Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 231352
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0651 MST Tuesday, January 23, 2018

This forecast is for Tuesday, January 23, 2018:

If the trigger temperature of 30.5 F/-0.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 764 ft/min (3.9 m/s)
   Maximum height of thermals.................. 16463 ft MSL (8857 ft AGL)

Forecast maximum temperature................... 41.0 F/5.5 C
Time of trigger temperature.................... 1000 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14536 ft MSL (6930 ft AGL)
Thermal soaring outlook for Wednesday 01/24.... Excellent

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 07:12:23 / 17:10:00 MST
Total possible sunshine........... 9 hr 57 min 37 sec (597 min 37 sec)
Altitude of sun at 12:11:11 MST... 31.64 degrees

Upper air data from numerical model forecast valid on 01/23/2018 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 16893 ft MSL (9287 ft AGL)
Lifted condensation level....... 16807 ft MSL (9202 ft AGL)
Lifted index.................... +1.4
K index......................... +2.3

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   285   21   11   0.9   0.5      M     M       M      M    M
 45000  -54.1 -65.4   290   25   13   0.9   0.5      M     M       M      M    M
 40000  -53.0 -63.4   285   31   16   0.7   0.4      M     M       M      M    M
 38000  -52.6 -62.7   285   33   17  -0.3  -0.2      M     M       M      M    M
 36000  -52.8 -63.0   285   32   16  -0.4  -0.2      M     M       M      M    M
 34000  -53.1 -63.6   280   31   16  -0.3  -0.2      M     M       M      M    M
 32000  -53.4 -64.1   280   29   15  -0.5  -0.3      M     M       M      M    M
 30000  -53.7 -64.7   280   26   13  -1.4  -0.8      M     M       M      M    M
 29000  -52.3 -62.1   280   26   13   6.8   3.8   12.9  55.3     6.1      M    M
 28000  -50.2 -58.4   285   26   13   6.8   3.7   11.7  53.1     5.3      M    M
 27000  -48.2 -54.8   285   26   13   6.8   3.7   10.7  51.2     4.5      M    M
 26000  -45.9 -50.6   290   25   13   8.9   4.9    9.9  49.8     3.9      M    M
 25000  -43.3 -45.9   290   25   13   8.8   4.8    9.5  49.0     3.6      M    M
 24000  -40.7 -41.3   290   24   12   8.8   4.8    9.2  48.5     3.4      M    M
 23000  -38.0 -36.4   295   23   12   9.2   5.0    8.9  48.0     3.2      M    M
 22000  -35.3 -31.5   295   23   12   9.2   5.0    8.6  47.5     3.0      M    M
 21000  -32.5 -26.5   300   22   11   9.2   5.0    8.5  47.2     2.9      M    M
 20000  -29.3 -20.7   300   20   10   8.6   4.7    8.0  46.4     2.6      M    M
 19500  -28.0 -18.4   300   19   10   8.6   4.7    7.8  46.0     2.4      M    M
 19000  -26.7 -16.1   300   18    9   8.5   4.7    7.6  45.7     2.3      M    M
 18500  -25.4 -13.7   300   17    9   8.3   4.5    7.4  45.4     2.1      M    M
 18000  -24.4 -11.9   300   16    8   6.4   3.5    7.0  44.6     1.7      M    M
