Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 151313
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0613 MST Thursday, February 15, 2018

This forecast is for Thursday, February 15, 2018:

If the trigger temperature of 52.5 F/11.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 9 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6548 ft MSL (1252 ft AGL)

Forecast maximum temperature................... 49.0 F/9.9 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1400 MST
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5719 ft MSL (424 ft AGL)
Thermal soaring outlook for Friday 02/16....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Decreasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 14406 ft MSL (9110 ft AGL)
Wave soaring outlook for Friday 02/16.......... Fair

Remarks...

Sunrise/Sunset.................... 06:51:36 / 17:35:36 MST
Total possible sunshine........... 10 hr 44 min 0 sec (644 min 0 sec)
Altitude of sun at 12:13:36 MST... 37.64 degrees

Upper air data from numerical model forecast valid on 02/15/2018 at 0500 MST

Freezing level.................. 9058 ft MSL (3762 ft AGL)
Convective condensation level... 13564 ft MSL (8268 ft AGL)
Lifted condensation level....... 11722 ft MSL (6426 ft AGL)
Lifted index.................... +9.4
K index......................... +8.4

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  -64.1 -83.4   245   48   25   4.1   2.2      M     M       M      M    M
 45000  -57.7 -71.9   245   50   26   3.0   1.6      M     M       M      M    M
 40000  -58.0 -72.4   250   67   34  -0.3  -0.1      M     M       M      M    M
 38000  -56.5 -69.7   250   72   37   6.3   3.4      M     M       M      M    M
 36000  -52.8 -63.0   250   74   38   6.3   3.4      M     M       M      M    M
 34000  -49.0 -56.2   250   76   39   7.2   3.9      M     M       M      M    M
 32000  -43.9 -47.0   245   71   36   7.6   4.1      M     M       M      M    M
 30000  -39.4 -38.9   240   67   34   6.1   3.3   38.2 100.8    21.6      M    M
 29000  -37.6 -35.7   240   65   33   6.3   3.4   36.7  98.0    20.7      M    M
 28000  -35.7 -32.3   245   62   32   6.3   3.4   35.3  95.6    19.9      M    M
 27000  -33.8 -28.8   245   60   31   6.4   3.5   34.1  93.4    19.2      M    M
 26000  -32.2 -26.0   245   56   29   5.0   2.8   32.4  90.3    18.1      M    M
 25000  -30.6 -23.1   245   50   26   5.1   2.8   30.6  87.0    16.9      M    M
 24000  -29.1 -20.4   250   45   23   5.1   2.8   28.9  84.0    15.7      M    M
 23000  -27.6 -17.7   250   40   20   5.2   2.8   27.2  80.9    14.5      M    M
 22000  -26.1 -15.0   255   35   18   5.2   2.8   25.5  77.8    13.3      M    M
 21000  -24.5 -12.1   255   30   16   5.4   3.0   23.9  75.0    12.1      M    M
 20000  -23.5 -10.3   260   26   13   2.7   1.5   21.6  70.8    10.3      M    M
 19500  -23.1  -9.6   260   23   12   2.7   1.5   20.3  68.6     9.2      M    M
 19000  -22.7  -8.9   260   21   11   2.7   1.5   19.1  66.4     8.2      M    M
 18500  -22.3  -8.1   260   18   10   2.5   1.4   17.9  64.2     7.2      M    M
 18000  -21.7  -7.1   260   16    8   7.0   3.8   17.0  62.6     6.4      M    M
 17500  -20.6  -5.1   265   15    8   7.5   4.1   16.6  61.9     6.1      M    M
 17000  -19.5  -3.1   265   14    7   7.6   4.2   16.2  61.2     5.8      M    M
 16500  -18.3  -0.9   260   14    7   7.7   4.2   15.9  60.6     5.5      M    M
 16000  -16.6   2.1   255   13    7   8.5   4.6   15.4  59.7     5.1      M    M
 15500  -15.3   4.5   255   13    7   8.9   4.9   15.2  59.4     5.0      M    M
 15000  -13.9   7.0   255   13    7   8.8   4.8   15.1  59.2     4.9      M    M
 14500  -12.7   9.1   260   14    7   8.4   4.6   14.9  58.8     4.7      M    M
 14000  -11.4  11.5   260   15    8   8.4   4.6   14.7  58.4     4.5      M    M
 13500  -10.2  13.6   265   17    8   8.6   4.7   14.5  58.0     4.3      M    M
 13000   -8.9  16.0   270   18    9   8.6   4.7   14.3  57.7     4.2      M    M
 12500   -7.8  18.0   275   19   10   6.9   3.8   13.9  57.1     3.9      M    M
 12000   -6.7  19.9   275   19   10   7.0   3.9   13.5  56.3     3.5      M    M
 11500   -5.6  21.9   275   19   10   7.8   4.3   13.1  55.6     3.1      M    M
 11000   -4.5  23.9   275   18    9   7.7   4.2   12.8  55.0     2.8      M    M
 10500   -3.4  25.9   275   18    9   7.4   4.1   12.4  54.4     2.5      M    M
 10250   -2.8  27.0   275   18    9   7.3   4.0   12.2  54.0     2.3      M    M
 10000   -2.2  28.0   275   18    9   9.5   5.2   12.1  53.8     2.2      M    M
  9750   -1.5  29.3   275   17    9   9.1   5.0   12.1  53.9     2.2      M    M
  9500   -0.9  30.4   275   17    9   7.0   3.8   12.0  53.5     2.0      M    M
  9250   -0.4  31.3   275   17    9   7.6   4.2   11.8  53.2     1.8      M    M
  9000    0.2  32.4   280   17    9   7.2   4.0   11.6  52.9     1.7      M    M
  8750    0.7  33.3   275   15    8   7.4   4.0   11.4  52.5     1.4      M    M
  8500    1.2  34.2   280   15    8   7.9   4.3   11.2  52.2     1.3      M    M
  8250    1.8  35.2   280   14    7   7.1   3.9   11.1  51.9     1.1      M    M
  8000    2.4  36.3   280   13    7   9.7   5.3   10.9  51.7     1.0      M    M
  7750    3.1  37.6   280   12    6   9.3   5.1   11.0  51.8     1.0      M    M
  7500    3.7  38.7   280   11    6   6.4   3.5   10.8  51.4     0.8      M    M
  7250    4.2  39.6   285   10    5   7.3   4.0   10.6  51.0     0.6      M    M
  7000    4.7  40.5   285    9    5   8.1   4.4   10.4  50.7     0.4      M    M
  6750    5.3  41.5   285    9    4   6.6   3.6   10.3  50.5     0.3      M    M
  6500    5.7  42.3   285    8    4   6.9   3.8   10.0  49.9    -0.0      8  0.0
  6250    6.2  43.2   280    7    4   1.0   0.5    9.7  49.4    -0.3      M    M
  6000    5.9  42.6   275    6    3  -4.1  -2.3    8.7  47.6    -1.4      M    M
  5750    5.5  41.9   265    6    3  -7.7  -4.2    7.6  45.7    -2.4      M    M
  5500    4.2  39.6   250    4    2 -27.7 -15.2    5.6  42.1    -4.5     23  0.1

