Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 170023
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1823 MDT Thursday, April 16, 2015

This forecast is for Friday, April 17, 2015:

If the trigger temperature of 48.6 F/9.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9394 ft MSL (4087 ft AGL)

Forecast maximum temperature................... 49.0 F/9.9 C
Time of trigger temperature.................... 1715 MDT
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................. 7655 ft MSL (2348 ft AGL)
Thermal soaring outlook for Saturday 04/18..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 14417 ft MSL (9110 ft AGL)
Wave soaring outlook for Saturday 04/18........ Poor

Remarks... None

Sunrise/Sunset.................... 06:19:20 / 19:38:31 MDT
Total possible sunshine........... 13 hr 19 min 11 sec (799 min 11 sec)
Altitude of sun at 12:59:05 MDT... 60.80 degrees

Upper air data from numerical model forecast valid on 04/17/2015 at 0600 MDT

Freezing level.................. 7266 ft MSL (1959 ft AGL)
Convective condensation level... 8098 ft MSL (2791 ft AGL)
Lifted condensation level....... 9115 ft MSL (3809 ft AGL)
Lifted index.................... +4.7
K index......................... +22.0

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  -56.9 -70.4   225   12    6   3.1   1.7      M     M       M      M    M
 45000  -52.1 -61.8   220   17    9   1.1   0.6      M     M       M      M    M
 40000  -50.3 -58.5   200   26   13   1.2   0.6      M     M       M      M    M
 38000  -50.8 -59.4   175   31   16  -3.1  -1.7      M     M       M      M    M
 36000  -52.7 -62.9   145   49   25  -3.1  -1.7      M     M       M      M    M
 34000  -54.0 -65.2   130   70   36   7.2   3.9      M     M       M      M    M
 32000  -48.6 -55.5   120   57   30   8.1   4.5      M     M       M      M    M
 30000  -43.6 -46.5   110   49   25   8.4   4.6   32.6  90.6    17.3      M    M
 29000  -41.1 -42.0   105   47   24   8.5   4.7   32.0  89.5    17.1      M    M
 28000  -38.5 -37.3   100   45   23   8.5   4.7   31.5  88.7    17.0      M    M
 27000  -36.0 -32.8   100   43   22   7.7   4.3   31.2  88.1    16.9      M    M
 26000  -34.0 -29.2   100   41   21   6.4   3.5   29.8  85.6    16.0      M    M
 25000  -32.1 -25.8   100   38   20   6.4   3.5   28.5  83.4    15.2      M    M
 24000  -30.2 -22.4   100   36   18   6.4   3.5   27.4  81.3    14.4      M    M
 23000  -28.3 -18.9   100   31   16   6.3   3.5   26.1  78.9    13.5      M    M
 22000  -26.4 -15.5   100   25   13   6.3   3.5   24.8  76.7    12.6      M    M
 21000  -24.6 -12.3   095   20   10   7.4   4.0   23.7  74.6    11.8      M    M
 20000  -22.1  -7.8   100   17    9   8.5   4.7   23.1  73.7    11.5      M    M
 19500  -20.8  -5.4   105   16    8   8.5   4.7   22.9  73.3    11.3      M    M
 19000  -19.5  -3.1   105   15    8   8.5   4.7   22.7  72.9    11.2      M    M
 18500  -18.3  -0.9   110   14    7   8.1   4.4   22.6  72.6    11.1      M    M
 18000  -17.3   0.9   120   13    7   6.6   3.6   22.1  71.8    10.7      M    M
 17500  -16.3   2.7   135   14    7   6.6   3.6   21.6  70.8    10.3      M    M
 17000  -14.7   5.5   150   15    8   7.2   3.9   20.8  69.5     9.7      M    M
 16500  -13.7   7.3   155   17    9   7.1   3.9   20.4  68.7     9.4      M    M
 16000  -12.6   9.3   155   18    9   7.3   4.0   20.0  67.9     9.0      M    M
 15500  -11.6  11.1   155   19   10   7.3   4.0   19.6  67.2     8.6      M    M
 15000  -10.5  13.1   155   20   10   7.2   4.0   19.2  66.5     8.3      M    M
 14500   -9.5  14.9   150   20   10   7.2   4.0   18.7  65.7     7.9      M    M
 14000   -8.4  16.9   145   21   11   7.0   3.8   18.3  65.0     7.5      M    M
 13500   -7.5  18.5   140   22   11   6.7   3.7   17.8  64.0     7.1      M    M
 13000   -6.5  20.3   130   24   12   6.3   3.4   17.3  63.2     6.6      M    M
 12500   -5.7  21.7   120   25   13   5.5   3.0   16.6  62.0     6.0      M    M
 12000   -4.9  23.2   110   28   14   4.8   2.6   16.0  60.8     5.4      M    M
 11500   -4.3  24.3   105   29   15   3.3   1.8   15.0  59.0     4.5      M    M
 11000   -3.9  25.0   095   31   16   2.9   1.6   14.0  57.1     3.5      M    M
 10500   -3.5  25.7   090   31   16   2.3   1.3   12.8  55.0     2.5      M    M
 10250   -3.3  26.1   085   31   16   2.4   1.3   12.2  53.9     1.9      M    M
 10000   -3.2  26.2   080   31   16   1.9   1.1   11.6  52.9     1.4      M    M
  9750   -3.0  26.6   080   31   16   2.0   1.1   11.0  51.8     0.8      M    M
  9500   -2.8  27.0   075   30   15   2.7   1.5   10.4  50.7     0.2      M    M
  9250   -2.7  27.1   070   29   15   2.4   1.3    9.8  49.7    -0.3    276  1.4
  9000   -2.5  27.5   065   29   15   2.2   1.2    9.3  48.7    -0.9    264  1.3
  8750   -2.3  27.9   060   28   15   3.7   2.1    8.7  47.7    -1.4    250  1.3
  8500   -2.0  28.4   055   27   14   4.6   2.5    8.3  47.0    -1.8    233  1.2
  8250   -1.6  29.1   050   27   14   5.0   2.8    7.9  46.2    -2.2    216  1.1
  8000   -1.2  29.8   045   26   13   6.5   3.5    7.6  45.7    -2.5    196  1.0
  7750   -0.8  30.6   040   25   13   5.7   3.1    7.3  45.2    -2.8    175  0.9
  7500   -0.4  31.3   035   24   12   4.9   2.7    7.0  44.6    -3.2    156  0.8
  7250   -0.0  32.0   035   23   12   5.8   3.2    6.6  43.9    -3.6    138  0.7
  7000    0.4  32.7   030   22   11   6.3   3.4    6.4  43.4    -3.9    117  0.6
  6750    0.9  33.6   025   21   11   6.0   3.3    6.1  43.0    -4.2     97  0.5
  6500    1.3  34.3   020   20   10   7.3   4.0    5.8  42.5    -4.4     76  0.4
  6250    1.9  35.4   015   17    9   8.6   4.7    5.7  42.3    -4.6     50  0.3
  6000    2.5  36.5   360   15    8   9.0   5.0    5.6  42.1    -4.7     24  0.1
  5750    3.2  37.8   345   14    7   7.6   4.2    5.6  42.0    -4.8      M    M
  5500    3.6  38.5   335   12    6   5.2   2.9    5.3  41.5    -5.1      M    M

