Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 251424
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0723 MST Thursday, December 25, 2014

This forecast is for Thursday, December 25, 2014:

If the trigger temperature of 50.3 F/10.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8487 ft MSL (1315 ft AGL)

Forecast maximum temperature................... 44.0 F/7.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7761 ft MSL (589 ft AGL)
Thermal soaring outlook for Friday 12/26....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:15:50 / 16:42:37 MST
Total possible sunshine........... 9 hr 26 min 47 sec (566 min 47 sec)
Altitude of sun at 11:59:13 MST... 27.74 degrees

Upper air data from numerical model forecast valid on 12/25/2014 at 0500 MST

Freezing level.................. 7302 ft MSL (130 ft AGL)
Additional freezing level....... 10380 ft MSL (3208 ft AGL)
Convective condensation level... 17133 ft MSL (9961 ft AGL)
Lifted condensation level....... 14276 ft MSL (7104 ft AGL)
Lifted index.................... +5.8
K index......................... +11.9

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  -55.5 -67.9   240   39   20   1.9   1.0      M     M       M      M    M
 45000  -52.7 -62.9   250   52   27   1.8   1.0      M     M       M      M    M
 40000  -55.9 -68.6   240   61   31  -2.5  -1.4      M     M       M      M    M
 38000  -56.4 -69.5   235   64   33   3.4   1.9      M     M       M      M    M
 36000  -54.3 -65.7   240   65   34   3.6   2.0      M     M       M      M    M
 34000  -52.1 -61.8   240   67   34   3.5   1.9      M     M       M      M    M
 32000  -49.4 -56.9   240   63   32   4.7   2.6      M     M       M      M    M
 30000  -46.5 -51.7   240   58   30   4.6   2.5      M     M       M      M    M
 29000  -44.4 -47.9   240   55   28   7.7   4.2   22.4  72.3    12.2      M    M
 28000  -42.1 -43.8   240   52   27   7.6   4.2   21.5  70.7    11.6      M    M
 27000  -39.8 -39.6   235   49   25   7.6   4.2   20.8  69.4    11.2      M    M
 26000  -37.0 -34.6   235   47   24   7.4   4.1   19.8  67.6    10.6      M    M
 25000  -34.8 -30.6   240   47   24   7.5   4.1   18.9  65.9     9.9      M    M
 24000  -32.6 -26.7   240   47   24   7.5   4.1   18.1  64.5     9.4      M    M
 23000  -30.2 -22.4   245   46   24   8.3   4.5   17.4  63.3     8.9      M    M
 22000  -27.8 -18.0   245   45   23   8.3   4.5   16.8  62.3     8.5      M    M
 21000  -25.3 -13.5   250   44   23   8.3   4.6   16.4  61.5     8.2      M    M
 20000  -22.8  -9.0   250   42   22   8.2   4.5   15.8  60.5     7.8      M    M
 19500  -21.6  -6.9   250   41   21   8.2   4.5   15.5  59.9     7.6      M    M
 19000  -20.4  -4.7   250   40   21   8.2   4.5   15.3  59.5     7.4      M    M
 18500  -19.2  -2.6   255   39   20   8.2   4.5   15.0  59.0     7.2      M    M
 18000  -18.0  -0.4   255   38   20   8.3   4.6   14.8  58.6     7.1      M    M
 17500  -16.7   1.9   255   37   19   8.4   4.6   14.5  58.2     6.9      M    M
