Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 271236
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0536 MST Thursday, November 27, 2014

This forecast is for Thursday, November 27, 2014:

If the trigger temperature of 62.0 F/16.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 153 ft/min (0.8 m/s)
   Maximum height of thermals.................. 10578 ft MSL (5293 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 1045 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9128 ft MSL (3842 ft AGL)
Thermal soaring outlook for Friday 11/28....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 14371 ft MSL (9086 ft AGL)
Wave soaring outlook for Friday 11/28.......... Good

Remarks...

Sunrise/Sunset.................... 06:57:26 / 16:36:51 MST
Total possible sunshine........... 9 hr 39 min 25 sec (579 min 25 sec)
Altitude of sun at 11:47:17 MST... 29.08 degrees

Upper air data from rawinsonde observation taken on 11/27/2014 at 0500 MST

Freezing level.................. 12494 ft MSL (7209 ft AGL)
Convective condensation level... 20832 ft MSL (15547 ft AGL)
Lifted condensation level....... 18515 ft MSL (13229 ft AGL)
Lifted index.................... +6.8
K index......................... -17.7

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -69.5 -93.1   310   69   35  -8.2  -4.5   83.2 181.7    36.4      M    M
 45000  -64.6 -84.3   305   64   33   5.6   3.1   66.7 152.1    29.0      M    M
 40000  -58.9 -74.0   305   66   34   5.5   3.0   51.6 124.9    21.2      M    M
 38000  -60.4 -76.7   305   71   37   9.2   5.0   40.8 105.4    14.5      M    M
 36000  -55.6 -68.1   310   78   40   7.9   4.4   39.3 102.8    13.9      M    M
 34000  -50.5 -58.9   300   71   37   9.1   5.0   38.2 100.7    13.4      M    M
 32000  -45.2 -49.4   295   66   34   9.2   5.0   37.5  99.5    13.2      M    M
 30000  -40.7 -41.3   295   63   33   7.7   4.2   35.7  96.2    12.2      M    M
 29000  -38.4 -37.1   300   63   32   7.7   4.2   34.8  94.7    11.7      M    M
 28000  -36.0 -32.8   300   63   32   8.3   4.5   34.1  93.3    11.3      M    M
 27000  -32.9 -27.2   305   63   32   8.3   4.5   33.3  92.0    10.8      M    M
 26000  -30.4 -22.7   305   63   33   8.3   4.5   32.8  91.1    10.6      M    M
 25000  -28.0 -18.4   310   64   33   8.4   4.6   32.5  90.4    10.4      M    M
 24000  -25.7 -14.3   305   64   33   3.4   1.8   31.6  88.8     9.7      M    M
 23000  -24.2 -11.6   310   61   32   5.4   3.0   29.9  85.8     8.5      M    M
 22000  -22.8  -9.0   310   59   30   3.8   2.1   28.1  82.6     7.1      M    M
 21000  -21.3  -6.3   310   56   29   6.8   3.7   26.4  79.5     5.7      M    M
 20000  -19.2  -2.6   315   54   28   8.2   4.5   25.4  77.8     5.0      M    M
 19500  -17.8  -0.0   315   55   28   9.0   4.9   25.2  77.4     4.9      M    M
 19000  -16.5   2.3   315   56   29   8.2   4.5   25.1  77.2     4.8      M    M
 18500  -15.3   4.5   315   54   28   8.1   4.5   24.8  76.6     4.5      M    M
 18000  -14.1   6.6   320   51   26   8.1   4.4   24.5  76.0     4.3      M    M
 17500  -12.9   8.8   320   48   25   8.1   4.4   24.2  75.6     4.1      M    M
 17000  -11.6  11.1   325   45   23   8.8   4.8   24.0  75.2     3.9      M    M
 16500  -10.3  13.5   325   43   22   8.7   4.8   23.8  74.9     3.8      M    M
 16000   -9.0  15.8   330   40   21   8.7   4.8   23.7  74.7     3.7      M    M
 15500   -7.7  18.1   330   41   21   8.7   4.8   23.5  74.3     3.5      M    M
 15000   -6.4  20.5   330   41   21   8.7   4.8   23.3  73.9     3.4      M    M
 14500   -5.1  22.8   325   42   22   8.7   4.8   23.1  73.6     3.3      M    M
 14000   -3.2  26.2   325   43   22   8.7   4.8   22.9  73.2     3.1      M    M
 13500   -1.9  28.6   320   43   22   8.8   4.8   22.7  72.9     2.9      M    M
 13000   -0.8  30.6   320   43   22   6.5   3.6   22.4  72.2     2.6      M    M
 12500    0.2  32.4   315   44   22   6.0   3.3   21.8  71.2     2.0      M    M
 12000    1.1  34.0   315   44   22   6.1   3.3   21.2  70.2     1.5      M    M
 11500    2.0  35.6   310   41   21   6.1   3.3   20.6  69.1     1.0      M    M
 11000    2.9  37.2   310   39   20   6.3   3.4   20.0  68.0     0.4      M    M
 10500    3.7  38.7   305   37   19   3.4   1.9   19.3  66.8    -0.2    344  1.7
 10250    3.9  39.0   305   35   18   2.9   1.6   18.8  65.8    -0.8    330  1.7
 10000    4.1  39.4   305   32   17   3.2   1.7   18.3  64.9    -1.3    316  1.6
  9750    4.3  39.7   300   30   15   3.1   1.7   17.7  63.9    -1.8    302  1.5
  9500    4.6  40.3   290   28   14   3.3   1.8   17.2  63.0    -2.3    288  1.5
  9250    4.8  40.6   285   26   13   2.5   1.3   16.7  62.1    -2.8    275  1.4
  9000    5.0  41.0   275   25   13   5.9   3.2   16.2  61.2    -3.3    261  1.3
  8750    5.6  42.1   280   24   12   9.3   5.1   16.1  61.0    -3.4    234  1.2
  8500    6.3  43.3   280   23   12   8.3   4.6   16.0  60.8    -3.5    208  1.1
  8250    6.9  44.4   280   23   12   8.6   4.7   15.9  60.7    -3.6    181  0.9
  8000    7.5  45.5   285   22   11   8.5   4.7   15.8  60.5    -3.7    155  0.8
  7750    8.2  46.8   285   20   10   8.7   4.7   15.7  60.3    -3.8    129  0.7
  7500    8.8  47.8   285   18    9   8.2   4.5   15.7  60.2    -4.0    102  0.5
  7250    9.4  48.9   290   17    9  10.0   5.5   15.6  60.0    -4.1     76  0.4
  7000   10.1  50.2   290   15    8   3.1   1.7   15.5  59.9    -4.2     50  0.3
  6750    9.9  49.8   280   12    6  -1.0  -0.6   14.6  58.3    -5.1     47  0.2
  6500   10.1  50.2   265   10    5   5.6   3.1   14.1  57.4    -5.6     34  0.2
  6250   10.6  51.1   250    9    5   6.6   3.6   13.8  56.9    -5.9     12  0.1
  6000   11.0  51.8   225    9    5   6.3   3.4   13.6  56.5    -6.2      M    M
  5750   11.5  52.7   225    6    3   6.5   3.6   13.3  56.0    -6.5      M    M
  5500   11.0  51.8   225    3    2 -29.8 -16.3   12.2  54.0    -7.7      M    M

