Soaring Guidance
Issued by NWS Denver/Boulder, CO

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UXUS97 KBOU 120033
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1732 MST Saturday, November 11, 2017

This forecast is for Sunday, November 12, 2017:

If the trigger temperature of 50.8 F/10.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 375 ft/min (1.9 m/s)
   Maximum height of thermals.................. 10676 ft MSL (5369 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 C
Time of trigger temperature.................... 1215 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................. 8904 ft MSL (3597 ft AGL)
Thermal soaring outlook for Monday 11/13....... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 13926 ft MSL (8619 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 40032 ft MSL (34725 ft AGL)
Wave soaring outlook for Monday 11/13.......... Fair

Remarks...

Sunrise/Sunset.................... 06:41:08 / 16:46:04 MST
Total possible sunshine........... 10 hr 4 min 56 sec (604 min 56 sec)
Altitude of sun at 11:43:49 MST... 32.38 degrees

Upper air data from numerical model forecast valid on 11/12/2017 at 0500 MST

Freezing level.................. 8197 ft MSL (2890 ft AGL)
Convective condensation level... 16715 ft MSL (11408 ft AGL)
Lifted condensation level....... 12276 ft MSL (6969 ft AGL)
Lifted index.................... +7.8
K index......................... -18.2

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  -63.0 -81.4   285   67   35   2.9   1.6      M     M       M      M    M
 45000  -58.9 -74.0   290   84   43   1.4   0.7      M     M       M      M    M
 40000  -56.8 -70.2   290   90   46   1.4   0.8      M     M       M      M    M
 38000  -55.1 -67.2   290   88   45   3.5   1.9      M     M       M      M    M
 36000  -53.0 -63.4   290   84   43   3.5   1.9      M     M       M      M    M
 34000  -50.2 -58.4   290   79   41   6.6   3.6      M     M       M      M    M
 32000  -45.8 -50.4   295   69   35   6.6   3.6      M     M       M      M    M
 30000  -41.4 -42.5   295   61   31   8.2   4.5   34.7  94.5    16.5      M    M
 29000  -38.9 -38.0   290   57   29   8.2   4.5   34.1  93.3    16.2      M    M
 28000  -36.5 -33.7   290   54   28   8.2   4.5   33.6  92.4    16.0      M    M
 27000  -34.1 -29.4   290   51   26   7.5   4.1   32.9  91.3    15.7      M    M
 26000  -31.8 -25.2   290   48   25   7.6   4.1   32.0  89.6    15.2      M    M
 25000  -29.5 -21.1   290   46   24   7.6   4.1   31.2  88.2    14.7      M    M
 24000  -27.2 -17.0   285   44   23   7.9   4.4   30.5  86.9    14.3      M    M
 23000  -24.8 -12.6   285   42   22   7.9   4.3   29.7  85.5    13.9      M    M
 22000  -22.5  -8.5   285   41   21   7.9   4.3   29.1  84.4    13.5      M    M
 21000  -20.2  -4.4   285   38   20   7.3   4.0   28.4  83.1    13.1      M    M
 20000  -17.9  -0.2   285   36   18   7.4   4.0   27.5  81.5    12.5      M    M
 19500  -16.8   1.8   285   35   18   7.4   4.0   27.1  80.8    12.2      M    M
 19000  -15.7   3.7   285   33   17   7.3   4.0   26.7  80.1    12.0      M    M
 18500  -14.6   5.7   285   32   17   7.6   4.2   26.4  79.4    11.7      M    M
 18000  -13.5   7.7   290   31   16   7.6   4.2   26.0  78.8    11.4      M    M
 17500  -12.3   9.9   290   30   16   7.7   4.2   25.6  78.1    11.2      M    M
 17000  -10.6  12.9   295   29   15   7.9   4.3   25.1  77.2    10.8      M    M
 16500   -9.4  15.1   295   28   14   6.2   3.4   24.7  76.5    10.6      M    M
 16000   -8.6  16.5   295   27   14   5.4   3.0   24.0  75.2    10.0      M    M
 15500   -7.8  18.0   295   26   13   4.6   2.5   23.3  73.9     9.4      M    M
 15000   -7.3  18.9   295   24   13   3.0   1.6   22.2  72.0     8.5      M    M
 14500   -6.9  19.6   290   23   12   3.0   1.6   21.1  70.0     7.5      M    M
 14000   -6.5  20.3   290   22   11   1.9   1.1   19.9  67.8     6.4      M    M
 13500   -6.2  20.8   285   20   10   2.0   1.1   18.6  65.5     5.3      M    M
 13000   -5.9  21.4   280   19   10   2.7   1.5   17.4  63.3     4.1      M    M
 12500   -5.6  21.9   275   18    9   2.6   1.4   16.3  61.3     3.0      M    M
 12000   -5.1  22.8   270   17    9   4.8   2.6   15.3  59.5     2.1      M    M
 11500   -4.5  23.9   260   16    8   4.7   2.6   14.5  58.0     1.2      M    M
 11000   -3.8  25.2   250   16    8   5.3   2.9   13.7  56.6     0.4      M    M
 10500   -3.1  26.4   240   16    8   5.3   2.9   13.0  55.4    -0.3    360  1.8
 10250   -2.7  27.1   240   16    8   4.3   2.4   12.6  54.7    -0.7    343  1.7
 10000   -2.5  27.5   235   16    8   3.9   2.2   12.1  53.9    -1.1    327  1.7
  9750   -2.1  28.2   235   15    8   4.9   2.7   11.7  53.1    -1.5    310  1.6
  9500   -1.8  28.8   225   14    7   4.7   2.6   11.3  52.4    -1.9    292  1.5
  9250   -1.5  29.3   220   13    7   3.8   2.1   10.9  51.6    -2.4    275  1.4
  9000   -1.2  29.8   220   12    6   3.5   1.9   10.4  50.8    -2.8    260  1.3
  8750   -0.9  30.4   215   11    5   4.8   2.6   10.0  50.0    -3.3    243  1.2
  8500   -0.5  31.1   210    9    4   5.5   3.0    9.6  49.4    -3.6    224  1.1
  8250   -0.1  31.8   210    7    4   5.3   2.9    9.3  48.7    -3.9    205  1.0
  8000    0.3  32.5   205    6    3   5.2   2.9    9.0  48.1    -4.3    185  0.9
  7750    0.7  33.3   195    4    2   5.8   3.2    8.6  47.5    -4.6    166  0.8
  7500    1.1  34.0   180    3    1   5.0   2.8    8.3  47.0    -4.9    145  0.7
  7250    1.4  34.5   145    2    1   3.6   2.0    7.9  46.2    -5.4    129  0.7
  7000    1.7  35.1   115    3    2   4.6   2.5    7.4  45.4    -5.8    112  0.6
  6750    2.1  35.8   100    4    2   2.2   1.2    7.0  44.6    -6.2     96  0.5
  6500    2.1  35.8   110    6    3   1.1   0.6    6.3  43.4    -7.0     87  0.4
  6250    2.2  36.0   115    7    4   1.9   1.1    5.7  42.3    -7.6     75  0.4
  6000    2.4  36.3   120    9    4   3.3   1.8    5.2  41.3    -8.2     64  0.3
  5750    2.5  36.5   125    8    4  -4.1  -2.2    4.5  40.2    -8.8     53  0.3
  5500    1.5  34.7   140    6    3 -21.5 -11.8    2.8  37.1   -10.5     75  0.4

