Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 250136
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1836 MST Wednesday, December 24, 2014

This forecast is for Thursday, December 25, 2014:

If the trigger temperature of 54.6 F/12.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6233 ft MSL (946 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 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................. 5666 ft MSL (378 ft AGL)
Thermal soaring outlook for Friday 12/26....... Poor

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)................ Neither
Potential height of wave....................... 34034 ft MSL (28747 ft AGL)
Wave soaring outlook for Friday 12/26.......... Poor

Remarks... Winter storm moving over colorado on christmas day with upslope snow
           developing by afternoon and continuing into Friday.

Sunrise/Sunset.................... 07:18:46 / 16:40:39 MST
Total possible sunshine........... 9 hr 21 min 53 sec (561 min 53 sec)
Altitude of sun at 11:59:41 MST... 26.92 degrees

Upper air data from numerical model forecast valid on 12/25/2014 at 0500 MST

Freezing level.................. 5312 ft MSL (25 ft AGL)
Additional freezing level....... 9606 ft MSL (4319 ft AGL)
Convective condensation level... 15013 ft MSL (9726 ft AGL)
Lifted condensation level....... 10660 ft MSL (5373 ft AGL)
Lifted index.................... +8.6
K index......................... +18.1

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  -55.2 -67.4   245   35   18   2.9   1.6      M     M       M      M    M
 45000  -50.8 -59.4   250   42   22   2.9   1.6      M     M       M      M    M
 40000  -54.9 -66.8   245   59   30  -3.4  -1.9      M     M       M      M    M
 38000  -56.3 -69.3   245   66   34   2.6   1.4      M     M       M      M    M
 36000  -54.9 -66.8   245   71   36   2.3   1.3      M     M       M      M    M
 34000  -53.5 -64.3   245   76   39   2.2   1.2      M     M       M      M    M
 32000  -50.8 -59.4   240   69   36   5.0   2.8      M     M       M      M    M
 30000  -47.7 -53.9   240   60   31   4.8   2.6      M     M       M      M    M
 29000  -45.7 -50.3   235   57   29   8.0   4.4   27.3  81.1    16.4      M    M
 28000  -42.7 -44.9   235   54   28   8.0   4.4   26.3  79.4    16.0      M    M
 27000  -40.3 -40.5   230   52   27   8.0   4.4   25.7  78.3    15.7      M    M
 26000  -38.0 -36.4   235   50   26   7.4   4.1   25.0  77.0    15.3      M    M
 25000  -35.7 -32.3   240   47   24   7.4   4.1   24.1  75.3    14.7      M    M
 24000  -33.5 -28.3   245   44   23   7.4   4.1   23.2  73.8    14.3      M    M
 23000  -31.2 -24.2   250   42   22   8.2   4.5   22.5  72.6    13.8      M    M
 22000  -28.8 -19.8   250   41   21   8.2   4.5   21.9  71.4    13.5      M    M
 21000  -26.4 -15.5   250   40   21   8.2   4.5   21.4  70.5    13.2      M    M
 20000  -24.0 -11.2   255   39   20   7.9   4.3   20.8  69.4    12.8      M    M
 19500  -22.8  -9.0   255   38   19   7.9   4.3   20.4  68.7    12.5      M    M
 19000  -21.6  -6.9   255   37   19   7.9   4.3   20.1  68.2    12.3      M    M
 18500  -20.5  -4.9   255   36   19   7.9   4.3   19.8  67.6    12.1      M    M
 18000  -19.3  -2.7   255   36   18   7.8   4.3   19.5  67.1    11.9      M    M
 17500  -18.2  -0.8   255   34   18   7.5   4.1   19.1  66.4    11.7      M    M
 17000  -17.1   1.2   255   33   17   7.6   4.1   18.7  65.7    11.4      M    M
 16500  -16.0   3.2   255   31   16   7.4   4.1   18.4  65.1    11.1      M    M
 16000  -14.9   5.2   255   29   15   7.4   4.1   18.0  64.3    10.8      M    M
 15500  -13.8   7.2   250   27   14   7.4   4.1   17.6  63.6    10.5      M    M
 15000  -12.7   9.1   250   24   12   7.4   4.1   17.2  62.9    10.1      M    M
 14500  -11.1  12.0   240   21   11   7.4   4.0   16.6  61.9     9.7      M    M
 14000  -10.0  14.0   235   19   10   7.3   4.0   16.2  61.2     9.4      M    M
 13500   -8.9  16.0   230   17    9   7.8   4.3   15.8  60.5     9.1      M    M
 13000   -7.7  18.1   220   15    8   7.9   4.4   15.5  60.0     8.8      M    M
 12500   -6.5  20.3   210   14    7   7.8   4.3   15.3  59.5     8.6      M    M
 12000   -5.4  22.3   210   13    7   7.7   4.2   14.9  58.8     8.3      M    M
 11500   -4.3  24.3   210   12    6   7.8   4.3   14.6  58.3     8.0      M    M
 11000   -3.1  26.4   205   12    6   8.0   4.4   14.3  57.7     7.8      M    M
 10500   -1.9  28.6   205   11    6   8.3   4.6   14.0  57.2     7.6      M    M
 10250   -1.3  29.7   205   10    5   8.3   4.5   13.9  57.1     7.5      M    M
 10000   -0.7  30.7   210   10    5   6.9   3.8   13.8  56.8     7.4      M    M
  9750   -0.2  31.6   210    9    5   6.4   3.5   13.5  56.3     7.1      M    M
  9500    0.3  32.5   215    9    5   6.3   3.4   13.2  55.8     6.9      M    M
  9250    0.7  33.3   225    8    4   6.4   3.5   13.0  55.3     6.7      M    M
  9000    1.2  34.2   235    8    4   5.2   2.9   12.7  54.8     6.4      M    M
  8750    1.5  34.7   240    8    4   3.9   2.1   12.3  54.1     6.0      M    M
  8500    1.8  35.2   245    7    4   4.2   2.3   11.8  53.3     5.6      M    M
  8250    2.1  35.8   255    8    4   4.4   2.4   11.4  52.5     5.2      M    M
  8000    2.5  36.5   265    8    4   3.8   2.1   11.0  51.7     4.8      M    M
  7750    2.7  36.9   275    9    4   2.0   1.1   10.4  50.8     4.3      M    M
  7500    2.8  37.0   280    9    4   1.5   0.8    9.8  49.7     3.7      M    M
  7250    2.9  37.2   290    9    5   1.6   0.9    9.2  48.5     3.1      M    M
  7000    3.1  37.6   295    9    5   2.1   1.1    8.6  47.4     2.5      M    M
  6750    3.2  37.8   305   10    5  -0.2  -0.1    8.0  46.3     1.9      M    M
  6500    3.0  37.4   300    9    5  -2.8  -1.5    7.0  44.7     1.0      M    M
  6250    2.8  37.0   300    8    4  -1.2  -0.6    6.2  43.1     0.1      M    M
  6000    2.7  36.9   295    7    4  -5.2  -2.8    5.3  41.5    -0.8    119  0.6
  5750    1.9  35.4   275    5    2 -12.1  -6.6    3.9  38.9    -2.2    134  0.7
  5500    0.9  33.6   240    3    2 -12.1  -6.7    2.2  36.0    -3.9    157  0.8