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

           11/27/2014 at 0800 MST          |       11/27/2014 at 1100 MST
                                           |
K index... +7.2  LI... +3.9                | K index... +12.0  LI... +2.5
CAPE... 0.0  CIN... -1.0                   | 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 -64.5 -84.1  305  54 28  -0.7  -0.4 | -65.2 -85.4  295  55 28   0.1   0.0
 45000 -65.3 -85.5  305  72 37   2.5   1.4 | -64.8 -84.6  300  70 36   3.4   1.8
 40000 -62.0 -79.6  310  71 37   2.3   1.3 | -60.1 -76.2  300  66 34   3.2   1.7
 38000 -58.9 -74.0  305  67 34   6.3   3.5 | -57.5 -71.5  300  65 34   4.7   2.6
 36000 -55.1 -67.2  295  62 32   6.3   3.5 | -54.7 -66.5  300  65 34   4.7   2.6
 34000 -50.9 -59.6  290  60 31   8.1   4.5 | -50.5 -58.9  300  63 32   8.2   4.5
 32000 -45.5 -49.9  300  59 31   8.1   4.4 | -45.6 -50.1  300  59 30   8.2   4.5
 30000 -40.7 -41.3  305  60 31   7.8   4.3 | -40.7 -41.3  300  57 29   8.0   4.4
 29000 -38.4 -37.1  310  61 31   7.8   4.3 | -38.3 -36.9  300  57 29   8.0   4.4
 28000 -36.0 -32.8  310  62 32   7.8   4.3 | -35.9 -32.6  300  57 29   8.0   4.4
 27000 -33.7 -28.7  315  62 32   7.6   4.2 | -33.5 -28.3  305  56 29   7.6   4.2
 26000 -31.5 -24.7  315  62 32   7.6   4.2 | -31.3 -24.3  305  55 28   7.7   4.2
 25000 -29.2 -20.6  315  63 32   7.6   4.2 | -29.0 -20.2  305  53 27   7.7   4.2
 24000 -27.0 -16.6  315  62 32   7.2   3.9 | -26.8 -16.2  310  53 27   6.5   3.6
 23000 -24.8 -12.6  315  61 32   7.2   4.0 | -24.8 -12.6  310  54 28   6.6   3.6
 22000 -22.7  -8.9  315  60 31   7.2   4.0 | -22.8  -9.0  310  55 28   6.6   3.6
 21000 -20.5  -4.9  315  58 30   7.2   4.0 | -20.8  -5.4  305  54 28   6.8   3.7
 20000 -18.4  -1.1  315  55 29   7.2   4.0 | -18.8  -1.8  305  51 26   6.8   3.7
 19500 -17.3   0.9  315  54 28   7.2   4.0 | -17.8  -0.0  305  49 25   6.8   3.7
 19000 -16.2   2.8  315  53 27   7.3   4.0 | -16.8   1.8  305  48 25   6.8   3.7
 18500 -15.1   4.8  315  51 26   7.5   4.1 | -15.8   3.6  305  45 23   7.0   3.8
 18000 -14.0   6.8  315  49 25   7.5   4.1 | -14.7   5.5  305  43 22   7.0   3.8
 17500 -12.9   8.8  315  47 24   7.5   4.1 | -13.7   7.3  305  40 21   7.6   4.2
 17000 -11.8  10.8  315  45 23   7.5   4.1 | -12.5   9.5  305  38 20   7.7   4.2
 16500 -10.6  12.9  320  43 22   7.5   4.1 | -10.8  12.6  305  35 18   7.3   4.0
 16000  -9.0  15.8  320  39 20   7.4   4.1 |  -9.7  14.5  305  33 17   7.3   4.0
