Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 171035
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0434 MDT Thursday, April 17, 2014

This forecast is for Thursday, April 17, 2014:

If the trigger temperature of 43.4 F/6.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1082 ft/min (5.5 m/s)
   Maximum height of thermals.................. 18618 ft MSL (11860 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 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................. 15562 ft MSL (8804 ft AGL)
Thermal soaring outlook for Friday 04/18....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Neutral
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 33886 ft MSL (27128 ft AGL)
Wave soaring outlook for Friday 04/18.......... Poor

Remarks...

Sunrise/Sunset.................... 06:19:36 / 19:37:13 MDT
Total possible sunshine........... 13 hr 17 min 37 sec (797 min 37 sec)
Altitude of sun at 12:58:34 MDT... 61.70 degrees

Upper air data from numerical model forecast valid on 04/17/2014 at 0600 MDT

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 13170 ft MSL (6412 ft AGL)
Lifted condensation level....... 14675 ft MSL (7917 ft AGL)
Lifted index.................... -1.4
K index......................... +5.6

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  -56.6 -69.9   305   29   15   1.2   0.6      M     M       M      M    M
 45000  -54.8 -66.6   305   33   17   1.4   0.8      M     M       M      M    M
 40000  -55.8 -68.4   315   40   21  -0.8  -0.4      M     M       M      M    M
 38000  -55.9 -68.6   320   45   23   0.8   0.5      M     M       M      M    M
 36000  -55.4 -67.7   325   54   28   0.9   0.5      M     M       M      M    M
 34000  -54.6 -66.3   330   64   33   4.4   2.4      M     M       M      M    M
 32000  -51.7 -61.1   335   62   32   4.8   2.7      M     M       M      M    M
 30000  -48.6 -55.5   335   60   31   8.3   4.6   21.2  70.1     6.4      M    M
 29000  -46.2 -51.2   335   58   30   8.0   4.4   20.4  68.6     5.9      M    M
 28000  -43.8 -46.8   335   55   29   8.0   4.4   19.7  67.4     5.4      M    M
 27000  -41.4 -42.5   335   53   27   8.0   4.4   19.1  66.4     5.0      M    M
 26000  -38.9 -38.0   330   49   25   8.5   4.7   18.5  65.4     4.6      M    M
 25000  -36.3 -33.3   330   45   23   8.5   4.7   18.1  64.5     4.3      M    M
 24000  -33.8 -28.8   325   42   21   8.7   4.8   17.7  63.9     4.0      M    M
 23000  -31.4 -24.5   325   39   20   7.5   4.1   16.9  62.5     3.4      M    M
 22000  -29.2 -20.6   325   37   19   7.5   4.1   16.1  61.0     2.8      M    M
 21000  -26.9 -16.4   320   34   18   7.2   4.0   15.4  59.7     2.2      M    M
 20000  -24.9 -12.8   320   33   17   6.8   3.7   14.3  57.7     1.3      M    M
 19500  -23.9 -11.0   320   33   17   6.8   3.7   13.7  56.7     0.8      M    M
 19000  -22.9  -9.2   320   33   17   6.8   3.7   13.3  55.9     0.4      M    M
 18500  -21.9  -7.4   325   32   17   6.8   3.8   12.8  55.0    -0.0   1080  5.5