 17500  -23.4 -10.1   300   15    8   6.7   3.7    6.5  43.6     1.2      M    M
 17000  -22.5  -8.5   300   14    7   5.2   2.9    5.9  42.5     0.7      M    M
 16500  -21.8  -7.2   300   13    7   5.2   2.8    5.1  41.2    -0.0    763  3.9
 16000  -21.0  -5.8   295   12    6   4.8   2.6    4.3  39.8    -0.7    726  3.7
 15500  -20.3  -4.5   295   11    6   4.6   2.5    3.5  38.2    -1.5    691  3.5
 15000  -19.7  -3.5   295   10    5   4.7   2.6    2.6  36.7    -2.3    656  3.3
 14500  -18.9  -2.0   295   10    5   5.1   2.8    1.8  35.3    -3.1    620  3.1
 14000  -18.2  -0.8   290    9    5   5.4   2.9    1.1  34.0    -3.8    582  3.0
 13500  -17.3   0.9   295    9    5   6.8   3.7    0.5  33.0    -4.4    540  2.7
 13000  -16.3   2.7   295    9    5   6.9   3.8    0.1  32.1    -4.8    495  2.5
 12500  -15.1   4.8   300   10    5   8.7   4.8   -0.2  31.6    -5.1    444  2.3
 12000  -13.8   7.2   300    9    5   8.4   4.6   -0.4  31.3    -5.4    392  2.0
 11750  -13.2   8.2   300    9    4   8.3   4.5   -0.5  31.1    -5.5    366  1.9
 11500  -12.6   9.3   300    9    4   8.2   4.5   -0.6  30.8    -5.6    341  1.7
 11250  -12.0  10.4   305    8    4   9.3   5.1   -0.7  30.7    -5.7    314  1.6
 11000  -11.2  11.8   305    8    4   9.4   5.2   -0.7  30.7    -5.8    285  1.4
 10750  -10.6  12.9   310    8    4   8.4   4.6   -0.8  30.5    -5.8    258  1.3
 10500  -10.0  14.0   310    7    4   7.4   4.1   -0.9  30.3    -6.0    232  1.2
 10250   -9.3  15.3   315    7    4  10.5   5.8   -1.1  30.1    -6.1    206  1.0
 10000   -8.4  16.9   315    7    4  11.5   6.3   -0.9  30.4    -5.9    171  0.9
  9750   -7.7  18.1   315    7    3   8.5   4.7   -0.9  30.4    -6.0    142  0.7
  9500   -7.0  19.4   320    6    3   8.7   4.8   -1.0  30.2    -6.0    115  0.6
  9250   -6.4  20.5   320    6    3   8.7   4.8   -1.1  30.1    -6.1     88  0.4
  9000   -5.8  21.6   320    5    3   6.2   3.4   -1.2  29.8    -6.3     63  0.3
  8750   -5.4  22.3   320    5    3   4.1   2.3   -1.6  29.1    -6.7     45  0.2
  8500   -5.1  22.8   320    5    3   5.3   2.9   -2.0  28.4    -7.1     27  0.1
  8250   -4.8  23.4   320    5    3   2.8   1.5   -2.4  27.8    -7.5     10  0.0
  8000   -5.1  22.8   325    5    3 -14.0  -7.7   -3.4  25.9    -8.5     11  0.1
  7750   -7.0  19.4   315    4    2 -34.3 -18.8   -6.0  21.2   -11.2     61  0.3
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           01/23/2018 at 0800 MST          |       01/23/2018 at 1100 MST
                                           |
CAPE...     0.0    LI...       +4.1        | CAPE...     0.0    LI...       +3.7
CINH...     0.0    K Index... -12.1        | CINH...     0.0    K Index... -17.4
                                           |
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 -57.0 -70.6  285  22 11   1.0   0.6 | -55.8 -68.4  285  20 10   0.2   0.1
 45000 -55.5 -67.9  295  27 14   1.0   0.6 | -55.5 -67.9  290  24 12   0.2   0.1
