Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 211138
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0437 MST Sunday, December 21, 2014

This forecast is for Sunday, December 21, 2014:

If the trigger temperature of 42.2 F/5.7 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 304 ft/min (1.5 m/s)
   Maximum height of thermals.................. 13192 ft MSL (6434 ft AGL)

Forecast maximum temperature................... 49.0 F/9.9 C
Time of trigger temperature.................... 1045 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11073 ft MSL (4315 ft AGL)
Thermal soaring outlook for Monday 12/22....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:14:04 / 16:40:23 MST
Total possible sunshine........... 9 hr 26 min 19 sec (566 min 19 sec)
Altitude of sun at 11:57:14 MST... 27.68 degrees

Upper air data from numerical model forecast valid on 12/21/2014 at 0500 MST

Freezing level.................. 7163 ft MSL (405 ft AGL)
Additional freezing level....... 8215 ft MSL (1457 ft AGL)
Convective condensation level... 16192 ft MSL (9434 ft AGL)
Lifted condensation level....... 14571 ft MSL (7813 ft AGL)
Lifted index.................... +3.0
K index......................... +6.4

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  -57.7 -71.9   310   22   11  -0.0  -0.0      M     M       M      M    M
 45000  -57.7 -71.9   315   30   16  -0.0  -0.0      M     M       M      M    M
 40000  -57.1 -70.8   325   51   26   0.4   0.2      M     M       M      M    M
 38000  -56.6 -69.9   330   57   29   1.8   1.0      M     M       M      M    M
 36000  -55.5 -67.9   335   60   31   1.8   1.0      M     M       M      M    M
 34000  -54.4 -65.9   345   64   33   2.7   1.5      M     M       M      M    M
 32000  -51.3 -60.3   345   75   38   5.4   3.0      M     M       M      M    M
 30000  -48.0 -54.4   345   86   44   6.4   3.5      M     M       M      M    M
 29000  -45.2 -49.4   345   75   39   7.7   4.2   21.0  69.8     8.9      M    M
 28000  -42.9 -45.2   340   66   34   7.7   4.2   20.2  68.4     8.4      M    M
 27000  -40.6 -41.1   340   57   30   7.6   4.2   19.6  67.2     8.0      M    M
 26000  -38.0 -36.4   335   50   26   9.0   4.9   19.1  66.4     7.8      M    M
 25000  -35.3 -31.5   330   43   22   9.0   4.9   18.8  65.9     7.6      M    M
 24000  -32.6 -26.7   320   37   19   9.1   5.0   18.6  65.5     7.5      M    M
 23000  -30.2 -22.4   315   36   18   7.7   4.2   18.0  64.4     7.1      M    M
 22000  -27.9 -18.2   315   37   19   7.7   4.2   17.2  63.0     6.5      M    M
 21000  -25.6 -14.1   315   38   20   7.7   4.2   16.6  61.8     6.0      M    M
 20000  -23.4 -10.1   315   38   19   7.5   4.1   15.7  60.3     5.3      M    M
 19500  -22.3  -8.1   315   37   19   7.5   4.1   15.3  59.6     5.0      M    M
 19000  -21.1  -6.0   315   37   19   7.5   4.1   15.0  58.9     4.7      M    M
 18500  -20.0  -4.0   315   37   19   7.4   4.1   14.6  58.3     4.4      M    M
 18000  -18.9  -2.0   315   37   19   8.1   4.4   14.3  57.7     4.1      M    M
