Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210046
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1846 MDT Wednesday, May 20, 2015

This forecast is for Thursday, May 21, 2015:

If the trigger temperature of 62.1 F/16.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9106 ft MSL (3799 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... None
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................. 8004 ft MSL (2698 ft AGL)
Thermal soaring outlook for Friday 05/22....... Poor

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....................... 15902 ft MSL (10595 ft AGL)
Wave soaring outlook for Friday 05/22.......... Poor

Remarks...

Sunrise/Sunset.................... 05:40:10 / 20:11:47 MDT
Total possible sunshine........... 14 hr 31 min 37 sec (871 min 37 sec)
Altitude of sun at 12:56:11 MDT... 70.45 degrees

Upper air data from numerical model forecast valid on 05/21/2015 at 0600 MDT

Freezing level.................. 12614 ft MSL (7307 ft AGL)
Convective condensation level... 13138 ft MSL (7831 ft AGL)
Lifted condensation level....... 10762 ft MSL (5455 ft AGL)
Lifted index.................... +0.6
K index......................... +16.8

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  -59.3 -74.7   265   35   18  -0.9  -0.5      M     M       M      M    M
 45000  -60.6 -77.1   255   59   30  -0.4  -0.2      M     M       M      M    M
 40000  -61.3 -78.3   260   76   39  -0.4  -0.2      M     M       M      M    M
 38000  -58.8 -73.8   260   75   39   6.6   3.6      M     M       M      M    M
 36000  -54.8 -66.6   260   71   36   6.6   3.6      M     M       M      M    M
 34000  -50.2 -58.4   260   65   34   7.2   3.9      M     M       M      M    M
 32000  -45.9 -50.6   255   60   31   7.2   3.9      M     M       M      M    M
 30000  -41.3 -42.3   255   53   27   8.4   4.6   34.4  93.9    13.8      M    M
 29000  -38.7 -37.7   255   48   25   8.4   4.6   33.8  92.9    13.5      M    M
 28000  -36.2 -33.2   255   44   23   8.4   4.6   33.4  92.1    13.3      M    M
 27000  -33.7 -28.7   255   39   20   8.0   4.4   32.9  91.1    13.1      M    M
 26000  -31.3 -24.3   250   34   18   8.0   4.4   32.1  89.8    12.6      M    M
 25000  -28.9 -20.0   245   29   15   8.1   4.4   31.5  88.7    12.3      M    M
 24000  -26.7 -16.1   240   25   13   4.7   2.6   30.7  87.2    11.7      M    M
 23000  -25.3 -13.5   250   22   11   4.9   2.7   28.8  83.8    10.3      M    M
 22000  -23.8 -10.8   260   20   10   5.0   2.8   27.1  80.8     9.0      M    M
 21000  -22.0  -7.6   270   20   10   8.6   4.7   25.9  78.6     8.0      M    M
 20000  -19.5  -3.1   275   21   11   8.4   4.6   25.3  77.6     7.7      M    M
 19500  -18.2  -0.8   280   22   11   8.4   4.6   25.1  77.2     7.5      M    M
 19000  -16.9   1.6   280   23   12   8.4   4.6   24.9  76.9     7.4      M    M
 18500  -15.7   3.7   280   23   12   8.1   4.5   24.7  76.5     7.2      M    M
 18000  -14.5   5.9   280   22   12   8.2   4.5   24.4  75.9     7.0      M    M
 17500  -12.6   9.3   275   22   11   9.3   5.1   24.1  75.4     6.8      M    M
 17000  -11.2  11.8   275   23   12   9.3   5.1   24.0  75.2     6.8      M    M
 16500   -9.8  14.4   275   24   12   8.8   4.8   23.9  75.1     6.7      M    M
 16000   -8.6  16.5   275   25   13   8.7   4.8   23.7  74.7     6.5      M    M
 15500   -7.3  18.9   275   26   14   8.6   4.7   23.5  74.4     6.4      M    M
 15000   -6.0  21.2   280   25   13   8.6   4.7   23.3  74.0     6.2      M    M
 14500   -4.8  23.4   280   23   12   8.7   4.8   23.2  73.7     6.1      M    M
 14000   -3.5  25.7   280   22   11   9.1   5.0   23.0  73.4     5.9      M    M
 13500   -2.1  28.2   285   21   11   9.1   5.0   22.9  73.2     5.8      M    M
 13000   -0.8  30.6   285   20   10   8.6   4.7   22.7  72.9     5.7      M    M
 12500    0.4  32.7   285   18    9   8.8   4.8   22.6  72.6     5.5      M    M
 12000    1.6  34.9   285   16    8   7.9   4.3   22.3  72.2     5.3      M    M
 11500    2.8  37.0   285   15    8   8.3   4.6   22.0  71.7     5.0      M    M
 11000    3.7  38.7   280   14    7   4.2   2.3   21.5  70.7     4.5      M    M
 10500    4.3  39.7   275   14    7   5.0   2.8   20.6  69.1     3.6      M    M
 10250    4.6  40.3   270   14    7   1.3   0.7   20.2  68.4     3.2      M    M
 10000    4.5  40.1   270   14    7  -0.4  -0.2   19.4  66.9     2.4      M    M
  9750    4.6  40.3   265   14    7   2.0   1.1   18.7  65.7     1.8      M    M
  9500    4.7  40.5   255   15    8   1.6   0.9   18.1  64.5     1.1      M    M
  9250    4.7  40.5   250   15    8   0.5   0.2   17.4  63.3     0.5      M    M
  9000    4.7  40.5   245   15    8  -0.1  -0.1   16.6  61.9    -0.3    271  1.4
  8750    4.7  40.5   240   15    8   1.0   0.6   15.9  60.6    -1.1    263  1.3
  8500    4.7  40.5   230   15    8   1.4   0.8   15.2  59.4    -1.7    255  1.3
  8250    4.8  40.6   225   14    7   2.1   1.2   14.6  58.3    -2.4    244  1.2
  8000    5.0  41.0   220   13    7   2.6   1.4   14.1  57.3    -3.0    232  1.2
  7750    5.1  41.2   215   13    6  -0.2  -0.1   13.4  56.2    -3.6    222  1.1
  7500    5.0  41.0   205   12    6   1.3   0.7   12.6  54.7    -4.4    217  1.1
  7250    5.3  41.5   200   12    6   5.0   2.7   12.2  53.9    -4.9    201  1.0
  7000    5.6  42.1   190   12    6   4.9   2.7   11.8  53.3    -5.3    184  0.9
  6750    6.0  42.8   180   13    7   3.6   2.0   11.4  52.6    -5.7    166  0.8
  6500    6.1  43.0   175   13    7   2.0   1.1   10.9  51.6    -6.3    154  0.8
  6250    6.3  43.3   170   11    6   2.5   1.4   10.3  50.5    -6.9    142  0.7
  6000    6.4  43.5   165    9    5   1.4   0.8    9.7  49.5    -7.5    130  0.7
  5750    6.4  43.5   150    7    3  -1.7  -0.9    9.0  48.2    -8.2    123  0.6
  5500    6.2  43.2   135    4    2  -3.8  -2.1    8.0  46.5    -9.2    123  0.6

