Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 261301
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0601 MST Monday, January 26, 2015

This forecast is for Monday, January 26, 2015:

If the trigger temperature of 62.2 F/16.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 183 ft/min (0.9 m/s)
   Maximum height of thermals.................. 6899 ft MSL (2060 ft AGL)

Forecast maximum temperature................... 53.0 F/12.1 C
Time of trigger temperature.................... None
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................. 6088 ft MSL (1248 ft AGL)
Thermal soaring outlook for Tuesday 01/27...... Poor

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

Remarks...

Sunrise/Sunset.................... 07:25:37 / 17:26:47 MST
Total possible sunshine........... 10 hr 1 min 11 sec (601 min 11 sec)
Altitude of sun at 12:26:35 MST... 32.29 degrees

Upper air data from rawinsonde observation taken on 01/26/2015 at 0500 MST

Freezing level.................. 4933 ft MSL (94 ft AGL)
Additional freezing level....... 13899 ft MSL (9060 ft AGL)
Convective condensation level... 19660 ft MSL (14821 ft AGL)
Lifted condensation level....... 11599 ft MSL (6760 ft AGL)
Lifted index.................... +12.4
K index......................... -3.6

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  -65.1 -85.2   320   12    6   7.5   4.1   91.6 196.9    45.6      M    M
 45000  -57.6 -71.7   360   26   14  -3.9  -2.1   78.4 173.2    40.9      M    M
 40000  -64.7 -84.5   280   17    9  -1.0  -0.6   44.2 111.5    21.3      M    M
 38000  -60.9 -77.6   265   17    9   8.5   4.6   41.1 105.9    19.9      M    M
 36000  -55.8 -68.4   270   20   10   8.5   4.7   40.1 104.2    19.7      M    M
 34000  -50.7 -59.3   290   16    8   9.1   5.0   38.9 102.1    19.4      M    M
 32000  -44.5 -48.1   285   13    7   9.1   5.0   38.4 101.0    19.6      M    M
 30000  -38.7 -37.7   305    9    4   8.1   4.4   38.4 101.1    20.1      M    M
 29000  -36.4 -33.5   355    6    3   7.8   4.3   37.7  99.8    19.8      M    M
 28000  -34.0 -29.2   350    9    5   9.1   5.0   37.0  98.6    19.5      M    M
 27000  -31.4 -24.5   350   12    6   7.8   4.3   36.6  97.8    19.4      M    M
 26000  -29.0 -20.2   350   14    7   8.3   4.6   35.9  96.6    19.1      M    M
 25000  -26.6 -15.9   350   17    9   6.9   3.8   35.3  95.5    18.8      M    M
 24000  -24.3 -11.7   350   17    8   8.0   4.4   34.6  94.3    18.5      M    M
 23000  -21.7  -7.1   350   17    9   8.8   4.8   34.2  93.5    18.4      M    M
 22000  -19.0  -2.2   345   18    9   9.3   5.1   33.9  93.1    18.4      M    M
 21000  -16.2   2.8   345   19   10   9.2   5.0   33.7  92.6    18.4      M    M
 20000  -13.5   7.7   345   20   10   9.2   5.0   33.5  92.4    18.4      M    M
 19500  -12.1  10.2   345   19   10   9.4   5.2   33.4  92.1    18.4      M    M
 19000  -10.9  12.4   340   19   10   7.1   3.9   33.1  91.6    18.3      M    M
 18500   -9.8  14.4   350   18    9   7.4   4.1   32.7  90.8    18.0      M    M
 18000   -8.7  16.3   360   18    9   7.4   4.1   32.2  90.0    17.7      M    M
 17500   -7.0  19.4   015   18    9   7.4   4.1   31.6  88.9    17.3      M    M
 17000   -5.9  21.4   020   19   10   7.4   4.1   31.3  88.3    17.1      M    M
 16500   -4.8  23.4   030   21   11   6.9   3.8   30.9  87.6    16.9      M    M
 16000   -4.0  24.8   040   22   11   4.2   2.3   30.2  86.3    16.3      M    M
 15500   -3.4  25.9   050   24   12   4.2   2.3   29.3  84.7    15.5      M    M
 15000   -2.6  27.3   060   26   13   7.7   4.2   28.5  83.4    15.0      M    M
 14500   -1.3  29.7   055   26   13   8.3   4.6   28.3  82.9    14.8      M    M
 14000   -0.1  31.8   055   26   14   8.8   4.8   28.1  82.5    14.7      M    M
 13500    0.9  33.6   055   28   15   4.8   2.6   27.6  81.6    14.3      M    M
 13000    1.2  34.2   050   30   16  -0.5  -0.3   26.3  79.4    13.2      M    M
 12500    1.2  34.2   050   32   17  -0.1  -0.0   24.8  76.6    11.8      M    M
 12000    1.0  33.8   050   34   17   0.8   0.4   23.1  73.6    10.3      M    M
 11500    1.7  35.1   045   28   14   6.8   3.7   22.3  72.1     9.5      M    M
 11000    2.7  36.9   040   23   12   6.5   3.6   21.8  71.2     9.1      M    M
 10500    3.6  38.5   045   20   10   6.6   3.6   21.2  70.2     8.6      M    M
 10250    4.1  39.4   045   18    9   6.6   3.6   21.0  69.8     8.4      M    M
 10000    4.6  40.3   050   17    9   7.1   3.9   20.7  69.3     8.2      M    M
  9750    5.1  41.2   055   16    8   5.3   2.9   20.5  68.9     8.0      M    M
  9500    5.3  41.5   060   15    8  -0.6  -0.4   19.9  67.9     7.5      M    M
  9250    5.1  41.2   070   14    7  -3.2  -1.8   19.0  66.1     6.5      M    M
  9000    4.9  40.8   075   13    7  -2.6  -1.4   18.0  64.4     5.6      M    M
  8750    4.6  40.3   075   12    6  -2.5  -1.4   17.0  62.6     4.7      M    M
  8500    4.4  39.9   070   10    5  -3.4  -1.9   16.0  60.9     3.7      M    M
  8250    4.2  39.6   065    9    4   0.4   0.2   15.1  59.2     2.8      M    M
  8000    4.4  39.9   060    7    4   4.2   2.3   14.6  58.3     2.3      M    M
  7750    4.7  40.5   050    7    4   3.2   1.8   14.1  57.4     1.8      M    M
  7500    4.9  40.8   035    8    4   3.5   1.9   13.6  56.5     1.3      M    M
  7250    5.2  41.4   025    9    4   3.5   1.9   13.1  55.6     0.9      M    M
  7000    5.4  41.7   015   10    5   3.2   1.8   12.6  54.8     0.4      M    M
  6750    5.5  41.9   025   10    5  -0.8  -0.4   12.0  53.7    -0.2    179  0.9
  6500    5.3  41.5   035   10    5  -3.3  -1.8   11.1  51.9    -1.2    178  0.9
  6250    5.1  41.2   045   11    6  -2.9  -1.6   10.1  50.2    -2.1    177  0.9
  6000    4.9  40.8   055   12    6  -1.8  -1.0    9.2  48.5    -3.1    176  0.9
  5750    4.7  40.5   055    9    5  -6.5  -3.6    8.2  46.8    -4.0    175  0.9
  5500    3.7  38.7   050    6    3 -19.5 -10.7    6.5  43.7    -5.7    197  1.0
  5250    2.3  36.1   040    2    1 -13.8  -7.6    4.3  39.7    -7.9    233  1.2
  5000    1.8  35.2   075    2    1  -3.9  -2.2    3.1  37.5    -9.1    240  1.2