 17500  -17.7   0.1   315   37   19   8.0   4.4   14.0  57.2     3.9      M    M
 17000  -16.5   2.3   315   37   19   7.9   4.3   13.7  56.7     3.7      M    M
 16500  -15.3   4.5   315   36   18   7.8   4.3   13.4  56.1     3.4      M    M
 16000  -14.2   6.4   315   35   18   7.6   4.1   13.1  55.5     3.1      M    M
 15500  -13.1   8.4   320   34   17   6.6   3.6   12.6  54.7     2.7      M    M
 15000  -12.2  10.0   320   32   17   6.8   3.7   12.1  53.7     2.2      M    M
 14500  -10.8  12.6   325   31   16   5.7   3.1   11.1  52.1     1.4      M    M
 14000  -10.0  14.0   330   30   15   5.8   3.2   10.5  50.9     0.8      M    M
 13500   -9.1  15.6   330   28   15   6.4   3.5    9.9  49.8     0.2      M    M
 13000   -8.1  17.4   330   27   14   6.3   3.5    9.4  48.9    -0.3    479  2.4
 12500   -7.3  18.9   330   26   13   5.7   3.1    8.8  47.8    -0.9    438  2.2
 12000   -6.5  20.3   325   25   13   4.7   2.6    8.1  46.5    -1.6    400  2.0
 11750   -6.2  20.8   325   24   12   4.6   2.5    7.6  45.8    -2.0    383  1.9
 11500   -5.8  21.6   325   23   12   4.4   2.4    7.2  45.0    -2.4    366  1.9
 11250   -5.5  22.1   320   22   11   4.6   2.5    6.8  44.3    -2.8    349  1.8
 11000   -5.2  22.6   320   21   11   3.1   1.7    6.4  43.5    -3.2    332  1.7
 10750   -5.0  23.0   320   20   10   3.4   1.9    5.8  42.5    -3.8    319  1.6
 10500   -4.7  23.5   315   19   10   5.1   2.8    5.4  41.8    -4.2    302  1.5
 10250   -4.4  24.1   315   18    9   3.8   2.1    5.0  41.1    -4.6    284  1.4
 10000   -4.0  24.8   315   17    9   7.3   4.0    4.6  40.4    -5.0    267  1.4
  9750   -3.3  26.1   310   16    8   8.6   4.7    4.6  40.3    -5.1    239  1.2
  9500   -2.8  27.0   310   14    7   6.3   3.5    4.4  39.9    -5.3    217  1.1
  9250   -2.3  27.9   310   13    7   6.5   3.6    4.1  39.4    -5.6    195  1.0
  9000   -1.8  28.8   305   12    6   8.0   4.4    3.9  39.0    -5.8    172  0.9
  8750   -1.2  29.8   305   11    6   8.7   4.8    3.9  38.9    -5.9    145  0.7
  8500   -0.6  30.9   305   11    5   7.5   4.1    3.7  38.7    -6.1    120  0.6
  8250   -0.0  32.0   300   10    5   7.8   4.3    3.6  38.4    -6.2     96  0.5
  8000    0.4  32.7   300   10    5   2.4   1.3    3.3  37.9    -6.6     75  0.4
  7750    0.4  32.7   295   10    5  -0.9  -0.5    2.5  36.5    -7.3     69  0.4
  7500    0.5  32.9   295    9    5   5.5   3.0    1.9  35.4    -8.0     58  0.3
  7250    0.7  33.3   285    8    4  -7.7  -4.3    1.4  34.5    -8.5     45  0.2
  7000   -1.2  29.8   285    7    4 -42.8 -23.5   -0.8  30.6   -10.7     95  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           12/21/2014 at 0800 MST          |       12/21/2014 at 1100 MST
                                           |
K index... +15.5  LI... +1.4               | K index... +12.8  LI... +2.0
CAPE... 0.0  CIN... -0.5                   | 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 -56.8 -70.2  325  26 13  -0.2  -0.1 | -57.4 -71.3  335  16  8   0.2   0.1
