Soaring Guidance
Issued by NWS Denver/Boulder, CO

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720
UXUS97 KBOU 140106
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1806 MST Monday, November 13, 2017

This forecast is for Tuesday, November 14, 2017:

If the trigger temperature of 67.1 F/19.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 339 ft/min (1.7 m/s)
   Maximum height of thermals.................. 9929 ft MSL (4622 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1315 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................. 7392 ft MSL (2086 ft AGL)
Thermal soaring outlook for Wednesday 11/15.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 45823 ft MSL (40516 ft AGL)
Wave soaring outlook for Wednesday 11/15....... Poor

Remarks...

Sunrise/Sunset.................... 06:43:25 / 16:44:24 MST
Total possible sunshine........... 10 hr 0 min 59 sec (600 min 59 sec)
Altitude of sun at 11:44:07 MST... 31.86 degrees

Upper air data from numerical model forecast valid on 11/14/2017 at 0500 MST

Freezing level.................. 13203 ft MSL (7896 ft AGL)
Convective condensation level... 21649 ft MSL (16342 ft AGL)
Lifted condensation level....... 17722 ft MSL (12415 ft AGL)
Lifted index.................... +6.9
K index......................... -6.9

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  -66.2 -87.2   285   93   48   1.4   0.8      M     M       M      M    M
 45000  -64.0 -83.2   280  105   54   2.3   1.3      M     M       M      M    M
 40000  -60.5 -76.9   280   92   47   1.9   1.0      M     M       M      M    M
 38000  -56.8 -70.2   280   83   43   6.9   3.8      M     M       M      M    M
 36000  -52.7 -62.9   280   74   38   6.9   3.8      M     M       M      M    M
 34000  -48.3 -54.9   280   69   36   8.1   4.4      M     M       M      M    M
 32000  -43.5 -46.3   280   69   35   8.1   4.4      M     M       M      M    M
 30000  -38.8 -37.8   280   67   34   7.4   4.1   37.3  99.2    13.1      M    M
 29000  -36.0 -32.8   280   64   33   7.4   4.1   36.2  97.1    12.4      M    M
 28000  -33.8 -28.8   280   62   32   7.4   4.1   35.4  95.7    11.9      M    M
 27000  -31.5 -24.7   280   60   31   7.8   4.3   34.6  94.2    11.4      M    M
 26000  -29.2 -20.6   280   58   30   7.8   4.3   33.8  92.8    10.9      M    M
 25000  -26.9 -16.4   280   56   29   7.8   4.3   33.1  91.6    10.4      M    M
 24000  -24.5 -12.1   275   54   28   8.3   4.5   32.5  90.4    10.0      M    M
 23000  -22.1  -7.8   275   52   27   8.2   4.5   31.8  89.3     9.7      M    M
 22000  -19.6  -3.3   275   51   26   8.2   4.5   31.3  88.4     9.3      M    M
 21000  -17.2   1.0   275   48   25   7.8   4.3   30.7  87.3     8.9      M    M
 20000  -14.9   5.2   275   46   24   7.8   4.3   30.0  86.0     8.4      M    M
 19500  -13.7   7.3   275   45   23   7.8   4.3   29.7  85.5     8.2      M    M
 19000  -12.5   9.5   275   43   22   7.7   4.2   29.4  84.9     8.0      M    M
 18500  -11.4  11.5   270   42   21   6.8   3.8   29.0  84.2     7.7      M    M
 18000  -10.4  13.3   270   40   20   6.9   3.8   28.5  83.3     7.3      M    M
 17500   -9.4  15.1   270   38   19   6.9   3.8   28.0  82.4     6.9      M    M
 17000   -8.4  16.9   270   35   18   6.8   3.7   27.5  81.5     6.5      M    M
 16500   -7.4  18.7   270   33   17   6.8   3.7   27.0  80.6     6.1      M    M
 16000   -6.4  20.5   270   30   16   6.5   3.6   26.5  79.7     5.6      M    M
 15500   -5.4  22.3   270   28   14   6.4   3.5   25.9  78.7     5.2      M    M
 15000   -3.8  25.2   270   24   13   7.4   4.1   25.3  77.5     4.6      M    M
 14500   -2.7  27.1   270   22   12   7.4   4.1   24.9  76.8     4.3      M    M
 14000   -1.6  29.1   270   21   11   7.5   4.1   24.5  76.1     4.0      M    M
 13500   -0.5  31.1   275   21   11   7.5   4.1   24.2  75.5     3.6      M    M
 13000    0.6  33.1   275   20   10   7.2   4.0   23.8  74.8     3.3      M    M
 12500    1.7  35.1   280   21   11   7.4   4.1   23.4  74.0     2.9      M    M
 12000    2.7  36.9   280   20   10   5.8   3.2   22.9  73.2     2.5      M    M
 11500    3.6  38.5   280   18    9   5.9   3.2   22.2  72.0     1.9      M    M
 11000    4.4  39.9   280   17    9   6.1   3.4   21.6  71.0     1.3      M    M
 10500    5.3  41.5   280   16    8   6.6   3.6   21.1  69.9     0.8      M    M
 10250    5.8  42.4   280   16    8   4.3   2.3   20.8  69.4     0.5      M    M
 10000    6.1  43.0   280   16    8   5.1   2.8   20.3  68.5     0.0      M    M
  9750    6.6  43.9   280   16    8   7.8   4.3   20.1  68.2    -0.2    319  1.6
  9500    7.1  44.8   275   15    8   7.4   4.1   19.9  67.8    -0.4    296  1.5
  9250    7.7  45.9   275   14    7   6.3   3.4   19.7  67.5    -0.5    272  1.4
  9000    8.1  46.6   275   14    7   5.4   3.0   19.4  66.9    -0.9    253  1.3
  8750    8.5  47.3   275   15    8   6.2   3.4   19.1  66.3    -1.2    233  1.2
  8500    8.9  48.0   275   16    8   6.0   3.3   18.8  65.8    -1.5    212  1.1
  8250    9.4  48.9   275   16    8   5.7   3.1   18.5  65.3    -1.8    192  1.0
  8000    9.8  49.6   275   15    8   5.3   2.9   18.2  64.7    -2.1    172  0.9
  7750   10.1  50.2   270   14    7   5.0   2.8   17.8  64.1    -2.5    154  0.8
  7500   10.5  50.9   270   13    7   5.2   2.9   17.5  63.4    -2.8    135  0.7
  7250   10.9  51.6   270   12    6   6.1   3.4   17.1  62.9    -3.2    116  0.6
  7000   11.4  52.5   265   10    5   5.9   3.2   16.9  62.4    -3.4     95  0.5
  6750   11.8  53.2   255    8    4   7.7   4.2   16.6  61.9    -3.7     74  0.4
  6500   12.2  54.0   250    7    3  -0.9  -0.5   16.3  61.3    -4.0     54  0.3
  6250   11.7  53.1   235    7    3 -10.2  -5.6   15.0  58.9    -5.4     64  0.3
  6000   11.1  52.0   225    7    3  -4.7  -2.6   13.6  56.6    -6.7     74  0.4
  5750   10.6  51.1   220    7    4 -14.3  -7.9   12.4  54.4    -8.0     82  0.4
  5500    8.1  46.6   215    8    4 -53.3 -29.3    9.3  48.8   -11.1    148  0.8

