Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 231234
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0634 MDT Saturday, May 23, 2015

This forecast is for Saturday, May 23, 2015:

If the trigger temperature of 61.0 F/16.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 76 ft/min (0.4 m/s)
   Maximum height of thermals.................. 9395 ft MSL (4110 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... 1400 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8427 ft MSL (3141 ft AGL)
Thermal soaring outlook for Sunday 05/24....... Good

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)................ Neither
Potential height of wave....................... 39451 ft MSL (34166 ft AGL)
Wave soaring outlook for Sunday 05/24.......... Poor

Remarks...

Sunrise/Sunset.................... 05:38:44 / 20:13:32 MDT
Total possible sunshine........... 14 hr 34 min 49 sec (874 min 49 sec)
Altitude of sun at 12:56:20 MDT... 70.84 degrees

Upper air data from rawinsonde observation taken on 05/23/2015 at 0600 MDT

Freezing level.................. 11562 ft MSL (6277 ft AGL)
Convective condensation level... 11134 ft MSL (5849 ft AGL)
Lifted condensation level....... 10458 ft MSL (5173 ft AGL)
Lifted index.................... -2.7
K index......................... +24.4

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  -58.4 -73.1   215   21   11   4.7   2.6  101.0 213.7    48.4      M    M
 45000  -54.9 -66.8   240   46   24 -20.9 -11.5   82.5 180.6    40.4      M    M
 40000  -61.1 -78.0   195  109   56   7.2   4.0   48.6 119.6    21.1      M    M
 38000  -56.6 -69.9   195  109   56   7.2   4.0   46.5 115.8    20.2      M    M
 36000  -51.6 -60.9   200  106   55   4.3   2.4   45.4 113.8    20.0      M    M
 34000  -48.1 -54.6   205  104   54   7.9   4.3   42.1 107.7    18.2      M    M
 32000  -45.3 -49.5   210   95   49   3.9   2.1   37.8 100.0    15.5      M    M
 30000  -41.7 -43.1   210   82   42   8.0   4.4   34.8  94.7    13.6      M    M
 29000  -38.6 -37.5   210   75   39   8.3   4.6   34.0  93.2    13.2      M    M
 28000  -36.2 -33.2   210   69   36   8.0   4.4   33.5  92.3    13.0      M    M
 27000  -33.9 -29.0   215   63   33   7.6   4.2   32.6  90.7    12.4      M    M
 26000  -31.9 -25.4   215   58   30   0.8   0.4   31.5  88.6    11.7      M    M
 25000  -31.4 -24.5   215   52   27   4.0   2.2   28.4  83.1     9.4      M    M
 24000  -29.3 -20.7   220   45   23   8.6   4.7   27.4  81.4     8.7      M    M
 23000  -26.7 -16.1   220   44   22   9.1   5.0   27.1  80.7     8.5      M    M
 22000  -23.9 -11.0   220   42   22   9.2   5.0   26.8  80.3     8.4      M    M
 21000  -21.1  -6.0   215   41   21   9.7   5.3   26.7  80.1     8.4      M    M
 20000  -18.3  -0.9   215   40   21   7.7   4.2   26.7  80.1     8.4      M    M
 19500  -17.4   0.7   215   39   20   6.1   3.4   26.0  78.9     7.9      M    M
 19000  -16.5   2.3   215   38   19   6.1   3.4   25.4  77.7     7.3      M    M
 18500  -15.5   4.1   215   36   19   7.5   4.1   24.9  76.8     7.0      M    M
 18000  -14.3   6.3   215   35   18   5.8   3.2   24.6  76.2     6.7      M    M
 17500  -13.7   7.3   215   33   17   7.5   4.1   23.7  74.7     5.9      M    M
 17000  -12.4   9.7   220   31   16   8.6   4.7   23.5  74.3     5.8      M    M
 16500  -11.1  12.0   220   29   15   8.7   4.7   23.3  74.0     5.6      M    M
 16000   -9.9  14.2   220   27   14   8.7   4.8   23.1  73.7     5.4      M    M
 15500   -8.6  16.5   220   26   13   8.6   4.7   23.0  73.3     5.3      M    M
 15000   -7.3  18.9   215   24   12   8.6   4.7   22.7  72.9     5.1      M    M
 14500   -5.4  22.3   210   21   11   8.7   4.8   22.5  72.5     4.9      M    M
 14000   -4.4  24.1   210   20   10   5.4   3.0   22.0  71.6     4.4      M    M
 13500   -3.6  25.5   210   19   10   5.8   3.2   21.3  70.4     3.8      M    M
 13000   -2.8  27.0   210   18    9   5.8   3.2   20.7  69.3     3.2      M    M
 12500   -1.9  28.6   205   17    9   7.6   4.2   20.2  68.4     2.7      M    M
 12000   -0.8  30.6   205   16    8   7.4   4.1   19.9  67.8     2.3      M    M
 11500    0.3  32.5   210   15    8   7.4   4.1   19.5  67.0     1.9      M    M
 11000    1.4  34.5   215   14    7   7.4   4.1   19.1  66.4     1.5      M    M
 10500    2.4  36.3   220   13    6   7.2   4.0   18.7  65.7     1.2      M    M
 10250    3.0  37.4   225   12    6   8.3   4.5   18.6  65.4     1.0      M    M
 10000    3.6  38.5   225   11    6   6.8   3.7   18.5  65.2     0.9      M    M
  9750    4.0  39.2   230    9    5   6.8   3.7   18.2  64.7     0.6      M    M
  9500    4.5  40.1   240    8    4   0.7   0.4   17.8  64.1     0.3      M    M
  9250    4.0  39.2   245    6    3  -6.5  -3.5   16.7  62.1    -0.8    280  1.4
  9000    3.7  38.7   260    5    2   0.8   0.4   15.7  60.2    -1.9    283  1.4
  8750    3.9  39.0   255    2    1   4.7   2.6   15.2  59.4    -2.4    268  1.4
  8500    4.2  39.6   000    0    0   3.8   2.1   14.8  58.6    -2.9    254  1.3
  8250    4.4  39.9   095    3    1   3.5   1.9   14.3  57.8    -3.4    239  1.2
  8000    4.6  40.3   090    5    3   3.3   1.8   13.8  56.9    -3.9    225  1.1
  7750    5.0  41.0   095    4    2   5.8   3.2   13.4  56.2    -4.3    208  1.1
  7500    5.5  41.9   105    3    2   7.1   3.9   13.2  55.7    -4.5    185  0.9
  7250    6.0  42.8   115    2    1   6.8   3.7   13.0  55.4    -4.7    162  0.8
  7000    6.5  43.7   140    2    1   6.9   3.8   12.8  55.0    -5.0    139  0.7
  6750    7.0  44.6   140    1    1   6.8   3.7   12.5  54.6    -5.2    116  0.6
  6500    7.6  45.7   130    1    0   7.0   3.8   12.3  54.2    -5.4     94  0.5
  6250    8.1  46.6   000    0    0   6.3   3.5   12.1  53.8    -5.6     71  0.4
  6000    8.4  47.1   330    1    0   2.5   1.4   11.7  53.1    -6.0     53  0.3
  5750    8.4  47.1   070    1    0   0.4   0.2   11.1  51.9    -6.8     46  0.2
  5500    8.4  47.1   100    2    1   1.1   0.6   10.4  50.7    -7.5     39  0.2

