Soaring Guidance
Issued by NWS Pueblo, CO

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628
UXUS97 KPUB 131350
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0650 MST Monday, November 13, 2017

This forecast is for Monday, November 13, 2017:

If the trigger temperature of 55.9 F/13.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 986 ft/min (5.0 m/s)
   Maximum height of thermals.................. 18373 ft MSL (10798 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 0945 MST
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................. 15712 ft MSL (8137 ft AGL)
Thermal soaring outlook for Tuesday 11/14...... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:40:30 / 16:46:42 MST
Total possible sunshine........... 10 hr 6 min 12 sec (606 min 12 sec)
Altitude of sun at 11:43:36 MST... 32.73 degrees

Upper air data from numerical model forecast valid on 11/13/2017 at 0500 MST

Freezing level.................. 12155 ft MSL (4580 ft AGL)
Convective condensation level... 19396 ft MSL (11821 ft AGL)
Lifted condensation level....... 19079 ft MSL (11504 ft AGL)
Lifted index.................... +3.0
K index......................... +14.2

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   36   19   2.5   1.4      M     M       M      M    M
 45000  -60.7 -77.3   280   46   24   1.0   0.5      M     M       M      M    M
 40000  -59.3 -74.7   285   46   24   0.9   0.5      M     M       M      M    M
 38000  -55.5 -67.9   280   44   22   7.0   3.8      M     M       M      M    M
 36000  -51.3 -60.3   280   41   21   7.0   3.8      M     M       M      M    M
 34000  -47.0 -52.6   280   37   19   7.5   4.1      M     M       M      M    M
 32000  -42.5 -44.5   280   33   17   7.5   4.1      M     M       M      M    M
 30000  -37.8 -36.0   280   30   15   7.9   4.4   31.2  88.1     9.1      M    M
 29000  -35.4 -31.7   275   28   14   7.9   4.4   30.5  86.8     8.6      M    M
 28000  -33.0 -27.4   275   26   13   7.9   4.4   29.9  85.7     8.2      M    M
 27000  -30.7 -23.3   275   25   13   7.7   4.2   29.1  84.5     7.8      M    M
 26000  -28.4 -19.1   275   24   12   7.7   4.2   28.3  82.9     7.2      M    M
 25000  -26.1 -15.0   275   23   12   7.7   4.2   27.6  81.6     6.7      M    M
 24000  -23.9 -11.0   270   22   11   6.5   3.5   26.8  80.2     6.0      M    M
 23000  -21.9  -7.4   275   21   11   6.6   3.6   25.6  78.0     5.1      M    M
 22000  -19.5  -3.1   275   20   10   6.7   3.7   24.3  75.7     4.0      M    M
 21000  -17.7   0.1   275   19   10   6.0   3.3   23.0  73.4     2.9      M    M
 20000  -15.9   3.4   280   17    9   6.1   3.3   21.7  71.1     1.7      M    M
 19500  -15.0   5.0   280   16    8   6.1   3.3   21.1  70.0     1.2      M    M
 19000  -14.1   6.6   285   16    8   6.0   3.3   20.5  68.9     0.7      M    M
 18500  -13.2   8.2   285   15    8   6.0   3.3   19.9  67.8     0.1      M    M
