Soaring Guidance
Issued by NWS Grand Junction, CO

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650
UXUS97 KGJT 291232
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0532 MST Tuesday, November 29, 2016

This forecast is for Tuesday, November 29, 2016:

If the trigger temperature of 36.5 F/2.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 144 ft/min (0.7 m/s)
   Maximum height of thermals.................. 11509 ft MSL (6670 ft AGL)

Forecast maximum temperature................... 39.0 F/4.3 C
Time of trigger temperature.................... 1215 MST
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................. 5493 ft MSL (654 ft AGL)
Thermal soaring outlook for Wednesday 11/30.... Poor

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

Remarks...

Sunrise/Sunset.................... 07:12:55 / 16:52:26 MST
Total possible sunshine........... 9 hr 39 min 31 sec (579 min 31 sec)
Altitude of sun at 12:02:49 MST... 29.30 degrees

Upper air data from rawinsonde observation taken on 11/29/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 9853 ft MSL (5014 ft AGL)
Lifted condensation level....... 10373 ft MSL (5534 ft AGL)
Lifted index.................... +2.4
K index......................... +15.5

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  -53.3 -63.9   305   31   16   2.7   1.5  115.0 239.0    63.0      M    M
 45000  -49.1 -56.4   300   34   18   0.8   0.4   97.1 206.8    56.4      M    M
 40000  -46.0 -50.8   310   30   15   3.3   1.8   78.7 173.6    48.3      M    M
 38000  -44.9 -48.8   310   39   20  -6.7  -3.7   70.4 158.7    44.2      M    M
 36000  -43.7 -46.7   300   33   17   4.3   2.4   63.3 145.9    40.5      M    M
 34000  -43.7 -46.7   315   28   14   1.3   0.7   54.8 130.7    35.6      M    M
 32000  -43.8 -46.8   330   27   14   2.9   1.6   46.4 115.6    30.5      M    M
 30000  -43.2 -45.8   305   20   10  -1.4  -0.8   39.3 102.7    26.0      M    M
 29000  -46.7 -52.1   330   21   11  -4.1  -2.2   30.5  86.9    19.9      M    M
 28000  -48.5 -55.3   320   14    7  -6.9  -3.8   24.3  75.8    15.4      M    M
 27000  -49.8 -57.6   030   14    7  -9.1  -5.0   18.7  65.6    11.3      M    M
 26000  -50.4 -58.7   040   17    9   8.2   4.5   14.1  57.4     7.9      M    M
 25000  -47.9 -54.2   355   13    7   6.9   3.8   13.5  56.3     7.6      M    M
 24000  -45.6 -50.1   340   14    7   9.6   5.3   12.7  54.8     7.0      M    M
 23000  -42.8 -45.0   330   15    8   9.3   5.1   12.5  54.4     6.9      M    M
 22000  -40.0 -40.0   330   14    7   9.4   5.1   12.3  54.2     6.9      M    M
 21000  -37.2 -35.0   325   13    7   8.8   4.9   12.2  54.0     6.9      M    M
 20000  -34.0 -29.2   275   14    7   8.7   4.8   11.8  53.2     6.6      M    M
 19500  -32.6 -26.7   285   14    7   8.7   4.8   11.5  52.8     6.5      M    M
 19000  -31.3 -24.3   295   14    7   8.7   4.8   11.3  52.4     6.3      M    M
 18500  -30.0 -22.0   300   15    8   8.7   4.8   11.2  52.1     6.2      M    M
 18000  -28.8 -19.8   310   16    8   7.5   4.1   11.0  51.8     6.1      M    M
