Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 261349
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0649 MST Friday, December 26, 2014

This forecast is for Friday, December 26, 2014:

If the trigger temperature of 28.1 F/-2.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 55 ft/min (0.3 m/s)
   Maximum height of thermals.................. 8984 ft MSL (1813 ft AGL)

Forecast maximum temperature................... 17.0 F/-8.8 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1200 MST
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Saturday 12/27..... Poor

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

Remarks...

Sunrise/Sunset.................... 07:16:11 / 16:43:16 MST
Total possible sunshine........... 9 hr 27 min 4 sec (567 min 4 sec)
Altitude of sun at 11:59:42 MST... 27.77 degrees

Upper air data from numerical model forecast valid on 12/26/2014 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 14993 ft MSL (7822 ft AGL)
Lifted condensation level....... 10161 ft MSL (2989 ft AGL)
Lifted index.................... +14.0
K index......................... -4.0

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  -53.8 -64.8   235   28   15   1.7   0.9      M     M       M      M    M
 45000  -51.3 -60.3   225   32   16   1.7   0.9      M     M       M      M    M
 40000  -49.7 -57.5   225   49   25   1.0   0.5      M     M       M      M    M
 38000  -49.1 -56.4   225   58   30   0.1   0.1      M     M       M      M    M
 36000  -49.0 -56.2   220   68   35   0.2   0.1      M     M       M      M    M
 34000  -48.9 -56.0   220   78   40   0.2   0.1      M     M       M      M    M
 32000  -49.0 -56.2   215   78   40  -0.5  -0.3      M     M       M      M    M
 30000  -49.3 -56.7   210   73   38  -0.4  -0.2      M     M       M      M    M
 29000  -48.9 -56.0   210   71   37   5.3   2.9   19.2  66.6    21.1      M    M
 28000  -47.4 -53.3   210   69   35   4.9   2.7   17.2  63.0    19.9      M    M
 27000  -45.9 -50.6   210   66   34   4.9   2.7   15.4  59.7    18.7      M    M
 26000  -44.4 -47.9   210   64   33   6.0   3.3   13.7  56.7    17.6      M    M
 25000  -42.2 -44.0   210   62   32   7.5   4.1   12.7  54.9    17.0      M    M
 24000  -39.4 -38.9   210   59   31   7.5   4.1   11.7  53.1    16.4      M    M
 23000  -37.1 -34.8   215   57   29   8.8   4.9   11.1  51.9    16.1      M    M
 22000  -34.4 -29.9   215   56   29   8.9   4.9   10.7  51.2    16.0      M    M
 21000  -31.8 -25.2   215   55   28   8.9   4.9   10.4  50.7    15.9      M    M
 20000  -29.3 -20.7   215   53   27   7.6   4.2    9.9  49.8    15.7      M    M
 19500  -28.1 -18.6   215   51   26   7.6   4.2    9.5  49.1    15.5      M    M
 19000  -27.0 -16.6   215   49   25   7.6   4.2    9.1  48.5    15.2      M    M
 18500  -25.9 -14.6   220   47   24   7.5   4.1    8.8  47.8    15.0      M    M
 18000  -24.7 -12.5   220   46   23   6.4   3.5    8.5  47.3    14.8      M    M
 17500  -24.2 -11.6   220   43   22   2.5   1.4    7.5  45.4    14.0      M    M
 17000  -23.8 -10.8   220   40   21   2.3   1.3    6.3  43.3    13.0      M    M
 16500  -23.1  -9.6   215   38   19   7.7   4.2    5.5  41.8    12.3      M    M
 16000  -22.0  -7.6   215   36   18   7.6   4.2    5.1  41.2    12.0      M    M
 15500  -20.9  -5.6   210   33   17   8.3   4.5    4.8  40.6    11.7      M    M
 15000  -19.6  -3.3   210   31   16   8.4   4.6    4.6  40.2    11.6      M    M
 14500  -18.4  -1.1   210   29   15   6.3   3.5    4.4  39.9    11.5      M    M
 14000  -17.8  -0.0   210   26   13   3.2   1.8    3.4  38.0    10.6      M    M
 13500  -17.4   0.7   210   24   12   3.1   1.7    2.3  36.2     9.6      M    M
 13000  -16.9   1.6   210   20   10   2.9   1.6    1.2  34.2     8.7      M    M
 12500  -16.5   2.3   215   16    8   3.3   1.8    0.1  32.2     7.7      M    M
 12000  -15.9   3.4   220   13    7   5.0   2.7   -0.7  30.7     6.9      M    M
 11750  -15.5   4.1   220   11    6   4.5   2.5   -1.1  29.9     6.6      M    M
 11500  -15.2   4.6   220    8    4   5.5   3.0   -1.5  29.2     6.2      M    M
 11250  -14.7   5.5   225    6    3   7.7   4.2   -1.8  28.8     6.0      M    M
 11000  -14.1   6.6   225    4    2   7.9   4.4   -1.9  28.5     5.9      M    M
 10750  -13.5   7.7   240    2    1   8.7   4.8   -2.0  28.3     5.8      M    M
 10500  -12.9   8.8   265    1    0   3.5   1.9   -2.2  28.0     5.6      M    M
 10250  -13.0   8.6   330    4    2  -3.6  -2.0   -3.1  26.5     4.8      M    M
 10000  -13.2   8.2   330    8    4  -2.6  -1.5   -4.1  24.6     3.8      M    M
  9750  -14.1   6.6   330   17    9  -3.6  -2.0   -6.5  20.3     1.6      M    M
  9500  -13.9   7.0   340   17    9   3.3   1.8   -7.1  19.2     1.0      M    M
  9250  -13.8   7.2   345   17    9   1.1   0.6   -7.7  18.1     0.4      M    M
  9000  -13.7   7.3   350   17    9   3.0   1.6   -8.3  17.0    -0.2    250  1.3
  8750  -13.4   7.9   355   16    8   5.4   3.0   -8.7  16.3    -0.6    233  1.2
  8500  -12.9   8.8   355   16    8   5.8   3.2   -9.0  15.7    -0.9    213  1.1
  8250  -12.5   9.5   355   15    8   5.8   3.2   -9.3  15.2    -1.3    193  1.0
  8000  -12.1  10.2   360   15    8   5.5   3.0   -9.6  14.7    -1.6    173  0.9
  7750  -11.7  10.9   360   14    7   6.1   3.3  -10.0  14.1    -1.9    153  0.8
  7500  -11.2  11.8   360   12    6   8.0   4.4  -10.2  13.7    -2.1    130  0.7
  7250  -10.6  12.9   360    9    5   4.3   2.3  -10.4  13.4    -2.3    107  0.5
  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 * * * * * *

