Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 061121
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0421 MST Tuesday, December 6, 2016

This forecast is for Tuesday, December 6, 2016:

If the trigger temperature of 30.0 F/-1.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 90 ft/min (0.5 m/s)
   Maximum height of thermals.................. 9809 ft MSL (3051 ft AGL)

Forecast maximum temperature................... 25.0 F/-4.3 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1100 MST
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8783 ft MSL (2026 ft AGL)
Thermal soaring outlook for Wednesday 12/07.... Poor

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

Remarks...

Sunrise/Sunset.................... 07:03:53 / 16:36:48 MST
Total possible sunshine........... 9 hr 32 min 55 sec (572 min 55 sec)
Altitude of sun at 11:50:26 MST... 28.51 degrees

Upper air data from numerical model forecast valid on 12/06/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 17089 ft MSL (10331 ft AGL)
Lifted condensation level....... 12259 ft MSL (5502 ft AGL)
Lifted index.................... +12.5
K index......................... -9.8

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  -60.1 -76.2   260   62   32   2.0   1.1      M     M       M      M    M
 45000  -57.1 -70.8   265   80   41   2.0   1.1      M     M       M      M    M
 40000  -54.9 -66.8   270   82   42   1.3   0.7      M     M       M      M    M
 38000  -54.2 -65.6   270   82   42  -0.1  -0.0      M     M       M      M    M
 36000  -54.4 -65.9   270   82   42  -0.3  -0.2      M     M       M      M    M
 34000  -54.6 -66.3   265   83   43  -0.3  -0.2      M     M       M      M    M
 32000  -53.3 -63.9   270   81   42   3.2   1.8      M     M       M      M    M
 30000  -51.4 -60.5   275   79   41   3.3   1.8      M     M       M      M    M
 29000  -49.2 -56.6   275   79   41   7.7   4.2   17.6  63.8    16.6      M    M
 28000  -47.0 -52.6   275   80   41   7.6   4.2   16.8  62.2    16.1      M    M
 27000  -44.7 -48.5   275   81   42   7.6   4.2   16.0  60.8    15.7      M    M
 26000  -42.3 -44.1   280   82   42   8.4   4.6   15.4  59.7    15.4      M    M
 25000  -39.8 -39.6   280   82   42   8.4   4.6   14.8  58.6    15.1      M    M
 24000  -37.3 -35.1   280   82   42   8.4   4.6   14.3  57.7    14.9      M    M
 23000  -34.9 -30.8   280   82   42   7.5   4.1   13.8  56.8    14.7      M    M
 22000  -32.6 -26.7   280   81   42   7.6   4.2   12.9  55.3    14.1      M    M
 21000  -30.3 -22.5   280   81   41   7.6   4.2   12.2  54.0    13.7      M    M
 20000  -28.2 -18.8   280   79   41   6.5   3.6   11.3  52.4    13.1      M    M
 19500  -27.2 -17.0   280   78   40   6.5   3.5   10.7  51.3    12.6      M    M
 19000  -26.2 -15.2   280   77   39   6.5   3.5   10.1  50.3    12.2      M    M
 18500  -25.3 -13.5   280   75   39   6.5   3.6    9.6  49.3    11.8      M    M
 18000  -24.3 -11.7   280   74   38   6.6   3.6    9.1  48.4    11.4      M    M
