Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 271147
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0547 MDT Monday, October 27, 2014

This forecast is for Monday, October 27, 2014:

If the trigger temperature of 52.8 F/11.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 250 ft/min (1.3 m/s)
   Maximum height of thermals.................. 9904 ft MSL (3146 ft AGL)

Forecast maximum temperature................... 51.0 F/11.0 C
Time of trigger temperature.................... None
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................. 8127 ft MSL (1369 ft AGL)
Thermal soaring outlook for Tuesday 10/28...... Fair

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 18542 ft MSL (11784 ft AGL)
Wave soaring outlook for Tuesday 10/28......... Poor

Remarks...

Sunrise/Sunset.................... 07:21:02 / 18:05:36 MDT
Total possible sunshine........... 10 hr 44 min 34 sec (644 min 34 sec)
Altitude of sun at 12:42:57 MDT... 38.14 degrees

Upper air data from numerical model forecast valid on 10/27/2014 at 0600 MDT

Freezing level.................. 11149 ft MSL (4391 ft AGL)
Convective condensation level... 12935 ft MSL (6177 ft AGL)
Lifted condensation level....... 11428 ft MSL (4670 ft AGL)
Lifted index.................... +2.9
K index......................... +2.7

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  -60.2 -76.4   260   56   29   1.6   0.9      M     M       M      M    M
 45000  -57.8 -72.0   255   67   35   1.3   0.7      M     M       M      M    M
 40000  -56.0 -68.8   255   82   42   1.2   0.6      M     M       M      M    M
 38000  -55.0 -67.0   255   83   43   1.9   1.0      M     M       M      M    M
 36000  -53.9 -65.0   250   82   42   1.9   1.0      M     M       M      M    M
 34000  -52.0 -61.6   250   79   41   7.0   3.8      M     M       M      M    M
 32000  -47.7 -53.9   255   72   37   7.1   3.9      M     M       M      M    M
 30000  -43.2 -45.8   255   67   34   8.8   4.8   26.5  79.7    12.2      M    M
 29000  -40.6 -41.1   255   65   33   8.8   4.8   26.1  78.9    12.1      M    M
 28000  -37.9 -36.2   255   63   32   8.8   4.8   25.7  78.3    11.9      M    M
 27000  -34.6 -30.3   255   60   31   9.5   5.2   25.5  77.8    11.9      M    M
 26000  -31.8 -25.2   250   56   29   9.5   5.2   25.3  77.5    11.9      M    M
 25000  -28.9 -20.0   245   52   27   9.5   5.2   25.2  77.3    12.0      M    M
 24000  -26.1 -15.0   240   48   25   8.6   4.7   25.2  77.3    12.1      M    M
 23000  -23.7 -10.7   245   47   24   8.2   4.5   24.5  76.1    11.7      M    M
 22000  -21.2  -6.2   245   47   24   8.2   4.5   23.9  75.1    11.3      M    M
 21000  -18.9  -2.0   250   47   24   6.9   3.8   23.4  74.0    11.0      M    M
 20000  -16.8   1.8   260   50   25   6.9   3.8   22.3  72.1    10.2      M    M
 19500  -15.8   3.6   260   51   26   6.9   3.8   21.8  71.2     9.8      M    M
 19000  -14.8   5.4   265   52   27   6.9   3.8   21.3  70.4     9.4      M    M
 18500  -13.8   7.2   265   54   28   6.4   3.5   20.9  69.6     9.1      M    M
