Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 241319
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0719 MDT Friday, March 24, 2017

This forecast is for Friday, March 24, 2017:

If the trigger temperature of 47.7 F/8.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 38 ft/min (0.2 m/s)
   Maximum height of thermals.................. 11318 ft MSL (6033 ft AGL)

Forecast maximum temperature................... 53.0 F/12.1 C
Time of trigger temperature.................... 1245 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................. 9178 ft MSL (3892 ft AGL)
Thermal soaring outlook for Saturday 03/25..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 20038 ft MSL (14753 ft AGL)
Wave soaring outlook for Saturday 03/25........ Poor

Remarks...

Sunrise/Sunset.................... 06:55:31 / 19:15:39 MDT
Total possible sunshine........... 12 hr 20 min 8 sec (740 min 8 sec)
Altitude of sun at 13:05:35 MDT... 51.93 degrees

Upper air data from rawinsonde observation taken on 03/24/2017 at 0600 MDT

Freezing level.................. 6218 ft MSL (933 ft AGL)
Convective condensation level... 9896 ft MSL (4611 ft AGL)
Lifted condensation level....... 10744 ft MSL (5458 ft AGL)
Lifted index.................... +4.0
K index......................... +18.4

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  -56.5 -69.7   235   43   22   3.9   2.1  105.4 221.7    53.7      M    M
 45000  -50.7 -59.3   225   29   15   3.9   2.1   90.5 194.9    48.2      M    M
 40000  -48.2 -54.8   250   21   11   0.5   0.3   70.0 158.0    38.2      M    M
 38000  -49.1 -56.4   250   12    6  -0.9  -0.5   59.9 139.9    32.5      M    M
 36000  -50.6 -59.1   110    8    4  -5.6  -3.1   49.2 120.6    25.9      M    M
 34000  -57.5 -71.5   085   38   20   6.8   3.7   31.0  87.8    13.7      M    M
 32000  -52.0 -61.6   080   35   18   9.2   5.0   30.2  86.4    13.5      M    M
 30000  -46.5 -51.7   070   32   16   8.7   4.7   30.0  86.0    13.7      M    M
 29000  -43.4 -46.1   065   32   17   8.4   4.6   29.1  84.4    13.3      M    M
 28000  -40.9 -41.6   055   33   17   8.4   4.6   28.5  83.3    13.0      M    M
 27000  -38.4 -37.1   050   34   17   8.4   4.6   28.1  82.5    12.7      M    M
 26000  -35.9 -32.6   045   35   18   8.4   4.6   27.7  81.9    12.6      M    M
 25000  -33.3 -27.9   040   37   19   8.4   4.6   27.5  81.4    12.5      M    M
 24000  -30.8 -23.4   040   39   20   8.5   4.7   26.9  80.3    12.2      M    M
 23000  -28.4 -19.1   035   40   20   7.9   4.3   26.2  79.2    11.8      M    M
 22000  -26.2 -15.2   025   40   20   7.4   4.0   25.3  77.6    11.2      M    M
 21000  -24.0 -11.2   020   40   21   7.4   4.1   24.5  76.1    10.6      M    M
 20000  -21.8  -7.2   010   42   22   7.4   4.1   23.8  74.8    10.1      M    M
 19500  -20.7  -5.3   010   42   22   7.4   4.1   23.3  74.0     9.8      M    M
 19000  -19.6  -3.3   010   43   22   7.5   4.1   22.9  73.2     9.4      M    M
 18500  -18.7  -1.7   010   43   22   3.6   2.0   22.4  72.3     9.0      M    M
 18000  -18.0  -0.4   010   43   22   6.2   3.4   21.4  70.5     8.2      M    M
 17500  -17.2   1.0   010   43   22   5.7   3.1   20.7  69.2     7.6      M    M
 17000  -16.4   2.5   015   42   22   5.7   3.1   20.0  68.0     7.1      M    M
 16500  -15.5   4.1   015   42   22   5.7   3.1   19.4  66.9     6.5      M    M
 16000  -14.7   5.5   015   42   22   5.7   3.1   18.8  65.8     6.0      M    M
 15500  -13.9   7.0   015   42   22   5.7   3.1   18.1  64.5     5.4      M    M
 15000  -13.0   8.6   015   42   21   5.7   3.1   17.4  63.3     4.8      M    M
 14500  -11.8  10.8   015   41   21   5.7   3.1   16.4  61.5     3.9      M    M
 14000  -10.9  12.4   015   41   21   5.7   3.1   15.8  60.4     3.3      M    M
 13500  -10.1  13.8   015   42   21   5.7   3.1   15.1  59.1     2.7      M    M
 13000   -9.3  15.3   010   42   22   5.7   3.1   14.4  57.9     2.1      M    M
 12500   -8.4  16.9   010   43   22   5.7   3.2   13.7  56.7     1.5      M    M
 12000   -7.6  18.3   010   43   22   5.8   3.2   13.1  55.6     0.8      M    M
 11500   -6.8  19.8   010   43   22   5.8   3.2   12.4  54.3     0.2      M    M
 11000   -5.9  21.4   010   42   22   5.8   3.2   11.7  53.1    -0.5    407  2.1
 10500   -5.1  22.8   015   42   22   5.8   3.2   11.0  51.9    -1.2    367  1.9
 10250   -4.7  23.5   015   42   22   5.9   3.2   10.7  51.3    -1.5    347  1.8
 10000   -4.3  24.3   015   42   22   5.5   3.0   10.4  50.8    -1.8    328  1.7
  9750   -3.9  25.0   015   42   22   4.8   2.7   10.1  50.1    -2.1    309  1.6
  9500   -3.5  25.7   015   42   22   4.7   2.6    9.7  49.4    -2.5    291  1.5
  9250   -3.2  26.2   015   42   22   4.8   2.6    9.3  48.7    -2.9    274  1.4
  9000   -2.9  26.8   015   42   22   4.8   2.6    8.9  48.0    -3.3    256  1.3
  8750   -2.5  27.5   010   42   22   4.7   2.6    8.5  47.3    -3.7    239  1.2
  8500   -2.2  28.0   010   43   22   4.9   2.7    8.1  46.6    -4.1    221  1.1
  8250   -1.8  28.8   005   43   22   4.3   2.3    7.7  45.9    -4.5    203  1.0
  8000   -1.6  29.1   005   44   23   3.1   1.7    7.3  45.1    -5.0    188  1.0
  7750   -1.3  29.7   005   45   23   2.9   1.6    6.7  44.1    -5.5    174  0.9
  7500   -1.1  30.0   360   45   23   2.9   1.6    6.2  43.1    -6.1    160  0.8
  7250   -0.9  30.4   360   46   24   2.9   1.6    5.7  42.2    -6.6    146  0.7
  7000   -0.7  30.7   360   47   24   2.9   1.6    5.2  41.3    -7.1    132  0.7
  6750   -0.5  31.1   355   43   22   2.8   1.6    4.6  40.3    -7.6    119  0.6
  6500   -0.3  31.5   355   40   21   3.2   1.7    4.1  39.4    -8.2    105  0.5
  6250   -0.0  32.0   350   36   19   2.0   1.1    3.6  38.5    -8.7     91  0.5
  6000    0.2  32.4   345   33   17   6.5   3.5    3.1  37.5    -9.2     77  0.4
  5750    0.9  33.6   340   28   15  12.7   7.0    3.1  37.7    -9.2     47  0.2
  5500    1.8  35.2   335   23   12   9.6   5.3    3.3  37.9    -9.2     14  0.1

