Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 021318
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0618 MST Friday, December 2, 2016

This forecast is for Friday, December 2, 2016:

If the trigger temperature of 31.4 F/-0.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8166 ft MSL (1408 ft AGL)

Forecast maximum temperature................... 26.0 F/-3.8 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Saturday 12/03..... Poor

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 07:00:14 / 16:37:08 MST
Total possible sunshine........... 9 hr 36 min 53 sec (576 min 53 sec)
Altitude of sun at 11:48:48 MST... 29.01 degrees

Upper air data from numerical model forecast valid on 12/02/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 14274 ft MSL (7516 ft AGL)
Lifted condensation level....... 11008 ft MSL (4250 ft AGL)
Lifted index.................... +13.0
K index......................... -9.0

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -59.5 -75.1   245   37   19   2.2   1.2      M     M       M      M    M
 45000  -56.2 -69.2   255   47   24   2.3   1.3      M     M       M      M    M
 40000  -50.6 -59.1   245   59   30   3.8   2.1      M     M       M      M    M
 38000  -48.7 -55.7   240   63   33   1.4   0.8      M     M       M      M    M
 36000  -47.9 -54.2   245   66   34   1.4   0.8      M     M       M      M    M
 34000  -46.9 -52.4   245   69   36   1.5   0.8      M     M       M      M    M
 32000  -46.0 -50.8   245   70   36   1.5   0.8      M     M       M      M    M
 30000  -45.1 -49.2   245   72   37   2.8   1.5      M     M       M      M    M
 29000  -43.8 -46.8   245   67   34   4.5   2.4   24.2  75.6    21.3      M    M
 28000  -42.4 -44.3   245   62   32   4.5   2.5   22.2  71.9    19.9      M    M
 27000  -41.1 -42.0   245   57   29   4.5   2.5   20.2  68.4    18.6      M    M
 26000  -39.5 -39.1   245   53   27   6.1   3.4   18.6  65.5    17.5      M    M
 25000  -37.6 -35.7   245   49   25   6.2   3.4   17.2  62.9    16.6      M    M
 24000  -35.8 -32.4   245   45   23   6.3   3.4   15.9  60.7    15.8      M    M
 23000  -33.7 -28.7   245   41   21   8.1   4.4   15.0  59.0    15.2      M    M
 22000  -31.2 -24.2   250   37   19   8.1   4.5   14.4  57.9    14.8      M    M
 21000  -28.8 -19.8   250   33   17   8.2   4.5   13.9  56.9    14.6      M    M
 20000  -26.4 -15.5   250   30   15   7.9   4.3   13.2  55.7    14.2      M    M
 19500  -25.2 -13.4   250   28   15   7.9   4.3   12.8  55.1    14.0      M    M
 19000  -24.0 -11.2   250   27   14   7.9   4.3   12.5  54.6    13.8      M    M
 18500  -22.8  -9.0   250   25   13   7.9   4.3   12.2  54.0    13.6      M    M
 18000  -21.6  -6.9   250   24   12   8.0   4.4   12.0  53.5    13.5      M    M
 17500  -20.4  -4.7   245   23   12   7.8   4.3   11.7  53.0    13.3      M    M
 17000  -19.2  -2.6   245   21   11   5.5   3.0   11.4  52.5    13.1      M    M
 16500  -18.8  -1.8   240   20   11   1.4   0.8    9.4  48.9    11.4      M    M
