AGL)
Lifted index.................... +2.2
K index......................... +13.9

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  -66.8 -88.2   280   57   29   6.2   3.4   83.7 182.7    30.8      M    M
 45000  -59.0 -74.2   280   54   28   5.9   3.2   72.2 162.0    25.8      M    M
 40000  -56.4 -69.5   290   72   37  10.3   5.6   53.4 128.2    15.2      M    M
 38000  -51.0 -59.8   290   69   35   8.9   4.9   52.8 127.0    15.1      M    M
 36000  -46.5 -51.7   290   65   34   5.7   3.1   49.8 121.7    13.5      M    M
 34000  -41.5 -42.7   290   65   33   8.8   4.8   48.5 119.4    13.0      M    M
 32000  -36.5 -33.7   285   65   33   7.3   4.0   47.4 117.3    12.4      M    M
 30000  -32.0 -25.6   280   62   32   9.0   5.0   45.6 114.1    11.4      M    M
 29000  -29.3 -20.7   280   60   31   8.8   4.9   45.1 113.3    11.2      M    M
 28000  -26.7 -16.1   280   58   30   8.8   4.9   44.8 112.6    11.0      M    M
 27000  -24.1 -11.4   275   57   29   7.5   4.1   44.5 112.0    10.9      M    M
 26000  -22.0  -7.6   275   55   28   7.1   3.9   43.4 110.1    10.2      M    M
 25000  -19.8  -3.6   275   53   27   7.0   3.8   42.5 108.5     9.5      M    M
 24000  -18.2  -0.8   275   55   28   4.2   2.3   41.0 105.7     8.4      M    M
 23000  -16.0   3.2   275   56   29   7.7   4.2   40.0 104.1     7.7      M    M
 22000  -13.7   7.3   275   57   29   7.7   4.2   39.4 102.9     7.2      M    M
 21000  -11.5  11.3   275   52   27   7.7   4.2   38.6 101.5     6.6      M    M
 20000   -9.2  15.4   280   48   24   7.7   4.2   37.9 100.2     6.0      M    M
 19500   -8.0  17.6   280   45   23   7.7   4.2   37.5  99.5     5.7      M    M
 19000   -6.4  20.5   275   42   22   5.9   3.2   36.9  98.3     5.2      M    M
 18500   -5.8  21.6   275   42   22  -2.0  -1.1   35.8  96.4     4.4      M    M
 18000   -6.6  20.1   275   42   22  -1.0  -0.5   33.2  91.8     2.1      M    M
 17500   -6.4  20.5   280   43   22   3.2   1.8   32.0  89.7     0.9      M    M
 17000   -5.7  21.7   280   43   22   7.0   3.8   31.2  88.1     0.1      M    M
 16500   -4.5  23.9   280   43   22   8.0   4.4   30.9  87.6    -0.1    986  5.0
 16000   -3.3  26.1   280   43   22   8.1   4.5   30.7  87.2    -0.4    935  4.7
 15500   -2.1  28.2   280   42   22   8.1   4.5   30.4  86.7    -0.6    884  4.5
 15000   -0.9  30.4   280   41   21   8.1   4.5   30.2  86.3    -0.9    834  4.2
 14500    0.3  32.5   280   38   19   8.1   4.5   29.9  85.8    -1.2    783  4.0
 14000    1.5  34.7   280   35   18   8.1   4.5   29.6  85.3    -1.4    732  3.7
 13500    2.7  36.9   275   33   17   8.1   4.5   29.3  84.8    -1.7    681  3.5
 13000    3.9  39.0   270   31   16   8.1   4.4   29.1  84.3    -2.0    631  3.2
 12500    5.1  41.2   275   29   15   7.2   3.9   28.8  83.8    -2.3    580  2.9
 12000    6.0  42.8   280   27   14   5.8   3.2   28.2  82.7    -2.9    538  2.7
 11500    6.9  44.4   280   25   13   5.7   3.2   27.5  81.5    -3.5    498  2.5
 11000    7.7  45.9   285   23   12   5.7   3.1   26.8  80.3    -4.1    457  2.3
