Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 051207
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0507 MST Monday, December 5, 2016

This forecast is for Monday, December 5, 2016:

If the trigger temperature of 50.8 F/10.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 201 ft/min (1.0 m/s)
   Maximum height of thermals.................. 9536 ft MSL (2366 ft AGL)

Forecast maximum temperature................... 47.0 F/8.8 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................. 8271 ft MSL (1101 ft AGL)
Thermal soaring outlook for Tuesday 12/06...... Poor

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

Remarks...

Sunrise/Sunset.................... 07:03:00 / 16:36:50 MST
Total possible sunshine........... 9 hr 33 min 50 sec (573 min 50 sec)
Altitude of sun at 11:50:01 MST... 28.62 degrees

Upper air data from numerical model forecast valid on 12/05/2016 at 0500 MST

Freezing level.................. 7531 ft MSL (361 ft AGL)
Additional freezing level....... 10207 ft MSL (3037 ft AGL)
Convective condensation level... 19318 ft MSL (12148 ft AGL)
Lifted condensation level....... 14901 ft MSL (7732 ft AGL)
Lifted index.................... +7.4
K index......................... -2.1

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  -61.6 -78.9   265   62   32   2.1   1.2      M     M       M      M    M
 45000  -58.5 -73.3   265   77   40   2.2   1.2      M     M       M      M    M
 40000  -59.3 -74.7   275   71   36  -0.8  -0.4      M     M       M      M    M
 38000  -58.9 -74.0   280   69   35   2.9   1.6      M     M       M      M    M
 36000  -57.2 -71.0   275   69   35   2.9   1.6      M     M       M      M    M
 34000  -55.2 -67.4   270   69   35   8.3   4.6      M     M       M      M    M
 32000  -49.9 -57.8   265   66   34   8.8   4.8      M     M       M      M    M
 30000  -44.6 -48.3   260   63   32   8.9   4.9   25.1  77.1    12.8      M    M
 29000  -42.0 -43.6   260   60   31   8.8   4.8   24.6  76.2    12.6      M    M
 28000  -39.4 -38.9   265   58   30   8.8   4.8   24.2  75.5    12.5      M    M
 27000  -36.7 -34.1   265   56   29   8.9   4.9   23.9  75.1    12.4      M    M
 26000  -34.3 -29.7   265   54   28   7.9   4.3   23.3  73.9    12.0      M    M
 25000  -31.9 -25.4   265   52   27   7.9   4.3   22.6  72.6    11.6      M    M
 24000  -29.0 -20.2   265   50   26   8.0   4.4   21.8  71.3    11.1      M    M
 23000  -26.3 -15.3   265   49   25   9.2   5.0   21.5  70.7    11.0      M    M
 22000  -23.6 -10.5   260   48   24   9.2   5.0   21.3  70.3    10.9      M    M
 21000  -20.8  -5.4   260   46   24   8.9   4.9   21.1  70.1    10.9      M    M
 20000  -18.3  -0.9   265   46   24   8.4   4.6   20.6  69.1    10.6      M    M
 19500  -17.1   1.2   265   46   24   8.4   4.6   20.4  68.7    10.4      M    M
 19000  -15.8   3.6   265   46   24   8.4   4.6   20.1  68.3    10.3      M    M
 18500  -14.6   5.7   270   46   23   8.3   4.5   20.0  67.9    10.2      M    M
 18000  -13.5   7.7   270   46   24   6.7   3.7   19.6  67.2     9.9      M    M
 17500  -12.5   9.5   275   46   24   6.8   3.7   19.1  66.3     9.5      M    M
 17000  -11.5  11.3   280   46   24   6.4   3.5   18.6  65.4     9.1      M    M
 16500  -10.6  12.9   280   45   23   6.3   3.4   18.0  64.3     8.6      M    M
 16000   -9.6  14.7   280   44   23   6.3   3.5   17.4  63.3     8.1      M    M
 15500   -8.7  16.3   280   42   21   6.6   3.6   16.8  62.3     7.6      M    M
 15000   -7.7  18.1   285   39   20   6.6   3.6   16.3  61.4     7.2      M    M
 14500   -6.8  19.8   285   40   20   5.9   3.2   15.8  60.4     6.7      M    M
 14000   -5.9  21.4   290   45   23   6.0   3.3   15.1  59.3     6.1      M    M
 13500   -5.1  22.8   290   48   25   5.1   2.8   14.5  58.1     5.5      M    M
 13000   -4.3  24.3   290   48   25   4.9   2.7   13.7  56.7     4.8      M    M
 12500   -3.6  25.5   295   48   25   6.2   3.4   13.0  55.3     4.1      M    M
 12000   -2.8  27.0   295   51   26   3.5   1.9   12.3  54.1     3.5      M    M
 11750   -2.6  27.3   295   52   27   2.9   1.6   11.8  53.2     3.0      M    M
 11500   -2.3  27.9   295   53   28   4.7   2.6   11.3  52.3     2.5      M    M
 11250   -1.9  28.6   295   53   27   6.3   3.5   11.0  51.7     2.2      M    M
 11000   -1.5  29.3   295   53   27   5.3   2.9   10.7  51.2     1.9      M    M
 10750   -1.1  30.0   295   52   27   4.2   2.3   10.3  50.5     1.5      M    M
 10500   -0.8  30.6   295   51   26   5.6   3.1    9.9  49.8     1.1      M    M
 10250   -0.3  31.5   295   49   25   7.0   3.8    9.6  49.3     0.9      M    M
 10000    0.2  32.4   295   47   24   6.6   3.6    9.4  48.9     0.7      M    M
  9750    1.1  34.0   295   42   22   5.2   2.9    8.9  48.0     0.2      M    M
  9500    1.4  34.5   295   39   20   3.9   2.1    8.5  47.2    -0.3    191  1.0
  9250    1.7  35.1   295   36   19   4.5   2.5    8.0  46.5    -0.7    174  0.9
  9000    2.1  35.8   295   34   17   3.3   1.8    7.6  45.7    -1.1    157  0.8
  8750    2.2  36.0   290   30   15  -0.1  -0.0    7.0  44.6    -1.7    146  0.7
  8500    2.1  35.8   290   26   13  -1.9  -1.0    6.2  43.1    -2.6    142  0.7
  8250    2.0  35.6   290   22   11  -0.2  -0.1    5.3  41.6    -3.4    138  0.7
  8000    1.9  35.4   285   17    9  -5.1  -2.8    4.5  40.1    -4.2    133  0.7
  7750    1.0  33.8   285   15    8 -19.2 -10.5    2.9  37.1    -5.9    153  0.8
  7500   -0.9  30.4   280    9    5 -28.0 -15.4    0.3  32.5    -8.5    201  1.0
  7250   -2.7  27.1   270    4    2 -16.7  -9.1   -2.3  27.9   -11.1    249  1.3
  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 * * * * * *