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

           05/23/2015 at 0900 MDT          |       05/23/2015 at 1200 MDT
                                           |
K index... +18.7  LI... +271.6             | K index... +22.1  LI... +270.4
CAPE... +150.4  CIN... -61.4               | CAPE... +377.9  CIN... -2.9
                                           |
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 -57.1 -70.8  230  31 16   1.9   1.1 | -56.1 -69.0  220  26 14   1.8   1.0
 45000 -54.7 -66.5  220  50 26  -2.3  -1.3 | -53.7 -64.7  215  47 24  -1.2  -0.7
 40000 -58.0 -72.4  200  88 45  -2.2  -1.2 | -55.6 -68.1  195  86 44  -1.2  -0.7
 38000 -55.9 -68.6  195  93 48   6.3   3.5 | -53.9 -65.0  195  93 48   4.8   2.6
 36000 -52.1 -61.8  195  92 48   6.3   3.5 | -51.0 -59.8  195  96 49   4.8   2.6
 34000 -48.2 -54.8  195  90 47   6.8   3.7 | -47.9 -54.2  195  96 50   6.4   3.5
 32000 -44.1 -47.4  200  86 44   6.8   3.7 | -44.0 -47.2  200  93 48   6.4   3.5
 30000 -39.6 -39.3  200  79 41   6.3   3.5 | -39.7 -39.5  200  85 44   6.3   3.4
 29000 -37.7 -35.9  200  76 39   6.4   3.5 | -37.8 -36.0  200  78 40   6.3   3.4
 28000 -35.8 -32.4  200  72 37   6.4   3.5 | -35.9 -32.6  200  71 37   6.3   3.4
 27000 -33.9 -29.0  200  69 35   6.9   3.8 | -34.1 -29.4  200  65 33   6.3   3.5
 26000 -31.8 -25.2  200  64 33   6.9   3.8 | -32.2 -26.0  195  58 30   6.3   3.5
 25000 -29.8 -21.6  200  60 31   6.9   3.8 | -30.3 -22.5  195  52 27   6.4   3.5
 24000 -27.7 -17.9  200  55 28   7.3   4.0 | -28.4 -19.1  190  45 23   7.3   4.0
 23000 -25.5 -13.9  200  53 27   7.4   4.1 | -26.1 -15.0  190  41 21   7.8   4.3
 22000 -23.2  -9.8  200  50 26   7.4   4.1 | -23.8 -10.8  190  37 19   7.8   4.3
 21000 -21.0  -5.8  200  47 24   7.3   4.0 | -21.5  -6.7  190  33 17   7.8   4.3
 20000 -18.8  -1.8  205  43 22   7.3   4.0 | -19.2  -2.6  190  30 15   7.8   4.3
 19500 -17.8  -0.0  205  42 21   7.3   4.0 | -18.0  -0.4  190  28 15   7.8   4.3
 19000 -16.7   1.9  205  40 20   7.3   4.0 | -16.9   1.6  190  27 14   7.8   4.3
 18500 -15.6   3.9  205  38 20   7.4   4.1 | -15.8   3.6  185  25 13   7.5   4.1
 18000 -14.5   5.9  205  36 18   7.4   4.1 | -14.7   5.5  185  24 13   7.4   4.1
 17500 -13.4   7.9  205  34 17   7.4   4.1 | -13.6   7.5  185  24 12   7.4   4.1
 17000 -12.3   9.9  205  32 16   7.3   4.0 | -12.5   9.5  185  23 12   7.3   4.0
 16500 -11.2  11.8  205  30 15   7.2   4.0 | -11.4  11.5  180  22 12   7.3   4.0
 16000  -9.4  15.1  205  28 14   9.0   4.9 |  -9.7  14.5  180  22 11   7.9   4.3
