Soaring Guidance
Issued by NWS Pueblo, CO

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354
UXUS97 KPUB 071118
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0418 MST Wednesday, December 7, 2016

This forecast is for Wednesday, December 7, 2016:

If the trigger temperature of 28.6 F/-1.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7171 ft MSL (0 ft AGL)

Forecast maximum temperature................... 11.0 F/-12.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Thursday 12/08..... Poor

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

Remarks...

Sunrise/Sunset.................... 07:04:45 / 16:36:49 MST
Total possible sunshine........... 9 hr 32 min 4 sec (572 min 4 sec)
Altitude of sun at 11:50:52 MST... 28.40 degrees

Upper air data from numerical model forecast valid on 12/07/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 13061 ft MSL (5890 ft AGL)
Lifted condensation level....... 8868 ft MSL (1697 ft AGL)
Lifted index.................... +19.9
K index......................... +3.3

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  -58.5 -73.3   270   59   31   3.5   1.9      M     M       M      M    M
 45000  -53.3 -63.9   265   66   34   3.5   1.9      M     M       M      M    M
 40000  -50.3 -58.5   275   81   42   1.8   1.0      M     M       M      M    M
 38000  -49.2 -56.6   275   88   45   1.2   0.6      M     M       M      M    M
 36000  -48.9 -56.0   275   95   49   0.5   0.3      M     M       M      M    M
 34000  -48.6 -55.5   275  102   52   0.5   0.3      M     M       M      M    M
 32000  -47.5 -53.5   275  107   55   2.3   1.3      M     M       M      M    M
 30000  -46.1 -51.0   275  111   57   2.3   1.3      M     M       M      M    M
 29000  -45.2 -49.4   275  112   58   4.7   2.6   24.3  75.7    27.6      M    M
 28000  -43.9 -47.0   275  112   58   4.5   2.5   22.1  71.8    26.2      M    M
 27000  -42.5 -44.5   275  112   58   4.5   2.5   20.1  68.3    25.0      M    M
 26000  -41.2 -42.2   275  112   58   4.6   2.5   18.3  65.0    23.9      M    M
 25000  -39.7 -39.5   275  107   55   4.9   2.7   16.4  61.5    22.6      M    M
 24000  -38.2 -36.8   275  102   52   4.9   2.7   14.6  58.3    21.4      M    M
 23000  -36.5 -33.7   275   95   49   3.0   1.6   12.5  54.4    20.0      M    M
 22000  -35.9 -32.6   270   86   45   2.0   1.1    9.5  49.2    17.8      M    M
 21000  -35.3 -31.5   270   78   40   2.0   1.1    6.8  44.3    15.7      M    M
 20000  -34.5 -30.1   265   71   36   4.6   2.5    4.4  39.9    13.8      M    M
 19500  -33.8 -28.8   265   66   34   4.5   2.4    3.4  38.2    13.1      M    M
 19000  -33.2 -27.8   265   62   32   4.5   2.4    2.5  36.5    12.3      M    M