 16000  -18.7  -1.7   235   20   10   1.1   0.6    8.0  46.4    10.2      M    M
 15500  -18.6  -1.5   230   18    9   1.1   0.6    6.5  43.7     8.8      M    M
 15000  -18.5  -1.3   225   16    8   3.2   1.7    5.1  41.1     7.5      M    M
 14500  -17.6   0.3   220   15    8   6.7   3.7    4.5  40.1     7.0      M    M
 14000  -16.6   2.1   215   13    7   6.7   3.7    4.0  39.2     6.5      M    M
 13500  -15.6   3.9   215   13    7   6.3   3.5    3.4  38.2     6.1      M    M
 13000  -14.7   5.5   210   12    6   6.3   3.4    2.9  37.2     5.6      M    M
 12500  -13.8   7.2   210   12    6   5.8   3.2    2.3  36.1     5.0      M    M
 12000  -13.0   8.6   205   11    6   4.8   2.6    1.6  34.9     4.4      M    M
 11750  -12.6   9.3   205   10    5   5.1   2.8    1.2  34.2     4.0      M    M
 11500  -12.2  10.0   200    9    5   5.8   3.2    0.9  33.6     3.7      M    M
 11250  -11.8  10.8   200    9    4   5.6   3.1    0.6  33.0     3.4      M    M
 11000  -11.4  11.5   195    8    4   5.9   3.2    0.3  32.5     3.1      M    M
 10750  -10.9  12.4   195    7    4   5.8   3.2   -0.0  31.9     2.8      M    M
 10500  -10.5  13.1   190    7    4   5.4   2.9   -0.4  31.3     2.5      M    M
 10250  -10.1  13.8   190    7    3   5.8   3.2   -0.7  30.7     2.2      M    M
 10000   -9.7  14.5   185    6    3   4.6   2.5   -1.0  30.2     1.9      M    M
  9750   -9.4  15.1   185    6    3   5.0   2.8   -1.4  29.4     1.5      M    M
  9500   -8.9  16.0   180    6    3   6.4   3.5   -1.7  28.9     1.2      M    M
  9250   -8.4  16.9   180    7    3   6.1   3.3   -2.0  28.4     1.0      M    M
  9000   -8.0  17.6   175    7    4   6.8   3.7   -2.3  27.9     0.7      M    M
  8750   -7.4  18.7   175    7    4   6.7   3.7   -2.5  27.6     0.5      M    M
  8500   -6.9  19.6   170    8    4   6.3   3.4   -2.7  27.1     0.3      M    M
  8250   -6.4  20.5   170    8    4   6.3   3.5   -3.0  26.6     0.1      M    M
  8000   -6.0  21.2   165    7    4   5.9   3.2   -3.3  26.1    -0.2     87  0.4
  7750   -5.5  22.1   165    6    3   6.9   3.8   -3.5  25.6    -0.4     66  0.3
  7500   -5.0  23.0   160    4    2   6.0   3.3   -3.7  25.3    -0.6     43  0.2
  7250   -4.7  23.5   160    3    1  -0.5  -0.2   -4.0  24.7    -1.0     28  0.1
  7000   -5.0  23.0   160    1    0  -6.2  -3.4   -4.6  23.8    -1.5     29  0.1
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           12/02/2016 at 0800 MST          |       12/02/2016 at 1100 MST
                                           |
K index... -6.7  LI... +5.9                | K index... +8.5  LI... +4.4
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.1 -74.4  245  33 17   2.1   1.2 | -59.5 -75.1  240  33 17   2.4   1.3
 45000 -55.9 -68.6  245  38 20   2.3   1.3 | -55.8 -68.4  235  38 20   2.6   1.4
 40000 -49.7 -57.5  235  60 31   4.1   2.3 | -49.3 -56.7  240  59 30   4.4   2.4
 38000 -47.9 -54.2  235  66 34   0.4   0.2 | -47.5 -53.5  240  65 34   0.1   0.0