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

           11/14/2017 at 0800 MST          |       11/14/2017 at 1100 MST
                                           |
K index... -9.4  LI... +6.7                | K index... -6.9  LI... +6.6
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 -65.7 -86.3  280  91 47   0.7   0.4 | -66.1 -87.0  275  96 50   0.9   0.5
 45000 -64.6 -84.3  280 108 56   1.7   0.9 | -64.6 -84.3  280 107 55   2.3   1.3
 40000 -62.2 -80.0  275  91 47   1.8   1.0 | -61.3 -78.3  275  94 49   2.3   1.3
 38000 -58.4 -73.1  275  86 44   7.9   4.3 | -58.1 -72.6  270  86 44   6.6   3.6
 36000 -53.1 -63.6  275  81 42   7.9   4.3 | -54.1 -65.4  270  76 39   6.6   3.6
 34000 -48.3 -54.9  275  76 39   7.9   4.3 | -49.1 -56.4  270  69 35   8.4   4.6
 32000 -43.6 -46.5  275  71 37   7.9   4.3 | -44.1 -47.4  270  65 33   8.4   4.6
 30000 -39.0 -38.2  275  66 34   7.4   4.1 | -39.1 -38.4  270  62 32   8.3   4.5
 29000 -36.7 -34.1  270  63 32   7.4   4.1 | -36.6 -33.9  270  62 32   8.3   4.5
 28000 -34.5 -30.1  270  60 31   7.5   4.1 | -34.2 -29.6  270  61 31   8.3   4.5
 27000 -32.2 -26.0  270  58 30   8.2   4.5 | -31.7 -25.1  270  60 31   8.1   4.4
 26000 -29.7 -21.5  270  57 29   8.2   4.5 | -29.3 -20.7  265  58 30   8.1   4.4
 25000 -27.2 -17.0  270  55 28   8.2   4.5 | -26.9 -16.4  265  57 29   8.1   4.4
 24000 -24.8 -12.6  270  54 28   8.1   4.5 | -24.5 -12.1  265  55 29   7.8   4.3
 23000 -22.4  -8.3  270  52 27   8.1   4.5 | -22.1  -7.8  265  54 28   7.8   4.3
 22000 -19.9  -3.8  270  51 26   8.1   4.5 | -19.8  -3.6  260  53 27   7.8   4.3
 21000 -17.5   0.5  270  49 25   8.2   4.5 | -17.4   0.7  260  52 27   7.6   4.2
 20000 -15.0   5.0  270  48 25   8.2   4.5 | -15.2   4.6  265  50 26   7.7   4.2
 19500 -13.8   7.2  270  47 24   8.2   4.5 | -14.0   6.8  265  50 26   7.7   4.2
 19000 -12.6   9.3  270  46 24   8.2   4.5 | -12.9   8.8  265  49 25   7.7   4.2
 18500 -10.8  12.6  270  44 23   7.5   4.1 | -11.8  10.8  265  48 25   7.4   4.1
 18000  -9.7  14.5  270  43 22   7.5   4.1 | -10.1  13.8  265  47 24   7.5   4.1
 17500  -8.6  16.5  270  42 22   7.4   4.1 |  -9.0  15.8  265  46 24   7.3   4.0
 17000  -7.5  18.5  270  40 21   7.4   4.1 |  -7.9  17.8  265  45 23   7.3   4.0
 16500  -6.4  20.5  270  39 20   6.9   3.8 |  -6.8  19.8  265  43 22   7.0   3.8
 16000  -5.4  22.3  270  37 19   6.7   3.7 |  -5.8  21.6  265  42 22   6.8   3.7
 15500  -4.4  24.1  270  36 18   6.6   3.6 |  -4.8  23.4  270  40 21   6.7   3.7
