Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 291333
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0733 MDT Sunday, March 29, 2015

This forecast is for Sunday, March 29, 2015:

If the trigger temperature of 51.6 F/10.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 606 ft/min (3.1 m/s)
   Maximum height of thermals.................. 14250 ft MSL (7492 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... 1130 MDT
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................. 11967 ft MSL (5210 ft AGL)
Thermal soaring outlook for Monday 03/30....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:48:36 / 19:18:35 MDT
Total possible sunshine........... 12 hr 29 min 59 sec (749 min 59 sec)
Altitude of sun at 13:03:45 MDT... 54.53 degrees

Upper air data from numerical model forecast valid on 03/29/2015 at 0600 MDT

Freezing level.................. 10851 ft MSL (4093 ft AGL)
Convective condensation level... 16796 ft MSL (10038 ft AGL)
Lifted condensation level....... 15669 ft MSL (8911 ft AGL)
Lifted index.................... +0.0
K index......................... +10.1

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  -61.4 -78.5   270   40   20   4.5   2.5      M     M       M      M    M
 45000  -54.3 -65.7   265   51   26   6.5   3.6      M     M       M      M    M
 40000  -44.1 -47.4   265   61   31   6.8   3.7      M     M       M      M    M
 38000  -44.6 -48.3   265   62   32  -2.6  -1.4      M     M       M      M    M
 36000  -46.1 -51.0   270   62   32  -2.6  -1.4      M     M       M      M    M
 34000  -46.9 -52.4   270   62   32   1.5   0.8      M     M       M      M    M
 32000  -45.9 -50.6   270   59   30   1.6   0.9      M     M       M      M    M
 30000  -43.9 -47.0   275   56   29   7.6   4.2   26.2  79.2     8.2      M    M
 29000  -41.0 -41.8   275   54   28   7.7   4.2   25.2  77.3     7.5      M    M
 28000  -38.7 -37.7   275   53   27   7.7   4.2   24.5  76.0     7.0      M    M
 27000  -36.4 -33.5   275   52   27   7.8   4.3   23.8  74.8     6.5      M    M
 26000  -34.0 -29.2   275   52   27   7.8   4.3   22.9  73.3     5.9      M    M
 25000  -31.7 -25.1   275   51   26   7.8   4.3   22.2  72.0     5.4      M    M
 24000  -29.4 -20.9   280   50   26   7.9   4.3   21.6  70.9     4.9      M    M
 23000  -27.1 -16.8   280   47   24   7.9   4.3   20.8  69.5     4.3      M    M
 22000  -24.7 -12.5   280   45   23   7.9   4.3   20.2  68.4     3.8      M    M
 21000  -22.2  -8.0   280   42   22   9.3   5.1   19.8  67.6     3.5      M    M
 20000  -19.4  -2.9   280   40   21   9.3   5.1   19.6  67.2     3.3      M    M
 19500  -18.1  -0.6   275   39   20   9.3   5.1   19.5  67.1     3.3      M    M
 19000  -16.7   1.9   275   38   20   9.4   5.2   19.5  67.0     3.3      M    M
 18500  -15.5   4.1   280   39   20   7.1   3.9   19.2  66.6     3.0      M    M
 18000  -14.4   6.1   285   40   21   7.3   4.0   18.8  65.8     2.7      M    M
 17500  -13.3   8.1   285   42   22   8.0   4.4   18.4  65.1     2.3      M    M
