Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 311234
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0634 MDT Sunday, August 31, 2014

This forecast is for Sunday, August 31, 2014:

If the trigger temperature of 81.8 F/27.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 590 ft/min (3.0 m/s)
   Maximum height of thermals.................. 15561 ft MSL (10276 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1200 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7448 ft MSL (2163 ft AGL)
Thermal soaring outlook for Monday 09/01....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 17608 ft MSL (12323 ft AGL)
Wave soaring outlook for Monday 09/01.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:26:34 / 19:33:35 MDT
Total possible sunshine........... 13 hr 7 min 1 sec (787 min 1 sec)
Altitude of sun at 12:59:38 MDT... 58.69 degrees

Upper air data from rawinsonde observation taken on 08/31/2014 at 0600 MDT

Freezing level.................. 14881 ft MSL (9596 ft AGL)
Convective condensation level... 16617 ft MSL (11332 ft AGL)
Lifted condensation level....... 16500 ft MSL (11215 ft AGL)
Lifted index.................... +0.6
K index......................... +21.4

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  -61.5 -78.7   265   44   23   1.2   0.7   90.7 195.2    35.9      M    M
 45000  -57.2 -71.0   255   64   33  -0.0  -0.0   73.6 164.4    27.9      M    M
 40000  -53.8 -64.8   265   72   37   4.7   2.6   56.0 132.9    18.1      M    M
 38000  -54.2 -65.6   260   69   36   3.6   2.0   46.7 116.1    12.2      M    M
 36000  -49.9 -57.8   255   67   34   8.5   4.7   44.4 112.0    10.9      M    M
 34000  -44.6 -48.3   255   62   32   9.0   4.9   43.7 110.7    10.7      M    M
 32000  -38.6 -37.5   260   54   28   8.7   4.8   43.1 109.6    10.5      M    M
 30000  -33.6 -28.5   265   48   25   8.3   4.5   42.1 107.7    10.0      M    M
 29000  -31.1 -24.0   260   45   23   8.3   4.5   41.4 106.5     9.5      M    M
 28000  -28.6 -19.5   255   43   22   8.3   4.6   40.8 105.5     9.2      M    M
 27000  -26.2 -15.2   250   41   21   8.4   4.6   40.3 104.6     8.9      M    M
 26000  -23.7 -10.7   250   40   21   7.7   4.2   39.8 103.6     8.6      M    M
 25000  -21.3  -6.3   255   39   20   9.1   5.0   39.1 102.4     8.1      M    M
 24000  -18.8  -1.8   255   39   20   6.6   3.6   38.6 101.5     7.8      M    M
 23000  -16.8   1.8   255   40   20   6.7   3.7   37.5  99.6     6.9      M    M
 22000  -14.7   5.5   255   41   21  -0.6  -0.3   36.5  97.8     6.2      M    M
 21000  -13.3   8.1   265   41   21   4.2   2.3   34.6  94.3     4.7      M    M
 20000  -12.2  10.0   275   42   22   4.7   2.6   32.6  90.7     2.9      M    M
 19500  -11.5  11.3   275   41   21   7.8   4.3   31.9  89.4     2.2      M    M
 19000  -10.1  13.8   270   40   21   9.1   5.0   31.8  89.3     2.1      M    M
 18500   -8.7  16.3   270   41   21   8.8   4.8   31.7  89.0     2.0      M    M
 18000   -7.5  18.5   270   41   21   8.1   4.5   31.4  88.6     1.8      M    M
 17500   -6.3  20.7   265   42   22   8.4   4.6   31.1  88.1     1.5      M    M
 17000   -5.4  22.3   265   43   22   3.4   1.9   30.6  87.1     1.0      M    M
 16500   -4.5  23.9   265   40   20   9.3   5.1   30.0  86.0     0.4      M    M
 16000   -2.6  27.3   260   33   17   8.6   4.7   29.7  85.5     0.1      M    M
 15500   -1.3  29.7   260   31   16   8.6   4.7   29.5  85.2    -0.1    972  4.9
 15000   -0.0  32.0   255   29   15   8.6   4.7   29.3  84.8    -0.3    919  4.7
 14500    1.3  34.3   255   27   14   9.3   5.1   29.2  84.6    -0.4    865  4.4
 14000    2.7  36.9   250   25   13   9.5   5.2   29.2  84.5    -0.4    807  4.1
 13500    4.1  39.4   245   24   12   9.5   5.2   29.1  84.4    -0.5    750  3.8
 13000    5.5  41.9   245   23   12   9.5   5.2   29.1  84.3    -0.5    692  3.5
 12500    7.0  44.6   240   22   11   9.5   5.2   29.0  84.3    -0.5    635  3.2
 12000    8.4  47.1   235   21   11   9.5   5.2   29.0  84.3    -0.6    577  2.9
 11500    9.8  49.6   230   20   10   9.5   5.2   29.0  84.1    -0.6    520  2.6
 11000   11.2  52.2   230   19   10   9.5   5.2   28.9  84.1    -0.7    462  2.3
 10500   12.6  54.7   220   19   10   8.5   4.7   28.8  83.8    -0.8    407  2.1
 10250   13.3  55.9   215   19   10   8.7   4.8   28.7  83.7    -0.9    379  1.9
 10000   13.9  57.0   215   19   10   8.8   4.8   28.6  83.5    -0.9    353  1.8
  9750   14.5  58.1   215   19   10   8.8   4.8   28.5  83.4    -1.0    326  1.7
  9500   15.2  59.4   210   20   10   8.8   4.8   28.5  83.2    -1.1    299  1.5
  9250   15.8  60.4   210   20   10   8.8   4.8   28.4  83.1    -1.2    272  1.4
  9000   16.5  61.7   210   20   10   8.8   4.8   28.3  83.0    -1.3    246  1.2
  8750   17.1  62.8   210   22   11   8.9   4.9   28.3  82.9    -1.4    219  1.1
  8500   17.8  64.0   205   23   12   8.7   4.8   28.2  82.7    -1.5    192  1.0
  8250   18.4  65.1   205   25   13   9.4   5.1   28.1  82.6    -1.6    166  0.8
  8000   19.0  66.2   205   26   13   5.3   2.9   28.0  82.4    -1.7    140  0.7
  7750   19.2  66.6   205   27   14   1.6   0.9   27.4  81.4    -2.3    128  0.7
  7500   19.3  66.7   205   27   14   2.5   1.4   26.9  80.3    -2.9    116  0.6
  7250   19.5  67.1   205   28   15   2.5   1.4   26.3  79.3    -3.4    104  0.5
  7000   19.6  67.3   205   29   15   1.5   0.8   25.7  78.3    -4.0     92  0.5
  6750   19.8  67.6   205   25   13   5.6   3.1   25.2  77.3    -4.6     80  0.4
  6500   19.9  67.8   210   22   11  -9.7  -5.3   24.6  76.3    -5.2     68  0.3
  6250   18.5  65.3   210   18    9 -15.2  -8.3   22.5  72.5    -7.4    104  0.5
  6000   18.0  64.4   215   14    7  -2.1  -1.2   21.3  70.3    -8.7    112  0.6
  5750   17.7  63.9   215   11    5  -0.7  -0.4   20.4  68.7    -9.7    112  0.6
  5500   17.5  63.5   215    7    3  -9.2  -5.0   19.5  67.1   -10.7    112  0.6

