Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 151315
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0714 MDT Friday, March 15, 2024

This forecast is for Friday, March 15, 2024:

If the trigger temperature of 39.0 F/3.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9654 ft MSL (4344 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 C
Time of trigger temperature.................... 1300 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................. 7366 ft MSL (2056 ft AGL)
Thermal soaring outlook for Saturday 03/16..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 12676 ft MSL (7366 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 15868 ft MSL (10558 ft AGL)
Wave soaring outlook for Saturday 03/16........ Poor

Remarks...

Sunrise/Sunset.................... 07:09:31 / 19:06:46 MDT
Total possible sunshine........... 11 hr 57 min 15 sec (717 min 15 sec)
Altitude of sun at 13:08:08 MDT... 48.48 degrees

Upper air data from numerical model forecast valid on 03/15/2024 at 0600 MDT

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 8324 ft MSL (3014 ft AGL)
Lifted condensation level....... 9063 ft MSL (3753 ft AGL)
Lifted index.................... +8.7
K index......................... +10.1

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  -55.5 -67.9   255   19   10   1.8   1.0      M     M       M      M    M
 45000  -52.9 -63.2   255   22   11   1.9   1.0      M     M       M      M    M
 40000  -56.2 -69.2   225   27   14  -2.4  -1.3      M     M       M      M    M
 38000  -57.0 -70.6   225   29   15   0.9   0.5      M     M       M      M    M
 36000  -56.4 -69.5   240   30   15   0.9   0.5      M     M       M      M    M
 34000  -55.8 -68.4   250   32   16   2.5   1.4      M     M       M      M    M
 32000  -53.2 -63.8   240   41   21   4.4   2.4      M     M       M      M    M
 30000  -50.5 -58.9   230   50   26   7.4   4.1   25.7  78.3    15.9      M    M
 29000  -47.2 -53.0   235   48   25   8.7   4.8   25.1  77.1    15.6      M    M
 28000  -44.6 -48.3   235   46   24   8.7   4.8   24.7  76.4    15.5      M    M
 27000  -42.0 -43.6   235   44   23   8.8   4.8   24.4  75.9    15.5      M    M
 26000  -39.3 -38.7   235   44   23   9.1   5.0   24.0  75.2    15.4      M    M
 25000  -36.6 -33.9   240   44   22   9.1   5.0   23.7  74.7    15.3      M    M
 24000  -33.9 -29.0   240   43   22   9.0   5.0   23.6  74.5    15.4      M    M
 23000  -31.4 -24.5   240   43   22   8.6   4.7   23.1  73.6    15.2      M    M
 22000  -28.8 -19.8   235   43   22   8.6   4.7   22.7  72.8    15.0      M    M
 21000  -26.3 -15.3   235   43   22   7.9   4.3   22.4  72.3    14.9      M    M
 20000  -24.1 -11.4   230   37   19   7.4   4.0   21.4  70.6    14.2      M    M
 19500  -23.0  -9.4   225   35   18   7.4   4.0   21.0  69.8    13.9      M    M
 19000  -21.9  -7.4   220   32   17   7.3   4.0   20.6  69.1    13.7      M    M
 18500  -20.8  -5.4   220   30   16   6.8   3.7   20.2  68.4    13.4      M    M
 18000  -19.9  -3.8   215   27   14   5.8   3.2   19.6  67.2    12.9      M    M
 17500  -19.1  -2.4   215   23   12   5.8   3.2   18.9  66.0    12.4      M    M
 17000  -18.2  -0.8   210   20   10   5.6   3.1   18.2  64.8    11.8      M    M
 16500  -17.4   0.7   210   17    9   5.6   3.1   17.5  63.5    11.3      M    M
 16000  -16.5   2.3   205   14    7   6.2   3.4   16.8  62.3    10.7      M    M
 15500  -15.6   3.9   200   12    6   6.4   3.5   16.3  61.3    10.3      M    M
 15000  -14.2   6.4   185   11    6   5.8   3.2   15.4  59.7     9.6      M    M
 14500  -13.3   8.1   175   11    6   5.9   3.2   14.8  58.6     9.1      M    M
 14000  -12.5   9.5   170   11    6   4.0   2.2   14.0  57.2     8.5      M    M
 13500  -12.0  10.4   165   11    6   3.7   2.0   13.0  55.4     7.6      M    M
 13000  -11.5  11.3   165   11    6   2.9   1.6   12.0  53.6     6.7      M    M
 12500  -11.1  12.0   170   11    6   2.6   1.4   10.8  51.5     5.6      M    M
 12000  -10.7  12.7   175   11    6   3.5   1.9    9.7  49.5     4.6      M    M
 11500  -10.1  13.8   175   11    6   3.9   2.2    8.8  47.8     3.7      M    M
 11000   -9.6  14.7   180   11    6   3.3   1.8    7.8  46.1     2.8      M    M
 10500   -9.1  15.6   180   11    6   3.4   1.8    6.8  44.2     1.8      M    M
 10250   -8.9  16.0   180   11    5   2.4   1.3    6.3  43.3     1.3      M    M
 10000   -8.8  16.2   180   11    5   1.3   0.7    5.6  42.1     0.7      M    M
  9750   -8.7  16.3   180   10    5   3.5   1.9    5.0  41.0     0.1      M    M
  9500   -8.3  17.1   185   10    5   5.0   2.8    4.6  40.3    -0.3    292  1.5
  9250   -8.0  17.6   185   10    5   5.1   2.8    4.2  39.6    -0.7    274  1.4
  9000   -7.6  18.3   185   10    5   5.1   2.8    3.9  39.0    -1.0    255  1.3
  8750   -7.2  19.0   185   10    5   6.6   3.6    3.5  38.4    -1.3    236  1.2
  8500   -6.7  19.9   175   10    5   7.2   4.0    3.4  38.1    -1.5    212  1.1
  8250   -6.2  20.8   170   11    6   5.0   2.7    3.1  37.5    -1.8    192  1.0
  8000   -5.9  21.4   165   11    6   3.3   1.8    2.6  36.8    -2.3    175  0.9
  7750   -5.6  21.9   160   12    6   7.2   4.0    2.2  36.0    -2.7    158  0.8
  7500   -5.0  23.0   150   11    6   7.5   4.1    2.2  35.9    -2.8    132  0.7
  7250   -4.6  23.7   145   11    5   4.4   2.4    1.8  35.2    -3.1    114  0.6
  7000   -4.2  24.4   140   10    5   4.3   2.3    1.4  34.6    -3.5     96  0.5
  6750   -3.9  25.0   135   10    5   8.1   4.4    1.1  33.9    -3.9     77  0.4
  6500   -3.1  26.4   125    9    5   9.2   5.0    1.1  34.0    -3.9     48  0.2
  6250   -2.7  27.1   120    8    4   6.1   3.4    0.9  33.6    -4.2     26  0.1
  6000   -2.2  28.0   115    7    4   6.1   3.3    0.6  33.1    -4.4      5  0.0
  5750   -1.8  28.8   110    7    3   6.3   3.5    0.3  32.6    -4.7      M    M
  5500   -1.2  29.8   105    5    3  10.2   5.6    0.2  32.4    -4.9      M    M