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

           02/15/2018 at 0800 MST          |       02/15/2018 at 1100 MST
                                           |
CAPE...     0.0    LI...       +3.1        | CAPE...     0.0    LI...       +5.2
CINH...     0.0    K Index...  +8.9        | CINH...     0.0    K Index...  +4.4
                                           |
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 -64.3 -83.7  245  48 25   4.3   2.3 | -63.5 -82.3  250  49 25   4.5   2.4
 45000 -57.6 -71.7  240  51 26   3.2   1.8 | -56.5 -69.7  245  53 27   3.4   1.9
 40000 -57.8 -72.0  250  68 35  -0.2  -0.1 | -56.4 -69.5  250  66 34  -0.0  -0.0
 38000 -56.5 -69.7  250  73 38   5.6   3.1 | -55.3 -67.5  250  71 37   4.9   2.7
 36000 -53.2 -63.8  245  74 38   5.6   3.1 | -52.4 -62.3  245  75 38   4.8   2.7
 34000 -49.8 -57.6  245  76 39   6.9   3.8 | -49.4 -56.9  245  78 40   6.3   3.5
 32000 -45.3 -49.5  245  72 37   7.4   4.1 | -45.0 -49.0  245  75 39   7.3   4.0
 30000 -40.4 -40.7  240  68 35   6.5   3.6 | -40.1 -40.2  240  71 37   6.7   3.7
 29000 -38.4 -37.1  245  66 34   6.7   3.7 | -38.2 -36.8  240  69 35   6.5   3.6
 28000 -36.4 -33.5  245  63 32   6.7   3.7 | -36.2 -33.2  245  66 34   6.5   3.6
 27000 -34.3 -29.7  245  60 31   6.9   3.8 | -34.2 -29.6  245  64 33   6.6   3.6
 26000 -32.8 -27.0  245  56 29   4.6   2.5 | -32.4 -26.3  245  61 31   5.7   3.1
 25000 -31.4 -24.5  245  51 26   4.6   2.5 | -30.7 -23.3  245  58 30   5.7   3.1
 24000 -30.0 -22.0  250  46 24   4.6   2.5 | -29.0 -20.2  250  54 28   5.7   3.1
 23000 -28.4 -19.1  250  41 21   6.0   3.3 | -27.6 -17.7  250  49 25   3.5   1.9
 22000 -26.6 -15.9  250  36 19   6.0   3.3 | -26.6 -15.9  250  43 22   3.5   1.9
 21000 -24.8 -12.6  250  32 16   6.2   3.4 | -25.5 -13.9  250  37 19   3.2   1.7
 20000 -23.5 -10.3  255  28 14   4.0   2.2 | -23.9 -11.0  250  31 16   6.3   3.4
 19500 -22.9  -9.2  255  27 14   4.0   2.2 | -23.0  -9.4  250  28 14   6.3   3.4
 19000 -22.3  -8.1  255  25 13   4.0   2.2 | -22.0  -7.6  245  25 13   6.3   3.5
 18500 -21.7  -7.1  255  24 12   4.1   2.2 | -21.1  -6.0  245  22 11   6.5   3.6
 18000 -21.1  -6.0  255  22 11   4.0   2.2 | -20.3  -4.5  245  20 10   3.0   1.6
 17500 -20.5  -4.9  255  19 10   4.1   2.3 | -20.0  -4.0  250  21 11   2.4   1.3
 17000 -19.5  -3.1  250  15  8   7.2   3.9 | -19.7  -3.5  255  22 11   3.0   1.6
 16500 -18.4  -1.1  245  14  7   7.2   4.0 | -19.1  -2.4  255  21 11   4.3   2.4
 16000 -17.3   0.9  245  13  7   8.1   4.4 | -18.5  -1.3  255  21 11   4.2   2.3