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

           08/31/2014 at 0900 MDT          |       08/31/2014 at 1200 MDT
                                           |
K index... +21.0  LI... -0.6               | K index... +25.3  LI... -2.3
CAPE... +21.1  CIN... -259.5               | CAPE... +582.6  CIN... -62.1
                                           |
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 -60.2 -76.4  260  36 18   2.8   1.6 | -60.4 -76.7  265  39 20   2.4   1.3
 45000 -56.5 -69.7  260  59 30   1.2   0.6 | -57.0 -70.6  265  62 32   1.5   0.8
 40000 -54.7 -66.5  270  79 41   2.7   1.5 | -54.7 -66.5  265  73 38   2.8   1.6
 38000 -52.2 -62.0  265  73 38   4.2   2.3 | -51.9 -61.4  270  69 36   4.7   2.6
 36000 -49.7 -57.5  260  67 34   4.1   2.3 | -49.1 -56.4  270  65 34   4.7   2.6
 34000 -45.6 -50.1  260  62 32   8.6   4.7 | -45.3 -49.5  270  61 31   7.4   4.1
 32000 -39.8 -39.6  260  58 30   8.6   4.7 | -40.3 -40.5  270  55 28   7.4   4.1
 30000 -34.4 -29.9  255  50 26   9.2   5.0 | -35.5 -31.9  270  49 25   8.3   4.6
 29000 -31.7 -25.1  250  45 23   9.2   5.1 | -33.0 -27.4  270  46 24   8.3   4.6
 28000 -28.9 -20.0  245  41 21   9.5   5.2 | -30.6 -23.1  265  44 22   8.3   4.6
 27000 -26.8 -16.2  245  37 19   6.3   3.5 | -28.1 -18.6  265  43 22   8.4   4.6
 26000 -25.0 -13.0  250  34 18   6.4   3.5 | -25.5 -13.9  265  44 22   8.4   4.6
 25000 -23.1  -9.6  255  32 16   6.4   3.5 | -23.0  -9.4  260  44 23   8.4   4.6
 24000 -21.1  -6.0  260  31 16   6.6   3.6 | -20.7  -5.3  260  45 23   7.6   4.2
 23000 -19.2  -2.6  265  31 16   6.6   3.6 | -18.4  -1.1  260  46 24   7.6   4.2
 22000 -17.2   1.0  265  32 16   6.6   3.6 | -16.1   3.0  260  48 24   7.7   4.2
 21000 -15.1   4.8  270  32 17   7.4   4.1 | -14.0   6.8  260  49 25   6.9   3.8
 20000 -12.9   8.8  265  33 17   7.4   4.1 | -12.0  10.4  260  50 26   6.9   3.8
 19500 -11.8  10.8  265  33 17   7.5   4.1 | -11.0  12.2  260  51 26   7.0   3.8
 19000 -10.7  12.7  265  33 17   7.8   4.3 | -10.0  14.0  260  52 27   7.3   4.0
 18500  -9.5  14.9  265  33 17   8.4   4.6 |  -8.8  16.2  260  51 26   8.1   4.4
 18000  -8.2  17.2  265  33 17   8.4   4.6 |  -7.7  18.1  260  51 26   8.2   4.5
 17500  -7.0  19.4  265  32 17   8.9   4.9 |  -6.5  20.3  260  50 26   7.1   3.9
 17000  -5.6  21.9  265  31 16   8.9   4.9 |  -5.5  22.1  260  48 25   7.1   3.9
 16500  -4.3  24.3  265  30 16   8.9   4.9 |  -4.5  23.9  260  46 23   7.1   3.9
 16000  -2.4  27.7  260  27 14   8.8   4.8 |  -3.0  26.6  260  40 21   7.2   4.0