 18500  -32.5 -26.5   270   58   30   4.5   2.5    1.6  34.9    11.6      M    M
 18000  -31.8 -25.2   270   54   28   5.1   2.8    0.8  33.4    10.9      M    M
 17500  -30.7 -23.3   270   49   25   8.8   4.8    0.4  32.7    10.6      M    M
 17000  -29.5 -21.1   270   44   22   8.5   4.7    0.2  32.3    10.5      M    M
 16500  -28.2 -18.8   275   39   20   9.1   5.0    0.0  32.0    10.4      M    M
 16000  -26.8 -16.2   275   35   18   9.1   5.0   -0.1  31.8    10.4      M    M
 15500  -25.5 -13.9   280   31   16   9.0   4.9   -0.2  31.7    10.3      M    M
 15000  -24.1 -11.4   280   29   15   9.0   4.9   -0.3  31.4    10.2      M    M
 14500  -22.8  -9.0   285   26   14   9.0   5.0   -0.4  31.2    10.2      M    M
 14000  -21.4  -6.5   285   25   13   9.1   5.0   -0.6  31.0    10.1      M    M
 13500  -20.1  -4.2   290   24   12   9.2   5.1   -0.7  30.8    10.1      M    M
 13000  -18.7  -1.7   290   23   12   9.4   5.1   -0.7  30.7    10.1      M    M
 12500  -17.3   0.9   290   22   11   9.3   5.1   -0.8  30.6    10.0      M    M
 12000  -16.0   3.2   295   22   11   9.0   4.9   -0.9  30.4    10.0      M    M
 11750  -15.3   4.5   295   21   11   9.1   5.0   -0.9  30.3    10.0      M    M
 11500  -14.7   5.5   295   21   11   7.0   3.9   -1.0  30.1     9.9      M    M
 11250  -14.3   6.3   300   21   11   4.8   2.6   -1.4  29.5     9.6      M    M
 11000  -13.9   7.0   300   20   11   4.4   2.4   -1.8  28.8     9.2      M    M
 10750  -13.6   7.5   305   20   10   5.9   3.3   -2.2  28.1     8.9      M    M
 10500  -13.2   8.2   305   20   10   1.7   0.9   -2.5  27.5     8.6      M    M
 10250  -13.3   8.1   310   20   10  -3.1  -1.7   -3.4  25.8     7.7      M    M
 10000  -13.5   7.7   310   19   10  -2.2  -1.2   -4.4  24.1     6.8      M    M
  9750  -13.7   7.3   315   19   10  -1.8  -1.0   -5.3  22.5     5.9      M    M
  9500  -14.2   6.4   325   19   10  -5.4  -3.0   -7.4  18.8     4.0      M    M
  9250  -14.6   5.7   330   18    9  -6.2  -3.4   -8.5  16.7     2.9      M    M
  9000  -15.0   5.0   340   18    9  -1.3  -0.7   -9.6  14.6     1.8      M    M
  8750  -14.7   5.5   345   16    8   5.9   3.2  -10.1  13.8     1.3      M    M
  8500  -14.3   6.3   355   16    8   5.8   3.2  -10.4  13.2     1.0      M    M
  8250  -13.9   7.0   360   16    8   6.0   3.3  -10.7  12.7     0.7      M    M
  8000  -13.4   7.9   005   16    8   7.4   4.1  -11.0  12.3     0.4      M    M
  7750  -12.8   9.0   005   14    7   8.5   4.7  -11.1  12.1     0.3      M    M
  7500  -12.2  10.0   010   12    6   7.7   4.2  -11.2  11.8     0.2      M    M
  7250  -11.6  11.1   010    9    5   9.8   5.4  -11.3  11.6     0.1      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 * * * * * *

