Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 131227
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0626 MDT Sunday, April 13, 2014

This forecast is for Sunday, April 13, 2014:

If the trigger temperature of 45.6 F/7.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5285 ft MSL (0 ft AGL)

Forecast maximum temperature................... 36.0 F/2.7 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 Monday 04/14....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Remaining poor
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 16584 ft MSL (11299 ft AGL)
Wave soaring outlook for Monday 04/14.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:24:55 / 19:34:44 MDT
Total possible sunshine........... 13 hr 9 min 50 sec (789 min 50 sec)
Altitude of sun at 12:59:59 MDT... 59.46 degrees

Upper air data from rawinsonde observation taken on 04/13/2014 at 0600 MDT

Freezing level.................. 6705 ft MSL (1420 ft AGL)
Convective condensation level... 9086 ft MSL (3801 ft AGL)
Lifted condensation level....... 7100 ft MSL (1814 ft AGL)
Lifted index.................... +11.2
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  -57.6 -71.7   275   33   17   4.7   2.6  104.5 220.0    58.4      M    M
 45000  -55.1 -67.2   260   55   28   2.8   1.5   83.9 183.1    49.9      M    M
 40000  -53.1 -63.6   240   34   18   3.3   1.8   62.9 145.3    39.8      M    M
 38000  -55.0 -67.0   270   24   12 -13.5  -7.4   51.2 124.2    33.0      M    M
 36000  -53.3 -63.9   270   16    8   6.3   3.5   45.2 113.4    29.7      M    M
 34000  -56.1 -69.0   275   18    9 -14.1  -7.7   33.0  91.3    21.8      M    M
 32000  -53.2 -63.8   215   14    7   7.9   4.3   28.8  83.8    19.3      M    M
 30000  -47.5 -53.5   235   13    7   9.3   5.1   28.5  83.3    19.6      M    M
 29000  -44.8 -48.6   240   14    7   9.2   5.1   28.3  83.0    19.8      M    M
 28000  -41.3 -42.3   240   11    5   9.2   5.1   28.0  82.4    19.8      M    M
 27000  -38.6 -37.5   240    8    4   9.1   5.0   27.8  82.1    20.0      M    M
 26000  -36.1 -33.0   240    5    3   7.9   4.3   27.2  81.0    19.7      M    M
 25000  -33.7 -28.7   235    8    4   8.4   4.6   26.7  80.1    19.5      M    M
 24000  -31.1 -24.0   255   12    6   9.1   5.0   26.3  79.3    19.4      M    M
 23000  -28.6 -19.5   265   13    7   8.9   4.9   25.9  78.5    19.3      M    M
 22000  -26.0 -14.8   275   13    7   7.8   4.3   25.4  77.7    19.1      M    M
 21000  -23.9 -11.0   280   14    7   7.3   4.0   24.5  76.1    18.6      M    M
 20000  -21.7  -7.1   275   20   10   7.7   4.2   23.7  74.6    18.1      M    M
 19500  -20.5  -4.9   275   20   10   7.5   4.1   23.3  73.9    17.8      M    M
 19000  -19.5  -3.1   270   21   11   6.7   3.6   22.8  73.0    17.5      M    M
 18500  -18.5  -1.3   270   21   11   6.7   3.7   22.2  72.0    17.1      M    M
 18000  -17.5   0.5   260   23   12   7.5   4.1   21.8  71.2    16.8      M    M
 17500  -16.4   2.5   260   25   13   7.4   4.1   21.4  70.5    16.5      M    M
 17000  -15.3   4.5   260   25   13   7.5   4.1   21.0  69.8    16.2      M    M
 16500  -14.1   6.6   265   26   13   9.0   4.9   20.7  69.3    16.1      M    M
 16000  -12.8   9.0   265   27   14   8.4   4.6   20.6  69.1    16.0      M    M
 15500  -11.8  10.8   265   25   13   5.9   3.2   20.1  68.2    15.6      M    M
 15000  -11.0  12.2   260   23   12   6.0   3.3   19.5  67.0    15.1      M    M
 14500  -10.1  13.8   260   21   11   6.0   3.3   18.9  66.0    14.6      M    M
 14000   -8.8  16.2   255   17    9   6.1   3.3   18.0  64.4    13.9      M    M
 13500   -7.9  17.8   265   15    8   6.1   3.3   17.4  63.3    13.4      M    M
 13000   -7.0  19.4   270   13    7   6.1   3.3   16.8  62.2    12.9      M    M
 12500   -6.1  21.0   260   10    5   6.1   3.3   16.2  61.1    12.3      M    M
 12000   -5.3  22.5   250    6    3   6.2   3.4   15.6  60.1    11.8      M    M
 11500   -4.7  23.5   240    3    1   2.3   1.3   14.7  58.4    11.0      M    M
 11000   -4.3  24.3   120    1    1   3.8   2.1   13.5  56.4    10.0      M    M
 10500   -4.7  23.5   085    4    2  -9.2  -5.1   11.6  52.9     8.2      M    M
 10250   -5.1  22.8   080    6    3  -1.6  -0.9   10.3  50.6     7.1      M    M
 10000   -5.0  23.0   080    8    4   1.8   1.0    9.7  49.4     6.5      M    M
  9750   -4.9  23.2   075   10    5   1.3   0.7    9.0  48.2     5.9      M    M
  9500   -4.7  23.5   065   12    6   4.0   2.2    8.4  47.2     5.3      M    M
  9250   -4.4  24.1   055   14    7   4.8   2.6    8.0  46.5     5.0      M    M
  9000   -4.0  24.8   050   16    8   4.6   2.5    7.6  45.8     4.6      M    M
  8750   -3.7  25.3   050   17    9   4.6   2.5    7.2  45.0     4.2      M    M
  8500   -3.3  26.1   050   18    9   4.7   2.6    6.8  44.3     3.8      M    M
  8250   -3.0  26.6   050   19   10   4.5   2.5    6.4  43.6     3.4      M    M
  8000   -2.7  27.1   050   20   10   5.9   3.3    6.1  42.9     3.1      M    M
  7750   -2.1  28.2   050   18    9   7.3   4.0    5.8  42.5     2.9      M    M
  7500   -1.6  29.1   050   16    8   6.9   3.8    5.6  42.1     2.7      M    M
  7250   -1.1  30.0   050   15    8   7.0   3.8    5.4  41.8     2.4      M    M
  7000   -0.6  30.9   050   13    7   7.0   3.8    5.2  41.4     2.2      M    M
  6750   -0.1  31.8   040   13    7   6.9   3.8    5.0  41.0     2.0      M    M
  6500    0.4  32.7   035   13    7   7.2   3.9    4.8  40.6     1.8      M    M
  6250    0.9  33.6   025   14    7   6.3   3.5    4.6  40.2     1.6      M    M
  6000    1.4  34.5   020   15    8   9.5   5.2    4.4  39.9     1.4      M    M
  5750    2.4  36.3   025   13    7  15.6   8.6    4.6  40.3     1.6      M    M
  5500    3.6  38.5   035   11    6  16.3   9.0    5.1  41.2     2.1      M    M