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

           05/21/2015 at 0900 MDT          |       05/21/2015 at 1200 MDT
                                           |
K index... +16.5  LI... +273.6             | K index... +16.0  LI... +271.2
CAPE... +1.1  CIN... -152.5                | CAPE... +165.5  CIN... -153.9
                                           |
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 -59.8 -75.6  265  32 16   0.1   0.0 | -60.1 -76.2  255  33 17  -0.1  -0.0
 45000 -59.8 -75.6  260  57 29  -0.8  -0.4 | -60.3 -76.5  255  56 29  -0.4  -0.2
 40000 -60.9 -77.6  260  80 41  -0.6  -0.4 | -60.9 -77.6  255  88 46  -0.3  -0.1
 38000 -58.2 -72.8  260  81 41   6.7   3.7 | -58.0 -72.4  255  87 45   7.0   3.8
 36000 -54.2 -65.6  260  77 40   6.7   3.7 | -53.3 -63.9  255  80 41   7.0   3.8
 34000 -49.5 -57.1  260  73 37   7.3   4.0 | -48.9 -56.0  255  73 38   7.7   4.2
 32000 -45.1 -49.2  260  69 35   7.3   4.0 | -44.3 -47.7  255  67 35   7.7   4.2
 30000 -40.6 -41.1  260  61 31   7.8   4.3 | -39.6 -39.3  255  58 30   8.1   4.5
 29000 -38.2 -36.8  260  55 28   7.9   4.3 | -37.1 -34.8  255  51 26   8.1   4.5
 28000 -35.9 -32.6  260  48 25   7.8   4.3 | -34.7 -30.5  250  45 23   8.1   4.4
 27000 -33.7 -28.7  255  42 22   6.5   3.6 | -32.5 -26.5  250  39 20   5.5   3.0
 26000 -31.7 -25.1  250  35 18   6.6   3.6 | -30.9 -23.6  250  34 18   5.6   3.1
 25000 -29.7 -21.5  240  30 15   6.6   3.6 | -29.2 -20.6  250  30 15   5.6   3.1
 24000 -27.8 -18.0  230  25 13   6.0   3.3 | -27.4 -17.3  245  26 13   7.6   4.2
 23000 -26.0 -14.8  235  22 12   6.0   3.3 | -25.2 -13.4  245  26 13   7.5   4.1
 22000 -24.2 -11.6  245  20 10   6.1   3.3 | -23.0  -9.4  245  25 13   7.5   4.1
 21000 -22.1  -7.8  255  18 10   8.8   4.8 | -20.8  -5.4  245  25 13   7.1   3.9
 20000 -19.5  -3.1  255  18 10   8.7   4.8 | -18.7  -1.7  250  23 12   7.1   3.9
 19500 -18.2  -0.8  260  18 10   8.7   4.8 | -17.6   0.3  250  22 11   7.1   3.9
 19000 -16.9   1.6  260  19 10   8.7   4.8 | -16.5   2.3  250  21 11   7.1   3.9
 18500 -15.5   4.1  265  19 10  10.0   5.5 | -14.9   5.2  250  19 10   7.4   4.0
 18000 -14.0   6.8  265  19 10   9.9   5.4 | -13.8   7.2  250  18  9   7.4   4.1
 17500 -11.9  10.6  265  19 10   8.9   4.9 | -12.6   9.3  250  16  8   8.4   4.6
 17000 -10.6  12.9  270  21 11   9.0   5.0 | -11.4  11.5  255  15  8   8.2   4.5
 16500  -9.3  15.3  275  22 11   8.5   4.6 | -10.1  13.8  255  14  7   9.8   5.4
 16000  -8.0  17.6  275  21 11   8.4   4.6 |  -8.5  16.7  255  13  7  10.2   5.6
