Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 171155
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0455 MST Wednesday, December 17, 2014

This forecast is for Wednesday, December 17, 2014:

If the trigger temperature of 46.1 F/7.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7130 ft MSL (372 ft AGL)

Forecast maximum temperature................... 36.0 F/2.7 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................. 6851 ft MSL (93 ft AGL)
Thermal soaring outlook for Thursday 12/18..... Poor

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

Remarks...

Sunrise/Sunset.................... 07:11:49 / 16:38:41 MST
Total possible sunshine........... 9 hr 26 min 52 sec (566 min 52 sec)
Altitude of sun at 11:55:16 MST... 27.75 degrees

Upper air data from numerical model forecast valid on 12/17/2014 at 0500 MST

Freezing level.................. 6933 ft MSL (175 ft AGL)
Additional freezing level....... 9427 ft MSL (2669 ft AGL)
Convective condensation level... 14817 ft MSL (8059 ft AGL)
Lifted condensation level....... 11301 ft MSL (4543 ft AGL)
Lifted index.................... +7.6
K index......................... +16.2

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  -57.6 -71.7   240   40   20   2.4   1.3      M     M       M      M    M
 45000  -54.1 -65.4   240   54   28   2.5   1.4      M     M       M      M    M
 40000  -52.5 -62.5   240   63   33   0.9   0.5      M     M       M      M    M
 38000  -52.9 -63.2   240   64   33  -3.1  -1.7      M     M       M      M    M
 36000  -54.7 -66.5   235   59   30  -3.1  -1.7      M     M       M      M    M
 34000  -56.5 -69.7   225   54   28   0.6   0.3      M     M       M      M    M
 32000  -52.8 -63.0   225   50   26   6.5   3.6      M     M       M      M    M
 30000  -48.9 -56.0   230   45   23   7.5   4.1   21.1  69.9    14.4      M    M
 29000  -46.5 -51.7   230   43   22   8.0   4.4   20.2  68.4    13.9      M    M
 28000  -44.1 -47.4   235   42   21   8.0   4.4   19.5  67.2    13.5      M    M
 27000  -41.1 -42.0   235   40   21   8.1   4.4   18.8  65.9    13.2      M    M
 26000  -38.5 -37.3   240   38   20   8.8   4.8   18.4  65.0    13.0      M    M
 25000  -35.9 -32.6   240   36   19   8.8   4.8   18.0  64.4    12.8      M    M
 24000  -33.3 -27.9   245   35   18   8.9   4.9   17.7  63.9    12.7      M    M
 23000  -31.0 -23.8   245   33   17   7.5   4.1   17.0  62.5    12.2      M    M
 22000  -28.7 -19.7   245   31   16   7.5   4.1   16.2  61.1    11.7      M    M
 21000  -26.5 -15.7   245   30   15   7.7   4.2   15.5  59.9    11.2      M    M
 20000  -24.2 -11.6   250   28   14   7.9   4.3   14.8  58.6    10.7      M    M
 19500  -23.0  -9.4   250   27   14   7.9   4.3   14.4  58.0    10.5      M    M
 19000  -21.8  -7.2   250   26   14   7.9   4.3   14.1  57.4    10.3      M    M
 18500  -20.6  -5.1   250   26   13   7.8   4.3   13.9  57.0    10.1      M    M
 18000  -19.6  -3.3   250   24   13   7.1   3.9   13.5  56.2     9.8      M    M
