Soaring Guidance
Issued by NWS Pueblo, CO

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Soaring Forecast
National Weather Service Pueblo, Colorado
0416 MDT Tuesday, April 22, 2014

This forecast is for Tuesday, April 22, 2014:

If the trigger temperature of 62.2 F/16.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1073 ft/min (5.5 m/s)
   Maximum height of thermals.................. 19757 ft MSL (12999 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12354 ft MSL (5596 ft AGL)
Thermal soaring outlook for Wednesday 04/23.... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Increasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 16607 ft MSL (9849 ft AGL)
Wave soaring outlook for Wednesday 04/23....... Poor

Remarks...

Sunrise/Sunset.................... 06:12:40 / 19:42:04 MDT
Total possible sunshine........... 13 hr 29 min 25 sec (809 min 25 sec)
Altitude of sun at 12:57:32 MDT... 63.41 degrees

Upper air data from numerical model forecast valid on 04/22/2014 at 0600 MDT

Freezing level.................. 13261 ft MSL (6503 ft AGL)
Convective condensation level... 15239 ft MSL (8481 ft AGL)
Lifted condensation level....... 15883 ft MSL (9125 ft AGL)
Lifted index.................... -1.6
K index......................... +16.2

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  -64.2 -83.6   275   42   22   1.2   0.7      M     M       M      M    M
 45000  -62.4 -80.3   280   49   25   0.8   0.4      M     M       M      M    M
 40000  -61.2 -78.2   280   51   26   0.5   0.3      M     M       M      M    M
 38000  -57.7 -71.9   280   49   25   7.1   3.9      M     M       M      M    M
 36000  -53.4 -64.1   280   47   24   7.1   3.9      M     M       M      M    M
 34000  -48.8 -55.8   285   42   22   8.3   4.6      M     M       M      M    M
 32000  -43.8 -46.8   285   35   18   8.3   4.6      M     M       M      M    M
 30000  -38.3 -36.9   285   28   14   8.2   4.5   31.4  88.5     7.9      M    M
 29000  -35.8 -32.4   280   24   13   8.2   4.5   30.8  87.4     7.5      M    M
 28000  -33.4 -28.1   280   21   11   8.2   4.5   30.3  86.5     7.2      M    M
 27000  -31.0 -23.8   275   18    9   7.7   4.2   29.6  85.2     6.7      M    M
 26000  -28.7 -19.7   280   17    8   7.7   4.2   28.7  83.7     6.2      M    M
 25000  -26.3 -15.3   280   15    8   7.7   4.2   28.0  82.5     5.7      M    M
 24000  -24.3 -11.7   280   13    7   4.8   2.7   27.0  80.5     4.8      M    M
 23000  -22.9  -9.2   275   13    7   5.0   2.7   25.2  77.3     3.4      M    M
 22000  -21.4  -6.5   270   13    7   5.1   2.8   23.6  74.4     2.0      M    M
 21000  -19.5  -3.1   270   13    7   7.4   4.0   22.3  72.2     0.9      M    M
 20000  -17.3   0.9   280   14    7   7.5   4.1   21.5  70.7     0.2      M    M
 19500  -16.2   2.8   280   14    7   7.5   4.1   21.1  70.0    -0.1   1254  6.4
 19000  -15.1   4.8   285   15    8   7.6   4.2   20.8  69.4    -0.4   1207  6.1
 18500  -13.9   7.0   285   16    8   8.2   4.5   20.5  68.9    -0.7   1156  5.9
 18000  -12.7   9.1   285   18    9   8.2   4.5   20.2  68.4    -1.0   1105  5.6