 15500  -7.9  17.8  320  37 19   7.6   4.2 |  -8.6  16.5  305  31 16   8.4   4.6
 15000  -6.7  19.9  320  34 17   7.8   4.3 |  -7.3  18.9  305  30 15   9.0   4.9
 14500  -5.5  22.1  320  31 16   7.9   4.3 |  -5.9  21.4  305  29 15   9.0   4.9
 14000  -4.3  24.3  320  28 14   8.1   4.4 |  -4.6  23.7  305  29 15   8.8   4.8
 13500  -3.1  26.4  320  25 13   8.2   4.5 |  -3.3  26.1  305  29 15   8.8   4.8
 13000  -1.9  28.6  320  22 11   8.6   4.7 |  -2.0  28.4  305  31 16   8.7   4.8
 12500  -0.6  30.9  325  20 10   8.6   4.7 |  -0.7  30.7  305  32 16   8.5   4.7
 12000   0.7  33.3  325  19 10   8.7   4.8 |   0.4  32.7  305  30 15   6.3   3.5
 11500   2.0  35.6  325  19 10   8.7   4.8 |   1.4  34.5  305  27 14   6.7   3.6
 11000   3.3  37.9  320  22 11   8.3   4.5 |   2.6  36.7  305  26 13   9.5   5.2
 10500   4.6  40.3  320  25 13   7.7   4.2 |   4.0  39.2  305  26 13   8.2   4.5
 10250   5.0  41.0  320  27 14   3.9   2.1 |   4.5  40.1  305  26 13   4.2   2.3
 10000   5.3  41.5  320  27 14   6.5   3.6 |   4.8  40.6  305  25 13   7.1   3.9
  9750   6.0  42.8  315  28 15  10.8   5.9 |   5.6  42.1  305  24 12  11.0   6.0
  9500   6.7  44.1  315  30 15   8.5   4.6 |   6.3  43.3  305  22 11   9.0   4.9
  9250   7.2  45.0  310  31 16   5.1   2.8 |   6.9  44.4  305  22 11   6.7   3.7
  9000   7.6  45.7  310  32 16   4.1   2.3 |   7.4  45.3  305  23 12   7.2   3.9
  8750   7.9  46.2  305  32 17   5.3   2.9 |   8.0  46.4  305  24 12   9.3   5.1
  8500   8.3  46.9  305  32 17   4.3   2.4 |   8.7  47.7  300  24 13   7.8   4.3
  8250   8.5  47.3  300  32 17   3.2   1.7 |   9.2  48.6  300  25 13   6.2   3.4
  8000   8.8  47.8  295  32 17   3.1   1.7 |   9.7  49.5  300  25 13   6.3   3.4
  7750   9.0  48.2  295  32 16   2.8   1.5 |  10.2  50.4  295  25 13   5.7   3.1
  7500   9.1  48.4  290  30 16   0.8   0.4 |  10.5  50.9  295  25 13   3.5   1.9
  7250   9.1  48.4  290  28 14  -0.5  -0.3 |  10.7  51.3  290  24 12   2.1   1.1
  7000   9.0  48.2  285  25 13  -0.2  -0.1 |  10.8  51.4  290  22 11   3.0   1.6
  6750   9.0  48.2  280  22 12  -0.1  -0.1 |  11.0  51.8  285  21 11  -0.6  -0.3
  6500   8.9  48.0  275  20 10  -1.2  -0.6 |  10.7  51.3  280  18  9  -4.2  -2.3
  6250   8.9  48.0  270  17  9   1.9   1.0 |  10.3  50.5  275  15  8  -5.1  -2.8
  6000   8.8  47.8  260  15  8  -9.6  -5.2 |  10.0  50.0  265  12  6  -0.7  -0.4
  5750   7.1  44.8  245  12  6 -32.0 -17.6 |  10.2  50.4  255   9  4   5.7   3.1
  5500   4.4  39.9  225   9  4 -34.7 -19.0 |  10.5  50.9  240   6  3   2.8   1.6