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

           03/24/2017 at 0900 MDT          |       03/24/2017 at 1200 MDT
                                           |
CAPE...    +9.2    LI...       +6.3        | CAPE...   +31.0    LI...       +5.9
CINH...    -1.4    K Index... +14.4        | CINH...    -2.1    K Index... +10.8
                                           |
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 -56.1 -69.0  190  84 43   3.6   2.0 | -57.1 -70.8  195  49 25   3.0   1.6
 45000 -50.6 -59.1  190  61 31   2.6   1.4 | -52.6 -62.7  195  37 19   2.1   1.1
 40000 -50.2 -58.4  355 100 51   0.2   0.1 | -51.9 -61.4  355  80 41   0.4   0.2
 38000 -50.8 -59.4  355 135 70  -2.3  -1.3 | -52.5 -62.5  355 104 54  -2.3  -1.2
 36000 -52.2 -62.0  360 121 62  -2.3  -1.3 | -53.8 -64.8  355 106 55  -2.3  -1.2
 34000 -53.3 -63.9  360 105 54   3.6   1.9 | -54.6 -66.3  355 103 53   6.8   3.7
 32000 -50.6 -59.1  005  61 31   4.5   2.5 | -50.8 -59.4  360  51 26   6.4   3.5
 30000 -47.6 -53.7  020  22 11   8.9   4.9 | -46.8 -52.2  010   8  4   9.1   5.0
 29000 -44.9 -48.8  020  23 12   9.0   4.9 | -44.1 -47.4  005  10  5   8.9   4.9
 28000 -42.3 -44.1  020  23 12   9.0   4.9 | -41.4 -42.5  360  12  6   8.9   4.9
 27000 -39.6 -39.3  020  24 12   9.0   4.9 | -38.8 -37.8  355  15  8   8.9   4.9
 26000 -36.9 -34.4  015  23 12   9.0   4.9 | -36.1 -33.0  355  14  7   8.7   4.8
 25000 -34.2 -29.6  015  21 11   9.0   4.9 | -33.5 -28.3  350  13  7   8.7   4.8
 24000 -31.5 -24.7  015  20 10   9.1   5.0 | -30.9 -23.6  350  12  6   8.8   4.8
 23000 -29.0 -20.2  015  17  9   8.0   4.4 | -28.4 -19.1  355  12  6   7.9   4.4
 22000 -26.6 -15.9  015  14  7   8.0   4.4 | -26.0 -14.8  360  12  6   8.0   4.4
 21000 -24.2 -11.6  015  11  6   8.0   4.4 | -23.1  -9.6  010  13  6   7.1   3.9
 20000 -21.5  -6.7  015  10  5   7.3   4.0 | -21.0  -5.8  015  14  7   7.1   3.9
 19500 -20.4  -4.7  015  10  5   7.3   4.0 | -19.9  -3.8  015  15  8   7.1   3.9
 19000 -19.3  -2.7  015  10  5   7.3   4.0 | -18.9  -2.0  015  16  8   7.1   3.9
 18500 -18.2  -0.8  015  10  5   7.0   3.8 | -17.9  -0.2  015  16  8   6.3   3.5
 18000 -17.2   1.0  020  11  6   6.6   3.6 | -17.0   1.4  015  16  8   6.1   3.3
 17500 -16.3   2.7  020  12  6   6.6   3.6 | -16.1   3.0  015  16  8   6.0   3.3
 17000 -15.3   4.5  020  13  6   6.0   3.3 | -15.3   4.5  015  16  8   5.1   2.8
 16500 -14.5   5.9  020  13  7   6.1   3.4 | -14.6   5.7  015  15  8   5.2   2.9
 16000 -13.6   7.5  020  14  7   4.7   2.6 | -13.9   7.0  010  15  8   4.2   2.3