 15500  -6.8  19.8  275  20 10   8.2   4.5 |  -7.0  19.4  255  12  6   9.8   5.4
 15000  -5.6  21.9  280  19 10   8.1   4.4 |  -5.6  21.9  255  10  5   9.2   5.1
 14500  -4.4  24.1  280  17  9   8.1   4.4 |  -4.2  24.4  255   9  5   9.0   4.9
 14000  -3.2  26.2  285  16  8   8.1   4.5 |  -3.0  26.6  255   8  4   7.9   4.3
 13500  -2.0  28.4  290  15  8   8.1   4.4 |  -1.8  28.8  250   7  3   7.9   4.3
 13000  -0.7  30.7  290  14  7   9.1   5.0 |  -0.5  31.1  245   5  3   9.0   4.9
 12500   0.6  33.1  295  12  6   9.2   5.0 |   0.8  33.4  235   4  2   9.0   4.9
 12000   1.9  35.4  300  11  6   7.7   4.2 |   2.0  35.6  215   3  2   7.7   4.2
 11500   3.0  37.4  300   9  5   8.1   4.4 |   3.2  37.8  195   3  2   8.0   4.4
 11000   3.9  39.0  305   8  4   5.5   3.0 |   4.2  39.6  175   3  2   6.5   3.6
 10500   4.7  40.5  310   6  3   6.4   3.5 |   5.1  41.2  160   4  2   7.5   4.1
 10250   5.1  41.2  310   5  2   2.9   1.6 |   5.6  42.1  155   4  2   3.5   1.9
 10000   5.2  41.4  310   4  2   1.0   0.6 |   5.6  42.1  155   4  2   0.6   0.3
  9750   5.3  41.5  300   4  2   3.1   1.7 |   5.7  42.3  155   5  2   2.4   1.3
  9500   5.5  41.9  290   3  1   2.8   1.5 |   5.9  42.6  150   5  3   2.1   1.2
  9250   5.6  42.1  275   2  1   0.5   0.3 |   5.9  42.6  150   5  3   0.2   0.1
  9000   5.5  41.9  250   2  1  -1.6  -0.9 |   5.8  42.4  150   5  3  -1.6  -0.9
  8750   5.4  41.7  225   2  1  -1.0  -0.6 |   5.6  42.1  150   5  3  -1.6  -0.9
  8500   5.2  41.4  205   3  2  -1.2  -0.7 |   5.4  41.7  145   5  2  -0.1  -0.0
  8250   5.1  41.2  200   4  2  -1.6  -0.9 |   5.4  41.7  140   4  2   4.6   2.5
  8000   4.9  40.8  200   4  2  -1.4  -0.8 |   5.9  42.6  135   4  2   6.9   3.8
  7750   4.8  40.6  205   4  2  -2.3  -1.3 |   6.3  43.3  130   4  2   7.8   4.3
  7500   4.6  40.3  210   4  2   1.7   0.9 |   7.0  44.6  125   4  2   9.5   5.2
  7250   5.0  41.0  195   4  2   6.2   3.4 |   7.7  45.9  125   4  2  10.0   5.5
  7000   5.4  41.7  180   4  2   5.6   3.1 |   8.4  47.1  125   4  2   9.9   5.5
  6750   5.8  42.4  170   5  3   5.4   3.0 |   9.2  48.6  125   4  2   9.8   5.4
  6500   6.2  43.2  160   4  2   7.1   3.9 |   9.9  49.8  125   3  2  10.2   5.6
  6250   6.8  44.2  160   4  2   8.7   4.7 |  10.7  51.3  125   3  2  11.1   6.1
  6000   7.4  45.3  160   3  1   8.4   4.6 |  11.5  52.7  125   3  2   9.5   5.2
  5750   8.1  46.6  160   2  1  13.0   7.1 |  12.3  54.1  125   3  1  14.8   8.1
  5500   9.4  48.9  160   2  1  19.7  10.8 |  13.9  57.0  125   3  1  27.8  15.2