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

           04/13/2014 at 0900 MDT          |       04/13/2014 at 1200 MDT
                                           |
K index... +13.0  LI... +7.6               | K index... +9.1  LI... +9.1
CAPE... 0.0  CIN... M                      | CAPE... +38.7  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 -56.1 -69.0  275  33 17   1.7   0.9 | -55.6 -68.1  280  33 17   2.4   1.3
 45000 -53.6 -64.5  270  41 21   1.8   1.0 | -51.7 -61.1  270  43 22   2.2   1.2
 40000 -51.9 -61.4  265  36 19   1.0   0.5 | -50.5 -58.9  265  43 22   0.8   0.4
 38000 -52.1 -61.8  265  35 18  -2.8  -1.5 | -50.7 -59.3  260  43 22  -2.7  -1.5
 36000 -53.7 -64.7  260  35 18  -2.8  -1.5 | -52.4 -62.3  255  43 22  -2.8  -1.5
 34000 -55.4 -67.7  260  35 18  -0.7  -0.4 | -54.0 -65.2  250  42 22  -2.6  -1.5
 32000 -52.1 -61.8  250  27 14   6.1   3.3 | -51.8 -61.2  245  39 20   4.4   2.4
 30000 -48.4 -55.1  235  20 10   7.5   4.1 | -48.6 -55.5  235  36 19   8.5   4.7
 29000 -45.7 -50.3  235  19 10   9.1   5.0 | -45.9 -50.6  235  36 18   9.1   5.0
 28000 -42.3 -44.1  230  19 10   9.1   5.0 | -43.2 -45.8  235  36 18   9.1   5.0
 27000 -39.6 -39.3  225  19 10   9.1   5.0 | -40.4 -40.7  235  35 18   9.1   5.0
 26000 -36.9 -34.4  225  19 10   8.9   4.9 | -37.8 -36.0  235  35 18   8.9   4.9
 25000 -34.3 -29.7  235  20 10   8.9   4.9 | -35.1 -31.2  240  34 17   8.9   4.9
 24000 -31.6 -24.9  240  21 11   9.0   4.9 | -32.4 -26.3  240  33 17   8.9   4.9
 23000 -29.0 -20.2  245  22 11   8.5   4.7 | -29.8 -21.6  240  32 16   8.7   4.7
 22000 -26.5 -15.7  250  24 12   8.5   4.7 | -27.2 -17.0  245  30 16   8.7   4.8
 21000 -24.0 -11.2  255  26 13   8.5   4.6 | -24.7 -12.5  250  29 15   8.7   4.8
 20000 -21.7  -7.1  265  27 14   7.6   4.2 | -22.3  -8.1  250  26 14   7.9   4.3
 19500 -20.6  -5.1  265  28 14   7.6   4.2 | -21.1  -6.0  250  25 13   7.9   4.3
 19000 -19.4  -2.9  265  28 15   7.6   4.2 | -20.0  -4.0  255  23 12   7.9   4.3
 18500 -18.3  -0.9  270  29 15   7.6   4.2 | -18.8  -1.8  255  22 11   8.0   4.4
 18000 -17.2   1.0  270  29 15   7.8   4.3 | -17.7   0.1  260  20 10   7.1   3.9
 17500 -16.0   3.2  270  29 15   7.8   4.3 | -16.6   2.1  260  20 10   7.1   3.9
 17000 -14.9   5.2  275  29 15   7.5   4.1 | -15.6   3.9  265  19 10   7.2   3.9
 16500 -13.9   7.0  275  27 14   7.1   3.9 | -14.5   5.9  270  19 10   7.3   4.0
 16000 -12.8   9.0  275  26 14   7.1   3.9 | -13.4   7.9  270  19 10   7.3   4.0