 40000 -53.8 -64.8  290  34 18   1.1   0.6 | -53.9 -65.0  285  29 15   1.2   0.6
 38000 -53.1 -63.6  285  36 19   1.4   0.8 | -53.2 -63.8  285  31 16   1.3   0.7
 36000 -52.3 -62.1  285  34 17   1.4   0.8 | -52.4 -62.3  285  29 15   1.3   0.7
 34000 -51.4 -60.5  285  31 16   1.4   0.8 | -51.6 -60.9  285  28 14   1.4   0.7
 32000 -51.2 -60.2  285  27 14   0.2   0.1 | -51.1 -60.0  295  24 12   0.8   0.4
 30000 -51.1 -60.0  290  23 12  -0.1  -0.0 | -50.6 -59.1  310  22 11   0.9   0.5
 29000 -50.2 -58.4  290  22 11   4.2   2.3 | -49.4 -56.9  315  22 11   4.7   2.6
 28000 -49.0 -56.2  290  22 11   4.3   2.3 | -48.0 -54.4  320  23 12   4.7   2.6
 27000 -47.7 -53.9  295  21 11   4.2   2.3 | -46.6 -51.9  320  23 12   4.7   2.6
 26000 -46.1 -51.0  295  20 10   8.1   4.4 | -44.9 -48.8  325  23 12   7.3   4.0
 25000 -43.2 -45.8  295  20 10   7.7   4.2 | -42.7 -44.9  320  23 12   7.2   4.0
 24000 -40.9 -41.6  295  20 10   7.7   4.2 | -40.6 -41.1  320  23 12   7.3   4.0
 23000 -38.4 -37.1  295  19 10   8.6   4.7 | -38.2 -36.8  320  22 11   8.4   4.6
 22000 -35.8 -32.4  300  19 10   8.6   4.7 | -35.7 -32.3  320  21 11   8.3   4.6
 21000 -33.3 -27.9  300  19 10   8.7   4.8 | -33.2 -27.8  315  21 11   8.3   4.6
 20000 -30.5 -22.9  300  18  9   9.2   5.1 | -30.7 -23.3  315  20 10   8.7   4.7
 19500 -29.1 -20.4  300  18  9   9.2   5.1 | -28.7 -19.7  315  20 10   8.7   4.7
 19000 -27.7 -17.9  300  18  9   9.2   5.1 | -27.4 -17.3  315  19 10   8.6   4.7
 18500 -26.3 -15.3  305  18  9   9.2   5.0 | -26.1 -15.0  310  19 10   8.4   4.6
 18000 -25.0 -13.0  305  17  9   8.7   4.8 | -24.9 -12.8  310  19 10   7.9   4.3
 17500 -23.7 -10.7  305  17  9   8.9   4.9 | -23.8 -10.8  310  18  9   7.9   4.3
 17000 -22.5  -8.5  305  17  9   7.3   4.0 | -22.6  -8.7  310  17  9   7.9   4.3
 16500 -21.4  -6.5  305  16  8   7.1   3.9 | -21.4  -6.5  305  16  8   7.9   4.4
 16000 -20.3  -4.5  305  15  8   6.3   3.5 | -20.2  -4.4  305  16  8   7.5   4.1
 15500 -19.5  -3.1  300  14  7   5.7   3.1 | -19.1  -2.4  305  14  7   7.4   4.0
 15000 -18.7  -1.7  300  13  7   5.0   2.8 | -18.0  -0.4  300  13  7   6.5   3.5
 14500 -18.1  -0.6  300  12  6   3.4   1.9 | -17.2   1.0  300  12  6   5.7   3.1
 14000 -17.6   0.3  300  10  5   3.8   2.1 | -16.3   2.7  300  11  5   4.8   2.6
 13500 -16.9   1.6  305  10  5   5.6   3.1 | -15.8   3.6  300  10  5   3.4   1.9
 13000 -16.1   3.0  310  10  5   5.7   3.1 | -15.3   4.5  305   9  5   3.8   2.1
 12500 -15.0   5.0  320  10  5   7.4   4.1 | -14.7   5.5  315  10  5   5.5   3.0
 12000 -14.0   6.8  320  10  5   6.5   3.6 | -13.7   7.3  325   9  5   7.0   3.8
 11750 -13.6   7.5  320  10  5   6.6   3.6 | -13.2   8.2  325   9  5   6.9   3.8
 11500 -13.1   8.4  320  10  5   6.6   3.6 | -12.6   9.3  330  10  5   6.6   3.6
 11250 -12.6   9.3  320  11  5   7.1   3.9 | -12.1  10.2  330  10  5   9.8   5.4
 11000 -12.0  10.4  320  10  5   7.6   4.2 | -11.3  11.7  335  10  5   9.5   5.2
