Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 280205
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
2005 MDT Monday, July 27, 2015

This forecast is for Tuesday, July 28, 2015:

If the trigger temperature of 79.4 F/26.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 647 ft/min (3.3 m/s)
   Maximum height of thermals.................. 13397 ft MSL (8090 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1200 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10278 ft MSL (4971 ft AGL)
Thermal soaring outlook for Wednesday 07/29.... Excellent

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 16000 ft MSL (10693 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 40783 ft MSL (35476 ft AGL)
Wave soaring outlook for Wednesday 07/29....... Good

Remarks...

Sunrise/Sunset.................... 05:54:41 / 20:17:32 MDT
Total possible sunshine........... 14 hr 22 min 52 sec (862 min 52 sec)
Altitude of sun at 13:05:55 MDT... 69.13 degrees

Upper air data from numerical model forecast valid on 07/28/2015 at 0600 MDT

Freezing level.................. 16411 ft MSL (11104 ft AGL)
Convective condensation level... 19354 ft MSL (14047 ft AGL)
Lifted condensation level....... 17046 ft MSL (11739 ft AGL)
Lifted index.................... +2.1
K index......................... -1.6

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  -65.2 -85.4   235   39   20   1.7   0.9      M     M       M      M    M
 45000  -60.5 -76.9   235   51   26   6.0   3.3      M     M       M      M    M
 40000  -51.5 -60.7   235   58   30   6.5   3.6      M     M       M      M    M
 38000  -47.6 -53.7   235   58   30   6.5   3.6      M     M       M      M    M
 36000  -43.7 -46.7   235   59   30   6.3   3.5      M     M       M      M    M
 34000  -38.5 -37.3   235   55   29   7.8   4.3      M     M       M      M    M
 32000  -33.8 -28.8   240   52   27   8.1   4.4      M     M       M      M    M
 30000  -29.3 -20.7   240   45   23   7.4   4.1   46.6 115.9    12.2      M    M
 29000  -27.1 -16.8   240   42   22   7.4   4.1   45.8 114.4    11.7      M    M
 28000  -24.8 -12.6   240   39   20   7.7   4.2   45.0 113.0    11.3      M    M
 27000  -22.5  -8.5   235   38   20   7.7   4.2   44.1 111.4    10.7      M    M
 26000  -20.2  -4.4   235   37   19   7.7   4.2   43.3 110.0    10.2      M    M
 25000  -17.9  -0.2   235   36   19   7.5   4.1   42.7 108.8     9.8      M    M
 24000  -15.8   3.6   235   34   18   6.7   3.7   41.5 106.7     8.9      M    M
 23000  -13.8   7.2   235   33   17   6.8   3.7   40.4 104.7     8.1      M    M
 22000  -11.8  10.8   235   31   16   7.0   3.8   39.4 102.9     7.4      M    M
 21000   -9.5  14.9   235   29   15   7.6   4.2   38.5 101.4     6.7      M    M
 20000   -7.2  19.0   230   27   14   7.6   4.2   37.8 100.0     6.2      M    M
 19500   -6.1  21.0   230   26   13   7.6   4.2   37.5  99.4     5.9      M    M
 19000   -5.0  23.0   230   25   13   7.5   4.1   37.1  98.8     5.6      M    M
 18500   -3.8  25.2   230   25   13   7.4   4.1   36.7  98.1     5.3      M    M
 18000   -2.7  27.1   230   25   13   6.9   3.8   36.3  97.4     5.0      M    M
 17500   -1.4  29.5   230   23   12   5.4   3.0   35.3  95.5     4.1      M    M
 17000   -0.6  30.9   230   22   11   5.1   2.8   34.6  94.2     3.5      M    M
 16500    0.0  32.0   235   21   11   4.4   2.4   33.7  92.6     2.7      M    M
 16000    0.7  33.3   235   19   10   4.3   2.3   32.8  91.0     1.9      M    M
 15500    1.4  34.5   240   17    9   6.6   3.6   32.1  89.7     1.2      M    M
 15000    2.4  36.3   245   16    8   6.4   3.5   31.5  88.7     0.7      M    M
 14500    3.4  38.1   250   15    8   8.6   4.7   31.1  87.9     0.2      M    M
 14000    4.7  40.5   255   15    8   9.1   5.0   31.0  87.7     0.1      M    M
 13500    6.1  43.0   260   16    8   8.5   4.6   30.9  87.6     0.0      M    M
 13000    7.2  45.0   265   17    9   7.7   4.2   30.5  87.0    -0.3    603  3.1
 12500    8.4  47.1   265   19   10   7.7   4.2   30.2  86.4    -0.7    554  2.8
 12000    9.5  49.1   265   19   10   7.6   4.2   29.9  85.7    -1.0    506  2.6
 11500   10.6  51.1   265   19   10   7.4   4.1   29.5  85.2    -1.4    458  2.3
 11000   11.5  52.7   265   18    9   6.2   3.4   29.0  84.3    -1.9    415  2.1
 10500   12.4  54.3   265   17    9   3.6   2.0   28.5  83.3    -2.5    374  1.9
 10250   12.5  54.5   265   17    9   3.3   1.8   27.9  82.2    -3.1    363  1.8
 10000   13.0  55.4   265   15    8   7.7   4.2   27.6  81.7    -3.4    342  1.7
  9750   13.5  56.3   265   14    7   7.9   4.3   27.5  81.4    -3.6    318  1.6
  9500   14.1  57.4   270   12    6   6.9   3.8   27.3  81.1    -3.8    294  1.5
  9250   14.5  58.1   275   11    6   4.5   2.5   27.0  80.6    -4.1    275  1.4
  9000   14.8  58.6   280   10    5   5.2   2.8   26.6  79.8    -4.6    258  1.3
  8750   15.2  59.4   285   10    5   6.6   3.6   26.3  79.3    -4.9    238  1.2
  8500   15.6  60.1   290    9    5   5.6   3.1   26.0  78.8    -5.2    218  1.1
  8250   16.0  60.8   295    9    5   4.9   2.7   25.6  78.2    -5.6    200  1.0
  8000   16.3  61.3   305   10    5   4.5   2.4   25.3  77.5    -6.0    184  0.9
  7750   16.6  61.9   310   10    5   3.7   2.0   24.8  76.7    -6.5    168  0.9
  7500   16.8  62.2   315   11    6   4.3   2.3   24.4  75.8    -7.0    153  0.8
  7250   17.2  63.0   320   11    6   4.9   2.7   24.0  75.1    -7.4    134  0.7
  7000   17.5  63.5   320   11    6   4.8   2.7   23.6  74.5    -7.8    116  0.6
  6750   17.9  64.2   325   11    5   3.6   2.0   23.2  73.8    -8.2     99  0.5
  6500   18.0  64.4   335    9    5   1.0   0.5   22.6  72.7    -8.8     87  0.4
  6250   18.0  64.4   345    8    4  -1.0  -0.5   21.9  71.4    -9.6     82  0.4
  6000   17.9  64.2   355    7    4   2.6   1.4   21.1  70.0   -10.4     76  0.4
  5750   18.1  64.6   015    7    3  -2.0  -1.1   20.6  69.1   -11.0     64  0.3
  5500   16.9  62.4   040    3    2 -19.4 -10.7   19.1  66.3   -12.9     90  0.5