 45000 -57.1 -70.8  325  35 18  -0.2  -0.1 | -57.1 -70.8  340  22 11   0.2   0.1
 40000 -57.1 -70.8  325  51 26   0.0   0.0 | -56.3 -69.3  330  51 26   0.6   0.3
 38000 -56.5 -69.7  325  57 29   3.0   1.6 | -55.8 -68.4  330  62 32   1.3   0.7
 36000 -54.7 -66.5  335  62 32   3.0   1.7 | -55.0 -67.0  335  70 36   1.3   0.7
 34000 -52.9 -63.2  340  68 35   3.2   1.8 | -54.2 -65.6  340  79 41   2.8   1.5
 32000 -50.7 -59.3  335  66 34   3.6   2.0 | -51.3 -60.3  335  81 42   4.9   2.7
 30000 -48.6 -55.5  330  65 33   6.3   3.5 | -48.3 -54.9  330  84 43   7.9   4.3
 29000 -45.8 -50.4  330  62 32   9.2   5.0 | -44.7 -48.5  330  81 42   9.5   5.2
 28000 -43.1 -45.6  325  59 30   9.2   5.1 | -41.8 -43.2  325  79 41   9.5   5.2
 27000 -39.6 -39.3  320  56 29   9.2   5.1 | -39.0 -38.2  325  77 40   9.4   5.2
 26000 -37.0 -34.6  320  53 27   8.6   4.7 | -36.4 -33.5  325  72 37   8.6   4.7
 25000 -34.4 -29.9  315  50 26   8.7   4.8 | -33.8 -28.8  325  67 35   8.6   4.7
 24000 -31.8 -25.2  315  47 24   8.8   4.8 | -31.2 -24.2  320  62 32   8.7   4.8
 23000 -29.5 -21.1  315  42 22   7.6   4.1 | -28.8 -19.8  320  55 28   8.2   4.5
 22000 -27.2 -17.0  310  38 19   7.6   4.2 | -26.3 -15.3  320  48 25   8.2   4.5
 21000 -25.0 -13.0  310  33 17   7.4   4.1 | -23.9 -11.0  320  42 21   8.3   4.6
 20000 -22.9  -9.2  305  29 15   6.8   3.8 | -21.3  -6.3  320  39 20   8.7   4.8
 19500 -21.9  -7.4  305  27 14   6.9   3.8 | -20.0  -4.0  320  37 19   8.7   4.8
 19000 -20.9  -5.6  305  25 13   6.9   3.8 | -18.7  -1.7  320  36 19   8.7   4.8
 18500 -19.8  -3.6  300  23 12   6.9   3.8 | -17.4   0.7  320  35 18   8.6   4.7
 18000 -18.8  -1.8  305  22 11   7.4   4.0 | -16.2   2.8  320  33 17   7.7   4.2
 17500 -17.7   0.1  305  22 11   7.3   4.0 | -15.0   5.0  320  31 16   7.8   4.3
 17000 -16.6   2.1  305  21 11   7.7   4.2 | -13.8   7.2  320  30 15   8.3   4.5
 16500 -15.4   4.3  310  21 11   7.8   4.3 | -12.6   9.3  320  29 15   8.4   4.6
 16000 -14.3   6.3  310  20 11   7.9   4.3 | -11.3  11.7  320  29 15   8.1   4.4
 15500 -13.1   8.4  315  20 11   8.1   4.4 | -10.2  13.6  320  29 15   7.3   4.0
 15000 -11.9  10.6  320  21 11   8.1   4.4 |  -9.2  15.4  320  29 15   7.3   4.0
 14500 -10.7  12.7  320  21 11   7.8   4.3 |  -8.1  17.4  320  29 15   7.0   3.8
 14000  -9.5  14.9  325  22 11   8.0   4.4 |  -7.1  19.2  320  29 15   7.1   3.9
 13500  -8.5  16.7  330  22 12   6.2   3.4 |  -6.1  21.0  320  30 15   6.4   3.5
 13000  -7.5  18.5  330  23 12   6.2   3.4 |  -5.1  22.8  320  30 15   6.4   3.5
 12500  -6.6  20.1  330  24 12   6.1   3.3 |  -4.2  24.4  320  30 16   7.0   3.8
 12000  -5.8  21.6  330  24 12   4.9   2.7 |  -3.2  26.2  320  31 16   4.4   2.4
 11750  -5.4  22.3  330  24 13   4.3   2.4 |  -3.0  26.6  320  32 16   3.6   2.0
 11500  -5.1  22.8  330  25 13   4.8   2.6 |  -2.6  27.3  320  32 17   4.6   2.5
 11250  -4.7  23.5  330  25 13   4.9   2.7 |  -2.3  27.9  320  32 17   5.1   2.8
 11000  -4.4  24.1  330  24 13   4.6   2.5 |  -1.9  28.6  315  32 17   4.1   2.2
