Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 281020
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0420 MDT Thursday, August 28, 2014

This forecast is for Thursday, August 28, 2014:

If the trigger temperature of 63.0 F/17.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 206 ft/min (1.0 m/s)
   Maximum height of thermals.................. 11598 ft MSL (4840 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1400 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................. 7929 ft MSL (1171 ft AGL)
Thermal soaring outlook for Friday 08/29....... 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)................ Weak PVA
Potential height of wave....................... 25216 ft MSL (18458 ft AGL)
Wave soaring outlook for Friday 08/29.......... Poor

Remarks...

Sunrise/Sunset.................... 06:24:17 / 19:36:43 MDT
Total possible sunshine........... 13 hr 12 min 26 sec (792 min 26 sec)
Altitude of sun at 13:00:05 MDT... 60.58 degrees

Upper air data from numerical model forecast valid on 08/28/2014 at 0600 MDT

Freezing level.................. 13585 ft MSL (6827 ft AGL)
Convective condensation level... 14010 ft MSL (7252 ft AGL)
Lifted condensation level....... 12973 ft MSL (6215 ft AGL)
Lifted index.................... +0.9
K index......................... +24.5

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  -59.4 -74.9   215   19   10   2.7   1.5      M     M       M      M    M
 45000  -54.5 -66.1   215   32   16   4.2   2.3      M     M       M      M    M
 40000  -48.4 -55.1   225   32   17   1.0   0.5      M     M       M      M    M
 38000  -48.3 -54.9   230   29   15   0.0   0.0      M     M       M      M    M
 36000  -48.3 -54.9   235   27   14  -0.0  -0.0      M     M       M      M    M
 34000  -45.8 -50.4   245   23   12   6.8   3.7      M     M       M      M    M
 32000  -41.7 -43.1   250   20   10   6.8   3.7      M     M       M      M    M
 30000  -36.2 -33.2   265   17    9   9.2   5.0   33.1  91.6    11.9      M    M
 29000  -33.4 -28.1   270   16    8   9.2   5.0   32.9  91.3    11.8      M    M
 28000  -30.7 -23.3   275   15    8   9.1   5.0   32.8  91.1    11.9      M    M
 27000  -28.1 -18.6   275   15    8   8.6   4.7   32.4  90.3    11.6      M    M
 26000  -25.5 -13.9   275   15    8   8.6   4.7   31.9  89.4    11.4      M    M
 25000  -23.0  -9.4   275   16    8   8.7   4.8   31.6  88.8    11.2      M    M
 24000  -20.7  -5.3   275   16    8   7.3   4.0   30.9  87.5    10.7      M    M
 23000  -18.5  -1.3   270   16    8   7.3   4.0   29.9  85.9    10.0      M    M
 22000  -16.4   2.5   265   17    9   7.5   4.1   29.2  84.5     9.4      M    M
 21000  -14.4   6.1   260   18    9   6.2   3.4   28.0  82.4     8.5      M    M
 20000  -12.6   9.3   255   19   10   6.2   3.4   26.8  80.2     7.5      M    M
 19500  -11.7  10.9   255   19   10   6.2   3.4   26.2  79.1     7.0      M    M
 19000  -10.7  12.7   255   20   10   6.3   3.4   25.6  78.1     6.6      M    M
 18500   -9.8  14.4   255   19   10   6.4   3.5   25.0  77.1     6.0      M    M