 17500  -27.8 -18.0   315   16    8   6.5   3.5   10.4  50.8     5.6      M    M
 17000  -26.8 -16.2   320   16    8   6.5   3.6    9.9  49.8     5.2      M    M
 16500  -25.9 -14.6   320   17    9   6.5   3.6    9.3  48.7     4.7      M    M
 16000  -24.9 -12.8   325   17    9   6.6   3.6    8.7  47.7     4.2      M    M
 15500  -24.0 -11.2   345   20   10   3.7   2.0    8.1  46.5     3.6      M    M
 15000  -23.7 -10.7   360   24   12   2.0   1.1    6.9  44.4     2.5      M    M
 14500  -22.8  -9.0   360   22   11   9.9   5.4    6.2  43.2     2.0      M    M
 14000  -21.4  -6.5   005   20   10   9.2   5.0    6.1  43.0     1.9      M    M
 13500  -20.1  -4.2   010   20   10   9.3   5.1    6.0  42.8     1.8      M    M
 13000  -18.8  -1.8   015   19   10   7.7   4.2    5.8  42.4     1.6      M    M
 12500  -17.7   0.1   020   19   10   8.2   4.5    5.5  41.8     1.3      M    M
 12000  -16.8   1.8   025   19   10   3.3   1.8    4.8  40.7     0.7      M    M
 11500  -16.0   3.2   025   20   10   7.1   3.9    4.1  39.4    -0.0    543  2.8
 11000  -15.0   5.0   020   20   10   6.9   3.8    3.7  38.6    -0.5    498  2.5
 10500  -14.0   6.8   020   21   11   7.2   3.9    3.2  37.8    -0.9    452  2.3
 10250  -13.4   7.9   015   21   11   8.3   4.6    3.1  37.5    -1.1    427  2.2
 10000  -12.7   9.1   015   21   11   8.7   4.8    3.0  37.3    -1.1    401  2.0
  9750  -12.1  10.2   015   22   11   8.8   4.8    2.9  37.2    -1.2    374  1.9
  9500  -11.4  11.5   015   22   11   9.4   5.2    2.8  37.1    -1.3    346  1.8
  9250  -10.7  12.7   010   21   11   9.7   5.3    2.8  37.1    -1.3    317  1.6
  9000  -10.0  14.0   010   21   11   9.7   5.3    2.8  37.1    -1.3    288  1.5
  8750   -9.2  15.4   005   20   10   9.3   5.1    2.8  37.1    -1.3    259  1.3
  8500   -8.6  16.5   360   20   10   8.8   4.8    2.7  36.9    -1.4    232  1.2
  8250   -7.9  17.8   355   19   10   8.9   4.9    2.7  36.8    -1.5    204  1.0
  8000   -7.3  18.9   350   19   10   8.9   4.9    2.6  36.7    -1.5    177  0.9
  7750   -6.6  20.1   350   18    9   8.9   4.9    2.6  36.6    -1.6    150  0.8
  7500   -6.0  21.2   345   17    9   8.9   4.9    2.5  36.5    -1.7    123  0.6
  7250   -5.3  22.5   345   15    8   8.9   4.9    2.4  36.4    -1.8     96  0.5
  7000   -4.6  23.7   340   14    7   8.9   4.9    2.4  36.3    -1.8     69  0.3
  6750   -4.0  24.8   335   14    7   8.9   4.9    2.3  36.1    -1.9     42  0.2
  6500   -3.3  26.1   335   13    7   8.9   4.9    2.2  36.0    -2.0     14  0.1
  6250   -2.7  27.1   330   13    7   8.8   4.8    2.2  35.9    -2.1      M    M
  6000   -2.0  28.4   325   13    7   9.3   5.1    2.1  35.8    -2.2      M    M
  5750   -1.3  29.7   325   12    6   7.6   4.1    2.0  35.6    -2.3      M    M
  5500   -1.0  30.2   325   10    5   0.6   0.3    1.6  34.9    -2.7      M    M
  5250   -1.1  30.0   325    9    5   1.5   0.8    0.8  33.5    -3.5      M    M
  5000   -0.7  30.7   325    7    4   7.8   4.3    0.5  32.9    -3.9      M    M