 18000  -20.8  -5.4   325   31   16   7.1   3.9   12.3  54.2    -0.4   1034  5.3
 17500  -19.8  -3.6   325   30   15   7.1   3.9   11.9  53.4    -0.9    987  5.0
 17000  -18.8  -1.8   325   29   15   6.4   3.5   11.4  52.5    -1.3    942  4.8
 16500  -17.8  -0.0   325   27   14   6.4   3.5   10.8  51.4    -1.9    899  4.6
 16000  -16.4   2.5   330   26   13   6.6   3.6   10.0  50.0    -2.7    834  4.2
 15500  -15.4   4.3   330   24   12   6.4   3.5    9.5  49.0    -3.2    791  4.0
 15000  -14.4   6.1   330   22   12   8.5   4.7    9.1  48.3    -3.6    744  3.8
 14500  -13.1   8.4   325   21   11   8.6   4.7    8.9  47.9    -3.8    691  3.5
 14000  -11.8  10.8   325   19   10   8.7   4.8    8.7  47.6    -4.0    638  3.2
 13500  -10.5  13.1   320   18    9   8.7   4.8    8.5  47.3    -4.2    584  3.0
 13000   -9.2  15.4   320   16    8   8.7   4.8    8.4  47.0    -4.4    530  2.7
 12500   -7.9  17.8   315   15    8   8.7   4.8    8.2  46.7    -4.6    477  2.4
 12000   -6.6  20.1   310   14    7   8.1   4.4    8.0  46.5    -4.8    423  2.2
 11750   -6.1  21.0   305   14    7   6.9   3.8    7.8  46.1    -5.0    400  2.0
 11500   -5.6  21.9   300   14    7   7.5   4.1    7.6  45.7    -5.2    377  1.9
 11250   -5.1  22.8   295   13    7   6.3   3.5    7.4  45.4    -5.5    354  1.8
 11000   -4.7  23.5   290   13    7   4.1   2.2    7.1  44.7    -5.8    335  1.7
 10750   -4.4  24.1   285   12    6   4.3   2.3    6.6  43.9    -6.3    319  1.6
 10500   -4.1  24.6   280   12    6   5.2   2.8    6.2  43.2    -6.7    301  1.5
 10250   -3.7  25.3   270   12    6   4.2   2.3    5.9  42.5    -7.1    284  1.4
 10000   -3.5  25.7   265   12    6   1.8   1.0    5.3  41.6    -7.6    270  1.4
  9750   -3.4  25.9   255   12    6   1.2   0.6    4.7  40.4    -8.3    260  1.3
  9500   -3.3  26.1   250   12    6   1.9   1.0    4.0  39.3    -9.0    249  1.3
  9250   -3.2  26.2   240   12    6   1.3   0.7    3.4  38.2    -9.6    239  1.2
  9000   -3.1  26.4   235   12    6   1.1   0.6    2.8  37.0   -10.3    229  1.2
  8750   -3.1  26.4   225   13    6   0.4   0.2    2.1  35.8   -11.0    220  1.1
  8500   -3.1  26.4   215   14    7  -0.4  -0.2    1.3  34.4   -11.8    214  1.1
  8250   -3.1  26.4   210   15    8   1.1   0.6    0.6  33.1   -12.6    207  1.1
  8000   -3.0  26.6   205   14    7   1.8   1.0   -0.0  32.0   -13.2    196  1.0
  7750   -2.9  26.8   200   14    7   2.8   1.5   -0.6  30.9   -13.9    185  0.9
  7500   -2.7  27.1   195   13    7   2.8   1.5   -1.1  30.1   -14.4    171  0.9
  7250   -2.6  27.3   190   12    6   0.6   0.3   -1.4  29.5   -14.8    161  0.8
  7000   -2.5  27.5   190   10    5   1.0   0.5   -1.6  29.1   -15.0    152  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/17/2014 at 0900 MDT          |       04/17/2014 at 1200 MDT
                                           |
K index... +3.1  LI... +3.3                | K index... +3.5  LI... +3.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.9
                                           |
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  305  29 15   0.6   0.3 | -57.5 -71.5  300  28 14   0.1   0.0
