Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 281122
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0422 MST Sunday, December 28, 2014

This forecast is for Sunday, December 28, 2014:

If the trigger temperature of 37.2 F/2.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 215 ft/min (1.1 m/s)
   Maximum height of thermals.................. 9427 ft MSL (2669 ft AGL)

Forecast maximum temperature................... 34.0 F/1.6 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7933 ft MSL (1176 ft AGL)
Thermal soaring outlook for Monday 12/29....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:16:49 / 16:44:37 MST
Total possible sunshine........... 9 hr 27 min 47 sec (567 min 47 sec)
Altitude of sun at 12:00:40 MST... 27.86 degrees

Upper air data from numerical model forecast valid on 12/28/2014 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 17541 ft MSL (10783 ft AGL)
Lifted condensation level....... 13998 ft MSL (7240 ft AGL)
Lifted index.................... +9.5
K index......................... +7.0

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  -56.9 -70.4   270   37   19   0.5   0.3      M     M       M      M    M
 45000  -56.1 -69.0   280   39   20   0.5   0.3      M     M       M      M    M
 40000  -55.1 -67.2   285   54   28   0.7   0.4      M     M       M      M    M
 38000  -54.7 -66.5   290   61   31   0.9   0.5      M     M       M      M    M
 36000  -54.2 -65.6   300   71   37   0.8   0.5      M     M       M      M    M
 34000  -53.6 -64.5   310   86   44   1.6   0.9      M     M       M      M    M
 32000  -50.1 -58.2   305   81   42   6.3   3.5      M     M       M      M    M
 30000  -46.3 -51.3   305   76   39   5.9   3.3      M     M       M      M    M
 29000  -44.9 -48.8   300   70   36   4.5   2.4   22.7  72.8    16.6      M    M
 28000  -43.6 -46.5   300   64   33   4.5   2.5   20.6  69.1    15.2      M    M
 27000  -42.2 -44.0   295   58   30   4.6   2.5   18.7  65.6    13.9      M    M
 26000  -40.5 -40.9   295   54   28   7.3   4.0   17.2  63.0    12.9      M    M
 25000  -38.3 -36.9   290   50   26   7.3   4.0   16.2  61.2    12.2      M    M
 24000  -36.1 -33.0   290   46   24   7.3   4.0   15.4  59.6    11.7      M    M
 23000  -34.0 -29.2   285   43   22   7.2   4.0   14.5  58.1    11.1      M    M
 22000  -31.8 -25.2   290   41   21   7.2   4.0   13.5  56.3    10.4      M    M
 21000  -29.6 -21.3   290   38   20   7.2   4.0   12.7  54.8     9.8      M    M
 20000  -27.5 -17.5   295   36   18   7.3   4.0   11.8  53.2     9.1      M    M
 19500  -26.4 -15.5   295   34   18   7.3   4.0   11.3  52.4     8.8      M    M
 19000  -25.3 -13.5   295   33   17   7.3   4.0   10.9  51.7     8.5      M    M
 18500  -24.2 -11.6   295   32   16   7.3   4.0   10.5  51.0     8.1      M    M
 18000  -23.1  -9.6   295   30   16   7.4   4.1   10.2  50.3     7.9      M    M
 17500  -22.0  -7.6   295   29   15   7.5   4.1    9.8  49.6     7.5      M    M