 15500  -8.1  17.4  205  27 14   9.0   4.9 |  -8.6  16.5  180  21 11   7.9   4.3
 15000  -6.8  19.8  205  25 13   9.1   5.0 |  -7.4  18.7  180  21 11   7.7   4.2
 14500  -5.4  22.3  205  24 12   9.1   5.0 |  -6.2  20.8  180  20 11   7.7   4.2
 14000  -4.1  24.6  205  23 12   8.8   4.8 |  -5.1  22.8  180  20 11   7.9   4.3
 13500  -2.8  27.0  205  21 11   8.8   4.8 |  -3.9  25.0  180  21 11   8.0   4.4
 13000  -1.5  29.3  205  19 10   8.1   4.4 |  -2.8  27.0  180  21 11   7.4   4.0
 12500  -0.4  31.3  205  17  9   8.0   4.4 |  -1.7  28.9  185  21 11   7.2   4.0
 12000   0.7  33.3  205  16  8   5.4   3.0 |  -0.7  30.7  185  21 11   7.0   3.8
 11500   1.3  34.3  200  14  7   4.6   2.5 |   0.3  32.5  185  21 11   6.9   3.8
 11000   1.8  35.2  195  12  6   3.5   1.9 |   1.3  34.3  185  20 10   5.7   3.1
 10500   2.1  35.8  195  11  6   3.6   2.0 |   2.0  35.6  185  19 10   4.5   2.5
 10250   2.3  36.1  200  11  6   0.0   0.0 |   2.4  36.3  185  19 10   7.7   4.2
 10000   2.2  36.0  200  11  6   1.8   1.0 |   3.1  37.6  185  17  9   7.9   4.3
  9750   2.6  36.7  200  11  5   6.6   3.6 |   3.4  38.1  185  16  8   4.7   2.6
  9500   3.0  37.4  200  10  5   5.5   3.0 |   3.8  38.8  185  15  8   5.7   3.1
  9250   3.4  38.1  205  10  5   5.5   3.0 |   4.2  39.6  185  14  7   5.1   2.8
  9000   3.7  38.7  200  10  5   6.0   3.3 |   4.5  40.1  185  12  6   5.5   3.0
  8750   4.2  39.6  200   9  5   7.1   3.9 |   4.9  40.8  180  10  5   6.3   3.4
  8500   4.7  40.5  195   8  4   7.5   4.1 |   5.3  41.5  170   8  4   5.7   3.1
  8250   5.1  41.2  195   8  4   6.2   3.4 |   5.6  42.1  160   7  3   8.2   4.5
  8000   5.5  41.9  190   6  3   5.0   2.7 |   6.4  43.5  155   6  3  10.8   6.0
  7750   5.9  42.6  185   5  3   6.3   3.5 |   7.1  44.8  150   6  3   9.9   5.4
  7500   6.3  43.3  180   4  2   6.7   3.7 |   7.8  46.0  145   6  3   9.6   5.3
  7250   6.7  44.1  175   3  2   5.1   2.8 |   8.5  47.3  145   6  3  10.2   5.6
  7000   7.1  44.8  175   3  1   4.5   2.5 |   9.3  48.7  140   5  3  10.6   5.8
  6750   7.4  45.3  175   2  1   3.1   1.7 |  10.1  50.2  140   5  3   9.6   5.3
  6500   7.6  45.7  180   2  1   4.6   2.5 |  10.8  51.4  140   5  3   9.9   5.4
  6250   8.1  46.6  180   2  1   8.3   4.6 |  11.6  52.9  140   5  3  11.3   6.2
  6000   8.7  47.7  180   1  1   7.6   4.2 |  12.4  54.3  140   5  3  11.1   6.1
  5750   9.3  48.7  180   1  0  10.3   5.6 |  13.2  55.8  135   5  2  11.6   6.3
  5500  10.3  50.5  175   1  0  18.9  10.4 |  14.3  57.7  135   5  2  19.3  10.6

