Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 221342
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0642 MST Monday, January 22, 2018

This forecast is for Monday, January 22, 2018:

If the trigger temperature of 25.2 F/-3.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1060 ft/min (5.4 m/s)
   Maximum height of thermals.................. 19733 ft MSL (12134 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 C
Time of trigger temperature.................... 0930 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................. 16523 ft MSL (8924 ft AGL)
Thermal soaring outlook for Tuesday 01/23...... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:13:00 / 17:08:52 MST
Total possible sunshine........... 9 hr 55 min 52 sec (595 min 52 sec)
Altitude of sun at 12:10:56 MST... 31.41 degrees

Upper air data from numerical model forecast valid on 01/22/2018 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 13904 ft MSL (6305 ft AGL)
Lifted condensation level....... 16418 ft MSL (8819 ft AGL)
Lifted index.................... +1.4
K index......................... -6.3

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  -52.7 -62.9   265   11    6   1.6   0.9      M     M       M      M    M
 45000  -50.3 -58.5   270   11    5   1.6   0.9      M     M       M      M    M
 40000  -50.8 -59.4   295   15    7  -0.8  -0.4      M     M       M      M    M
 38000  -51.3 -60.3   300   17    9  -1.5  -0.8      M     M       M      M    M
 36000  -52.6 -62.7   310   17    9  -2.1  -1.1      M     M       M      M    M
 34000  -53.8 -64.8   320   19   10  -2.1  -1.2      M     M       M      M    M
 32000  -53.5 -64.3   320   19   10   2.0   1.1      M     M       M      M    M
 30000  -52.3 -62.1   320   19   10   2.0   1.1      M     M       M      M    M
 29000  -51.3 -60.3   320   18    9   6.5   3.5   15.1  59.1     7.3      M    M
 28000  -49.4 -56.9   320   17    9   6.2   3.4   13.6  56.5     6.3      M    M
 27000  -47.5 -53.5   320   16    8   6.2   3.4   12.3  54.1     5.3      M    M
 26000  -45.6 -50.1   315   15    7   7.1   3.9   11.1  52.0     4.4      M    M
 25000  -43.3 -45.9   320   15    8   7.9   4.3   10.3  50.5     3.8      M    M
 24000  -40.9 -41.6   325   15    8   7.9   4.3    9.6  49.2     3.3      M    M
 23000  -38.0 -36.4   325   16    8   7.1   3.9    8.7  47.7     2.6      M    M
 22000  -35.8 -32.4   335   17    9   7.2   4.0    7.8  46.0     1.9      M    M
 21000  -33.7 -28.7   335   19   10   7.2   3.9    6.9  44.4     1.2      M    M
 20000  -31.7 -25.1   340   21   11   6.2   3.4    5.8  42.5     0.2      M    M
 19500  -30.7 -23.3   345   22   11   6.2   3.4    5.2  41.3    -0.3   1035  5.3
 19000  -29.8 -21.6   345   23   12   6.2   3.4    4.6  40.2    -0.9    992  5.0
 18500  -28.9 -20.0   345   24   12   6.2   3.4    4.0  39.2    -1.4    949  4.8
 18000  -27.9 -18.2   345   24   13   6.9   3.8    3.5  38.2    -1.9    906  4.6