           11/27/2014 at 1400 MST          |       11/27/2014 at 1700 MST
                                           |
K index... +8.3  LI... +3.5                | K index... +8.7  LI... +5.2
CAPE... 0.0  CIN... M                      | 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 -65.5 -85.9  295  57 29  -0.3  -0.1 | -65.1 -85.2  300  57 30  -0.9  -0.5
 45000 -65.5 -85.9  300  71 37   3.9   2.2 | -66.0 -86.8  305  71 36   3.9   2.2
 40000 -60.0 -76.0  300  67 35   3.7   2.0 | -60.5 -76.9  310  69 36   3.7   2.0
 38000 -57.7 -71.9  305  69 35   4.1   2.2 | -58.1 -72.6  310  70 36   4.0   2.2
 36000 -55.2 -67.4  305  72 37   4.1   2.2 | -55.7 -68.3  310  71 36   4.0   2.2
 34000 -51.7 -61.1  305  71 37   8.8   4.8 | -52.1 -61.8  305  70 36   9.2   5.0
 32000 -45.8 -50.4  295  66 34   8.8   4.8 | -46.6 -51.9  305  66 34   9.1   5.0
 30000 -40.5 -40.9  295  62 32   9.0   4.9 | -40.4 -40.7  300  61 32   9.3   5.1
 29000 -37.8 -36.0  295  60 31   9.0   4.9 | -37.6 -35.7  300  59 31   9.3   5.1
 28000 -35.1 -31.2  295  58 30   9.0   4.9 | -34.8 -30.6  300  58 30   9.3   5.1
 27000 -32.6 -26.7  295  54 28   7.7   4.2 | -32.2 -26.0  300  54 28   8.2   4.5
 26000 -30.3 -22.5  295  49 25   7.7   4.2 | -29.7 -21.5  300  50 26   8.2   4.5
 25000 -28.0 -18.4  300  44 23   7.7   4.2 | -27.3 -17.1  300  46 24   8.2   4.5
 24000 -25.8 -14.4  300  41 21   6.7   3.6 | -24.9 -12.8  300  43 22   7.3   4.0
 23000 -23.8 -10.8  305  42 21   6.7   3.7 | -22.7  -8.9  300  41 21   7.4   4.0
 22000 -21.7  -7.1  305  42 22   6.8   3.7 | -20.6  -5.1  305  39 20   7.4   4.0
 21000 -19.7  -3.5  305  43 22   7.0   3.8 | -18.4  -1.1  305  40 21   7.1   3.9
 20000 -17.6   0.3  305  43 22   7.0   3.8 | -16.3   2.7  305  46 24   7.1   3.9
 19500 -16.5   2.3  305  43 22   7.0   3.8 | -15.2   4.6  305  48 25   7.1   3.9
 19000 -15.5   4.1  300  44 22   7.0   3.8 | -14.1   6.6  305  51 26   7.1   3.9
 18500 -14.5   5.9  300  44 22   5.9   3.2 | -13.2   8.2  305  53 27   5.9   3.2
 18000 -13.6   7.5  300  44 22   6.0   3.3 | -12.3   9.9  305  54 28   6.0   3.3
 17500 -12.7   9.1  300  44 23   6.5   3.6 | -11.4  11.5  305  55 29   6.1   3.4
 17000 -11.7  10.9  300  45 23   6.7   3.7 | -10.5  13.1  305  56 29   6.2   3.4
 16500 -10.7  12.7  300  45 23   6.6   3.6 |  -9.6  14.7  305  56 29   6.1   3.4
 16000  -9.8  14.4  300  45 23   6.3   3.5 |  -8.7  16.3  300  56 29   5.7   3.2
 15500  -8.4  16.9  300  45 23   6.8   3.7 |  -7.4  18.7  300  55 28   5.9   3.2
 15000  -7.3  18.9  300  44 23   7.1   3.9 |  -6.6  20.1  300  53 27   6.1   3.3
 14500  -6.3  20.7  300  43 22   7.4   4.0 |  -5.7  21.7  300  51 26   6.1   3.3
