Soaring Guidance
Issued by NWS Denver/Boulder, CO

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980
UXUS97 KBOU 150121
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1821 MST Tuesday, November 14, 2017

This forecast is for Wednesday, November 15, 2017:

If the trigger temperature of 47.5 F/8.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 268 ft/min (1.4 m/s)
   Maximum height of thermals.................. 10084 ft MSL (4777 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... 1100 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9406 ft MSL (4099 ft AGL)
Thermal soaring outlook for Thursday 11/16..... Fair

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 11946 ft MSL (6639 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 45140 ft MSL (39833 ft AGL)
Wave soaring outlook for Thursday 11/16........ Fair

Remarks...

Sunrise/Sunset.................... 06:44:33 / 16:43:37 MST
Total possible sunshine........... 9 hr 59 min 4 sec (599 min 4 sec)
Altitude of sun at 11:44:17 MST... 31.60 degrees

Upper air data from numerical model forecast valid on 11/15/2017 at 0500 MST

Freezing level.................. 6601 ft MSL (1294 ft AGL)
Convective condensation level... 16445 ft MSL (11138 ft AGL)
Lifted condensation level....... 12307 ft MSL (7000 ft AGL)
Lifted index.................... +8.5
K index......................... -30.1

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  -63.7 -82.7   285   97   50   1.8   1.0      M     M       M      M    M
 45000  -61.0 -77.8   290  116   60  -0.1  -0.1      M     M       M      M    M
 40000  -61.0 -77.8   285  108   55  -0.1  -0.0      M     M       M      M    M
 38000  -59.3 -74.7   290  102   52   4.8   2.6      M     M       M      M    M
 36000  -56.4 -69.5   290   94   48   4.8   2.6      M     M       M      M    M
 34000  -52.9 -63.2   295   89   46   8.7   4.8      M     M       M      M    M
 32000  -47.6 -53.7   295   87   45   8.8   4.8      M     M       M      M    M
 30000  -41.8 -43.2   290   83   43   8.6   4.7   34.2  93.6    16.6      M    M
 29000  -39.2 -38.6   290   80   41   8.6   4.7   33.7  92.7    16.4      M    M
 28000  -36.6 -33.9   290   77   40   8.6   4.7   33.3  92.0    16.3      M    M
 27000  -34.1 -29.4   290   75   39   8.0   4.4   32.9  91.1    16.1      M    M
 26000  -31.7 -25.1   290   74   38   8.0   4.4   32.1  89.8    15.7      M    M
 25000  -29.3 -20.7   290   72   37   8.0   4.4   31.5  88.7    15.4      M    M
 24000  -27.0 -16.6   290   70   36   6.6   3.6   30.9  87.5    15.0      M    M
 23000  -25.1 -13.2   290   64   33   6.4   3.5   29.5  85.2    14.1      M    M
 22000  -23.1  -9.6   290   58   30   6.4   3.5   28.4  83.0    13.3      M    M
 21000  -21.2  -6.2   290   52   27   6.2   3.4   27.2  80.9    12.5      M    M
 20000  -19.4  -2.9   290   47   24   6.2   3.4   25.9  78.6    11.6      M    M
 19500  -18.4  -1.1   290   44   23   6.2   3.4   25.3  77.5    11.1      M    M
 19000  -17.5   0.5   290   41   21   6.0   3.3   24.7  76.5    10.7      M    M
 18500  -16.4   2.5   290   39   20   8.6   4.7   24.3  75.7    10.4      M    M
 18000  -15.1   4.8   290   38   19   8.7   4.8   24.1  75.3    10.3      M    M
 17500  -13.8   7.2   290   36   19   8.8   4.8   23.9  75.0    10.2      M    M
 17000  -12.5   9.5   290   35   18   8.9   4.9   23.7  74.7    10.1      M    M
 16500  -11.1  12.0   290   34   18   9.0   5.0   23.6  74.5    10.0      M    M
 16000   -9.3  15.3   290   33   17   7.9   4.3   23.2  73.8     9.8      M    M
 15500   -8.1  17.4   290   33   17   7.8   4.3   22.9  73.2     9.6      M    M
 15000   -7.0  19.4   290   32   16   7.3   4.0   22.5  72.5     9.3      M    M
 14500   -5.9  21.4   295   31   16   7.4   4.0   22.1  71.8     8.9      M    M
 14000   -4.9  23.2   295   30   16   6.1   3.3   21.6  70.9     8.5      M    M
 13500   -4.0  24.8   295   29   15   6.4   3.5   21.0  69.8     8.0      M    M
 13000   -3.2  26.2   295   28   15   4.3   2.3   20.3  68.6     7.4      M    M
 12500   -2.5  27.5   295   27   14   4.4   2.4   19.4  67.0     6.6      M    M
 12000   -2.0  28.4   290   25   13   2.1   1.2   18.4  65.1     5.7      M    M
 11500   -1.8  28.8   290   23   12   2.2   1.2   17.1  62.9     4.5      M    M
 11000   -1.7  28.9   285   21   11  -1.5  -0.8   15.7  60.3     3.1      M    M
 10500   -2.0  28.4   280   18    9  -2.0  -1.1   13.9  57.0     1.3      M    M
 10250   -2.2  28.0   280   17    9  -0.9  -0.5   13.0  55.3     0.5      M    M
 10000   -2.3  27.9   275   16    8  -1.8  -1.0   12.1  53.8    -0.3    266  1.4
  9750   -2.6  27.3   270   15    8  -4.8  -2.7   11.1  51.9    -1.4    268  1.4
  9500   -3.1  26.4   260   13    7  -6.0  -3.3    9.9  49.8    -2.6    275  1.4
  9250   -3.5  25.7   245   11    6  -2.2  -1.2    8.7  47.7    -3.8    281  1.4
  9000   -3.5  25.7   245    8    4   0.9   0.5    8.0  46.4    -4.5    274  1.4
  8750   -3.5  25.7   245    5    3   2.2   1.2    7.3  45.2    -5.2    264  1.3
  8500   -3.2  26.2   315    1    1   4.7   2.6    6.8  44.3    -5.7    249  1.3
  8250   -2.8  27.0   035    4    2   5.6   3.1    6.5  43.7    -6.1    230  1.2
  8000   -2.4  27.7   040    8    4   6.4   3.5    6.2  43.2    -6.4    209  1.1
  7750   -1.9  28.6   040   11    6   5.8   3.2    5.9  42.7    -6.7    188  1.0
  7500   -1.5  29.3   045   13    7   5.3   2.9    5.6  42.1    -7.0    169  0.9
  7250   -1.1  30.0   050   12    6   5.5   3.0    5.3  41.5    -7.4    150  0.8
  7000   -0.7  30.7   060   11    5   5.4   2.9    4.9  40.9    -7.7    131  0.7
  6750   -0.4  31.3   070   10    5   5.7   3.1    4.6  40.3    -8.1    112  0.6
  6500    0.1  32.2   080    8    4   7.7   4.2    4.4  39.8    -8.4     90  0.5
  6250    0.7  33.3   095    6    3   8.5   4.6    4.3  39.7    -8.5     64  0.3
  6000    1.4  34.5   120    5    3   8.9   4.9    4.2  39.5    -8.6     38  0.2
  5750    1.9  35.4   155    5    3   3.3   1.8    4.0  39.2    -8.8     14  0.1
  5500    1.7  35.1   175    4    2  -8.2  -4.5    3.1  37.5    -9.8     13  0.1