 17500  -18.5  -1.3   250   23   12   7.2   3.9   13.0  55.4     9.4      M    M
 17000  -17.5   0.5   250   22   11   7.0   3.9   12.6  54.6     9.1      M    M
 16500  -16.4   2.5   255   21   11   7.0   3.9   12.1  53.8     8.7      M    M
 16000  -15.4   4.3   255   19   10   6.9   3.8   11.7  53.0     8.3      M    M
 15500  -14.4   6.1   260   18    9   6.8   3.7   11.2  52.1     7.9      M    M
 15000  -13.4   7.9   260   16    8   6.8   3.8   10.7  51.2     7.5      M    M
 14500  -12.3   9.9   265   15    8   7.2   4.0   10.3  50.5     7.1      M    M
 14000  -10.7  12.7   275   13    7   7.8   4.3    9.7  49.4     6.6      M    M
 13500   -9.5  14.9   280   13    6   8.1   4.4    9.4  48.9     6.4      M    M
 13000   -8.3  17.1   285   12    6   8.4   4.6    9.1  48.4     6.2      M    M
 12500   -7.0  19.4   285   11    6   8.7   4.8    9.0  48.1     6.0      M    M
 12000   -5.8  21.6   285   11    5   8.3   4.6    8.8  47.8     5.9      M    M
 11750   -5.2  22.6   290   10    5   8.1   4.4    8.7  47.6     5.8      M    M
 11500   -4.6  23.7   290    9    5   7.9   4.3    8.5  47.3     5.6      M    M
 11250   -4.0  24.8   290    9    5   8.7   4.8    8.4  47.1     5.5      M    M
 11000   -3.3  26.1   290    9    4   8.6   4.7    8.3  47.0     5.5      M    M
 10750   -2.7  27.1   290    8    4   7.5   4.1    8.2  46.7     5.3      M    M
 10500   -2.2  28.0   290    7    3   7.4   4.1    8.0  46.4     5.2      M    M
 10250   -1.6  29.1   290    6    3   7.6   4.2    7.8  46.1     5.0      M    M
 10000   -1.1  30.0   295    5    2   6.1   3.4    7.6  45.8     4.9      M    M
  9750   -0.6  30.9   310    4    2   6.5   3.6    7.3  45.2     4.6      M    M
  9500   -0.1  31.8   320    4    2   8.1   4.4    7.2  44.9     4.4      M    M
  9250    0.5  32.9   335    3    2   7.6   4.1    7.0  44.6     4.3      M    M
  9000    1.0  33.8   345    4    2   6.7   3.7    6.8  44.3     4.1      M    M
  8750    1.5  34.7   345    4    2   6.6   3.6    6.6  43.8     3.9      M    M
  8500    2.1  35.8   345    5    2   7.9   4.3    6.4  43.5     3.7      M    M
  8250    2.6  36.7   345    5    3   5.3   2.9    6.2  43.2     3.5      M    M
  8000    2.8  37.0   340    6    3   0.5   0.3    5.7  42.2     3.0      M    M
  7750    2.8  37.0   335    6    3   1.6   0.9    5.0  40.9     2.3      M    M
  7500    3.1  37.6   320    7    4   6.9   3.8    4.5  40.2     1.9      M    M
  7250    3.2  37.8   315    8    4 -12.8  -7.0    4.0  39.1     1.3      M    M
  7000    0.7  33.3   315    7    3 -50.1 -27.5    1.4  34.5    -1.4    102  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           12/17/2014 at 0800 MST          |       12/17/2014 at 1100 MST
                                           |
K index... +19.4  LI... +1.4               | K index... +19.3  LI... +1.2
CAPE... 0.0  CIN... -1.1                   | 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 -56.4 -69.5  240  35 18   2.7   1.5 | -55.8 -68.4  240  39 20   2.7   1.5
 45000 -52.3 -62.1  245  44 22   2.9   1.6 | -51.8 -61.2  235  42 21   2.9   1.6