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

           11/29/2016 at 0800 MST          |       11/29/2016 at 1100 MST
                                           |
K index... +14.3  LI... +1.5               | K index... +12.5  LI... +2.6
CAPE... 0.0  CIN... -0.9                   | CAPE... +8.1  CIN... -0.9
                                           |
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 -53.3 -63.9  300  32 17   2.9   1.6 | -53.6 -64.5  310  31 16   2.7   1.5
 45000 -49.0 -56.2  305  33 17   2.9   1.6 | -49.3 -56.7  315  33 17   2.7   1.5
 40000 -45.6 -50.1  325  30 16   2.1   1.1 | -46.0 -50.8  325  30 16   2.2   1.2
 38000 -44.4 -47.9  330  30 15   1.3   0.7 | -44.7 -48.5  330  29 15   1.0   0.6
 36000 -43.6 -46.5  335  27 14   1.2   0.7 | -44.2 -47.6  335  28 15   0.9   0.5
 34000 -42.9 -45.2  340  25 13   1.2   0.7 | -43.6 -46.5  345  28 14   0.9   0.5
 32000 -43.9 -47.0  350  22 11  -3.9  -2.1 | -44.9 -48.8  355  25 13  -4.2  -2.3
 30000 -46.2 -51.2  010  20 10  -3.9  -2.1 | -47.7 -53.9  020  20 11  -4.1  -2.3
 29000 -47.3 -53.1  020  19 10  -1.7  -0.9 | -48.3 -54.9  035  20 10   2.1   1.1
 28000 -47.5 -53.5  030  19 10  -0.6  -0.3 | -47.7 -53.9  045  19 10   1.9   1.0
 27000 -47.7 -53.9  040  20 10  -0.5  -0.3 | -47.2 -53.0  060  20 10   1.9   1.0
 26000 -47.9 -54.2  045  21 11   1.7   0.9 | -46.6 -51.9  070  21 11   4.4   2.4
 25000 -46.0 -50.8  040  21 11   6.7   3.7 | -44.6 -48.3  065  19 10   6.6   3.6
 24000 -44.0 -47.2  030  22 11   6.7   3.7 | -42.7 -44.9  060  17  9   6.6   3.6
 23000 -42.0 -43.6  025  23 12   7.3   4.0 | -40.7 -41.3  050  15  8   7.2   3.9
 22000 -39.6 -39.3  020  23 12   8.2   4.5 | -38.4 -37.1  035  17  9   7.6   4.2
 21000 -37.1 -34.8  015  23 12   8.2   4.5 | -36.1 -33.0  025  19 10   7.6   4.2
 20000 -34.8 -30.6  010  23 12   6.4   3.5 | -33.9 -29.0  015  22 11   7.3   4.0
 19500 -33.8 -28.8  005  22 11   6.6   3.6 | -32.8 -27.0  010  23 12   7.3   4.0
 19000 -32.8 -27.0  005  21 11   6.6   3.6 | -31.7 -25.1  010  24 12   7.3   4.0
 18500 -31.8 -25.2  360  20 10   6.6   3.6 | -30.6 -23.1  005  25 13   7.3   4.0
 18000 -30.8 -23.4  360  20 10   6.5   3.6 | -29.5 -21.1  005  26 13   7.1   3.9
 17500 -29.7 -21.5  355  19 10   8.1   4.5 | -28.6 -19.5  360  26 13   5.3   2.9
 17000 -28.5 -19.3  355  18  9   8.0   4.4 | -27.8 -18.0  360  25 13   5.4   3.0
 16500 -27.3 -17.1  355  17  9   8.6   4.7 | -26.9 -16.4  355  25 13   6.1   3.3
 16000 -26.0 -14.8  350  17  9   8.7   4.8 | -26.0 -14.8  350  23 12   6.1   3.3
 15500 -24.7 -12.5  350  16  8   8.5   4.6 | -25.1 -13.2  350  22 11   6.9   3.8