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

           11/15/2017 at 0800 MST          |       11/15/2017 at 1100 MST
                                           |
K index... -36.8  LI... +6.0               | K index... -31.6  LI... +5.7
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -63.7 -82.7  285  97 50   2.1   1.2 | -63.9 -83.0  285  90 46   1.3   0.7
 45000 -60.6 -77.1  290 119 61  -1.8  -1.0 | -62.0 -79.6  290 113 58   0.2   0.1
 40000 -63.0 -81.4  285  94 49  -1.6  -0.9 | -61.5 -78.7  285  91 47   0.3   0.2
 38000 -60.5 -76.9  285  85 44   7.2   4.0 | -59.0 -74.2  285  84 43   6.2   3.4
 36000 -56.2 -69.2  285  76 39   7.2   4.0 | -55.3 -67.5  285  76 39   6.2   3.4
 34000 -51.7 -61.1  290  70 36   8.0   4.4 | -51.3 -60.3  290  71 36   7.6   4.2
 32000 -46.9 -52.4  290  69 35   8.0   4.4 | -46.2 -51.2  290  68 35   7.7   4.2
 30000 -41.5 -42.7  290  67 35   8.2   4.5 | -41.4 -42.5  290  63 33   8.3   4.6
 29000 -39.0 -38.2  290  67 34   8.2   4.5 | -38.9 -38.0  290  59 31   8.3   4.6
 28000 -36.6 -33.9  290  66 34   8.2   4.5 | -36.4 -33.5  290  56 29   8.4   4.6
 27000 -34.0 -29.2  290  65 33   9.0   5.0 | -33.8 -28.8  285  53 27   8.7   4.8
 26000 -31.3 -24.3  285  63 33   9.0   4.9 | -31.2 -24.2  285  53 27   8.7   4.8
 25000 -28.7 -19.7  285  62 32   9.0   4.9 | -28.6 -19.5  285  53 27   8.7   4.8
 24000 -26.2 -15.2  285  61 31   5.6   3.1 | -26.1 -15.0  285  53 27   7.6   4.2
 23000 -24.5 -12.1  285  57 29   5.6   3.1 | -23.9 -11.0  285  51 26   7.6   4.2
 22000 -22.9  -9.2  285  53 28   5.6   3.1 | -21.6  -6.9  285  49 25   7.6   4.2
 21000 -21.0  -5.8  285  49 25   7.6   4.2 | -19.5  -3.1  285  47 24   5.5   3.0
 20000 -18.7  -1.7  285  45 23   7.5   4.1 | -17.9  -0.2  285  44 23   5.7   3.1
 19500 -17.6   0.3  285  43 22   7.5   4.1 | -17.0   1.4  285  43 22   5.7   3.1
 19000 -16.5   2.3  285  41 21   7.7   4.2 | -16.2   2.8  280  42 22   5.5   3.0
 18500 -15.4   4.3  280  39 20   6.5   3.6 | -15.2   4.6  280  40 21   8.2   4.5
 18000 -14.4   6.1  280  37 19   6.6   3.6 | -13.9   7.0  280  38 20   8.3   4.5
 17500 -13.4   7.9  280  36 18   7.5   4.1 | -12.6   9.3  285  36 18   8.2   4.5
 17000 -12.1  10.2  280  34 18   8.6   4.7 | -11.4  11.5  280  34 18   7.9   4.4
 16500 -10.8  12.6  280  33 17   8.7   4.8 |  -9.5  14.9  280  32 17   7.3   4.0
 16000  -9.0  15.8  280  31 16   7.9   4.3 |  -8.5  16.7  280  31 16   6.8   3.7
 15500  -7.8  18.0  280  30 16   8.0   4.4 |  -7.5  18.5  280  29 15   6.9   3.8