 10500    8.6  47.5   290   22   11   5.7   3.1   26.2  79.2    -4.7    416  2.1
 10250    9.0  48.2   290   21   11   6.2   3.4   25.9  78.7    -5.0    396  2.0
 10000    9.5  49.1   295   19   10   6.7   3.7   25.7  78.2    -5.3    374  1.9
  9750   10.0  50.0   295   17    9   6.6   3.6   25.4  77.8    -5.6    353  1.8
  9500   10.5  50.9   300   15    8   6.5   3.6   25.2  77.3    -5.8    331  1.7
  9250   10.9  51.6   305   14    7   7.2   3.9   24.9  76.9    -6.1    309  1.6
  9000   11.5  52.7   310   12    6   8.1   4.4   24.8  76.6    -6.2    284  1.4
  8750   12.1  53.8   310   10    5   8.0   4.4   24.7  76.4    -6.4    259  1.3
  8500   12.7  54.9   310    7    4   8.0   4.4   24.5  76.2    -6.6    234  1.2
  8250   13.3  55.9   310    4    2   8.0   4.4   24.4  75.9    -6.7    209  1.1
  8000   13.9  57.0   305    1    1   8.0   4.4   24.3  75.7    -6.8    184  0.9
  7750   14.5  58.1   310    1    0   8.0   4.4   24.1  75.5    -7.0    159  0.8
  7500   15.1  59.2   320    1    0   8.0   4.4   24.0  75.2    -7.2    133  0.7
  7250   15.7  60.3   330    1    0   8.0   4.4   23.9  75.0    -7.3    108  0.5
  7000   16.3  61.3   345    1    1   8.0   4.4   23.7  74.7    -7.5     83  0.4
  6750   16.8  62.2   340    1    1   8.0   4.4   23.6  74.5    -7.6     58  0.3
  6500   17.4  63.3   330    1    0   8.0   4.4   23.5  74.2    -7.8     33  0.2
  6250   18.0  64.4   320    1    0   7.8   4.3   23.3  74.0    -8.0      8  0.0
  6000   18.6  65.5   310    1    1   8.7   4.8   23.2  73.7    -8.1      M    M
  5750   19.2  66.6   010    1    0   5.1   2.8   23.0  73.5    -8.3      M    M
  5500   19.3  66.7   060    2    1   1.9   1.0   22.5  72.5    -8.9      M    M
  5250   19.5  67.1   075    3    1   2.1   1.1   21.9  71.5    -9.5      M    M
  5000   18.9  66.0   080    4    2 -22.0 -12.1   20.7  69.3   -10.8      M    M

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

           09/01/2014 at 0900 MDT          |       09/01/2014 at 1200 MDT
                                           |
K index... +15.3  LI... +5.4               | K index... +14.4  LI... +4.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -64.5 -84.1  295  48 25   2.3   1.3 | -65.5 -85.9  300  46 24   2.2   1.2
 45000 -60.8 -77.4  300  63 32   2.9   1.6 | -61.6 -78.9  305  59 30   3.9   2.1
 40000 -55.9 -68.6  305  72 37   8.5   4.7 | -55.4 -67.7  310  60 31   8.4   4.6
 38000 -51.0 -59.8  305  71 37   8.1   4.4 | -50.4 -58.7  310  62 32   8.2   4.5
 36000 -46.2 -51.2  300  70 36   8.1   4.4 | -45.5 -49.9  305  64 33   8.2   4.5
 34000 -41.2 -42.2  300  69 35   8.2   4.5 | -40.4 -40.7  305  64 33   7.5   4.1
 32000 -35.7 -32.3  295  68 35   8.2   4.5 | -35.9 -32.6  305  63 32   7.4   4.1
 30000 -31.1 -24.0  290  66 34   7.5   4.1 | -31.1 -24.0  305  61 32   8.0   4.4
 29000 -28.8 -19.8  290  64 33   7.5   4.1 | -28.7 -19.7  305  61 31   8.0   4.4
 28000 -26.6 -15.9  290  63 33   7.4   4.1 | -26.3 -15.3  305  60 31   8.0   4.4