 18000  -12.3   9.9   290   14    7   6.0   3.3   19.2  66.6    -0.5    950  4.8
 17500  -11.5  11.3   290   13    7   6.2   3.4   18.6  65.5    -1.1    908  4.6
 17000  -10.5  13.1   295   12    6   6.2   3.4   18.0  64.4    -1.7    866  4.4
 16500   -9.6  14.7   295   12    6   6.4   3.5   17.4  63.4    -2.2    824  4.2
 16000   -8.7  16.3   295   11    6   6.6   3.6   16.9  62.4    -2.7    780  4.0
 15500   -7.7  18.1   300   10    5   6.7   3.7   16.4  61.5    -3.2    737  3.7
 15000   -6.7  19.9   300   10    5   6.9   3.8   15.9  60.6    -3.7    691  3.5
 14500   -5.7  21.7   300   10    5   7.0   3.8   15.4  59.8    -4.2    646  3.3
 14000   -4.5  23.9   300   10    5   8.2   4.5   15.1  59.2    -4.5    597  3.0
 13500   -3.3  26.1   300   10    5   8.2   4.5   14.8  58.7    -4.8    546  2.8
 13000   -2.1  28.2   295   10    5   7.4   4.1   14.6  58.2    -5.1    495  2.5
 12500   -0.9  30.4   295   10    5   9.0   4.9   14.3  57.7    -5.4    444  2.3
 12000    0.3  32.5   295   10    5   7.8   4.3   14.1  57.3    -5.6    392  2.0
 11750    0.9  33.6   295   10    5   7.4   4.0   13.9  57.0    -5.8    367  1.9
 11500    1.5  34.7   295   10    5   9.0   5.0   13.8  56.8    -5.9    342  1.7
 11250    2.2  36.0   295   10    5   9.3   5.1   13.8  56.8    -5.9    312  1.6
 11000    2.9  37.2   290   11    5   7.7   4.2   13.6  56.5    -6.1    286  1.5
 10750    3.4  38.1   290   11    6   7.2   3.9   13.5  56.2    -6.3    261  1.3
 10500    4.0  39.2   290   11    6   9.9   5.4   13.3  56.0    -6.4    237  1.2
 10250    4.9  40.8   290   11    6  12.6   6.9   13.5  56.3    -6.2    202  1.0
 10000    5.8  42.4   295   11    5  10.2   5.6   13.6  56.5    -6.1    168  0.9
  9750    6.5  43.7   295   11    6   9.1   5.0   13.6  56.5    -6.2    139  0.7
  9500    7.2  45.0   295   11    6   9.6   5.2   13.6  56.4    -6.2    111  0.6
  9250    7.9  46.2   295   11    6   7.1   3.9   13.5  56.3    -6.3     83  0.4
  9000    8.4  47.1   295   11    6   6.7   3.7   13.2  55.8    -6.6     62  0.3
  8750    9.0  48.2   295   11    5   9.0   4.9   13.1  55.6    -6.7     36  0.2
  8500    9.6  49.3   295   10    5   6.6   3.6   13.0  55.4    -6.8     10  0.1
  8250    9.9  49.8   295   10    5   0.2   0.1   12.5  54.6    -7.3      M    M
  8000    9.2  48.6   290    9    4 -23.8 -13.1   11.1  52.0    -8.7      7  0.0
  7750    6.1  43.0   285    6    3 -54.6 -30.0    7.3  45.1   -12.5     92  0.5
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           11/13/2017 at 0800 MST          |       11/13/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +2.2        | CAPE...     0.0    LI...       +3.5
CINH...     0.0    K Index... +12.9        | CINH...     0.0    K Index...  +2.2
                                           |
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 -64.3 -83.7  275  39 20   0.6   0.3 | -64.1 -83.4  310  53 27  -0.4  -0.2