 15000  -6.6  20.1  280  30 15   8.4   4.6 |  -6.4  20.5  275  28 14   7.5   4.1
 14500  -5.3  22.5  280  29 15   8.5   4.6 |  -5.3  22.5  275  26 13   7.5   4.1
 14000  -4.1  24.6  285  28 14   7.3   4.0 |  -4.2  24.4  275  24 13   6.8   3.7
 13500  -3.0  26.6  285  27 14   7.5   4.1 |  -3.2  26.2  275  23 12   6.9   3.8
 13000  -2.0  28.4  285  26 13   6.1   3.3 |  -2.2  28.0  275  21 11   6.1   3.3
 12500  -1.1  30.0  285  25 13   6.3   3.4 |  -1.3  29.7  275  19 10   6.1   3.4
 12000  -0.3  31.5  285  23 12   4.5   2.5 |  -0.4  31.3  270  18  9   5.7   3.1
 11500   0.4  32.7  285  22 11   4.7   2.6 |   0.4  32.7  270  16  8   5.9   3.2
 11000   0.9  33.6  285  20 10   1.8   1.0 |   1.1  34.0  265  14  7   3.1   1.7
 10500   1.1  34.0  280  18  9   1.7   0.9 |   1.5  34.7  260  13  6   3.1   1.7
 10250   1.2  34.2  280  17  9   1.2   0.7 |   1.7  35.1  255  12  6   1.8   1.0
 10000   1.2  34.2  275  17  9  -1.1  -0.6 |   1.8  35.2  255  11  6   0.8   0.4
  9750   1.0  33.8  270  16  8  -3.2  -1.8 |   1.9  35.4  245  11  6   1.3   0.7
  9500   0.7  33.3  265  15  8  -2.9  -1.6 |   1.9  35.4  240  11  6   1.6   0.9
  9250   0.4  32.7  260  14  7  -4.7  -2.6 |   2.0  35.6  230  11  5   0.4   0.2
  9000  -0.1  31.8  250  13  7  -6.5  -3.5 |   1.9  35.4  225  10  5  -0.6  -0.3
  8750  -0.6  30.9  240  12  6  -7.3  -4.0 |   1.9  35.4  215  10  5   0.2   0.1
  8500  -1.3  29.7  225  10  5  -6.7  -3.7 |   1.9  35.4  205  11  5   0.6   0.3
  8250  -1.6  29.1  205   9  5  -0.7  -0.4 |   1.9  35.4  195  11  6   1.3   0.7
  8000  -1.5  29.3  190   7  4   1.4   0.8 |   2.0  35.6  190  12  6   1.9   1.0
  7750  -1.5  29.3  160   7  3   2.7   1.5 |   2.1  35.8  180  13  7   1.2   0.6
  7500  -1.1  30.0  145   6  3   5.7   3.1 |   2.1  35.8  175  14  7   2.9   1.6
  7250  -0.7  30.7  145   7  4   5.9   3.2 |   2.5  36.5  165  13  7   5.4   3.0
  7000  -0.3  31.5  150   7  4   5.6   3.1 |   2.8  37.0  160  12  6   5.0   2.8
  6750   0.1  32.2  155   8  4   6.7   3.7 |   3.2  37.8  150  11  6   6.5   3.6
  6500   0.7  33.3  160   8  4   7.1   3.9 |   3.8  38.8  150  11  5   9.5   5.2
  6250   1.1  34.0  170   9  5   7.2   4.0 |   4.6  40.3  150  10  5   9.7   5.3
  6000   1.6  34.9  175  10  5   5.0   2.7 |   5.3  41.5  145  10  5  11.2   6.1
  5750   1.8  35.2  175  10  5   0.7   0.4 |   6.3  43.3  145   9  5  15.6   8.6
  5500   1.9  35.4  175   7  3   1.2   0.6 |   7.6  45.7  145   9  4  17.7   9.7