 17500  -23.3  -9.9   280   72   37   6.8   3.7    8.6  47.4    11.0      M    M
 17000  -22.3  -8.1   280   71   36   6.8   3.7    8.1  46.5    10.6      M    M
 16500  -21.3  -6.3   280   69   35   6.6   3.6    7.6  45.6    10.3      M    M
 16000  -20.3  -4.5   280   67   34   6.8   3.7    7.0  44.7     9.8      M    M
 15500  -19.4  -2.9   280   65   34   3.9   2.2    6.4  43.5     9.3      M    M
 15000  -18.9  -2.0   280   63   33   3.3   1.8    5.3  41.6     8.4      M    M
 14500  -18.5  -1.3   280   61   32   3.3   1.8    4.3  39.7     7.5      M    M
 14000  -17.7   0.1   275   56   29   3.0   1.7    2.7  36.8     6.0      M    M
 13500  -17.0   1.4   270   52   27   7.9   4.3    2.0  35.5     5.3      M    M
 13000  -15.9   3.4   270   49   25   8.0   4.4    1.7  35.0     5.0      M    M
 12500  -14.7   5.5   270   45   23   7.9   4.4    1.4  34.5     4.8      M    M
 12000  -13.5   7.7   270   42   22   7.5   4.1    1.1  34.0     4.5      M    M
 11750  -13.0   8.6   270   41   21   5.6   3.1    0.9  33.6     4.3      M    M
 11500  -12.7   9.1   265   38   20   3.7   2.0    0.4  32.8     3.9      M    M
 11250  -12.5   9.5   265   35   18   3.1   1.7   -0.1  31.9     3.4      M    M
 11000  -12.2  10.0   265   32   17   4.4   2.4   -0.6  31.0     2.9      M    M
 10750  -11.9  10.6   265   30   15   3.1   1.7   -1.0  30.3     2.6      M    M
 10500  -11.8  10.8   260   27   14   0.1   0.0   -1.6  29.0     1.9      M    M
 10250  -11.8  10.8   255   23   12   0.9   0.5   -2.4  27.7     1.2      M    M
 10000  -11.7  10.9   250   20   10  -1.4  -0.8   -3.1  26.4     0.5      M    M
  9750  -11.9  10.6   245   16    8  -1.6  -0.9   -4.0  24.7    -0.4    289  1.5
  9500  -11.9  10.6   240   13    7   0.5   0.3   -4.8  23.4    -1.1    282  1.4
  9250  -11.9  10.6   230   11    6  -0.3  -0.2   -5.5  22.0    -1.8    274  1.4
  9000  -11.9  10.6   220    9    5   1.0   0.6   -6.3  20.7    -2.5    266  1.4
  8750  -11.7  10.9   205    8    4   1.3   0.7   -6.9  19.6    -3.1    255  1.3
  8500  -11.7  10.9   195    7    4  -0.1  -0.1   -7.6  18.3    -3.9    247  1.3
  8250  -11.7  10.9   180    8    4  -0.4  -0.2   -8.4  17.1    -4.6    240  1.2
  8000  -11.7  10.9   165    8    4   1.0   0.6   -9.1  15.6    -5.3    232  1.2
  7750  -11.6  11.1   165    8    4   2.6   1.4   -9.7  14.6    -5.9    220  1.1
  7500  -11.3  11.7   160    7    4   4.1   2.3  -10.2  13.7    -6.4    206  1.0
  7250  -11.1  12.0   145    6    3   0.8   0.5  -10.6  12.9    -6.9    190  1.0
  7000  -11.4  11.5   140    5    3  -8.9  -4.9  -11.1  11.9    -7.4    192  1.0
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           12/06/2016 at 0800 MST          |       12/06/2016 at 1100 MST
                                           |
K index... -12.3  LI... +4.9               | K index... -5.4  LI... +3.5
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 -59.0 -74.2  265  56 29   1.6   0.9 | -58.2 -72.8  270  62 32   1.0   0.6