 17000  -15.5   4.1   255   36   19   8.4   4.6   14.3  57.8     6.7      M    M
 16500  -14.3   6.3   255   36   18   8.2   4.5   14.1  57.3     6.5      M    M
 16000  -13.1   8.4   260   35   18   8.1   4.4   13.8  56.8     6.2      M    M
 15500  -11.8  10.8   260   34   17   9.2   5.1   13.6  56.5     6.1      M    M
 15000  -10.4  13.3   255   31   16   9.3   5.1   13.5  56.4     6.0      M    M
 14500   -9.1  15.6   250   28   15   8.4   4.6   13.5  56.3     6.0      M    M
 14000   -7.9  17.8   250   25   13   7.6   4.2   13.1  55.6     5.7      M    M
 13500   -6.8  19.8   245   22   11   7.3   4.0   12.8  55.0     5.4      M    M
 13000   -5.8  21.6   240   21   11   6.5   3.6   12.3  54.1     4.9      M    M
 12500   -4.8  23.4   240   21   11   5.7   3.1   11.8  53.2     4.5      M    M
 12000   -4.0  24.8   240   20   10   7.5   4.1   11.2  52.1     3.9      M    M
 11750   -3.4  25.9   245   20   10   7.9   4.3   11.0  51.8     3.8      M    M
 11500   -2.8  27.0   245   20   10   7.8   4.3   10.9  51.6     3.7      M    M
 11250   -2.2  28.0   245   20   10   7.1   3.9   10.7  51.3     3.5      M    M
 11000   -1.7  28.9   250   20   10   7.2   4.0   10.5  50.9     3.3      M    M
 10750   -1.1  30.0   255   20   10   8.0   4.4   10.3  50.6     3.1      M    M
 10500   -0.5  31.1   255   21   11   7.8   4.3   10.2  50.3     3.0      M    M
 10250    0.0  32.0   260   21   11   6.8   3.7   10.0  50.0     2.8      M    M
 10000    0.9  33.6   260   22   11   6.0   3.3    9.5  49.0     2.3      M    M
  9750    1.4  34.5   265   24   12   5.5   3.0    9.1  48.4     2.0      M    M
  9500    1.8  35.2   265   26   13   5.4   3.0    8.8  47.9     1.7      M    M
  9250    2.2  36.0   265   28   14   5.5   3.0    8.5  47.2     1.4      M    M
  9000    2.6  36.7   265   30   16   4.8   2.6    8.1  46.7     1.0      M    M
  8750    2.8  37.0   265   32   17   0.7   0.4    7.6  45.7     0.6      M    M
  8500    2.7  36.9   265   32   16  -2.9  -1.6    6.8  44.2    -0.3    116  0.6
  8250    2.5  36.5   265   30   15  -2.9  -1.6    5.8  42.4    -1.3    116  0.6
  8000    2.2  36.0   265   27   14  -4.2  -2.3    4.8  40.7    -2.2    115  0.6
  7750    1.7  35.1   265   24   13 -11.2  -6.1    3.6  38.4    -3.5    125  0.6
  7500    0.5  32.9   265   16    8 -18.1  -9.9    1.7  35.0    -5.4    152  0.8
  7250   -0.6  30.9   255    7    4  -5.9  -3.2   -0.1  31.7    -7.3    178  0.9
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           12/25/2014 at 0800 MST          |       12/25/2014 at 1100 MST
                                           |
K index... +13.0  LI... -0.1               | K index... -2.9  LI... +2.5
CAPE... +8.6  CIN... -10.9                 | 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 -54.6 -66.3  245  31 16   2.6   1.4 | -55.0 -67.0  235  32 17   3.9   2.2
 45000 -50.5 -58.9  245  55 28   2.4   1.3 | -49.1 -56.4  240  60 31   4.0   2.2