 15500 -16.0   3.2  250  14  7   8.6   4.7 | -17.7   0.1  255  20 10   6.1   3.3
 15000 -14.7   5.5  255  16  8   8.1   4.4 | -16.4   2.5  260  21 11   5.8   3.2
 14500 -13.7   7.3  265  18  9   6.7   3.6 | -15.6   3.9  265  19 10   5.5   3.0
 14000 -12.7   9.1  270  20 10   6.7   3.7 | -14.8   5.4  270  18  9   5.8   3.2
 13500 -11.7  10.9  270  20 10   6.3   3.5 | -13.7   7.3  270  16  8   8.4   4.6
 13000 -10.8  12.6  275  20 10   6.3   3.5 | -12.5   9.5  275  15  8   8.2   4.5
 12500  -9.8  14.4  275  19 10   7.5   4.1 | -11.3  11.7  275  14  7   8.5   4.7
 12000  -8.7  16.3  275  17  9   7.4   4.1 | -10.0  14.0  280  13  7   8.5   4.7
 11500  -7.5  18.5  275  15  8   8.4   4.6 |  -8.7  16.3  280  13  6   8.8   4.8
 11000  -6.3  20.7  275  15  8   8.3   4.6 |  -7.4  18.7  280  13  7   8.7   4.8
 10500  -5.3  22.5  270  14  7   6.8   3.7 |  -6.3  20.7  280  12  6   7.1   3.9
 10250  -4.8  23.4  270  13  7   6.5   3.6 |  -5.8  21.6  280  12  6   6.5   3.6
 10000  -4.3  24.3  270  12  6   8.3   4.5 |  -5.3  22.5  280  12  6   9.1   5.0
  9750  -3.6  25.5  270  12  6   7.4   4.1 |  -4.5  23.9  280  11  6   8.7   4.8
  9500  -3.2  26.2  270  11  6   4.9   2.7 |  -4.0  24.8  275  10  5   5.8   3.2
  9250  -2.8  27.0  270   9  5   5.8   3.2 |  -3.6  25.5  275   9  5   6.7   3.7
  9000  -2.4  27.7  275   8  4   4.8   2.7 |  -3.1  26.4  270   8  4   6.1   3.3
  8750  -2.1  28.2  270   6  3   4.6   2.5 |  -2.7  27.1  260   7  3   6.1   3.3
  8500  -1.7  28.9  275   5  2   5.2   2.8 |  -2.2  28.0  250   6  3   6.5   3.5
  8250  -1.4  29.5  275   3  2   4.9   2.7 |  -1.7  28.9  245   6  3   6.3   3.5
  8000  -1.0  30.2  285   2  1   5.5   3.0 |  -1.3  29.7  230   5  3   4.9   2.7
  7750  -0.6  30.9  005   1  0   4.1   2.2 |  -1.0  30.2  210   5  2   4.1   2.2
  7500  -0.4  31.3  045   2  1   2.5   1.4 |  -0.7  30.7  200   4  2   3.9   2.1
  7250  -0.1  31.8  055   3  1   3.3   1.8 |  -0.3  31.5  185   4  2   5.6   3.1
  7000   0.2  32.4  050   4  2   4.9   2.7 |   0.2  32.4  170   3  2   7.8   4.3
  6750   0.5  32.9  040   5  3   3.5   1.9 |   0.8  33.4  155   3  1   8.8   4.8
  6500   0.7  33.3  035   6  3   1.5   0.8 |   1.5  34.7  150   2  1   9.8   5.4
  6250   0.8  33.4  035   7  3   3.2   1.8 |   2.2  36.0  150   2  1  10.1   5.5
  6000   1.1  34.0  045   6  3   4.2   2.3 |   3.0  37.4  145   2  1  10.5   5.8
  5750   1.4  34.5  055   6  3   3.8   2.1 |   3.8  38.8  145   2  1  10.0   5.5
  5500   1.5  34.7  070   5  2   1.6   0.9 |   4.6  40.3  145   2  1  14.3   7.8