           12/26/2014 at 0800 MST          |       12/26/2014 at 1100 MST
                                           |
K index... +2.4  LI... +2.6                | K index... +4.9  LI... +1.3
CAPE... 0.0  CIN... M                      | 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 -52.9 -63.2  230  32 16   1.3   0.7 | -52.1 -61.8  230  35 18   0.8   0.5
 45000 -50.9 -59.6  220  34 18   1.3   0.7 | -50.9 -59.6  225  42 22   0.8   0.5
 40000 -48.6 -55.5  220  50 26   1.5   0.8 | -48.5 -55.3  225  55 28   1.8   1.0
 38000 -47.7 -53.9  220  57 29   0.9   0.5 | -47.4 -53.3  225  60 31   0.0   0.0
 36000 -47.9 -54.2  220  57 29  -0.4  -0.2 | -47.5 -53.5  220  56 29  -0.2  -0.1
 34000 -48.1 -54.6  220  57 30  -0.4  -0.2 | -47.6 -53.7  215  53 27  -0.2  -0.1
 32000 -48.5 -55.3  215  59 30  -0.9  -0.5 | -47.5 -53.5  210  53 27   0.2   0.1
 30000 -49.1 -56.4  210  62 32  -0.9  -0.5 | -47.4 -53.3  210  56 29   0.2   0.1
 29000 -48.9 -56.0  210  62 32   5.0   2.8 | -47.1 -52.8  210  57 29   3.0   1.6
 28000 -47.6 -53.7  210  60 31   4.4   2.4 | -46.3 -51.3  205  58 30   2.8   1.5
 27000 -46.3 -51.3  205  57 30   4.4   2.4 | -45.5 -49.9  205  59 31   2.8   1.5
 26000 -44.9 -48.8  205  55 28   4.9   2.7 | -44.6 -48.3  200  61 31   2.8   1.6
 25000 -43.0 -45.4  205  53 27   6.9   3.8 | -43.0 -45.4  200  61 31   5.9   3.2
 24000 -40.9 -41.6  205  51 26   6.9   3.8 | -40.8 -41.4  200  60 31   5.9   3.2
 23000 -38.3 -36.9  205  48 25   7.7   4.2 | -39.1 -38.4  200  60 31   6.2   3.4
 22000 -36.0 -32.8  205  46 24   7.9   4.3 | -37.2 -35.0  205  53 27   6.4   3.5
 21000 -33.6 -28.5  205  44 23   7.9   4.3 | -35.3 -31.5  205  46 24   6.4   3.5
 20000 -31.4 -24.5  210  42 22   6.4   3.5 | -33.3 -27.9  205  40 20   6.4   3.5
 19500 -30.4 -22.7  210  40 21   6.5   3.6 | -32.4 -26.3  205  36 19   6.5   3.5
 19000 -29.5 -21.1  210  38 20   6.5   3.6 | -31.4 -24.5  205  33 17   6.5   3.6
 18500 -28.5 -19.3  215  37 19   6.5   3.6 | -30.5 -22.9  205  29 15   6.5   3.6
 18000 -27.5 -17.5  215  35 18   6.4   3.5 | -29.5 -21.1  205  26 13   6.6   3.6
 17500 -26.6 -15.9  215  33 17   6.1   3.4 | -28.4 -19.1  205  24 12   8.0   4.4
 17000 -25.7 -14.3  220  30 16   6.1   3.3 | -27.2 -17.0  205  23 12   7.8   4.3
 16500 -24.7 -12.5  220  28 15   7.4   4.1 | -26.0 -14.8  200  22 11   8.7   4.8