 15500 -11.9  10.6  270  25 13   6.0   3.3 | -12.4   9.7  270  19 10   7.3   4.0
 15000 -11.0  12.2  270  24 12   6.3   3.4 | -10.8  12.6  270  20 10   6.5   3.5
 14500 -10.0  14.0  265  21 11   3.3   1.8 | -10.1  13.8  270  20 10   4.3   2.3
 14000  -9.6  14.7  260  20 10   3.1   1.7 |  -9.4  15.1  265  21 11   4.2   2.3
 13500  -9.4  15.1  260  18  9   0.2   0.1 |  -9.2  15.4  260  21 11  -0.1  -0.0
 13000  -9.3  15.3  260  16  8   0.5   0.3 |  -9.2  15.4  255  20 10   0.7   0.4
 12500  -9.4  15.1  260  14  7  -1.5  -0.8 |  -9.5  14.9  255  18  9  -4.7  -2.6
 12000  -9.5  14.9  260  11  6  -1.7  -0.9 | -10.1  13.8  255  15  8  -4.7  -2.6
 11500  -9.4  15.1  265   8  4   3.9   2.2 | -10.4  13.3  255  11  6   0.5   0.3
 11000  -8.9  16.0  265   5  3   3.4   1.9 | -10.4  13.3  260   6  3  -0.2  -0.1
 10500  -8.3  17.1  290   1  0   4.6   2.5 | -10.0  14.0  295   2  1   5.4   3.0
 10250  -8.0  17.6  060   2  1   4.3   2.3 |  -9.6  14.7  045   2  1   4.4   2.4
 10000  -7.6  18.3  070   4  2   5.0   2.8 |  -9.3  15.3  065   4  2   5.7   3.1
  9750  -7.3  18.9  065   8  4   4.6   2.5 |  -8.8  16.2  070   8  4   5.7   3.1
  9500  -7.0  19.4  065  11  6   3.6   2.0 |  -8.5  16.7  070  11  6   4.7   2.6
  9250  -6.7  19.9  065  14  7   4.0   2.2 |  -8.1  17.4  070  14  7   5.0   2.7
  9000  -6.4  20.5  060  17  9   3.3   1.8 |  -7.7  18.1  070  16  8   4.7   2.6
  8750  -6.2  20.8  060  19 10   3.8   2.1 |  -7.4  18.7  070  16  8   5.3   2.9
  8500  -5.8  21.6  055  20 10   4.8   2.6 |  -7.0  19.4  065  15  8   5.8   3.2
  8250  -5.5  22.1  050  21 11   4.5   2.5 |  -6.6  20.1  060  15  8   5.7   3.1
  8000  -5.2  22.6  050  22 11   5.4   3.0 |  -6.1  21.0  060  14  7   6.8   3.7
  7750  -4.7  23.5  045  22 11   5.6   3.1 |  -5.5  22.1  050  12  6   8.4   4.6
  7500  -4.4  24.1  045  21 11   4.6   2.6 |  -4.9  23.2  050  11  6   8.4   4.6
  7250  -4.0  24.8  040  20 10   6.1   3.3 |  -4.3  24.3  040  10  5   9.6   5.3
  7000  -3.5  25.7  035  19 10   8.0   4.4 |  -3.5  25.7  035   9  5  11.8   6.5
  6750  -2.9  26.8  030  18  9   8.0   4.4 |  -2.7  27.1  030   9  5  10.3   5.7
  6500  -2.3  27.9  025  16  8   8.3   4.6 |  -2.0  28.4  030   9  4   9.5   5.2
  6250  -1.7  28.9  020  15  8  10.0   5.5 |  -1.2  29.8  030   8  4  11.4   6.2
  6000  -0.9  30.4  015  14  7  10.9   6.0 |  -0.3  31.5  025   8  4  11.9   6.5
  5750  -0.1  31.8  010  13  7  10.2   5.6 |   0.5  32.9  025   8  4  11.7   6.4
  5500   0.7  33.3  010  12  6  13.2   7.2 |   1.5  34.7  025   7  4  17.1   9.4