 17500  -26.9 -16.4   350   25   13   7.3   4.0    3.0  37.5    -2.3    859  4.4
 17000  -25.8 -14.4   350   25   13   7.3   4.0    2.6  36.7    -2.7    811  4.1
 16500  -24.6 -12.3   350   25   13   7.6   4.2    2.2  36.0    -3.0    763  3.9
 16000  -23.5 -10.3   350   25   13   7.7   4.2    1.9  35.4    -3.4    714  3.6
 15500  -22.5  -8.5   350   25   13   6.3   3.5    1.4  34.6    -3.8    668  3.4
 15000  -21.5  -6.7   350   25   13   6.5   3.6    0.9  33.6    -4.4    624  3.2
 14500  -20.6  -5.1   350   25   13   5.7   3.1    0.3  32.6    -4.9    582  3.0
 14000  -19.7  -3.5   350   25   13   5.7   3.1   -0.4  31.3    -5.6    542  2.8
 13500  -19.0  -2.2   350   25   13   4.6   2.5   -1.1  30.1    -6.3    503  2.6
 13000  -18.3  -0.9   350   25   13   4.2   2.3   -1.9  28.5    -7.2    469  2.4
 12500  -17.6   0.3   345   25   13   6.8   3.7   -2.6  27.2    -7.9    432  2.2
 12000  -16.6   2.1   345   24   12   6.0   3.3   -3.2  26.3    -8.5    388  2.0
 11750  -16.1   3.0   345   24   12   6.8   3.7   -3.4  25.8    -8.8    367  1.9
 11500  -15.6   3.9   345   23   12   8.8   4.8   -3.6  25.5    -9.0    343  1.7
 11250  -14.9   5.2   345   23   12   8.7   4.8   -3.6  25.4    -9.0    315  1.6
 11000  -14.3   6.3   345   23   12   7.8   4.3   -3.8  25.2    -9.2    290  1.5
 10750  -13.7   7.3   345   22   11   7.8   4.3   -3.9  24.9    -9.4    265  1.3
 10500  -13.2   8.2   345   21   11   7.0   3.8   -4.1  24.6    -9.6    241  1.2
 10250  -12.7   9.1   340   20   10   7.7   4.2   -4.3  24.2    -9.8    218  1.1
 10000  -12.0  10.4   340   19   10   9.3   5.1   -4.4  24.1    -9.9    191  1.0
  9750  -11.3  11.7   340   17    9   9.2   5.1   -4.4  24.0   -10.0    162  0.8
  9500  -10.6  12.9   335   17    9   8.8   4.8   -4.5  23.9   -10.1    135  0.7
  9250   -9.9  14.2   335   16    8   9.0   4.9   -4.6  23.8   -10.2    107  0.5
  9000   -9.3  15.3   335   15    8   7.8   4.3   -4.6  23.7   -10.3     80  0.4
  8750   -8.8  16.2   330   14    7   4.8   2.6   -4.9  23.2   -10.6     58  0.3
  8500   -8.5  16.7   330   13    7   3.1   1.7   -5.4  22.3   -11.0     43  0.2
  8250   -8.2  17.2   325   12    6   5.1   2.8   -5.8  21.5   -11.5     27  0.1
  8000   -7.9  17.8   325   12    6   2.8   1.5   -6.2  20.9   -11.9      8  0.0
  7750   -8.0  17.6   320    8    4  -6.9  -3.8   -7.1  19.3   -12.8      5  0.0
  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 * * * * * *

           01/22/2018 at 0800 MST          |       01/22/2018 at 1100 MST
                                           |
CAPE...     0.0    LI...       +2.4        | CAPE...     0.0    LI...       +2.7
CINH...     0.0    K Index... -35.2        | CINH...     0.0    K Index... -28.2
                                           |
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 -52.7 -62.9  275  12  6   1.0   0.6 | -53.1 -63.6  340  35 18   1.0   0.6
 45000 -51.2 -60.2  270  15  8   1.0   0.6 | -51.4 -60.5  350 105 54   1.1   0.6