 27000 -24.4 -11.9  290  62 32   7.3   4.0 | -23.9 -11.0  300  59 30   7.9   4.3
 26000 -22.2  -8.0  290  61 32   7.3   4.0 | -21.5  -6.7  300  58 30   7.9   4.3
 25000 -20.0  -4.0  290  60 31   7.3   4.0 | -19.2  -2.6  295  58 30   7.9   4.3
 24000 -17.7   0.1  290  59 30   8.1   4.4 | -16.8   1.8  295  56 29   7.8   4.3
 23000 -15.3   4.5  290  57 29   8.1   4.5 | -14.5   5.9  295  54 28   7.8   4.3
 22000 -12.8   9.0  290  55 28   8.3   4.6 | -12.2  10.0  295  52 27   7.9   4.4
 21000 -10.7  12.7  290  54 28   7.0   3.8 | -10.2  13.6  290  51 26   6.1   3.3
 20000  -8.6  16.5  285  52 27   7.0   3.8 |  -8.4  16.9  290  51 26   6.1   3.4
 19500  -7.6  18.3  285  51 26   7.0   3.8 |  -7.5  18.5  290  50 26   6.2   3.4
 19000  -6.6  20.1  285  50 26   6.1   3.3 |  -6.7  19.9  285  50 26   4.1   2.3
 18500  -5.8  21.6  285  49 25   5.5   3.0 |  -6.2  20.8  290  48 25   3.4   1.9
 18000  -5.0  23.0  285  47 24   5.7   3.1 |  -5.8  21.6  290  46 24   3.6   2.0
 17500  -4.3  24.3  285  46 24   3.0   1.7 |  -5.1  22.8  290  44 23   5.6   3.1
 17000  -3.8  25.2  280  44 23   3.3   1.8 |  -4.3  24.3  290  42 22   5.5   3.0
 16500  -3.4  25.9  280  42 22   3.3   1.8 |  -3.5  25.7  290  40 20   4.6   2.5
 16000  -2.9  26.8  280  41 21   3.3   1.8 |  -2.6  27.3  285  37 19   4.2   2.3
 15500  -2.1  28.2  280  38 20   6.1   3.3 |  -1.9  28.6  285  35 18   5.4   3.0
 15000  -1.2  29.8  280  36 19   6.6   3.6 |  -1.1  30.0  280  33 17   5.6   3.1
 14500  -0.3  31.5  275  34 18   7.0   3.8 |  -0.3  31.5  280  32 16   6.9   3.8
 14000   0.8  33.4  275  31 16   7.3   4.0 |   0.8  33.4  275  29 15   7.6   4.2
 13500   1.9  35.4  275  28 15   7.4   4.1 |   1.9  35.4  275  27 14   7.9   4.3
 13000   3.0  37.4  275  26 13   7.9   4.3 |   3.1  37.6  270  26 13   8.3   4.5
 12500   4.1  39.4  270  24 12   7.9   4.3 |   4.3  39.7  270  24 12   8.4   4.6
 12000   5.3  41.5  270  22 11   7.9   4.4 |   5.6  42.1  270  22 11   9.0   4.9
 11500   6.5  43.7  270  19 10   7.9   4.3 |   6.9  44.4  270  21 11   8.7   4.8
 11000   7.7  45.9  270  17  9   7.5   4.1 |   8.1  46.6  270  19 10   7.3   4.0
 10500   8.8  47.8  265  15  8   4.8   2.6 |   9.2  48.6  270  17  9   4.4   2.4
 10250   9.0  48.2  265  14  7   5.0   2.8 |   9.4  48.9  270  17  9   5.2   2.9
 10000   9.6  49.3  265  13  7   8.9   4.9 |  10.1  50.2  270  16  8   9.8   5.4
  9750  10.2  50.4  260  12  6   8.0   4.4 |  10.8  51.4  270  15  8   8.9   4.9
  9500  10.8  51.4  260  11  6   7.7   4.2 |  11.4  52.5  270  14  7   8.0   4.4
  9250  11.3  52.3  260  10  5   6.2   3.4 |  11.9  53.4  275  13  7   6.1   3.3
  9000  11.8  53.2  255   8  4   6.0   3.3 |  12.4  54.3  275  12  6   6.6   3.6
  8750  12.2  54.0  255   7  4   6.6   3.6 |  12.9  55.2  275  11  5   7.2   3.9
  8500  12.7  54.9  250   6  3   6.3   3.4 |  13.4  56.1  275   9  5   6.6   3.6
  8250  13.2  55.8  245   5  3   6.1   3.3 |  13.9  57.0  280   8  4   5.9   3.2
  8000  13.6  56.5  240   5  2   5.9   3.2 |  14.3  57.7  280   6  3   6.4   3.5