 15000 -23.5 -10.3  350  16  8   8.2   4.5 | -24.0 -11.2  345  21 11   7.3   4.0
 14500 -22.3  -8.1  350  15  8   7.8   4.3 | -22.4  -8.3  345  18 10   7.3   4.0
 14000 -21.3  -6.3  350  14  7   6.7   3.7 | -21.3  -6.3  340  16  8   7.3   4.0
 13500 -19.8  -3.6  355  12  6   6.8   3.7 | -20.2  -4.4  345  14  7   7.4   4.1
 13000 -18.8  -1.8  005  11  6   6.7   3.7 | -19.1  -2.4  350  12  6   7.4   4.1
 12500 -17.8  -0.0  015  10  5   6.9   3.8 | -18.0  -0.4  005  11  6   7.3   4.0
 12000 -16.7   1.9  025  11  6   6.9   3.8 | -16.9   1.6  020  12  6   7.3   4.0
 11500 -15.7   3.7  035  13  6   7.9   4.3 | -15.8   3.6  030  13  7   7.8   4.3
 11000 -14.4   6.1  040  15  8   8.2   4.5 | -14.6   5.7  035  15  8   8.0   4.4
 10500 -13.3   8.1  045  17  9   7.5   4.1 | -13.6   7.5  040  17  9   6.7   3.7
 10250 -12.7   9.1  045  18  9   6.9   3.8 | -13.1   8.4  040  18  9   6.1   3.3
 10000 -12.2  10.0  045  19 10   8.7   4.8 | -12.6   9.3  040  19 10   9.1   5.0
  9750 -11.5  11.3  045  19 10   9.3   5.1 | -11.8  10.8  040  20 10   9.6   5.3
  9500 -10.9  12.4  045  18  9   7.8   4.3 | -11.2  11.8  035  19 10   7.0   3.8
  9250 -10.3  13.5  040  17  9   8.4   4.6 | -10.7  12.7  030  18  9   7.6   4.2
  9000  -9.7  14.5  040  16  8   7.5   4.1 | -10.1  13.8  025  17  9   7.7   4.2
  8750  -9.2  15.4  035  15  8   7.4   4.1 |  -9.5  14.9  025  15  8   8.4   4.6
  8500  -8.6  16.5  035  16  8   8.3   4.6 |  -8.9  16.0  025  14  7   8.6   4.7
  8250  -8.0  17.6  030  16  8   7.8   4.3 |  -8.3  17.1  020  13  7   8.6   4.7
  8000  -7.4  18.7  025  17  9   9.0   4.9 |  -7.6  18.3  020  12  6   9.5   5.2
  7750  -6.7  19.9  025  16  8   8.8   4.8 |  -6.9  19.6  015  12  6   9.4   5.2
  7500  -6.1  21.0  020  15  8   7.6   4.2 |  -6.3  20.7  015  11  6   8.5   4.7
  7250  -5.5  22.1  020  14  7   7.7   4.2 |  -5.6  21.9  015  11  5   9.4   5.2
  7000  -5.0  23.0  020  13  7   6.6   3.6 |  -4.9  23.2  015  10  5  10.3   5.7
  6750  -4.6  23.7  020  11  6   5.1   2.8 |  -4.1  24.6  015   9  5   9.6   5.3
  6500  -4.2  24.4  015   9  4   4.8   2.6 |  -3.4  25.9  015   9  5   9.5   5.2
  6250  -3.9  25.0  015   6  3   3.0   1.6 |  -2.7  27.1  015   8  4  10.6   5.8
  6000  -3.8  25.2  010   5  2   1.3   0.7 |  -1.8  28.8  010   8  4  10.9   6.0
  5750  -3.7  25.3  010   3  1   2.5   1.4 |  -1.1  30.0  010   7  4  10.2   5.6
  5500  -3.5  25.7  060   1  0   2.8   1.5 |  -0.3  31.5  010   7  3   9.9   5.4
  5250  -3.3  26.1  060   1  0   2.4   1.3 |   0.4  32.7  010   7  4  10.4   5.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           11/29/2016 at 1400 MST          |       11/29/2016 at 1700 MST