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

           03/15/2024 at 0900 MDT          |       03/15/2024 at 1200 MDT
                                           |
CAPE...    +5.4    LI...       +6.7        | CAPE...    +4.6    LI...       +5.2
CINH...    -0.3    K Index... +10.2        | CINH...    -0.1    K Index...  +9.2
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -55.9 -68.6  250  19 10   1.3   0.7 | -56.7 -70.1  255  25 13   1.4   0.8
 45000 -53.8 -64.8  255  19 10   0.7   0.4 | -54.5 -66.1  250  24 13   0.6   0.3
 40000 -56.9 -70.4  230  24 12  -2.1  -1.2 | -57.5 -71.5  230  32 16  -2.1  -1.2
 38000 -57.4 -71.3  230  27 14   1.3   0.7 | -57.9 -72.2  225  34 17   1.9   1.0
 36000 -56.7 -70.1  235  29 15   1.3   0.7 | -56.8 -70.2  230  33 17   1.8   1.0
 34000 -55.9 -68.6  235  31 16   3.5   1.9 | -55.6 -68.1  230  33 17   4.1   2.3
 32000 -53.0 -63.4  235  37 19   4.9   2.7 | -52.5 -62.5  220  37 19   5.1   2.8
 30000 -49.2 -56.6  230  42 22   9.2   5.0 | -48.7 -55.7  210  40 21   8.9   4.9
 29000 -46.5 -51.7  230  42 22   9.0   5.0 | -46.0 -50.8  215  38 20   8.9   4.9
 28000 -43.7 -46.7  230  41 21   9.0   5.0 | -43.4 -46.1  220  37 19   8.9   4.9
 27000 -41.0 -41.8  225  41 21   8.9   4.9 | -40.7 -41.3  225  36 18   8.7   4.8
 26000 -38.4 -37.1  230  37 19   8.7   4.8 | -38.2 -36.8  230  33 17   8.6   4.7
 25000 -35.8 -32.4  235  34 18   8.7   4.8 | -35.6 -32.1  235  32 16   8.6   4.7
 24000 -33.2 -27.8  235  31 16   8.6   4.7 | -33.0 -27.4  240  30 15   8.5   4.7
 23000 -30.8 -23.4  240  31 16   8.0   4.4 | -30.6 -23.1  240  27 14   8.2   4.5
 22000 -28.4 -19.1  245  30 15   8.0   4.4 | -28.1 -18.6  245  25 13   8.2   4.5
 21000 -26.1 -15.0  245  30 15   7.9   4.4 | -25.7 -14.3  250  22 12   8.0   4.4
 20000 -23.7 -10.7  245  29 15   7.9   4.3 | -23.4 -10.1  255  21 11   7.9   4.3
 19500 -22.5  -8.5  250  28 15   7.9   4.3 | -22.2  -8.0  255  20 10   7.9   4.3
 19000 -21.4  -6.5  250  28 14   7.9   4.3 | -21.0  -5.8  255  20 10   7.9   4.3
 18500 -20.2  -4.4  250  27 14   7.5   4.1 | -19.8  -3.6  260  19 10   7.9   4.3
 18000 -19.1  -2.4  250  26 13   7.2   3.9 | -18.7  -1.7  260  18  9   7.8   4.3
 17500 -18.1  -0.6  250  24 13   7.1   3.9 | -17.5   0.5  265  18  9   7.8   4.3
 17000 -17.2   1.0  250  22 11   5.6   3.0 | -16.3   2.7  260  17  9   8.2   4.5
 16500 -16.3   2.7  245  19 10   5.7   3.1 | -15.1   4.8  260  16  8   8.2   4.5
 16000 -15.5   4.1  240  16  8   5.5   3.0 | -13.9   7.0  260  15  8   7.5   4.1