 10750  -4.1  24.6  330  24 13   4.0   2.2 |  -1.7  28.9  315  33 17   2.3   1.2
 10500  -3.8  25.2  330  24 12   4.4   2.4 |  -1.3  29.7  310  31 16   3.2   1.7
 10250  -3.1  26.4  325  22 11   4.7   2.6 |  -1.1  30.0  305  30 15   3.5   1.9
 10000  -2.7  27.1  320  21 11   4.3   2.4 |  -0.8  30.6  305  29 15   1.9   1.0
  9750  -2.4  27.7  320  20 10   4.8   2.6 |  -0.8  30.6  300  27 14   2.9   1.6
  9500  -2.0  28.4  315  19 10   5.6   3.1 |  -0.4  31.3  295  25 13   5.3   2.9
  9250  -1.6  29.1  310  17  9   5.2   2.9 |  -0.1  31.8  290  23 12   4.7   2.6
  9000  -1.2  29.8  305  16  8   6.0   3.3 |   0.3  32.5  285  22 11   4.7   2.6
  8750  -0.7  30.7  305  15  8   6.0   3.3 |   0.7  33.3  280  20 10   6.1   3.4
  8500  -0.3  31.5  300  14  7   6.0   3.3 |   1.2  34.2  275  18  9   7.4   4.1
  8250   0.1  32.2  295  13  7   4.4   2.4 |   1.7  35.1  270  16  8   7.2   4.0
  8000   0.3  32.5  290  12  6   0.4   0.2 |   2.2  36.0  260  14  7   4.2   2.3
  7750  -0.0  32.0  285  11  5 -12.7  -7.0 |   2.4  36.3  250  12  6   5.5   3.0
  7500  -1.8  28.8  285   8  4 -31.2 -17.1 |   3.1  37.6  240   9  5  14.8   8.1
  7250  -3.5  25.7  285   6  3   0.9   0.5 |   3.9  39.0  225   7  4  -3.8  -2.1
  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

           12/21/2014 at 1400 MST          |       12/21/2014 at 1700 MST
                                           |
K index... +17.8  LI... +0.8               | K index... +13.6  LI... +1.1
CAPE... 0.0  CIN... -0.3                   | 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 -57.7 -71.9  340  15  8   0.2   0.1 | -58.4 -73.1  340  18  9   1.4   0.7
 45000 -57.5 -71.5  335  22 11   0.1   0.1 | -56.4 -69.5  315  27 14   1.5   0.8
 40000 -56.1 -69.0  325  41 21   1.0   0.5 | -56.5 -69.7  320  46 24  -0.2  -0.1
 38000 -55.6 -68.1  330  52 27   0.6   0.3 | -56.3 -69.3  325  56 29   1.2   0.7
 36000 -55.2 -67.4  330  74 38   0.6   0.3 | -55.6 -68.1  330  67 34   1.2   0.7
 34000 -54.7 -66.5  335  92 47   4.9   2.7 | -54.7 -66.5  335  77 40   5.7   3.1
 32000 -50.9 -59.6  330  86 44   6.4   3.5 | -50.5 -58.9  330  75 39   7.1   3.9
 30000 -46.9 -52.4  320  81 42   8.9   4.9 | -46.1 -51.0  325  74 38   9.6   5.3
 29000 -44.2 -47.6  320  77 39   9.1   5.0 | -43.2 -45.8  325  75 38   9.6   5.3
 28000 -41.5 -42.7  315  72 37   9.1   5.0 | -40.4 -40.7  320  75 39   9.6   5.3
 27000 -38.8 -37.8  315  67 35   9.1   5.0 | -37.5 -35.5  320  76 39   9.8   5.4
 26000 -36.1 -33.0  315  65 34   8.8   4.8 | -35.0 -31.0  325  76 39   7.7   4.2
 25000 -33.5 -28.3  315  65 33   8.8   4.9 | -32.7 -26.9  325  75 39   7.7   4.2
 24000 -30.9 -23.6  315  64 33   8.9   4.9 | -29.9 -21.8  330  75 38   7.7   4.2
 23000 -27.8 -18.0  315  60 31   8.0   4.4 | -27.8 -18.0  330  68 35   6.9   3.8
 22000 -25.4 -13.7  315  55 28   8.0   4.4 | -25.8 -14.4  325  61 31   6.9   3.8
 21000 -23.1  -9.6  315  50 26   7.8   4.3 | -23.7 -10.7  325  53 27   7.4   4.1
 20000 -20.8  -5.4  310  42 22   7.6   4.2 | -21.3  -6.3  325  54 28   8.2   4.5
 19500 -19.7  -3.5  305  38 20   7.6   4.2 | -20.1  -4.2  325  55 28   8.2   4.5