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

           07/28/2015 at 0900 MDT          |       07/28/2015 at 1200 MDT
                                           |
K index... -4.6  LI... +5.0                | K index... -6.8  LI... +4.0
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.1
                                           |
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 -64.8 -84.6  235  41 21   1.8   1.0 | -64.5 -84.1  230  41 21   1.5   0.8
 45000 -60.3 -76.5  235  53 28   5.7   3.1 | -60.2 -76.4  230  58 30   5.7   3.1
 40000 -51.6 -60.9  235  62 32   6.6   3.6 | -51.5 -60.7  240  65 34   6.6   3.6
 38000 -47.6 -53.7  235  61 31   6.6   3.6 | -47.5 -53.5  235  64 33   6.6   3.6
 36000 -43.6 -46.5  235  61 31   6.5   3.6 | -43.0 -45.4  235  62 32   6.8   3.7
 34000 -38.7 -37.7  235  55 29   7.4   4.1 | -38.8 -37.8  235  58 30   7.1   3.9
 32000 -34.3 -29.7  235  50 26   7.7   4.2 | -34.5 -30.1  235  54 28   7.4   4.0
 30000 -29.5 -21.1  235  47 24   7.9   4.4 | -29.6 -21.3  235  51 26   8.3   4.6
 29000 -27.1 -16.8  235  45 23   7.9   4.4 | -27.1 -16.8  235  49 25   8.3   4.6
 28000 -24.8 -12.6  235  44 22   7.1   3.9 | -24.6 -12.3  235  47 24   7.0   3.9
 27000 -22.7  -8.9  235  41 21   6.9   3.8 | -22.6  -8.7  240  44 23   6.8   3.7
 26000 -20.6  -5.1  240  39 20   6.9   3.8 | -20.6  -5.1  240  41 21   6.8   3.7
 25000 -18.6  -1.5  245  37 19   6.9   3.8 | -18.5  -1.3  245  38 19   6.8   3.7
 24000 -16.5   2.3  245  35 18   6.8   3.8 | -16.5   2.3  245  36 19   6.7   3.7
 23000 -14.5   5.9  250  34 18   6.8   3.8 | -14.5   5.9  250  35 18   6.7   3.7
 22000 -12.4   9.7  250  34 17   7.0   3.8 | -12.5   9.5  250  33 17   6.8   3.8
 21000 -10.2  13.6  245  32 17   7.4   4.0 | -10.3  13.5  250  32 16   7.3   4.0
 20000  -8.0  17.6  240  31 16   7.4   4.0 |  -8.1  17.4  245  31 16   7.3   4.0
 19500  -6.9  19.6  235  31 16   7.5   4.1 |  -7.0  19.4  245  30 16   7.4   4.1
 19000  -5.9  21.4  235  30 15   6.2   3.4 |  -6.0  21.2  240  30 15   6.5   3.5
 18500  -5.0  23.0  230  29 15   6.2   3.4 |  -4.5  23.9  240  29 15   6.5   3.6
 18000  -4.0  24.8  230  28 14   6.0   3.3 |  -3.6  25.5  240  29 15   6.0   3.3
 17500  -2.8  27.0  230  25 13   5.7   3.1 |  -2.7  27.1  235  27 14   6.1   3.3
 17000  -1.9  28.6  225  23 12   6.5   3.6 |  -1.8  28.8  235  25 13   6.9   3.8
 16500  -0.8  30.6  230  21 11   8.1   4.5 |  -0.6  30.9  240  24 12   8.2   4.5
 16000   0.5  32.9  235  19 10   8.2   4.5 |   0.6  33.1  245  22 12   8.4   4.6