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

           11/12/2017 at 0800 MST          |       11/12/2017 at 1100 MST
                                           |
K index... -27.9  LI... +9.2               | K index... -29.6  LI... +9.2
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 -62.9 -81.2  285  68 35   2.4   1.3 | -62.8 -81.0  285  69 36   2.8   1.5
 45000 -59.5 -75.1  290  89 46   1.4   0.7 | -58.9 -74.0  285  87 45   0.3   0.2
 40000 -57.4 -71.3  290  83 43   1.4   0.8 | -58.3 -72.9  290  82 42   0.2   0.1
 38000 -55.4 -67.7  290  81 42   4.3   2.3 | -55.8 -68.4  290  81 42   5.1   2.8
 36000 -52.8 -63.0  290  79 40   4.3   2.3 | -52.7 -62.9  290  81 42   5.1   2.8
 34000 -49.4 -56.9  290  72 37   6.2   3.4 | -49.2 -56.6  290  77 40   7.1   3.9
 32000 -45.7 -50.3  290  60 31   6.2   3.4 | -45.0 -49.0  290  69 36   7.1   3.9
 30000 -41.2 -42.2  290  52 27   8.8   4.8 | -40.5 -40.9  285  61 32   8.1   4.5
 29000 -38.6 -37.5  290  50 26   8.8   4.8 | -37.4 -35.3  285  57 29   8.1   4.5
 28000 -36.0 -32.8  290  49 25   8.8   4.8 | -35.0 -31.0  285  54 28   8.1   4.4
 27000 -33.6 -28.5  290  47 24   6.7   3.7 | -32.7 -26.9  285  51 26   7.6   4.2
 26000 -31.5 -24.7  290  44 23   6.8   3.7 | -30.4 -22.7  290  48 25   7.6   4.2
 25000 -29.5 -21.1  290  42 22   6.8   3.7 | -28.1 -18.6  290  46 24   7.6   4.2
 24000 -27.3 -17.1  290  40 21   9.1   5.0 | -25.9 -14.6  290  43 22   7.1   3.9
 23000 -24.7 -12.5  290  40 20   8.8   4.8 | -23.8 -10.8  290  41 21   7.1   3.9
 22000 -22.0  -7.6  290  39 20   8.8   4.8 | -21.7  -7.1  290  38 20   7.2   3.9
 21000 -19.6  -3.3  290  38 19   7.1   3.9 | -19.4  -2.9  290  36 18   8.2   4.5
 20000 -17.4   0.7  285  35 18   7.2   3.9 | -16.9   1.6  290  34 17   8.2   4.5
 19500 -16.3   2.7  285  33 17   7.2   3.9 | -15.7   3.7  290  33 17   8.2   4.5
 19000 -15.3   4.5  280  32 16   7.2   3.9 | -14.5   5.9  290  32 16   8.1   4.4
 18500 -14.2   6.4  280  30 16   6.7   3.7 | -13.3   8.1  290  31 16   7.5   4.1
 18000 -12.7   9.1  280  28 15   6.8   3.7 | -12.2  10.0  290  30 16   7.7   4.2
 17500 -11.6  11.1  280  27 14   7.3   4.0 | -11.1  12.0  290  30 15   6.4   3.5
 17000 -10.5  13.1  280  26 13   7.4   4.0 | -10.1  13.8  290  29 15   6.1   3.3
 16500  -9.5  14.9  280  25 13   6.2   3.4 |  -9.2  15.4  290  29 15   5.9   3.2
 16000  -8.6  16.5  280  24 12   5.8   3.2 |  -8.4  16.9  290  28 14   5.5   3.0
 15500  -7.7  18.1  280  24 12   5.4   3.0 |  -7.6  18.3  285  27 14   5.5   3.0