 40000 -55.1 -67.2  230  62 32  -3.7  -2.0 | -55.1 -67.2  225  70 36  -5.1  -2.8
 38000 -56.4 -69.5  225  66 34   4.4   2.4 | -57.2 -71.0  220  75 39   5.2   2.8
 36000 -53.8 -64.8  225  68 35   4.2   2.3 | -54.5 -66.1  225  79 40   4.4   2.4
 34000 -51.3 -60.3  230  70 36   4.2   2.3 | -51.9 -61.4  230  83 43   4.4   2.4
 32000 -48.7 -55.7  230  67 35   4.4   2.4 | -49.6 -57.3  230  76 39   3.6   2.0
 30000 -46.0 -50.8  235  64 33   4.3   2.3 | -47.4 -53.3  230  67 35   3.5   1.9
 29000 -44.4 -47.9  235  62 32   6.0   3.3 | -45.9 -50.6  230  64 33   6.3   3.5
 28000 -42.2 -44.0  235  61 31   6.0   3.3 | -43.9 -47.0  230  63 32   6.4   3.5
 27000 -40.4 -40.7  240  60 31   6.0   3.3 | -41.5 -42.7  235  61 31   6.4   3.5
 26000 -38.3 -36.9  240  58 30   8.1   4.5 | -39.4 -38.9  235  58 30   7.8   4.3
 25000 -35.8 -32.4  240  54 28   8.2   4.5 | -37.1 -34.8  235  55 28   7.8   4.3
 24000 -33.4 -28.1  240  50 26   8.1   4.5 | -34.8 -30.6  240  51 26   7.8   4.3
 23000 -31.0 -23.8  240  46 24   7.4   4.1 | -32.3 -26.1  240  47 24   8.9   4.9
 22000 -28.8 -19.8  245  42 22   7.5   4.1 | -29.7 -21.5  240  43 22   8.8   4.8
 21000 -26.5 -15.7  245  38 19   7.5   4.1 | -27.1 -16.8  235  39 20   8.8   4.8
 20000 -24.3 -11.7  250  35 18   7.2   3.9 | -24.7 -12.5  240  36 19   7.4   4.1
 19500 -23.3  -9.9  250  33 17   7.2   4.0 | -23.5 -10.3  240  36 18   7.4   4.1
 19000 -22.2  -8.0  250  32 17   7.2   4.0 | -22.4  -8.3  240  35 18   7.4   4.1
 18500 -21.1  -6.0  250  31 16   7.3   4.0 | -21.3  -6.3  245  34 18   7.4   4.1
 18000 -20.1  -4.2  255  30 15   8.2   4.5 | -20.2  -4.4  245  34 18   6.8   3.7
 17500 -18.7  -1.7  255  28 14   9.2   5.1 | -19.3  -2.7  250  34 17   6.1   3.3
 17000 -17.3   0.9  250  25 13   9.3   5.1 | -18.4  -1.1  250  33 17   6.0   3.3
 16500 -15.9   3.4  250  24 12   9.6   5.3 | -17.4   0.7  250  33 17   7.3   4.0
 16000 -14.5   5.9  250  22 12   9.6   5.3 | -16.4   2.5  250  32 17   7.2   3.9
 15500 -13.0   8.6  245  21 11   9.7   5.3 | -15.3   4.5  250  32 16   8.1   4.5
 15000 -11.6  11.1  245  20 10   9.7   5.3 | -14.0   6.8  250  31 16   8.4   4.6
 14500 -10.1  13.8  240  19 10   9.6   5.3 | -12.8   9.0  245  30 15   8.9   4.9
 14000  -8.7  16.3  240  18  9   9.3   5.1 | -11.4  11.5  245  29 15   9.4   5.1
 13500  -7.3  18.9  235  17  9   9.1   5.0 | -10.0  14.0  245  29 15   9.5   5.2
 13000  -6.1  21.0  230  16  8   7.8   4.3 |  -8.5  16.7  245  27 14   9.6   5.3
 12500  -5.0  23.0  225  14  7   6.7   3.7 |  -7.1  19.2  240  26 14   8.3   4.5
 12000  -4.1  24.6  225  13  7   7.7   4.2 |  -6.1  21.0  240  25 13   9.1   5.0
 11750  -3.4  25.9  225  13  7   9.2   5.0 |  -5.3  22.5  245  25 13  11.3   6.2
 11500  -2.8  27.0  225  13  7   8.8   4.8 |  -4.5  23.9  245  24 12  10.5   5.7
 11250  -2.1  28.2  225  13  7   8.3   4.6 |  -3.8  25.2  245  24 12   7.3   4.0
 11000  -1.6  29.1  230  14  7   7.5   4.1 |  -3.4  25.9  250  24 12   5.9   3.2
 10750  -1.0  30.2  235  15  8   7.3   4.0 |  -2.8  27.0  255  24 12   7.5   4.1