 45000 -56.6 -69.9  270  82 42   1.6   0.9 | -56.7 -70.1  270  83 43   1.0   0.6
 40000 -55.1 -67.2  270  83 43   0.7   0.4 | -54.4 -65.9  270  86 45   1.5   0.8
 38000 -54.7 -66.5  265  81 42  -0.1  -0.0 | -53.5 -64.3  270  86 44  -0.2  -0.1
 36000 -54.9 -66.8  265  81 42  -0.4  -0.2 | -54.0 -65.2  270  83 43  -0.7  -0.4
 34000 -55.1 -67.2  265  81 42  -0.3  -0.2 | -54.4 -65.9  265  81 42  -0.7  -0.4
 32000 -53.9 -65.0  270  79 41   3.4   1.8 | -53.3 -63.9  265  76 39   3.2   1.7
 30000 -51.8 -61.2  270  76 39   3.5   1.9 | -51.4 -60.5  265  71 37   3.3   1.8
 29000 -49.7 -57.5  270  75 39   7.8   4.3 | -49.8 -57.6  265  68 35   7.4   4.0
 28000 -47.3 -53.1  270  74 38   7.8   4.3 | -47.6 -53.7  260  65 33   7.4   4.0
 27000 -45.0 -49.0  275  73 38   7.8   4.3 | -44.9 -48.8  255  61 31   7.4   4.1
 26000 -42.6 -44.7  275  73 37   8.3   4.6 | -42.6 -44.7  255  59 30   7.8   4.3
 25000 -40.1 -40.2  275  72 37   8.3   4.6 | -40.3 -40.5  260  60 31   7.7   4.3
 24000 -37.6 -35.7  275  72 37   8.3   4.6 | -38.0 -36.4  260  61 32   7.7   4.3
 23000 -35.2 -31.4  275  71 37   7.2   3.9 | -35.6 -32.1  260  62 32   8.0   4.4
 22000 -33.0 -27.4  275  71 36   7.3   4.0 | -33.2 -27.8  260  62 32   8.0   4.4
 21000 -30.8 -23.4  275  70 36   7.3   4.0 | -30.8 -23.4  265  62 32   8.0   4.4
 20000 -28.7 -19.7  275  69 36   7.1   3.9 | -28.7 -19.7  265  61 31   6.5   3.5
 19500 -27.6 -17.7  275  69 35   7.1   3.9 | -27.7 -17.9  265  61 31   6.4   3.5
 19000 -26.5 -15.7  275  68 35   7.1   3.9 | -26.8 -16.2  265  60 31   6.4   3.5
 18500 -25.5 -13.9  275  68 35   7.1   3.9 | -25.8 -14.4  270  60 31   6.4   3.5
 18000 -24.4 -11.9  275  67 35   7.1   3.9 | -24.9 -12.8  270  60 31   6.4   3.5
 17500 -23.4 -10.1  275  66 34   7.1   3.9 | -23.9 -11.0  270  58 30   6.4   3.5
 17000 -22.3  -8.1  275  65 33   7.2   4.0 | -23.0  -9.4  270  56 29   6.4   3.5
 16500 -21.3  -6.3  275  63 33   5.7   3.1 | -21.9  -7.4  270  54 28   7.2   3.9
 16000 -20.4  -4.7  275  62 32   5.8   3.2 | -20.8  -5.4  270  51 26   7.2   3.9
 15500 -19.5  -3.1  275  60 31   6.7   3.7 | -19.7  -3.5  270  49 25   7.2   3.9
 15000 -18.5  -1.3  275  59 30   6.9   3.8 | -18.7  -1.7  270  47 24   7.2   3.9
 14500 -17.0   1.4  275  57 29   5.3   2.9 | -17.6   0.3  270  46 24   7.6   4.2
 14000 -16.2   2.8  275  55 28   5.6   3.0 | -16.4   2.5  270  47 24   7.8   4.3
 13500 -15.4   4.3  275  52 27   5.1   2.8 | -15.2   4.6  275  48 25   7.5   4.1
 13000 -14.7   5.5  275  50 26   5.1   2.8 | -14.1   6.6  270  46 24   7.2   3.9
 12500 -13.9   7.0  275  46 24   6.1   3.3 | -13.1   8.4  270  43 22   7.3   4.0
 12000 -13.0   8.6  270  43 22   6.9   3.8 | -12.0  10.4  270  40 21   7.3   4.0
 11750 -12.5   9.5  270  41 21   6.1   3.3 | -11.4  11.5  270  39 20   7.2   3.9
 11500 -12.1  10.2  270  38 20   4.5   2.5 | -11.0  12.2  270  38 19   5.2   2.8
 11250 -11.8  10.8  270  36 19   3.8   2.1 | -10.7  12.7  270  35 18   3.5   1.9
 11000 -11.5  11.3  265  34 17   5.8   3.2 | -10.5  13.1  265  33 17   2.9   1.6
 10750 -11.1  12.0  265  32 16   4.5   2.5 | -10.2  13.6  265  31 16   6.5   3.6