 15500   1.6  34.9  240  17  9   7.6   4.2 |   1.7  35.1  250  23 12   6.5   3.6
 15000   2.7  36.9  245  17  9   7.7   4.2 |   2.7  36.9  255  24 12   6.9   3.8
 14500   3.8  38.8  255  18  9   6.4   3.5 |   3.5  38.3  255  25 13   4.0   2.2
 14000   4.7  40.5  260  19 10   6.2   3.4 |   3.9  39.0  260  24 12   3.7   2.1
 13500   5.6  42.1  265  20 10   6.4   3.5 |   4.4  39.9  260  23 12   5.3   2.9
 13000   6.5  43.7  265  20 10   6.6   3.6 |   5.3  41.5  260  19 10   6.5   3.5
 12500   7.4  45.3  270  19 10   6.8   3.7 |   6.2  43.2  255  16  8   7.8   4.3
 12000   8.4  47.1  270  18  9   7.0   3.8 |   7.6  45.7  250  13  7   9.6   5.3
 11500   9.4  48.9  270  17  9   6.9   3.8 |   9.0  48.2  245  11  6   9.1   5.0
 11000  10.4  50.7  265  15  8   6.2   3.4 |  10.3  50.5  240  10  5   7.7   4.2
 10500  11.3  52.3  260  13  7   4.6   2.5 |  11.5  52.7  235   9  5   4.6   2.5
 10250  11.5  52.7  255  12  6   4.1   2.2 |  11.7  53.1  230   9  5   4.5   2.5
 10000  12.0  53.6  255  11  6   7.2   3.9 |  12.3  54.1  225   9  5   9.8   5.4
  9750  12.5  54.5  250  10  5   8.1   4.4 |  13.0  55.4  220   9  5  10.3   5.6
  9500  13.0  55.4  245   9  5   6.3   3.5 |  13.7  56.7  220   9  4   7.6   4.2
  9250  13.4  56.1  245   8  4   3.4   1.9 |  14.0  57.2  215   8  4   3.9   2.1
  9000  13.6  56.5  250   8  4   4.2   2.3 |  14.3  57.7  205   8  4   4.5   2.5
  8750  13.9  57.0  255   7  4   5.6   3.1 |  14.7  58.5  200   7  4   5.7   3.1
  8500  14.3  57.7  265   6  3   4.2   2.3 |  15.0  59.0  195   6  3   3.5   1.9
  8250  14.5  58.1  275   6  3   2.9   1.6 |  15.1  59.2  170   4  2   0.9   0.5
  8000  14.7  58.5  290   6  3   3.3   1.8 |  15.1  59.2  135   4  2   3.3   1.8
  7750  15.0  59.0  300   6  3   3.8   2.1 |  15.4  59.7  105   5  2   6.4   3.5
  7500  15.2  59.4  305   6  3   2.7   1.5 |  15.9  60.6  090   6  3   9.0   4.9
  7250  15.3  59.5  310   5  3   1.9   1.0 |  16.7  62.1  090   6  3  10.1   5.6
  7000  15.4  59.7  315   5  2   1.8   1.0 |  17.4  63.3  090   6  3   9.9   5.4
  6750  15.6  60.1  320   4  2   3.6   2.0 |  18.1  64.6  090   6  3  10.0   5.5
  6500  16.0  60.8  325   3  1   6.5   3.6 |  18.9  66.0  090   6  3  10.2   5.6
  6250  16.4  61.5  360   1  1   6.7   3.7 |  19.7  67.5  085   6  3   9.8   5.4
  6000  16.9  62.4  080   2  1   7.6   4.2 |  20.4  68.7  085   6  3  11.4   6.2
  5750  17.5  63.5  095   3  1  12.9   7.1 |  21.5  70.7  085   6  3  18.0   9.9
  5500  18.7  65.7  095   3  1  18.6  10.2 |  23.0  73.4  085   6  3  24.2  13.3