 18000   -8.9  16.0   255   19   10   6.4   3.5   24.5  76.0     5.5      M    M
 17500   -8.0  17.6   255   19   10   5.8   3.2   23.9  74.9     5.0      M    M
 17000   -7.2  19.0   250   18    9   5.9   3.2   23.2  73.8     4.4      M    M
 16500   -6.3  20.7   250   17    9   6.2   3.4   22.6  72.7     3.8      M    M
 16000   -5.4  22.3   250   17    9   6.3   3.5   22.0  71.6     3.3      M    M
 15500   -4.5  23.9   250   16    8   6.6   3.6   21.4  70.6     2.7      M    M
 15000   -3.0  26.6   245   14    7   7.3   4.0   20.8  69.5     2.1      M    M
 14500   -1.9  28.6   245   13    7   7.7   4.2   20.4  68.8     1.7      M    M
 14000   -0.7  30.7   245   12    6   7.9   4.3   20.1  68.2     1.4      M    M
 13500    0.4  32.7   250   10    5   7.9   4.3   19.9  67.7     1.2      M    M
 13000    1.6  34.9   255    9    5   7.8   4.3   19.5  67.2     0.8      M    M
 12500    2.7  36.9   260    8    4   8.2   4.5   19.2  66.6     0.5      M    M
 12000    3.9  39.0   265    7    4   7.6   4.2   19.0  66.1     0.2      M    M
 11750    4.4  39.9   270    7    3   7.8   4.3   18.8  65.8     0.1      M    M
 11500    5.0  41.0   270    6    3   7.8   4.3   18.7  65.6    -0.1    390  2.0
 11250    5.6  42.1   275    5    3   7.8   4.3   18.5  65.3    -0.3    365  1.9
 11000    6.1  43.0   275    5    3   7.7   4.3   18.4  65.0    -0.4    341  1.7
 10750    6.7  44.1   280    4    2   7.7   4.2   18.2  64.7    -0.6    317  1.6
 10500    7.3  45.1   285    4    2   7.7   4.2   18.0  64.5    -0.8    292  1.5
 10250    7.8  46.0   290    4    2   7.2   3.9   17.9  64.2    -0.9    268  1.4
 10000    8.3  46.9   295    3    2   7.6   4.2   17.7  63.8    -1.1    245  1.2
  9750    9.0  48.2   300    3    2   8.5   4.7   17.5  63.6    -1.3    219  1.1
  9500    9.6  49.3   310    3    2   8.2   4.5   17.4  63.4    -1.4    193  1.0
  9250   10.2  50.4   315    4    2   7.6   4.2   17.3  63.1    -1.5    168  0.9
  9000   10.7  51.3   315    4    2   7.3   4.0   17.1  62.8    -1.7    144  0.7
  8750   11.3  52.3   320    4    2   8.0   4.4   17.0  62.5    -1.8    120  0.6
  8500   11.8  53.2   320    5    3   6.3   3.4   16.8  62.2    -2.0     96  0.5
  8250   12.2  54.0   315    6    3   3.7   2.0   16.4  61.5    -2.4     78  0.4
  8000   12.4  54.3   315    7    3   3.6   2.0   15.9  60.7    -2.9     63  0.3
  7750   12.7  54.9   310    7    4   4.1   2.2   15.5  59.9    -3.3     47  0.2
  7500   12.7  54.9   300    8    4  -6.3  -3.5   14.9  58.8    -4.0     40  0.2
  7250   11.7  53.1   300    7    4 -16.1  -8.9   13.5  56.3    -5.4     63  0.3
  7000   10.7  51.3   300    6    3  -8.6  -4.7   12.2  54.0    -6.8     87  0.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/28/2014 at 0900 MDT          |       08/28/2014 at 1200 MDT
                                           |
K index... +26.2  LI... -0.6               | K index... +26.6  LI... -1.2
CAPE... +62.1  CIN... -92.1                | CAPE... +247.5  CIN... -0.6
                                           |
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 -58.3 -72.9  235  16  8   3.2   1.8 | -59.3 -74.7  270  13  7   3.2   1.8