 16000 -23.6 -10.5  215  27 14   7.5   4.1 | -24.7 -12.5  200  22 11   8.8   4.8
 15500 -22.5  -8.5  215  27 14   8.1   4.5 | -23.4 -10.1  200  22 11   8.5   4.7
 15000 -21.2  -6.2  210  26 13   8.4   4.6 | -22.2  -8.0  200  22 11   8.3   4.5
 14500 -20.0  -4.0  210  26 13   7.0   3.8 | -21.0  -5.8  200  22 11   7.6   4.2
 14000 -19.3  -2.7  210  24 12   4.5   2.5 | -20.0  -4.0  200  20 10   6.4   3.5
 13500 -18.6  -1.5  205  23 12   4.5   2.5 | -19.0  -2.2  205  18  9   5.6   3.1
 13000 -17.9  -0.2  205  20 10   4.4   2.4 | -18.4  -1.1  205  15  8   3.2   1.8
 12500 -17.3   0.9  205  17  9   4.5   2.5 | -18.0  -0.4  205  12  6   3.1   1.7
 12000 -16.6   2.1  200  14  7   4.6   2.6 | -17.6   0.3  200   9  5   2.4   1.3
 11750 -16.3   2.7  200  12  6   2.5   1.3 | -17.4   0.7  195   8  4   2.2   1.2
 11500 -16.1   3.0  190  10  5   2.1   1.1 | -17.2   1.0  185   7  4   2.1   1.1
 11250 -15.9   3.4  185   9  4   3.6   2.0 | -17.1   1.2  170   6  3   1.8   1.0
 11000 -15.6   3.9  175   7  4   4.2   2.3 | -16.9   1.6  150   4  2   2.9   1.6
 10750 -15.4   4.3  165   6  3   2.8   1.5 | -16.8   1.8  110   3  2  -1.4  -0.8
 10500 -15.3   4.5  150   5  3  -1.2  -0.7 | -17.1   1.2  070   4  2  -2.5  -1.4
 10250 -15.5   4.1  110   3  1  -3.8  -2.1 | -17.0   1.4  045   5  3   1.7   0.9
 10000 -15.8   3.6  040   4  2  -2.9  -1.6 | -16.9   1.6  035   7  4   1.8   1.0
  9750 -16.5   2.3  015  13  7  -0.7  -0.4 | -16.7   1.9  025  12  6   4.4   2.4
  9500 -16.1   3.0  015  13  7   6.6   3.6 | -16.1   3.0  020  12  6   8.8   4.8
  9250 -15.7   3.7  015  13  7   4.7   2.6 | -15.5   4.1  015  12  6   7.6   4.2
  9000 -15.3   4.5  015  14  7   5.2   2.8 | -15.0   5.0  010  12  6   8.0   4.4
  8750 -14.9   5.2  015  14  7   7.7   4.2 | -14.3   6.3  010  12  6   9.5   5.2
  8500 -14.2   6.4  015  13  7   9.8   5.4 | -13.6   7.5  010  12  6  10.4   5.7
  8250 -13.5   7.7  015  13  7   9.3   5.1 | -12.8   9.0  010  12  6  10.3   5.7
  8000 -12.8   9.0  015  13  7   9.4   5.1 | -12.1  10.2  010  11  6   9.8   5.4
  7750 -12.1  10.2  010  12  6  10.8   5.9 | -11.3  11.7  010  11  6  12.5   6.9
  7500 -11.2  11.8  010  11  5  13.6   7.4 | -10.1  13.8  010  10  5  18.8  10.3
  7250 -10.3  13.5  010   9  5   8.5   4.7 |  -9.0  15.8  010   9  5   7.2   4.0
  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