           07/28/2015 at 1500 MDT          |       07/28/2015 at 1800 MDT
                                           |
K index... +19.2  LI... +1.5               | K index... +23.8  LI... -1.4
CAPE... 0.0  CIN... -0.6                   | CAPE... +40.0  CIN... -73.7
                                           |
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 -64.9 -84.8  235  46 24   1.0   0.5 | -65.3 -85.5  240  45 23   1.3   0.7
 45000 -61.1 -78.0  235  64 33   6.0   3.3 | -61.0 -77.8  240  61 32   6.3   3.5
 40000 -51.4 -60.5  235  66 34   7.4   4.1 | -50.8 -59.4  235  63 33   7.2   4.0
 38000 -47.0 -52.6  235  66 34   7.4   4.0 | -46.5 -51.7  235  65 33   7.2   4.0
 36000 -42.6 -44.7  235  65 34   7.3   4.0 | -42.2 -44.0  235  66 34   7.3   4.0
 34000 -38.3 -36.9  235  61 31   7.1   3.9 | -37.7 -35.9  235  63 33   7.5   4.1
 32000 -34.1 -29.4  235  56 29   6.9   3.8 | -33.2 -27.8  240  61 31   7.5   4.1
 30000 -29.4 -20.9  235  50 26   7.9   4.4 | -28.9 -20.0  240  54 28   7.2   4.0
 29000 -27.1 -16.8  230  47 24   7.9   4.4 | -26.2 -15.2  240  50 26   7.2   4.0
 28000 -24.2 -11.6  230  43 22   6.1   3.4 | -24.1 -11.4  240  47 24   6.3   3.4
 27000 -22.3  -8.1  235  40 21   6.4   3.5 | -22.2  -8.0  245  44 23   6.4   3.5
 26000 -20.4  -4.7  240  38 19   6.4   3.5 | -20.2  -4.4  250  42 21   6.4   3.5
 25000 -18.4  -1.1  245  36 18   6.8   3.8 | -18.3  -0.9  255  39 20   6.5   3.5
 24000 -16.2   2.8  245  35 18   7.4   4.1 | -16.4   2.5  255  39 20   6.6   3.6
 23000 -14.0   6.8  245  34 18   7.4   4.1 | -14.4   6.1  255  38 19   6.6   3.6
 22000 -11.8  10.8  250  34 17   6.7   3.7 | -12.5   9.5  260  37 19   5.9   3.3
 21000 -10.0  14.0  250  34 18   6.0   3.3 | -11.0  12.2  255  35 18   5.4   2.9
 20000  -8.2  17.2  245  35 18   6.1   3.3 |  -9.5  14.9  255  33 17   5.7   3.1
 19500  -7.3  18.9  245  36 18   6.1   3.4 |  -8.7  16.3  255  33 17   5.8   3.2
 19000  -6.5  20.3  250  36 18   5.4   3.0 |  -7.7  18.1  250  31 16   9.2   5.1
 18500  -5.7  21.7  250  35 18   5.7   3.1 |  -6.4  20.5  250  29 15   9.0   4.9
 18000  -4.9  23.2  250  35 18   5.9   3.3 |  -5.2  22.6  250  27 14   8.4   4.6
 17500  -4.1  24.6  250  33 17   6.1   3.4 |  -4.0  24.8  245  26 13   7.9   4.4
 17000  -3.3  26.1  250  31 16   6.3   3.4 |  -2.8  27.0  245  24 13   7.9   4.3
 16500  -2.3  27.9  250  30 15   8.3   4.6 |  -1.6  29.1  245  23 12   8.1   4.5
 16000  -1.1  30.0  250  27 14   8.1   4.5 |  -0.4  31.3  245  22 11   8.1   4.5
 15500   0.1  32.2  245  25 13   9.0   4.9 |   1.4  34.5  240  20 10   7.9   4.4