 15000  -7.0  19.4  280  23 12   4.8   2.7 |  -6.4  20.5  285  26 13   5.2   2.8
 14500  -6.3  20.7  280  22 12   4.7   2.6 |  -5.6  21.9  285  25 13   5.1   2.8
 14000  -5.7  21.7  280  21 11   3.7   2.0 |  -4.9  23.2  285  24 12   5.0   2.8
 13500  -5.1  22.8  280  20 10   3.8   2.1 |  -4.1  24.6  285  23 12   5.1   2.8
 13000  -4.6  23.7  280  19 10   3.4   1.8 |  -3.4  25.9  280  21 11   5.0   2.7
 12500  -4.1  24.6  280  18  9   3.5   1.9 |  -2.7  27.1  280  20 10   5.0   2.8
 12000  -3.6  25.5  275  16  8   3.9   2.1 |  -1.9  28.6  280  19 10   5.2   2.8
 11500  -3.1  26.4  270  14  7   3.9   2.1 |  -1.2  29.8  280  17  9   5.2   2.8
 11000  -2.5  27.5  265  13  7   4.4   2.4 |  -0.6  30.9  275  15  8   3.9   2.1
 10500  -1.9  28.6  255  13  7   4.5   2.4 |   0.0  32.0  275  13  7   4.0   2.2
 10250  -1.7  28.9  250  13  7   2.6   1.4 |   0.3  32.5  270  13  6   3.2   1.8
 10000  -1.5  29.3  245  13  7   2.5   1.4 |   0.5  32.9  270  12  6   4.0   2.2
  9750  -1.3  29.7  240  12  6   4.9   2.7 |   0.9  33.6  265  11  6   5.6   3.1
  9500  -1.0  30.2  230  13  6   4.5   2.4 |   1.2  34.2  260  10  5   4.6   2.5
  9250  -0.7  30.7  220  12  6   2.7   1.5 |   1.5  34.7  255   9  5   2.9   1.6
  9000  -0.6  30.9  215  12  6   2.2   1.2 |   1.6  34.9  245   8  4   2.5   1.4
  8750  -0.4  31.3  205  12  6   4.1   2.2 |   1.8  35.2  235   8  4   3.3   1.8
  8500  -0.0  32.0  190  12  6   4.8   2.6 |   2.0  35.6  225   8  4   3.7   2.1
  8250   0.3  32.5  180  11  6   4.2   2.3 |   2.3  36.1  215   8  4   4.0   2.2
  8000   0.6  33.1  175  11  6   4.1   2.2 |   2.6  36.7  205   9  4   3.9   2.1
  7750   0.9  33.6  165  11  5   5.2   2.8 |   2.8  37.0  195   9  5   4.0   2.2
  7500   1.4  34.5  160  10  5   6.1   3.4 |   3.1  37.6  185  10  5   5.2   2.9
  7250   1.8  35.2  160  10  5   5.7   3.1 |   3.6  38.5  180   9  5   6.2   3.4
  7000   2.2  36.0  155  10  5   5.9   3.2 |   4.0  39.2  170   8  4   5.5   3.0
  6750   2.6  36.7  150  10  5   4.3   2.3 |   4.4  39.9  160   8  4   6.5   3.6
  6500   2.9  37.2  150  11  6   3.2   1.7 |   5.0  41.0  155   7  4   8.4   4.6
  6250   3.2  37.8  150  11  6   5.3   2.9 |   5.6  42.1  150   6  3   8.6   4.7
  6000   3.5  38.3  150  12  6  -0.1  -0.1 |   6.2  43.2  145   6  3   8.6   4.7
  5750   3.0  37.4  150  10  5 -10.2  -5.6 |   7.0  44.6  140   5  3  12.8   7.0
  5500   2.2  36.0  150   6  3 -11.2  -6.1 |   8.2  46.8  140   5  3  19.4  10.6