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

           12/25/2014 at 0800 MST          |       12/25/2014 at 1100 MST
                                           |
K index... +14.4  LI... +1.6               | K index... +14.4  LI... +2.4
CAPE... 0.0  CIN... -1.2                   | 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 -54.8 -66.6  240  32 16   3.5   1.9 | -54.7 -66.5  235  37 19   4.1   2.2
 45000 -49.5 -57.1  255  37 19   3.5   1.9 | -48.6 -55.5  250  56 29   4.0   2.2
 40000 -54.3 -65.7  240  59 30  -4.1  -2.2 | -52.2 -62.0  235  62 32  -3.2  -1.8
 38000 -56.0 -68.8  235  67 35   3.7   2.0 | -53.6 -64.5  230  64 33   2.9   1.6
 36000 -54.1 -65.4  235  65 34   3.2   1.8 | -52.1 -61.8  225  63 32   2.5   1.4
 34000 -52.2 -62.0  230  63 33   3.2   1.8 | -50.6 -59.1  225  61 31   2.5   1.4
 32000 -49.7 -57.5  230  61 32   4.3   2.3 | -49.1 -56.4  225  61 31   2.4   1.3
 30000 -47.2 -53.0  235  60 31   4.2   2.3 | -47.7 -53.9  230  61 32   2.5   1.4
 29000 -45.5 -49.9  235  57 29   6.4   3.5 | -46.3 -51.3  230  60 31   6.5   3.6
 28000 -43.1 -45.6  235  52 27   6.4   3.5 | -43.8 -46.8  230  57 29   6.7   3.7
 27000 -41.2 -42.2  235  48 25   6.4   3.5 | -41.8 -43.2  235  55 28   6.7   3.7
 26000 -39.2 -38.6  235  45 23   7.4   4.0 | -39.5 -39.1  230  51 26   9.3   5.1
 25000 -37.0 -34.6  235  44 22   7.3   4.0 | -36.8 -34.2  230  46 24   9.1   5.0
 24000 -34.8 -30.6  240  42 22   7.3   4.0 | -34.1 -29.4  225  41 21   9.1   5.0
 23000 -32.5 -26.5  245  41 21   8.9   4.9 | -31.5 -24.7  220  36 19   7.0   3.8
 22000 -29.9 -21.8  250  40 20   8.7   4.8 | -29.3 -20.7  220  32 17   7.2   3.9
 21000 -27.3 -17.1  250  38 20   8.7   4.8 | -27.2 -17.0  220  28 15   7.2   3.9
 20000 -24.9 -12.8  255  37 19   7.6   4.2 | -25.2 -13.4  220  25 13   6.0   3.3
 19500 -23.8 -10.8  255  37 19   7.6   4.1 | -24.3 -11.7  220  23 12   6.0   3.3
 19000 -22.7  -8.9  255  36 19   7.6   4.2 | -23.4 -10.1  225  22 11   6.0   3.3
 18500 -21.5  -6.7  255  36 18   7.6   4.2 | -22.5  -8.5  225  20 10   6.1   3.3
 18000 -20.4  -4.7  255  35 18   7.8   4.3 | -21.6  -6.9  225  19 10   6.2   3.4
 17500 -19.2  -2.6  255  34 17   8.3   4.6 | -20.6  -5.1  225  19 10   7.4   4.0
 17000 -18.0  -0.4  250  33 17   8.4   4.6 | -19.6  -3.3  225  18 10   7.3   4.0
 16500 -16.8   1.8  250  31 16   8.1   4.4 | -18.5  -1.3  225  18 10   7.4   4.1
 16000 -15.6   3.9  250  28 15   8.1   4.4 | -17.4   0.7  225  19 10   7.4   4.1