           05/21/2015 at 1500 MDT          |       05/21/2015 at 1800 MDT
                                           |
K index... +19.7  LI... +267.9             | K index... +23.4  LI... +272.0
CAPE... +685.1  CIN... -0.0                | CAPE... +181.1  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 -60.5 -76.9  255  37 19  -0.5  -0.3 | -59.7 -75.5  250  38 20   0.8   0.4
 45000 -61.2 -78.2  255  60 31   0.6   0.3 | -58.8 -73.8  250  62 32  -2.6  -1.4
 40000 -60.4 -76.7  240  94 48   0.7   0.4 | -62.3 -80.1  235  85 44  -2.3  -1.3
 38000 -57.6 -71.7  240  91 47   6.4   3.5 | -58.7 -73.7  235  78 40   8.1   4.4
 36000 -53.2 -63.8  240  79 41   6.4   3.5 | -53.9 -65.0  235  66 34   8.1   4.4
 34000 -48.9 -56.0  240  69 36   8.0   4.4 | -48.9 -56.0  235  55 28   8.5   4.7
 32000 -44.1 -47.4  245  58 30   8.0   4.4 | -43.8 -46.8  245  44 23   8.5   4.7
 30000 -39.4 -38.9  250  47 24   8.0   4.4 | -38.8 -37.8  250  35 18   8.1   4.4
 29000 -37.0 -34.6  250  41 21   8.0   4.4 | -35.8 -32.4  250  31 16   8.1   4.4
 28000 -34.6 -30.3  255  35 18   8.0   4.4 | -33.4 -28.1  250  28 14   8.1   4.4
 27000 -32.2 -26.0  255  30 15   7.5   4.1 | -31.1 -24.0  255  26 13   7.7   4.2
 26000 -30.0 -22.0  255  26 13   7.5   4.1 | -28.8 -19.8  255  25 13   7.7   4.2
 25000 -27.8 -18.0  255  22 12   7.5   4.1 | -26.5 -15.7  255  25 13   7.7   4.2
 24000 -25.6 -14.1  250  19 10   6.5   3.6 | -24.3 -11.7  255  24 12   6.9   3.8
 23000 -23.6 -10.5  245  19 10   6.6   3.6 | -22.2  -8.0  250  25 13   7.0   3.8
 22000 -21.7  -7.1  245  19 10   6.6   3.6 | -20.2  -4.4  240  25 13   7.0   3.8
 21000 -19.9  -3.8  235  18  9   5.4   2.9 | -18.1  -0.6  235  26 13   7.0   3.9
 20000 -18.3  -0.9  225  18  9   5.4   3.0 | -16.1   3.0  225  26 14   7.1   3.9
 19500 -17.5   0.5  220  17  9   5.4   3.0 | -15.0   5.0  220  27 14   7.1   3.9
 19000 -16.6   2.1  215  18  9   5.1   2.8 | -14.0   6.8  215  27 14   7.3   4.0
 18500 -15.0   5.0  205  17  9   8.1   4.5 | -13.1   8.4  210  26 14   4.6   2.5
 18000 -13.8   7.2  200  17  9   8.2   4.5 | -12.4   9.7  200  25 13   4.9   2.7
 17500 -12.6   9.3  195  16  8   8.2   4.5 | -11.7  10.9  195  24 12   5.6   3.1
 17000 -11.4  11.5  190  15  8   8.2   4.5 | -10.8  12.6  190  24 12   6.1   3.4
 16500 -10.2  13.6  185  14  7   8.6   4.7 |  -9.9  14.2  185  23 12   6.2   3.4
 16000  -8.8  16.2  180  14  7   8.8   4.8 |  -9.0  15.8  180  23 12   6.4   3.5
 15500  -7.5  18.5  175  14  7   9.2   5.0 |  -8.0  17.6  180  22 12   6.4   3.5
 15000  -6.0  21.2  170  14  7  10.0   5.5 |  -6.6  20.1  180  21 11   6.7   3.7