           05/23/2015 at 1500 MDT          |       05/23/2015 at 1800 MDT
                                           |
K index... +26.8  LI... +270.8             | K index... +25.3  LI... +271.3
CAPE... +366.0  CIN... M                   | CAPE... +219.9  CIN... -1.2
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -56.3 -69.3  215  22 11   1.5   0.8 | -56.5 -69.7  210  18  9   1.8   1.0
 45000 -54.2 -65.6  210  40 20  -0.9  -0.5 | -54.2 -65.6  200  31 16  -1.1  -0.6
 40000 -55.7 -68.3  195  82 42  -0.9  -0.5 | -55.9 -68.6  190  80 41  -1.1  -0.6
 38000 -53.8 -64.8  195  92 48   5.0   2.8 | -53.9 -65.0  190  89 46   5.4   3.0
 36000 -50.8 -59.4  190  99 51   5.0   2.7 | -50.7 -59.3  190  94 48   5.4   3.0
 34000 -47.5 -53.5  190 102 52   6.9   3.8 | -47.2 -53.0  190  95 49   6.7   3.7
 32000 -42.8 -45.0  195  93 48   7.0   3.8 | -42.7 -44.9  195  85 44   6.7   3.7
 30000 -38.8 -37.8  200  79 41   6.0   3.3 | -38.8 -37.8  195  73 37   5.8   3.2
 29000 -37.0 -34.6  200  67 34   6.1   3.3 | -37.1 -34.8  195  62 32   5.8   3.2
 28000 -35.2 -31.4  200  54 28   6.1   3.3 | -35.4 -31.7  195  52 27   5.8   3.2
 27000 -33.4 -28.1  200  43 22   7.1   3.9 | -33.5 -28.3  195  43 22   7.8   4.3
 26000 -31.2 -24.2  195  40 20   7.1   3.9 | -31.2 -24.2  190  39 20   7.9   4.4
 25000 -29.1 -20.4  195  36 19   7.1   3.9 | -28.8 -19.8  190  35 18   8.0   4.4
 24000 -27.0 -16.6  190  33 17   7.4   4.1 | -26.5 -15.7  185  32 16   7.6   4.2
 23000 -24.7 -12.5  190  30 15   7.6   4.2 | -24.3 -11.7  185  28 14   7.4   4.0
 22000 -22.5  -8.5  195  27 14   7.7   4.2 | -22.1  -7.8  185  23 12   7.4   4.0
 21000 -20.2  -4.4  195  25 13   7.2   4.0 | -20.0  -4.0  185  20 10   7.0   3.8
 20000 -18.1  -0.6  190  25 13   7.2   3.9 | -17.9  -0.2  190  19 10   6.9   3.8
 19500 -17.1   1.2  185  25 13   7.2   4.0 | -16.9   1.6  195  19 10   6.9   3.8
 19000 -16.0   3.2  185  25 13   7.2   4.0 | -15.9   3.4  200  19 10   6.9   3.8
 18500 -14.9   5.2  185  26 13   7.1   3.9 | -14.8   5.4  205  20 10   7.0   3.8
 18000 -13.9   7.0  180  26 14   7.0   3.8 | -13.8   7.2  205  20 10   7.0   3.8
 17500 -12.9   8.8  180  27 14   7.0   3.8 | -12.8   9.0  210  20 10   7.0   3.8
 17000 -11.4  11.5  180  26 14   6.7   3.7 | -11.7  10.9  210  20 10   7.2   4.0
 16500 -10.4  13.3  185  26 13   6.7   3.7 | -10.2  13.6  210  20 10   7.2   3.9
 16000  -9.4  15.1  185  25 13   6.8   3.7 |  -9.1  15.6  210  20 10   6.8   3.7
 15500  -8.4  16.9  185  25 13   6.8   3.7 |  -8.1  17.4  210  20 10   6.8   3.8
 15000  -7.4  18.7  185  24 12   6.8   3.7 |  -7.2  19.0  210  19 10   6.4   3.5