 45000 -56.8 -70.2  315  37 19   0.9   0.5 | -57.4 -71.3  315  35 18   0.3   0.2
 40000 -59.1 -74.4  325  56 29  -1.6  -0.9 | -61.1 -78.0  330  56 29  -2.5  -1.4
 38000 -59.2 -74.6  335  66 34   2.5   1.4 | -60.5 -76.9  330  61 32   4.8   2.6
 36000 -57.7 -71.9  340  78 40   2.5   1.4 | -57.6 -71.7  335  64 33   4.8   2.6
 34000 -55.4 -67.7  345  90 46   8.5   4.7 | -54.4 -65.9  340  67 34   8.4   4.6
 32000 -50.6 -59.1  345  84 43   8.0   4.4 | -49.6 -57.3  335  65 34   8.1   4.4
 30000 -45.9 -50.6  340  78 40   6.7   3.6 | -44.8 -48.6  330  63 32   7.2   4.0
 29000 -43.9 -47.0  340  73 37   6.7   3.7 | -42.6 -44.7  330  61 31   7.3   4.0
 28000 -41.9 -43.4  340  68 35   6.8   3.7 | -39.9 -39.8  330  57 30   7.3   4.0
 27000 -39.9 -39.8  335  63 32   7.2   4.0 | -37.7 -35.9  330  55 28   7.8   4.3
 26000 -37.4 -35.3  335  57 29   8.2   4.5 | -35.3 -31.5  325  53 27   7.9   4.4
 25000 -35.0 -31.0  330  52 27   8.2   4.5 | -32.9 -27.2  325  51 26   7.9   4.4
 24000 -32.5 -26.5  325  46 24   8.3   4.5 | -30.6 -23.1  325  49 25   7.9   4.3
 23000 -29.9 -21.8  325  44 22   8.7   4.8 | -28.2 -18.8  325  46 24   7.8   4.3
 22000 -27.3 -17.1  325  41 21   8.7   4.8 | -25.9 -14.6  320  43 22   7.8   4.3
 21000 -24.7 -12.5  325  39 20   6.7   3.7 | -23.6 -10.5  320  41 21   6.2   3.4
 20000 -23.1  -9.6  325  36 19   5.4   3.0 | -21.8  -7.2  320  39 20   6.0   3.3
 19500 -22.3  -8.1  325  35 18   5.4   3.0 | -20.9  -5.6  320  38 19   6.0   3.3
 19000 -21.5  -6.7  325  34 17   5.4   3.0 | -20.1  -4.2  320  37 19   6.0   3.3
 18500 -20.7  -5.3  325  33 17   5.9   3.2 | -19.2  -2.6  320  36 18   5.8   3.2
 18000 -19.7  -3.5  325  31 16   6.5   3.6 | -18.3  -0.9  320  34 17   5.8   3.2
 17500 -18.8  -1.8  325  30 16   6.5   3.6 | -17.4   0.7  320  32 16   5.7   3.1
 17000 -17.8  -0.0  325  29 15   6.9   3.8 | -16.6   2.1  320  30 15   5.1   2.8
 16500 -16.7   1.9  325  28 14   6.9   3.8 | -15.9   3.4  320  27 14   5.0   2.7
 16000 -15.3   4.5  325  26 13   6.4   3.5 | -15.1   4.8  315  25 13   6.6   3.6
 15500 -14.3   6.3  325  25 13   6.4   3.5 | -14.1   6.6  315  23 12   6.6   3.6
 15000 -13.3   8.1  330  24 12   7.4   4.1 | -13.1   8.4  310  21 11   7.5   4.1
 14500 -12.2  10.0  330  22 11   7.3   4.0 | -11.9  10.6  305  18  9   7.9   4.3
 14000 -11.1  12.0  330  20 10   7.8   4.3 | -10.1  13.8  300  14  7   8.3   4.6
 13500  -9.9  14.2  330  18  9   7.8   4.3 |  -8.9  16.0  295  12  6   8.3   4.6
 13000  -8.7  16.3  330  16  8   8.4   4.6 |  -7.6  18.3  295  11  6   8.3   4.6
 12500  -7.5  18.5  335  13  7   8.8   4.8 |  -6.4  20.5  285   9  5   8.4   4.6
 12000  -6.3  20.7  335  11  6   7.9   4.3 |  -5.2  22.6  280   8  4   7.6   4.2
 11750  -5.6  21.9  335  10  5   8.9   4.9 |  -4.7  23.5  275   7  4   7.8   4.3
 11500  -5.0  23.0  335  10  5   8.7   4.8 |  -4.1  24.6  270   6  3   7.7   4.2
 11250  -4.3  24.3  335   9  5   8.6   4.7 |  -3.5  25.7  265   5  3   7.9   4.3
 11000  -3.7  25.3  335   8  4   8.2   4.5 |  -2.9  26.8  265   5  3   7.8   4.3