 17000  -12.1  10.2   290   43   22   8.3   4.6   18.2  64.7     2.1      M    M
 16500  -10.8  12.6   290   44   23   8.3   4.5   17.9  64.3     1.9      M    M
 16000   -9.6  14.7   295   44   23   7.8   4.3   17.6  63.7     1.6      M    M
 15500   -8.5  16.7   295   44   22   8.0   4.4   17.3  63.2     1.3      M    M
 15000   -7.4  18.7   300   43   22   6.2   3.4   16.9  62.4     0.9      M    M
 14500   -6.0  21.2   300   39   20   6.2   3.4   16.0  60.9     0.2      M    M
 14000   -5.2  22.6   305   37   19   5.7   3.1   15.4  59.7    -0.4    576  2.9
 13500   -4.3  24.3   310   34   18   5.8   3.2   14.8  58.6    -1.1    536  2.7
 13000   -3.5  25.7   315   32   17   5.4   3.0   14.1  57.4    -1.7    497  2.5
 12500   -2.7  27.1   320   31   16   5.4   3.0   13.4  56.2    -2.4    458  2.3
 12000   -1.9  28.6   325   31   16   5.2   2.9   12.7  54.9    -3.1    420  2.1
 11750   -1.5  29.3   330   30   16   5.4   3.0   12.4  54.3    -3.4    401  2.0
 11500   -1.1  30.0   330   30   15   4.8   2.7   12.0  53.6    -3.8    382  1.9
 11250   -0.8  30.6   335   30   15   7.1   3.9   11.7  53.0    -4.1    363  1.8
 11000   -0.1  31.8   340   29   15   7.4   4.1   11.6  52.8    -4.3    338  1.7
 10750    0.3  32.5   340   29   15   5.4   3.0   11.3  52.3    -4.6    317  1.6
 10500    0.7  33.3   345   29   15   5.9   3.3   11.0  51.7    -4.9    297  1.5
 10250    1.1  34.0   350   29   15   6.4   3.5   10.7  51.2    -5.2    277  1.4
 10000    1.6  34.9   350   29   15   7.0   3.8   10.4  50.8    -5.4    254  1.3
  9750    2.1  35.8   355   30   15   7.0   3.8   10.2  50.4    -5.7    232  1.2
  9500    2.7  36.9   360   30   16   6.7   3.7   10.0  50.0    -5.9    209  1.1
  9250    3.1  37.6   005   31   16   5.3   2.9    9.7  49.5    -6.2    188  1.0
  9000    3.5  38.3   005   33   17   4.4   2.4    9.3  48.8    -6.6    170  0.9
  8750    3.8  38.8   010   35   18   4.9   2.7    9.0  48.1    -7.0    152  0.8
  8500    4.2  39.6   010   37   19   4.2   2.3    8.6  47.4    -7.4    134  0.7
  8250    4.4  39.9   015   36   18   3.4   1.9    8.1  46.6    -7.9    119  0.6
  8000    4.6  40.3   015   33   17   2.2   1.2    7.6  45.7    -8.4    106  0.5
  7750    4.8  40.6   015   31   16   6.3   3.5    7.1  44.8    -9.0     92  0.5
  7500    5.3  41.5   015   29   15   1.0   0.5    6.9  44.4    -9.2     71  0.4
  7250    4.8  40.6   010   24   12  -8.9  -4.9    6.1  43.0   -10.0     78  0.4
  7000    4.4  39.9   010   19   10  -1.1  -0.6    5.3  41.6   -10.9     84  0.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           03/29/2015 at 0900 MDT          |       03/29/2015 at 1200 MDT
                                           |
K index... -5.0  LI... +275.9              | K index... -12.0  LI... +276.7
CAPE... 0.0  CIN... -0.3                   | 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 -60.7 -77.3  275  41 21   4.7   2.6 | -60.5 -76.9  275  45 23   3.8   2.1
 45000 -53.5 -64.3  285  51 26   5.3   2.9 | -54.6 -66.3  280  59 30   4.9   2.7