           12/26/2014 at 1400 MST          |       12/26/2014 at 1700 MST
                                           |
K index... +2.8  LI... +1.1                | K index... +4.9  LI... +1.6
CAPE... 0.0  CIN... M                      | 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 -52.2 -62.0  230  34 17   1.0   0.6 | -53.0 -63.4  230  34 17   2.0   1.1
 45000 -50.7 -59.3  230  41 21   1.0   0.6 | -49.9 -57.8  230  33 17   2.0   1.1
 40000 -47.6 -53.7  230  48 25   2.3   1.2 | -46.6 -51.9  230  39 20   2.1   1.1
 38000 -46.1 -51.0  230  52 27   0.7   0.4 | -45.4 -49.7  230  42 22   1.3   0.7
 36000 -45.8 -50.4  225  52 27   0.5   0.3 | -44.7 -48.5  225  44 23   1.2   0.6
 34000 -45.5 -49.9  215  53 27   0.5   0.3 | -44.0 -47.2  225  46 24   1.2   0.6
 32000 -45.0 -49.0  210  52 27   0.9   0.5 | -43.8 -46.8  225  43 22  -0.3  -0.1
 30000 -44.5 -48.1  210  50 26   0.9   0.5 | -44.0 -47.2  225  36 19  -0.2  -0.1
 29000 -44.3 -47.7  210  48 25  -0.5  -0.3 | -44.1 -47.4  225  33 17  -2.0  -1.1
 28000 -44.5 -48.1  205  46 24  -0.8  -0.4 | -44.9 -48.8  225  29 15  -2.7  -1.5
 27000 -44.8 -48.6  205  44 22  -0.8  -0.4 | -45.7 -50.3  225  25 13  -2.7  -1.5
 26000 -45.0 -49.0  200  41 21  -1.2  -0.7 | -46.6 -51.9  230  21 11  -3.3  -1.8
 25000 -44.3 -47.7  200  39 20   3.7   2.0 | -45.6 -50.1  235  18  9   4.3   2.4
 24000 -43.0 -45.4  200  35 18   3.7   2.0 | -44.4 -47.9  240  16  8   4.3   2.4
 23000 -41.9 -43.4  200  33 17   4.8   2.7 | -43.1 -45.6  245  14  7   5.7   3.1
 22000 -39.9 -39.8  200  28 14   6.7   3.7 | -40.8 -41.4  240  15  8   7.8   4.3
 21000 -37.9 -36.2  205  23 12   6.7   3.7 | -38.4 -37.1  235  15  8   7.8   4.3
 20000 -35.8 -32.4  205  20 10   8.8   4.8 | -36.1 -33.0  235  16  8   8.2   4.5
 19500 -34.5 -30.1  205  19 10   8.6   4.7 | -34.9 -30.8  240  16  8   8.2   4.5
 19000 -33.2 -27.8  205  19 10   8.6   4.7 | -33.6 -28.5  245  16  8   8.2   4.5
 18500 -31.9 -25.4  205  19 10   8.6   4.7 | -32.4 -26.3  250  16  8   8.2   4.5
 18000 -30.7 -23.3  205  19 10   8.6   4.7 | -31.2 -24.2  255  16  8   8.2   4.5
 17500 -29.4 -20.9  205  19 10   8.7   4.8 | -30.0 -22.0  260  16  8   8.2   4.5
 17000 -28.1 -18.6  210  18  9   8.7   4.8 | -28.8 -19.8  265  16  8   8.2   4.5
 16500 -26.8 -16.2  210  18  9   8.5   4.7 | -27.6 -17.7  270  16  8   7.8   4.3