 18000  -12.9   8.8   270   54   28   6.0   3.3   20.2  68.4     8.6      M    M
 17500  -12.0  10.4   270   53   27   6.0   3.3   19.6  67.3     8.1      M    M
 17000  -11.1  12.0   270   53   27   5.5   3.0   18.9  66.1     7.5      M    M
 16500  -10.3  13.5   270   52   27   5.6   3.0   18.2  64.8     6.9      M    M
 16000   -9.5  14.9   275   51   26   5.7   3.1   17.6  63.6     6.3      M    M
 15500   -8.7  16.3   275   50   25   5.8   3.2   16.9  62.4     5.7      M    M
 15000   -7.8  18.0   280   48   25   5.9   3.3   16.3  61.3     5.1      M    M
 14500   -7.0  19.4   280   46   24   6.1   3.4   15.7  60.2     4.5      M    M
 14000   -5.7  21.7   285   43   22   6.6   3.6   14.8  58.7     3.6      M    M
 13500   -4.8  23.4   285   41   21   6.8   3.7   14.3  57.8     3.1      M    M
 13000   -3.8  25.2   285   39   20   7.4   4.1   13.9  57.0     2.6      M    M
 12500   -2.7  27.1   285   35   18   7.9   4.3   13.6  56.5     2.3      M    M
 12000   -1.6  29.1   285   31   16   7.1   3.9   13.2  55.8     1.9      M    M
 11750   -1.1  30.0   285   29   15   7.2   3.9   13.0  55.4     1.7      M    M
 11500   -0.6  30.9   280   26   14   7.0   3.8   12.8  55.1     1.5      M    M
 11250   -0.1  31.8   280   24   12   7.7   4.2   12.6  54.7     1.3      M    M
 11000    0.5  32.9   280   21   11   7.5   4.1   12.5  54.5     1.1      M    M
 10750    1.0  33.8   275   19   10   6.3   3.5   12.2  54.0     0.9      M    M
 10500    1.4  34.5   275   16    8   6.2   3.4   12.0  53.5     0.6      M    M
 10250    1.9  35.4   275   13    7   6.7   3.7   11.7  53.1     0.3      M    M
 10000    2.3  36.1   270   10    5   4.9   2.7   11.4  52.6     0.1      M    M
  9750    2.6  36.7   275    7    4   4.4   2.4   11.0  51.8    -0.4    237  1.2
  9500    3.0  37.4   275    5    3   5.7   3.1   10.7  51.2    -0.7    218  1.1
  9250    3.4  38.1   285    4    2   5.6   3.1   10.3  50.6    -1.0    199  1.0
  9000    3.8  38.8   315    2    1   3.5   1.9   10.0  50.0    -1.4    181  0.9
  8750    4.0  39.2   350    4    2   3.0   1.7    9.4  49.0    -1.9    168  0.9
  8500    4.3  39.7   005    5    3   4.5   2.5    9.0  48.2    -2.4    152  0.8
  8250    4.6  40.3   020    7    3   4.1   2.2    8.6  47.5    -2.8    135  0.7
  8000    4.9  40.8   025    8    4   3.7   2.1    8.2  46.7    -3.3    119  0.6
  7750    5.1  41.2   030    8    4   4.2   2.3    7.7  45.9    -3.7    104  0.5
  7500    5.6  42.1   030    9    4   8.7   4.7    7.4  45.4    -4.0     83  0.4
  7250    6.0  42.8   030    9    4  -1.3  -0.7    7.2  44.9    -4.3     62  0.3
  7000    5.0  41.0   025    7    4 -26.1 -14.3    6.0  42.7    -5.4     84  0.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           10/27/2014 at 0900 MDT          |       10/27/2014 at 1200 MDT
                                           |
K index... -4.3  LI... +2.6                | K index... +3.4  LI... +2.2
CAPE... +15.8  CIN... -4.8                 | CAPE... +15.8  CIN... -3.0
                                           |
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 -59.2 -74.6  260  50 26   1.5   0.8 | -58.6 -73.5  260  40 21   0.9   0.5