           02/15/2018 at 1400 MST          |       02/15/2018 at 1700 MST
                                           |
CAPE...     0.0    LI...       +2.1        | CAPE...    +5.0    LI...       +1.2
CINH...     0.0    K Index... +11.8        | CINH...   -22.6    K Index...  +9.6
                                           |
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 -62.9 -81.2  250  51 26   4.1   2.3 | -63.5 -82.3  255  54 28   3.3   1.8
 45000 -56.7 -70.1  245  54 28   4.3   2.3 | -58.5 -73.3  250  60 31   3.5   1.9
 40000 -56.9 -70.4  245  69 36  -0.5  -0.3 | -56.7 -70.1  250  69 36   1.0   0.6
 38000 -55.9 -68.6  245  74 38   5.3   2.9 | -55.4 -67.7  250  73 37   4.6   2.5
 36000 -52.8 -63.0  245  75 39   5.2   2.9 | -52.3 -62.1  250  75 38   4.7   2.6
 34000 -49.6 -57.3  240  77 39   5.8   3.2 | -49.4 -56.9  250  76 39   5.7   3.1
 32000 -45.8 -50.4  245  73 38   6.4   3.5 | -45.8 -50.4  250  72 37   6.1   3.3
 30000 -41.9 -43.4  245  70 36   6.6   3.6 | -42.1 -43.8  250  69 35   6.0   3.3
 29000 -39.4 -38.9  245  68 35   6.7   3.7 | -40.3 -40.5  250  66 34   6.0   3.3
 28000 -37.4 -35.3  245  66 34   6.7   3.7 | -38.5 -37.3  250  63 32   6.0   3.3
 27000 -35.5 -31.9  250  64 33   6.8   3.7 | -36.7 -34.1  250  59 31   6.0   3.3
 26000 -33.8 -28.8  250  61 32   5.1   2.8 | -34.9 -30.8  250  57 29   6.3   3.5
 25000 -32.2 -26.0  250  58 30   5.1   2.8 | -33.2 -27.8  255  54 28   6.4   3.5
 24000 -30.7 -23.3  250  55 28   5.1   2.8 | -31.0 -23.8  255  51 26   6.3   3.4
 23000 -29.5 -21.1  250  51 26   3.0   1.6 | -29.6 -21.3  255  48 25   2.3   1.3
 22000 -28.6 -19.5  255  47 24   2.9   1.6 | -28.9 -20.0  255  44 23   2.4   1.3
 21000 -27.7 -17.9  255  43 22   2.8   1.5 | -28.2 -18.8  255  40 21   2.4   1.3
 20000 -26.6 -15.9  255  38 20   4.3   2.4 | -27.5 -17.5  255  36 19   2.5   1.4
 19500 -26.0 -14.8  255  36 18   4.4   2.4 | -26.9 -16.4  250  32 17   2.5   1.4
 19000 -25.3 -13.5  255  34 17   4.4   2.4 | -26.5 -15.7  250  30 15   2.6   1.4
 18500 -24.7 -12.5  250  31 16   4.4   2.4 | -26.2 -15.2  250  28 14   2.9   1.6
 18000 -24.0 -11.2  250  29 15   4.4   2.4 | -25.6 -14.1  250  25 13   4.7   2.6
 17500 -23.4 -10.1  250  26 13   4.5   2.5 | -24.9 -12.8  245  23 12   4.3   2.3
 17000 -22.8  -9.0  250  23 12   5.7   3.1 | -24.0 -11.2  240  21 11   9.2   5.0
 16500 -21.7  -7.1  250  21 11   7.7   4.2 | -22.6  -8.7  245  20 10   9.4   5.2
 16000 -20.5  -4.9  250  20 10   7.7   4.2 | -21.2  -6.2  245  19 10   8.0   4.4
 15500 -18.9  -2.0  255  19 10   7.2   3.9 | -20.2  -4.4  250  18  9   7.1   3.9
 15000 -17.9  -0.2  260  19 10   7.6   4.2 | -19.1  -2.4  255  18  9   6.9   3.8