 45000 -53.1 -63.6  235  24 12   3.7   2.0 | -54.2 -65.6  280  18  9   3.3   1.8
 40000 -47.6 -53.7  240  17  9   0.3   0.2 | -49.4 -56.9  310  14  7   0.9   0.5
 38000 -48.6 -55.5  250  16  8  -1.8  -1.0 | -49.3 -56.7  315  17  9   0.1   0.0
 36000 -49.7 -57.5  260  16  8  -1.8  -1.0 | -49.3 -56.7  320  20 10  -0.0  -0.0
 34000 -47.1 -52.8  265  15  8   8.5   4.7 | -46.2 -51.2  315  19 10   8.3   4.6
 32000 -42.0 -43.6  270  14  7   8.5   4.7 | -41.2 -42.2  295  17  9   8.3   4.6
 30000 -36.1 -33.0  265  13  7   8.8   4.8 | -35.4 -31.7  285  15  8   8.6   4.7
 29000 -33.5 -28.3  260  13  7   8.8   4.8 | -32.9 -27.2  280  14  7   8.6   4.7
 28000 -30.9 -23.6  250  13  7   8.8   4.8 | -30.3 -22.5  275  13  7   8.6   4.7
 27000 -28.3 -18.9  250  12  6   8.8   4.8 | -27.8 -18.0  280  13  7   8.3   4.5
 26000 -25.6 -14.1  250  11  6   8.8   4.9 | -25.3 -13.5  280  12  6   8.3   4.6
 25000 -23.0  -9.4  255  10  5   8.9   4.9 | -22.9  -9.2  280  12  6   8.4   4.6
 24000 -20.6  -5.1  260  10  5   7.4   4.1 | -20.6  -5.1  285  12  6   7.3   4.0
 23000 -18.4  -1.1  265  11  6   7.4   4.1 | -18.5  -1.3  290  12  6   7.3   4.0
 22000 -16.3   2.7  265  12  6   7.6   4.1 | -16.3   2.7  295  13  7   7.4   4.1
 21000 -14.4   6.1  275  12  6   5.9   3.2 | -14.3   6.3  295  13  7   6.9   3.8
 20000 -12.7   9.1  280  13  7   5.9   3.2 | -12.3   9.9  300  13  7   6.9   3.8
 19500 -11.9  10.6  285  13  7   6.0   3.3 | -11.3  11.7  300  13  7   6.9   3.8
 19000 -11.0  12.2  290  14  7   6.1   3.4 | -10.3  13.5  300  13  7   6.7   3.7
 18500 -10.1  13.8  290  14  7   6.3   3.5 |  -9.3  15.3  305  13  7   6.5   3.6
 18000  -9.2  15.4  290  14  7   6.4   3.5 |  -8.4  16.9  305  13  7   6.5   3.6
 17500  -8.3  17.1  290  13  7   6.3   3.5 |  -7.4  18.7  305  13  7   6.4   3.5
 17000  -7.4  18.7  285  13  7   6.3   3.5 |  -6.5  20.3  305  12  6   6.5   3.5
 16500  -6.5  20.3  285  13  7   6.0   3.3 |  -5.6  21.9  305  12  6   6.2   3.4
 16000  -5.6  21.9  280  12  6   5.8   3.2 |  -4.7  23.5  300  12  6   6.0   3.3
 15500  -4.8  23.4  275  11  6   5.9   3.2 |  -3.8  25.2  295  12  6   6.1   3.3
 15000  -3.4  25.9  270  10  5   6.7   3.7 |  -2.5  27.5  285  11  6   6.2   3.4
 14500  -2.4  27.7  270   9  4   7.1   3.9 |  -1.6  29.1  280  10  5   5.9   3.2
 14000  -1.3  29.7  275   8  4   7.5   4.1 |  -0.7  30.7  275  10  5   5.6   3.1
 13500  -0.2  31.6  280   7  3   7.4   4.1 |   0.1  32.2  275   9  5   5.7   3.1
 13000   0.9  33.6  285   6  3   7.2   4.0 |   0.9  33.6  275   7  4   6.0   3.3
 12500   1.9  35.4  300   5  2   7.7   4.2 |   1.7  35.1  280   6  3   6.7   3.7
 12000   2.9  37.2  315   4  2   6.6   3.6 |   2.8  37.0  305   4  2   7.7   4.2
 11750   3.4  38.1  320   3  2   6.7   3.7 |   3.3  37.9  325   3  2   7.6   4.2
 11500   3.9  39.0  335   3  2   7.2   4.0 |   3.8  38.8  345   3  2   8.4   4.6
 11250   4.5  40.1  345   3  1   8.1   4.5 |   4.5  40.1  355   4  2   9.9   5.4
 11000   5.1  41.2  360   3  2   7.2   4.0 |   5.2  41.4  355   4  2   9.7   5.3