 15500 -14.4   6.1  250  26 13   7.7   4.2 | -16.3   2.7  220  19 10   7.5   4.1
 15000 -13.3   8.1  245  22 12   7.4   4.1 | -15.2   4.6  220  19 10   7.5   4.1
 14500 -12.2  10.0  245  19 10   7.3   4.0 | -14.1   6.6  215  19 10   7.6   4.1
 14000 -10.7  12.7  235  16  8   7.1   3.9 | -12.4   9.7  215  19 10   7.8   4.3
 13500  -9.6  14.7  230  15  8   7.5   4.1 | -11.2  11.8  215  19 10   7.4   4.1
 13000  -8.5  16.7  215  14  7   7.8   4.3 | -10.2  13.6  215  17  9   7.0   3.8
 12500  -7.3  18.9  205  14  7   7.8   4.3 |  -9.2  15.4  210  14  7   6.2   3.4
 12000  -6.2  20.8  205  13  7   7.7   4.2 |  -8.4  16.9  205  11  6   5.1   2.8
 11500  -5.0  23.0  200  12  6   6.6   3.6 |  -7.7  18.1  195   8  4   5.4   3.0
 11000  -4.3  24.3  200   9  5   5.1   2.8 |  -6.8  19.8  170   6  3   6.1   3.4
 10500  -3.6  25.5  190   6  3   5.3   2.9 |  -5.9  21.4  145   6  3   7.9   4.3
 10250  -3.1  26.4  180   4  2   5.6   3.1 |  -5.2  22.6  140   6  3  10.2   5.6
 10000  -2.7  27.1  160   3  2   5.1   2.8 |  -4.5  23.9  140   5  3   7.4   4.1
  9750  -2.4  27.7  145   3  2   4.5   2.5 |  -4.1  24.6  135   4  2   6.0   3.3
  9500  -2.0  28.4  130   3  2   5.8   3.2 |  -3.6  25.5  135   2  1   6.2   3.4
  9250  -1.5  29.3  110   2  1   7.3   4.0 |  -3.1  26.4  115   1  1   6.0   3.3
  9000  -1.0  30.2  065   1  1   5.7   3.1 |  -2.7  27.1  040   1  0   5.8   3.2
  8750  -0.7  30.7  360   1  1   4.1   2.3 |  -2.3  27.9  005   2  1   5.5   3.0
  8500  -0.3  31.5  325   2  1   4.9   2.7 |  -1.8  28.8  360   3  1   6.2   3.4
  8250   0.1  32.2  310   4  2   5.6   3.1 |  -1.4  29.5  355   4  2   6.9   3.8
  8000   0.5  32.9  305   6  3   4.7   2.6 |  -0.9  30.4  355   5  3   5.7   3.1
  7750   0.7  33.3  300   8  4   2.2   1.2 |  -0.5  31.1  350   6  3   4.1   2.3
  7500   0.8  33.4  300   8  4   1.2   0.7 |  -0.2  31.6  350   7  3   4.7   2.6
  7250   0.9  33.6  295   8  4   1.6   0.9 |   0.2  32.4  345   7  3   5.1   2.8
  7000   1.1  34.0  295   8  4   1.5   0.8 |   0.6  33.1  345   7  3   5.3   2.9
  6750   1.2  34.2  295   9  4   2.1   1.2 |   1.0  33.8  345   6  3   4.5   2.5
  6500   1.3  34.3  295   7  3   2.0   1.1 |   1.2  34.2  350   4  2   3.7   2.0
  6250   1.5  34.7  290   5  3   3.3   1.8 |   1.5  34.7  355   3  1   3.6   2.0
  6000   1.7  35.1  280   3  2  -1.8  -1.0 |   1.8  35.2  020   1  1   4.8   2.6
  5750   1.0  33.8  245   4  2 -14.4  -7.9 |   2.3  36.1  000   0  0  10.4   5.7
  5500  -0.4  31.3  215   4  2 -19.7 -10.8 |   3.3  37.9  000   0  0  15.8   8.7

