Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 121322
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0721 MDT Tuesday, March 12, 2024

This forecast is for Tuesday, March 12, 2024:

If the trigger temperature of 51.6 F/10.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1144 ft/min (5.8 m/s)
   Maximum height of thermals.................. 18990 ft MSL (13659 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1400 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 15611 ft MSL (10280 ft AGL)
Thermal soaring outlook for Wednesday 03/13.... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Becoming fair
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14434 ft MSL (9103 ft AGL)
Wave soaring outlook for Wednesday 03/13....... Poor

Remarks...

Sunrise/Sunset.................... 07:14:18 / 19:03:40 MDT
Total possible sunshine........... 11 hr 49 min 22 sec (709 min 22 sec)
Altitude of sun at 13:08:59 MDT... 47.28 degrees

Upper air data from numerical model forecast valid on 03/12/2024 at 0600 MDT

Freezing level.................. 8920 ft MSL (3589 ft AGL)
Convective condensation level... 14063 ft MSL (8732 ft AGL)
Lifted condensation level....... 15831 ft MSL (10500 ft AGL)
Lifted index.................... +1.3
K index......................... +9.0

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  -56.6 -69.9   265   26   13   1.8   1.0      M     M       M      M    M
 45000  -53.7 -64.7   275   33   17   2.0   1.1      M     M       M      M    M
 40000  -56.0 -68.8   290   35   18  -1.8  -1.0      M     M       M      M    M
 38000  -56.7 -70.1   300   37   19   0.4   0.2      M     M       M      M    M
 36000  -56.4 -69.5   320   43   22   0.5   0.3      M     M       M      M    M
 34000  -56.1 -69.0   335   54   28   1.2   0.7      M     M       M      M    M
 32000  -51.2 -60.2   340   58   30   7.7   4.2      M     M       M      M    M
 30000  -46.6 -51.9   340   60   31   8.2   4.5   29.4  84.9     8.7      M    M
 29000  -44.1 -47.4   340   59   30   8.2   4.5   28.6  83.5     8.2      M    M
 28000  -41.6 -42.9   340   57   30   8.2   4.5   28.0  82.4     7.9      M    M
 27000  -39.2 -38.6   335   56   29   8.3   4.5   27.5  81.6     7.6      M    M
 26000  -36.9 -34.4   335   55   28   7.5   4.1   26.7  80.1     7.0      M    M
 25000  -34.6 -30.3   330   53   27   7.5   4.1   25.8  78.5     6.4      M    M
 24000  -32.4 -26.3   325   51   27   7.6   4.1   25.1  77.1     5.9      M    M
 23000  -30.3 -22.5   320   48   25   6.4   3.5   24.0  75.2     5.1      M    M
 22000  -28.4 -19.1   320   42   22   6.4   3.5   22.8  73.0     4.1      M    M
 21000  -26.4 -15.5   310   37   19   6.6   3.6   21.7  71.0     3.2      M    M
 20000  -25.0 -13.0   305   30   16   4.5   2.5   19.9  67.8     1.8      M    M
 19500  -24.3 -11.7   305   27   14   4.5   2.5   18.9  66.1     1.0      M    M
 19000  -23.6 -10.5   300   23   12   4.5   2.5   18.0  64.5     0.2      M    M
 18500  -23.0  -9.4   295   20   10   4.3   2.4   17.2  62.9    -0.6   1217  6.2
 18000  -21.6  -6.9   290   17    9   7.2   3.9   16.3  61.3    -1.4   1154  5.9
 17500  -20.5  -4.9   295   16    8   7.2   3.9   15.8  60.5    -1.8   1107  5.6
 17000  -19.4  -2.9   300   16    8   7.7   4.2   15.5  59.8    -2.2   1060  5.4
 16500  -18.3  -0.9   300   17    9   7.7   4.2   15.1  59.2    -2.5   1011  5.1
 16000  -17.1   1.2   305   18    9   8.0   4.4   14.8  58.6    -2.8    961  4.9
 15500  -15.9   3.4   305   19   10   8.0   4.4   14.5  58.1    -3.1    911  4.6
 15000  -14.7   5.5   305   20   10   8.0   4.4   14.2  57.6    -3.4    860  4.4
 14500  -13.5   7.7   305   21   11   8.0   4.4   13.9  57.0    -3.7    809  4.1
 14000  -12.4   9.7   300   22   11   8.0   4.4   13.6  56.6    -4.0    759  3.9
 13500  -11.2  11.8   300   23   12   8.0   4.4   13.3  56.0    -4.3    708  3.6
 13000  -10.0  14.0   300   24   12   8.0   4.4   13.1  55.5    -4.6    658  3.3
 12500   -8.8  16.2   295   25   13   8.1   4.4   12.8  55.0    -4.9    608  3.1
 12000   -7.6  18.3   295   25   13   8.1   4.4   12.5  54.6    -5.2    557  2.8
 11500   -6.4  20.5   295   25   13   8.1   4.5   12.3  54.1    -5.5    506  2.6
 11000   -5.2  22.6   290   26   13   7.9   4.3   12.0  53.6    -5.7    456  2.3
 10500   -4.2  24.4   290   25   13   6.6   3.6   11.6  52.8    -6.2    410  2.1
 10250   -3.7  25.3   290   25   13   6.6   3.6   11.3  52.4    -6.5    388  2.0
 10000   -3.1  26.4   290   25   13  11.3   6.2   11.2  52.2    -6.6    363  1.8
  9750   -2.1  28.2   290   24   12  11.5   6.3   11.5  52.6    -6.4    326  1.7
  9500   -1.5  29.3   290   23   12   7.9   4.3   11.4  52.5    -6.5    300  1.5
  9250   -0.8  30.6   290   23   12   9.4   5.1   11.3  52.3    -6.6    273  1.4
  9000   -0.2  31.6   290   22   11   7.0   3.8   11.2  52.2    -6.7    246  1.3
  8750    0.3  32.5   290   21   11   7.5   4.1   10.9  51.7    -7.0    225  1.1
  8500    1.0  33.8   290   20   10   9.9   5.4   10.9  51.6    -7.1    197  1.0
  8250    1.7  35.1   290   20   10   9.1   5.0   10.9  51.6    -7.1    169  0.9
  8000    2.3  36.1   290   19   10   8.0   4.4   10.8  51.4    -7.2    142  0.7
  7750    2.9  37.2   290   17    9   8.4   4.6   10.6  51.2    -7.4    118  0.6
  7500    3.6  38.5   285   16    8   9.9   5.4   10.6  51.1    -7.4     89  0.5
  7250    4.3  39.7   285   15    8   8.4   4.6   10.6  51.1    -7.5     61  0.3
  7000    4.8  40.6   285   13    7   6.2   3.4   10.4  50.7    -7.7     38  0.2
  6750    5.3  41.5   285   12    6   7.9   4.3   10.2  50.3    -8.0     15  0.1
  6500    6.0  42.8   275   10    5   8.9   4.9   10.1  50.2    -8.0      M    M
  6250    6.5  43.7   270    9    5   4.6   2.5    9.9  49.8    -8.3      M    M
  6000    6.7  44.1   260    7    4   1.4   0.8    9.3  48.8    -8.8      M    M
  5750    6.9  44.4   245    6    3   4.7   2.6    8.8  47.8    -9.4      M    M
  5500    6.9  44.4   230    7    3 -11.5  -6.3    8.1  46.6   -10.1      M    M