           12/05/2016 at 0800 MST          |       12/05/2016 at 1100 MST
                                           |
K index... -7.1  LI... +5.3                | K index... -7.6  LI... +3.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.0
                                           |
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 -61.0 -77.8  255  60 31   1.7   0.9 | -59.7 -75.5  250  61 32   1.3   0.7
 45000 -58.5 -73.3  260  79 40   1.7   0.9 | -57.6 -71.7  250  88 46   1.2   0.7
 40000 -58.4 -73.1  275  74 38  -0.1  -0.1 | -59.7 -75.5  260  74 38  -1.7  -0.9
 38000 -58.3 -72.9  275  71 36   1.2   0.6 | -59.9 -75.8  265  68 35   3.8   2.1
 36000 -57.4 -71.3  260  62 32   1.2   0.7 | -57.3 -71.1  260  64 33   3.8   2.1
 34000 -56.5 -69.7  245  59 30   6.8   3.7 | -55.0 -67.0  255  61 31   5.8   3.2
 32000 -51.1 -60.0  250  59 30   9.0   5.0 | -50.6 -59.1  260  62 32   7.3   4.0
 30000 -45.7 -50.3  250  58 30   9.7   5.3 | -46.2 -51.2  265  63 33   7.8   4.3
 29000 -42.8 -45.0  250  57 29   9.6   5.3 | -43.8 -46.8  265  63 32   7.9   4.4
 28000 -39.9 -39.8  250  56 29   9.6   5.3 | -41.5 -42.7  265  63 32   7.9   4.4
 27000 -37.0 -34.6  250  54 28   9.7   5.3 | -39.1 -38.4  270  63 32   7.9   4.3
 26000 -34.4 -29.9  255  52 27   8.4   4.6 | -36.5 -33.7  270  63 32   9.1   5.0
 25000 -31.9 -25.4  255  50 26   8.4   4.6 | -33.8 -28.8  265  62 32   9.1   5.0
 24000 -29.4 -20.9  260  48 25   8.3   4.6 | -31.1 -24.0  260  62 32   9.1   5.0
 23000 -26.3 -15.3  260  44 23   8.1   4.4 | -27.9 -18.2  260  61 31   8.0   4.4
 22000 -23.9 -11.0  260  40 21   8.1   4.4 | -25.6 -14.1  260  59 30   8.0   4.4
 21000 -21.5  -6.7  260  36 19   7.9   4.3 | -23.2  -9.8  265  57 29   8.0   4.4
 20000 -19.4  -2.9  265  34 17   7.1   3.9 | -20.8  -5.4  265  55 28   8.0   4.4
 19500 -18.3  -0.9  265  33 17   7.2   3.9 | -19.6  -3.3  265  54 28   8.0   4.4
 19000 -17.2   1.0  270  32 17   7.2   3.9 | -18.4  -1.1  265  53 27   8.1   4.4
 18500 -16.2   2.8  275  32 16   7.2   3.9 | -17.2   1.0  270  52 27   8.4   4.6
 18000 -15.1   4.8  280  32 16   7.1   3.9 | -16.2   2.8  270  51 26   4.9   2.7
 17500 -14.0   6.8  285  32 17   7.1   3.9 | -15.4   4.3  275  52 27   5.3   2.9
 17000 -13.0   8.6  290  34 17   6.8   3.7 | -14.6   5.7  275  53 27   6.7   3.7
 16500 -12.0  10.4  290  35 18   6.5   3.6 | -13.4   7.9  275  50 26   7.7   4.2