 40000 -51.7 -61.1  235  54 28   0.2   0.1 | -51.0 -59.8  235  44 22   0.4   0.2
 38000 -51.9 -61.4  230  56 29  -2.4  -1.3 | -51.3 -60.3  230  44 23  -3.4  -1.9
 36000 -53.4 -64.1  230  53 27  -2.5  -1.3 | -53.3 -63.9  225  42 22  -3.5  -1.9
 34000 -55.1 -67.2  225  49 25  -0.0  -0.0 | -55.7 -68.3  220  41 21  -1.6  -0.9
 32000 -53.0 -63.4  220  45 23   3.6   2.0 | -53.8 -64.8  220  34 17   3.5   1.9
 30000 -50.7 -59.3  220  41 21   7.8   4.3 | -51.6 -60.9  215  26 13   7.9   4.3
 29000 -47.9 -54.2  225  38 20   9.3   5.1 | -48.5 -55.3  215  24 13  10.2   5.6
 28000 -45.1 -49.2  225  36 18   9.3   5.1 | -45.4 -49.7  210  23 12  10.3   5.6
 27000 -42.3 -44.1  225  34 17   9.4   5.2 | -42.3 -44.1  210  22 11  10.4   5.7
 26000 -39.7 -39.5  230  31 16   8.6   4.7 | -39.6 -39.3  205  19 10   8.6   4.7
 25000 -37.1 -34.8  230  28 15   8.6   4.7 | -37.0 -34.6  205  17  9   8.6   4.7
 24000 -34.5 -30.1  235  26 13   8.6   4.7 | -34.5 -30.1  195  14  7   8.6   4.7
 23000 -32.0 -25.6  235  24 12   8.3   4.5 | -32.0 -25.6  195  12  6   7.9   4.4
 22000 -29.6 -21.3  240  22 12   8.3   4.5 | -29.6 -21.3  195  10  5   7.9   4.4
 21000 -27.1 -16.8  245  21 11   8.2   4.5 | -27.3 -17.1  195   8  4   8.0   4.4
 20000 -24.8 -12.6  245  18  9   7.4   4.0 | -25.1 -13.2  190   8  4   7.1   3.9
 19500 -23.7 -10.7  245  17  9   7.4   4.1 | -24.0 -11.2  190   7  4   7.1   3.9
 19000 -22.7  -8.9  245  16  8   7.4   4.1 | -23.0  -9.4  185   7  4   7.2   3.9
 18500 -21.6  -6.9  245  14  7   7.5   4.1 | -21.9  -7.4  185   7  4   7.1   3.9
 18000 -20.5  -4.9  245  13  7   6.6   3.6 | -20.8  -5.4  180   7  3   7.4   4.1
 17500 -19.5  -3.1  245  12  6   6.7   3.7 | -19.7  -3.5  175   6  3   7.4   4.1
 17000 -18.5  -1.3  250  11  5   6.6   3.6 | -18.7  -1.7  170   5  3   7.1   3.9
 16500 -17.1   1.2  255   9  5   6.5   3.6 | -17.6   0.3  160   5  2   6.8   3.8
 16000 -16.1   3.0  260   8  4   6.8   3.7 | -16.1   3.0  140   4  2   6.7   3.7
 15500 -15.1   4.8  260   7  4   6.8   3.7 | -15.2   4.6  130   4  2   6.7   3.7
 15000 -14.1   6.6  265   6  3   7.2   4.0 | -14.2   6.4  115   4  2   6.9   3.8
 14500 -13.0   8.6  270   5  3   7.5   4.1 | -13.1   8.4  105   4  2   7.1   3.9
 14000 -11.9  10.6  275   5  2   7.7   4.2 | -12.1  10.2  100   4  2   7.1   3.9
 13500 -10.7  12.7  275   4  2   8.0   4.4 | -11.0  12.2  095   4  2   7.2   3.9
 13000  -9.5  14.9  275   3  2   8.2   4.5 | -10.0  14.0  095   4  2   7.0   3.9
 12500  -8.2  17.2  275   2  1   8.7   4.8 |  -9.0  15.8  100   4  2   6.5   3.6
 12000  -6.9  19.6  265   2  1   8.4   4.6 |  -8.1  17.4  110   4  2   6.3   3.5
 11750  -6.4  20.5  260   2  1   7.8   4.3 |  -7.6  18.3  115   5  2   5.5   3.0
 11500  -5.8  21.6  235   1  1   7.7   4.2 |  -7.2  19.0  120   5  3   5.4   2.9
 11250  -5.2  22.6  205   1  1   7.8   4.3 |  -6.8  19.8  125   6  3   5.2   2.9
 11000  -4.6  23.7  180   1  1   8.3   4.5 |  -6.4  20.5  125   6  3   6.0   3.3
 10750  -4.0  24.8  170   2  1   7.3   4.0 |  -6.0  21.2  130   6  3   6.2   3.4