 15500 -13.0   8.6  020  14  7   4.2   2.3 | -13.2   8.2  010  15  8   4.2   2.3
 15000 -12.4   9.7  015  14  7   3.5   1.9 | -12.6   9.3  010  15  8   3.8   2.1
 14500 -12.0  10.4  015  13  7   2.7   1.5 | -12.1  10.2  010  16  8   3.7   2.0
 14000 -11.6  11.1  015  13  7   2.7   1.5 | -11.6  11.1  010  16  8   3.8   2.1
 13500 -11.2  11.8  010  12  6   3.1   1.7 | -11.1  12.0  010  17  9   3.8   2.1
 13000 -10.7  12.7  010  12  6   3.2   1.8 | -10.5  13.1  010  18  9   3.7   2.0
 12500 -10.2  13.6  010  12  6   4.1   2.2 | -10.0  14.0  010  18  9   3.4   1.9
 12000  -9.6  14.7  010  13  6   4.3   2.3 |  -9.5  14.9  010  17  9   4.1   2.3
 11500  -8.8  16.2  360  56 29   6.4   3.5 |  -8.7  16.3  010  17  9   5.6   3.1
 11000  -7.9  17.8  360 117 60   6.1   3.4 |  -7.9  17.8  005  16  8   6.1   3.3
 10500  -7.1  19.2  360 132 68   5.3   2.9 |  -6.9  19.6  005  15  8   6.9   3.8
 10250  -6.7  19.9  360 131 68   5.3   2.9 |  -6.4  20.5  005  15  8   6.9   3.8
 10000  -6.3  20.7  360 131 67   5.6   3.1 |  -5.9  21.4  005  14  7   7.6   4.2
  9750  -5.9  21.4  360 131 67   5.3   2.9 |  -5.3  22.5  005  14  7   8.1   4.4
  9500  -5.5  22.1  360 130 67   4.7   2.6 |  -4.8  23.4  360  13  7   7.8   4.3
  9250  -5.2  22.6  360 130 67   5.0   2.7 |  -4.2  24.4  360  13  7   8.0   4.4
  9000  -4.8  23.4  360 130 67   4.4   2.4 |  -3.6  25.5  360  13  6   8.4   4.6
  8750  -4.5  23.9  360 129 67   5.7   3.1 |  -3.0  26.6  360  29 15   8.8   4.8
  8500  -4.0  24.8  360 129 66   7.0   3.8 |  -2.3  27.9  360  76 39   8.8   4.8
  8250  -3.5  25.7  360 128 66   6.7   3.7 |  -1.7  28.9  360 123 63   9.1   5.0
  8000  -3.0  26.6  360 128 66   6.9   3.8 |  -1.0  30.2  360 130 67   9.6   5.2
  7750  -2.5  27.5  360 129 67   7.2   4.0 |  -0.3  31.5  360 129 67   9.0   5.0
  7500  -2.0  28.4  360 189 97   7.4   4.0 |   0.4  32.7  360 129 67   8.9   4.9
  7250  -1.4  29.5  360 245 126   7.9   4.3 |   1.1  34.0  360 129 66   9.9   5.4
  7000  -0.8  30.6  360 244 126   8.5   4.7 |   1.9  35.4  360 129 66  11.0   6.0
  6750  -0.2  31.6  360 243 125   8.4   4.6 |   2.7  36.9  360 129 66   8.8   4.8
  6500   0.4  32.7  360 242 125   8.9   4.9 |   3.3  37.9  360 128 66   8.8   4.8
  6250   1.1  34.0  360 241 124   9.3   5.1 |   4.0  39.2  360 128 66  10.9   6.0
  6000   1.8  35.2  360 240 124   9.5   5.2 |   4.8  40.6  360 128 66  10.3   5.7
  5750   2.5  36.5  360 239 123   8.7   4.8 |   5.6  42.1  360 127 65  11.0   6.0
  5500   3.1  37.6  360 238 123   7.5   4.1 |   6.5  43.7  360 126 65  14.5   8.0