 10500  -0.5  31.1  245  17  9   7.4   4.0 |  -2.3  27.9  260  25 13   7.3   4.0
 10250   0.4  32.7  250  21 11   5.2   2.8 |  -1.5  29.3  270  27 14   4.2   2.3
 10000   0.8  33.4  255  23 12   3.5   1.9 |  -1.2  29.8  270  28 15   2.8   1.5
  9750   1.0  33.8  260  27 14   1.7   0.9 |  -1.2  29.8  275  31 16   1.2   0.7
  9500   1.1  34.0  265  30 15   2.2   1.2 |  -1.0  30.2  275  31 16   2.6   1.4
  9250   1.3  34.3  265  33 17   2.2   1.2 |  -0.8  30.6  280  30 15   2.8   1.6
  9000   1.4  34.5  265  36 18   1.7   0.9 |  -0.7  30.7  280  28 14   2.9   1.6
  8750   1.5  34.7  265  38 20  -0.2  -0.1 |  -0.4  31.3  280  26 13   4.8   2.6
  8500   1.4  34.5  265  38 20  -0.9  -0.5 |   0.0  32.0  285  23 12   6.7   3.6
  8250   1.3  34.3  265  35 18  -1.7  -1.0 |   0.5  32.9  285  21 11   6.2   3.4
  8000   1.2  34.2  265  32 16   1.7   0.9 |   1.0  33.8  285  19 10   8.0   4.4
  7750   1.3  34.3  265  28 14  -5.8  -3.2 |   1.5  34.7  290  16  8   6.1   3.3
  7500  -0.1  31.8  270  20 10 -29.5 -16.2 |   1.6  34.9  295  12  6  -2.6  -1.4
  7250  -1.8  28.8  275  11  6   5.7   3.1 |   1.6  34.9  300   8  4  14.8   8.1
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/25/2014 at 1400 MST          |       12/25/2014 at 1700 MST
                                           |
K index... -2.5  LI... +2.2                | K index... -0.1  LI... +1.6
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.2
                                           |
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  235  26 13   4.0   2.2 | -54.5 -66.1  235  22 12   3.6   2.0
 45000 -49.3 -56.7  245  56 29   4.1   2.2 | -49.1 -56.4  250  34 17   3.7   2.0
 40000 -53.6 -64.5  225  69 36  -3.9  -2.1 | -51.2 -60.2  230  67 34  -2.2  -1.2
 38000 -55.2 -67.4  220  74 38   4.6   2.5 | -52.3 -62.1  225  79 41   1.4   0.8
 36000 -52.8 -63.0  225  75 38   3.9   2.1 | -51.7 -61.1  225  75 38   1.0   0.6
 34000 -50.5 -58.9  225  75 39   3.9   2.1 | -51.1 -60.0  225  70 36   1.0   0.6
 32000 -48.7 -55.7  225  73 37   2.6   1.4 | -49.8 -57.6  225  69 36   2.5   1.4
 30000 -47.2 -53.0  225  69 36   2.6   1.4 | -48.3 -54.9  225  69 36   2.6   1.4
 29000 -45.9 -50.6  225  67 34   5.5   3.0 | -47.0 -52.6  225  69 35   6.0   3.3
 28000 -44.3 -47.7  230  64 33   5.6   3.1 | -45.2 -49.4  230  68 35   6.1   3.4
 27000 -42.6 -44.7  230  61 31   5.6   3.1 | -43.4 -46.1  230  67 34   6.1   3.4
 26000 -40.3 -40.5  230  58 30   7.6   4.2 | -40.9 -41.6  235  66 34   7.7   4.2
 25000 -38.1 -36.6  235  56 29   7.5   4.1 | -38.7 -37.7  235  65 33   7.5   4.1
 24000 -35.8 -32.4  235  54 28   7.5   4.1 | -36.4 -33.5  240  64 33   7.5   4.1
 23000 -33.6 -28.5  240  53 27   7.5   4.1 | -34.2 -29.6  240  62 32   7.5   4.1
 22000 -31.3 -24.3  240  50 26   7.5   4.1 | -31.9 -25.4  240  58 30   7.5   4.1
 21000 -29.1 -20.4  240  48 25   7.6   4.2 | -29.6 -21.3  240  54 28   7.5   4.1
 20000 -26.6 -15.9  240  44 23   8.7   4.8 | -27.3 -17.1  235  48 25   7.8   4.3