 15000   2.2  36.0  245  23 12   9.5   5.2 |   2.5  36.5  235  20 10   8.1   4.4
 14500   3.5  38.3  245  21 11   7.3   4.0 |   3.6  38.5  230  19 10   6.7   3.7
 14000   4.6  40.3  240  20 10   7.3   4.0 |   4.6  40.3  220  19 10   6.8   3.7
 13500   5.6  42.1  240  18  9   7.6   4.2 |   5.5  41.9  215  19 10   7.0   3.9
 13000   6.8  44.2  235  17  9   7.7   4.2 |   6.5  43.7  210  18  9   7.1   3.9
 12500   7.9  46.2  230  15  8   7.1   3.9 |   7.5  45.5  200  17  9   7.0   3.8
 12000   8.8  47.8  225  14  7   6.6   3.6 |   8.5  47.3  195  14  7   6.8   3.7
 11500   9.8  49.6  220  13  6   6.0   3.3 |   9.5  49.1  190  11  6   6.2   3.4
 11000  10.5  50.9  210  10  5   4.9   2.7 |  10.3  50.5  165   8  4   5.3   2.9
 10500  11.2  52.2  190   8  4   1.2   0.6 |  11.2  52.2  125   7  4   2.8   1.5
 10250  11.2  52.2  185   7  4   3.5   1.9 |  11.4  52.5  120   7  4   6.5   3.6
 10000  11.8  53.2  165   6  3  10.2   5.6 |  12.2  54.0  115   8  4  12.5   6.8
  9750  12.4  54.3  135   6  3   8.6   4.7 |  13.1  55.6  105   8  4  11.4   6.3
  9500  13.0  55.4  115   8  4   8.5   4.7 |  13.9  57.0  100   9  4   9.5   5.2
  9250  13.6  56.5  110   8  4   8.3   4.5 |  14.5  58.1  100   9  5   7.8   4.3
  9000  14.3  57.7  110   8  4  10.2   5.6 |  15.2  59.4  100   9  5  10.7   5.9
  8750  15.1  59.2  110   8  4  11.3   6.2 |  16.0  60.8  100   9  5  11.8   6.5
  8500  15.9  60.6  105   8  4  10.1   5.5 |  16.9  62.4  095   9  5  10.5   5.7
  8250  16.6  61.9  105   8  4   9.3   5.1 |  17.6  63.7  095   9  5   9.6   5.3
  8000  17.3  63.1  105   8  4   9.8   5.4 |  18.3  64.9  095   9  5   9.8   5.4
  7750  18.1  64.6  105   8  4  10.1   5.6 |  19.0  66.2  095   9  5   9.8   5.4
  7500  18.8  65.8  105   8  4  10.1   5.5 |  19.8  67.6  090   9  5   9.9   5.4
  7250  19.6  67.3  105   8  4  10.2   5.6 |  20.5  68.9  090   9  5   9.9   5.4
  7000  20.4  68.7  105   8  4  10.0   5.5 |  21.3  70.3  090   9  5  10.0   5.5
  6750  21.1  70.0  105   8  4  10.3   5.6 |  22.0  71.6  090   9  5  10.1   5.6
  6500  21.9  71.4  105   8  4  10.8   5.9 |  22.8  73.0  090   9  5  10.1   5.5
  6250  22.7  72.9  100   8  4  11.3   6.2 |  23.5  74.3  090   9  5  10.1   5.6
  6000  23.5  74.3  100   8  4   9.6   5.3 |  24.3  75.7  090   9  5   9.8   5.4
  5750  24.3  75.7  100   8  4  15.3   8.4 |  25.1  77.2  085   9  5  12.8   7.0
  5500  26.0  78.8  100   8  4  29.5  16.2 |  26.2  79.2  085   9  4  18.7  10.2
________________________________________________________________________________

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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