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

           04/17/2015 at 0900 MDT          |       04/17/2015 at 1200 MDT
                                           |
K index... +13.8  LI... +271.5             | K index... +17.9  LI... +270.1
CAPE... +302.8  CIN... -0.2                | CAPE... +352.2  CIN... -1.6
                                           |
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 -56.8 -70.2  220  13  7   3.6   2.0 | -57.2 -71.0  215  18  9   3.7   2.0
 45000 -51.6 -60.9  200  17  9   1.3   0.7 | -51.7 -61.1  200  22 11   1.8   1.0
 40000 -49.5 -57.1  185  15  8   1.4   0.8 | -48.8 -55.8  170  16  8   1.9   1.0
 38000 -49.2 -56.6  160  18  9  -0.7  -0.4 | -47.9 -54.2  155  18  9   1.3   0.7
 36000 -49.6 -57.3  140  29 15  -0.7  -0.4 | -47.1 -52.8  140  22 11   1.3   0.7
 34000 -49.6 -57.3  125  42 21   4.9   2.7 | -46.1 -51.0  125  28 14   2.5   1.4
 32000 -46.8 -52.2  110  44 23   4.6   2.5 | -44.7 -48.5  105  34 17   2.4   1.3
 30000 -43.9 -47.0  100  47 24   6.2   3.4 | -43.1 -45.6  090  42 21   4.5   2.5
 29000 -42.1 -43.8  100  44 22   6.1   3.4 | -41.8 -43.2  090  42 22   4.3   2.4
 28000 -40.2 -40.4  100  40 21   6.1   3.4 | -40.5 -40.9  085  42 22   4.3   2.4
 27000 -38.4 -37.1  100  37 19   6.2   3.4 | -39.2 -38.6  085  43 22   4.0   2.2
 26000 -36.4 -33.5  100  35 18   6.8   3.7 | -37.4 -35.3  085  42 22   6.9   3.8
 25000 -34.3 -29.7  100  34 17   6.8   3.7 | -35.3 -31.5  085  41 21   6.9   3.8
 24000 -32.3 -26.1  100  32 17   6.6   3.6 | -33.2 -27.8  085  40 21   6.8   3.7
 23000 -29.9 -21.8  105  31 16   8.5   4.6 | -31.0 -23.8  085  39 20   7.8   4.3
 22000 -27.3 -17.1  110  29 15   8.5   4.6 | -28.7 -19.7  090  37 19   7.8   4.3
 21000 -24.8 -12.6  110  27 14   8.3   4.6 | -26.3 -15.3  090  36 19   7.6   4.2
 20000 -22.4  -8.3  115  26 13   8.1   4.5 | -24.3 -11.7  100  33 17   6.6   3.6
 19500 -21.2  -6.2  115  25 13   8.1   4.5 | -23.3  -9.9  100  31 16   6.6   3.6
 19000 -19.9  -3.8  120  24 13   8.1   4.5 | -22.3  -8.1  105  30 15   6.6   3.6
 18500 -18.7  -1.7  120  24 12   8.0   4.4 | -21.3  -6.3  110  28 15   6.6   3.6
 18000 -17.6   0.3  125  23 12   7.2   3.9 | -20.2  -4.4  110  27 14   8.0   4.4
 17500 -16.0   3.2  130  22 11   7.2   4.0 | -18.5  -1.3  110  26 13   7.9   4.3
 17000 -14.9   5.2  135  21 11   7.3   4.0 | -17.3   0.9  110  25 13   7.8   4.3
 16500 -13.8   7.2  135  21 11   7.4   4.1 | -16.1   3.0  110  24 12   7.8   4.3
 16000 -12.8   9.0  140  20 10   6.3   3.5 | -14.9   5.2  110  24 12   8.9   4.9