 17500  -11.5  11.3   285   20   10   8.4   4.6   20.0  68.0    -1.2   1054  5.4
 17000  -10.3  13.5   285   20   11   8.4   4.6   19.7  67.5    -1.5   1002  5.1
 16500   -9.0  15.8   280   21   11   8.5   4.7   19.5  67.2    -1.7    950  4.8
 16000   -7.8  18.0   280   22   11   8.6   4.7   19.3  66.8    -1.9    898  4.6
 15500   -6.5  20.3   275   22   11   8.6   4.7   19.1  66.5    -2.2    845  4.3
 15000   -4.6  23.7   275   21   11   9.1   5.0   18.9  66.1    -2.4    764  3.9
 14500   -3.2  26.2   270   19   10   9.2   5.1   18.8  65.9    -2.5    709  3.6
 14000   -1.8  28.8   270   19   10   9.6   5.3   18.8  65.8    -2.6    652  3.3
 13500   -0.4  31.3   265   18    9   9.5   5.2   18.8  65.8    -2.7    595  3.0
 13000    0.9  33.6   265   18    9   8.9   4.9   18.7  65.6    -2.8    540  2.7
 12500    2.3  36.1   255   18    9   8.5   4.7   18.5  65.4    -3.0    486  2.5
 12000    3.4  38.1   255   18    9   8.0   4.4   18.3  64.9    -3.3    436  2.2
 11750    4.0  39.2   250   18    9   7.9   4.4   18.1  64.6    -3.4    411  2.1
 11500    4.6  40.3   245   18    9   8.1   4.4   18.0  64.4    -3.6    386  2.0
 11250    5.2  41.4   245   18    9   7.0   3.9   17.8  64.1    -3.7    362  1.8
 11000    5.6  42.1   240   18    9   6.7   3.6   17.6  63.6    -4.0    340  1.7
 10750    6.2  43.2   240   18    9   7.2   4.0   17.4  63.3    -4.2    317  1.6
 10500    6.7  44.1   235   18    9   7.3   4.0   17.2  62.9    -4.5    294  1.5
 10250    7.2  45.0   235   18    9   5.5   3.0   17.0  62.5    -4.7    272  1.4
 10000    7.5  45.5   230   18    9   4.6   2.5   16.5  61.8    -5.1    255  1.3
  9750    7.9  46.2   225   17    9   6.0   3.3   16.2  61.2    -5.5    236  1.2
  9500    8.3  46.9   220   17    9   5.8   3.2   15.9  60.7    -5.8    216  1.1
  9250    8.7  47.7   220   17    9   4.4   2.4   15.6  60.1    -6.2    197  1.0
  9000    8.9  48.0   215   16    8   3.2   1.8   15.1  59.2    -6.7    183  0.9
  8750    9.2  48.6   215   15    8   4.6   2.5   14.7  58.4    -7.2    168  0.9
  8500    9.5  49.1   210   15    8   2.6   1.5   14.2  57.6    -7.6    152  0.8
  8250    9.4  48.9   210   15    8  -2.1  -1.2   13.5  56.3    -8.4    145  0.7
  8000    9.1  48.4   205   14    7  -6.4  -3.5   12.4  54.4    -9.5    147  0.7
  7750    8.8  47.8   205   13    7   3.1   1.7   11.4  52.5   -10.6    150  0.8
  7500    9.1  48.4   200   12    6  -3.0  -1.7   11.1  51.9   -11.0    132  0.7
  7250    8.0  46.4   200   10    5 -21.7 -11.9    9.5  49.2   -12.5    158  0.8
  7000    6.7  44.1   205    8    4 -11.4  -6.3    7.9  46.1   -14.1    191  1.0
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/22/2014 at 0900 MDT          |       04/22/2014 at 1200 MDT
                                           |
K index... +15.2  LI... -0.3               | K index... +20.5  LI... -1.6
CAPE... +20.0  CIN... -91.7                | CAPE... +124.4  CIN... -11.9
                                           |
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 -64.8 -84.6  270  40 20   1.0   0.5 | -65.5 -85.9  265  36 18   1.3   0.7