 40000 -45.1 -49.2  275  64 33   5.3   2.9 | -46.9 -52.4  280  66 34   4.9   2.7
 38000 -45.8 -50.4  275  63 33  -2.9  -1.6 | -47.3 -53.1  280  65 33  -2.3  -1.3
 36000 -47.5 -53.5  275  61 31  -2.9  -1.6 | -48.7 -55.7  285  62 32  -2.3  -1.3
 34000 -48.2 -54.8  275  59 30   2.7   1.5 | -49.0 -56.2  285  57 29   3.2   1.7
 32000 -46.6 -51.9  275  58 30   2.8   1.5 | -47.1 -52.8  295  45 23   3.2   1.8
 30000 -44.1 -47.4  275  56 29   7.3   4.0 | -44.3 -47.7  300  37 19   7.5   4.1
 29000 -41.3 -42.3  280  54 28   7.4   4.0 | -42.0 -43.6  310  36 18   7.6   4.1
 28000 -39.1 -38.4  280  52 27   7.4   4.0 | -39.8 -39.6  315  35 18   7.5   4.1
 27000 -36.9 -34.4  285  49 25   7.8   4.3 | -37.5 -35.5  320  35 18   7.9   4.3
 26000 -34.6 -30.3  285  47 24   7.7   4.2 | -35.1 -31.2  315  35 18   7.9   4.3
 25000 -32.2 -26.0  285  45 23   7.7   4.2 | -32.2 -26.0  315  36 18   7.9   4.3
 24000 -29.9 -21.8  290  43 22   8.8   4.8 | -29.8 -21.6  315  36 19   8.0   4.4
 23000 -27.3 -17.1  290  42 22   8.7   4.8 | -27.4 -17.3  315  36 18   8.0   4.4
 22000 -24.7 -12.5  285  41 21   8.6   4.7 | -25.0 -13.0  315  36 18   8.0   4.4
 21000 -22.2  -8.0  290  41 21   8.0   4.4 | -22.6  -8.7  315  35 18   8.4   4.6
 20000 -19.8  -3.6  290  42 22   8.0   4.4 | -20.0  -4.0  315  34 17   8.4   4.6
 19500 -18.6  -1.5  295  43 22   8.0   4.4 | -18.8  -1.8  315  33 17   8.4   4.6
 19000 -17.4   0.7  295  44 23   8.0   4.4 | -17.5   0.5  315  33 17   8.4   4.6
 18500 -16.2   2.8  295  45 23   7.6   4.2 | -16.3   2.7  310  33 17   8.3   4.6
 18000 -15.0   5.0  300  45 23   7.7   4.2 | -15.0   5.0  310  33 17   8.3   4.6
 17500 -13.9   7.0  300  46 24   8.1   4.4 | -13.8   7.2  310  34 17   8.0   4.4
 17000 -12.7   9.1  300  46 24   8.3   4.5 | -12.6   9.3  310  33 17   8.0   4.4
 16500 -11.4  11.5  300  47 24   8.3   4.6 | -11.5  11.3  310  32 17   7.7   4.2
 16000 -10.2  13.6  300  46 24   8.5   4.7 | -10.3  13.5  310  32 16   7.5   4.1
 15500  -8.9  16.0  305  45 23   8.5   4.7 |  -9.2  15.4  310  31 16   7.5   4.1
 15000  -7.7  18.1  305  43 22   8.0   4.4 |  -8.1  17.4  310  30 15   7.4   4.1
 14500  -5.8  21.6  310  39 20   7.9   4.3 |  -7.0  19.4  310  29 15   7.5   4.1
 14000  -4.7  23.5  310  36 19   7.3   4.0 |  -6.0  21.2  310  28 14   6.4   3.5
 13500  -3.6  25.5  310  33 17   7.2   3.9 |  -5.0  23.0  310  27 14   6.5   3.5
 13000  -2.7  27.1  310  31 16   5.8   3.2 |  -4.0  24.8  310  26 14   6.8   3.7
 12500  -1.8  28.8  310  28 15   6.0   3.3 |  -3.0  26.6  315  25 13   6.9   3.8
 12000  -1.1  30.0  310  26 13   3.7   2.1 |  -2.1  28.2  315  24 12   6.9   3.8
 11750  -0.9  30.4  315  25 13   4.0   2.2 |  -1.5  29.3  315  22 12   7.3   4.0
 11500  -0.6  30.9  315  24 12   4.0   2.2 |  -1.0  30.2  315  21 11   7.5   4.1
 11250  -0.4  31.3  315  23 12   1.6   0.9 |  -0.4  31.3  310  20 10   6.4   3.5
 11000  -0.4  31.3  320  22 11  -0.2  -0.1 |  -0.1  31.8  310  19 10   4.0   2.2
 10750  -0.4  31.3  320  21 11   0.4   0.2 |   0.1  32.2  310  17  9   2.7   1.5