 36000 -47.7 -53.9  235  66 34   0.4   0.2 | -47.5 -53.5  235  66 34   0.0   0.0
 34000 -47.4 -53.3  235  66 34   0.6   0.3 | -47.5 -53.5  235  68 35   0.4   0.2
 32000 -46.8 -52.2  235  64 33   1.0   0.5 | -47.0 -52.6  235  64 33   0.9   0.5
 30000 -46.2 -51.2  235  63 33   2.5   1.4 | -46.4 -51.5  230  60 31   2.2   1.2
 29000 -44.8 -48.6  235  61 31   4.9   2.7 | -45.2 -49.4  230  58 30   4.1   2.2
 28000 -43.4 -46.1  235  58 30   4.9   2.7 | -44.0 -47.2  230  55 28   4.1   2.2
 27000 -41.9 -43.4  230  56 29   4.9   2.7 | -42.8 -45.0  230  52 27   4.2   2.3
 26000 -40.1 -40.2  230  52 27   7.0   3.8 | -41.0 -41.8  225  49 25   7.3   4.0
 25000 -38.0 -36.4  230  46 24   7.0   3.9 | -38.8 -37.8  225  46 24   7.4   4.1
 24000 -35.9 -32.6  230  41 21   7.1   3.9 | -36.6 -33.9  225  42 22   7.4   4.1
 23000 -33.7 -28.7  230  36 18   7.7   4.2 | -34.3 -29.7  225  39 20   8.2   4.5
 22000 -31.4 -24.5  225  32 17   7.7   4.2 | -31.8 -25.2  225  37 19   8.3   4.5
 21000 -29.1 -20.4  225  29 15   7.7   4.2 | -29.3 -20.7  225  34 18   8.4   4.6
 20000 -26.7 -16.1  225  27 14   7.9   4.3 | -27.0 -16.6  225  32 17   7.4   4.1
 19500 -25.5 -13.9  225  26 13   7.9   4.4 | -25.9 -14.6  225  32 16   7.5   4.1
 19000 -24.3 -11.7  225  25 13   8.0   4.4 | -24.8 -12.6  225  31 16   7.5   4.1
 18500 -23.1  -9.6  220  24 12   8.1   4.5 | -23.7 -10.7  225  30 16   7.7   4.2
 18000 -22.0  -7.6  220  24 12   5.8   3.2 | -22.7  -8.9  225  29 15   5.4   3.0
 17500 -21.2  -6.2  220  24 12   5.5   3.0 | -21.9  -7.4  225  28 15   5.3   2.9
 17000 -20.4  -4.7  225  24 12   4.8   2.6 | -21.1  -6.0  220  27 14   5.5   3.0
 16500 -19.8  -3.6  225  24 12   3.6   2.0 | -19.9  -3.8  215  26 14   5.7   3.1
 16000 -19.0  -2.2  225  24 13   4.0   2.2 | -19.0  -2.2  215  26 13   5.9   3.2
 15500 -18.4  -1.1  225  22 12   4.2   2.3 | -18.1  -0.6  210  26 13   5.9   3.2
 15000 -17.8  -0.0  225  21 11   4.5   2.5 | -17.3   0.9  210  25 13   5.8   3.2
 14500 -17.1   1.2  220  19 10   5.1   2.8 | -16.4   2.5  205  24 13   5.7   3.1
 14000 -16.4   2.5  215  17  9   4.8   2.6 | -15.5   4.1  200  23 12   4.9   2.7
 13500 -15.8   3.6  205  16  8   3.4   1.9 | -15.0   5.0  195  21 11   3.1   1.7
 13000 -15.3   4.5  195  16  8   3.5   1.9 | -14.6   5.7  190  19 10   2.9   1.6
 12500 -14.8   5.4  190  16  8   3.6   2.0 | -14.2   6.4  180  18  9   2.0   1.1
 12000 -14.3   6.3  185  16  8   2.6   1.4 | -13.9   7.0  170  18 10  -0.1  -0.1
 11750 -14.0   6.8  180  17  9   4.8   2.6 | -14.0   6.8  165  18 10   1.0   0.6
 11500 -13.5   7.7  175  16  8   6.7   3.7 | -13.7   7.3  160  19 10   4.0   2.2
 11250 -13.1   8.4  175  15  8   6.0   3.3 | -13.5   7.7  155  19 10   2.8   1.6
 11000 -12.6   9.3  170  14  7   6.9   3.8 | -13.3   8.1  155  19 10   4.5   2.5
 10750 -12.1  10.2  165  14  7   7.5   4.1 | -12.8   9.0  155  19 10   5.8   3.2
 10500 -11.5  11.3  165  13  7   7.1   3.9 | -12.4   9.7  150  19 10   5.4   2.9
 10250 -11.0  12.2  160  13  7   7.5   4.1 | -12.0  10.4  150  19 10   5.5   3.0