 40000 -53.1 -63.6  295  19 10  -1.7  -0.9 | -54.1 -65.4  355 149 77  -2.3  -1.3
 38000 -54.1 -65.4  305  22 11  -1.6  -0.9 | -55.5 -67.9  355 165 85  -1.8  -1.0
 36000 -55.0 -67.0  315  23 12  -1.6  -0.9 | -56.4 -69.5  355 182 94  -1.4  -0.8
 34000 -56.0 -68.8  325  24 12  -1.6  -0.9 | -57.3 -71.1  355 202 104  -1.6  -0.9
 32000 -54.4 -65.9  330  27 14   4.7   2.6 | -55.0 -67.0  355 230 118   5.3   2.9
 30000 -51.6 -60.9  335  30 15   4.8   2.6 | -51.9 -61.4  355 261 134   5.0   2.8
 29000 -50.0 -58.0  335  30 15   6.0   3.3 | -49.9 -57.8  355 272 140   7.3   4.0
 28000 -48.1 -54.6  335  29 15   6.0   3.3 | -47.7 -53.9  355 282 145   7.3   4.0
 27000 -46.3 -51.3  335  27 14   6.0   3.3 | -45.5 -49.9  355 292 150   7.3   4.0
 26000 -44.5 -48.1  335  26 13   6.1   3.3 | -43.3 -45.9  355 301 155   7.6   4.2
 25000 -42.2 -44.0  335  23 12   6.1   3.4 | -41.0 -41.8  360 309 159   7.6   4.2
 24000 -40.4 -40.7  335  21 11   6.1   3.4 | -38.7 -37.7  360 317 163   7.6   4.2
 23000 -38.4 -37.1  335  19 10   7.7   4.2 | -36.5 -33.7  360 325 167   6.7   3.7
 22000 -36.1 -33.0  330  17  9   7.6   4.2 | -34.5 -30.1  360 330 170   6.8   3.7
 21000 -33.8 -28.8  325  15  8   7.6   4.2 | -32.4 -26.3  360 336 173   6.8   3.7
 20000 -31.6 -24.9  330  16  8   7.2   3.9 | -30.1 -22.2  360 341 176   5.8   3.2
 19500 -30.6 -23.1  335  18  9   7.2   3.9 | -29.2 -20.6  360 343 177   5.9   3.2
 19000 -29.5 -21.1  335  19 10   7.2   3.9 | -28.4 -19.1  360 345 177   5.9   3.2
 18500 -28.4 -19.1  340  20 10   7.2   3.9 | -27.5 -17.5  360 347 178   5.8   3.2
 18000 -27.3 -17.1  345  22 11   7.1   3.9 | -26.5 -15.7  360 348 179   7.2   3.9
 17500 -26.3 -15.3  345  22 12   7.1   3.9 | -25.5 -13.9  360 349 180   7.0   3.9
 17000 -25.2 -13.4  350  23 12   7.3   4.0 | -24.4 -11.9  360 350 180   7.4   4.0
 16500 -24.1 -11.4  350  24 12   7.6   4.1 | -23.3  -9.9  360 349 180   7.5   4.1
 16000 -22.9  -9.2  350  25 13   7.6   4.2 | -22.2  -8.0  360 349 180   7.6   4.2
 15500 -21.7  -7.1  355  25 13   8.3   4.6 | -21.0  -5.8  360 349 180   7.9   4.3
 15000 -20.5  -4.9  355  26 13   8.3   4.5 | -19.8  -3.6  360 349 179   8.0   4.4
 14500 -19.3  -2.7  355  26 13   8.2   4.5 | -18.6  -1.5  360 347 179   8.5   4.7
 14000 -18.0  -0.4  355  26 13   8.3   4.5 | -17.3   0.9  360 345 178   8.5   4.6
 13500 -16.9   1.6  355  26 13   7.2   3.9 | -16.1   3.0  360 341 176   7.8   4.3
 13000 -15.8   3.6  355  25 13   6.9   3.8 | -14.9   5.2  360 336 173   7.8   4.3
 12500 -14.6   5.7  355  25 13   7.1   3.9 | -13.7   7.3  360 333 171   7.7   4.2
 12000 -13.9   7.0  350  24 13   4.6   2.5 | -12.7   9.1  360 326 168   6.5   3.6
 11750 -13.5   7.7  350  24 12   4.8   2.6 | -12.2  10.0  360 323 166   7.0   3.8
 11500 -13.2   8.2  350  24 12   5.2   2.8 | -11.7  10.9  360 321 165   7.4   4.1
 11250 -12.8   9.0  350  24 12   5.1   2.8 | -11.1  12.0  360 319 164   6.5   3.6