 15500 -14.7   5.5  230  14  7   5.5   3.0 | -12.3   9.9  250  13  6   7.5   4.1
 15000 -13.4   7.9  210  12  6   6.8   3.7 | -11.3  11.7  240  12  6   6.4   3.5
 14500 -12.4   9.7  200  13  7   6.8   3.7 | -10.3  13.5  230  11  6   6.6   3.6
 14000 -11.5  11.3  190  14  7   5.1   2.8 |  -9.4  15.1  220  11  6   5.2   2.8
 13500 -10.8  12.6  180  15  8   5.1   2.8 |  -8.7  16.3  215  12  6   5.2   2.9
 13000 -10.1  13.8  175  16  8   4.2   2.3 |  -8.0  17.6  205  13  7   3.6   2.0
 12500  -9.4  15.1  170  16  8   4.1   2.3 |  -7.5  18.5  200  15  8   3.2   1.8
 12000  -8.8  16.2  165  16  8   3.7   2.0 |  -7.1  19.2  195  17  9   2.8   1.5
 11500  -8.3  17.1  165  15  8   3.7   2.0 |  -6.7  19.9  185  18  9   2.7   1.5
 11000  -7.8  18.0  170  14  7   3.1   1.7 |  -6.3  20.7  180  19 10   3.1   1.7
 10500  -7.4  18.7  175  14  7   3.1   1.7 |  -5.8  21.6  180  18  9   3.5   1.9
 10250  -7.2  19.0  180  14  7   2.6   1.4 |  -5.6  21.9  180  18  9   2.0   1.1
 10000  -7.0  19.4  180  14  7   2.0   1.1 |  -5.5  22.1  180  18  9   1.9   1.1
  9750  -6.8  19.8  185  14  7   3.0   1.7 |  -5.2  22.6  180  18  9   5.4   3.0
  9500  -6.6  20.1  185  14  7   3.7   2.0 |  -4.7  23.5  185  18  9   7.4   4.1
  9250  -6.4  20.5  190  14  7   2.0   1.1 |  -4.2  24.4  190  18  9   4.6   2.5
  9000  -6.3  20.7  190  14  7   0.4   0.2 |  -4.0  24.8  190  18  9   2.2   1.2
  8750  -6.2  20.8  195  15  7   2.1   1.2 |  -3.8  25.2  190  18  9   4.3   2.3
  8500  -6.0  21.2  190  14  7   3.9   2.1 |  -3.4  25.9  195  18  9   4.9   2.7
  8250  -5.7  21.7  190  14  7   4.3   2.4 |  -3.1  26.4  195  18  9   3.6   2.0
  8000  -5.4  22.3  190  14  7   3.8   2.1 |  -2.9  26.8  190  17  9   2.9   1.6
  7750  -5.1  22.8  185  14  7   6.4   3.5 |  -2.7  27.1  190  17  9   4.1   2.2
  7500  -4.5  23.9  180  14  7   7.7   4.2 |  -2.4  27.7  185  16  8   5.6   3.1
  7250  -4.1  24.6  175  13  7   5.8   3.2 |  -2.0  28.4  180  16  8   6.0   3.3
  7000  -3.6  25.5  175  13  7   6.8   3.7 |  -1.5  29.3  180  15  8   5.2   2.8
  6750  -3.2  26.2  170  13  6   4.7   2.6 |  -1.1  30.0  175  15  8   8.3   4.6
  6500  -2.9  26.8  165  12  6   5.3   2.9 |  -0.4  31.3  170  14  7  10.0   5.5
  6250  -2.3  27.9  160  11  6   8.2   4.5 |   0.3  32.5  170  13  7   8.6   4.7
  6000  -1.8  28.8  155   9  5   6.2   3.4 |   0.9  33.6  165  12  6   7.5   4.1
  5750  -1.4  29.5  150   9  4   7.0   3.8 |   1.4  34.5  165  12  6   8.8   4.9
  5500  -0.7  30.7  150   7  4  11.7   6.4 |   2.3  36.1  165  10  5  16.5   9.1