 10750 -11.4  11.5  320  10  5   7.7   4.2 | -10.7  12.7  335  10  5   6.8   3.7
 10500 -10.9  12.4  320  10  5   7.2   3.9 | -10.2  13.6  330  10  5   6.5   3.6
 10250 -10.3  13.5  320  10  5   9.2   5.0 |  -9.7  14.5  330  10  5   9.7   5.3
 10000  -9.5  14.9  320   9  5  10.5   5.8 |  -8.9  16.0  330  10  5   9.7   5.3
  9750  -8.8  16.2  320   9  5   8.9   4.9 |  -8.3  17.1  325   9  4   6.2   3.4
  9500  -8.1  17.4  320   8  4   9.7   5.3 |  -7.8  18.0  325   7  4   7.6   4.2
  9250  -7.5  18.5  320   8  4   6.9   3.8 |  -7.3  18.9  320   6  3   5.6   3.1
  9000  -7.1  19.2  320   8  4   5.9   3.2 |  -6.9  19.6  315   6  3   8.0   4.4
  8750  -6.5  20.3  325   7  4   7.5   4.1 |  -6.1  21.0  315   6  3  11.3   6.2
  8500  -6.0  21.2  325   7  4   7.9   4.3 |  -5.3  22.5  315   5  3  10.8   5.9
  8250  -5.4  22.3  325   7  3   4.7   2.6 |  -4.5  23.9  315   5  2   9.2   5.0
  8000  -5.6  21.9  325   6  3 -12.1  -6.6 |  -3.8  25.2  315   5  2  12.3   6.7
  7750  -7.3  18.9  310   5  2 -29.4 -16.1 |  -2.5  27.5  315   4  2  22.8  12.5
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/23/2018 at 1400 MST          |       01/23/2018 at 1700 MST
                                           |
CAPE...     0.0    LI...       +4.0        | CAPE...     0.0    LI...       +3.7
CINH...     0.0    K Index...  -5.9        | CINH...     0.0    K Index...  -6.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -55.8 -68.4  285  19 10   0.6   0.3 | -56.4 -69.5  350 115 59   0.3   0.2
 45000 -54.9 -66.8  280  22 11   0.6   0.4 | -55.9 -68.6  335  54 28   0.4   0.2
 40000 -53.0 -63.4  285  26 13   1.4   0.7 | -53.7 -64.7  340  57 29   1.6   0.9
 38000 -52.2 -62.0  285  27 14   0.2   0.1 | -53.0 -63.4  345  71 37  -1.5  -0.8
 36000 -52.1 -61.8  290  28 14   0.3   0.2 | -53.9 -65.0  355 151 78  -1.3  -0.7
 34000 -51.9 -61.4  290  28 15   0.3   0.1 | -54.7 -66.5  355 223 115  -1.4  -0.7
 32000 -51.7 -61.1  310  25 13   0.4   0.2 | -53.4 -64.1  355 281 145   2.6   1.4
 30000 -51.5 -60.7  330  25 13   0.4   0.2 | -51.8 -61.2  360 337 174   3.7   2.0
 29000 -50.1 -58.2  330  25 13   5.6   3.0 | -49.8 -57.6  360 337 174   7.1   3.9
 28000 -48.4 -55.1  330  25 13   5.5   3.0 | -47.7 -53.9  360 334 172   7.1   3.9
 27000 -46.8 -52.2  330  25 13   5.6   3.1 | -45.6 -50.1  360 332 171   7.1   3.9
 26000 -44.9 -48.8  330  25 13   7.6   4.2 | -43.4 -46.1  360 319 164   7.7   4.2
 25000 -42.6 -44.7  325  26 13   7.6   4.2 | -41.1 -42.0  360 298 154   7.7   4.2
 24000 -40.3 -40.5  325  26 13   7.6   4.2 | -38.8 -37.8  355 277 143   7.7   4.2
 23000 -37.9 -36.2  320  26 13   8.6   4.7 | -36.4 -33.5  355 265 136   8.4   4.6
 22000 -35.3 -31.5  320  25 13   8.6   4.7 | -33.2 -27.8  355 260 134   8.4   4.6
 21000 -32.1 -25.8  320  24 12   8.6   4.7 | -30.7 -23.3  355 256 132   8.2   4.5
 20000 -29.5 -21.1  315  22 11   8.7   4.8 | -28.3 -18.9  355 247 127   8.0   4.4
 19500 -28.2 -18.8  315  21 11   8.7   4.8 | -27.1 -16.8  355 243 125   8.0   4.4