 14500 -16.7   1.9  260  18  9   8.4   4.6 | -18.2  -0.8  260  16  8   6.5   3.6
 14000 -15.4   4.3  260  16  8   8.3   4.5 | -17.2   1.0  260  15  8   6.9   3.8
 13500 -14.3   6.3  260  14  7   7.6   4.2 | -16.0   3.2  260  14  7   8.5   4.7
 13000 -13.1   8.4  265  13  7   7.7   4.2 | -14.8   5.4  265  13  7   8.4   4.6
 12500 -12.0  10.4  270  12  6   8.2   4.5 | -13.5   7.7  265  12  6   8.4   4.6
 12000 -10.8  12.6  270  11  5   8.0   4.4 | -12.3   9.9  270  11  5   8.5   4.7
 11500  -9.6  14.7  280  11  5   7.1   3.9 | -11.0  12.2  270  10  5   9.3   5.1
 11000  -8.6  16.5  285  11  6   7.1   3.9 |  -9.6  14.7  275   9  4   9.2   5.0
 10500  -7.5  18.5  290  10  5   7.2   3.9 |  -8.2  17.2  280   8  4   8.8   4.8
 10250  -7.0  19.4  295   9  5   6.4   3.5 |  -7.5  18.5  285   8  4   9.8   5.4
 10000  -6.5  20.3  295   8  4   9.3   5.1 |  -6.9  19.6  290   8  4   6.1   3.4
  9750  -5.7  21.7  300   8  4   9.7   5.3 |  -6.5  20.3  290   8  4   6.7   3.7
  9500  -5.1  22.8  305   7  4   7.2   4.0 |  -5.8  21.6  295   8  4  10.7   5.9
  9250  -4.6  23.7  310   6  3   7.7   4.2 |  -5.0  23.0  295   8  4   9.7   5.3
  9000  -4.0  24.8  315   6  3   8.5   4.7 |  -4.3  24.3  300   8  4   9.6   5.3
  8750  -3.3  26.1  320   5  3   9.1   5.0 |  -3.6  25.5  300   9  4   9.3   5.1
  8500  -2.7  27.1  320   5  3   8.5   4.6 |  -2.9  26.8  305   9  4   9.4   5.1
  8250  -2.0  28.4  325   5  3   9.2   5.0 |  -2.2  28.0  305   9  4   9.5   5.2
  8000  -1.3  29.7  330   5  2  11.1   6.1 |  -1.5  29.3  310   9  4  10.1   5.5
  7750  -0.5  31.1  330   5  2   9.9   5.4 |  -0.7  30.7  315   9  4   8.9   4.9
  7500   0.2  32.4  330   5  2   7.8   4.3 |  -0.1  31.8  315   9  4   7.7   4.3
  7250   0.8  33.4  335   5  2   9.4   5.2 |   0.5  32.9  320   9  4   9.2   5.0
  7000   1.6  34.9  335   5  2  10.9   6.0 |   1.2  34.2  320   9  4  10.4   5.7
  6750   2.3  36.1  335   5  2   9.5   5.2 |   2.0  35.6  325   9  4   9.2   5.0
  6500   3.0  37.4  335   5  2   9.2   5.0 |   2.6  36.7  325   9  4   8.8   4.8
  6250   3.8  38.8  335   5  2  10.7   5.9 |   3.3  37.9  325   8  4   9.5   5.2
  6000   4.6  40.3  335   5  2  11.4   6.3 |   4.0  39.2  330   8  4   9.9   5.4
  5750   5.4  41.7  335   4  2  10.1   5.6 |   4.7  40.5  330   7  4   8.3   4.6
  5500   6.1  43.0  335   4  2   8.6   4.7 |   5.2  41.4  335   6  3   3.7   2.1
________________________________________________________________________________

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.

CINH (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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