 17000  -20.9  -5.6   295   28   15   7.5   4.1    9.4  48.9     7.2      M    M
 16500  -19.2  -2.6   295   27   14   7.4   4.1    8.8  47.8     6.8      M    M
 16000  -18.1  -0.6   295   27   14   7.4   4.0    8.4  47.2     6.5      M    M
 15500  -17.0   1.4   295   26   13   7.3   4.0    8.0  46.4     6.1      M    M
 15000  -15.9   3.4   295   25   13   7.1   3.9    7.6  45.7     5.8      M    M
 14500  -14.9   5.2   295   24   13   6.6   3.6    7.1  44.8     5.3      M    M
 14000  -13.9   7.0   295   24   12   6.6   3.6    6.6  43.9     4.9      M    M
 13500  -13.0   8.6   295   23   12   6.4   3.5    6.1  42.9     4.4      M    M
 13000  -12.0  10.4   295   23   12   6.4   3.5    5.5  41.9     3.9      M    M
 12500  -11.0  12.2   295   22   11   7.0   3.8    5.0  41.0     3.5      M    M
 12000  -10.0  14.0   295   21   11   6.3   3.4    4.5  40.2     3.0      M    M
 11750   -9.6  14.7   295   21   11   5.8   3.2    4.2  39.6     2.8      M    M
 11500   -9.2  15.4   295   21   11   5.7   3.1    3.9  39.1     2.5      M    M
 11250   -8.7  16.3   295   20   10   5.6   3.0    3.6  38.5     2.2      M    M
 11000   -8.3  17.1   290   19   10   6.3   3.4    3.3  37.9     1.9      M    M
 10750   -7.8  18.0   290   19   10   6.5   3.5    3.0  37.5     1.6      M    M
 10500   -7.4  18.7   290   18   10   5.7   3.2    2.7  36.9     1.3      M    M
 10250   -6.9  19.6   290   18    9   6.3   3.4    2.4  36.4     1.1      M    M
 10000   -6.5  20.3   290   17    9   4.9   2.7    2.2  35.9     0.8      M    M
  9750   -6.1  21.0   285   15    8   4.7   2.6    1.7  35.1     0.4      M    M
  9500   -5.7  21.7   285   15    8   5.7   3.1    1.4  34.5     0.1      M    M
  9250   -5.3  22.5   285   14    7   5.6   3.1    1.1  33.9    -0.3    199  1.0
  9000   -4.9  23.2   285   14    7   4.8   2.6    0.8  33.4    -0.6    179  0.9
  8750   -4.6  23.7   290   13    7   3.7   2.0    0.3  32.6    -1.0    162  0.8
  8500   -4.3  24.3   285   12    6   3.9   2.2   -0.1  31.7    -1.5    146  0.7
  8250   -4.0  24.8   285   12    6   3.4   1.9   -0.6  30.9    -1.9    130  0.7
  8000   -4.0  24.8   285   12    6  -6.2  -3.4   -1.3  29.6    -2.6    123  0.6
  7750   -4.8  23.4   285   11    6 -11.4  -6.3   -2.9  26.8    -4.2    140  0.7
  7500   -5.4  22.3   280   10    5  -3.2  -1.7   -4.2  24.4    -5.5    149  0.8
  7250   -5.8  21.6   275    9    4 -15.8  -8.7   -5.4  22.3    -6.7    155  0.8
  7000   -8.3  17.1   280    8    4 -47.4 -26.0   -8.0  17.7    -9.3    221  1.1
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           12/28/2014 at 0800 MST          |       12/28/2014 at 1100 MST
                                           |
K index... +10.2  LI... +2.8               | K index... +3.4  LI... +3.3
CAPE... 0.0  CIN... -1.0                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -56.1 -69.0  265  40 21   1.4   0.8 | -55.7 -68.3  265  50 26   1.7   0.9
 45000 -54.0 -65.2  275  39 20   1.4   0.8 | -53.2 -63.8  270  67 34   1.6   0.9