 16000 -11.0  12.2  290  37 19   6.5   3.5 | -12.3   9.9  275  48 25   7.9   4.3
 15500 -10.2  13.6  295  40 21   5.5   3.0 | -11.0  12.2  275  45 23   8.7   4.8
 15000  -9.3  15.3  295  44 22   5.7   3.1 |  -9.7  14.5  275  43 22   8.9   4.9
 14500  -8.6  16.5  295  48 25   4.1   2.2 |  -8.6  16.5  275  42 22   6.5   3.6
 14000  -8.0  17.6  295  52 27   4.1   2.2 |  -7.6  18.3  280  42 22   6.7   3.7
 13500  -7.4  18.7  290  56 29   4.0   2.2 |  -6.7  19.9  285  43 22   2.7   1.5
 13000  -6.9  19.6  295  59 30   4.0   2.2 |  -6.5  20.3  285  45 23   1.6   0.9
 12500  -6.3  20.7  295  61 31   5.1   2.8 |  -6.3  20.7  290  48 25   0.3   0.2
 12000  -5.5  22.1  295  59 30   3.9   2.1 |  -6.5  20.3  290  45 23  -0.4  -0.2
 11750  -5.3  22.5  295  57 30   3.1   1.7 |  -6.6  20.1  290  44 23  -1.4  -0.7
 11500  -5.0  23.0  295  56 29   4.1   2.3 |  -6.6  20.1  295  43 22   2.6   1.4
 11250  -4.7  23.5  295  53 27   5.0   2.8 |  -6.2  20.8  295  40 21   6.2   3.4
 11000  -4.4  24.1  295  50 26   4.7   2.6 |  -5.9  21.4  295  37 19   5.6   3.1
 10750  -4.0  24.8  295  47 24   3.9   2.2 |  -5.4  22.3  300  34 17   6.2   3.4
 10500  -3.7  25.3  300  44 22   5.4   3.0 |  -4.9  23.2  300  31 16   7.9   4.3
 10250  -3.2  26.2  300  41 21   6.9   3.8 |  -4.3  24.3  300  29 15   9.3   5.1
 10000  -2.7  27.1  300  38 20   6.8   3.7 |  -3.6  25.5  300  27 14   8.8   4.8
  9750  -2.3  27.9  300  35 18   5.8   3.2 |  -3.0  26.6  305  25 13   9.2   5.0
  9500  -1.4  29.5  300  30 15   6.6   3.6 |  -1.6  29.1  305  22 11   9.5   5.2
  9250  -0.9  30.4  300  27 14   6.4   3.5 |  -0.9  30.4  305  21 11   9.4   5.2
  9000  -0.5  31.1  305  24 13   6.1   3.4 |  -0.2  31.6  310  19 10   9.6   5.2
  8750  -0.0  32.0  305  21 11   5.8   3.2 |   0.6  33.1  310  18  9   9.8   5.4
  8500   0.4  32.7  305  18  9   5.7   3.1 |   1.3  34.3  310  17  9   9.9   5.5
  8250   0.8  33.4  305  16  8   6.7   3.7 |   2.0  35.6  310  16  8   9.8   5.4
  8000   1.3  34.3  310  13  7   3.0   1.6 |   2.8  37.0  310  15  8  10.2   5.6
  7750   1.0  33.8  305  11  6 -10.3  -5.6 |   3.6  38.5  310  14  7  13.2   7.2
  7500  -0.2  31.6  305   7  4 -20.9 -11.5 |   4.7  40.5  310  12  6  17.1   9.4
  7250  -1.4  29.5  290   4  2  -5.4  -2.9 |   5.9  42.6  315  10  5  10.5   5.8
  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