           03/24/2017 at 1500 MDT          |       03/24/2017 at 1800 MDT
                                           |
CAPE...   +37.9    LI...       +4.2        | CAPE...   +12.1    LI...       +4.5
CINH...    -1.7    K Index... +12.2        | CINH...    -5.8    K Index...  -0.5
                                           |
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  200  35 18   3.1   1.7 | -58.4 -73.1  205  27 14   1.8   1.0
 45000 -52.1 -61.8  220  17  9   1.9   1.0 | -55.6 -68.1  340  31 16   0.4   0.2
 40000 -54.0 -65.2  355  87 45  -1.3  -0.7 | -57.4 -71.3  355 160 82  -1.2  -0.7
 38000 -54.6 -66.3  355 112 58  -0.5  -0.3 | -56.9 -70.4  355 198 102   3.3   1.8
 36000 -54.9 -66.8  355 122 63  -0.5  -0.3 | -54.6 -66.3  360 221 114   3.3   1.8
 34000 -54.7 -66.5  360 131 67   7.1   3.9 | -52.3 -62.1  360 226 116   6.4   3.5
 32000 -50.6 -59.1  360 122 63   6.9   3.8 | -48.4 -55.1  360 172 89   6.3   3.5
 30000 -46.3 -51.3  355 114 59   8.7   4.8 | -44.4 -47.9  360 147 75   7.8   4.3
 29000 -43.2 -45.8  360 114 59   8.4   4.6 | -42.1 -43.8  360 180 93   7.9   4.3
 28000 -40.7 -41.3  360 115 59   8.4   4.6 | -39.7 -39.5  360 214 110   7.9   4.3
 27000 -38.2 -36.8  360 114 59   8.0   4.4 | -37.3 -35.1  360 247 127   7.7   4.2
 26000 -35.9 -32.6  355  81 41   7.7   4.2 | -35.1 -31.2  360 244 126   7.5   4.1
 25000 -33.6 -28.5  355  47 24   7.7   4.2 | -32.8 -27.0  360 241 124   7.5   4.1
 24000 -31.3 -24.3  350  13  7   7.8   4.3 | -30.5 -22.9  360 237 122   7.6   4.2
 23000 -28.9 -20.0  355  10  5   8.2   4.5 | -28.2 -18.8  360 235 121   7.9   4.3
 22000 -26.5 -15.7  355  11  6   8.2   4.5 | -25.8 -14.4  360 234 120   7.9   4.3
 21000 -24.0 -11.2  360  15  8   8.1   4.4 | -23.5 -10.3  360 232 119   7.7   4.2
 20000 -21.7  -7.1  360  60 31   8.0   4.4 | -20.6  -5.1  360 233 120   7.6   4.1
 19500 -20.5  -4.9  360  83 43   8.0   4.4 | -19.5  -3.1  360 234 120   7.6   4.2
 19000 -19.3  -2.7  360 105 54   8.0   4.4 | -18.4  -1.1  360 234 121   7.7   4.2
 18500 -18.1  -0.6  360 128 66   7.4   4.1 | -17.3   0.9  360 235 121   6.7   3.7
 18000 -17.1   1.2  360 128 66   6.9   3.8 | -16.3   2.7  360 235 121   6.7   3.7
 17500 -16.2   2.8  360 127 65   6.9   3.8 | -15.3   4.5  360 236 121   6.2   3.4
 17000 -15.2   4.6  360 127 66   6.0   3.3 | -14.5   5.9  360 235 121   5.8   3.2
 16500 -14.3   6.3  360 128 66   6.1   3.4 | -13.6   7.5  360 235 121   5.7   3.1
 16000 -13.5   7.7  360 129 66   4.8   2.6 | -12.8   9.0  360 233 120   4.7   2.6
 15500 -12.8   9.0  360 129 67   4.4   2.4 | -12.1  10.2  360 232 119   4.8   2.6