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

           03/12/2024 at 0900 MDT          |       03/12/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +6.4        | CAPE...     0.0    LI...       +5.6
CINH...     0.0    K Index...  -5.1        | CINH...    -0.1    K Index...  -2.2
                                           |
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 -57.2 -71.0  260  28 14   1.6   0.9 | -57.0 -70.6  260  30 15   0.7   0.4
 45000 -54.6 -66.3  275  36 18   2.1   1.2 | -55.8 -68.4  270  32 17   1.1   0.6
 40000 -60.6 -77.1  285  55 28  -4.4  -2.4 | -59.8 -75.6  270  50 26  -2.9  -1.6
 38000 -61.6 -78.9  290  57 30   4.1   2.3 | -60.5 -76.9  270  55 28   2.4   1.3
 36000 -59.0 -74.2  295  49 25   4.3   2.3 | -59.0 -74.2  270  53 27   2.5   1.4
 34000 -56.5 -69.7  310  41 21   5.8   3.2 | -57.6 -71.7  265  52 27   5.4   3.0
 32000 -51.2 -60.2  310  42 22   7.8   4.3 | -51.8 -61.2  265  47 24   8.6   4.7
 30000 -46.5 -51.7  310  43 22   8.9   4.9 | -46.6 -51.9  270  43 22   8.8   4.8
 29000 -43.8 -46.8  310  42 22   8.8   4.8 | -44.0 -47.2  270  40 21   8.8   4.8
 28000 -41.2 -42.2  310  42 22   8.8   4.8 | -41.3 -42.3  270  38 20   8.8   4.8
 27000 -38.5 -37.3  310  41 21   8.8   4.8 | -38.7 -37.7  270  36 18   8.8   4.8
 26000 -36.0 -32.8  310  41 21   8.6   4.7 | -36.2 -33.2  270  35 18   8.3   4.6
 25000 -33.4 -28.1  310  40 21   8.6   4.7 | -33.7 -28.7  270  33 17   8.3   4.6
 24000 -30.8 -23.4  310  40 20   8.7   4.8 | -31.2 -24.2  270  32 17   8.4   4.6
 23000 -28.5 -19.3  305  39 20   7.6   4.2 | -28.9 -20.0  270  32 16   7.7   4.2
 22000 -26.2 -15.2  305  39 20   7.6   4.2 | -26.6 -15.9  270  31 16   7.7   4.2
 21000 -23.9 -11.0  305  38 20   7.5   4.1 | -24.3 -11.7  270  31 16   7.8   4.3
 20000 -21.8  -7.2  305  37 19   6.9   3.8 | -21.9  -7.4  275  30 15   7.9   4.3
 19500 -20.8  -5.4  305  36 19   6.9   3.8 | -20.7  -5.3  275  29 15   7.9   4.3
 19000 -19.7  -3.5  305  36 18   6.9   3.8 | -19.6  -3.3  275  29 15   7.9   4.3
 18500 -18.7  -1.7  310  35 18   6.9   3.8 | -18.4  -1.1  275  28 15   7.8   4.3
 18000 -17.8  -0.0  310  34 17   5.4   3.0 | -17.2   1.0  280  27 14   7.6   4.2
 17500 -17.0   1.4  310  32 16   5.6   3.1 | -16.1   3.0  280  26 14   7.7   4.2
 17000 -16.2   2.8  310  30 15   4.9   2.7 | -14.9   5.2  280  25 13   6.7   3.7
 16500 -15.1   4.8  310  26 13   4.6   2.5 | -13.5   7.7  280  24 12   6.6   3.6
 16000 -14.4   6.1  310  23 12   4.9   2.7 | -12.6   9.3  285  23 12   5.1   2.8
