Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 171335
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0734 MDT Sunday, March 17, 2024

This forecast is for Sunday, March 17, 2024:

If the trigger temperature of 43.5 F/6.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 294 ft/min (1.5 m/s)
   Maximum height of thermals.................. 11569 ft MSL (6269 ft AGL)

Forecast maximum temperature................... 47.0 F/8.8 C
Time of trigger temperature.................... 1245 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7251 ft MSL (1952 ft AGL)
Thermal soaring outlook for Monday 03/18....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Becoming poor
Height of stable layer (12-18K ft MSL)......... 13685 ft MSL (8385 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 14178 ft MSL (8878 ft AGL)
Wave soaring outlook for Monday 03/18.......... Poor

Remarks...

Sunrise/Sunset.................... 07:06:18 / 19:08:49 MDT
Total possible sunshine........... 12 hr 2 min 31 sec (722 min 31 sec)
Altitude of sun at 13:07:34 MDT... 49.27 degrees

Upper air data from numerical model forecast valid on 03/17/2024 at 0600 MDT

Freezing level.................. 6923 ft MSL (1623 ft AGL)
Convective condensation level... 10527 ft MSL (5227 ft AGL)
Lifted condensation level....... 11127 ft MSL (5827 ft AGL)
Lifted index.................... +7.2
K index......................... +12.5

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -57.2 -71.0   265   35   18   1.8   1.0      M     M       M      M    M
 45000  -54.5 -66.1   260   38   19   2.3   1.2      M     M       M      M    M
 40000  -59.0 -74.2   250   24   12  -3.3  -1.8      M     M       M      M    M
 38000  -59.5 -75.1   240   18    9   4.6   2.5      M     M       M      M    M
 36000  -56.3 -69.3   215   12    6   4.7   2.6      M     M       M      M    M
 34000  -53.4 -64.1   165    9    5   6.1   3.3      M     M       M      M    M
 32000  -49.8 -57.6   070   13    7   6.0   3.3      M     M       M      M    M
 30000  -46.1 -51.0   055   27   14   6.7   3.7   30.6  87.0    16.6      M    M
 29000  -44.2 -47.6   055   27   14   6.6   3.6   29.2  84.5    15.8      M    M
 28000  -42.2 -44.0   060   27   14   6.6   3.6   27.9  82.3    15.0      M    M
 27000  -40.2 -40.4   060   28   14   6.6   3.6   26.9  80.3    14.4      M    M
 26000  -37.8 -36.0   055   27   14   8.2   4.5   26.1  78.9    13.9      M    M
 25000  -35.4 -31.7   055   27   14   8.2   4.5   25.5  77.8    13.6      M    M
 24000  -32.9 -27.2   050   27   14   8.4   4.6   25.0  77.0    13.4      M    M
 23000  -30.9 -23.6   050   24   12   6.2   3.4   23.8  74.9    12.6      M    M
 22000  -29.0 -20.2   050   20   11   6.2   3.4   22.5  72.5    11.6      M    M
 21000  -27.2 -17.0   050   17    9   6.6   3.6   21.3  70.3    10.7      M    M
 20000  -24.9 -12.8   040   12    6   7.7   4.2   20.4  68.8    10.1      M    M
 19500  -23.8 -10.8   030   11    5   7.7   4.2   20.1  68.1     9.9      M    M
 19000  -22.6  -8.7   020    9    5   7.7   4.2   19.7  67.5     9.6      M    M
 18500  -21.5  -6.7   360    9    4   7.8   4.3   19.4  66.9     9.4      M    M
 18000  -19.6  -3.3   355    8    4   8.7   4.7   19.1  66.3     9.2      M    M
 17500  -18.3  -0.9   350    8    4   8.2   4.5   18.9  66.0     9.1      M    M
 17000  -17.2   1.0   350    7    3   6.8   3.7   18.5  65.2     8.7      M    M
 16500  -16.2   2.8   350    5    3   7.2   4.0   18.0  64.3     8.3      M    M
 16000  -15.4   4.3   355    5    2   3.6   2.0   17.2  63.0     7.7      M    M
 15500  -14.8   5.4   355    5    3   3.9   2.1   16.3  61.3     6.8      M    M
 15000  -14.2   6.4   355    6    3   6.0   3.3   15.4  59.7     6.1      M    M
 14500  -13.2   8.2   360    7    4   6.3   3.5   14.8  58.7     5.6      M    M
 14000  -12.3   9.9   360    8    4   3.5   1.9   14.2  57.6     5.1      M    M
 13500  -12.1  10.2   005    9    4   1.9   1.1   12.9  55.2     3.9      M    M
 13000  -11.8  10.8   010    9    5   2.6   1.4   11.6  52.8     2.7      M    M
 12500  -11.4  11.5   010   10    5   3.3   1.8   10.5  50.9     1.7      M    M
 12000  -10.9  12.4   010   10    5   3.6   2.0    9.5  49.1     0.7      M    M
 11500  -10.3  13.5   015   12    6   3.8   2.1    8.5  47.4    -0.2    487  2.5
 11000   -9.7  14.5   015   12    6   6.1   3.4    7.7  45.8    -1.0    454  2.3
 10500   -8.6  16.5   010   12    6   7.8   4.3    7.3  45.1    -1.4    406  2.1
 10250   -8.0  17.6   010   12    6   6.5   3.6    7.1  44.8    -1.6    382  1.9
 10000   -7.6  18.3   010   12    6   5.6   3.1    6.8  44.2    -1.9    363  1.8
  9750   -7.1  19.2   010   12    6   9.7   5.3    6.6  43.9    -2.1    339  1.7
  9500   -6.2  20.8   010   12    6  12.7   7.0    6.8  44.2    -2.0    305  1.6
  9250   -5.3  22.5   010   12    6   9.8   5.4    6.9  44.5    -1.8    272  1.4
  9000   -4.8  23.4   010   12    6   6.6   3.6    6.8  44.2    -2.0    247  1.3
  8750   -4.2  24.4   010   12    6   9.1   5.0    6.6  43.8    -2.2    223  1.1
  8500   -3.4  25.9   010   13    6  11.1   6.1    6.7  44.0    -2.1    191  1.0
  8250   -2.7  27.1   015   13    7   8.5   4.7    6.7  44.0    -2.1    161  0.8
  8000   -2.1  28.2   015   13    7   7.3   4.0    6.5  43.7    -2.3    137  0.7
  7750   -1.5  29.3   015   13    7   7.2   4.0    6.3  43.4    -2.4    112  0.6
  7500   -1.0  30.2   015   13    7   6.1   3.4    6.1  42.9    -2.7     90  0.5
  7250   -0.6  30.9   015   13    7   5.6   3.1    5.8  42.4    -3.0     70  0.4
  7000   -0.2  31.6   010   13    6   5.7   3.1    5.5  41.8    -3.3     50  0.3
  6750    0.2  32.4   010   12    6   5.0   2.8    5.1  41.3    -3.6     30  0.2
  6500    0.5  32.9   010   11    6   3.7   2.0    4.7  40.5    -4.1     14  0.1
  6250    0.8  33.4   005   11    6   3.2   1.8    4.2  39.6    -4.6      M    M
  6000    1.0  33.8   360   11    6   3.8   2.1    3.7  38.7    -5.1      M    M
  5750    1.2  34.2   350   10    5   2.5   1.3    3.3  37.9    -5.6      M    M
  5500    1.2  34.2   335    6    3  -1.2  -0.7    2.6  36.7    -6.4      M    M