 11000 -12.4   9.7  350  23 12   5.1   2.8 | -10.7  12.7  360 319 164   6.2   3.4
 10750 -12.0  10.4  350  23 12   5.0   2.7 | -10.2  13.6  360 319 164   6.6   3.6
 10500 -11.7  10.9  350  23 12   4.4   2.4 |  -9.7  14.5  360 320 165   6.3   3.5
 10250 -11.4  11.5  345  23 12   5.6   3.1 |  -9.2  15.4  360 321 165   7.8   4.3
 10000 -10.9  12.4  345  22 12   7.7   4.2 |  -8.6  16.5  360 320 165   9.4   5.2
  9750 -10.3  13.5  345  22 11   8.6   4.7 |  -7.9  17.8  360 317 163   8.6   4.7
  9500  -9.6  14.7  345  22 11   8.8   4.8 |  -7.3  18.9  360 310 160   8.1   4.4
  9250  -8.9  16.0  345  21 11   8.7   4.8 |  -6.7  19.9  360 304 156   8.7   4.8
  9000  -8.4  16.9  340  21 11   5.1   2.8 |  -6.0  21.2  360 296 152   9.8   5.4
  8750  -8.2  17.2  340  20 10   2.8   1.5 |  -5.3  22.5  360 284 146  10.1   5.5
  8500  -8.0  17.6  335  19 10   0.8   0.4 |  -4.5  23.9  360 272 140   9.7   5.3
  8250  -7.8  18.0  330  18  9   9.0   5.0 |  -3.8  25.2  360 260 134  10.4   5.7
  8000  -6.9  19.6  330  17  9   5.7   3.1 |  -2.9  26.8  360 252 130  14.8   8.1
  7750  -7.6  18.3  320  13  7 -24.2 -13.3 |  -1.6  29.1  360 240 123  20.0  11.0
  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

           01/22/2018 at 1400 MST          |       01/22/2018 at 1700 MST
                                           |
CAPE...     0.0    LI...       +3.2        | CAPE...     0.0    LI...       +3.0
CINH...     0.0    K Index... -20.3        | CINH...     0.0    K Index... -18.0
                                           |
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 -53.2 -63.8  345  48 25   0.9   0.5 | -53.6 -64.5  345  53 27   0.6   0.3
 45000 -51.8 -61.2  350 106 55   0.9   0.5 | -52.7 -62.9  350 116 60   0.6   0.3
 40000 -54.6 -66.3  355 119 61  -2.4  -1.3 | -54.9 -66.8  350  97 50  -1.9  -1.0
 38000 -56.0 -68.8  355 122 63  -1.9  -1.0 | -56.1 -69.0  350  85 44  -1.9  -1.1
 36000 -57.0 -70.6  355 154 79  -1.7  -0.9 | -57.2 -71.0  350 108 56  -1.9  -1.1
 34000 -58.2 -72.8  355 189 97  -2.0  -1.1 | -58.5 -73.3  350 134 69  -2.5  -1.4
 32000 -56.0 -68.8  355 206 106   5.0   2.7 | -56.2 -69.2  350 146 75   5.2   2.8
 30000 -53.0 -63.4  355 219 113   4.7   2.6 | -53.1 -63.6  355 156 80   5.2   2.9
 29000 -50.8 -59.4  355 229 118   7.8   4.3 | -50.9 -59.6  355 167 86   7.8   4.3
 28000 -48.5 -55.3  355 239 123   7.7   4.2 | -48.5 -55.3  355 178 92   7.8   4.3
 27000 -46.2 -51.2  355 250 129   7.7   4.2 | -46.2 -51.2  355 190 98   7.8   4.3
 26000 -43.9 -47.0  355 261 135   8.0   4.4 | -43.9 -47.0  355 202 104   7.5   4.1
 25000 -41.5 -42.7  355 273 140   8.0   4.4 | -41.6 -42.9  355 216 111   7.5   4.1
 24000 -39.1 -38.4  355 284 146   8.0   4.4 | -39.4 -38.9  355 229 118   7.6   4.1
 23000 -36.7 -34.1  360 293 151   8.1   4.5 | -37.0 -34.6  355 241 124   9.0   4.9
 22000 -34.3 -29.7  360 299 154   8.1   4.4 | -34.3 -29.7  355 249 128   8.9   4.9
 21000 -31.9 -25.4  360 306 157   8.2   4.5 | -31.6 -24.9  355 257 132   9.1   5.0