 15500 -11.9  10.6  135  17  9   6.5   3.6 | -13.6   7.5  110  24 13   8.9   4.9
 15000 -10.9  12.4  135  15  8   6.3   3.5 | -12.3   9.9  110  25 13   8.7   4.8
 14500 -10.1  13.8  130  14  7   6.4   3.5 | -11.0  12.2  115  27 14   8.6   4.7
 14000  -9.2  15.4  120  13  7   6.8   3.7 |  -9.7  14.5  115  29 15   8.0   4.4
 13500  -8.2  17.2  120  15  8   7.2   3.9 |  -8.7  16.3  120  30 15   7.2   3.9
 13000  -7.2  19.0  120  17  9   8.1   4.5 |  -7.7  18.1  125  31 16   7.1   3.9
 12500  -5.9  21.4  115  19 10   9.6   5.3 |  -6.7  19.9  125  30 15   7.0   3.9
 12000  -4.5  23.9  115  22 11   9.3   5.1 |  -5.8  21.6  130  29 15   7.7   4.2
 11500  -3.3  26.1  105  25 13   8.1   4.4 |  -4.5  23.9  130  27 14   9.5   5.2
 11000  -2.1  28.2  100  30 15   6.2   3.4 |  -3.2  26.2  130  26 13   8.8   4.8
 10500  -1.7  28.9  090  32 16   1.6   0.9 |  -2.2  28.0  125  24 13   6.7   3.7
 10250  -1.6  29.1  085  33 17   1.5   0.8 |  -1.7  28.9  120  24 12   7.0   3.9
 10000  -1.5  29.3  085  34 18   2.4   1.3 |  -1.2  29.8  115  23 12   6.0   3.3
  9750  -1.2  29.8  080  34 17   3.7   2.0 |  -0.9  30.4  105  23 12   3.5   1.9
  9500  -1.0  30.2  075  33 17   3.7   2.0 |  -0.6  30.9  100  24 12   2.8   1.5
  9250  -0.7  30.7  070  32 17   3.8   2.1 |  -0.4  31.3  090  24 13   2.8   1.5
  9000  -0.4  31.3  070  32 16   3.1   1.7 |  -0.2  31.6  085  26 13   4.0   2.2
  8750  -0.2  31.6  065  30 16   2.2   1.2 |   0.1  32.2  075  26 13   4.3   2.4
  8500  -0.1  31.8  060  29 15   2.3   1.3 |   0.4  32.7  070  27 14   3.4   1.8
  8250   0.1  32.2  050  27 14   2.2   1.2 |   0.6  33.1  065  28 14   4.0   2.2
  8000   0.3  32.5  045  26 14   2.5   1.4 |   1.0  33.8  060  29 15   5.5   3.0
  7750   0.4  32.7  035  25 13   1.0   0.5 |   1.4  34.5  055  28 15   5.8   3.2
  7500   0.4  32.7  025  25 13  -0.2  -0.1 |   1.8  35.2  050  28 14   5.7   3.1
  7250   0.4  32.7  020  25 13  -0.3  -0.2 |   2.2  36.0  045  28 14   5.1   2.8
  7000   0.4  32.7  010  25 13  -1.0  -0.6 |   2.6  36.7  040  26 14   5.0   2.7
  6750   0.3  32.5  360  25 13  -0.6  -0.3 |   2.9  37.2  035  25 13   3.3   1.8
  6500   0.3  32.5  350  26 13   1.3   0.7 |   3.0  37.4  025  24 13   2.1   1.1
  6250   0.5  32.9  340  25 13   3.7   2.0 |   3.3  37.9  020  23 12   3.7   2.0
  6000   0.8  33.4  335  23 12   4.1   2.3 |   3.5  38.3  015  20 10   4.1   2.2
  5750   1.1  34.0  330  21 11   5.0   2.7 |   3.8  38.8  005  18  9   3.6   2.0
  5500   1.7  35.1  325  18  9   9.5   5.2 |   4.1  39.4  360  15  8   5.2   2.8