           12/25/2014 at 1400 MST          |       12/25/2014 at 1700 MST
                                           |
K index... +13.9  LI... +2.7               | K index... +17.4  LI... +3.0
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -2.5
                                           |
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 -55.0 -67.0  235  27 14   4.4   2.4 | -55.3 -67.5  245  27 14   3.3   1.8
 45000 -48.5 -55.3  250  24 13   4.3   2.4 | -50.3 -58.5  250  24 13   3.3   1.8
 40000 -51.3 -60.3  230  58 30  -2.9  -1.6 | -50.1 -58.2  230  54 28  -0.3  -0.2
 38000 -52.9 -63.2  225  73 38   1.2   0.7 | -50.3 -58.5  230  68 35   0.4   0.2
 36000 -51.6 -60.9  225  72 37   2.1   1.2 | -50.0 -58.0  225  69 36   0.5   0.3
 34000 -50.1 -58.2  225  71 37   2.1   1.2 | -49.7 -57.5  225  71 36   0.5   0.3
 32000 -48.3 -54.9  225  69 36   3.3   1.8 | -48.5 -55.3  225  69 36   2.3   1.3
 30000 -46.3 -51.3  225  68 35   3.3   1.8 | -47.1 -52.8  220  67 34   2.3   1.3
 29000 -45.0 -49.0  225  65 33   5.0   2.7 | -46.0 -50.8  220  63 32   4.6   2.5
 28000 -43.5 -46.3  225  61 32   5.0   2.7 | -44.7 -48.5  220  56 29   4.6   2.5
 27000 -42.0 -43.6  230  58 30   5.0   2.7 | -43.3 -45.9  220  50 26   4.6   2.5
 26000 -40.4 -40.7  230  54 28   7.0   3.8 | -41.8 -43.2  225  45 23   7.3   4.0
 25000 -38.2 -36.8  230  50 26   7.4   4.0 | -39.4 -38.9  225  43 22   8.0   4.4
 24000 -36.0 -32.8  225  46 24   7.4   4.1 | -36.9 -34.4  225  42 22   8.0   4.4
 23000 -33.8 -28.8  225  43 22   7.7   4.2 | -34.5 -30.1  225  41 21   8.1   4.4
 22000 -31.4 -24.5  225  41 21   7.8   4.3 | -32.1 -25.8  230  41 21   8.1   4.4
 21000 -29.1 -20.4  220  40 21   7.8   4.3 | -29.7 -21.5  230  41 21   8.1   4.4
 20000 -26.8 -16.2  220  38 20   6.2   3.4 | -27.4 -17.3  230  40 20   5.7   3.1
 19500 -25.9 -14.6  225  37 19   6.3   3.5 | -26.5 -15.7  235  36 19   6.0   3.3
 19000 -25.0 -13.0  225  36 19   6.4   3.5 | -25.6 -14.1  235  33 17   6.0   3.3
 18500 -24.0 -11.2  230  35 18   6.4   3.5 | -24.8 -12.6  235  30 15   6.1   3.3
 18000 -23.1  -9.6  235  34 18   6.4   3.5 | -23.9 -11.0  240  26 14   6.2   3.4
 17500 -22.1  -7.8  240  34 18   6.0   3.3 | -23.0  -9.4  240  24 12   5.3   2.9
 17000 -20.8  -5.4  245  37 19   6.1   3.4 | -22.2  -8.0  250  23 12   5.5   3.0
 16500 -19.7  -3.5  245  38 19   8.3   4.5 | -21.4  -6.5  255  23 12   6.4   3.5
 16000 -18.5  -1.3  250  38 19   8.1   4.4 | -19.9  -3.8  245  23 12   6.9   3.8
 15500 -17.3   0.9  250  37 19   8.8   4.8 | -18.9  -2.0  245  22 12   6.6   3.6
 15000 -16.0   3.2  250  35 18   8.9   4.9 | -17.9  -0.2  240  21 11   6.5   3.6