 10750   5.5  41.9  010   4  2   6.4   3.5 |   5.9  42.6  360   4  2   9.2   5.0
 10500   6.0  42.8  015   4  2   6.8   3.8 |   6.6  43.9  005   4  2   9.5   5.2
 10250   6.5  43.7  020   5  2   7.8   4.3 |   7.3  45.1  005   4  2   9.9   5.4
 10000   7.1  44.8  020   5  3   7.8   4.3 |   8.1  46.6  005   4  2  10.1   5.6
  9750   7.7  45.9  020   6  3   7.1   3.9 |   8.8  47.8  005   4  2  10.3   5.6
  9500   8.2  46.8  020   7  4   7.3   4.0 |   9.6  49.3  010   4  2   9.9   5.5
  9250   8.7  47.7  020   7  4   7.6   4.2 |  10.3  50.5  010   5  2   9.2   5.1
  9000   9.3  48.7  020   8  4   7.7   4.2 |  11.0  51.8  010   5  2   9.2   5.1
  8750   9.9  49.8  020   8  4   9.4   5.2 |  11.7  53.1  010   5  2  10.6   5.8
  8500  10.6  51.1  015   8  4   9.8   5.4 |  12.5  54.5  010   5  2  11.1   6.1
  8250  11.3  52.3  015   8  4   8.9   4.9 |  13.3  55.9  010   5  2  10.5   5.8
  8000  12.0  53.6  010   8  4   8.8   4.8 |  14.1  57.4  010   5  2  10.6   5.8
  7750  12.6  54.7  005   8  4   9.8   5.4 |  14.9  58.8  015   5  2  10.5   5.7
  7500  13.3  55.9  005   8  4   9.5   5.2 |  15.7  60.3  015   5  2  11.8   6.5
  7250  13.9  57.0  360   8  4   8.1   4.4 |  16.6  61.9  015   5  2  13.2   7.2
  7000  14.6  58.3  360   7  4   9.3   5.1 |  17.5  63.5  015   5  2  12.1   6.6
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/28/2014 at 1500 MDT          |       08/28/2014 at 1800 MDT
                                           |
K index... +27.6  LI... -1.7               | K index... +27.0  LI... -0.8
CAPE... +263.4  CIN... -1.8                | CAPE... +75.8  CIN... -2.3
                                           |
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 -59.7 -75.5  300  12  6   3.1   1.7 | -60.4 -76.7  320  13  7   2.7   1.5
 45000 -55.1 -67.2  320  19 10   2.5   1.4 | -56.9 -70.4  340  24 12   1.1   0.6
 40000 -51.4 -60.5  345  27 14   2.4   1.3 | -55.0 -67.0  355  39 20   6.3   3.4
 38000 -50.0 -58.0  360  35 18   2.3   1.3 | -51.5 -60.7  360  42 22   5.7   3.2
 36000 -48.6 -55.5  010  45 23   2.4   1.3 | -48.1 -54.6  005  46 24   5.9   3.2
 34000 -44.7 -48.5  005  41 21   8.4   4.6 | -42.9 -45.2  360  45 23   9.5   5.2
 32000 -39.0 -38.2  360  28 15   8.4   4.6 | -36.5 -33.7  350  42 22   9.4   5.2
 30000 -34.1 -29.4  340  24 12   8.2   4.5 | -31.8 -25.2  355  38 20   7.5   4.1
 29000 -31.6 -24.9  330  24 12   8.3   4.5 | -29.5 -21.1  355  36 18   7.5   4.1
 28000 -29.2 -20.6  325  24 12   8.2   4.5 | -27.3 -17.1  360  33 17   7.5   4.1
 27000 -26.8 -16.2  325  23 12   7.9   4.3 | -25.1 -13.2  355  32 17   7.5   4.1
 26000 -24.5 -12.1  325  22 11   7.9   4.3 | -22.8  -9.0  350  31 16   7.5   4.1
 25000 -22.1  -7.8  325  21 11   8.0   4.4 | -20.6  -5.1  345  30 16   7.7   4.2
 24000 -20.0  -4.0  325  20 10   7.1   3.9 | -18.6  -1.5  345  29 15   6.3   3.5
 23000 -17.9  -0.2  325  19 10   7.1   3.9 | -16.7   1.9  345  27 14   6.3   3.5
 22000 -15.8   3.6  325  18  9   7.2   4.0 | -14.9   5.2  340  25 13   6.3   3.4
 21000 -13.8   7.2  325  17  9   6.6   3.6 | -12.9   8.8  340  23 12   6.8   3.7