                                           |
K index... +8.6  LI... +3.6                | K index... +6.0  LI... +4.6
CAPE... +7.3  CIN... -1.1                  | CAPE... +0.5  CIN... -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 -53.7 -64.7  310  32 17   2.7   1.5 | -54.5 -66.1  315  32 16   3.0   1.7
 45000 -49.5 -57.1  320  34 18   2.7   1.5 | -50.0 -58.0  325  36 19   3.0   1.7
 40000 -46.3 -51.3  330  35 18   2.1   1.1 | -46.4 -51.5  335  40 21   2.3   1.3
 38000 -45.2 -49.4  335  35 18   0.5   0.3 | -45.2 -49.4  340  41 21  -0.4  -0.2
 36000 -44.8 -48.6  340  35 18   0.5   0.3 | -45.3 -49.5  345  41 21  -0.2  -0.1
 34000 -44.5 -48.1  345  34 18   0.6   0.3 | -45.4 -49.7  350  41 21  -0.2  -0.1
 32000 -46.0 -50.8  355  28 15  -3.5  -1.9 | -46.6 -51.9  355  34 18  -2.6  -1.4
 30000 -48.1 -54.6  015  23 12  -3.3  -1.8 | -48.2 -54.8  010  26 13  -2.5  -1.4
 29000 -48.2 -54.8  025  20 10   3.4   1.9 | -47.8 -54.0  015  22 11   4.1   2.3
 28000 -47.1 -52.8  040  17  9   3.5   1.9 | -46.5 -51.7  025  17  9   4.3   2.4
 27000 -46.0 -50.8  060  15  8   3.5   1.9 | -45.2 -49.4  035  14  7   4.3   2.4
 26000 -44.9 -48.8  075  15  8   5.3   2.9 | -43.9 -47.0  055  11  6   5.6   3.1
 25000 -43.1 -45.6  075  14  7   6.1   3.3 | -42.1 -43.8  055  10  5   5.9   3.2
 24000 -41.3 -42.3  070  12  6   6.1   3.3 | -40.3 -40.5  055   9  5   5.9   3.2
 23000 -39.4 -38.9  065  11  6   7.2   4.0 | -38.5 -37.3  050   8  4   7.2   4.0
 22000 -37.1 -34.8  060   9  4   7.7   4.2 | -36.2 -33.2  040   7  3   7.6   4.1
 21000 -34.8 -30.6  045   7  3   7.7   4.2 | -34.0 -29.2  020   6  3   7.6   4.1
 20000 -32.6 -26.7  025   7  4   7.1   3.9 | -31.8 -25.2  010   6  3   6.8   3.8
 19500 -31.5 -24.7  020   9  5   7.1   3.9 | -30.7 -23.3  010   7  4   6.9   3.8
 19000 -30.4 -22.7  015  12  6   7.1   3.9 | -29.7 -21.5  010   8  4   6.9   3.8
 18500 -29.4 -20.9  015  14  7   7.1   3.9 | -28.7 -19.7  010   9  5   6.9   3.8
 18000 -28.3 -18.9  015  16  8   7.1   3.9 | -27.7 -17.9  010  10  5   6.9   3.8
 17500 -27.3 -17.1  010  18 10   6.7   3.7 | -26.6 -15.9  010  12  6   6.9   3.8
 17000 -26.3 -15.3  005  21 11   7.0   3.8 | -25.6 -14.1  010  13  7   7.1   3.9
 16500 -25.4 -13.7  360  23 12   4.5   2.5 | -24.7 -12.5  005  15  8   4.9   2.7
 16000 -24.7 -12.5  360  25 13   4.5   2.5 | -24.0 -11.2  360  16  8   5.1   2.8
 15500 -24.0 -11.2  355  27 14   4.8   2.7 | -23.0  -9.4  350  19 10   2.8   1.6
 15000 -22.9  -9.2  355  27 14   4.8   2.6 | -22.6  -8.7  350  21 11   2.7   1.5
 14500 -22.1  -7.8  355  26 13   6.5   3.6 | -21.9  -7.4  350  22 11   6.3   3.4