 15500 -13.7   7.3  310  20 10   4.9   2.7 | -11.9  10.6  285  22 11   5.0   2.8
 15000 -13.0   8.6  310  17  9   5.6   3.1 | -11.1  12.0  285  20 11   4.9   2.7
 14500 -12.1  10.2  310  16  8   6.1   3.3 | -10.4  13.3  285  19 10   4.8   2.6
 14000 -11.2  11.8  315  14  7   6.4   3.5 |  -9.7  14.5  285  18  9   4.8   2.6
 13500 -10.1  13.8  315  14  7   7.0   3.8 |  -9.0  15.8  285  16  8   4.8   2.7
 13000  -9.1  15.6  320  14  7   7.1   3.9 |  -8.3  17.1  285  15  8   5.2   2.9
 12500  -8.0  17.6  315  15  8   7.5   4.1 |  -7.4  18.7  280  13  7   6.4   3.5
 12000  -6.9  19.6  315  15  8   7.5   4.1 |  -6.5  20.3  280  11  6   6.7   3.7
 11500  -5.8  21.6  315  16  8   7.7   4.2 |  -5.4  22.3  275  10  5   8.0   4.4
 11000  -4.7  23.5  310  16  8   7.4   4.1 |  -4.2  24.4  275   9  5   7.7   4.2
 10500  -3.7  25.3  310  17  9   6.5   3.6 |  -3.2  26.2  275   9  5   6.5   3.6
 10250  -3.2  26.2  305  18  9   6.3   3.5 |  -2.7  27.1  275   9  5   7.9   4.3
 10000  -2.6  27.3  305  19 10  10.1   5.5 |  -1.9  28.6  280   9  5  11.4   6.3
  9750  -1.8  28.8  300  19 10   9.7   5.3 |  -1.1  30.0  280   9  5  10.0   5.5
  9500  -1.3  29.7  300  19 10   6.3   3.4 |  -0.5  31.1  280  10  5   7.6   4.2
  9250  -0.8  30.6  295  20 10   7.4   4.0 |   0.1  32.2  285  10  5   8.5   4.7
  9000  -0.3  31.5  295  21 11   5.1   2.8 |   0.7  33.3  285  10  5   6.8   3.7
  8750   0.0  32.0  295  20 11   6.4   3.5 |   1.1  34.0  280  10  5   7.4   4.1
  8500   0.6  33.1  290  20 10   9.1   5.0 |   1.8  35.2  280   9  5   9.4   5.2
  8250   1.3  34.3  290  19 10   7.9   4.3 |   2.5  36.5  275   8  4   8.5   4.7
  8000   1.8  35.2  290  17  9   6.4   3.5 |   3.0  37.4  275   7  4   7.6   4.1
  7750   2.3  36.1  290  16  8   8.2   4.5 |   3.6  38.5  270   6  3   8.9   4.9
  7500   3.0  37.4  285  15  8  11.0   6.0 |   4.4  39.9  270   6  3  10.7   5.9
  7250   3.8  38.8  285  13  7   8.2   4.5 |   5.1  41.2  265   6  3   9.0   5.0
  7000   4.2  39.6  285  12  6   5.0   2.7 |   5.7  42.3  265   5  3   7.1   3.9
  6750   4.7  40.5  280  11  5   8.3   4.6 |   6.3  43.3  265   5  3  10.1   5.6
  6500   5.4  41.7  275   9  5   9.4   5.2 |   7.2  45.0  265   5  2  12.3   6.8
  6250   5.9  42.6  270   8  4   4.8   2.6 |   8.0  46.4  265   5  2  10.3   5.6
  6000   6.2  43.2  255   7  4   3.2   1.8 |   8.8  47.8  265   4  2   9.8   5.4
  5750   6.5  43.7  240   6  3   3.9   2.1 |   9.5  49.1  265   4  2   9.6   5.3
  5500   6.7  44.1  225   6  3   0.2   0.1 |  10.3  50.5  265   4  2  14.1   7.7