 16000 -25.5 -13.9  220  17  9   8.5   4.7 | -26.4 -15.5  270  16  8   7.8   4.3
 15500 -24.3 -11.7  225  17  9   8.4   4.6 | -25.3 -13.5  270  16  8   7.8   4.3
 15000 -23.0  -9.4  225  17  9   8.2   4.5 | -24.1 -11.4  270  16  8   7.7   4.2
 14500 -21.8  -7.2  225  17  9   7.8   4.3 | -23.0  -9.4  270  16  8   7.8   4.3
 14000 -20.8  -5.4  230  15  8   6.7   3.7 | -21.8  -7.2  270  15  8   7.8   4.3
 13500 -19.8  -3.6  235  13  7   6.2   3.4 | -20.6  -5.1  275  14  7   7.3   4.0
 13000 -19.1  -2.4  235  11  6   3.8   2.1 | -19.7  -3.5  275  13  7   5.8   3.2
 12500 -18.5  -1.3  240   9  5   3.4   1.9 | -18.8  -1.8  275  11  6   4.9   2.7
 12000 -18.3  -0.9  240   7  4  -0.4  -0.2 | -18.4  -1.1  280  10  5   1.6   0.9
 11750 -18.3  -0.9  245   6  3  -0.1  -0.0 | -18.4  -1.1  280   9  4  -0.1  -0.0
 11500 -18.3  -0.9  240   5  3   0.7   0.4 | -18.4  -1.1  280   7  4  -0.0  -0.0
 11250 -18.2  -0.8  250   4  2   2.5   1.4 | -18.3  -0.9  290   6  3   2.1   1.1
 11000 -18.0  -0.4  285   2  1   3.2   1.7 | -18.1  -0.6  310   6  3   2.4   1.3
 10750 -17.8  -0.0  340   3  1   2.9   1.6 | -18.0  -0.4  325   7  3   1.4   0.8
 10500 -17.5   0.5  005   5  3   4.2   2.3 | -17.9  -0.2  340   7  4   2.7   1.5
 10250 -17.2   1.0  010   7  3   5.7   3.1 | -17.6   0.3  345   8  4   4.5   2.5
 10000 -16.7   1.9  015   8  4   5.9   3.2 | -16.9   1.6  355  11  5   2.3   1.2
  9750 -15.9   3.4  015  11  5   6.7   3.7 | -16.8   1.8  355  12  6   4.8   2.6
  9500 -15.3   4.5  015  11  6   8.5   4.6 | -16.2   2.8  360  12  6   9.3   5.1
  9250 -14.7   5.5  015  12  6   7.9   4.3 | -15.6   3.9  360  12  6   8.2   4.5
  9000 -14.1   6.6  015  13  6   8.5   4.7 | -14.9   5.2  005  12  6   8.1   4.5
  8750 -13.5   7.7  020  13  6   9.8   5.4 | -14.3   6.3  005  12  6   9.3   5.1
  8500 -12.7   9.1  020  12  6  10.2   5.6 | -13.6   7.5  010  12  6  10.7   5.9
  8250 -12.0  10.4  020  12  6  10.2   5.6 | -12.8   9.0  010  11  6  10.4   5.7
  8000 -11.2  11.8  020  12  6   9.4   5.2 | -12.0  10.4  015  11  6   9.8   5.4
  7750 -10.5  13.1  020  11  6  11.7   6.4 | -11.3  11.7  015  11  6  10.5   5.7
  7500  -9.4  15.1  020  11  5  18.0   9.9 | -10.4  13.3  015   9  5  12.8   7.0
  7250  -8.3  17.1  025  10  5   6.2   3.4 |  -9.6  14.7  015   8  4   8.2   4.5
  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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