 10500 -11.0  12.2  265  29 15   0.0   0.0 |  -9.7  14.5  260  28 14   2.6   1.4
 10250 -11.0  12.2  260  27 14   0.9   0.5 |  -9.9  14.2  260  26 13  -4.0  -2.2
 10000 -10.9  12.4  255  24 12  -2.4  -1.3 | -10.3  13.5  250  22 11  -2.7  -1.5
  9750 -11.3  11.7  250  21 11  -3.8  -2.1 | -10.6  12.9  245  20 10  -5.0  -2.7
  9500 -11.4  11.5  240  19 10  -1.3  -0.7 | -11.1  12.0  235  18 10  -6.6  -3.6
  9250 -11.5  11.3  230  17  9  -2.1  -1.2 | -11.5  11.3  220  17  9  -6.8  -3.7
  9000 -11.7  10.9  220  16  8  -1.2  -0.7 | -12.0  10.4  210  17  9  -4.5  -2.5
  8750 -11.7  10.9  210  15  8  -1.5  -0.8 | -12.1  10.2  200  16  8   3.4   1.9
  8500 -11.9  10.6  200  15  8  -2.7  -1.5 | -11.6  11.1  190  16  8   6.7   3.7
  8250 -12.1  10.2  190  15  8  -3.7  -2.0 | -11.1  12.0  180  17  8   6.3   3.5
  8000 -12.3   9.9  185  16  8   0.2   0.1 | -10.6  12.9  175  17  9   8.6   4.7
  7750 -12.1  10.2  185  15  8   3.5   1.9 |  -9.8  14.4  175  16  8  14.8   8.1
  7500 -11.9  10.6  180  13  7   2.4   1.3 |  -8.3  17.1  175  15  8  22.7  12.5
  7250 -11.7  10.9  175  11  5   1.5   0.8 |  -6.9  19.6  170  14  7   9.3   5.1
  7000 -11.7  10.9  170   8  4  -2.1  -1.1 |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/06/2016 at 1400 MST          |       12/06/2016 at 1700 MST
                                           |
K index... +11.5  LI... +2.0               | K index... +15.0  LI... +0.5
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -8.2
                                           |
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 -58.2 -72.8  265  75 38   0.9   0.5 | -58.6 -73.5  265  62 32   1.2   0.6
 45000 -56.8 -70.2  270  85 44   0.9   0.5 | -56.8 -70.2  270  78 40   1.2   0.6
 40000 -54.4 -65.9  270  89 46   1.7   0.9 | -53.6 -64.5  275  85 44   2.2   1.2
 38000 -53.5 -64.3  270  89 46   0.5   0.3 | -52.4 -62.3  275  86 44   0.7   0.4
 36000 -53.3 -63.9  270  84 43   0.2   0.1 | -52.2 -62.0  275  86 44   0.4   0.2
 34000 -53.2 -63.8  270  79 41   0.3   0.1 | -52.0 -61.6  270  86 44   0.4   0.2
 32000 -51.7 -61.1  270  76 39   3.6   2.0 | -50.7 -59.3  270  84 43   2.9   1.6
 30000 -49.6 -57.3  270  74 38   3.6   2.0 | -49.0 -56.2  270  81 41   3.0   1.6
 29000 -48.3 -54.9  270  73 38   5.6   3.1 | -47.8 -54.0  270  79 41   5.4   2.9
 28000 -46.6 -51.9  270  71 37   5.6   3.0 | -46.2 -51.2  270  78 40   5.3   2.9
 27000 -44.9 -48.8  265  70 36   5.6   3.1 | -44.7 -48.5  270  77 40   5.3   2.9
 26000 -42.7 -44.9  265  67 35   7.0   3.8 | -42.6 -44.7  270  76 39   6.5   3.5
 25000 -40.7 -41.3  260  62 32   6.8   3.8 | -40.7 -41.3  270  73 38   6.4   3.5
 24000 -38.6 -37.5  260  56 29   6.8   3.8 | -38.7 -37.7  265  71 36   6.4   3.5
 23000 -36.5 -33.7  260  53 27   8.1   4.4 | -36.8 -34.2  265  68 35   6.6   3.6
 22000 -34.1 -29.4  260  56 29   8.0   4.4 | -34.8 -30.6  265  63 32   6.7   3.7
 21000 -31.7 -25.1  260  59 31   8.0   4.4 | -32.8 -27.0  265  58 30   6.7   3.7