           11/12/2017 at 1400 MST          |       11/12/2017 at 1700 MST
                                           |
K index... -14.3  LI... +7.5               | K index... -6.8  LI... +6.7
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 -63.2 -81.8  285  72 37   2.7   1.5 | -63.7 -82.7  285  74 38   2.3   1.2
 45000 -59.4 -74.9  285  89 46   0.3   0.2 | -60.5 -76.9  280  88 45   1.0   0.6
 40000 -58.9 -74.0  285  86 44   0.0   0.0 | -58.9 -74.0  290  95 49   0.6   0.3
 38000 -56.1 -69.0  290  90 46   5.6   3.1 | -55.9 -68.6  285  96 50   5.7   3.1
 36000 -52.7 -62.9  290  96 49   5.6   3.1 | -52.5 -62.5  285  98 51   5.7   3.1
 34000 -48.9 -56.0  285  93 48   7.3   4.0 | -48.7 -55.7  285  91 47   7.0   3.9
 32000 -44.6 -48.3  285  80 41   7.3   4.0 | -44.5 -48.1  280  73 38   7.0   3.9
 30000 -40.1 -40.2  285  68 35   7.8   4.3 | -40.0 -40.0  275  61 31   8.4   4.6
 29000 -37.8 -36.0  285  64 33   7.8   4.3 | -37.5 -35.5  275  59 30   8.4   4.6
 28000 -34.9 -30.8  285  57 30   7.8   4.3 | -34.3 -29.7  280  55 28   8.4   4.6
 27000 -32.5 -26.5  285  54 28   7.8   4.3 | -32.0 -25.6  280  52 27   7.6   4.1
 26000 -30.2 -22.4  285  51 26   7.8   4.3 | -29.7 -21.5  280  47 24   7.5   4.1
 25000 -27.9 -18.2  285  48 24   7.8   4.3 | -27.5 -17.5  280  42 22   7.5   4.1
 24000 -25.6 -14.1  285  45 23   7.4   4.1 | -25.3 -13.5  285  38 20   6.9   3.8
 23000 -23.4 -10.1  290  42 22   7.5   4.1 | -23.2  -9.8  285  35 18   6.9   3.8
 22000 -21.1  -6.0  290  39 20   7.5   4.1 | -21.2  -6.2  285  32 17   6.9   3.8
 21000 -18.9  -2.0  290  37 19   7.4   4.1 | -19.0  -2.2  290  30 16   7.5   4.1
 20000 -16.7   1.9  290  34 18   7.4   4.1 | -16.8   1.8  290  29 15   7.6   4.1
 19500 -15.6   3.9  285  33 17   7.4   4.1 | -15.7   3.7  290  29 15   7.6   4.2
 19000 -14.5   5.9  285  32 16   7.5   4.1 | -14.5   5.9  290  28 15   7.8   4.3
 18500 -13.4   7.9  285  31 16   7.7   4.2 | -13.3   8.1  290  29 15   8.4   4.6
 18000 -12.3   9.9  290  30 16   7.6   4.2 | -12.1  10.2  290  29 15   8.5   4.7
 17500 -11.1  12.0  290  30 15   8.1   4.4 | -10.9  12.4  290  30 15   6.8   3.7
 17000  -9.9  14.2  290  30 15   8.1   4.5 |  -9.9  14.2  290  31 16   6.7   3.7
 16500  -8.6  16.5  295  30 16   7.7   4.2 |  -9.0  15.8  290  31 16   7.0   3.9
 16000  -7.6  18.3  295  30 15   6.8   3.7 |  -7.8  18.0  290  30 15   7.7   4.2
 15500  -6.5  20.3  295  29 15   6.8   3.7 |  -6.6  20.1  290  28 15   7.8   4.3
 15000  -5.0  23.0  295  29 15   6.6   3.6 |  -5.0  23.0  290  28 14   6.7   3.7