 15000  -3.4  25.9  270  34 17   6.3   3.4 |  -3.8  25.2  270  39 20   6.5   3.6
 14500  -2.5  27.5  270  32 16   6.3   3.4 |  -2.8  27.0  270  37 19   6.6   3.6
 14000  -1.6  29.1  270  30 15   6.2   3.4 |  -1.8  28.8  270  35 18   6.1   3.4
 13500  -0.6  30.9  270  28 14   6.2   3.4 |  -0.9  30.4  270  34 17   6.2   3.4
 13000   0.3  32.5  270  26 13   6.0   3.3 |   0.0  32.0  275  32 16   5.8   3.2
 12500   1.1  34.0  270  23 12   5.9   3.3 |   0.9  33.6  275  30 15   5.8   3.2
 12000   2.0  35.6  270  21 11   6.3   3.4 |   1.7  35.1  275  28 15   6.0   3.3
 11500   3.0  37.4  270  20 10   6.3   3.5 |   2.6  36.7  275  26 14   6.0   3.3
 11000   3.9  39.0  275  18  9   6.3   3.4 |   3.6  38.5  275  25 13   6.5   3.6
 10500   4.8  40.6  275  17  9   6.9   3.8 |   4.5  40.1  275  22 11   7.2   4.0
 10250   5.3  41.5  275  16  8   3.8   2.1 |   5.0  41.0  275  21 11   4.0   2.2
 10000   5.5  41.9  275  15  8   4.6   2.5 |   5.2  41.4  275  20 10   4.5   2.4
  9750   6.0  42.8  275  14  7   8.0   4.4 |   5.7  42.3  275  19 10   8.0   4.4
  9500   6.6  43.9  275  13  7   7.6   4.2 |   6.2  43.2  275  17  9   7.3   4.0
  9250   7.1  44.8  275  12  6   5.7   3.1 |   6.8  44.2  275  16  8   6.6   3.6
  9000   7.4  45.3  275  12  6   4.7   2.6 |   7.2  45.0  270  15  8   6.2   3.4
  8750   7.9  46.2  275  13  7   6.7   3.7 |   7.7  45.9  270  13  7   7.0   3.8
  8500   8.4  47.1  275  14  7   6.7   3.7 |   8.2  46.8  270  12  6   7.0   3.8
  8250   8.8  47.8  275  14  7   5.4   3.0 |   8.7  47.7  275  11  6   6.6   3.6
  8000   9.2  48.6  275  13  6   4.5   2.4 |   9.2  48.6  265   9  5   6.3   3.4
  7750   9.5  49.1  270  11  6   5.0   2.7 |   9.7  49.5  255   7  4   6.2   3.4
  7500   9.9  49.8  270   9  5   5.6   3.1 |  10.1  50.2  245   6  3   6.5   3.5
  7250  10.4  50.7  260   7  4   7.3   4.0 |  10.7  51.3  230   5  3   7.6   4.2
  7000  11.0  51.8  250   6  3   7.2   3.9 |  11.3  52.3  210   5  3   8.1   4.4
  6750  11.5  52.7  235   5  3   9.9   5.4 |  11.9  53.4  190   5  3   7.7   4.2
  6500  12.1  53.8  215   5  2   0.8   0.4 |  12.4  54.3  180   6  3   7.2   3.9
  6250  11.6  52.9  210   6  3  -9.3  -5.1 |  13.0  55.4  180   6  3   6.8   3.7
  6000  11.1  52.0  205   6  3  -4.8  -2.6 |  13.5  56.3  180   5  3   6.9   3.8
  5750  10.6  51.1  205   7  4 -11.2  -6.2 |  13.9  57.0  180   5  3   5.1   2.8
  5500   8.8  47.8  210   8  4 -39.8 -21.8 |  14.2  57.6  185   4  2   5.2   2.9