 19000 -18.6  -1.5  305  34 18   7.6   4.2 | -18.9  -2.0  325  56 29   8.2   4.5
 18500 -17.4   0.7  300  31 16   7.6   4.2 | -17.7   0.1  325  57 29   8.3   4.5
 18000 -16.4   2.5  300  30 15   7.3   4.0 | -16.4   2.5  325  56 29   8.9   4.9
 17500 -15.3   4.5  305  30 15   7.3   4.0 | -15.1   4.8  325  54 28   8.9   4.9
 17000 -14.1   6.6  310  30 16   8.5   4.7 | -13.8   7.2  320  53 27   8.8   4.8
 16500 -12.8   9.0  315  31 16   8.7   4.8 | -12.4   9.7  320  56 29   8.8   4.8
 16000 -11.5  11.3  315  32 16   9.0   4.9 | -11.1  12.0  320  59 30   8.5   4.7
 15500 -10.1  13.8  320  34 17   9.4   5.2 |  -9.9  14.2  325  61 31   8.0   4.4
 15000  -8.7  16.3  320  36 19   9.4   5.2 |  -8.7  16.3  325  63 32   8.0   4.4
 14500  -7.4  18.7  325  38 19   8.2   4.5 |  -7.6  18.3  325  64 33   7.4   4.0
 14000  -6.2  20.8  325  39 20   8.4   4.6 |  -6.5  20.3  325  64 33   7.4   4.1
 13500  -5.0  23.0  325  41 21   7.2   4.0 |  -5.4  22.3  325  64 33   7.3   4.0
 13000  -3.9  25.0  325  44 22   7.3   4.0 |  -4.3  24.3  325  62 32   7.3   4.0
 12500  -2.9  26.8  325  46 24   7.7   4.2 |  -3.2  26.2  325  61 31   8.6   4.7
 12000  -2.0  28.4  325  46 24   3.9   2.2 |  -2.1  28.2  320  58 30   5.8   3.2
 11750  -1.7  28.9  325  46 24   3.6   2.0 |  -1.7  28.9  320  57 29   5.8   3.2
 11500  -1.4  29.5  325  46 24   3.4   1.9 |  -1.2  29.8  320  55 28   6.5   3.6
 11250  -1.2  29.8  320  45 23   3.5   1.9 |  -0.7  30.7  320  54 28   7.3   4.0
 11000  -1.0  30.2  320  44 23   2.6   1.4 |  -0.2  31.6  315  53 27   6.1   3.4
 10750  -0.9  30.4  315  43 22   1.5   0.8 |   0.2  32.4  315  52 27   4.8   2.6
 10500  -0.7  30.7  315  42 21   3.5   1.9 |   0.5  32.9  315  50 26   5.4   3.0
 10250  -0.4  31.3  310  39 20   4.8   2.6 |   0.9  33.6  310  49 25   5.8   3.2
 10000  -0.1  31.8  310  37 19   4.5   2.4 |   1.4  34.5  310  47 24   5.8   3.2
  9750   0.3  32.5  305  35 18   4.4   2.4 |   2.1  35.8  305  44 23   2.6   1.4
  9500   1.1  34.0  300  30 16   7.2   4.0 |   2.2  36.0  305  42 22   1.2   0.7
  9250   1.6  34.9  300  28 14   7.0   3.8 |   2.2  36.0  300  40 21   0.7   0.4
  9000   2.1  35.8  295  25 13   6.9   3.8 |   2.3  36.1  295  38 19   4.2   2.3
  8750   2.7  36.9  295  23 12   8.3   4.6 |   2.8  37.0  295  35 18   6.0   3.3
  8500   3.3  37.9  295  21 11   9.5   5.2 |   3.1  37.6  295  32 16   3.6   2.0
  8250   4.0  39.2  295  19 10   9.5   5.2 |   3.4  38.1  290  29 15   4.4   2.4
  8000   4.7  40.5  290  17  9   8.4   4.6 |   3.7  38.7  285  26 13   3.7   2.0
  7750   5.3  41.5  290  15  8   7.8   4.3 |   3.8  38.8  285  22 11  -1.3  -0.7
  7500   5.9  42.6  285  11  6  10.4   5.7 |   3.4  38.1  285  16  8  -8.1  -4.4
  7250   6.5  43.7  280   8  4   4.7   2.6 |   3.0  37.4  280  10  5   3.6   2.0
  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
________________________________________________________________________________

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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