 20000 -29.3 -20.7  360 315 162   6.4   3.5 | -28.8 -19.8  360 262 135   7.1   3.9
 19500 -28.3 -18.9  360 319 164   6.4   3.5 | -27.7 -17.9  360 263 136   7.1   3.9
 19000 -27.4 -17.3  360 323 167   6.4   3.5 | -26.7 -16.1  360 265 136   7.1   3.9
 18500 -26.4 -15.5  360 328 169   6.4   3.5 | -25.6 -14.1  360 266 137   7.1   3.9
 18000 -25.4 -13.7  360 331 170   6.5   3.6 | -24.5 -12.1  360 268 138   7.0   3.8
 17500 -24.4 -11.9  360 333 172   6.4   3.5 | -23.5 -10.3  360 270 139   7.0   3.8
 17000 -23.4 -10.1  360 335 173   7.4   4.1 | -22.4  -8.3  360 273 140   7.5   4.1
 16500 -22.3  -8.1  360 336 173   7.6   4.2 | -21.3  -6.3  360 276 142   7.5   4.1
 16000 -21.2  -6.2  360 338 174   7.7   4.2 | -20.1  -4.2  360 277 143   7.7   4.2
 15500 -20.0  -4.0  360 337 174   7.8   4.3 | -19.0  -2.2  360 273 140   7.8   4.3
 15000 -18.8  -1.8  360 337 174   7.7   4.2 | -17.8  -0.0  360 268 138   7.6   4.2
 14500 -17.7   0.1  360 332 171   7.1   3.9 | -16.7   1.9  360 264 136   7.3   4.0
 14000 -16.7   1.9  360 327 168   7.2   3.9 | -15.6   3.9  360 261 135   7.3   4.0
 13500 -15.6   3.9  360 321 165   7.9   4.3 | -14.5   5.9  360 266 137   7.5   4.1
 13000 -14.4   6.1  360 315 162   7.9   4.3 | -13.4   7.9  360 274 141   7.7   4.2
 12500 -13.1   8.4  360 311 160   8.4   4.6 | -12.1  10.2  360 278 143   8.6   4.7
 12000 -12.0  10.4  360 306 157   7.9   4.3 | -11.0  12.2  360 284 146   7.9   4.3
 11750 -11.4  11.5  360 303 156   8.2   4.5 | -10.4  13.3  360 285 147   7.8   4.3
 11500 -10.7  12.7  360 300 155   8.8   4.8 |  -9.8  14.4  360 283 146   8.3   4.5
 11250 -10.1  13.8  360 297 153   9.6   5.2 |  -9.1  15.6  360 281 144   9.5   5.2
 11000  -9.3  15.3  360 294 151   9.7   5.3 |  -8.4  16.9  360 276 142   9.7   5.3
 10750  -8.6  16.5  360 292 150   9.0   4.9 |  -7.7  18.1  360 271 139   9.0   4.9
 10500  -8.0  17.6  360 290 150   8.0   4.4 |  -7.1  19.2  360 264 136   8.2   4.5
 10250  -7.4  18.7  360 289 149  10.4   5.7 |  -6.4  20.5  360 257 132  10.2   5.6
 10000  -6.5  20.3  360 288 148  12.0   6.6 |  -5.6  21.9  360 252 130  11.1   6.1
  9750  -5.7  21.7  360 287 148  10.0   5.5 |  -4.9  23.2  360 248 128   9.2   5.0
  9500  -5.0  23.0  360 285 147   9.4   5.2 |  -4.2  24.4  360 244 126   8.8   4.8
  9250  -4.2  24.4  360 283 146  10.3   5.6 |  -3.5  25.7  360 240 124   9.5   5.2
  9000  -3.4  25.9  360 282 145  10.5   5.7 |  -2.8  27.0  360 240 123   9.4   5.2
  8750  -2.7  27.1  360 281 145   9.7   5.3 |  -2.2  28.0  360 234 120   8.5   4.7
  8500  -2.0  28.4  360 280 144   9.6   5.2 |  -1.5  29.3  360 227 117   9.1   5.0
  8250  -1.2  29.8  360 279 144  10.2   5.6 |  -0.9  30.4  360 221 114   7.4   4.1
  8000  -0.4  31.3  360 278 143  14.1   7.7 |  -0.6  30.9  360 223 115  -2.9  -1.6
  7750   0.8  33.4  360 278 143  18.4  10.1 |  -1.4  29.5  360 228 117 -14.9  -8.2
  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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