 14500  -6.4  20.5  185  23 12   6.8   3.7 |  -6.2  20.8  210  19 10   6.4   3.5
 14000  -5.4  22.3  185  22 11   6.3   3.5 |  -5.3  22.5  205  19 10   6.5   3.5
 13500  -4.5  23.9  185  21 11   6.2   3.4 |  -4.3  24.3  200  18  9   6.5   3.5
 13000  -3.6  25.5  185  19 10   6.3   3.4 |  -3.4  25.9  195  17  9   6.4   3.5
 12500  -2.7  27.1  185  19 10   6.4   3.5 |  -2.5  27.5  185  16  8   6.4   3.5
 12000  -1.8  28.8  185  18  9   6.4   3.5 |  -1.6  29.1  175  16  8   6.7   3.7
 11500  -0.9  30.4  175  16  8   6.5   3.6 |  -0.6  30.9  170  15  8   7.1   3.9
 11000   0.0  32.0  165  15  8   6.8   3.7 |   0.4  32.7  165  14  7   7.7   4.2
 10500   1.0  33.8  160  14  7   6.6   3.6 |   1.6  34.9  165  13  7   8.0   4.4
 10250   1.5  34.7  155  14  7   9.6   5.3 |   2.2  36.0  165  13  7  10.0   5.5
 10000   2.3  36.1  155  13  7  11.6   6.3 |   3.0  37.4  165  12  6  11.4   6.2
  9750   3.0  37.4  155  13  7  10.0   5.5 |   3.8  38.8  165  12  6  10.4   5.7
  9500   3.8  38.8  155  13  7  10.5   5.8 |   4.6  40.3  165  12  6  10.6   5.8
  9250   4.6  40.3  155  13  6  10.1   5.5 |   5.3  41.5  165  12  6  10.6   5.8
  9000   5.3  41.5  155  12  6  10.1   5.5 |   6.1  43.0  165  12  6  10.1   5.6
  8750   6.0  42.8  155  12  6  10.4   5.7 |   6.8  44.2  165  12  6   9.7   5.3
  8500   6.8  44.2  155  12  6  10.2   5.6 |   7.5  45.5  165  11  6   9.7   5.3
  8250   7.6  45.7  155  12  6  10.6   5.8 |   8.3  46.9  165  11  6  10.2   5.6
  8000   8.4  47.1  155  12  6  10.5   5.8 |   9.1  48.4  165  11  6  10.5   5.8
  7750   9.1  48.4  155  12  6   9.7   5.3 |   9.8  49.6  170  11  6   9.7   5.3
  7500   9.8  49.6  155  12  6   9.1   5.0 |  10.5  50.9  170  11  6   9.0   4.9
  7250  10.5  50.9  155  12  6  10.2   5.6 |  11.2  52.2  170  11  5  10.1   5.6
  7000  11.3  52.3  155  11  6  11.2   6.1 |  12.0  53.6  170  10  5  11.2   6.2
  6750  12.1  53.8  155  11  6   9.9   5.4 |  12.8  55.0  170  10  5   9.7   5.3
  6500  12.8  55.0  155  11  6   9.7   5.3 |  13.5  56.3  170  10  5   8.9   4.9
  6250  13.6  56.5  155  11  6  10.6   5.8 |  14.2  57.6  170  10  5  10.1   5.5
  6000  14.4  57.9  155  11  5  11.4   6.2 |  15.0  59.0  170   9  5  10.9   6.0
  5750  15.2  59.4  155  10  5   9.4   5.2 |  15.7  60.3  170   9  5   9.7   5.3
  5500  16.0  60.8  155  10  5  13.5   7.4 |  16.5  61.7  175   8  4  10.8   5.9
________________________________________________________________________________

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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