 45000 -63.2 -81.8  270  47 24   1.1   0.6 | -63.4 -82.1  265  52 27   1.3   0.7
 40000 -61.5 -78.7  265  50 26   0.9   0.5 | -61.5 -78.7  260  56 29   0.9   0.5
 38000 -57.8 -72.0  270  49 25   7.5   4.1 | -57.6 -71.7  260  54 28   7.6   4.2
 36000 -53.2 -63.8  270  47 24   7.5   4.1 | -53.0 -63.4  260  52 27   7.6   4.2
 34000 -48.6 -55.5  270  43 22   8.1   4.4 | -48.4 -55.1  260  49 25   8.0   4.4
 32000 -43.7 -46.7  270  38 20   8.1   4.4 | -43.6 -46.5  260  44 23   8.0   4.4
 30000 -38.3 -36.9  270  32 16   8.0   4.4 | -38.8 -37.8  260  39 20   8.1   4.4
 29000 -35.9 -32.6  265  28 15   8.0   4.4 | -35.8 -32.4  255  36 18   8.1   4.4
 28000 -33.5 -28.3  260  25 13   8.0   4.4 | -33.4 -28.1  255  33 17   8.1   4.4
 27000 -31.2 -24.2  260  23 12   7.6   4.1 | -31.1 -24.0  250  31 16   7.2   4.0
 26000 -28.9 -20.0  255  21 11   7.6   4.1 | -29.0 -20.2  250  28 15   7.2   4.0
 25000 -26.6 -15.9  255  19 10   7.5   4.1 | -26.8 -16.2  250  26 13   7.2   4.0
 24000 -24.6 -12.3  255  18  9   5.1   2.8 | -24.8 -12.6  250  23 12   5.9   3.2
 23000 -23.1  -9.6  260  17  9   5.3   2.9 | -23.1  -9.6  245  21 11   6.0   3.3
 22000 -21.5  -6.7  260  16  8   5.4   3.0 | -21.3  -6.3  245  18  9   6.1   3.3
 21000 -19.6  -3.3  265  16  8   7.8   4.3 | -19.2  -2.6  245  17  9   8.0   4.4
 20000 -17.3   0.9  270  16  8   7.8   4.3 | -16.8   1.8  250  17  8   8.1   4.4
 19500 -16.1   3.0  275  16  8   7.9   4.3 | -15.6   3.9  250  16  8   8.1   4.4
 19000 -15.0   5.0  275  16  8   8.0   4.4 | -14.4   6.1  250  16  8   8.1   4.5
 18500 -13.7   7.3  275  17  9   8.6   4.7 | -13.3   8.1  255  17  9   8.1   4.4
 18000 -12.4   9.7  280  18 10   8.5   4.7 | -12.1  10.2  255  18  9   8.1   4.4
 17500 -11.2  11.8  280  19 10   8.6   4.7 | -10.9  12.4  255  18  9   8.1   4.5
 17000  -9.9  14.2  280  19 10   8.6   4.7 |  -9.7  14.5  255  18  9   8.1   4.5
 16500  -8.6  16.5  280  20 10   8.7   4.8 |  -8.5  16.7  255  18  9   8.0   4.4
 16000  -7.3  18.9  285  20 10   8.9   4.9 |  -7.3  18.9  260  18  9   7.8   4.3
 15500  -6.0  21.2  285  20 10   8.9   4.9 |  -6.1  21.0  260  18  9   7.8   4.3
 15000  -4.1  24.6  280  20 11   8.8   4.8 |  -5.0  23.0  260  18  9   7.9   4.3
 14500  -2.8  27.0  280  21 11   8.8   4.9 |  -3.3  26.1  260  18  9   8.2   4.5
 14000  -1.5  29.3  275  23 12   9.0   5.0 |  -2.0  28.4  260  18 10   9.2   5.1
 13500  -0.1  31.8  270  24 12   9.1   5.0 |  -0.6  30.9  255  18 10   9.2   5.0
 13000   1.3  34.3  270  25 13   9.6   5.3 |   0.8  33.4  250  18  9  10.4   5.7
 12500   2.7  36.9  270  25 13   9.0   4.9 |   2.4  36.3  250  18  9   8.3   4.6
 12000   4.0  39.2  270  25 13   9.0   4.9 |   3.6  38.5  245  17  9  10.4   5.7
 11750   4.6  40.3  265  25 13   8.8   4.8 |   4.3  39.7  245  17  9   9.7   5.3
 11500   5.3  41.5  265  25 13   9.1   5.0 |   5.1  41.2  245  17  9  10.2   5.6
 11250   5.9  42.6  265  24 12   8.0   4.4 |   5.8  42.4  245  17  9   8.7   4.8
 11000   6.5  43.7  265  23 12   7.6   4.2 |   6.4  43.5  240  17  9   8.9   4.9