           03/15/2024 at 1500 MDT          |       03/15/2024 at 1800 MDT
                                           |
CAPE...    +3.8    LI...       +2.9        | CAPE...    +1.2    LI...       +2.5
CINH...     0.0    K Index... +12.6        | CINH...    -0.0    K Index... +14.8
                                           |
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  260  27 14   1.3   0.7 | -57.1 -70.8  260  29 15   1.5   0.8
 45000 -54.7 -66.5  250  28 14   0.3   0.2 | -54.7 -66.5  255  30 15   0.5   0.3
 40000 -58.1 -72.6  240  35 18  -2.3  -1.3 | -58.1 -72.6  245  29 15  -2.4  -1.3
 38000 -58.3 -72.9  240  37 19   2.5   1.3 | -58.2 -72.8  240  29 15   2.9   1.6
 36000 -56.9 -70.4  235  38 20   2.4   1.3 | -56.5 -69.7  230  32 17   2.9   1.6
 34000 -55.3 -67.5  230  40 20   4.9   2.7 | -54.7 -66.5  225  35 18   4.6   2.5
 32000 -52.0 -61.6  215  39 20   5.6   3.1 | -51.6 -60.9  220  33 17   5.2   2.9
 30000 -47.9 -54.2  205  39 20   8.2   4.5 | -47.7 -53.9  215  30 15   8.2   4.5
 29000 -45.4 -49.7  205  36 19   8.2   4.5 | -45.3 -49.5  210  27 14   8.1   4.5
 28000 -43.0 -45.4  210  33 17   8.2   4.5 | -42.9 -45.2  210  25 13   8.1   4.5
 27000 -40.5 -40.9  210  29 15   8.5   4.7 | -40.4 -40.7  205  23 12   8.3   4.6
 26000 -37.9 -36.2  215  27 14   8.8   4.8 | -37.9 -36.2  205  20 10   8.6   4.7
 25000 -35.2 -31.4  215  25 13   8.8   4.8 | -35.3 -31.5  210  17  9   8.6   4.7
 24000 -32.6 -26.7  220  22 11   8.7   4.8 | -32.7 -26.9  215  14  7   8.6   4.7
 23000 -30.1 -22.2  225  19 10   8.4   4.6 | -30.2 -22.4  210  10  5   8.4   4.6
 22000 -27.6 -17.7  235  16  8   8.4   4.6 | -27.7 -17.9  205   7  3   8.4   4.6
 21000 -25.2 -13.4  245  13  7   7.8   4.3 | -25.2 -13.4  190   3  2   8.2   4.5
 20000 -22.9  -9.2  255  11  6   7.7   4.2 | -22.8  -9.0  160   2  1   8.1   4.4
 19500 -21.7  -7.1  260  10  5   7.7   4.2 | -21.6  -6.9  130   2  1   8.1   4.4
 19000 -20.6  -5.1  265   9  5   7.7   4.2 | -20.4  -4.7  100   2  1   8.1   4.4
 18500 -19.5  -3.1  275   8  4   7.8   4.3 | -19.2  -2.6  085   3  1   8.1   4.4
 18000 -18.3  -0.9  280   8  4   7.8   4.3 | -18.0  -0.4  085   3  1   8.1   4.4
 17500 -17.1   1.2  285   8  4   7.8   4.3 | -16.8   1.8  080   3  1   8.1   4.4
 17000 -15.9   3.4  285   8  4   8.1   4.5 | -15.6   3.9  080   3  1   8.1   4.4
 16500 -14.7   5.5  280   7  4   8.1   4.5 | -13.8   7.2  085   2  1   8.0   4.4
 16000 -13.5   7.7  275   7  4   7.8   4.3 | -12.6   9.3  115   2  1   7.7   4.2
 15500 -11.8  10.8  260   7  4   7.8   4.3 | -11.5  11.3  160   2  1   7.8   4.3