 14000 -21.2  -6.2  355  24 12   6.3   3.4 | -21.0  -5.8  350  21 11   5.9   3.2
 13500 -20.2  -4.4  350  22 11   7.6   4.1 | -20.1  -4.2  350  20 10   6.6   3.6
 13000 -19.0  -2.2  350  19 10   7.5   4.1 | -19.2  -2.6  355  18 10   6.5   3.5
 12500 -17.9  -0.2  350  17  9   7.7   4.2 | -18.2  -0.8  355  17  9   7.6   4.2
 12000 -16.8   1.8  355  15  8   7.6   4.2 | -17.0   1.4  350  15  8   7.6   4.1
 11500 -15.6   3.9  005  14  7   8.0   4.4 | -15.9   3.4  355  13  7   7.7   4.2
 11000 -14.5   5.9  015  14  7   8.1   4.4 | -14.8   5.4  005  12  6   7.7   4.2
 10500 -13.4   7.9  020  14  7   6.9   3.8 | -13.7   7.3  015  12  6   7.3   4.0
 10250 -12.9   8.8  020  14  7   6.2   3.4 | -13.2   8.2  015  12  6   6.5   3.6
 10000 -12.4   9.7  025  15  8   9.4   5.2 | -12.6   9.3  020  12  6   9.7   5.3
  9750 -11.5  11.3  025  14  7  10.6   5.8 | -11.8  10.8  025  13  7  10.8   5.9
  9500 -10.9  12.4  025  13  7   8.2   4.5 | -11.1  12.0  025  13  7   8.3   4.6
  9250 -10.2  13.6  020  13  7   8.6   4.7 | -10.5  13.1  025  13  7   9.2   5.0
  9000  -9.6  14.7  020  12  6   9.4   5.1 |  -9.8  14.4  025  13  7   8.2   4.5
  8750  -8.8  16.2  020  12  6   9.8   5.4 |  -9.2  15.4  020  13  7   8.8   4.8
  8500  -8.2  17.2  020  11  6   9.1   5.0 |  -8.5  16.7  020  13  7   9.9   5.4
  8250  -7.5  18.5  020  11  6   9.5   5.2 |  -7.8  18.0  020  12  6   9.7   5.3
  8000  -6.7  19.9  020  11  5  10.5   5.8 |  -7.0  19.4  015  12  6  10.2   5.6
  7750  -6.0  21.2  020  10  5   9.9   5.5 |  -6.3  20.7  015  12  6   9.9   5.4
  7500  -5.3  22.5  020  10  5   8.6   4.7 |  -5.6  21.9  015  11  6   9.5   5.2
  7250  -4.6  23.7  025  10  5   9.7   5.3 |  -4.8  23.4  015  11  6   9.7   5.3
  7000  -3.8  25.2  025  10  5  10.6   5.8 |  -4.1  24.6  015  11  6   9.8   5.4
  6750  -3.0  26.6  025  10  5   9.9   5.4 |  -3.4  25.9  015  11  5   9.2   5.0
  6500  -2.3  27.9  025   9  5   9.8   5.4 |  -2.7  27.1  015  10  5   9.2   5.0
  6250  -1.5  29.3  025   9  5  10.9   6.0 |  -2.0  28.4  020   9  5   9.7   5.3
  6000  -0.7  30.7  025   9  4  10.9   6.0 |  -1.3  29.7  020   8  4   9.9   5.5
  5750   0.1  32.2  025   8  4   9.3   5.1 |  -0.6  30.9  025   7  4   6.7   3.7
  5500   0.7  33.3  025   8  4   9.1   5.0 |  -0.3  31.5  030   5  3   0.4   0.2
  5250   1.5  34.7  025   8  4  11.1   6.1 |  -0.5  31.1  025   5  2  -2.6  -1.4
  5000     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) 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 at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  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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