 10500  -0.4  31.3  325  20 10   0.3   0.2 |   0.3  32.5  305  16  8   2.9   1.6
 10250  -0.4  31.3  330  19 10   0.1   0.0 |   0.5  32.9  305  15  8   1.2   0.7
 10000  -0.5  31.1  340  20 11  -0.1  -0.1 |   0.4  32.7  310  14  7  -2.3  -1.2
  9750  -0.5  31.1  350  22 11  -0.9  -0.5 |   0.3  32.5  335  10  5   1.7   1.0
  9500  -0.5  31.1  355  24 12   0.1   0.1 |   0.4  32.7  355  10  5   5.8   3.2
  9250  -0.4  31.3  360  25 13   3.0   1.6 |   1.1  34.0  360  10  5   9.8   5.4
  9000  -0.2  31.6  005  26 13   3.4   1.8 |   1.7  35.1  005  10  5   9.0   4.9
  8750   0.1  32.2  005  27 14   4.5   2.5 |   2.5  36.5  005  10  5  10.5   5.8
  8500   0.6  33.1  010  27 14   8.0   4.4 |   3.3  37.9  010  10  5  10.7   5.9
  8250   1.2  34.2  010  25 13   9.5   5.2 |   4.1  39.4  010  10  5  10.8   5.9
  8000   1.9  35.4  010  23 12   8.6   4.7 |   4.9  40.8  010  10  5   9.8   5.4
  7750   2.5  36.5  005  21 11  11.2   6.1 |   5.7  42.3  010  10  5  15.2   8.3
  7500   3.4  38.1  005  20 10  10.1   5.5 |   7.3  45.1  015  10  5  27.8  15.3
  7250   3.9  39.0  005  18  9   6.0   3.3 |   9.0  48.2  015   9  5   8.3   4.5
  7000   4.5  40.1  005  16  8   9.3   5.1 |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/29/2015 at 1500 MDT          |       03/29/2015 at 1800 MDT
                                           |
K index... -0.6  LI... +274.3              | K index... +9.8  LI... +273.1
CAPE... +7.3  CIN... -31.6                 | CAPE... +172.5  CIN... -15.1
                                           |
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 -59.9 -75.8  275  47 24   3.7   2.0 | -59.3 -74.7  275  47 24   3.4   1.9
 45000 -54.3 -65.7  280  56 29   3.9   2.1 | -54.5 -66.1  280  58 30   1.6   0.9
 40000 -48.3 -54.9  275  64 33   3.6   2.0 | -52.1 -61.8  275  64 33   1.6   0.9
 38000 -49.1 -56.4  275  62 32  -3.1  -1.7 | -52.3 -62.1  275  62 32  -1.3  -0.7
 36000 -50.9 -59.6  280  59 30  -3.1  -1.7 | -53.0 -63.4  280  57 29  -1.3  -0.7
 34000 -51.3 -60.3  285  53 27   4.6   2.5 | -52.7 -62.9  285  51 26   5.3   2.9
 32000 -48.5 -55.3  285  40 20   4.6   2.5 | -49.0 -56.2  285  42 22   5.5   3.0
 30000 -45.0 -49.0  295  31 16   8.3   4.5 | -44.9 -48.8  290  38 19   8.9   4.9
 29000 -42.5 -44.5  300  32 16   8.3   4.5 | -42.2 -44.0  295  38 19   8.9   4.9
 28000 -40.1 -40.2  310  33 17   8.3   4.5 | -39.6 -39.3  300  38 19   8.9   4.9
 27000 -36.9 -34.4  315  34 18   8.7   4.8 | -36.9 -34.4  305  38 20   8.6   4.7
 26000 -34.3 -29.7  320  35 18   8.7   4.8 | -34.4 -29.9  310  38 19   8.6   4.7
 25000 -31.7 -25.1  320  36 19   8.7   4.8 | -31.8 -25.2  310  37 19   8.6   4.7
 24000 -29.1 -20.4  325  37 19   8.8   4.8 | -29.2 -20.6  315  37 19   9.1   5.0
 23000 -26.4 -15.5  325  36 19   8.8   4.8 | -26.5 -15.7  315  35 18   9.0   5.0
 22000 -23.8 -10.8  325  35 18   8.7   4.8 | -23.7 -10.7  315  33 17   9.0   4.9
 21000 -21.3  -6.3  325  35 18   8.1   4.4 | -21.1  -6.0  315  32 16   8.3   4.5
 20000 -18.9  -2.0  325  34 18   8.1   4.4 | -18.6  -1.5  315  31 16   8.3   4.5