 15000 -11.9  10.6  360 130 67   3.8   2.1 | -11.5  11.3  360 229 118   3.9   2.2
 14500 -11.3  11.7  360 131 67   3.9   2.1 | -10.9  12.4  360 226 116   4.0   2.2
 14000 -10.8  12.6  360 131 67   4.0   2.2 | -10.3  13.5  360 222 115   4.3   2.4
 13500 -10.2  13.6  360 131 67   4.0   2.2 |  -9.7  14.5  360 218 112   4.4   2.4
 13000  -9.6  14.7  360 131 67   5.0   2.7 |  -9.1  15.6  360 215 111   5.5   3.0
 12500  -8.9  16.0  360 131 67   5.3   2.9 |  -8.2  17.2  360 219 113   6.0   3.3
 12000  -8.1  17.4  360 123 63   6.6   3.6 |  -7.3  18.9  360 223 115   6.9   3.8
 11500  -7.0  19.4  360  62 32   7.2   4.0 |  -6.2  20.8  360 231 119   7.4   4.0
 11000  -6.0  21.2  360  11  6   8.5   4.7 |  -5.2  22.6  360 224 115   8.0   4.4
 10500  -4.7  23.5  360  11  6   9.9   5.4 |  -3.9  25.0  360 103 53   8.1   4.4
 10250  -4.1  24.6  360  11  5   5.4   3.0 |  -3.3  26.1  360  42 22   9.4   5.1
 10000  -3.8  25.2  355  10  5   6.7   3.7 |  -2.6  27.3  360 124 64   9.5   5.2
  9750  -3.0  26.6  360  10  5  12.0   6.6 |  -2.0  28.4  360  91 47   8.4   4.6
  9500  -2.2  28.0  360  11  5  11.4   6.3 |  -1.3  29.7  360  56 29   8.7   4.8
  9250  -1.4  29.5  360  11  6   8.8   4.8 |  -0.7  30.7  005  22 11   8.5   4.7
  9000  -1.0  30.2  360  10  5   6.8   3.7 |  -0.1  31.8  010  12  6   8.6   4.7
  8750  -0.3  31.5  360  10  5  10.7   5.9 |   0.6  33.1  010  13  7   9.1   5.0
  8500   0.5  32.9  360  11  6  11.9   6.5 |   1.3  34.3  010  15  8   9.1   5.0
  8250   1.3  34.3  360  11  6  10.3   5.6 |   2.0  35.6  010  17  9   9.4   5.1
  8000   2.0  35.6  360  11  6   9.4   5.1 |   2.7  36.9  010  19 10   9.6   5.3
  7750   2.7  36.9  360  11  6  10.2   5.6 |   3.3  37.9  010  20 10   8.7   4.8
  7500   3.5  38.3  360  11  6  10.6   5.8 |   4.0  39.2  010  21 11   8.5   4.7
  7250   4.3  39.7  360  12  6  10.5   5.7 |   4.6  40.3  010  20 11   9.2   5.0
  7000   5.0  41.0  005  12  6  10.7   5.9 |   5.3  41.5  010  20 10   9.5   5.2
  6750   5.8  42.4  005  12  6   9.6   5.3 |   6.0  42.8  010  19 10   8.6   4.7
  6500   6.5  43.7  005  12  6   9.7   5.3 |   6.6  43.9  010  21 11   8.5   4.7
  6250   7.2  45.0  005  12  6  11.0   6.1 |   7.3  45.1  010  18  9   9.2   5.1
  6000   8.0  46.4  005  13  7  10.2   5.6 |   7.9  46.2  015  15  8   9.0   5.0
  5750   8.8  47.8  005  13  7  12.1   6.7 |   8.6  47.5  015  12  6   9.2   5.0
  5500   9.8  49.6  360  12  6  17.9   9.8 |   9.3  48.7  010  14  7   9.9   5.4
________________________________________________________________________________

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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