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

           03/17/2024 at 0900 MDT          |       03/17/2024 at 1200 MDT
                                           |
CAPE...    +0.3    LI...       +6.5        | CAPE...   +20.7    LI...       +7.1
CINH...    -5.3    K Index... +10.8        | CINH...    -0.5    K Index...  +8.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -56.4 -69.5  275  35 18   1.4   0.8 | -56.9 -70.4  275  28 14   1.5   0.8
 45000 -54.2 -65.6  265  37 19   1.7   0.9 | -54.7 -66.5  270  32 16   1.8   1.0
 40000 -58.6 -73.5  265  18 10  -3.1  -1.7 | -57.7 -71.9  275  15  8  -2.2  -1.2
 38000 -59.0 -74.2  270  11  5   3.2   1.8 | -58.2 -72.8  295  10  5   2.5   1.4
 36000 -57.1 -70.8  305   3  2   3.2   1.8 | -56.4 -69.5  335  10  5   2.5   1.4
 34000 -55.1 -67.2  050   7  4   5.2   2.9 | -54.8 -66.6  360  14  7   5.1   2.8
 32000 -51.4 -60.5  040  18  9   6.2   3.4 | -51.6 -60.9  030  22 11   5.3   2.9
 30000 -47.7 -53.9  035  28 15   7.6   4.2 | -48.2 -54.8  040  31 16   8.5   4.7
 29000 -45.3 -49.5  040  28 15   7.7   4.3 | -45.8 -50.4  040  31 16   8.2   4.5
 28000 -43.0 -45.4  040  28 15   7.8   4.3 | -43.3 -45.9  040  32 16   8.2   4.5
 27000 -40.1 -40.2  045  28 15   7.7   4.2 | -40.9 -41.6  040  33 17   8.1   4.5
 26000 -37.8 -36.0  045  30 15   7.7   4.2 | -38.5 -37.3  040  33 17   7.9   4.3
 25000 -35.5 -31.9  050  31 16   7.7   4.2 | -36.1 -33.0  040  33 17   7.9   4.3
 24000 -33.2 -27.8  050  32 17   7.7   4.2 | -33.7 -28.7  035  33 17   7.9   4.3
 23000 -31.0 -23.8  055  30 15   7.6   4.1 | -31.2 -24.2  040  31 16   8.4   4.6
 22000 -28.7 -19.7  055  27 14   7.6   4.2 | -28.7 -19.7  040  28 14   8.4   4.6
 21000 -26.5 -15.7  060  24 13   7.4   4.1 | -26.2 -15.2  045  25 13   8.0   4.4
 20000 -24.3 -11.7  055  20 10   7.3   4.0 | -23.9 -11.0  050  20 11   7.5   4.1
 19500 -23.2  -9.8  055  18  9   7.3   4.0 | -22.8  -9.0  055  18  9   7.5   4.1
 19000 -22.2  -8.0  050  16  8   7.3   4.0 | -21.7  -7.1  060  16  8   7.5   4.1
 18500 -21.1  -6.0  050  14  7   7.2   4.0 | -20.6  -5.1  070  14  7   7.3   4.0
 18000 -20.0  -4.0  045  13  7   7.1   3.9 | -19.6  -3.3  065  12  6   6.5   3.6
 17500 -19.0  -2.2  045  11  6   7.2   3.9 | -18.7  -1.7  055  10  5   6.6   3.6
 17000 -18.0  -0.4  040  10  5   6.2   3.4 | -17.3   0.9  040   8  4   5.8   3.2
 16500 -17.1   1.2  040   8  4   6.3   3.5 | -16.5   2.3  025   8  4   5.8   3.2
 16000 -16.1   3.0  035   6  3   7.2   3.9 | -15.5   4.1  015   7  4   7.0   3.8