 19500 -25.3 -13.5  240  41 21   8.8   4.8 | -26.2 -15.2  235  45 23   7.8   4.3
 19000 -24.0 -11.2  235  39 20   8.8   4.8 | -25.0 -13.0  235  42 22   7.8   4.3
 18500 -22.7  -8.9  235  36 19   8.7   4.8 | -23.8 -10.8  230  39 20   7.8   4.3
 18000 -21.4  -6.5  230  34 18   8.2   4.5 | -22.7  -8.9  230  36 18   8.0   4.4
 17500 -20.3  -4.5  230  32 16   7.0   3.8 | -21.4  -6.5  225  33 17   8.5   4.7
 17000 -19.3  -2.7  235  29 15   7.1   3.9 | -20.2  -4.4  225  30 15   8.8   4.8
 16500 -18.3  -0.9  235  29 15   5.8   3.2 | -19.0  -2.2  225  28 14   6.2   3.4
 16000 -17.4   0.7  240  30 15   5.9   3.3 | -18.1  -0.6  235  27 14   6.4   3.5
 15500 -16.5   2.3  240  31 16   6.6   3.6 | -17.2   1.0  240  26 14   6.4   3.5
 15000 -15.5   4.1  240  32 17   6.9   3.8 | -16.2   2.8  245  26 13   6.4   3.5
 14500 -14.5   5.9  245  33 17   7.3   4.0 | -15.3   4.5  250  25 13   6.8   3.7
 14000 -13.3   8.1  245  32 17   7.8   4.3 | -14.2   6.4  255  24 13   7.3   4.0
 13500 -12.2  10.0  245  32 16   7.8   4.3 | -13.2   8.2  255  24 13   7.3   4.0
 13000 -11.0  12.2  245  31 16   7.7   4.2 | -12.1  10.2  255  22 11   7.3   4.0
 12500  -9.9  14.2  250  29 15   7.4   4.1 | -11.0  12.2  255  19 10   7.3   4.0
 12000  -9.0  15.8  250  28 14   6.9   3.8 | -10.1  13.8  250  16  8   7.0   3.8
 11750  -8.4  16.9  255  27 14   8.2   4.5 |  -9.5  14.9  250  15  8   7.8   4.3
 11500  -7.9  17.8  255  26 13   7.8   4.3 |  -9.0  15.8  245  13  7   7.4   4.0
 11250  -7.3  18.9  255  25 13   7.1   3.9 |  -8.5  16.7  245  12  6   5.9   3.2
 11000  -6.8  19.8  255  23 12   7.1   3.9 |  -8.1  17.4  245  11  6   5.0   2.8
 10750  -6.3  20.7  255  21 11   8.4   4.6 |  -7.7  18.1  240  10  5   5.4   3.0
 10500  -5.6  21.9  260  19 10   8.4   4.6 |  -7.3  18.9  240  10  5   5.2   2.9
 10250  -5.1  22.8  260  16  8   7.4   4.0 |  -7.0  19.4  235   9  4   4.5   2.4
 10000  -4.1  24.6  265  13  7   7.7   4.2 |  -6.4  20.5  220   6  3   4.3   2.4
  9750  -3.5  25.7  270  11  6   7.8   4.3 |  -6.1  21.0  215   5  2   3.9   2.2
  9500  -3.0  26.6  275   9  5   6.1   3.4 |  -5.8  21.6  195   3  2   3.1   1.7
  9250  -2.5  27.5  285   7  4   5.6   3.1 |  -5.6  21.9  155   3  1   3.0   1.6
  9000  -2.1  28.2  300   6  3   6.1   3.3 |  -5.4  22.3  120   4  2   3.1   1.7
  8750  -1.7  28.9  315   5  3   5.9   3.2 |  -5.1  22.8  105   5  3   3.0   1.6
  8500  -1.3  29.7  335   5  3   5.2   2.9 |  -4.9  23.2  085   6  3   3.0   1.6
  8250  -0.9  30.4  350   6  3   5.5   3.0 |  -4.7  23.5  070   7  3   2.6   1.4
  8000  -0.5  31.1  360   7  4   4.4   2.4 |  -4.5  23.9  060   8  4   4.1   2.2
  7750  -0.3  31.5  005   7  4   4.9   2.7 |  -4.2  24.4  050   8  4   1.3   0.7
  7500   0.2  32.4  015   7  4   9.0   5.0 |  -4.5  23.9  040   6  3  -7.6  -4.2
  7250   0.6  33.1  025   6  3   1.1   0.6 |  -4.8  23.4  015   5  2   9.4   5.2
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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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