           03/12/2024 at 1500 MDT          |       03/12/2024 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +3.5        | CAPE...     0.0    LI...       +1.7
CINH...    -0.1    K Index...  +9.2        | CINH...    -0.1    K Index... +18.4
                                           |
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 -56.8 -70.2  265  32 17   0.7   0.4 | -56.6 -69.9  265  33 17   0.9   0.5
 45000 -55.7 -68.3  270  33 17   1.1   0.6 | -55.2 -67.4  265  37 19   1.3   0.7
 40000 -59.3 -74.7  265  50 26  -2.6  -1.4 | -59.5 -75.1  260  57 29  -3.1  -1.7
 38000 -59.8 -75.6  265  55 28   2.5   1.4 | -60.3 -76.5  255  63 32   2.6   1.4
 36000 -58.3 -72.9  270  55 28   2.5   1.4 | -58.7 -73.7  260  65 33   2.6   1.4
 34000 -56.7 -70.1  270  55 28   5.8   3.2 | -57.1 -70.8  260  67 34   5.9   3.2
 32000 -51.7 -61.1  265  52 27   8.4   4.6 | -51.7 -61.1  260  59 30   9.1   5.0
 30000 -46.0 -50.8  260  48 25   8.7   4.8 | -45.7 -50.3  255  50 26   8.5   4.6
 29000 -43.4 -46.1  260  46 24   8.7   4.8 | -43.1 -45.6  255  48 24   8.5   4.7
 28000 -40.8 -41.4  260  44 23   8.7   4.8 | -40.5 -40.9  255  45 23   8.5   4.7
 27000 -38.2 -36.8  260  42 22   8.7   4.8 | -38.0 -36.4  255  42 22   8.5   4.7
 26000 -35.7 -32.3  260  42 22   8.6   4.7 | -35.7 -32.3  255  41 21   7.7   4.2
 25000 -33.1 -27.6  260  42 22   8.6   4.7 | -33.4 -28.1  260  40 20   7.7   4.2
 24000 -30.6 -23.1  260  42 22   8.7   4.8 | -31.1 -24.0  260  39 20   7.8   4.3
 23000 -28.3 -18.9  265  41 21   7.4   4.1 | -28.9 -20.0  260  38 19   7.3   4.0
 22000 -26.1 -15.0  265  39 20   7.4   4.1 | -26.7 -16.1  260  37 19   7.3   4.0
 21000 -23.9 -11.0  265  37 19   7.2   3.9 | -24.5 -12.1  260  36 18   7.2   3.9
 20000 -21.9  -7.4  265  35 18   6.6   3.6 | -22.5  -8.5  260  33 17   6.6   3.6
 19500 -20.9  -5.6  265  34 17   6.6   3.6 | -21.6  -6.9  260  32 17   6.6   3.6
 19000 -19.9  -3.8  265  33 17   6.6   3.6 | -20.6  -5.1  260  31 16   6.6   3.6
 18500 -18.9  -2.0  265  32 16   6.6   3.6 | -19.6  -3.3  260  30 15   6.6   3.6
 18000 -17.9  -0.2  260  30 16   6.1   3.4 | -18.7  -1.7  260  28 14   6.5   3.5
 17500 -17.0   1.4  260  29 15   6.2   3.4 | -17.7   0.1  255  26 13   6.5   3.6
 17000 -16.1   3.0  260  28 14   5.9   3.2 | -16.8   1.8  250  24 12   6.5   3.6
 16500 -15.3   4.5  260  25 13   5.8   3.2 | -15.8   3.6  245  23 12   6.6   3.6
 16000 -14.4   6.1  260  23 12   6.3   3.5 | -14.3   6.3  240  21 11   7.2   4.0
 15500 -12.8   9.0  255  21 11   7.3   4.0 | -13.3   8.1  235  20 10   7.3   4.0