 10500  -3.5  25.7  145   2  1   6.2   3.4 |  -5.5  22.1  130   6  3   5.7   3.1
 10250  -3.0  26.6  125   2  1   6.5   3.6 |  -5.1  22.8  130   7  3   5.5   3.0
 10000  -2.6  27.3  115   3  2   6.5   3.6 |  -4.7  23.5  130   7  3   7.1   3.9
  9750  -2.1  28.2  095   3  2   6.6   3.6 |  -4.0  24.8  130   6  3   8.3   4.6
  9500  -1.6  29.1  090   4  2   6.5   3.6 |  -3.5  25.7  130   6  3   7.5   4.1
  9250  -1.1  30.0  080   4  2   6.6   3.6 |  -2.9  26.8  130   6  3   7.7   4.2
  9000  -0.6  30.9  075   5  2   5.1   2.8 |  -2.3  27.9  130   5  3   8.1   4.4
  8750  -0.3  31.5  075   4  2   5.5   3.0 |  -1.6  29.1  130   4  2   8.6   4.7
  8500   0.3  32.5  070   4  2   7.5   4.1 |  -1.0  30.2  130   4  2   9.0   4.9
  8250   0.8  33.4  070   4  2   5.4   3.0 |  -0.3  31.5  140   3  1   8.0   4.4
  8000   1.0  33.8  065   3  2   1.1   0.6 |   0.2  32.4  150   2  1   5.0   2.8
  7750   1.1  34.0  065   2  1   2.3   1.3 |   0.5  32.9  170   2  1   5.6   3.0
  7500   1.5  34.7  015   1  0   8.4   4.6 |   1.0  33.8  180   2  1   8.7   4.8
  7250   1.8  35.2  295   2  1  -3.9  -2.1 |   1.6  34.9  190   3  1   6.1   3.4
  7000   0.5  32.9  300   3  2 -29.0 -15.9 |   1.8  35.2  190   2  1   0.3   0.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/17/2014 at 1400 MST          |       12/17/2014 at 1700 MST
                                           |
K index... +20.7  LI... +0.8               | K index... +20.2  LI... +0.8
CAPE... 0.0  CIN... -0.1                   | CAPE... 0.0  CIN... -0.5
                                           |
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 -55.3 -67.5  245  43 22   2.2   1.2 | -55.4 -67.7  245  43 22   2.6   1.4
 45000 -52.0 -61.6  245  47 24   2.2   1.2 | -51.5 -60.7  245  48 25   2.7   1.5
 40000 -50.9 -59.6  230  43 22   0.6   0.3 | -51.1 -60.0  240  47 24   0.0   0.0
 38000 -50.9 -59.6  225  41 21  -3.2  -1.7 | -51.4 -60.5  240  45 23  -3.0  -1.6
 36000 -52.7 -62.9  225  38 19  -3.0  -1.6 | -53.1 -63.6  240  36 19  -2.8  -1.5
 34000 -54.8 -66.6  230  34 17  -2.4  -1.3 | -54.8 -66.6  240  27 14  -2.9  -1.6
 32000 -53.6 -64.5  230  26 13   2.3   1.3 | -54.0 -65.2  230  19 10   2.2   1.2
 30000 -52.3 -62.1  220  18  9   5.8   3.2 | -52.7 -62.9  220  13  7   5.4   2.9
 29000 -49.3 -56.7  220  17  9   9.9   5.4 | -49.7 -57.5  225  11  5  10.0   5.5
 28000 -46.3 -51.3  225  16  8   9.9   5.4 | -46.7 -52.1  240   9  5  10.0   5.5
 27000 -43.4 -46.1  225  15  8   9.9   5.4 | -43.7 -46.7  260   8  4  10.0   5.5
 26000 -40.4 -40.7  225  14  7   9.6   5.3 | -40.9 -41.6  275   7  4   9.2   5.1
 25000 -37.6 -35.7  230  12  6   9.6   5.3 | -38.1 -36.6  290   6  3   9.2   5.0
 24000 -34.7 -30.5  230  11  6   9.6   5.3 | -35.4 -31.7  310   6  3   9.2   5.0
 23000 -32.1 -25.8  230   9  5   7.9   4.3 | -32.8 -27.0  330   6  3   7.8   4.3
 22000 -29.8 -21.6  220   6  3   7.8   4.3 | -30.5 -22.9  355   6  3   7.8   4.3
 21000 -27.4 -17.3  200   3  2   8.0   4.4 | -28.2 -18.8  010   8  4   7.8   4.3
 20000 -25.3 -13.5  170   3  1   7.0   3.9 | -25.9 -14.6  020   8  4   7.7   4.2