 15500  -1.1  30.0  260  24 12   9.0   4.9 |  -1.9  28.6  260  37 19   7.5   4.1
 15000   0.3  32.5  260  22 11   9.0   5.0 |  -0.8  30.6  260  33 17   7.8   4.3
 14500   1.6  34.9  260  20 10   9.0   5.0 |   0.3  32.5  260  29 15   7.9   4.3
 14000   2.9  37.2  265  19 10   9.0   4.9 |   1.5  34.7  260  26 13   8.2   4.5
 13500   4.3  39.7  265  18  9   9.0   4.9 |   2.7  36.9  260  23 12   8.2   4.5
 13000   5.6  42.1  275  21 11   8.6   4.7 |   4.0  39.2  255  21 11   8.5   4.7
 12500   6.9  44.4  280  25 13   8.7   4.8 |   5.2  41.4  255  18  9   8.5   4.7
 12000   8.1  46.6  285  27 14   7.8   4.3 |   6.5  43.7  255  16  8   8.7   4.8
 11500   9.3  48.7  285  27 14   8.0   4.4 |   7.8  46.0  255  14  7   8.8   4.8
 11000  10.4  50.7  290  28 14   7.6   4.2 |   9.0  48.2  260  12  6   7.5   4.1
 10500  11.5  52.7  290  28 14   8.7   4.8 |  10.2  50.4  260  11  5   8.2   4.5
 10250  12.3  54.1  290  28 14  10.1   5.6 |  10.9  51.6  260  10  5  10.9   6.0
 10000  13.0  55.4  290  27 14   8.3   4.6 |  11.7  53.1  265   9  4   9.8   5.4
  9750  13.5  56.3  290  26 13   7.4   4.1 |  12.3  54.1  265   8  4   7.8   4.3
  9500  14.1  57.4  290  25 13   7.8   4.3 |  12.9  55.2  270   7  4   8.6   4.7
  9250  14.6  58.3  295  24 12   7.1   3.9 |  13.5  56.3  275   6  3   7.5   4.1
  9000  15.2  59.4  295  22 12   7.8   4.3 |  14.1  57.4  280   5  3   7.3   4.0
  8750  15.8  60.4  295  21 11   8.9   4.9 |  14.7  58.5  285   5  2   8.0   4.4
  8500  16.4  61.5  295  20 10   8.7   4.7 |  15.2  59.4  295   4  2   7.9   4.3
  8250  17.1  62.8  295  19 10   8.3   4.6 |  15.8  60.4  310   4  2   7.3   4.0
  8000  17.6  63.7  295  18  9   7.2   4.0 |  16.3  61.3  335   4  2   5.6   3.1
  7750  18.1  64.6  295  16  8   6.7   3.7 |  16.7  62.1  355   4  2   4.8   2.6
  7500  18.6  65.5  300  15  8   6.8   3.7 |  17.0  62.6  005   5  3   5.1   2.8
  7250  19.2  66.6  300  14  7   7.6   4.2 |  17.3  63.1  015   6  3   6.4   3.5
  7000  19.7  67.5  305  13  7   7.1   3.9 |  17.7  63.9  025   7  4   7.7   4.2
  6750  20.2  68.4  305  12  6   6.6   3.6 |  18.2  64.8  030   8  4   7.9   4.3
  6500  20.5  68.9  305  10  5   1.9   1.0 |  18.7  65.7  030   9  5   9.4   5.2
  6250  20.3  68.5  305   9  5  -3.8  -2.1 |  19.5  67.1  030   9  5  11.3   6.2
  6000  19.9  67.8  295   7  4  -4.5  -2.5 |  20.3  68.5  030   9  4  11.2   6.1
  5750  19.4  66.9  285   6  3  -6.7  -3.7 |  21.1  70.0  030   9  4  11.4   6.3
  5500  18.7  65.7  260   5  3  -3.9  -2.1 |  22.1  71.8  030   9  4  17.8   9.8