           12/07/2016 at 0800 MST          |       12/07/2016 at 1100 MST
                                           |
K index... -7.4  LI... +2.5                | K index... -27.2  LI... +5.9
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.2
                                           |
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 -59.3 -74.7  270  63 33   3.4   1.8 | -58.7 -73.7  265  72 37   2.7   1.5
 45000 -54.2 -65.6  270  74 38   3.4   1.9 | -54.7 -66.5  275  80 41   2.7   1.5
 40000 -50.6 -59.1  275  83 43   2.3   1.2 | -51.3 -60.3  275  85 44   2.0   1.1
 38000 -49.3 -56.7  275  86 44   1.2   0.7 | -50.2 -58.4  275  87 45   0.6   0.4
 36000 -48.8 -55.8  275  92 48   0.7   0.4 | -49.7 -57.5  275  90 46   0.8   0.4
 34000 -48.4 -55.1  275 100 51   0.7   0.4 | -49.3 -56.7  275  93 48   0.8   0.4
 32000 -47.2 -53.0  275 104 54   2.4   1.3 | -47.8 -54.0  275  95 49   3.3   1.8
 30000 -45.8 -50.4  275 108 56   2.4   1.3 | -45.8 -50.4  275  97 50   3.3   1.8
 29000 -44.7 -48.5  275 110 56   5.5   3.0 | -44.6 -48.3  275  98 50   5.4   3.0
 28000 -43.0 -45.4  275 110 57   5.5   3.0 | -43.0 -45.4  275  98 50   5.3   2.9
 27000 -41.4 -42.5  275 110 57   5.5   3.0 | -41.0 -41.8  275  98 50   5.3   2.9
 26000 -39.8 -39.6  275 111 57   5.1   2.8 | -39.4 -38.9  275  97 50   5.0   2.7
 25000 -38.3 -36.9  275 107 55   4.7   2.6 | -38.0 -36.4  275  95 49   4.9   2.7
 24000 -36.9 -34.4  275 102 53   4.7   2.6 | -36.5 -33.7  280  93 48   4.9   2.7
 23000 -35.5 -31.9  275  98 50   4.2   2.3 | -35.0 -31.0  280  90 46   4.2   2.3
 22000 -34.6 -30.3  275  89 46   2.8   1.5 | -33.9 -29.0  280  84 43   3.8   2.1
 21000 -33.8 -28.8  275  79 41   2.8   1.5 | -32.8 -27.0  280  79 40   3.8   2.1
 20000 -33.0 -27.4  275  70 36   1.5   0.8 | -31.8 -25.2  280  72 37   2.0   1.1
 19500 -32.8 -27.0  275  67 34   1.4   0.8 | -31.4 -24.5  280  68 35   2.1   1.2
 19000 -32.6 -26.7  275  64 33   1.4   0.8 | -31.1 -24.0  280  64 33   2.1   1.2
 18500 -32.4 -26.3  275  60 31   1.4   0.8 | -30.8 -23.4  275  60 31   2.1   1.2
 18000 -32.2 -26.0  270  57 29   1.2   0.7 | -30.5 -22.9  275  57 29   2.2   1.2
 17500 -31.9 -25.4  270  54 28   3.2   1.8 | -30.2 -22.4  275  53 27   1.9   1.0
 17000 -31.4 -24.5  270  50 26   3.2   1.8 | -29.9 -21.8  275  49 25   1.9   1.0
 16500 -30.9 -23.6  270  46 24   7.1   3.9 | -29.6 -21.3  275  45 23   3.1   1.7
 16000 -28.8 -19.8  265  41 21   9.4   5.1 | -29.1 -20.4  280  42 22   3.5   1.9
 15500 -27.4 -17.3  265  37 19   9.3   5.1 | -28.5 -19.3  280  39 20   5.2   2.9
 15000 -26.0 -14.8  270  34 17   9.3   5.1 | -27.5 -17.5  280  36 18   6.7   3.7
 14500 -24.7 -12.5  270  31 16   7.8   4.3 | -26.5 -15.7  275  33 17   7.7   4.2
 14000 -23.6 -10.5  275  29 15   7.6   4.2 | -25.2 -13.4  275  32 16   9.2   5.1
 13500 -22.4  -8.3  280  28 14   8.3   4.6 | -23.2  -9.8  275  30 15   8.5   4.6
 13000 -21.1  -6.0  285  26 13   8.5   4.7 | -21.9  -7.4  280  29 15   8.4   4.6
 12500 -19.8  -3.6  290  24 13   9.6   5.3 | -20.7  -5.3  285  28 14   7.7   4.2
 12000 -18.3  -0.9  290  23 12   9.5   5.2 | -19.6  -3.3  290  26 14   8.5   4.7
 11750 -17.7   0.1  295  23 12   7.9   4.3 | -18.9  -2.0  290  25 13   7.3   4.0