 45000 -63.1 -81.6  280  48 25   2.9   1.6 | -64.2 -83.6  315  68 35   2.7   1.5
 40000 -58.5 -73.3  285  51 26   3.0   1.6 | -59.9 -75.8  320  73 38   3.2   1.7
 38000 -54.8 -66.6  285  47 24   6.4   3.5 | -55.6 -68.1  315  65 34   7.6   4.2
 36000 -51.0 -59.8  285  43 22   6.4   3.5 | -51.0 -59.8  310  57 29   7.6   4.2
 34000 -46.8 -52.2  280  40 21   7.5   4.1 | -46.6 -51.9  310  52 27   7.3   4.0
 32000 -42.2 -44.0  280  38 20   7.6   4.1 | -42.2 -44.0  315  51 26   7.3   4.0
 30000 -37.7 -35.9  280  35 18   7.5   4.1 | -37.9 -36.2  320  49 25   7.1   3.9
 29000 -35.4 -31.7  280  33 17   7.5   4.1 | -35.7 -32.3  320  49 25   7.1   3.9
 28000 -33.2 -27.8  275  31 16   7.5   4.1 | -33.6 -28.5  325  49 25   7.1   3.9
 27000 -30.9 -23.6  275  30 15   7.2   4.0 | -31.5 -24.7  325  46 24   7.1   3.9
 26000 -28.8 -19.8  275  28 14   7.2   4.0 | -29.3 -20.7  315  39 20   7.1   3.9
 25000 -26.6 -15.9  275  26 13   7.3   4.0 | -27.2 -17.0  310  33 17   7.1   3.9
 24000 -24.0 -11.2  275  24 12   6.5   3.6 | -25.1 -13.2  310  31 16   7.5   4.1
 23000 -22.1  -7.8  275  22 11   6.5   3.6 | -22.3  -8.1  330  43 22   7.4   4.1
 22000 -20.1  -4.2  275  20 10   6.6   3.6 | -20.1  -4.2  340  55 28   7.5   4.1
 21000 -18.3  -0.9  280  18  9   5.9   3.3 | -17.9  -0.2  345  69 36   7.0   3.9
 20000 -16.6   2.1  280  15  8   6.0   3.3 | -15.8   3.6  345  84 43   7.0   3.9
 19500 -15.7   3.7  285  14  7   6.0   3.3 | -14.8   5.4  350  91 47   7.0   3.9
 19000 -14.8   5.4  290  13  7   6.3   3.5 | -13.7   7.3  350  99 51   7.1   3.9
 18500 -13.8   7.2  290  13  7   6.6   3.6 | -12.7   9.1  350 108 55   7.1   3.9
 18000 -12.9   8.8  295  12  6   6.6   3.6 | -11.6  11.1  350 116 60   7.1   3.9
 17500 -11.9  10.6  300  12  6   7.4   4.0 | -10.6  12.9  355 125 64   6.8   3.8
 17000 -10.8  12.6  300  12  6   7.3   4.0 |  -9.6  14.7  355 133 69   6.9   3.8
 16500  -9.7  14.5  305  12  6   7.4   4.0 |  -8.6  16.5  355 142 73   6.7   3.7
 16000  -8.6  16.5  310  12  6   7.4   4.1 |  -7.6  18.3  355 152 78   6.7   3.7
 15500  -7.5  18.5  310  12  6   7.5   4.1 |  -6.6  20.1  355 161 83   7.2   3.9
 15000  -6.3  20.7  310  12  6   7.9   4.3 |  -5.4  22.3  355 167 86   8.0   4.4
 14500  -5.2  22.6  310  13  7   7.8   4.3 |  -4.3  24.3  355 173 89   8.0   4.4
 14000  -4.1  24.6  310  13  7   6.9   3.8 |  -3.2  26.2  355 180 93   7.3   4.0
 13500  -3.0  26.6  305  14  7   6.8   3.8 |  -2.1  28.2  355 187 96   7.3   4.0
 13000  -1.9  28.6  305  14  7   8.3   4.6 |  -0.9  30.4  360 188 97   8.4   4.6
 12500  -0.8  30.6  305  13  7   6.8   3.7 |   0.2  32.4  360 186 96   7.3   4.0
 12000   0.4  32.7  305  13  7   9.1   5.0 |   1.3  34.3  360 177 91   6.8   3.8
 11750   1.1  34.0  305  12  6   9.5   5.2 |   1.8  35.2  360 167 86   7.2   3.9
 11500   1.8  35.2  305  12  6   7.6   4.2 |   2.3  36.1  360 157 81   6.0   3.3
 11250   2.3  36.1  305  11  6   7.1   3.9 |   2.7  36.9  360 148 76   7.1   3.9