           11/15/2017 at 1400 MST          |       11/15/2017 at 1700 MST
                                           |
K index... -27.8  LI... +5.6               | K index... -13.5  LI... +6.3
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -63.6 -82.5  285  86 44   1.1   0.6 | -64.7 -84.5  285  90 46   1.6   0.9
 45000 -61.9 -79.4  285 107 55   0.5   0.3 | -62.2 -80.0  285 106 55   1.1   0.6
 40000 -61.1 -78.0  285  90 46   0.6   0.3 | -60.5 -76.9  290  90 46   1.2   0.7
 38000 -58.6 -73.5  285  83 43   6.0   3.3 | -58.0 -72.4  290  83 42   5.6   3.1
 36000 -55.1 -67.2  285  77 40   6.0   3.3 | -54.7 -66.5  285  75 39   5.6   3.1
 34000 -51.1 -60.0  285  70 36   8.0   4.4 | -50.7 -59.3  285  68 35   8.6   4.7
 32000 -45.6 -50.1  280  62 32   8.1   4.4 | -44.9 -48.8  285  63 32   8.6   4.7
 30000 -40.7 -41.3  275  56 29   8.4   4.6 | -39.8 -39.6  280  58 30   8.2   4.5
 29000 -38.2 -36.8  275  54 28   8.4   4.6 | -37.3 -35.1  280  55 29   8.2   4.5
 28000 -35.7 -32.3  275  52 27   8.4   4.6 | -34.9 -30.8  275  53 27   8.2   4.5
 27000 -33.2 -27.8  275  50 26   7.5   4.1 | -32.5 -26.5  275  51 26   7.6   4.1
 26000 -31.0 -23.8  275  47 24   7.6   4.1 | -30.2 -22.4  275  49 25   7.6   4.2
 25000 -28.7 -19.7  275  45 23   7.6   4.2 | -28.0 -18.4  270  47 24   7.6   4.2
 24000 -26.5 -15.7  275  43 22   7.7   4.2 | -25.7 -14.3  270  46 24   7.3   4.0
 23000 -24.2 -11.6  275  41 21   7.8   4.3 | -23.5 -10.3  270  43 22   7.3   4.0
 22000 -21.9  -7.4  280  40 20   7.8   4.3 | -21.4  -6.5  265  41 21   7.3   4.0
 21000 -19.6  -3.3  280  38 20   7.0   3.8 | -19.3  -2.7  265  38 20   6.6   3.6
 20000 -17.5   0.5  275  38 20   7.1   3.9 | -17.3   0.9  270  35 18   6.7   3.7
 19500 -16.5   2.3  275  38 19   7.1   3.9 | -16.3   2.7  270  33 17   6.7   3.7
 19000 -15.4   4.3  275  38 19   7.1   3.9 | -15.3   4.5  270  31 16   6.7   3.7
 18500 -14.4   6.1  275  37 19   7.4   4.0 | -14.3   6.3  270  29 15   6.5   3.6
 18000 -13.2   8.2  275  35 18   7.4   4.1 | -13.3   8.1  270  26 13   6.5   3.6
 17500 -12.1  10.2  275  34 17   7.2   4.0 | -12.3   9.9  270  23 12   6.7   3.7
 17000 -10.4  13.3  275  29 15   7.1   3.9 | -10.6  12.9  275  20 10   7.3   4.0
 16500  -9.3  15.3  280  25 13   7.3   4.0 |  -9.5  14.9  275  18  9   7.9   4.3
 16000  -8.2  17.2  280  25 13   7.5   4.1 |  -8.2  17.2  280  22 11   8.5   4.7
 15500  -7.0  19.4  280  25 13   7.4   4.1 |  -6.9  19.6  280  26 13   8.3   4.5
 15000  -6.0  21.2  275  24 13   6.8   3.7 |  -5.9  21.4  280  27 14   4.9   2.7