           04/13/2014 at 1500 MDT          |       04/13/2014 at 1800 MDT
                                           |
K index... +10.5  LI... +8.1               | K index... +8.2  LI... +10.3
CAPE... +23.9  CIN... -0.7                 | CAPE... 0.0  CIN... -1.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -55.3 -67.5  280  35 18   3.0   1.6 | -55.2 -67.4  285  34 18   3.1   1.7
 45000 -50.6 -59.1  275  41 21   2.7   1.5 | -50.4 -58.7  280  40 21   3.0   1.6
 40000 -48.7 -55.7  265  39 20   1.2   0.7 | -47.5 -53.5  270  34 18   1.9   1.0
 38000 -48.8 -55.8  260  40 20  -3.3  -1.8 | -47.2 -53.0  260  35 18  -3.6  -2.0
 36000 -50.8 -59.4  250  43 22  -3.3  -1.8 | -49.5 -57.1  250  43 22  -3.7  -2.0
 34000 -52.8 -63.0  245  48 25  -4.1  -2.3 | -51.7 -61.1  245  52 27  -4.1  -2.2
 32000 -51.4 -60.5  240  44 23   3.2   1.8 | -51.2 -60.2  240  52 27   1.8   1.0
 30000 -49.1 -56.4  235  39 20   7.4   4.0 | -49.9 -57.8  230  51 26   5.2   2.9
 29000 -46.4 -51.5  235  38 20   9.3   5.1 | -47.2 -53.0  230  50 26   9.2   5.0
 28000 -43.6 -46.5  235  37 19   9.3   5.1 | -44.5 -48.1  230  48 25   9.2   5.0
 27000 -40.8 -41.4  235  36 18   9.3   5.1 | -41.8 -43.2  235  46 24   9.2   5.0
 26000 -38.2 -36.8  235  34 17   8.5   4.7 | -39.1 -38.4  235  43 22   8.5   4.6
 25000 -35.6 -32.1  240  31 16   8.5   4.7 | -36.6 -33.9  235  38 20   8.5   4.6
 24000 -33.1 -27.6  240  29 15   8.5   4.7 | -34.1 -29.4  240  33 17   8.4   4.6
 23000 -30.6 -23.1  245  28 14   8.1   4.4 | -31.6 -24.9  240  28 15   8.0   4.4
 22000 -28.2 -18.8  250  28 14   8.1   4.4 | -29.2 -20.6  245  24 12   8.0   4.4
 21000 -25.8 -14.4  255  28 14   8.1   4.5 | -26.9 -16.4  250  19 10   8.0   4.4
 20000 -23.5 -10.3  255  29 15   7.7   4.2 | -24.5 -12.1  255  17  9   8.0   4.4
 19500 -22.4  -8.3  255  29 15   7.7   4.2 | -23.3  -9.9  255  17  9   8.0   4.4
 19000 -21.2  -6.2  255  29 15   7.7   4.2 | -22.1  -7.8  260  17  9   8.0   4.4
 18500 -20.1  -4.2  255  30 15   7.8   4.3 | -20.9  -5.6  260  17  9   8.0   4.4
 18000 -18.9  -2.0  255  30 15   7.6   4.2 | -19.8  -3.6  260  17  9   7.7   4.2
 17500 -17.8  -0.0  250  31 16   7.5   4.1 | -18.7  -1.7  260  18  9   7.5   4.1
 17000 -16.7   1.9  250  31 16   7.2   4.0 | -17.5   0.5  255  19 10   7.2   3.9
 16500 -15.7   3.7  245  31 16   6.5   3.6 | -16.6   2.1  250  20 10   5.7   3.1
 16000 -14.8   5.4  245  31 16   6.8   3.7 | -15.8   3.6  250  21 11   6.0   3.3
 15500 -13.7   7.3  240  30 16   4.0   2.2 | -15.1   4.8  245  21 11   3.0   1.6
 15000 -13.1   8.4  235  29 15   3.3   1.8 | -14.5   5.9  245  20 10   2.6   1.4