           11/14/2017 at 1400 MST          |       11/14/2017 at 1700 MST
                                           |
K index... -5.6  LI... +7.3                | K index... +5.4  LI... +6.4
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 -65.8 -86.4  275  97 50   0.9   0.5 | -65.5 -85.9  275  95 49   1.7   0.9
 45000 -64.3 -83.7  275 108 55   2.9   1.6 | -62.9 -81.2  275 106 54   2.7   1.5
 40000 -60.2 -76.4  270 100 52   2.8   1.5 | -58.9 -74.0  280  99 51   2.7   1.5
 38000 -57.5 -71.5  270  90 46   5.3   2.9 | -56.7 -70.1  280  92 47   4.2   2.3
 36000 -54.3 -65.7  265  77 40   5.3   2.9 | -54.2 -65.6  275  82 42   4.2   2.3
 34000 -49.5 -57.1  260  65 34   9.3   5.1 | -50.0 -58.0  270  72 37   9.4   5.1
 32000 -43.9 -47.0  255  58 30   9.3   5.1 | -44.4 -47.9  260  64 33   9.3   5.1
 30000 -38.7 -37.7  255  55 28   8.1   4.5 | -39.1 -38.4  255  58 30   8.2   4.5
 29000 -36.2 -33.2  260  56 29   8.1   4.5 | -36.7 -34.1  260  56 29   8.2   4.5
 28000 -33.8 -28.8  265  58 30   8.1   4.5 | -34.2 -29.6  265  53 28   8.2   4.5
 27000 -31.3 -24.3  270  59 30   8.4   4.6 | -31.8 -25.2  270  53 27   7.7   4.2
 26000 -28.8 -19.8  270  59 30   8.4   4.6 | -29.5 -21.1  270  57 29   7.7   4.2
 25000 -26.3 -15.3  270  59 30   8.4   4.6 | -27.2 -17.0  275  61 31   7.7   4.2
 24000 -23.8 -10.8  275  59 30   7.4   4.1 | -24.8 -12.6  280  64 33   7.7   4.2
 23000 -21.6  -6.9  275  59 30   7.4   4.1 | -22.5  -8.5  280  62 32   7.7   4.2
 22000 -19.4  -2.9  275  58 30   7.5   4.1 | -20.2  -4.4  280  61 31   7.7   4.2
 21000 -17.2   1.0  275  57 29   7.1   3.9 | -18.0  -0.4  280  59 31   5.6   3.1
 20000 -15.1   4.8  275  55 29   7.2   3.9 | -16.3   2.7  280  57 29   5.8   3.2
 19500 -14.0   6.8  270  55 28   7.2   3.9 | -15.4   4.3  280  55 28   5.8   3.2
 19000 -12.9   8.8  270  54 28   7.2   3.9 | -14.5   5.9  280  54 28   5.9   3.2
 18500 -11.8  10.8  270  53 27   6.9   3.8 | -13.7   7.3  280  52 27   5.3   2.9
 18000 -10.8  12.6  270  52 27   6.9   3.8 | -12.9   8.8  275  51 26   5.3   2.9
 17500  -9.3  15.3  275  50 26   6.4   3.5 | -11.8  10.8  275  49 25   5.2   2.9
 17000  -8.3  17.1  275  49 25   6.4   3.5 | -11.0  12.2  275  47 24   5.3   2.9
 16500  -7.4  18.7  275  48 25   6.1   3.4 | -10.3  13.5  275  46 23   5.3   2.9
 16000  -6.5  20.3  275  46 24   5.8   3.2 |  -9.5  14.9  275  44 22   5.2   2.9
 15500  -5.6  21.9  275  44 23   5.8   3.2 |  -8.8  16.2  275  42 21   5.3   2.9
 15000  -4.8  23.4  275  42 22   5.4   3.0 |  -7.9  17.8  275  40 21   5.9   3.2