 45000 -57.0 -70.6  255  59 30   1.2   0.6 | -57.2 -71.0  260  43 22   1.2   0.6
 40000 -55.6 -68.1  250  76 39   0.9   0.5 | -55.0 -67.0  255  73 38   1.4   0.8
 38000 -54.9 -66.8  250  78 40   1.1   0.6 | -54.4 -65.9  250  78 40   0.8   0.4
 36000 -54.3 -65.7  250  77 40   1.1   0.6 | -53.9 -65.0  250  78 40   0.8   0.4
 34000 -52.8 -63.0  255  76 39   7.5   4.1 | -52.8 -63.0  250  77 40   7.2   3.9
 32000 -48.4 -55.1  255  72 37   7.3   4.0 | -48.7 -55.7  250  75 39   6.8   3.8
 30000 -43.8 -46.8  255  68 35   8.8   4.8 | -44.4 -47.9  255  73 38   8.4   4.6
 29000 -41.2 -42.2  255  66 34   8.8   4.8 | -41.9 -43.4  255  72 37   8.4   4.6
 28000 -37.9 -36.2  255  65 33   8.8   4.8 | -39.5 -39.1  255  71 37   8.4   4.6
 27000 -35.2 -31.4  255  63 32   9.3   5.1 | -36.3 -33.3  255  69 36   9.4   5.2
 26000 -32.5 -26.5  250  59 30   9.3   5.1 | -33.4 -28.1  255  65 34   9.6   5.3
 25000 -29.7 -21.5  245  56 29   9.3   5.1 | -30.5 -22.9  255  61 32   9.6   5.3
 24000 -26.9 -16.4  240  53 27   8.5   4.7 | -27.7 -17.9  255  57 30   8.7   4.8
 23000 -24.6 -12.3  245  54 28   7.9   4.3 | -25.4 -13.7  255  59 31   7.7   4.2
 22000 -22.2  -8.0  255  57 29   7.9   4.3 | -23.1  -9.6  260  61 32   7.7   4.2
 21000 -19.9  -3.8  260  59 30   7.0   3.9 | -20.8  -5.4  265  63 32   7.1   3.9
 20000 -17.8  -0.0  260  58 30   6.9   3.8 | -18.7  -1.7  265  61 31   7.0   3.8
 19500 -16.8   1.8  260  58 30   6.9   3.8 | -17.7   0.1  265  59 31   7.0   3.8
 19000 -15.8   3.6  265  58 30   6.9   3.8 | -16.6   2.1  265  58 30   7.0   3.8
 18500 -14.7   5.5  265  58 30   6.5   3.5 | -15.6   3.9  265  57 29   6.9   3.8
 18000 -13.8   7.2  265  56 29   6.1   3.3 | -14.5   5.9  265  56 29   6.9   3.8
 17500 -12.9   8.8  265  55 28   6.1   3.3 | -13.5   7.7  265  55 29   7.2   3.9
 17000 -12.0  10.4  265  53 27   5.5   3.0 | -12.6   9.3  265  55 28   4.6   2.5
 16500 -11.2  11.8  265  52 27   5.6   3.1 | -11.9  10.6  265  55 29   4.8   2.7
 16000 -10.4  13.3  265  50 26   4.4   2.4 | -11.2  11.8  265  55 28   4.0   2.2
 15500  -9.8  14.4  270  47 24   4.1   2.3 | -10.7  12.7  265  51 26   3.8   2.1
 15000  -9.3  15.3  270  45 23   3.9   2.1 | -10.2  13.6  265  47 24   4.1   2.3
 14500  -8.8  16.2  270  41 21   3.2   1.8 |  -9.6  14.7  265  41 21   4.8   2.6
 14000  -8.1  17.4  275  36 18   6.7   3.7 |  -9.0  15.8  265  34 17   5.3   2.9
 13500  -7.0  19.4  275  31 16   7.9   4.3 |  -7.4  18.7  265  27 14   8.0   4.4
 13000  -5.9  21.4  275  26 14   8.5   4.7 |  -6.3  20.7  265  24 12   7.9   4.4
 12500  -4.7  23.5  275  23 12   8.9   4.9 |  -5.2  22.6  265  22 11   7.8   4.3
 12000  -3.4  25.9  270  19 10   7.7   4.2 |  -4.1  24.6  260  18  9   5.9   3.2
 11750  -2.9  26.8  265  18  9   6.9   3.8 |  -3.7  25.3  260  17  9   5.0   2.8
 11500  -2.4  27.7  265  16  8   6.7   3.7 |  -3.4  25.9  260  15  8   4.7   2.6
 11250  -1.9  28.6  260  14  7   8.1   4.5 |  -3.0  26.6  255  14  7   6.7   3.7
 11000  -1.3  29.7  255  13  7   7.4   4.0 |  -2.5  27.5  250  12  6   7.1   3.9