 10750   7.1  44.8  260  22 11   8.1   4.4 |   7.2  45.0  240  17  9   9.9   5.4
 10500   7.7  45.9  260  21 11   8.6   4.7 |   7.9  46.2  240  17  9  11.0   6.0
 10250   8.3  46.9  255  20 10   6.2   3.4 |   8.6  47.5  240  17  9   5.6   3.1
 10000   8.6  47.5  255  19 10   5.7   3.1 |   8.8  47.8  235  17  9   5.8   3.2
  9750   9.2  48.6  250  17  9   7.9   4.4 |   9.6  49.3  235  16  8  11.6   6.4
  9500   9.7  49.5  250  15  8   8.1   4.4 |  10.4  50.7  230  16  8  10.4   5.7
  9250  10.3  50.5  245  14  7   4.5   2.5 |  11.1  52.0  230  16  8   9.5   5.2
  9000  10.4  50.7  240  14  7   1.4   0.8 |  11.8  53.2  225  15  8   8.6   4.7
  8750  10.5  50.9  235  14  7   3.2   1.7 |  12.4  54.3  220  15  8  10.3   5.6
  8500  10.8  51.4  230  15  8   3.0   1.7 |  13.2  55.8  220  15  8  11.0   6.0
  8250  10.9  51.6  230  15  8   0.6   0.3 |  14.0  57.2  220  14  7  10.5   5.8
  8000  10.8  51.4  225  14  7  -1.2  -0.7 |  14.8  58.6  215  14  7  10.8   5.9
  7750  10.6  51.1  220  13  7   1.1   0.6 |  15.6  60.1  215  14  7   9.6   5.2
  7500  10.8  51.4  215  11  5   4.6   2.5 |  16.3  61.3  210  13  7   9.9   5.4
  7250  11.2  52.2  210   9  5   5.9   3.2 |  17.1  62.8  210  13  7  13.2   7.2
  7000  11.6  52.9  205   9  4   6.0   3.3 |  18.1  64.6  210  13  6  14.1   7.7
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/22/2014 at 1500 MDT          |       04/22/2014 at 1800 MDT
                                           |
K index... +24.3  LI... -1.8               | K index... +20.7  LI... -0.2
CAPE... +141.3  CIN... -7.9                | CAPE... +61.3  CIN... -42.7
                                           |
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 -65.3 -85.5  255  38 20   1.3   0.7 | -65.3 -85.5  245  41 21   0.5   0.3
 45000 -63.4 -82.1  260  57 29   1.0   0.5 | -64.4 -83.9  255  55 28   2.1   1.2
 40000 -61.8 -79.2  255  64 33   0.7   0.4 | -61.3 -78.3  255  54 28   1.6   0.9
 38000 -57.9 -72.2  255  61 32   7.8   4.3 | -57.4 -71.3  255  53 27   7.7   4.2
 36000 -53.2 -63.8  255  58 30   7.8   4.3 | -52.8 -63.0  250  53 27   7.7   4.2
 34000 -48.6 -55.5  255  54 28   7.7   4.2 | -48.2 -54.8  250  49 25   7.7   4.2
 32000 -44.0 -47.2  250  48 25   7.7   4.2 | -43.6 -46.5  245  42 21   7.7   4.2
 30000 -39.0 -38.2  250  43 22   9.1   5.0 | -38.8 -37.8  245  38 19   8.5   4.6
 29000 -35.6 -32.1  250  41 21   9.1   5.0 | -36.2 -33.2  245  38 20   8.5   4.6
 28000 -32.9 -27.2  245  39 20   9.1   5.0 | -33.7 -28.7  245  38 20   8.5   4.6
 27000 -30.5 -22.9  245  37 19   7.0   3.9 | -30.9 -23.6  245  38 19   6.4   3.5
 26000 -28.4 -19.1  240  33 17   7.0   3.9 | -29.0 -20.2  240  36 19   6.4   3.5
 25000 -26.3 -15.3  240  30 16   7.1   3.9 | -27.1 -16.8  240  35 18   6.4   3.5
 24000 -24.3 -11.7  235  28 14   6.9   3.8 | -25.1 -13.2  235  34 18   8.1   4.5
 23000 -22.2  -8.0  235  27 14   6.9   3.8 | -22.7  -8.9  235  34 17   8.0   4.4
 22000 -20.2  -4.4  235  26 13   6.9   3.8 | -20.3  -4.5  235  33 17   8.0   4.4
 21000 -18.2  -0.8  235  25 13   7.0   3.9 | -17.9  -0.2  235  34 17   8.3   4.6