           08/31/2014 at 1500 MDT          |       08/31/2014 at 1800 MDT
                                           |
K index... +27.1  LI... -3.5               | K index... +27.8  LI... -3.5
CAPE... +920.0  CIN... -32.0               | CAPE... +804.2  CIN... -40.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -60.2 -76.4  260  38 20   2.6   1.4 | -59.5 -75.1  280  41 21   2.6   1.4
 45000 -56.2 -69.2  270  63 32   2.2   1.2 | -55.9 -68.6  285  65 34   1.6   0.9
 40000 -53.0 -63.4  280  72 37   2.6   1.4 | -53.6 -64.5  295  79 41   3.1   1.7
 38000 -51.1 -60.0  280  69 36   3.2   1.7 | -50.8 -59.4  300  80 41   4.7   2.6
 36000 -49.1 -56.4  275  67 34   3.2   1.7 | -47.9 -54.2  300  81 42   4.7   2.6
 34000 -45.8 -50.4  275  64 33   7.3   4.0 | -44.4 -47.9  300  78 40   6.7   3.7
 32000 -40.9 -41.6  275  62 32   7.3   4.0 | -39.9 -39.8  295  72 37   6.7   3.7
 30000 -36.1 -33.0  275  60 31   8.3   4.6 | -35.6 -32.1  285  62 32   7.5   4.1
 29000 -33.6 -28.5  275  59 30   8.3   4.6 | -33.3 -27.9  280  57 30   7.5   4.1
 28000 -31.1 -24.0  275  58 30   8.4   4.6 | -31.1 -24.0  275  53 27   7.5   4.1
 27000 -28.7 -19.7  275  58 30   8.0   4.4 | -28.7 -19.7  270  53 27   8.0   4.4
 26000 -26.3 -15.3  275  57 29   8.0   4.4 | -26.4 -15.5  275  53 27   8.0   4.4
 25000 -24.0 -11.2  270  57 29   8.0   4.4 | -24.0 -11.2  275  53 27   8.0   4.4
 24000 -21.6  -6.9  270  57 29   7.6   4.2 | -21.6  -6.9  275  53 27   7.9   4.4
 23000 -19.4  -2.9  270  58 30   7.6   4.2 | -19.2  -2.6  275  52 27   7.9   4.4
 22000 -17.1   1.2  270  59 30   7.6   4.2 | -16.9   1.6  275  52 27   8.0   4.4
 21000 -14.9   5.2  265  59 30   7.4   4.0 | -14.7   5.5  275  51 26   7.1   3.9
 20000 -12.8   9.0  265  59 30   7.4   4.0 | -12.5   9.5  270  51 26   7.1   3.9
 19500 -11.7  10.9  265  59 30   7.4   4.1 | -11.5  11.3  270  51 26   7.2   3.9
 19000 -10.6  12.9  265  58 30   7.4   4.0 | -10.4  13.3  270  50 26   7.3   4.0
 18500  -9.5  14.9  260  57 29   7.3   4.0 |  -9.3  15.3  270  49 25   7.6   4.2
 18000  -8.4  16.9  260  55 28   7.4   4.0 |  -8.2  17.2  270  48 25   7.6   4.2
 17500  -7.4  18.7  260  52 27   7.4   4.1 |  -7.1  19.2  270  46 24   7.9   4.3
 17000  -6.3  20.7  260  49 25   7.5   4.1 |  -6.0  21.2  265  44 23   8.0   4.4
 16500  -5.2  22.6  255  46 24   7.9   4.3 |  -4.8  23.4  265  42 21   8.2   4.5
 16000  -3.4  25.9  255  41 21   8.5   4.6 |  -3.0  26.6  265  38 19   8.6   4.7
 15500  -2.1  28.2  255  38 19   8.5   4.7 |  -1.7  28.9  265  35 18   9.0   4.9
 15000  -0.9  30.4  255  35 18   8.6   4.7 |  -0.4  31.3  265  33 17   9.2   5.0