 10750  -3.1  26.4  335   8  4   7.9   4.3 |  -2.4  27.7  255   5  2   7.4   4.1
 10500  -2.5  27.5  335   7  3   8.4   4.6 |  -1.8  28.8  250   4  2   7.7   4.2
 10250  -1.9  28.6  335   6  3   6.6   3.6 |  -1.3  29.7  240   4  2   6.8   3.7
 10000  -1.6  29.1  330   5  2   3.6   2.0 |  -0.9  30.4  230   4  2   5.9   3.2
  9750  -1.3  29.7  310   4  2   4.3   2.4 |  -0.4  31.3  225   4  2   6.0   3.3
  9500  -0.9  30.4  290   4  2   6.9   3.8 |  -0.0  32.0  215   4  2   6.8   3.7
  9250  -0.5  31.1  270   4  2   1.6   0.9 |   0.4  32.7  210   5  2   3.4   1.9
  9000  -0.7  30.7  245   5  3  -4.3  -2.4 |   0.4  32.7  205   6  3  -0.3  -0.2
  8750  -1.0  30.2  230   6  3  -2.8  -1.6 |   0.4  32.7  200   8  4   3.5   1.9
  8500  -1.2  29.8  225   8  4  -1.9  -1.0 |   0.8  33.4  195  10  5   6.9   3.8
  8250  -1.4  29.5  220  10  5   0.7   0.4 |   1.4  34.5  190  11  6   8.2   4.5
  8000  -1.2  29.8  210  10  5   2.4   1.3 |   2.0  35.6  190  12  6   9.5   5.2
  7750  -1.1  30.0  205  10  5   2.3   1.3 |   2.7  36.9  185  12  6   8.6   4.7
  7500  -0.9  30.4  195  10  5   6.1   3.3 |   3.3  37.9  185  12  6  10.2   5.6
  7250  -0.3  31.5  190  10  5   9.2   5.1 |   4.2  39.6  185  11  6  12.6   6.9
  7000   0.4  32.7  190   9  5   8.2   4.5 |   5.1  41.2  185  11  6  11.3   6.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/17/2014 at 1500 MDT          |       04/17/2014 at 1800 MDT
                                           |
K index... +10.3  LI... +3.3               | K index... +9.7  LI... +2.8
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 -58.7 -73.7  310  23 12  -0.1  -0.1 | -59.8 -75.6  310  27 14  -0.6  -0.3
 45000 -58.9 -74.0  315  35 18  -1.2  -0.7 | -60.8 -77.4  315  37 19  -2.3  -1.3
 40000 -62.3 -80.1  330  53 27  -2.3  -1.3 | -65.5 -85.9  340  46 24  -3.2  -1.7
 38000 -61.1 -78.0  335  56 29   5.8   3.2 | -63.2 -81.8  340  47 24   8.5   4.7
 36000 -57.6 -71.7  335  56 29   5.9   3.2 | -58.1 -72.6  340  44 23   8.5   4.7
 34000 -53.8 -64.8  340  56 29   8.6   4.7 | -53.0 -63.4  340  42 21   8.8   4.8
 32000 -48.6 -55.5  335  58 30   8.6   4.7 | -47.7 -53.9  330  42 22   8.8   4.9
 30000 -42.9 -45.2  335  59 30   8.1   4.5 | -41.8 -43.2  325  43 22   8.7   4.8
 29000 -40.5 -40.9  330  58 30   8.1   4.5 | -39.1 -38.4  325  44 23   8.7   4.8
 28000 -38.0 -36.4  330  57 30   8.1   4.5 | -36.5 -33.7  325  45 23   8.8   4.8
 27000 -35.7 -32.3  330  56 29   7.4   4.1 | -34.0 -29.2  325  45 23   7.3   4.0
 26000 -33.4 -28.1  325  53 27   7.4   4.1 | -31.8 -25.2  325  42 22   7.4   4.1
 25000 -31.2 -24.2  325  49 25   7.4   4.1 | -29.6 -21.3  320  39 20   7.4   4.1
 24000 -29.0 -20.2  320  46 24   7.7   4.3 | -27.4 -17.3  320  37 19   7.7   4.2
 23000 -26.6 -15.9  320  43 22   7.9   4.3 | -25.1 -13.2  320  35 18   7.7   4.2
 22000 -24.3 -11.7  320  41 21   7.9   4.3 | -22.8  -9.0  315  34 18   7.7   4.2
 21000 -21.9  -7.4  320  39 20   7.6   4.2 | -20.5  -4.9  315  34 17   7.4   4.1
 20000 -19.7  -3.5  315  38 20   7.6   4.2 | -18.2  -0.8  315  34 17   7.4   4.1