 15000 -11.7  10.9  255  19 10   7.5   4.1 | -12.2  10.0  235  18  9   7.9   4.3
 14500 -10.6  12.9  255  19 10   7.5   4.1 | -10.9  12.4  230  17  9   8.3   4.5
 14000  -9.5  14.9  255  18  9   7.2   4.0 |  -9.7  14.5  225  16  8   8.3   4.6
 13500  -8.5  16.7  255  17  9   6.8   3.8 |  -8.5  16.7  225  15  8   8.4   4.6
 13000  -7.5  18.5  255  16  8   6.9   3.8 |  -7.2  19.0  220  14  7   8.5   4.7
 12500  -6.5  20.3  255  15  8   7.0   3.9 |  -5.9  21.4  220  13  7   9.0   4.9
 12000  -5.4  22.3  255  13  7   7.3   4.0 |  -4.6  23.7  220  12  6   8.9   4.9
 11500  -4.3  24.3  255  12  6   8.3   4.5 |  -3.2  26.2  215  10  5   8.7   4.8
 11000  -3.0  26.6  255  10  5   7.8   4.3 |  -1.9  28.6  205   9  5   8.5   4.6
 10500  -2.0  28.4  255   9  4   6.0   3.3 |  -0.8  30.6  200   7  4   6.8   3.7
 10250  -1.5  29.3  255   8  4   8.6   4.7 |  -0.2  31.6  200   7  3   8.9   4.9
 10000  -0.7  30.7  250   7  4  12.2   6.7 |   0.6  33.1  195   6  3  11.4   6.3
  9750   0.2  32.4  250   6  3   9.9   5.4 |   1.3  34.3  190   5  2   9.0   4.9
  9500   0.8  33.4  250   6  3   8.0   4.4 |   1.9  35.4  185   4  2   7.6   4.2
  9250   1.4  34.5  250   5  3   8.9   4.9 |   2.5  36.5  175   3  1   7.5   4.1
  9000   2.0  35.6  250   4  2   7.0   3.9 |   3.1  37.6  155   2  1   9.3   5.1
  8750   2.5  36.5  260   4  2   8.1   4.4 |   3.9  39.0  155   2  1  10.0   5.5
  8500   3.3  37.9  260   4  2  10.8   5.9 |   4.5  40.1  130   1  1   8.4   4.6
  8250   4.0  39.2  265   3  2   9.4   5.2 |   5.2  41.4  090   1  1   8.7   4.8
  8000   4.7  40.5  270   3  2   7.6   4.2 |   5.8  42.4  060   2  1   7.9   4.3
  7750   5.3  41.5  280   3  2   9.4   5.2 |   6.4  43.5  050   2  1   8.9   4.9
  7500   6.1  43.0  280   3  1  12.3   6.7 |   7.1  44.8  040   2  1  10.5   5.7
  7250   7.0  44.6  275   3  1   9.5   5.2 |   7.9  46.2  035   3  1   9.2   5.0
  7000   7.5  45.5  285   3  1   6.2   3.4 |   8.5  47.3  030   3  2   7.1   3.9
  6750   8.1  46.6  295   3  1  10.1   5.6 |   9.1  48.4  030   4  2   9.5   5.2
  6500   9.0  48.2  290   2  1  13.3   7.3 |   9.9  49.8  025   4  2  12.3   6.8
  6250   9.9  49.8  290   2  1  10.2   5.6 |  10.8  51.4  025   4  2   9.9   5.4
  6000  10.6  51.1  300   2  1   8.6   4.7 |  11.4  52.5  025   4  2   8.1   4.4
  5750  11.3  52.3  305   3  1  10.2   5.6 |  12.1  53.8  025   5  2   9.6   5.3
  5500  12.2  54.0  295   2  1  16.8   9.2 |  12.8  55.0  020   4  2  11.2   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.

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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