 11500 -17.1   1.2  295  22 12   6.7   3.7 | -18.6  -1.5  295  24 12   4.3   2.4
 11250 -16.6   2.1  300  22 11   6.0   3.3 | -18.3  -0.9  295  23 12   3.8   2.1
 11000 -16.2   2.8  300  22 11   7.1   3.9 | -18.0  -0.4  300  22 11   5.6   3.1
 10750 -15.7   3.7  305  22 11   4.4   2.4 | -17.6   0.3  300  21 11   1.1   0.6
 10500 -15.6   3.9  310  22 11  -0.1  -0.1 | -17.8  -0.0  310  19 10  -3.7  -2.0
 10250 -15.6   3.9  315  21 11  -0.6  -0.3 | -18.1  -0.6  320  17  9  -3.1  -1.7
 10000 -15.7   3.7  315  21 11  -0.3  -0.2 | -18.3  -0.9  330  16  8  -0.6  -0.3
  9750 -15.7   3.7  320  21 11  -0.9  -0.5 | -18.1  -0.6  340  15  8   6.4   3.5
  9500 -15.8   3.6  330  21 11  -1.3  -0.7 | -17.5   0.5  350  15  8   8.5   4.6
  9250 -15.9   3.4  335  20 10  -1.7  -0.9 | -16.9   1.6  355  16  8   7.4   4.0
  9000 -16.0   3.2  340  20 10   0.0   0.0 | -16.3   2.7  360  16  8   8.8   4.9
  8750 -15.9   3.4  350  19 10   5.1   2.8 | -15.6   3.9  005  16  8  10.6   5.8
  8500 -15.3   4.5  355  18  9   7.7   4.2 | -14.8   5.4  005  15  8  10.8   5.9
  8250 -14.8   5.4  355  18  9   7.5   4.1 | -14.0   6.8  005  15  8  10.9   6.0
  8000 -14.2   6.4  360  17  9   8.7   4.8 | -13.2   8.2  010  15  8  11.6   6.3
  7750 -13.5   7.7  360  16  8   8.9   4.9 | -12.3   9.9  010  14  7  10.6   5.8
  7500 -12.9   8.8  360  15  8   8.4   4.6 | -11.6  11.1  010  14  7   8.1   4.5
  7250 -12.3   9.9  005  13  7   6.9   3.8 | -11.0  12.2  010  13  7   9.5   5.2
  7000 -11.9  10.6  005  12  6   3.4   1.9 | -10.2  13.6  010  13  6  13.1   7.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/07/2016 at 1400 MST          |       12/07/2016 at 1700 MST
                                           |
K index... -7.7  LI... +4.6                | K index... -23.1  LI... +6.3
CAPE... +5.5  CIN... -1.7                  | CAPE... 0.0  CIN... -6.1
                                           |
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 -58.8 -73.8  270  73 37   2.3   1.3 | -58.7 -73.7  280  66 34   2.4   1.3
 45000 -55.3 -67.5  275  82 42   2.3   1.3 | -55.0 -67.0  280  81 41   2.5   1.3
 40000 -52.3 -62.1  280  88 45   2.0   1.1 | -52.9 -63.2  280  92 47   1.2   0.7
 38000 -51.1 -60.0  280  90 46   1.3   0.7 | -52.2 -62.0  280  96 49   0.9   0.5
 36000 -50.5 -58.9  280  91 47   1.1   0.6 | -51.6 -60.9  280  97 50   0.9   0.5
 34000 -49.7 -57.5  275  91 47   1.2   0.6 | -51.1 -60.0  280  99 51   1.0   0.5
 32000 -47.8 -54.0  280  92 48   3.8   2.1 | -49.2 -56.6  285 100 51   4.1   2.3
 30000 -45.6 -50.1  280  93 48   3.8   2.1 | -46.7 -52.1  285 100 52   4.2   2.3
 29000 -44.2 -47.6  280  94 48   5.1   2.8 | -45.2 -49.4  285 101 52   6.3   3.4
 28000 -42.6 -44.7  280  94 48   5.2   2.8 | -43.3 -45.9  285 102 53   6.3   3.5
 27000 -41.1 -42.0  280  94 48   5.2   2.8 | -40.9 -41.6  285 103 53   6.3   3.5
 26000 -39.5 -39.1  280  94 48   4.8   2.7 | -39.1 -38.4  285 104 53   5.2   2.9
 25000 -38.1 -36.6  280  92 47   4.6   2.5 | -37.5 -35.5  285 102 52   5.3   2.9
 24000 -36.8 -34.2  280  90 46   4.6   2.5 | -35.9 -32.6  285 100 51   5.3   2.9
 23000 -35.4 -31.7  280  88 45   4.7   2.6 | -34.3 -29.7  285  97 50   4.9   2.7
 22000 -33.9 -29.0  280  85 44   4.8   2.7 | -32.9 -27.2  285  93 48   4.8   2.6