 14500 -14.7   5.5  250  32 17   7.6   4.1 | -17.0   1.4  240  19 10   6.2   3.4
 14000 -13.7   7.3  250  27 14   6.7   3.7 | -16.1   3.0  235  15  8   6.1   3.3
 13500 -12.7   9.1  255  22 11   6.0   3.3 | -15.2   4.6  230  12  6   6.5   3.6
 13000 -12.0  10.4  255  17  9   5.1   2.8 | -14.2   6.4  225  10  5   7.0   3.9
 12500 -11.2  11.8  260  12  6   5.1   2.8 | -13.2   8.2  220   7  4   6.6   3.6
 12000 -10.5  13.1  260   8  4   5.1   2.8 | -12.3   9.9  215   6  3   5.9   3.2
 11500  -9.8  14.4  265   4  2   5.5   3.0 | -11.4  11.5  210   5  3   6.4   3.5
 11000  -8.8  16.2  295   3  1   6.5   3.6 | -10.4  13.3  205   6  3   7.3   4.0
 10500  -7.9  17.8  340   3  1   6.6   3.6 |  -9.3  15.3  200   7  4   6.8   3.8
 10250  -7.4  18.7  355   3  2   6.7   3.7 |  -8.8  16.2  185   7  4   5.9   3.3
 10000  -6.9  19.6  010   4  2   7.0   3.8 |  -8.4  16.9  170   8  4   6.6   3.6
  9750  -6.4  20.5  020   4  2   7.1   3.9 |  -7.9  17.8  155   9  5   7.2   4.0
  9500  -5.8  21.6  030   5  3   7.3   4.0 |  -7.4  18.7  145  11  5   5.9   3.2
  9250  -5.3  22.5  045   6  3   7.9   4.3 |  -7.0  19.4  130  11  5   5.1   2.8
  9000  -4.7  23.5  055   7  4   6.6   3.6 |  -6.6  20.1  120  11  6   5.0   2.7
  8750  -4.3  24.3  060   8  4   5.0   2.8 |  -6.3  20.7  110  11  6   4.4   2.4
  8500  -3.9  25.0  065   9  5   6.3   3.4 |  -6.0  21.2  100  11  6   4.2   2.3
  8250  -3.4  25.9  070  10  5   7.9   4.3 |  -5.6  21.9  085  11  6   5.1   2.8
  8000  -2.8  27.0  075  11  6   5.7   3.1 |  -5.3  22.5  070  12  6   2.5   1.4
  7750  -2.5  27.5  080  12  6   5.4   3.0 |  -5.1  22.8  060  13  7   4.4   2.4
  7500  -2.0  28.4  085  12  6   9.0   4.9 |  -4.6  23.7  065  14  7   8.6   4.7
  7250  -1.2  29.8  085  12  6   9.9   5.4 |  -4.0  24.8  070  14  7   7.6   4.2
  7000  -0.5  31.1  085  12  6   9.6   5.3 |  -3.5  25.7  075  14  7   8.1   4.5
  6750   0.2  32.4  080  12  6   9.9   5.4 |  -2.9  26.8  080  13  7   8.0   4.4
  6500   0.9  33.6  080  12  6  10.0   5.5 |  -2.3  27.9  085  13  6   7.7   4.2
  6250   1.7  35.1  080  12  6  10.2   5.6 |  -1.7  28.9  095  12  6   7.9   4.3
  6000   2.5  36.5  080  12  6   9.1   5.0 |  -1.2  29.8  100  11  6   7.5   4.1
  5750   3.1  37.6  080  11  6  11.2   6.2 |  -0.6  30.9  100  10  5   9.1   5.0
  5500   4.2  39.6  080  10  5  18.3  10.0 |   0.2  32.4  100   8  4  12.7   6.9
________________________________________________________________________________

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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