 19500 -24.2 -11.6  155   3  1   7.0   3.9 | -24.8 -12.6  020   7  4   7.7   4.2
 19000 -23.2  -9.8  145   3  2   7.1   3.9 | -23.6 -10.5  025   7  4   7.7   4.2
 18500 -22.2  -8.0  140   3  2   7.1   3.9 | -22.5  -8.5  030   7  4   7.7   4.2
 18000 -21.1  -6.0  130   4  2   6.9   3.8 | -21.4  -6.5  030   7  4   7.1   3.9
 17500 -20.1  -4.2  120   4  2   6.9   3.8 | -20.3  -4.5  035   8  4   7.1   3.9
 17000 -19.1  -2.4  110   5  2   7.0   3.8 | -19.3  -2.7  035   8  4   7.2   3.9
 16500 -18.0  -0.4  110   5  2   7.0   3.8 | -18.2  -0.8  035   8  4   7.3   4.0
 16000 -16.5   2.3  105   5  3   7.0   3.9 | -16.6   2.1  035   8  4   7.5   4.1
 15500 -15.5   4.1  105   5  3   7.1   3.9 | -15.5   4.1  035   7  4   7.5   4.1
 15000 -14.4   6.1  105   5  2   7.2   3.9 | -14.4   6.1  035   7  3   7.4   4.1
 14500 -13.3   8.1  105   4  2   7.4   4.0 | -13.3   8.1  035   6  3   7.2   3.9
 14000 -12.3   9.9  105   4  2   7.3   4.0 | -12.2  10.0  040   5  3   7.1   3.9
 13500 -11.2  11.8  110   4  2   6.9   3.8 | -11.3  11.7  045   5  2   6.4   3.5
 13000 -10.2  13.6  115   4  2   6.9   3.8 | -10.3  13.5  050   5  2   6.5   3.5
 12500  -9.2  15.4  115   4  2   7.0   3.8 |  -9.4  15.1  050   5  2   6.6   3.6
 12000  -8.2  17.2  115   5  2   6.0   3.3 |  -8.5  16.7  055   5  2   5.3   2.9
 11750  -7.8  18.0  120   5  3   6.0   3.3 |  -8.1  17.4  055   5  2   5.2   2.9
 11500  -7.4  18.7  115   5  3   6.2   3.4 |  -7.8  18.0  060   5  2   5.3   2.9
 11250  -6.9  19.6  115   5  3   6.0   3.3 |  -7.4  18.7  060   5  2   5.2   2.8
 11000  -6.5  20.3  115   5  3   6.7   3.7 |  -7.0  19.4  065   5  2   5.6   3.1
 10750  -6.0  21.2  115   5  3   6.3   3.4 |  -6.6  20.1  065   5  2   5.4   3.0
 10500  -5.6  21.9  110   5  3   5.1   2.8 |  -6.2  20.8  065   5  3   4.8   2.6
 10250  -5.2  22.6  105   5  3   5.9   3.2 |  -5.9  21.4  065   6  3   5.0   2.8
 10000  -4.8  23.4  105   5  3   3.9   2.1 |  -5.5  22.1  065   6  3   4.6   2.5
  9750  -4.6  23.7  090   5  2   2.6   1.4 |  -5.2  22.6  060   7  3   4.6   2.5
  9500  -4.3  24.3  080   4  2   3.7   2.0 |  -4.8  23.4  060   6  3   4.8   2.6
  9250  -4.1  24.6  070   4  2   3.2   1.8 |  -4.5  23.9  055   6  3   5.0   2.7
  9000  -3.8  25.2  055   4  2   4.0   2.2 |  -4.1  24.6  050   6  3   3.9   2.2
  8750  -3.5  25.7  055   4  2   5.9   3.2 |  -3.9  25.0  050   5  3   3.8   2.1
  8500  -3.0  26.6  060   4  2   6.4   3.5 |  -3.5  25.7  045   4  2   4.7   2.6
  8250  -2.5  27.5  060   4  2   6.6   3.6 |  -3.2  26.2  030   3  1   4.8   2.6
  8000  -2.0  28.4  065   4  2   9.3   5.1 |  -2.8  27.0  025   2  1   6.6   3.6
  7750  -1.2  29.8  065   4  2   9.8   5.4 |  -2.3  27.9  045   2  1   7.4   4.1
  7500  -0.6  30.9  065   4  2   8.3   4.5 |  -1.8  28.8  065   2  1   7.8   4.3
  7250   0.0  32.0  065   4  2   8.0   4.4 |  -1.2  29.8  075   2  1   5.8   3.2
  7000   0.6  33.1  065   4  2   6.8   3.7 |  -1.0  30.2  080   2  1   0.4   0.2
  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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