 14500  -4.0  24.8  295  29 15   6.2   3.4 |  -3.9  25.0  285  28 15   6.5   3.6
 14000  -3.2  26.2  295  29 15   5.0   2.8 |  -3.0  26.6  285  27 14   5.9   3.2
 13500  -2.4  27.7  290  28 15   5.0   2.7 |  -2.1  28.2  285  27 14   5.9   3.2
 13000  -1.8  28.8  290  27 14   4.3   2.4 |  -1.3  29.7  280  25 13   5.7   3.1
 12500  -1.1  30.0  285  26 13   4.4   2.4 |  -0.5  31.1  280  24 12   5.7   3.1
 12000  -0.5  31.1  285  24 12   4.4   2.4 |   0.3  32.5  275  22 11   5.2   2.9
 11500   0.1  32.2  280  21 11   4.5   2.5 |   1.0  33.8  275  20 10   5.3   2.9
 11000   0.7  33.3  280  17  9   3.9   2.1 |   1.8  35.2  270  17  9   4.9   2.7
 10500   1.2  34.2  275  14  7   4.0   2.2 |   2.4  36.3  265  14  7   4.9   2.7
 10250   1.5  34.7  270  12  6   2.1   1.2 |   2.7  36.9  265  13  7   2.7   1.5
 10000   1.6  34.9  270  11  6   4.3   2.3 |   2.9  37.2  260  13  7   4.1   2.2
  9750   2.1  35.8  260   9  5   7.5   4.1 |   3.3  37.9  260  11  6   6.8   3.7
  9500   2.6  36.7  250   8  4   6.0   3.3 |   3.8  38.8  255  10  5   5.4   3.0
  9250   3.0  37.4  240   7  3   3.8   2.1 |   4.1  39.4  250   9  5   3.3   1.8
  9000   3.2  37.8  230   6  3   3.7   2.1 |   4.3  39.7  245   8  4   2.6   1.4
  8750   3.6  38.5  210   5  3   5.7   3.1 |   4.5  40.1  240   7  3   2.8   1.5
  8500   4.0  39.2  185   5  3   5.8   3.2 |   4.7  40.5  230   5  3   3.7   2.0
  8250   4.4  39.9  180   5  3   5.6   3.1 |   5.0  41.0  220   4  2   5.0   2.7
  8000   4.8  40.6  175   5  3   5.6   3.1 |   5.3  41.5  205   4  2   5.3   2.9
  7750   5.1  41.2  165   5  3   5.6   3.1 |   5.8  42.4  185   3  2   7.1   3.9
  7500   5.5  41.9  160   4  2   7.2   4.0 |   6.3  43.3  170   3  2   8.3   4.6
  7250   6.1  43.0  160   4  2   8.5   4.7 |   6.9  44.4  170   3  2   8.1   4.4
  7000   6.7  44.1  155   3  2   7.9   4.4 |   7.5  45.5  165   3  2   8.2   4.5
  6750   7.3  45.1  155   3  2   8.6   4.7 |   8.1  46.6  165   4  2   8.1   4.5
  6500   8.0  46.4  155   3  1  10.0   5.5 |   8.7  47.7  160   3  2   8.0   4.4
  6250   8.8  47.8  155   3  1  10.1   5.6 |   9.3  48.7  155   2  1   7.9   4.3
  6000   9.5  49.1  155   2  1  10.6   5.8 |   9.9  49.8  140   1  1   8.2   4.5
  5750  10.4  50.7  160   2  1  13.6   7.5 |  10.5  50.9  080   1  0   4.4   2.4
  5500  11.6  52.9  155   2  1  16.9   9.3 |  10.5  50.9  030   1  0  -2.4  -1.3
________________________________________________________________________________

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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