 15000 -10.7  12.7  250   8  4   7.9   4.3 | -10.4  13.3  195   3  1   7.2   4.0
 14500  -9.5  14.9  240   9  4   7.9   4.4 |  -9.3  15.3  210   5  2   7.3   4.0
 14000  -8.4  16.9  230  10  5   7.3   4.0 |  -8.3  17.1  215   6  3   6.8   3.7
 13500  -7.3  18.9  225  12  6   7.3   4.0 |  -7.3  18.9  215   9  4   6.7   3.7
 13000  -6.3  20.7  220  14  7   5.9   3.3 |  -6.3  20.7  215  10  5   6.3   3.4
 12500  -5.5  22.1  215  14  7   5.7   3.1 |  -5.4  22.3  215  12  6   6.1   3.4
 12000  -4.7  23.5  215  15  8   3.9   2.1 |  -4.5  23.9  220  13  7   5.6   3.1
 11500  -4.3  24.3  210  15  8   3.3   1.8 |  -3.8  25.2  220  13  7   5.3   2.9
 11000  -3.8  25.2  205  16  8   2.1   1.2 |  -3.0  26.6  220  14  7   4.2   2.3
 10500  -3.6  25.5  200  16  8   2.0   1.1 |  -2.5  27.5  220  13  7   3.7   2.0
 10250  -3.5  25.7  200  16  8   0.7   0.4 |  -2.3  27.9  225  13  7   3.0   1.7
 10000  -3.4  25.9  200  16  8   1.1   0.6 |  -2.1  28.2  220  13  7   1.7   0.9
  9750  -3.2  26.2  195  16  8   3.8   2.1 |  -2.0  28.4  220  13  6   1.7   0.9
  9500  -2.9  26.8  195  15  8   4.5   2.5 |  -1.9  28.6  220  11  6   2.2   1.2
  9250  -2.6  27.3  190  15  8   3.8   2.1 |  -1.8  28.8  220  10  5   1.8   1.0
  9000  -2.4  27.7  195  14  7   3.4   1.9 |  -1.7  28.9  220   9  5   1.4   0.8
  8750  -2.1  28.2  195  14  7   4.4   2.4 |  -1.6  29.1  220   9  4   1.8   1.0
  8500  -1.8  28.8  195  13  7   5.0   2.7 |  -1.4  29.5  220   7  4   2.1   1.1
  8250  -1.4  29.5  195  12  6   4.0   2.2 |  -1.3  29.7  225   6  3   2.3   1.3
  8000  -1.2  29.8  190  12  6   3.6   2.0 |  -1.1  30.0  220   5  2   2.3   1.3
  7750  -0.9  30.4  185  11  6   3.1   1.7 |  -0.9  30.4  215   4  2   3.7   2.0
  7500  -0.7  30.7  175  10  5   4.4   2.4 |  -0.6  30.9  225   3  2   4.7   2.6
  7250  -0.3  31.5  175  10  5   6.8   3.7 |  -0.3  31.5  230   3  1   4.2   2.3
  7000   0.2  32.4  175  10  5   6.8   3.7 |  -0.0  32.0  230   2  1   3.2   1.7
  6750   0.7  33.3  170  10  5   7.0   3.8 |   0.3  32.5  235   2  1   6.7   3.7
  6500   1.2  34.2  165  10  5   8.3   4.5 |   0.9  33.6  205   2  1   8.7   4.7
  6250   1.9  35.4  165   9  5   9.3   5.1 |   1.4  34.5  245   1  1   6.7   3.7
  6000   2.5  36.5  165   8  4   8.1   4.4 |   2.0  35.6  290   2  1   7.1   3.9
  5750   3.1  37.6  160   9  5   9.8   5.4 |   2.5  36.5  310   2  1   7.7   4.2
  5500   4.1  39.4  160   8  4  15.8   8.7 |   3.1  37.6  285   1  1   8.7   4.8
________________________________________________________________________________

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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