 40000 -54.4 -65.9  280  64 33  -0.5  -0.3 | -54.3 -65.7  275  79 41  -1.1  -0.6
 38000 -54.5 -66.1  285  75 39   1.4   0.8 | -54.8 -66.6  280  84 43   0.7   0.4
 36000 -53.8 -64.8  290  84 43   1.2   0.7 | -54.4 -65.9  280  91 47   0.6   0.3
 34000 -52.9 -63.2  295  95 49   1.3   0.7 | -54.0 -65.2  285  98 51   0.1   0.1
 32000 -49.9 -57.8  295  92 48   5.4   3.0 | -51.3 -60.3  285  95 49   5.1   2.8
 30000 -46.6 -51.9  295  89 46   5.4   2.9 | -48.3 -54.9  280  89 46   5.1   2.8
 29000 -45.2 -49.4  290  82 42   4.5   2.5 | -46.5 -51.7  280  83 43   6.2   3.4
 28000 -43.9 -47.0  290  74 38   4.5   2.5 | -44.6 -48.3  280  77 40   6.2   3.4
 27000 -42.5 -44.5  285  66 34   4.6   2.5 | -42.8 -45.0  280  70 36   6.2   3.4
 26000 -40.8 -41.4  285  59 30   7.1   3.9 | -40.9 -41.6  280  65 33   6.6   3.6
 25000 -38.7 -37.7  280  52 27   7.1   3.9 | -38.9 -38.0  275  61 31   6.5   3.6
 24000 -36.6 -33.9  275  46 24   7.1   3.9 | -37.0 -34.6  270  57 29   6.6   3.6
 23000 -34.4 -29.9  270  42 21   7.6   4.2 | -34.9 -30.8  265  54 28   7.9   4.3
 22000 -32.2 -26.0  270  40 21   7.6   4.1 | -32.5 -26.5  265  49 25   7.8   4.3
 21000 -29.9 -21.8  270  38 20   7.6   4.1 | -30.2 -22.4  260  45 23   7.8   4.3
 20000 -27.6 -17.7  275  36 19   7.7   4.2 | -27.9 -18.2  260  42 21   7.6   4.1
 19500 -26.5 -15.7  275  36 18   7.7   4.2 | -26.8 -16.2  265  40 20   7.6   4.1
 19000 -25.4 -13.7  275  35 18   7.7   4.2 | -25.6 -14.1  265  38 19   7.6   4.1
 18500 -24.2 -11.6  280  34 18   7.7   4.2 | -24.5 -12.1  270  36 19   7.6   4.2
 18000 -23.1  -9.6  280  34 17   7.3   4.0 | -23.4 -10.1  275  35 18   7.2   4.0
 17500 -22.0  -7.6  285  32 17   7.0   3.9 | -22.3  -8.1  280  32 16   7.0   3.9
 17000 -21.0  -5.8  285  31 16   7.0   3.8 | -21.3  -6.3  285  30 15   7.0   3.9
 16500 -20.0  -4.0  290  31 16   6.6   3.6 | -20.2  -4.4  290  29 15   7.1   3.9
 16000 -18.5  -1.3  290  30 15   6.6   3.6 | -18.6  -1.5  295  30 15   7.1   3.9
 15500 -17.5   0.5  295  29 15   6.5   3.6 | -17.6   0.3  300  29 15   7.0   3.8
 15000 -16.6   2.1  295  29 15   6.5   3.6 | -16.6   2.1  305  29 15   6.9   3.8
 14500 -15.6   3.9  300  29 15   6.6   3.6 | -15.6   3.9  310  29 15   5.9   3.3
 14000 -14.6   5.7  300  29 15   6.6   3.6 | -14.7   5.5  310  29 15   6.0   3.3
 13500 -13.6   7.5  305  28 15   6.5   3.5 | -13.8   7.2  315  28 15   6.1   3.3
 13000 -12.7   9.1  305  28 14   6.5   3.6 | -12.9   8.8  315  28 14   6.1   3.4
 12500 -11.7  10.9  305  28 14   6.6   3.6 | -12.1  10.2  315  27 14   5.8   3.2
 12000 -10.8  12.6  305  27 14   5.0   2.8 | -11.2  11.8  320  26 14   4.6   2.5
 11750 -10.4  13.3  310  27 14   5.3   2.9 | -10.9  12.4  320  26 13   4.5   2.5
 11500 -10.0  14.0  310  26 13   6.0   3.3 | -10.6  12.9  320  25 13   4.8   2.6
 11250  -9.5  14.9  310  26 13   6.1   3.4 | -10.2  13.6  320  25 13   4.9   2.7
 11000  -9.1  15.6  310  25 13   5.1   2.8 |  -9.9  14.2  320  24 12   4.4   2.4