 14500 -13.0   8.6  235  26 13   0.2   0.1 | -14.5   5.9  245  18  9  -1.9  -1.0
 14000 -12.9   8.8  235  22 11   0.3   0.2 | -14.7   5.5  245  16  8  -1.6  -0.9
 13500 -13.0   8.6  235  16  8  -1.4  -0.8 | -14.9   5.2  250  13  7  -1.6  -0.9
 13000 -13.1   8.4  245  10  5  -1.7  -1.0 | -15.1   4.8  260  10  5  -2.2  -1.2
 12500 -12.9   8.8  260   5  3   4.5   2.5 | -15.0   5.0  275   7  4   4.2   2.3
 12000 -12.3   9.9  335   2  1   3.8   2.1 | -14.5   5.9  305   5  2   3.5   1.9
 11500 -11.6  11.1  030   5  3   6.2   3.4 | -13.8   7.2  350   5  2   5.5   3.0
 11000 -10.8  12.6  040   8  4   6.0   3.3 | -13.0   8.6  015   7  4   5.3   2.9
 10500 -10.1  13.8  045  11  6   3.4   1.9 | -12.2  10.0  030  10  5   5.8   3.2
 10250  -9.8  14.4  045  13  7   3.0   1.7 | -11.8  10.8  035  12  6   6.5   3.6
 10000  -9.6  14.7  045  14  7   5.7   3.1 | -11.3  11.7  040  14  7   3.7   2.0
  9750  -9.0  15.8  045  16  8   7.3   4.0 | -11.1  12.0  040  16  8   3.7   2.1
  9500  -8.6  16.5  040  16  8   5.7   3.1 | -10.7  12.7  040  18  9   6.5   3.6
  9250  -8.1  17.4  040  16  8   6.2   3.4 | -10.3  13.5  040  21 11   5.8   3.2
  9000  -7.7  18.1  040  16  8   5.7   3.1 |  -9.8  14.4  045  24 12   5.8   3.2
  8750  -7.3  18.9  035  16  8   6.5   3.5 |  -9.4  15.1  040  26 13   5.3   2.9
  8500  -6.8  19.8  035  16  8   7.4   4.1 |  -9.0  15.8  040  27 14   5.3   2.9
  8250  -6.2  20.8  035  16  8   7.2   3.9 |  -8.7  16.3  040  28 14   5.4   3.0
  8000  -5.7  21.7  035  16  8   7.4   4.0 |  -8.2  17.2  035  28 14   6.4   3.5
  7750  -5.2  22.6  030  16  8   7.6   4.2 |  -7.7  18.1  035  26 13   6.2   3.4
  7500  -4.6  23.7  030  17  9   7.7   4.2 |  -7.3  18.9  030  24 13   5.0   2.7
  7250  -4.1  24.6  030  17  9   7.9   4.3 |  -6.9  19.6  030  23 12   6.5   3.5
  7000  -3.5  25.7  025  17  9   8.1   4.5 |  -6.4  20.5  025  21 11   7.5   4.1
  6750  -2.9  26.8  025  17  9   8.3   4.6 |  -5.9  21.4  020  20 10   7.9   4.3
  6500  -2.3  27.9  025  16  8   8.7   4.8 |  -5.2  22.6  015  19 10   9.3   5.1
  6250  -1.6  29.1  020  15  8   9.3   5.1 |  -4.5  23.9  015  17  9  10.1   5.5
  6000  -1.0  30.2  020  14  7   9.4   5.2 |  -3.8  25.2  010  16  8  10.0   5.5
  5750  -0.3  31.5  020  12  6   9.4   5.2 |  -3.1  26.4  010  15  8  11.0   6.0
  5500   0.5  32.9  015  11  5  13.7   7.5 |  -2.1  28.2  005  14  7  16.4   9.0
________________________________________________________________________________

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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