 10000 -10.5  13.1  155  13  7   6.4   3.5 | -11.6  11.1  145  19 10   5.1   2.8
  9750 -10.0  14.0  150  12  6   6.7   3.7 | -11.3  11.7  145  18  9   5.3   2.9
  9500  -9.4  15.1  150  12  6   8.1   4.4 | -10.8  12.6  145  17  9   5.8   3.2
  9250  -8.8  16.2  145  12  6   7.6   4.2 | -10.4  13.3  145  16  8   5.7   3.1
  9000  -8.3  17.1  145  11  6   7.3   4.0 | -10.0  14.0  145  15  8   5.1   2.8
  8750  -7.8  18.0  140  10  5   7.0   3.8 |  -9.6  14.7  150  14  7   6.6   3.6
  8500  -7.2  19.0  140   9  5   7.5   4.1 |  -9.0  15.8  150  13  7   8.4   4.6
  8250  -6.7  19.9  140   8  4   6.3   3.4 |  -8.4  16.9  145  12  6   9.2   5.1
  8000  -6.3  20.7  135   7  4   4.4   2.4 |  -7.6  18.3  150  12  6  10.2   5.6
  7750  -5.9  21.4  135   6  3   5.9   3.2 |  -6.9  19.6  150  12  6   9.4   5.1
  7500  -5.4  22.3  125   4  2   5.0   2.8 |  -6.2  20.8  150  12  6   9.2   5.1
  7250  -5.2  22.6  105   2  1  -0.8  -0.4 |  -5.5  22.1  150  11  6  10.2   5.6
  7000  -5.5  22.1  065   2  1  -4.4  -2.4 |  -4.7  23.5  150  11  6  10.2   5.6
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/02/2016 at 1400 MST          |       12/02/2016 at 1700 MST
                                           |
K index... +9.2  LI... +3.1                | K index... +10.6  LI... +1.4
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... -1.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.3 -74.7  240  31 16   2.9   1.6 | -59.5 -75.1  240  33 17   3.0   1.6
 45000 -55.0 -67.0  230  40 21   2.8   1.5 | -55.1 -67.2  235  39 20   3.0   1.6
 40000 -49.9 -57.8  240  63 33   3.3   1.8 | -50.2 -58.4  235  60 31   3.1   1.7
 38000 -48.3 -54.9  240  69 36   1.7   0.9 | -48.6 -55.5  235  68 35   1.9   1.0
 36000 -47.3 -53.1  240  71 37   1.7   1.0 | -47.5 -53.5  235  74 38   1.9   1.0
 34000 -46.3 -51.3  235  73 38   1.6   0.9 | -46.4 -51.5  235  80 41   1.6   0.9
 32000 -45.9 -50.6  235  72 37   0.4   0.2 | -46.1 -51.0  235  82 42   0.4   0.2
 30000 -45.7 -50.3  235  71 37   0.6   0.3 | -45.8 -50.4  235  84 43   1.1   0.6
 29000 -44.7 -48.5  230  68 35   3.8   2.1 | -44.3 -47.7  235  82 42   5.8   3.2
 28000 -43.6 -46.5  230  64 33   3.7   2.0 | -42.2 -44.0  235  78 40   5.8   3.2
 27000 -42.2 -44.0  230  59 31   3.7   2.0 | -40.4 -40.7  235  75 39   5.9   3.2
 26000 -40.7 -41.3  230  53 27   6.1   3.3 | -39.1 -38.4  235  66 34   3.8   2.1
 25000 -38.9 -38.0  225  46 24   6.1   3.3 | -37.9 -36.2  230  54 28   3.8   2.1
 24000 -37.1 -34.8  225  38 20   6.1   3.3 | -36.8 -34.2  225  42 22   3.8   2.1
 23000 -34.8 -30.6  225  34 18   8.6   4.7 | -35.0 -31.0  225  35 18   7.9   4.3
 22000 -32.2 -26.0  220  33 17   8.6   4.7 | -32.6 -26.7  220  31 16   8.0   4.4
 21000 -29.7 -21.5  220  31 16   8.7   4.8 | -30.2 -22.4  220  27 14   8.0   4.4
 20000 -27.4 -17.3  220  31 16   7.5   4.1 | -27.8 -18.0  220  27 14   8.2   4.5
 19500 -26.3 -15.3  220  32 16   7.5   4.1 | -26.6 -15.9  220  28 14   8.3   4.5
 19000 -25.1 -13.2  220  32 17   7.5   4.1 | -25.4 -13.7  215  29 15   8.3   4.5