           04/17/2015 at 1500 MDT          |       04/17/2015 at 1800 MDT
                                           |
K index... +14.3  LI... +269.6             | K index... +17.4  LI... +272.9
CAPE... +517.6  CIN... -1.1                | CAPE... +81.3  CIN... -8.8
                                           |
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 -56.7 -70.1  220  20 10   3.8   2.1 | -56.3 -69.3  225  18  9   3.7   2.0
 45000 -51.0 -59.8  205  23 12   2.1   1.1 | -50.9 -59.6  205  21 11   2.1   1.2
 40000 -47.9 -54.2  165  18  9   2.1   1.2 | -47.7 -53.9  180  18  9   2.1   1.2
 38000 -46.6 -51.9  150  18  9   2.2   1.2 | -46.2 -51.2  165  18  9   2.9   1.6
 36000 -45.3 -49.5  140  19 10   2.2   1.2 | -44.3 -47.7  145  18  9   2.9   1.6
 34000 -43.7 -46.7  125  20 10   3.6   2.0 | -42.6 -44.7  130  20 10   2.1   1.2
 32000 -41.7 -43.1  115  25 13   3.5   1.9 | -41.3 -42.3  115  20 10   2.2   1.2
 30000 -39.6 -39.3  105  31 16   2.8   1.5 | -40.0 -40.0  105  21 11   2.6   1.4
 29000 -38.8 -37.8  095  33 17   2.6   1.4 | -39.2 -38.6  095  22 11   2.7   1.5
 28000 -38.0 -36.4  085  36 18   2.6   1.4 | -38.4 -37.1  090  24 12   2.7   1.5
 27000 -37.3 -35.1  075  40 20   2.6   1.4 | -37.6 -35.7  080  26 13   2.7   1.5
 26000 -36.3 -33.3  075  41 21   3.4   1.9 | -36.8 -34.2  080  26 13   2.1   1.2
 25000 -35.3 -31.5  075  41 21   3.4   1.9 | -36.2 -33.2  085  25 13   2.1   1.2
 24000 -34.3 -29.7  075  41 21   3.5   1.9 | -35.6 -32.1  090  24 12   2.4   1.3
 23000 -32.8 -27.0  075  40 21   6.0   3.3 | -34.0 -29.2  095  23 12   8.2   4.5
 22000 -31.0 -23.8  080  38 20   6.1   3.4 | -31.5 -24.7  100  22 12   8.5   4.6
 21000 -29.2 -20.6  080  37 19   5.9   3.2 | -29.0 -20.2  110  22 11   8.6   4.7
 20000 -26.9 -16.4  085  36 19   7.9   4.3 | -26.6 -15.9  115  20 10   7.5   4.1
 19500 -25.8 -14.4  090  36 18   7.9   4.3 | -25.5 -13.9  115  19 10   7.6   4.1
 19000 -24.6 -12.3  090  36 18   7.9   4.3 | -24.4 -11.9  120  18  9   7.6   4.2
 18500 -23.4 -10.1  095  35 18   7.9   4.4 | -23.3  -9.9  120  18  9   7.6   4.2
 18000 -21.7  -7.1  095  36 18   7.3   4.0 | -21.6  -6.9  125  16  8   7.3   4.0
 17500 -20.6  -5.1  095  36 19   7.3   4.0 | -20.5  -4.9  125  15  8   7.4   4.0
 17000 -19.5  -3.1  095  36 19   7.3   4.0 | -19.5  -3.1  130  14  7   6.8   3.8
 16500 -18.4  -1.1  100  36 19   7.4   4.0 | -18.4  -1.1  130  13  7   6.9   3.8
 16000 -17.4   0.7  105  36 19   6.8   3.7 | -17.4   0.7  130  12  6   6.8   3.7
 15500 -16.4   2.5  110  35 18   6.6   3.6 | -16.4   2.5  135  11  6   6.8   3.7