  7750  14.1  57.4  225   4  2   5.8   3.2 |  14.8  58.6  280   5  3   6.7   3.7
  7500  14.5  58.1  215   4  2   5.7   3.1 |  15.3  59.5  285   4  2   8.1   4.5
  7250  14.9  58.8  205   4  2   5.8   3.2 |  16.0  60.8  285   4  2   9.4   5.2
  7000  15.3  59.5  195   5  3   5.2   2.9 |  16.6  61.9  285   3  2   9.1   5.0
  6750  15.6  60.1  185   5  3   3.4   1.9 |  17.3  63.1  285   3  2   9.9   5.4
  6500  15.8  60.4  180   5  3   1.2   0.6 |  18.1  64.6  285   3  2  10.7   5.9
  6250  15.8  60.4  170   5  3   0.9   0.5 |  18.9  66.0  285   3  2  11.2   6.2
  6000  15.9  60.6  160   5  3  -0.8  -0.4 |  19.7  67.5  285   3  2  10.1   5.6
  5750  15.8  60.4  145   4  2   2.7   1.5 |  20.5  68.9  285   3  2  12.1   6.6
  5500  16.3  61.3  145   4  2   8.7   4.8 |  21.6  70.9  285   3  2  15.1   8.3
  5250  16.8  62.2  140   4  2   5.0   2.7 |  22.6  72.7  285   3  2  12.7   7.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/01/2014 at 1500 MDT          |       09/01/2014 at 1800 MDT
                                           |
K index... +8.8  LI... +4.5                | K index... +13.5  LI... +4.6
CAPE... 0.0  CIN... M                      | 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 -65.8 -86.4  300  34 18   2.1   1.1 | -66.2 -87.2  295  32 17   2.4   1.3
 45000 -61.8 -79.2  295  50 26   4.3   2.4 | -61.8 -79.2  295  45 23   4.3   2.4
 40000 -54.4 -65.9  290  55 28   7.7   4.2 | -54.5 -66.1  285  55 28   7.3   4.0
 38000 -49.8 -57.6  295  56 29   7.8   4.3 | -50.1 -58.2  290  56 29   7.4   4.1
 36000 -45.1 -49.2  300  57 29   7.7   4.2 | -45.6 -50.1  290  56 29   7.2   4.0
 34000 -40.3 -40.5  300  57 29   8.2   4.5 | -40.6 -41.1  295  55 28   8.6   4.7
 32000 -35.4 -31.7  300  57 29   8.2   4.5 | -35.5 -31.9  295  54 28   8.5   4.7
 30000 -31.0 -23.8  300  54 28   7.1   3.9 | -30.7 -23.3  300  51 26   7.8   4.3
 29000 -28.8 -19.8  300  53 27   7.1   3.9 | -28.4 -19.1  300  49 25   7.8   4.3
 28000 -26.7 -16.1  300  51 26   7.4   4.1 | -26.1 -15.0  300  47 24   7.7   4.2
 27000 -23.7 -10.7  300  50 26   8.1   4.5 | -23.3  -9.9  295  45 23   7.4   4.1
 26000 -21.3  -6.3  300  50 26   8.1   4.5 | -21.1  -6.0  295  42 22   7.5   4.1
 25000 -18.8  -1.8  300  49 25   8.0   4.4 | -18.9  -2.0  295  40 21   7.5   4.1
 24000 -16.6   2.1  300  48 25   7.6   4.2 | -16.6   2.1  295  39 20   7.6   4.2
 23000 -14.3   6.3  295  47 24   7.7   4.2 | -14.3   6.3  295  39 20   7.7   4.2
 22000 -12.0  10.4  295  45 23   7.4   4.1 | -12.1  10.2  295  38 20   7.6   4.2
 21000  -9.9  14.2  295  44 23   6.8   3.7 |  -9.9  14.2  295  37 19   7.3   4.0
 20000  -7.9  17.8  295  43 22   6.8   3.7 |  -7.6  18.3  295  35 18   7.3   4.0
 19500  -6.8  19.8  295  43 22   6.9   3.8 |  -6.5  20.3  295  35 18   7.3   4.0
 19000  -5.8  21.6  295  42 22   6.4   3.5 |  -5.4  22.3  295  34 18   7.2   3.9
 18500  -4.9  23.2  295  42 22   6.4   3.5 |  -4.3  24.3  300  34 17   7.2   3.9
 18000  -3.9  25.0  295  42 22   5.7   3.1 |  -3.2  26.2  300  33 17   6.5   3.6