 19500 -17.7   0.1  325  34 18   8.1   4.4 | -17.4   0.7  315  30 16   8.3   4.5
 19000 -16.5   2.3  325  34 17   8.1   4.4 | -16.2   2.8  315  30 15   8.2   4.5
 18500 -15.3   4.5  320  34 17   7.9   4.4 | -15.0   5.0  315  29 15   7.5   4.1
 18000 -14.1   6.6  320  33 17   7.9   4.4 | -13.9   7.0  310  29 15   7.6   4.2
 17500 -12.9   8.8  320  32 17   8.1   4.4 | -12.8   9.0  310  28 14   7.1   3.9
 17000 -11.7  10.9  320  31 16   8.1   4.4 | -11.7  10.9  305  27 14   7.1   3.9
 16500 -10.5  13.1  320  29 15   7.8   4.3 | -10.7  12.7  295  27 14   7.3   4.0
 16000  -9.4  15.1  315  29 15   7.2   3.9 |  -9.0  15.8  290  26 13   8.0   4.4
 15500  -8.4  16.9  315  29 15   7.1   3.9 |  -7.9  17.8  285  26 13   8.5   4.7
 15000  -7.4  18.7  310  28 14   6.1   3.3 |  -6.6  20.1  280  25 13   8.8   4.8
 14500  -6.5  20.3  305  27 14   6.2   3.4 |  -5.3  22.5  275  24 12   9.0   4.9
 14000  -5.6  21.9  295  25 13   7.3   4.0 |  -4.0  24.8  275  23 12   9.2   5.0
 13500  -4.1  24.6  285  22 11   7.7   4.2 |  -2.7  27.1  275  22 11   9.1   5.0
 13000  -3.0  26.6  275  20 10   8.1   4.4 |  -1.4  29.5  270  20 10   8.4   4.6
 12500  -1.8  28.8  270  18  9   7.9   4.3 |  -0.1  31.8  265  17  9   6.5   3.5
 12000  -1.0  30.2  265  15  8   3.8   2.1 |   0.6  33.1  250  15  8   6.2   3.4
 11750  -0.7  30.7  260  14  7   4.3   2.4 |   1.1  34.0  245  14  7   5.8   3.2
 11500  -0.4  31.3  255  12  6   3.8   2.1 |   1.5  34.7  235  13  7   6.0   3.3
 11250  -0.2  31.6  250  11  5   1.1   0.6 |   1.9  35.4  230  12  6   2.3   1.2
 11000  -0.2  31.6  235   8  4   2.5   1.4 |   1.9  35.4  225  11  6   0.3   0.2
 10750   0.2  32.4  220   6  3   4.8   2.6 |   2.0  35.6  215  11  6   1.6   0.9
 10500   0.5  32.9  195   5  2   5.0   2.8 |   2.1  35.8  205  10  5   1.5   0.8
 10250   1.0  33.8  170   5  3   8.4   4.6 |   2.3  36.1  200  10  5   3.8   2.1
 10000   1.7  35.1  170   5  3   9.7   5.3 |   2.7  36.9  195  10  5   5.4   3.0
  9750   2.4  36.3  165   5  3   9.1   5.0 |   3.1  37.6  190  11  5   4.9   2.7
  9500   3.1  37.6  160   5  3   9.4   5.2 |   3.4  38.1  180  11  6   5.8   3.2
  9250   3.8  38.8  160   5  3   9.7   5.3 |   4.0  39.2  175  12  6   8.0   4.4
  9000   4.5  40.1  160   5  3   9.8   5.4 |   4.6  40.3  175  12  6   8.7   4.8
  8750   5.3  41.5  160   5  3  10.4   5.7 |   5.3  41.5  175  12  6   9.4   5.2
  8500   6.1  43.0  155   5  3  10.7   5.9 |   6.0  42.8  170  12  6  10.2   5.6
  8250   6.9  44.4  155   6  3  10.6   5.8 |   6.7  44.1  170  12  6   9.9   5.4
  8000   7.7  45.9  155   6  3  10.1   5.5 |   7.5  45.5  170  12  6  10.1   5.5
  7750   8.4  47.1  155   6  3  12.3   6.7 |   8.2  46.8  170  12  6   9.5   5.2
  7500   9.4  48.9  150   6  3  13.0   7.1 |   8.9  48.0  170  12  6   8.0   4.4
  7250  10.3  50.5  150   6  3  10.8   5.9 |   9.4  48.9  165  11  6   7.5   4.1
  7000  11.1  52.0  145   6  3  12.7   6.9 |  10.0  50.0  165  11  6   7.9   4.3
  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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