 10750  -0.8  30.6  250  11  6   5.3   2.9 |  -2.1  28.2  250  10  5   5.1   2.8
 10500  -0.4  31.3  250   9  5   5.7   3.1 |  -1.7  28.9  250   8  4   5.5   3.0
 10250  -0.0  32.0  245   7  4   5.7   3.1 |  -1.3  29.7  245   6  3   5.0   2.8
 10000   0.4  32.7  245   5  3   4.7   2.6 |  -0.9  30.4  240   4  2   5.0   2.8
  9750   0.7  33.3  280   3  2   4.4   2.4 |  -0.5  31.1  240   2  1   8.0   4.4
  9500   1.0  33.8  320   3  1   5.0   2.7 |   0.2  32.4  000   0  0   9.8   5.4
  9250   1.4  34.5  355   4  2   4.8   2.6 |   0.9  33.6  075   1  1   9.3   5.1
  9000   1.7  35.1  005   6  3   4.3   2.3 |   1.6  34.9  075   2  1   9.3   5.1
  8750   2.0  35.6  010   9  4   4.2   2.3 |   2.3  36.1  075   2  1   9.9   5.4
  8500   2.4  36.3  010  10  5   4.5   2.5 |   3.1  37.6  075   3  1  10.4   5.7
  8250   2.7  36.9  015  11  6   4.4   2.4 |   3.9  39.0  075   3  1  10.4   5.7
  8000   3.0  37.4  015  11  5   3.9   2.1 |   4.7  40.5  075   3  2  11.1   6.1
  7750   3.3  37.9  010  10  5   4.8   2.6 |   5.5  41.9  075   3  2  10.0   5.5
  7500   3.6  38.5  010  10  5   6.1   3.4 |   6.1  43.0  075   3  2   8.0   4.4
  7250   4.1  39.4  010   9  5   5.7   3.1 |   6.8  44.2  075   3  2  11.1   6.1
  7000   4.5  40.1  010   8  4   5.0   2.7 |   7.8  46.0  075   4  2  16.8   9.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           10/27/2014 at 1500 MDT          |       10/27/2014 at 1800 MDT
                                           |
K index... +19.7  LI... -0.1               | K index... +18.2  LI... +1.6
CAPE... +54.0  CIN... -3.6                 | CAPE... +38.7  CIN... -13.4
                                           |
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 -58.0 -72.4  270  33 17   1.4   0.8 | -58.8 -73.8  290  28 15   2.4   1.3
 45000 -55.9 -68.6  265  43 22   1.3   0.7 | -55.2 -67.4  290  42 22   1.9   1.1
 40000 -54.1 -65.4  275  61 32   1.1   0.6 | -53.0 -63.4  295  62 32   1.4   0.8
 38000 -53.6 -64.5  275  65 34   0.8   0.4 | -52.4 -62.3  300  71 37   0.4   0.2
 36000 -53.1 -63.6  275  66 34   0.8   0.4 | -52.2 -62.0  300  83 43   0.4   0.2
 34000 -52.2 -62.0  270  67 34   6.3   3.5 | -51.4 -60.5  300  92 48   7.6   4.2
 32000 -48.8 -55.8  270  67 35   5.7   3.2 | -47.2 -53.0  295  93 48   6.9   3.8
 30000 -45.1 -49.2  270  68 35   8.6   4.7 | -43.1 -45.6  295  92 47   6.5   3.5
 29000 -42.6 -44.7  270  68 35   8.3   4.6 | -40.7 -41.3  290  86 44   6.5   3.6
 28000 -40.1 -40.2  270  68 35   8.3   4.6 | -38.7 -37.7  290  81 42   6.5   3.6
 27000 -37.0 -34.6  275  68 35   8.3   4.6 | -36.8 -34.2  290  77 40   6.9   3.8
 26000 -34.5 -30.1  275  68 35   8.3   4.6 | -34.6 -30.3  285  75 39   7.2   4.0
 25000 -32.0 -25.6  275  68 35   8.3   4.6 | -32.4 -26.3  285  73 38   7.2   4.0
 24000 -29.5 -21.1  275  68 35   8.1   4.4 | -30.3 -22.5  280  71 37   7.6   4.2
 23000 -27.3 -17.1  275  67 35   7.5   4.1 | -27.8 -18.0  280  71 36   8.4   4.6
 22000 -25.0 -13.0  275  66 34   7.5   4.1 | -25.3 -13.5  280  70 36   8.4   4.6
 21000 -22.8  -9.0  275  65 34   6.8   3.7 | -22.8  -9.0  280  69 35   7.1   3.9