 14000  -5.1  22.8  300  42 22   7.9   4.4 |  -4.8  23.4  300  49 25   6.2   3.4
 13500  -4.0  24.8  300  41 21   8.0   4.4 |  -3.9  25.0  300  47 24   6.2   3.4
 13000  -2.8  27.0  300  40 20   8.2   4.5 |  -2.8  27.0  300  45 23   7.4   4.1
 12500  -1.6  29.1  300  38 20   8.2   4.5 |  -1.8  28.8  300  42 22   7.3   4.0
 12000  -0.3  31.5  300  37 19   8.7   4.8 |  -0.7  30.7  300  40 20   7.5   4.1
 11500   1.0  33.8  295  36 18   8.7   4.8 |   0.4  32.7  300  37 19   7.4   4.1
 11000   2.2  36.0  295  34 17   8.0   4.4 |   1.6  34.9  300  34 17   7.7   4.2
 10500   3.4  38.1  295  32 16   7.5   4.1 |   2.7  36.9  295  31 16   7.6   4.1
 10250   3.9  39.0  295  31 16   3.9   2.1 |   3.2  37.8  295  30 16   3.4   1.9
 10000   4.2  39.6  295  31 16   6.5   3.5 |   3.4  38.1  295  29 15   5.6   3.1
  9750   4.9  40.8  290  30 15  10.4   5.7 |   4.1  39.4  295  27 14  10.3   5.7
  9500   5.6  42.1  290  28 15   8.6   4.7 |   4.7  40.5  290  25 13   8.8   4.8
  9250   6.1  43.0  290  27 14   5.5   3.0 |   5.3  41.5  290  23 12   6.1   3.4
  9000   6.5  43.7  285  26 14   5.8   3.2 |   5.7  42.3  285  21 11   6.5   3.6
  8750   7.0  44.6  285  25 13   8.2   4.5 |   6.3  43.3  280  19 10   9.0   4.9
  8500   7.6  45.7  285  23 12   7.4   4.0 |   7.0  44.6  275  16  8   8.4   4.6
  8250   8.1  46.6  280  21 11   6.7   3.7 |   7.6  45.7  265  14  7   8.2   4.5
  8000   8.6  47.5  275  20 10   7.0   3.8 |   8.2  46.8  260  13  7   8.7   4.8
  7750   9.2  48.6  265  18  9   7.8   4.3 |   8.9  48.0  250  12  6   9.9   5.5
  7500   9.8  49.6  260  17  9   8.7   4.8 |   9.7  49.5  240  12  6  10.1   5.5
  7250  10.4  50.7  255  16  8   8.9   4.9 |  10.4  50.7  235  11  6   9.8   5.4
  7000  11.1  52.0  245  15  8   9.5   5.2 |  11.1  52.0  235  11  6   9.9   5.4
  6750  11.8  53.2  240  14  7   8.0   4.4 |  11.8  53.2  230  11  6   8.7   4.8
  6500  12.2  54.0  235  13  7   4.5   2.5 |  12.4  54.3  230  11  6   8.0   4.4
  6250  12.5  54.5  230  11  6   2.5   1.4 |  13.0  55.4  225  11  6   5.8   3.2
  6000  12.7  54.9  225  10  5   6.3   3.5 |  13.5  56.3  220  11  6  13.6   7.5
  5750  13.3  55.9  220   9  4   9.3   5.1 |  14.5  58.1  225  11  6   3.0   1.6
  5500  13.8  56.8  215   7  3   4.2   2.3 |  13.1  55.6  210   8  4 -37.2 -20.4
________________________________________________________________________________

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 old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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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