 15000 -15.4   4.3  115  34 18   6.7   3.7 | -15.4   4.3  140  10  5   6.8   3.7
 14500 -14.4   6.1  120  30 16   6.9   3.8 | -14.4   6.1  145   9  5   6.8   3.7
 14000 -13.4   7.9  130  27 14   7.5   4.1 | -13.4   7.9  150   8  4   7.1   3.9
 13500 -12.2  10.0  130  24 12   8.9   4.9 | -12.2  10.0  155   8  4   8.0   4.4
 13000 -11.0  12.2  135  20 10   9.0   5.0 | -11.0  12.2  160   8  4   7.9   4.3
 12500  -9.7  14.5  135  18  9   9.3   5.1 |  -9.9  14.2  165   8  4   7.3   4.0
 12000  -8.3  17.1  135  17  9   9.4   5.1 |  -8.8  16.2  170   8  4   7.5   4.1
 11500  -6.9  19.6  135  16  8   9.7   5.3 |  -7.6  18.3  175   8  4   8.3   4.5
 11000  -5.5  22.1  130  16  8   9.5   5.2 |  -6.4  20.5  180   8  4   8.1   4.4
 10500  -4.3  24.3  125  15  8   8.5   4.7 |  -5.4  22.3  185   8  4   7.3   4.0
 10250  -3.7  25.3  125  15  8   7.3   4.0 |  -4.8  23.4  185   8  4   6.4   3.5
 10000  -3.1  26.4  125  15  8  12.3   6.7 |  -4.3  24.3  185   9  4  10.1   5.6
  9750  -2.0  28.4  115  15  8  12.8   7.0 |  -3.4  25.9  185   9  4  10.6   5.8
  9500  -1.4  29.5  110  15  8   7.9   4.3 |  -2.9  26.8  185   9  4   6.9   3.8
  9250  -0.7  30.7  105  15  8  10.0   5.5 |  -2.3  27.9  185   9  4   8.4   4.6
  9000  -0.1  31.8  100  15  8   6.5   3.6 |  -1.8  28.8  185   9  4   5.8   3.2
  8750   0.2  32.4  090  15  8   3.6   2.0 |  -1.5  29.3  185   8  4   2.5   1.4
  8500   0.5  32.9  075  16  8   4.9   2.7 |  -1.4  29.5  180   8  4   2.1   1.2
  8250   0.9  33.6  065  17  9   3.8   2.1 |  -1.3  29.7  175   8  4   2.8   1.5
  8000   1.0  33.8  055  18  9  -0.1  -0.1 |  -1.0  30.2  165   7  4   4.9   2.7
  7750   0.9  33.6  040  19 10  -1.7  -0.9 |  -0.6  30.9  150   6  3   6.4   3.5
  7500   0.8  33.4  030  20 10  -1.0  -0.6 |  -0.2  31.6  140   5  2   6.6   3.6
  7250   0.8  33.4  020  21 11  -0.7  -0.4 |   0.3  32.5  125   4  2   6.9   3.8
  7000   0.8  33.4  010  21 11  -0.5  -0.3 |   0.8  33.4  115   3  1   7.4   4.1
  6750   0.8  33.4  360  21 11   1.1   0.6 |   1.3  34.3  085   2  1   6.7   3.7
  6500   1.0  33.8  350  21 11   4.1   2.2 |   1.8  35.2  360   1  1   6.9   3.8
  6250   1.3  34.3  345  19 10   6.5   3.6 |   2.3  36.1  325   2  1   8.4   4.6
  6000   1.9  35.4  340  18  9   7.9   4.3 |   3.0  37.4  295   3  1   8.7   4.8
  5750   2.4  36.3  330  16  8   7.1   3.9 |   3.6  38.5  280   3  2   8.7   4.8
  5500   3.0  37.4  325  13  7   9.0   4.9 |   4.3  39.7  270   4  2  11.3   6.2
________________________________________________________________________________

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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