 11000   2.9  37.2  305  11  6   9.0   4.9 |   3.4  38.1  360 146 75   9.3   5.1
 10750   3.6  38.5  305  11  6   9.1   5.0 |   4.1  39.4  360 145 75   9.3   5.1
 10500   4.2  39.6  305  11  6   8.3   4.6 |   4.8  40.6  355 145 74   8.3   4.5
 10250   4.8  40.6  305  10  5   7.4   4.0 |   5.3  41.5  355 143 74   7.4   4.1
 10000   5.4  41.7  305  10  5   8.3   4.5 |   5.9  42.6  355 139 72   8.2   4.5
  9750   6.0  42.8  305   9  5   8.7   4.8 |   6.6  43.9  355 136 70   8.3   4.6
  9500   6.7  44.1  300   9  5   8.9   4.9 |   7.2  45.0  355 133 68   8.1   4.5
  9250   7.3  45.1  300   9  5   6.3   3.5 |   7.8  46.0  355 127 66   7.1   3.9
  9000   7.7  45.9  300   9  4   5.2   2.9 |   8.3  46.9  355 105 54   8.1   4.4
  8750   8.2  46.8  295   8  4   7.0   3.8 |   8.9  48.0  355  82 42   9.4   5.1
  8500   8.6  47.5  295   8  4   5.8   3.2 |   9.6  49.3  355  60 31   9.1   5.0
  8250   9.0  48.2  290   8  4   3.0   1.6 |  10.3  50.5  355  46 23   9.6   5.3
  8000   8.8  47.8  290   8  4 -10.8  -5.9 |  11.1  52.0  355  42 22  13.5   7.4
  7750   7.3  45.1  285   6  3 -29.3 -16.1 |  12.3  54.1  350  28 14  19.2  10.6
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           11/13/2017 at 1400 MST          |       11/13/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +3.8        | CAPE...     0.0    LI...       +3.8
CINH...     0.0    K Index...  -0.4        | CINH...     0.0    K Index...  +0.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.8 -84.6  310  56 29  -0.3  -0.2 | -65.6 -86.1  315  64 33   0.3   0.2
 45000 -64.7 -84.5  315  68 35   3.2   1.8 | -64.6 -84.3  315  68 35   3.5   1.9
 40000 -59.4 -74.9  310  59 30   4.3   2.4 | -59.2 -74.6  305  59 30   3.3   1.8
 38000 -55.0 -67.0  310  57 29   7.6   4.2 | -54.7 -66.5  310  58 30   7.1   3.9
 36000 -50.4 -58.7  310  55 28   7.6   4.2 | -50.4 -58.7  315  58 30   7.1   3.9
 34000 -46.0 -50.8  310  53 27   7.1   3.9 | -46.0 -50.8  320  58 30   7.6   4.2
 32000 -41.7 -43.1  315  52 27   7.1   3.9 | -41.4 -42.5  325  59 30   7.6   4.2
 30000 -37.4 -35.3  320  50 26   7.2   3.9 | -37.0 -34.6  330  55 28   7.0   3.8
 29000 -35.3 -31.5  325  48 25   7.2   3.9 | -34.9 -30.8  330  51 26   7.0   3.8
 28000 -33.1 -27.6  325  47 24   7.2   3.9 | -32.8 -27.0  330  47 24   7.0   3.9
 27000 -31.0 -23.8  325  46 24   7.2   3.9 | -30.7 -23.3  325  42 22   7.3   4.0
 26000 -28.8 -19.8  325  45 23   7.2   3.9 | -28.5 -19.3  320  37 19   7.3   4.0
 25000 -26.7 -16.1  325  43 22   7.2   3.9 | -26.3 -15.3  315  32 16   7.3   4.0
 24000 -24.5 -12.1  330  45 23   7.8   4.3 | -24.1 -11.4  315  31 16   7.4   4.1
 23000 -21.6  -6.9  335  56 29   7.8   4.3 | -21.9  -7.4  330  42 22   7.4   4.1
 22000 -19.2  -2.6  340  65 34   7.8   4.3 | -19.1  -2.4  340  58 30   7.5   4.1
 21000 -17.1   1.2  345  76 39   7.1   3.9 | -16.9   1.6  345  68 35   7.1   3.9
 20000 -14.9   5.2  350  87 45   7.1   3.9 | -14.8   5.4  350  77 40   7.1   3.9