 19500 -18.5  -1.3  310  38 20   7.7   4.2 | -17.1   1.2  315  34 17   7.5   4.1
 19000 -17.4   0.7  310  38 20   7.8   4.3 | -16.0   3.2  310  34 18   7.5   4.1
 18500 -16.4   2.5  305  38 19   3.7   2.1 | -15.0   5.0  310  34 18   6.7   3.7
 18000 -16.0   3.2  305  36 19   2.8   1.5 | -14.0   6.8  310  34 18   6.6   3.6
 17500 -15.6   3.9  305  35 18   3.4   1.8 | -13.0   8.6  310  34 18   5.8   3.2
 17000 -14.9   5.2  305  32 17   5.8   3.2 | -12.3   9.9  305  33 17   4.1   2.2
 16500 -14.0   6.8  300  30 15   5.6   3.1 | -11.7  10.9  300  32 16   3.8   2.1
 16000 -13.1   8.4  300  27 14   7.0   3.9 | -11.0  12.2  295  31 16   6.6   3.6
 15500 -12.1  10.2  295  25 13   7.0   3.8 | -10.0  14.0  285  31 16   6.3   3.4
 15000 -11.1  12.0  290  23 12   7.4   4.1 |  -9.1  15.6  280  31 16   7.3   4.0
 14500  -9.4  15.1  280  22 12   7.6   4.2 |  -7.4  18.7  275  32 17   7.6   4.2
 14000  -8.3  17.1  275  21 11   7.6   4.2 |  -6.3  20.7  270  32 16   7.5   4.1
 13500  -7.2  19.0  270  19 10   7.7   4.2 |  -5.2  22.6  270  31 16   7.5   4.1
 13000  -6.0  21.2  265  18  9   7.8   4.3 |  -4.1  24.6  265  29 15   8.3   4.6
 12500  -4.9  23.2  255  16  8   7.9   4.3 |  -2.9  26.8  265  27 14   8.4   4.6
 12000  -3.8  25.2  250  14  7   7.0   3.9 |  -1.8  28.8  260  25 13   7.2   4.0
 11750  -3.3  26.1  245  14  7   7.6   4.2 |  -1.3  29.7  260  25 13   7.2   4.0
 11500  -2.7  27.1  240  13  7   7.3   4.0 |  -0.7  30.7  255  24 12   7.8   4.3
 11250  -2.2  28.0  235  13  7   7.8   4.3 |  -0.2  31.6  255  24 12   5.5   3.0
 11000  -1.6  29.1  235  13  7   6.3   3.5 |   0.1  32.2  250  23 12   4.0   2.2
 10750  -1.3  29.7  230  12  6   4.7   2.6 |   0.5  32.9  245  23 12   5.0   2.7
 10500  -0.9  30.4  225  12  6   5.4   3.0 |   0.8  33.4  240  22 11   5.2   2.9
 10250  -0.5  31.1  220  13  6   4.5   2.5 |   1.1  34.0  235  22 11   3.4   1.9
 10000  -0.2  31.6  210  13  7   4.8   2.6 |   1.3  34.3  225  21 11   2.8   1.6
  9750   0.2  32.4  205  13  7   6.9   3.8 |   1.6  34.9  220  21 11   5.9   3.2
  9500   0.7  33.3  200  14  7   7.8   4.3 |   2.1  35.8  215  20 10   6.5   3.6
  9250   1.3  34.3  190  16  8   6.9   3.8 |   2.6  36.7  210  20 10   6.7   3.7
  9000   1.7  35.1  190  16  8   5.8   3.2 |   3.1  37.6  205  20 10   7.1   3.9
  8750   2.2  36.0  190  17  9   9.0   4.9 |   3.6  38.5  200  20 10   8.9   4.9
  8500   3.0  37.4  185  17  9  11.5   6.3 |   4.4  39.9  195  20 10  10.4   5.7
  8250   3.8  38.8  185  16  8  10.4   5.7 |   5.1  41.2  195  20 10   9.8   5.4
  8000   4.6  40.3  185  16  8  10.7   5.9 |   5.8  42.4  195  19 10   9.9   5.4
  7750   5.4  41.7  185  16  8   9.9   5.4 |   6.6  43.9  190  19 10   9.3   5.1
  7500   6.1  43.0  185  16  8  10.5   5.8 |   7.2  45.0  190  18  9   7.7   4.2
  7250   6.9  44.4  180  15  8  12.5   6.9 |   7.7  45.9  190  16  8   7.0   3.8
  7000   7.8  46.0  180  15  8  11.9   6.5 |   8.2  46.8  190  15  8   6.9   3.8
  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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