 20000 -16.1   3.0  235  24 13   7.0   3.9 | -15.4   4.3  240  35 18   8.4   4.6
 19500 -15.0   5.0  235  24 12   7.0   3.9 | -14.2   6.4  240  36 18   8.4   4.6
 19000 -14.0   6.8  235  24 12   7.1   3.9 | -13.0   8.6  245  36 19   8.4   4.6
 18500 -13.0   8.6  235  24 12   7.1   3.9 | -11.8  10.8  245  37 19   7.5   4.1
 18000 -11.9  10.6  235  25 13   7.1   3.9 | -10.7  12.7  245  37 19   7.6   4.2
 17500 -10.9  12.4  235  25 13   7.2   4.0 |  -9.6  14.7  245  37 19   7.5   4.1
 17000  -9.8  14.4  235  25 13   7.3   4.0 |  -8.5  16.7  245  37 19   7.5   4.1
 16500  -8.7  16.3  235  24 12   7.3   4.0 |  -7.4  18.7  245  37 19   7.5   4.1
 16000  -7.6  18.3  235  24 12   7.6   4.2 |  -6.3  20.7  245  37 19   7.4   4.1
 15500  -6.5  20.3  235  24 12   7.6   4.1 |  -5.2  22.6  245  36 18   7.5   4.1
 15000  -5.4  22.3  230  24 12   8.6   4.7 |  -4.1  24.6  245  34 18   7.2   4.0
 14500  -3.5  25.7  230  23 12   8.7   4.8 |  -3.1  26.4  245  33 17   7.2   4.0
 14000  -2.2  28.0  225  23 12   9.6   5.2 |  -1.4  29.5  240  30 15   8.3   4.5
 13500  -0.8  30.6  225  23 12   9.5   5.2 |  -0.3  31.5  240  28 14   8.1   4.5
 13000   0.6  33.1  225  23 12   9.7   5.3 |   1.0  33.8  240  27 14   9.0   4.9
 12500   2.1  35.8  225  24 12  10.6   5.8 |   2.3  36.1  240  26 13   9.2   5.1
 12000   3.6  38.5  220  23 12   9.1   5.0 |   3.6  38.5  235  24 12   8.9   4.9
 11750   4.3  39.7  220  23 12   9.3   5.1 |   4.3  39.7  235  23 12   8.9   4.9
 11500   5.0  41.0  220  23 12   8.8   4.9 |   4.9  40.8  235  23 12   8.6   4.7
 11250   5.7  42.3  220  24 12  10.4   5.7 |   5.6  42.1  235  22 11   9.8   5.4
 11000   6.5  43.7  220  23 12  10.8   5.9 |   6.4  43.5  230  22 11  10.0   5.5
 10750   7.2  45.0  215  23 12   9.4   5.2 |   7.0  44.6  230  21 11   8.8   4.8
 10500   7.9  46.2  215  23 12  10.1   5.5 |   7.7  45.9  230  21 11   9.5   5.2
 10250   8.7  47.7  215  23 12   8.7   4.8 |   8.4  47.1  225  20 10   7.9   4.3
 10000   9.3  48.7  215  23 12   9.2   5.0 |   8.9  48.0  225  20 10   8.5   4.6
  9750  10.1  50.2  215  23 12  10.7   5.9 |   9.7  49.5  220  19 10  10.4   5.7
  9500  10.8  51.4  210  23 12  10.5   5.8 |  10.4  50.7  220  19 10  10.0   5.5
  9250  11.6  52.9  210  23 12   9.8   5.4 |  11.1  52.0  220  19 10   9.7   5.3
  9000  12.3  54.1  210  23 12   9.1   5.0 |  11.8  53.2  215  18  9   9.0   4.9
  8750  13.0  55.4  210  22 11  10.1   5.6 |  12.5  54.5  215  18  9   9.4   5.2
  8500  13.8  56.8  210  22 11  10.7   5.9 |  13.2  55.8  210  18  9   9.8   5.4
  8250  14.6  58.3  205  22 11  10.2   5.6 |  14.0  57.2  210  17  9   9.6   5.3
  8000  15.3  59.5  205  21 11  10.1   5.5 |  14.7  58.5  205  17  9  10.0   5.5
  7750  16.0  60.8  205  21 11   9.4   5.1 |  15.4  59.7  205  16  8   9.1   5.0
  7500  16.7  62.1  205  19 10   8.3   4.5 |  16.0  60.8  205  15  8   8.5   4.7
  7250  17.3  63.1  205  18  9   8.1   4.4 |  16.6  61.9  200  14  7   6.6   3.6
  7000  17.8  64.0  205  17  9   7.5   4.1 |  16.9  62.4  200  13  7   1.8   1.0
  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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