 21000 -32.4 -26.3  280  82 42   4.9   2.7 | -31.5 -24.7  285  89 46   4.8   2.6
 20000 -31.3 -24.3  280  77 40   0.7   0.4 | -30.4 -22.7  285  83 43   1.2   0.6
 19500 -31.1 -24.0  280  73 38   1.1   0.6 | -30.2 -22.4  285  78 40   1.3   0.7
 19000 -30.9 -23.6  280  69 36   1.1   0.6 | -30.0 -22.0  285  73 38   1.3   0.7
 18500 -30.8 -23.4  280  65 34   1.2   0.6 | -29.8 -21.6  285  68 35   1.3   0.7
 18000 -30.6 -23.1  285  61 31   1.5   0.8 | -29.6 -21.3  285  63 32   1.0   0.5
 17500 -30.7 -23.3  280  57 29  -2.3  -1.3 | -29.7 -21.5  285  57 29  -1.0  -0.5
 17000 -31.0 -23.8  280  53 27  -2.1  -1.2 | -29.8 -21.6  285  51 26  -1.0  -0.5
 16500 -30.7 -23.3  280  47 24   5.2   2.9 | -29.8 -21.6  285  46 23   0.4   0.2
 16000 -30.0 -22.0  280  43 22   4.4   2.4 | -29.8 -21.6  280  41 21   0.2   0.1
 15500 -28.9 -20.0  280  40 20  10.0   5.5 | -29.5 -21.1  280  37 19   6.6   3.6
 15000 -27.5 -17.5  280  38 19   9.5   5.2 | -28.2 -18.8  280  34 18   8.4   4.6
 14500 -26.1 -15.0  280  36 18   9.1   5.0 | -27.0 -16.6  280  32 16   8.9   4.9
 14000 -24.7 -12.5  280  33 17   9.2   5.1 | -25.6 -14.1  285  31 16   9.2   5.0
 13500 -23.4 -10.1  280  31 16   8.1   4.5 | -23.6 -10.5  285  28 15   8.6   4.7
 13000 -22.2  -8.0  280  29 15   8.1   4.4 | -22.3  -8.1  285  27 14   8.8   4.8
 12500 -21.0  -5.8  280  26 14   7.6   4.2 | -21.1  -6.0  290  25 13   7.0   3.8
 12000 -19.9  -3.8  280  24 13   6.9   3.8 | -20.1  -4.2  290  23 12   6.7   3.7
 11750 -19.5  -3.1  280  23 12   3.8   2.1 | -19.6  -3.3  290  22 11   4.8   2.6
 11500 -19.3  -2.7  285  20 10   2.4   1.3 | -19.4  -2.9  290  20 10   3.5   1.9
 11250 -19.1  -2.4  285  18  9   2.1   1.2 | -19.1  -2.4  290  18  9   5.1   2.8
 11000 -18.9  -2.0  290  15  8   3.9   2.1 | -18.8  -1.8  285  16  8  -0.1  -0.0
 10750 -18.6  -1.5  290  13  7   3.9   2.2 | -19.0  -2.2  290  14  7  -0.6  -0.4
 10500 -18.4  -1.1  300  11  5   2.3   1.3 | -18.8  -1.8  290  12  6   4.4   2.4
 10250 -18.2  -0.8  315   8  4   2.4   1.3 | -18.5  -1.3  290   9  5   2.1   1.1
 10000 -18.0  -0.4  340   7  3   3.5   1.9 | -18.3  -0.9  290   7  3   6.2   3.4
  9750 -17.6   0.3  360   6  3   7.4   4.0 | -17.7   0.1  300   5  3   7.6   4.2
  9500 -17.0   1.4  010   7  4   9.1   5.0 | -17.3   0.9  325   4  2   4.4   2.4
  9250 -16.3   2.7  020   8  4   8.6   4.7 | -16.9   1.6  360   4  2   5.0   2.7
  9000 -15.7   3.7  025   9  5   9.3   5.1 | -16.5   2.3  025   5  3   6.9   3.8
  8750 -14.9   5.2  030   9  5  10.0   5.5 | -15.9   3.4  030   6  3   8.7   4.7
  8500 -14.2   6.4  030  10  5  10.2   5.6 | -15.3   4.5  035   7  4   8.8   4.8
  8250 -13.4   7.9  035  10  5  10.3   5.6 | -14.6   5.7  035   8  4   9.2   5.1
  8000 -12.7   9.1  035  11  5  10.5   5.7 | -13.9   7.0  040   9  4   9.5   5.2
  7750 -11.9  10.6  035  10  5  10.0   5.5 | -13.2   8.2  040   9  4   9.3   5.1
  7500 -11.2  11.8  035  10  5   9.1   5.0 | -12.6   9.3  040   8  4   8.0   4.4
  7250 -10.5  13.1  035  10  5   9.0   5.0 | -12.0  10.4  040   8  4   6.7   3.6
  7000  -9.8  14.4  035  10  5   9.3   5.1 | -11.5  11.3  040   8  4   6.2   3.4
  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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