 15500 -15.0   5.0  025   5  3   7.4   4.1 | -14.5   5.9  005   8  4   7.0   3.9
 15000 -13.9   7.0  010   5  2   7.0   3.8 | -13.6   7.5  005   8  4   4.8   2.7
 14500 -12.9   8.8  010   6  3   6.1   3.4 | -12.9   8.8  005   9  5   4.8   2.6
 14000 -11.8  10.8  010   8  4   1.8   1.0 | -12.2  10.0  005  10  5   3.4   1.9
 13500 -11.7  10.9  010   8  4   0.8   0.5 | -11.8  10.8  005  11  6   3.0   1.6
 13000 -11.5  11.3  005   9  5   1.8   1.0 | -11.4  11.5  005  12  6   2.6   1.4
 12500 -11.2  11.8  005  10  5   2.2   1.2 | -11.1  12.0  360  12  6   2.4   1.3
 12000 -10.9  12.4  360  11  6   3.0   1.6 | -10.7  12.7  360  12  6   2.3   1.3
 11500 -10.4  13.3  360  12  6   3.3   1.8 | -10.4  13.3  360  13  6   2.2   1.2
 11000  -9.9  14.2  360  12  6   4.6   2.5 | -10.0  14.0  360  13  7   4.4   2.4
 10500  -9.2  15.4  360  13  7   5.2   2.9 |  -9.2  15.4  005  13  7   5.5   3.0
 10250  -8.8  16.2  360  13  7   3.8   2.1 |  -8.8  16.2  005  13  7   4.0   2.2
 10000  -8.6  16.5  355  13  7   4.5   2.5 |  -8.6  16.5  005  13  7   3.0   1.7
  9750  -8.1  17.4  355  13  7   9.9   5.4 |  -8.3  17.1  360  12  6   7.5   4.1
  9500  -7.2  19.0  360  14  7  12.9   7.1 |  -7.6  18.3  360  12  6  10.6   5.8
  9250  -6.3  20.7  360  14  7   9.1   5.0 |  -6.9  19.6  355  11  6   8.2   4.5
  9000  -5.9  21.4  360  14  7   6.0   3.3 |  -6.3  20.7  355  11  5   6.3   3.4
  8750  -5.3  22.5  360  14  7   8.4   4.6 |  -5.8  21.6  350  10  5   8.9   4.9
  8500  -4.6  23.7  360  14  7   9.2   5.0 |  -5.1  22.8  350   9  5  10.1   5.6
  8250  -4.0  24.8  005  14  7   8.2   4.5 |  -4.4  24.1  345   9  4   8.3   4.6
  8000  -3.4  25.9  005  14  7   7.2   3.9 |  -3.8  25.2  345   8  4   7.7   4.2
  7750  -2.8  27.0  010  14  7   9.8   5.4 |  -3.2  26.2  345   7  4   8.4   4.6
  7500  -2.0  28.4  010  14  7   8.8   4.8 |  -2.5  27.5  345   6  3   8.7   4.8
  7250  -1.5  29.3  010  13  7   5.3   2.9 |  -1.9  28.6  345   6  3   8.4   4.6
  7000  -1.0  30.2  015  13  6   6.3   3.5 |  -1.3  29.7  345   5  3   8.6   4.7
  6750  -0.6  30.9  015  12  6   5.5   3.0 |  -0.7  30.7  340   5  2   8.1   4.4
  6500  -0.2  31.6  010  11  5   4.6   2.5 |  -0.1  31.8  335   4  2   9.1   5.0
  6250   0.0  32.0  015  10  5   4.0   2.2 |   0.6  33.1  335   4  2  10.2   5.6
  6000   0.3  32.5  015   9  5   5.2   2.9 |   1.4  34.5  335   4  2   9.9   5.4
  5750   0.8  33.4  015   8  4   8.5   4.7 |   2.2  36.0  330   4  2  13.3   7.3
  5500   1.4  34.5  010   6  3  10.6   5.8 |   3.4  38.1  330   4  2  18.5  10.2