 17500  -3.4  25.9  295  41 21   3.4   1.9 |  -2.5  27.5  300  33 17   4.8   2.6
 17000  -2.9  26.8  295  39 20   3.6   2.0 |  -1.8  28.8  300  34 17   5.1   2.8
 16500  -2.3  27.9  295  38 19   6.0   3.3 |  -1.2  29.8  300  33 17   2.8   1.6
 16000  -1.4  29.5  295  35 18   6.1   3.3 |  -0.9  30.4  300  32 16   3.1   1.7
 15500  -0.5  31.1  295  33 17   6.1   3.4 |  -0.5  31.1  300  31 16   4.6   2.5
 15000   0.4  32.7  295  31 16   6.2   3.4 |   0.3  32.5  300  27 14   5.7   3.1
 14500   1.3  34.3  295  28 15   6.2   3.4 |   1.0  33.8  295  23 12   6.2   3.4
 14000   2.2  36.0  290  26 13   6.2   3.4 |   2.1  35.8  295  20 10   8.2   4.5
 13500   3.1  37.6  285  24 12   6.1   3.3 |   3.2  37.8  290  17  9   8.1   4.5
 13000   4.6  40.3  275  22 11   7.5   4.1 |   5.1  41.2  285  14  7   8.5   4.7
 12500   5.7  42.3  270  21 11   7.9   4.3 |   6.3  43.3  280  13  7   8.7   4.8
 12000   6.9  44.4  270  21 11   8.6   4.7 |   7.7  45.9  275  12  6   9.0   4.9
 11500   8.2  46.8  265  21 11   8.7   4.8 |   9.0  48.2  270  12  6   8.9   4.9
 11000   9.5  49.1  265  20 10   8.8   4.8 |  10.3  50.5  270  11  6   8.3   4.6
 10500  10.8  51.4  265  20 10   5.2   2.9 |  11.6  52.9  265  11  6   5.5   3.0
 10250  11.0  51.8  265  19 10   5.5   3.0 |  11.9  53.4  265  11  6   6.6   3.6
 10000  11.7  53.1  265  19 10  10.5   5.8 |  12.6  54.7  265  11  6  11.1   6.1
  9750  12.4  54.3  265  18  9   9.5   5.2 |  13.4  56.1  265  12  6  10.3   5.6
  9500  13.1  55.6  270  17  9   8.4   4.6 |  14.2  57.6  265  12  6   9.1   5.0
  9250  13.6  56.5  270  16  8   6.6   3.6 |  14.7  58.5  265  12  6   7.8   4.3
  9000  14.1  57.4  270  15  8   7.3   4.0 |  15.4  59.7  270  12  6   8.6   4.7
  8750  14.6  58.3  275  13  7   7.3   4.0 |  16.0  60.8  270  12  6   9.0   4.9
  8500  15.1  59.2  280  12  6   7.6   4.2 |  16.7  62.1  270  12  6   8.0   4.4
  8250  15.7  60.3  280  10  5   8.0   4.4 |  17.2  63.0  270  11  6   6.8   3.7
  8000  16.3  61.3  280   9  5   8.8   4.8 |  17.7  63.9  275  10  5   7.2   3.9
  7750  17.0  62.6  280   9  5   9.3   5.1 |  18.2  64.8  275   9  5   7.3   4.0
  7500  17.6  63.7  285   8  4   9.8   5.4 |  18.8  65.8  280   8  4   8.2   4.5
  7250  18.4  65.1  285   8  4  10.6   5.8 |  19.4  66.9  280   7  4   9.0   5.0
  7000  19.2  66.6  285   8  4   9.8   5.4 |  20.1  68.2  280   7  4   8.8   4.8
  6750  19.9  67.8  285   8  4   9.7   5.3 |  20.7  69.3  280   7  3   9.3   5.1
  6500  20.7  69.3  285   8  4  10.7   5.9 |  21.4  70.5  280   7  3  10.2   5.6
  6250  21.5  70.7  280   8  4  11.6   6.4 |  22.2  72.0  280   6  3  10.9   6.0
  6000  22.3  72.1  280   8  4  10.0   5.5 |  23.0  73.4  280   6  3   9.9   5.4
  5750  23.0  73.4  285   7  4  11.5   6.3 |  23.7  74.7  280   6  3   8.8   4.8
  5500  24.0  75.2  285   7  4  15.0   8.2 |  24.3  75.7  280   6  3   9.1   5.0
  5250  25.1  77.2  285   7  4  12.8   7.0 |  25.0  77.0  285   6  3   9.2   5.0
  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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