 10750  -8.8  16.2  310  24 13   5.2   2.8 |  -9.5  14.9  320  23 12   4.4   2.4
 10500  -8.3  17.1  310  24 12   6.3   3.4 |  -9.2  15.4  320  21 11   4.9   2.7
 10250  -7.8  18.0  310  23 12   6.1   3.3 |  -8.8  16.2  320  20 10   4.6   2.5
 10000  -7.4  18.7  310  22 11   5.8   3.2 |  -8.5  16.7  320  19 10   5.2   2.9
  9750  -7.0  19.4  310  21 11   5.7   3.1 |  -8.0  17.6  315  17  9   6.0   3.3
  9500  -6.5  20.3  310  19 10   5.9   3.2 |  -7.6  18.3  315  15  8   6.1   3.3
  9250  -6.1  21.0  310  18  9   6.1   3.3 |  -7.1  19.2  315  14  7   6.1   3.4
  9000  -5.6  21.9  310  17  9   5.2   2.8 |  -6.7  19.9  315  12  6   6.0   3.3
  8750  -5.3  22.5  315  16  8   4.1   2.3 |  -6.3  20.7  315  11  6   5.0   2.7
  8500  -5.0  23.0  315  15  8   4.3   2.3 |  -5.9  21.4  315  10  5   4.3   2.4
  8250  -4.6  23.7  315  14  7   4.3   2.4 |  -5.6  21.9  310   8  4   4.5   2.4
  8000  -4.5  23.9  320  14  7  -2.1  -1.2 |  -5.3  22.5  310   7  4   4.4   2.4
  7750  -4.9  23.2  315  14  7  -5.1  -2.8 |  -5.0  23.0  315   7  3   4.7   2.6
  7500  -5.1  22.8  315  13  7   0.1   0.1 |  -4.6  23.7  320   6  3   5.2   2.9
  7250  -5.1  22.8  310  11  6  -4.8  -2.6 |  -4.3  24.3  315   5  2   4.9   2.7
  7000  -6.0  21.2  305   9  5 -16.9  -9.3 |  -4.0  24.8  315   4  2   4.0   2.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/28/2014 at 1400 MST          |       12/28/2014 at 1700 MST
                                           |
K index... -13.5  LI... +3.1               | K index... -7.3  LI... +1.8
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 -54.5 -66.1  275  39 20  -0.0  -0.0 | -55.0 -67.0  290  32 16   0.5   0.3
 45000 -54.5 -66.1  280  70 36  -0.0  -0.0 | -54.3 -65.7  280  56 29   0.5   0.3
 40000 -54.3 -65.7  280  78 40   0.2   0.1 | -53.7 -64.7  280  67 35   0.4   0.2
 38000 -54.2 -65.6  280  79 41   0.8   0.4 | -53.4 -64.1  285  71 36   1.7   1.0
 36000 -53.6 -64.5  280  85 44   0.9   0.5 | -52.1 -61.8  280  81 42   1.9   1.0
 34000 -53.1 -63.6  280  89 46   0.7   0.4 | -51.0 -59.8  280  90 46   1.9   1.0
 32000 -50.8 -59.4  280  87 45   4.4   2.4 | -49.7 -57.5  280  89 46   2.3   1.3
 30000 -48.2 -54.8  280  82 42   4.2   2.3 | -48.3 -54.9  285  85 44   2.1   1.1
 29000 -46.2 -51.2  280  80 41   7.3   4.0 | -46.7 -52.1  285  85 44   7.2   4.0
 28000 -44.0 -47.2  285  78 40   7.4   4.0 | -44.5 -48.1  285  86 44   7.3   4.0
 27000 -41.8 -43.2  285  77 39   7.4   4.0 | -42.3 -44.1  285  87 45   7.3   4.0
 26000 -39.8 -39.6  285  75 38   5.2   2.9 | -40.2 -40.4  285  88 45   6.4   3.5
 25000 -38.2 -36.8  285  71 36   5.3   2.9 | -38.3 -36.9  285  85 44   6.3   3.5
 24000 -36.6 -33.9  285  67 35   5.3   2.9 | -36.4 -33.5  290  83 43   6.3   3.5
 23000 -34.6 -30.3  285  62 32   5.3   2.9 | -34.2 -29.6  290  78 40   4.5   2.5
 22000 -33.0 -27.4  285  59 30   5.3   2.9 | -32.8 -27.0  290  73 38   4.6   2.5
 21000 -31.4 -24.5  285  55 28   5.2   2.9 | -31.5 -24.7  290  67 35   4.6   2.5
 20000 -29.3 -20.7  285  52 27   8.1   4.4 | -30.0 -22.0  295  61 31   5.3   2.9