           12/05/2016 at 1400 MST          |       12/05/2016 at 1700 MST
                                           |
K index... -24.1  LI... +2.5               | K index... -32.5  LI... +2.5
CAPE... 0.0  CIN... -0.0                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.2 -74.6  250  64 33   1.4   0.8 | -58.0 -72.4  250  59 30   0.1   0.0
 45000 -57.1 -70.8  250  93 48   1.4   0.8 | -57.9 -72.2  250  86 44   0.1   0.0
 40000 -58.6 -73.5  265  76 39  -1.3  -0.7 | -58.8 -73.8  265  69 35  -0.7  -0.4
 38000 -58.8 -73.8  270  70 36   2.4   1.3 | -58.8 -73.8  270  63 33   2.8   1.5
 36000 -57.3 -71.1  260  70 36   2.5   1.4 | -57.1 -70.8  265  73 37   2.9   1.6
 34000 -55.8 -68.4  255  71 37   2.5   1.4 | -55.4 -67.7  260  82 42   2.5   1.4
 32000 -51.7 -61.1  255  69 35   7.3   4.0 | -52.0 -61.6  260  80 41   6.1   3.3
 30000 -47.3 -53.1  260  67 34   7.6   4.2 | -48.3 -54.9  265  77 39   6.3   3.5
 29000 -44.9 -48.8  260  68 35   8.4   4.6 | -45.8 -50.4  265  75 38   8.8   4.8
 28000 -42.4 -44.3  265  69 36   8.4   4.6 | -43.2 -45.8  265  73 37   8.7   4.8
 27000 -39.2 -38.6  265  71 36   8.5   4.6 | -40.6 -41.1  265  71 36   8.7   4.8
 26000 -36.9 -34.4  270  69 36   7.5   4.1 | -38.2 -36.8  270  69 35   6.6   3.6
 25000 -34.6 -30.3  270  66 34   7.5   4.1 | -36.2 -33.2  270  67 34   6.7   3.7
 24000 -32.3 -26.1  275  64 33   7.5   4.1 | -33.7 -28.7  275  65 33   6.7   3.7
 23000 -30.2 -22.4  275  62 32   6.8   3.7 | -31.8 -25.2  280  63 32   6.2   3.4
 22000 -28.1 -18.6  275  60 31   6.8   3.7 | -30.0 -22.0  280  59 31   6.1   3.4
 21000 -26.1 -15.0  275  58 30   6.8   3.7 | -28.1 -18.6  280  56 29   6.0   3.3
 20000 -23.9 -11.0  275  56 29   7.2   4.0 | -26.0 -14.8  275  53 27   7.4   4.0
 19500 -22.9  -9.2  275  55 28   7.2   4.0 | -24.9 -12.8  275  52 27   7.4   4.0
 19000 -21.8  -7.2  275  54 28   7.2   4.0 | -23.8 -10.8  275  51 26   7.3   4.0
 18500 -20.7  -5.3  275  53 27   7.1   3.9 | -22.7  -8.9  270  50 26   7.1   3.9
 18000 -19.5  -3.1  275  52 27   9.5   5.2 | -21.5  -6.7  270  49 25  10.0   5.5
 17500 -18.0  -0.4  270  50 26   9.6   5.3 | -19.9  -3.8  265  49 25  10.2   5.6
 17000 -16.6   2.1  270  48 25   9.6   5.3 | -18.4  -1.1  265  48 25   9.9   5.5
 16500 -15.1   4.8  270  47 24   9.6   5.2 | -17.0   1.4  265  48 25   9.6   5.3
 16000 -13.7   7.3  270  46 24   9.6   5.3 | -15.5   4.1  270  48 25   9.6   5.3