 14500  -4.9  23.2  275  24 12   6.9   3.8 |  -5.2  22.6  275  26 14   5.1   2.8
 14000  -3.9  25.0  275  23 12   6.6   3.6 |  -4.4  24.1  275  26 13   5.7   3.1
 13500  -2.9  26.8  275  22 11   6.6   3.6 |  -3.5  25.7  270  24 12   5.6   3.1
 13000  -1.9  28.6  275  21 11   6.7   3.7 |  -2.6  27.3  270  23 12   7.0   3.9
 12500  -0.9  30.4  270  19 10   6.7   3.7 |  -1.6  29.1  270  21 11   7.2   4.0
 12000   0.1  32.2  270  18  9   6.7   3.7 |  -0.5  31.1  265  19 10   6.9   3.8
 11500   1.1  34.0  270  16  8   6.8   3.8 |   0.5  32.9  265  16  8   6.8   3.7
 11000   2.0  35.6  270  14  7   5.4   3.0 |   1.5  34.7  265  14  7   7.2   4.0
 10500   2.8  37.0  270  12  6   5.8   3.2 |   2.5  36.5  260  12  6   7.9   4.3
 10250   3.1  37.6  265  10  5   2.4   1.3 |   3.1  37.6  260  11  6   5.2   2.9
 10000   3.2  37.8  265  10  5   1.5   0.8 |   3.3  37.9  260  11  6   4.8   2.6
  9750   3.4  38.1  265   9  5   4.2   2.3 |   3.8  38.8  260  10  5   7.0   3.8
  9500   3.7  38.7  265   8  4   3.8   2.1 |   4.3  39.7  260  10  5   6.9   3.8
  9250   3.9  39.0  260   8  4   3.1   1.7 |   4.8  40.6  260   9  5   5.0   2.8
  9000   4.1  39.4  260   7  4   1.3   0.7 |   5.0  41.0  260   9  4   2.4   1.3
  8750   4.1  39.4  255   7  3   0.8   0.5 |   5.2  41.4  260   8  4   2.5   1.4
  8500   4.2  39.6  245   6  3   0.8   0.4 |   5.4  41.7  260   8  4   3.0   1.6
  8250   4.2  39.6  230   5  3   0.9   0.5 |   5.6  42.1  265   7  4   0.8   0.4
  8000   4.2  39.6  200   4  2   1.5   0.8 |   5.5  41.9  260   6  3  -0.8  -0.5
  7750   4.3  39.7  170   4  2   3.8   2.1 |   5.5  41.9  255   4  2   0.9   0.5
  7500   4.7  40.5  155   4  2   6.5   3.6 |   5.6  42.1  250   3  1   2.9   1.6
  7250   5.2  41.4  150   4  2   8.7   4.8 |   5.9  42.6  245   2  1   6.2   3.4
  7000   5.9  42.6  145   4  2   9.7   5.3 |   6.4  43.5  240   1  1   7.6   4.1
  6750   6.6  43.9  145   4  2   8.5   4.6 |   6.9  44.4  220   1  0   7.6   4.2
  6500   7.2  45.0  145   4  2   9.5   5.2 |   7.5  45.5  190   1  0   8.6   4.7
  6250   8.0  46.4  145   3  2  11.2   6.2 |   8.2  46.8  000   0  0   8.7   4.8
  6000   8.8  47.8  140   3  2  10.3   5.7 |   8.8  47.8  025   1  0   9.3   5.1
  5750   9.6  49.3  140   3  2  12.0   6.6 |   9.5  49.1  020   1  1   6.6   3.6
  5500  10.7  51.3  140   3  2  16.5   9.1 |   9.7  49.5  015   2  1  -0.0  -0.0
________________________________________________________________________________

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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