           03/17/2024 at 1500 MDT          |       03/17/2024 at 1800 MDT
                                           |
CAPE...   +21.5    LI...       +6.1        | CAPE...    +0.9    LI...       +4.6
CINH...    -0.1    K Index...  +5.0        | CINH...    -0.0    K Index...  -1.9
                                           |
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 -56.3 -69.3  275  25 13   1.3   0.7 | -56.3 -69.3  285  24 13   0.8   0.4
 45000 -54.4 -65.9  270  28 14   1.5   0.8 | -55.1 -67.2  285  23 12   1.0   0.6
 40000 -57.5 -71.5  325  10  5  -2.2  -1.2 | -57.9 -72.2  345  16  8  -2.1  -1.1
 38000 -57.9 -72.2  005  13  7   1.5   0.8 | -58.5 -73.3  015  22 11   1.3   0.7
 36000 -57.0 -70.6  015  21 11   1.5   0.8 | -57.8 -72.0  025  35 18   1.3   0.7
 34000 -56.0 -68.8  020  29 15   4.8   2.6 | -57.0 -70.6  035  49 25   3.4   1.8
 32000 -52.3 -62.1  020  31 16   6.2   3.4 | -52.4 -62.3  035  44 23   6.8   3.7
 30000 -48.5 -55.3  025  33 17   7.9   4.3 | -48.2 -54.8  035  40 21   8.8   4.8
 29000 -46.1 -51.0  025  33 17   8.0   4.4 | -45.6 -50.1  035  38 19   8.6   4.7
 28000 -43.7 -46.7  020  32 17   8.0   4.4 | -43.0 -45.4  035  36 18   8.6   4.7
 27000 -40.7 -41.3  020  32 16   8.2   4.5 | -40.4 -40.7  035  33 17   8.6   4.7
 26000 -38.1 -36.6  020  32 16   8.5   4.6 | -37.9 -36.2  030  32 17   8.1   4.5
 25000 -35.6 -32.1  020  32 17   8.5   4.6 | -35.5 -31.9  025  32 16   8.1   4.5
 24000 -33.1 -27.6  020  32 17   8.3   4.6 | -33.1 -27.6  020  31 16   8.2   4.5
 23000 -30.8 -23.4  020  30 16   7.4   4.1 | -30.9 -23.6  015  30 16   7.2   3.9
 22000 -28.6 -19.5  020  28 14   7.4   4.1 | -28.7 -19.7  010  29 15   7.2   4.0
 21000 -26.4 -15.5  020  25 13   8.0   4.4 | -26.6 -15.9  010  28 14   7.2   3.9
 20000 -23.9 -11.0  020  19 10   8.2   4.5 | -24.4 -11.9  005  24 12   7.1   3.9
 19500 -22.7  -8.9  020  16  8   8.2   4.5 | -23.4 -10.1  360  22 11   7.1   3.9
 19000 -21.4  -6.5  015  13  7   8.2   4.5 | -22.3  -8.1  360  20 10   7.2   3.9
 18500 -20.2  -4.4  015  10  5   8.0   4.4 | -21.2  -6.2  355  18  9   7.7   4.2
 18000 -19.0  -2.2  015  10  5   7.8   4.3 | -19.9  -3.8  350  17  9   8.7   4.8
 17500 -17.9  -0.2  015  10  5   7.9   4.3 | -18.6  -1.5  345  16  8   8.8   4.8
 17000 -16.8   1.8  010  10  5   6.7   3.7 | -17.3   0.9  340  16  8   8.4   4.6
 16500 -15.8   3.6  010  10  5   6.9   3.8 | -15.4   4.3  335  15  8   8.3   4.6
 16000 -14.8   5.4  005  10  5   5.9   3.2 | -14.4   6.1  335  16  8   5.5   3.0
 15500 -14.0   6.8  360  10  5   5.6   3.1 | -13.6   7.5  335  17  9   5.8   3.2