 14500  -4.0  24.8  275  40 21   5.5   3.0 |  -7.1  19.2  280  38 20   5.7   3.1
 14000  -3.2  26.2  275  38 20   5.5   3.0 |  -6.2  20.8  280  36 19   6.6   3.6
 13500  -2.4  27.7  275  36 18   5.5   3.0 |  -5.2  22.6  280  34 18   6.6   3.6
 13000  -1.6  29.1  275  34 17   6.0   3.3 |  -4.2  24.4  280  32 17   7.3   4.0
 12500  -0.6  30.9  275  31 16   6.1   3.4 |  -3.1  26.4  280  31 16   7.3   4.0
 12000   0.3  32.5  275  29 15   7.0   3.8 |  -1.9  28.6  285  29 15   8.1   4.5
 11500   1.4  34.5  275  27 14   7.3   4.0 |  -0.7  30.7  285  27 14   8.3   4.6
 11000   2.4  36.3  275  25 13   6.4   3.5 |   0.6  33.1  285  25 13   8.4   4.6
 10500   3.3  37.9  275  22 11   5.4   3.0 |   1.8  35.2  285  23 12   9.0   4.9
 10250   3.7  38.7  275  20 10   8.6   4.7 |   2.4  36.3  285  22 11   5.8   3.2
 10000   4.5  40.1  275  19 10   9.9   5.4 |   2.8  37.0  285  21 11   7.1   3.9
  9750   5.1  41.2  270  16  8   7.6   4.2 |   3.6  38.5  285  19 10  11.1   6.1
  9500   5.7  42.3  270  14  7   8.5   4.7 |   4.3  39.7  285  18  9  10.5   5.8
  9250   6.3  43.3  265  11  6   7.2   4.0 |   5.1  41.2  285  16  8   8.9   4.9
  9000   6.8  44.2  260   9  5   7.4   4.1 |   5.7  42.3  290  15  8   8.4   4.6
  8750   7.5  45.5  260   7  4   8.7   4.8 |   6.4  43.5  290  14  7  10.1   5.6
  8500   8.1  46.6  255   6  3   8.2   4.5 |   7.2  45.0  295  13  7  10.0   5.5
  8250   8.7  47.7  250   5  2   9.1   5.0 |   7.9  46.2  295  13  7   9.6   5.3
  8000   9.4  48.9  245   3  2   9.7   5.3 |   8.6  47.5  300  12  6   9.2   5.1
  7750  10.1  50.2  240   3  1   8.9   4.9 |   9.3  48.7  300  11  6   9.2   5.1
  7500  10.8  51.4  240   2  1   8.7   4.8 |  10.0  50.0  305  11  6   9.2   5.1
  7250  11.5  52.7  240   2  1   9.6   5.3 |  10.7  51.3  310  11  5   9.5   5.2
  7000  12.2  54.0  240   2  1  10.2   5.6 |  11.4  52.5  315  10  5   9.6   5.2
  6750  13.0  55.4  245   2  1   9.0   5.0 |  12.1  53.8  320  10  5   8.3   4.5
  6500  13.6  56.5  245   2  1   9.2   5.1 |  12.6  54.7  325  10  5   8.1   4.5
  6250  14.4  57.9  250   2  1  10.5   5.8 |  13.3  55.9  330  10  5   8.8   4.8
  6000  15.2  59.4  255   2  1  10.7   5.9 |  14.0  57.2  330  10  5   9.2   5.1
  5750  16.0  60.8  255   2  1   9.9   5.4 |  14.6  58.3  335  10  5   7.5   4.1
  5500  16.7  62.1  260   2  1  10.8   5.9 |  14.9  58.8  340   9  5  -0.2  -0.1
________________________________________________________________________________

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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