 14500  -4.5  23.9  170  14  7   9.9   5.4 |  -5.6  21.9  175  20 11   6.7   3.7
 14000  -3.1  26.4  165  14  7   8.9   4.9 |  -4.6  23.7  175  19 10   6.7   3.7
 13500  -1.8  28.8  165  13  7   9.1   5.0 |  -3.6  25.5  170  18  9   6.8   3.7
 13000  -0.6  30.9  160  13  7   7.9   4.3 |  -2.7  27.1  165  16  8   6.0   3.3
 12500   0.6  33.1  160  12  6   8.4   4.6 |  -1.8  28.8  165  13  7   6.1   3.3
 12000   1.6  34.9  155  12  6   4.9   2.7 |  -1.0  30.2  160  11  6   5.7   3.1
 11500   2.3  36.1  155  11  6   5.3   2.9 |  -0.1  31.8  150   9  4   5.7   3.1
 11000   2.8  37.0  155  10  5   2.0   1.1 |   0.7  33.3  145   7  4   6.2   3.4
 10500   2.9  37.2  150   8  4   2.2   1.2 |   1.6  34.9  150   7  4   6.7   3.7
 10250   3.0  37.4  150   7  4   1.5   0.8 |   2.0  35.6  150   7  4   4.2   2.3
 10000   3.2  37.8  150   7  4   5.9   3.2 |   2.2  36.0  150   8  4   6.3   3.4
  9750   3.8  38.8  145   6  3   9.8   5.4 |   2.9  37.2  150   8  4  10.1   5.6
  9500   4.3  39.7  140   5  3   9.3   5.1 |   3.5  38.3  150   9  5   9.6   5.3
  9250   4.9  40.8  130   5  2   8.1   4.5 |   4.1  39.4  150  10  5   8.2   4.5
  9000   5.4  41.7  130   5  3   8.4   4.6 |   4.7  40.5  150  10  5   8.4   4.6
  8750   6.1  43.0  135   6  3  10.3   5.7 |   5.4  41.7  150  10  5  10.4   5.7
  8500   6.8  44.2  135   6  3  10.0   5.5 |   6.1  43.0  150   9  5  10.0   5.5
  8250   7.6  45.7  135   7  4   9.9   5.4 |   6.9  44.4  145   9  5  10.6   5.8
  8000   8.3  46.9  135   7  4   9.9   5.4 |   7.7  45.9  145   9  5  10.7   5.9
  7750   9.0  48.2  135   7  4  10.3   5.7 |   8.4  47.1  145   9  5  10.1   5.5
  7500   9.8  49.6  135   7  4  10.3   5.7 |   9.2  48.6  145   9  5  10.0   5.5
  7250  10.6  51.1  135   7  4  10.1   5.5 |   9.9  49.8  145   9  4  10.1   5.6
  7000  11.3  52.3  130   7  4  10.1   5.5 |  10.7  51.3  145   9  4  10.1   5.5
  6750  12.1  53.8  130   7  4   9.3   5.1 |  11.4  52.5  145   9  4   9.5   5.2
  6500  12.8  55.0  130   7  4  10.0   5.5 |  12.1  53.8  145   8  4   9.6   5.3
  6250  13.6  56.5  130   7  4  11.6   6.3 |  12.8  55.0  145   8  4  10.2   5.6
  6000  14.4  57.9  130   7  3   9.9   5.4 |  13.6  56.5  145   8  4  10.0   5.5
  5750  15.2  59.4  130   7  3  13.6   7.4 |  14.3  57.7  145   7  4  10.1   5.5
  5500  16.6  61.9  130   7  3  24.7  13.5 |  15.0  59.0  140   7  3  10.5   5.7
________________________________________________________________________________

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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