 19500 -13.9   7.0  350  92 47   7.1   3.9 | -13.7   7.3  350  82 42   7.1   3.9
 19000 -12.8   9.0  350  98 50   7.2   4.0 | -12.7   9.1  350  86 44   7.1   3.9
 18500 -11.7  10.9  350 102 52   7.3   4.0 | -11.6  11.1  350  90 46   7.1   3.9
 18000 -10.6  12.9  350 106 54   7.3   4.0 | -10.5  13.1  350  94 49   7.1   3.9
 17500  -9.5  14.9  350 109 56   7.2   3.9 |  -9.5  14.9  350  96 49   6.6   3.6
 17000  -8.5  16.7  350 113 58   7.2   3.9 |  -8.5  16.7  350  95 49   6.6   3.6
 16500  -7.4  18.7  355 116 60   7.0   3.8 |  -7.6  18.3  350  94 48   6.3   3.5
 16000  -6.4  20.5  355 121 62   6.9   3.8 |  -6.6  20.1  350  89 46   6.2   3.4
 15500  -5.3  22.5  355 125 64   6.6   3.6 |  -5.7  21.7  350  84 43   6.2   3.4
 15000  -4.4  24.1  355 124 64   6.0   3.3 |  -4.8  23.4  350  75 39   6.1   3.3
 14500  -3.5  25.7  355 122 63   6.0   3.3 |  -3.9  25.0  350  66 34   6.1   3.4
 14000  -2.6  27.3  355 115 59   6.1   3.4 |  -3.0  26.6  345  43 22   6.6   3.6
 13500  -1.7  28.9  355 105 54   6.1   3.3 |  -2.1  28.2  315  15  8   6.4   3.5
 13000  -0.8  30.6  355  89 46   7.5   4.1 |  -0.9  30.4  200  23 12   9.8   5.4
 12500   0.2  32.4  355  65 33   7.1   3.9 |   0.3  32.5  190  48 25   8.2   4.5
 12000   1.3  34.3  350  33 17   8.2   4.5 |   1.6  34.9  185  61 32   8.9   4.9
 11750   1.9  35.4  335  13  7   7.8   4.3 |   2.3  36.1  185  66 34   8.5   4.7
 11500   2.5  36.5  210  10  5  10.1   5.5 |   2.9  37.2  185  70 36  10.5   5.8
 11250   3.3  37.9  190  25 13  10.9   6.0 |   3.8  38.8  185  71 37  10.4   5.7
 11000   4.0  39.2  185  36 18   8.9   4.9 |   4.4  39.9  185  75 39   8.0   4.4
 10750   4.7  40.5  185  45 23   8.8   4.8 |   5.0  41.0  185  81 41   7.5   4.1
 10500   5.4  41.7  185  54 28   9.6   5.2 |   5.6  42.1  185  86 44   9.5   5.2
 10250   6.2  43.2  185  61 32  10.9   6.0 |   6.4  43.5  185  89 46  11.7   6.4
 10000   7.0  44.6  185  65 34  10.6   5.8 |   7.2  45.0  185  95 49   9.9   5.4
  9750   7.7  45.9  180  71 36  10.0   5.5 |   7.9  46.2  180 104 53   8.7   4.8
  9500   8.5  47.3  180  76 39  10.8   6.0 |   8.6  47.5  180 112 58   9.7   5.3
  9250   9.3  48.7  180  81 41   8.1   4.5 |   9.3  48.7  180 120 62   7.2   3.9
  9000   9.8  49.6  180  86 44   8.3   4.6 |   9.7  49.5  180 136 70   7.1   3.9
  8750  10.6  51.1  180  89 46  11.2   6.1 |  10.4  50.7  180 149 76   9.3   5.1
  8500  11.4  52.5  180  92 48  10.4   5.7 |  11.1  52.0  180 161 83   8.8   4.8
  8250  12.2  54.0  180  96 49  10.2   5.6 |  11.6  52.9  180 173 89   5.6   3.1
  8000  13.0  55.4  180 103 53  12.8   7.0 |  11.8  53.2  180 183 94  -2.3  -1.2
  7750  14.1  57.4  180 112 58  17.7   9.7 |  11.3  52.3  180 184 95  -7.9  -4.3
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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).  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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