 14500   0.4  32.7  255  33 17   8.9   4.9 |   1.0  33.8  265  31 16   9.2   5.0
 14000   1.8  35.2  255  31 16   9.6   5.3 |   2.3  36.1  265  29 15   9.1   5.0
 13500   3.2  37.8  255  29 15   9.6   5.3 |   3.7  38.7  265  28 14   9.1   5.0
 13000   4.6  40.3  255  28 14   9.3   5.1 |   5.0  41.0  270  26 13   8.8   4.8
 12500   6.0  42.8  255  26 13   9.4   5.1 |   6.3  43.3  270  23 12   8.8   4.9
 12000   7.3  45.1  255  23 12   8.4   4.6 |   7.6  45.7  270  20 10   8.3   4.5
 11500   8.5  47.3  255  21 11   8.7   4.7 |   8.8  47.8  270  17  9   8.4   4.6
 11000   9.6  49.3  255  18  9   6.7   3.7 |   9.9  49.8  270  14  7   7.1   3.9
 10500  10.6  51.1  250  14  7   8.2   4.5 |  11.0  51.8  265  11  5   8.0   4.4
 10250  11.3  52.3  250  13  7   9.8   5.4 |  11.6  52.9  260   9  4   9.2   5.0
 10000  11.9  53.4  250  11  6   7.5   4.1 |  12.2  54.0  265   7  4   8.0   4.4
  9750  12.4  54.3  255   9  5   6.6   3.6 |  12.7  54.9  270   6  3   7.4   4.0
  9500  12.9  55.2  255   7  4   6.8   3.8 |  13.2  55.8  275   4  2   7.5   4.1
  9250  13.4  56.1  260   5  3   6.8   3.8 |  13.7  56.7  285   3  2   7.9   4.3
  9000  13.8  56.8  275   4  2   7.6   4.2 |  14.3  57.7  295   3  1   9.0   4.9
  8750  14.4  57.9  295   3  1   8.2   4.5 |  15.0  59.0  305   2  1   9.5   5.2
  8500  14.9  58.8  330   3  1   8.0   4.4 |  15.7  60.3  315   2  1   8.9   4.9
  8250  15.5  59.9  355   3  2  10.0   5.5 |  16.4  61.5  330   2  1  11.5   6.3
  8000  16.3  61.3  355   3  2  10.5   5.7 |  17.3  63.1  335   2  1  11.1   6.1
  7750  17.0  62.6  355   3  2   9.1   5.0 |  17.9  64.2  335   2  1   8.3   4.6
  7500  17.7  63.9  355   3  2   9.5   5.2 |  18.6  65.5  340   2  1   9.2   5.0
  7250  18.4  65.1  355   4  2   9.8   5.4 |  19.3  66.7  340   3  1  10.7   5.9
  7000  19.1  66.4  355   4  2  10.0   5.5 |  20.2  68.4  345   2  1  11.0   6.0
  6750  19.9  67.8  355   4  2   9.4   5.2 |  20.9  69.6  345   2  1   8.9   4.9
  6500  20.6  69.1  355   4  2  10.1   5.5 |  21.6  70.9  345   3  1   9.1   5.0
  6250  21.4  70.5  355   4  2  11.3   6.2 |  22.3  72.1  350   3  1  10.3   5.7
  6000  22.2  72.0  355   4  2  11.0   6.1 |  23.1  73.6  350   3  1  10.4   5.7
  5750  23.0  73.4  355   4  2  10.9   6.0 |  23.8  74.8  350   3  1   9.7   5.3
  5500  24.0  75.2  355   4  2  16.3   9.0 |  24.5  76.1  350   3  1  10.6   5.8
________________________________________________________________________________

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 near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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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