 18500 -24.0 -11.2  220  33 17   7.5   4.1 | -24.1 -11.4  215  29 15   8.3   4.6
 18000 -22.9  -9.2  220  33 17   7.7   4.2 | -23.0  -9.4  220  30 16   7.6   4.2
 17500 -21.8  -7.2  220  33 17   7.7   4.2 | -21.8  -7.2  220  32 16   7.7   4.2
 17000 -20.6  -5.1  220  34 17   7.8   4.3 | -20.7  -5.3  220  33 17   8.3   4.5
 16500 -19.5  -3.1  220  33 17   7.8   4.3 | -19.4  -2.9  220  33 17   8.6   4.7
 16000 -18.3  -0.9  220  33 17   7.6   4.1 | -18.1  -0.6  220  33 17   8.4   4.6
 15500 -17.3   0.9  220  32 17   6.6   3.6 | -17.0   1.4  220  33 17   7.7   4.2
 15000 -16.3   2.7  215  31 16   6.8   3.7 | -15.8   3.6  220  33 17   7.8   4.3
 14500 -15.5   4.1  215  29 15   4.5   2.5 | -14.8   5.4  220  32 16   6.4   3.5
 14000 -14.5   5.9  210  27 14   3.9   2.2 | -13.4   7.9  215  30 16   5.5   3.0
 13500 -14.0   6.8  205  25 13   2.6   1.4 | -12.8   9.0  215  29 15   3.9   2.1
 13000 -13.7   7.3  200  24 12   2.4   1.3 | -12.2  10.0  215  28 14   3.1   1.7
 12500 -13.3   8.1  195  22 12   2.0   1.1 | -12.0  10.4  210  26 13   1.0   0.5
 12000 -13.1   8.4  195  21 11   1.0   0.5 | -11.8  10.8  205  24 12   0.3   0.2
 11750 -13.0   8.6  190  21 11   1.5   0.8 | -11.8  10.8  205  23 12  -0.6  -0.3
 11500 -12.9   8.8  185  21 11   2.4   1.3 | -11.9  10.6  200  22 11  -0.4  -0.2
 11250 -12.7   9.1  185  22 11   1.7   0.9 | -11.9  10.6  195  21 11  -1.1  -0.6
 11000 -12.6   9.3  180  22 11   3.4   1.9 | -12.0  10.4  195  21 11   1.3   0.7
 10750 -12.2  10.0  180  21 11   4.3   2.4 | -11.8  10.8  190  20 10   2.2   1.2
 10500 -12.0  10.4  175  21 11   3.3   1.8 | -11.7  10.9  190  20 10   0.6   0.3
 10250 -11.7  10.9  170  21 11   3.6   2.0 | -11.6  11.1  185  19 10   0.7   0.4
 10000 -11.5  11.3  170  21 11   3.3   1.8 | -11.5  11.3  180  19 10   3.3   1.8
  9750 -11.2  11.8  165  20 10   4.4   2.4 | -11.2  11.8  180  19 10   4.9   2.7
  9500 -10.8  12.6  165  20 10   5.2   2.8 | -10.9  12.4  175  18  9   3.6   2.0
  9250 -10.5  13.1  165  19 10   5.2   2.9 | -10.6  12.9  175  18  9   4.1   2.3
  9000 -10.1  13.8  160  18  9   5.4   3.0 | -10.3  13.5  170  17  9   3.8   2.1
  8750  -9.6  14.7  160  16  8   7.0   3.8 | -10.0  14.0  170  16  8   5.5   3.0
  8500  -9.0  15.8  160  15  8   8.6   4.7 |  -9.5  14.9  165  15  8   7.2   4.0
  8250  -8.4  16.9  155  14  7   9.2   5.0 |  -9.0  15.8  160  14  7   7.9   4.4
  8000  -7.7  18.1  155  13  7  10.1   5.5 |  -8.3  17.1  160  14  7   8.7   4.8
  7750  -7.0  19.4  155  12  6   9.2   5.1 |  -7.7  18.1  160  13  7   8.7   4.8
  7500  -6.3  20.7  155  12  6   8.8   4.8 |  -7.1  19.2  160  12  6   8.0   4.4
  7250  -5.7  21.7  155  11  6   9.5   5.2 |  -6.6  20.1  160  10  5   6.6   3.6
  7000  -4.9  23.2  155  11  6   9.6   5.3 |  -6.1  21.0  160  10  5   6.4   3.5
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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 Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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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