 20000 -29.4 -20.9  260  62 32   7.6   4.1 | -30.6 -23.1  265  56 29   8.7   4.7
 19500 -28.3 -18.9  260  63 33   7.5   4.1 | -29.3 -20.7  265  56 29   8.7   4.7
 19000 -27.1 -16.8  265  65 33   7.6   4.1 | -28.0 -18.4  265  57 29   8.7   4.7
 18500 -26.0 -14.8  265  66 34   7.5   4.1 | -26.7 -16.1  265  57 30   8.6   4.7
 18000 -24.9 -12.8  265  67 35   7.3   4.0 | -25.4 -13.7  265  58 30   8.1   4.5
 17500 -23.9 -11.0  270  66 34   6.8   3.7 | -24.4 -11.9  260  60 31   6.9   3.8
 17000 -22.9  -9.2  270  65 33   6.8   3.7 | -23.3  -9.9  260  62 32   6.8   3.7
 16500 -21.8  -7.2  270  63 32   7.3   4.0 | -22.2  -8.0  255  62 32   8.6   4.7
 16000 -20.8  -5.4  270  61 31   7.3   4.0 | -20.9  -5.6  255  60 31   8.5   4.6
 15500 -19.7  -3.5  275  58 30   6.8   3.7 | -19.7  -3.5  255  58 30   8.1   4.4
 15000 -18.7  -1.7  275  55 29   6.7   3.7 | -18.5  -1.3  260  57 29   8.0   4.4
 14500 -17.7   0.1  275  53 27   6.7   3.7 | -17.3   0.9  260  56 29   7.7   4.2
 14000 -16.7   1.9  270  49 25   6.8   3.7 | -16.2   2.8  260  54 28   7.4   4.0
 13500 -15.7   3.7  270  46 23   7.4   4.1 | -15.1   4.8  260  53 27   7.4   4.1
 13000 -14.5   5.9  265  43 22   8.3   4.6 | -14.0   6.8  260  49 25   7.6   4.2
 12500 -13.2   8.2  260  40 21   8.3   4.6 | -12.9   8.8  255  44 23   7.8   4.3
 12000 -12.0  10.4  260  37 19   7.8   4.3 | -11.7  10.9  255  42 21   8.0   4.4
 11750 -11.4  11.5  255  36 19   6.9   3.8 | -11.2  11.8  250  40 21   7.2   3.9
 11500 -11.0  12.2  255  35 18   5.3   2.9 | -10.7  12.7  250  38 20   5.8   3.2
 11250 -10.7  12.7  250  33 17   3.1   1.7 | -10.3  13.5  245  37 19   3.3   1.8
 11000 -10.5  13.1  250  32 16   2.4   1.3 | -10.1  13.8  245  35 18   2.2   1.2
 10750 -10.3  13.5  245  30 16   4.0   2.2 |  -9.9  14.2  240  34 18   4.2   2.3
 10500 -10.0  14.0  245  30 15  -0.5  -0.3 |  -9.6  14.7  240  33 17   1.6   0.9
 10250 -10.4  13.3  240  28 14  -6.7  -3.7 |  -9.8  14.4  235  32 16  -3.9  -2.2
 10000 -11.3  11.7  225  24 12  -8.2  -4.5 | -10.4  13.3  225  28 14  -3.8  -2.1
  9750 -11.9  10.6  220  24 12  -4.3  -2.4 | -10.7  12.7  215  27 14  -4.3  -2.4
  9500 -11.9  10.6  210  22 11   1.0   0.6 | -11.0  12.2  210  26 13  -4.9  -2.7
  9250 -11.9  10.6  200  21 11  -0.9  -0.5 | -11.4  11.5  205  25 13  -5.9  -3.2
  9000 -11.9  10.6  185  21 11   1.4   0.8 | -11.7  10.9  195  24 13  -1.3  -0.7
  8750 -11.6  11.1  185  20 11   7.4   4.0 | -11.5  11.3  190  24 12   3.5   1.9
  8500 -10.9  12.4  180  20 10   9.9   5.4 | -11.3  11.7  185  23 12   2.5   1.4
  8250 -10.2  13.6  180  20 10   9.2   5.1 | -11.1  12.0  180  23 12   2.2   1.2
  8000  -9.5  14.9  175  20 10   9.5   5.2 | -10.9  12.4  175  23 12   4.5   2.5
  7750  -8.6  16.5  175  20 10  14.1   7.8 | -10.4  13.3  180  22 11   8.7   4.8
  7500  -7.3  18.9  175  18  9  21.7  11.9 |  -9.7  14.5  175  18  9   8.1   4.4
  7250  -5.9  21.4  175  17  9   8.3   4.5 |  -9.1  15.6  170  15  7  11.4   6.2
  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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