 15500 -12.4   9.7  270  46 24   8.3   4.5 | -14.3   6.3  270  48 25   7.5   4.1
 15000 -11.1  12.0  270  46 23   8.6   4.7 | -13.1   8.4  275  48 25   7.9   4.3
 14500 -10.0  14.0  270  45 23   5.1   2.8 | -12.1  10.2  275  48 25   4.6   2.5
 14000  -9.3  15.3  275  44 23   4.7   2.6 | -11.5  11.3  280  47 24   4.5   2.5
 13500  -8.7  16.3  275  43 22   1.7   0.9 | -10.8  12.6  285  45 23   3.6   2.0
 13000  -8.7  16.3  280  40 21   0.5   0.3 | -10.4  13.3  285  40 21   3.3   1.8
 12500  -8.7  16.3  285  38 19   1.3   0.7 |  -9.9  14.2  285  36 18   4.4   2.4
 12000  -8.4  16.9  285  31 16   3.4   1.9 |  -9.2  15.4  285  32 16   4.2   2.3
 11750  -8.2  17.2  285  27 14   2.9   1.6 |  -8.9  16.0  285  29 15   3.4   1.9
 11500  -8.0  17.6  290  23 12   6.8   3.7 |  -8.6  16.5  285  26 13   6.4   3.5
 11250  -7.2  19.0  290  23 12  11.0   6.0 |  -8.0  17.6  285  24 13   8.8   4.8
 11000  -6.5  20.3  290  23 12   9.4   5.1 |  -7.4  18.7  285  23 12   7.8   4.3
 10750  -5.8  21.6  290  22 11   8.2   4.5 |  -6.9  19.6  290  21 11   6.9   3.8
 10500  -5.2  22.6  290  21 11   9.1   5.0 |  -6.4  20.5  290  19 10   8.2   4.5
 10250  -3.7  25.3  290  20 10  10.3   5.7 |  -5.7  21.7  290  19 10   9.6   5.3
 10000  -2.9  26.8  290  19 10   9.3   5.1 |  -5.0  23.0  295  18  9   9.3   5.1
  9750  -2.3  27.9  290  19 10   9.0   4.9 |  -3.6  25.5  295  16  8   9.2   5.1
  9500  -1.6  29.1  290  18  9  10.0   5.5 |  -2.9  26.8  295  16  8   9.7   5.3
  9250  -0.8  30.6  295  18  9   9.5   5.2 |  -2.2  28.0  300  15  8   9.5   5.2
  9000  -0.1  31.8  295  18  9  10.5   5.7 |  -1.5  29.3  300  15  8   9.8   5.4
  8750   0.7  33.3  295  17  9  10.6   5.8 |  -0.8  30.6  300  14  7   9.8   5.4
  8500   1.5  34.7  295  17  9   9.8   5.4 |  -0.1  31.8  305  14  7   9.5   5.2
  8250   2.2  36.0  295  16  8  10.1   5.5 |   0.7  33.3  305  13  7   9.8   5.4
  8000   3.0  37.4  295  16  8   9.7   5.3 |   1.4  34.5  305  12  6   8.2   4.5
  7750   3.7  38.7  295  15  8  12.2   6.7 |   1.6  34.9  310  11  6  -2.9  -1.6
  7500   4.8  40.6  295  13  7  17.1   9.4 |   0.8  33.4  315   8  4 -16.9  -9.3
  7250   5.9  42.6  300  11  6   8.1   4.4 |   0.0  32.0  325   5  3   6.8   3.7
  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) 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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