 20000 -11.9  10.6  325  16  8   6.6   3.6 | -11.0  12.2  335  20 10   6.8   3.7
 19500 -10.9  12.4  325  15  8   6.6   3.6 | -10.0  14.0  335  19 10   6.9   3.8
 19000  -9.9  14.2  325  15  8   6.2   3.4 |  -9.0  15.8  335  18  9   6.1   3.3
 18500  -9.1  15.6  325  15  8   6.0   3.3 |  -8.2  17.2  330  18  9   5.7   3.1
 18000  -8.2  17.2  325  15  8   6.0   3.3 |  -7.4  18.7  330  18  9   5.7   3.1
 17500  -7.3  18.9  320  15  8   6.3   3.5 |  -6.6  20.1  325  18  9   5.5   3.0
 17000  -6.4  20.5  320  15  8   6.3   3.5 |  -5.8  21.6  325  18  9   5.6   3.1
 16500  -5.5  22.1  315  16  8   6.1   3.4 |  -5.0  23.0  325  18  9   5.6   3.1
 16000  -4.6  23.7  310  16  8   6.1   3.3 |  -4.2  24.4  325  17  9   5.7   3.1
 15500  -3.3  26.1  310  15  8   5.9   3.2 |  -2.9  26.8  325  16  8   6.4   3.5
 15000  -2.4  27.7  305  14  7   5.9   3.2 |  -2.0  28.4  330  15  8   6.4   3.5
 14500  -1.6  29.1  305  12  6   5.9   3.2 |  -1.0  30.2  330  14  7   5.9   3.2
 14000  -0.8  30.6  305   9  5   5.9   3.3 |  -0.3  31.5  340  13  6   5.7   3.1
 13500   0.1  32.2  310   6  3   6.6   3.6 |   0.5  32.9  355  11  6   6.5   3.6
 13000   1.1  34.0  325   4  2   7.9   4.3 |   1.6  34.9  005  10  5   8.1   4.4
 12500   2.2  36.0  360   3  2   8.3   4.6 |   2.7  36.9  015  10  5   8.1   4.4
 12000   3.5  38.3  020   3  2   9.6   5.3 |   4.0  39.2  020  10  5   9.4   5.1
 11750   4.2  39.6  025   3  2   9.6   5.3 |   4.7  40.5  020  10  5   9.2   5.1
 11500   4.9  40.8  030   3  2   9.5   5.2 |   5.4  41.7  020  10  5   9.3   5.1
 11250   5.6  42.1  030   3  2   9.5   5.2 |   6.0  42.8  020  10  5   9.6   5.2
 11000   6.3  43.3  030   3  2   9.9   5.4 |   6.8  44.2  020  10  5   9.7   5.3
 10750   7.1  44.8  035   3  2  10.0   5.5 |   7.5  45.5  020  10  5   9.7   5.3
 10500   7.8  46.0  035   3  2   9.8   5.4 |   8.2  46.8  020  10  5   9.6   5.3
 10250   8.5  47.3  035   3  2   8.8   4.8 |   8.9  48.0  020  10  5   8.8   4.9
 10000   9.2  48.6  035   3  1   9.6   5.2 |   9.6  49.3  020  10  5   9.6   5.3
  9750  10.0  50.0  040   3  1  10.9   6.0 |  10.3  50.5  020  10  5  10.8   5.9
  9500  10.7  51.3  040   3  1  10.3   5.6 |  11.1  52.0  020  10  5  10.1   5.5
  9250  11.5  52.7  040   3  1   9.6   5.3 |  11.8  53.2  020  10  5   9.2   5.0
  9000  12.2  54.0  040   3  1   9.6   5.2 |  12.5  54.5  020  10  5   9.2   5.0
  8750  12.9  55.2  045   3  1  10.6   5.8 |  13.2  55.8  020  10  5  10.7   5.9
  8500  13.7  56.7  045   3  1  10.7   5.9 |  14.1  57.4  020  10  5  10.7   5.9
  8250  14.5  58.1  045   3  1  10.1   5.5 |  14.8  58.6  020  10  5   9.6   5.3
  8000  15.3  59.5  045   3  1  10.0   5.5 |  15.5  59.9  020  10  5   9.5   5.2
  7750  16.0  60.8  050   3  1  10.6   5.8 |  16.2  61.2  020  10  5  10.1   5.5
  7500  16.8  62.2  050   3  1  11.0   6.0 |  17.0  62.6  020   9  5   8.8   4.8
  7250  17.6  63.7  050   3  1  10.6   5.8 |  17.5  63.5  020   9  5   6.9   3.8
  7000  18.3  64.9  050   3  1  10.9   6.0 |  18.0  64.4  020   9  4   8.4   4.6
  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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