 20000 -20.9  -5.6  270  62 32   6.5   3.6 | -20.8  -5.4  275  63 32   6.5   3.6
 19500 -19.9  -3.8  270  61 31   6.5   3.6 | -19.9  -3.8  275  60 31   6.5   3.6
 19000 -18.9  -2.0  270  60 31   6.5   3.6 | -18.9  -2.0  275  58 30   6.3   3.5
 18500 -18.0  -0.4  270  58 30   5.9   3.2 | -17.9  -0.2  270  55 28   4.2   2.3
 18000 -17.2   1.0  270  54 28   5.0   2.8 | -17.7   0.1  270  50 26   1.2   0.6
 17500 -16.5   2.3  265  49 25   4.9   2.7 | -17.6   0.3  265  45 23   0.5   0.3
 17000 -15.7   3.7  265  44 23   7.0   3.8 | -17.0   1.4  265  40 21   7.8   4.3
 16500 -14.7   5.5  265  38 20   6.8   3.8 | -16.0   3.2  260  36 18   7.2   3.9
 16000 -13.7   7.3  265  33 17   7.3   4.0 | -15.0   5.0  255  31 16   8.3   4.5
 15500 -12.6   9.3  265  30 15   7.5   4.1 | -13.7   7.3  260  28 14   8.6   4.7
 15000 -11.6  11.1  265  27 14   7.8   4.3 | -12.5   9.5  260  24 13   8.0   4.4
 14500 -10.4  13.3  260  24 13   8.1   4.5 | -10.9  12.4  265  22 11   6.9   3.8
 14000  -8.6  16.5  260  21 11   7.6   4.2 |  -9.9  14.2  265  20 10   7.8   4.3
 13500  -7.6  18.3  255  18  9   7.5   4.1 |  -8.7  16.3  265  19 10   8.1   4.4
 13000  -6.5  20.3  250  15  8   7.2   4.0 |  -7.5  18.5  265  17  9   8.3   4.5
 12500  -5.5  22.1  240  13  7   7.0   3.9 |  -6.3  20.7  270  15  8   8.8   4.8
 12000  -4.4  24.1  230  11  5   7.3   4.0 |  -5.3  22.5  275  13  7   5.5   3.0
 11750  -3.9  25.0  230   9  5   6.5   3.6 |  -4.8  23.4  280  12  6   7.2   3.9
 11500  -3.4  25.9  225   8  4   6.3   3.4 |  -4.3  24.3  285  11  6   6.7   3.7
 11250  -2.9  26.8  220   7  4   8.1   4.4 |  -3.8  25.2  290  11  5   7.0   3.8
 11000  -2.3  27.9  215   6  3   8.7   4.8 |  -3.3  26.1  300  11  6   7.1   3.9
 10750  -1.7  28.9  205   5  3   7.2   3.9 |  -2.8  27.0  310  11  5   6.9   3.8
 10500  -1.2  29.8  195   4  2   7.7   4.2 |  -2.3  27.9  315  10  5   7.1   3.9
 10250  -0.6  30.9  175   3  2   7.2   3.9 |  -1.8  28.8  325  11  5   6.5   3.6
 10000  -0.1  31.8  145   3  1   7.5   4.1 |  -1.3  29.7  335  11  6   5.4   3.0
  9750   0.5  32.9  125   3  1   9.3   5.1 |  -0.9  30.4  340  12  6   6.1   3.3
  9500   1.2  34.2  110   4  2  10.0   5.5 |  -0.5  31.1  345  12  6   7.0   3.9
  9250   1.9  35.4  100   4  2   9.7   5.3 |   0.0  32.0  350  12  6   6.5   3.6
  9000   2.7  36.9  090   5  3   9.3   5.1 |   0.5  32.9  360  13  7   5.6   3.0
  8750   3.4  38.1  090   5  3   9.8   5.4 |   0.9  33.6  005  13  7   7.0   3.8
  8500   4.1  39.4  090   5  3  10.4   5.7 |   1.5  34.7  010  13  7   8.4   4.6
  8250   4.9  40.8  085   6  3  10.1   5.5 |   2.1  35.8  015  13  7   8.1   4.5
  8000   5.6  42.1  085   6  3  10.1   5.5 |   2.7  36.9  020  12  6   8.3   4.6
  7750   6.4  43.5  080   6  3   9.4   5.2 |   3.3  37.9  025  12  6   8.5   4.7
  7500   7.0  44.6  080   6  3   8.5   4.7 |   3.9  39.0  025  11  5   7.8   4.3
  7250   7.7  45.9  080   6  3   8.9   4.9 |   4.4  39.9  030  10  5   5.2   2.9
  7000   8.3  46.9  080   6  3   9.5   5.2 |   4.7  40.5  030   9  5   3.1   1.7
  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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