 15000 -13.2   8.2  350  10  5   5.5   3.0 | -12.8   9.0  335  18  9   4.8   2.7
 14500 -12.4   9.7  350  10  5   5.3   2.9 | -12.1  10.2  335  18  9   4.9   2.7
 14000 -11.7  10.9  345  11  5   4.9   2.7 | -11.4  11.5  335  18  9   4.1   2.3
 13500 -10.8  12.6  340  11  6   3.8   2.1 | -10.8  12.6  335  18  9   3.9   2.2
 13000 -10.3  13.5  340  11  6   2.6   1.4 | -10.3  13.5  335  17  9   3.8   2.1
 12500 -10.0  14.0  340  10  5   2.3   1.3 |  -9.7  14.5  335  17  9   3.8   2.1
 12000  -9.7  14.5  340  10  5   1.7   0.9 |  -9.2  15.4  335  17  9   4.4   2.4
 11500  -9.5  14.9  350  10  5   1.4   0.7 |  -8.5  16.7  340  17  9   4.6   2.5
 11000  -9.2  15.4  360  11  6   4.7   2.6 |  -7.8  18.0  345  17  9   5.8   3.2
 10500  -8.4  16.9  360  11  6   5.8   3.2 |  -6.9  19.6  345  18  9   6.6   3.6
 10250  -8.0  17.6  360  11  6   4.1   2.3 |  -6.4  20.5  350  18  9   4.9   2.7
 10000  -7.7  18.1  360  11  6   4.6   2.5 |  -6.1  21.0  350  18  9   4.0   2.2
  9750  -7.2  19.0  355  10  5   9.0   5.0 |  -5.7  21.7  350  16  8   6.6   3.6
  9500  -6.5  20.3  355   9  5  10.8   5.9 |  -5.2  22.6  355  14  7   8.1   4.5
  9250  -5.7  21.7  350   8  4   8.1   4.5 |  -4.7  23.5  355  12  6   6.4   3.5
  9000  -5.3  22.5  350   7  4   6.1   3.4 |  -4.3  24.3  360  11  5   4.9   2.7
  8750  -4.7  23.5  345   7  3   8.4   4.6 |  -3.9  25.0  360  10  5   7.3   4.0
  8500  -4.1  24.6  340   6  3   9.2   5.0 |  -3.2  26.2  005   9  4   8.6   4.7
  8250  -3.4  25.9  335   5  3   8.4   4.6 |  -2.7  27.1  005   8  4   7.8   4.3
  8000  -2.8  27.0  335   5  2   8.0   4.4 |  -2.1  28.2  005   7  4   7.2   4.0
  7750  -2.2  28.0  330   5  2   9.1   5.0 |  -1.6  29.1  005   7  3   9.0   4.9
  7500  -1.6  29.1  330   4  2   9.8   5.4 |  -0.8  30.6  005   6  3   9.6   5.3
  7250  -0.9  30.4  330   4  2   9.5   5.2 |  -0.2  31.6  360   6  3   8.6   4.7
  7000  -0.2  31.6  330   4  2   9.4   5.1 |   0.4  32.7  360   6  3   8.2   4.5
  6750   0.5  32.9  325   4  2  10.2   5.6 |   1.0  33.8  355   6  3  10.4   5.7
  6500   1.3  34.3  325   4  2  10.8   5.9 |   1.9  35.4  355   5  3  11.2   6.1
  6250   2.1  35.8  325   4  2  10.6   5.8 |   2.6  36.7  350   5  3   9.5   5.2
  6000   2.9  37.2  325   4  2   9.9   5.5 |   3.4  38.1  350   5  3   9.6   5.2
  5750   3.7  38.7  320   4  2  12.5   6.8 |   4.1  39.4  345   5  3   9.6   5.3
  5500   4.8  40.6  325   4  2  19.1  10.5 |   4.8  40.6  345   5  2  11.4   6.3
________________________________________________________________________________

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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