 19000 -26.9 -16.4  315  20 10   8.7   4.8 | -25.9 -14.6  355 238 123   8.0   4.4
 18500 -25.6 -14.1  315  19 10   8.4   4.6 | -24.7 -12.5  355 234 120   7.7   4.3
 18000 -24.4 -11.9  315  20 10   7.9   4.3 | -23.6 -10.5  355 235 121   7.5   4.1
 17500 -23.2  -9.8  315  20 10   8.0   4.4 | -22.5  -8.5  355 235 121   7.5   4.1
 17000 -22.1  -7.8  315  20 10   6.7   3.7 | -21.4  -6.5  355 235 121   7.7   4.2
 16500 -21.1  -6.0  310  20 10   6.8   3.8 | -20.2  -4.4  355 234 120   7.7   4.2
 16000 -20.1  -4.2  305  19 10   5.8   3.2 | -19.1  -2.4  355 233 120   6.6   3.6
 15500 -19.3  -2.7  305  17  9   5.6   3.1 | -18.2  -0.8  355 234 120   6.5   3.5
 15000 -18.5  -1.3  300  16  8   5.1   2.8 | -17.2   1.0  355 234 121   5.8   3.2
 14500 -17.8  -0.0  300  15  8   4.7   2.6 | -16.4   2.5  355 229 118   5.4   2.9
 14000 -17.1   1.2  295  13  7   5.2   2.8 | -15.7   3.7  355 223 115   5.5   3.0
 13500 -16.3   2.7  300  12  6   6.0   3.3 | -14.8   5.4  355 160 83   5.8   3.2
 13000 -15.4   4.3  300  12  6   6.4   3.5 | -14.0   6.8  355  95 49   6.7   3.7
 12500 -14.4   6.1  305  11  5   7.8   4.3 | -12.8   9.0  345  35 18   8.5   4.7
 12000 -13.1   8.4  305   8  4   8.2   4.5 | -11.5  11.3  300  11  5   7.9   4.3
 11750 -12.6   9.3  305   7  4   7.7   4.2 | -11.0  12.2  215  15  8   6.3   3.4
 11500 -12.0  10.4  305   7  3   7.7   4.2 | -10.6  12.9  195  32 17   6.0   3.3
 11250 -11.3  11.7  305   6  3  10.0   5.5 | -10.1  13.8  190  50 25   8.5   4.7
 11000 -10.6  12.9  305   5  3   9.8   5.4 |  -9.4  15.1  185  63 32   7.3   4.0
 10750  -9.9  14.2  305   5  2   8.1   4.5 |  -9.1  15.6  185  85 44   4.1   2.3
 10500  -9.3  15.3  305   4  2   7.7   4.2 |  -8.7  16.3  185 109 56   4.3   2.4
 10250  -8.7  16.3  310   3  2  10.6   5.8 |  -8.4  16.9  180 132 68   5.4   2.9
 10000  -7.8  18.0  315   2  1  11.6   6.3 |  -8.0  17.6  180 156 80   5.6   3.1
  9750  -7.1  19.2  315   2  1   9.1   5.0 |  -7.6  18.3  180 165 85   4.5   2.5
  9500  -6.3  20.7  320   2  1  10.3   5.7 |  -7.2  19.0  180 174 89   5.2   2.8
  9250  -5.6  21.9  325   2  1   7.9   4.3 |  -6.9  19.6  180 182 94   3.8   2.1
  9000  -5.1  22.8  330   2  1   8.5   4.7 |  -6.6  20.1  180 186 96   4.6   2.5
  8750  -4.3  24.3  335   2  1  11.0   6.0 |  -6.2  20.8  180 179 92   6.6   3.6
  8500  -3.5  25.7  340   2  1  10.7   5.9 |  -5.7  21.7  180 172 88   5.9   3.2
  8250  -2.7  27.1  345   1  1   9.4   5.2 |  -5.3  22.5  180 164 85   6.9   3.8
  8000  -2.0  28.4  350   1  1  11.7   6.4 |  -4.9  23.2  180 165 85   2.6   1.4
  7750  -0.8  30.6  355   1  1  20.1  11.0 |  -5.1  22.8  180 154 79  -6.9  -3.8
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 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 Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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.

CIN (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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