 19500 -28.1 -18.6  285  51 26   8.1   4.5 | -29.2 -20.6  295  58 30   5.4   2.9
 19000 -26.8 -16.2  285  50 26   8.1   4.5 | -28.4 -19.1  295  54 28   5.4   2.9
 18500 -25.6 -14.1  285  49 25   8.2   4.5 | -27.6 -17.7  295  51 26   5.4   2.9
 18000 -24.4 -11.9  285  48 25   7.2   4.0 | -26.8 -16.2  295  47 24   5.8   3.2
 17500 -23.4 -10.1  285  47 24   7.0   3.8 | -25.9 -14.6  295  44 23   6.0   3.3
 17000 -22.4  -8.3  285  47 24   7.5   4.1 | -25.0 -13.0  295  40 21   6.4   3.5
 16500 -21.1  -6.0  285  43 22   9.0   5.0 | -23.8 -10.8  295  37 19   8.2   4.5
 16000 -19.8  -3.6  280  38 20   9.2   5.0 | -22.6  -8.7  295  33 17   8.0   4.4
 15500 -18.6  -1.5  275  35 18   7.1   3.9 | -21.4  -6.5  290  31 16   9.0   4.9
 15000 -17.5   0.5  270  33 17   7.4   4.1 | -20.1  -4.2  290  30 15   8.9   4.9
 14500 -16.5   2.3  270  32 17   6.0   3.3 | -18.7  -1.7  290  30 16   8.9   4.9
 14000 -15.6   3.9  280  34 17   5.9   3.2 | -17.4   0.7  290  32 16   8.9   4.9
 13500 -14.8   5.4  285  36 18   5.7   3.1 | -16.1   3.0  290  33 17   8.7   4.8
 13000 -13.9   7.0  290  36 19   5.6   3.1 | -14.8   5.4  290  34 18   8.6   4.7
 12500 -13.1   8.4  290  37 19   6.6   3.6 | -13.5   7.7  290  35 18   8.7   4.8
 12000 -12.1  10.2  290  35 18   6.6   3.6 | -12.2  10.0  290  34 17   7.6   4.2
 11750 -11.6  11.1  290  34 17   5.8   3.2 | -11.8  10.8  290  34 17   6.0   3.3
 11500 -11.2  11.8  290  32 17   6.8   3.7 | -11.3  11.7  290  33 17   8.0   4.4
 11250 -10.7  12.7  285  30 16   7.4   4.0 | -10.6  12.9  290  32 17   9.1   5.0
 11000 -10.1  13.8  285  28 14   7.3   4.0 |  -9.9  14.2  290  32 16   8.7   4.8
 10750  -9.6  14.7  285  26 13   8.0   4.4 |  -9.3  15.3  285  31 16   7.8   4.3
 10500  -9.0  15.8  280  23 12   7.5   4.1 |  -8.8  16.2  285  30 16   7.7   4.2
 10250  -8.5  16.7  280  21 11   6.9   3.8 |  -8.2  17.2  285  29 15   8.3   4.5
 10000  -8.0  17.6  280  19 10   6.7   3.7 |  -7.6  18.3  285  27 14   8.0   4.4
  9750  -7.5  18.5  275  17  9   8.2   4.5 |  -7.0  19.4  285  26 13   8.6   4.7
  9500  -6.3  20.7  270  13  7   6.4   3.5 |  -5.8  21.6  280  23 12   7.2   4.0
  9250  -5.8  21.6  270  11  6   7.2   4.0 |  -5.3  22.5  280  22 11   7.9   4.3
  9000  -5.3  22.5  260   9  5   5.6   3.1 |  -4.7  23.5  275  20 10   6.2   3.4
  8750  -4.9  23.2  250   8  4   5.5   3.0 |  -4.3  24.3  270  18  9   5.9   3.3
  8500  -4.4  24.1  240   7  4   6.8   3.7 |  -3.8  25.2  270  16  8   7.7   4.2
  8250  -4.0  24.8  230   6  3   6.6   3.6 |  -3.3  26.1  265  14  7   6.5   3.6
  8000  -3.5  25.7  215   5  3   7.2   4.0 |  -2.9  26.8  255  12  6   3.7   2.0
  7750  -2.9  26.8  205   4  2   8.8   4.8 |  -3.0  26.6  245  10  5  -7.1  -3.9
  7500  -2.2  28.0  185   3  2  10.7   5.9 |  -4.1  24.6  235   7  4 -20.7 -11.4
  7250  -1.5  29.3  160   3  2   7.6   4.2 |  -5.2  22.6  205   5  2   2.3   1.3
  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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