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

           01/26/2015 at 0800 MST          |       01/26/2015 at 1100 MST
                                           |
K index... +1.2  LI... +6.2                | K index... 0.0  LI... +6.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -64.5 -84.1  325  30 15   4.6   2.5 | -64.9 -84.8  335  23 12   4.7   2.6
 45000 -58.9 -74.0  335  23 12  -2.9  -1.6 | -59.1 -74.4  330  17  9  -2.7  -1.5
 40000 -63.2 -81.8  275  28 14  -4.3  -2.3 | -63.0 -81.4  290  28 14  -3.8  -2.1
 38000 -59.6 -75.3  275  23 12   7.4   4.0 | -59.4 -74.9  280  24 12   7.2   3.9
 36000 -55.2 -67.4  275  17  9   7.4   4.0 | -55.1 -67.2  265  20 10   7.2   3.9
 34000 -50.3 -58.5  280  13  7   8.9   4.9 | -50.3 -58.5  255  18  9   8.9   4.9
 32000 -45.0 -49.0  285  12  6   8.9   4.9 | -44.3 -47.7  250  17  9   8.9   4.9
 30000 -39.2 -38.6  295  11  5   8.3   4.6 | -38.9 -38.0  260  16  8   8.8   4.9
 29000 -36.8 -34.2  300  11  5   8.3   4.6 | -36.3 -33.3  265  16  8   8.8   4.9
 28000 -34.3 -29.7  310  11  5   8.3   4.5 | -33.7 -28.7  270  15  8   8.9   4.9
 27000 -31.6 -24.9  330  11  6   9.0   4.9 | -31.1 -24.0  280  12  6   8.3   4.6
 26000 -29.0 -20.2  345  13  7   9.0   4.9 | -28.7 -19.7  295   9  5   8.3   4.6
 25000 -26.3 -15.3  360  16  8   9.0   4.9 | -26.2 -15.2  325   7  3   8.3   4.6
 24000 -23.7 -10.7  005  18  9   8.2   4.5 | -23.6 -10.5  355   8  4   8.8   4.8
 23000 -21.3  -6.3  005  19 10   8.2   4.5 | -21.0  -5.8  010  11  5   8.8   4.8
 22000 -18.9  -2.0  360  20 10   8.2   4.5 | -18.4  -1.1  020  14  7   8.9   4.9
 21000 -16.5   2.3  005  20 10   8.0   4.4 | -16.1   3.0  025  15  8   7.1   3.9
 20000 -14.1   6.6  005  20 10   8.0   4.4 | -14.0   6.8  030  15  8   7.1   3.9
 19500 -12.9   8.8  010  20 10   8.0   4.4 | -12.9   8.8  035  16  8   7.1   3.9
 19000 -11.7  10.9  010  20 10   7.5   4.1 | -11.8  10.8  035  16  8   6.8   3.7
 18500 -10.7  12.7  010  18  9   7.1   3.9 | -10.4  13.3  040  15  8   6.5   3.6
 18000  -9.1  15.6  010  16  8   6.5   3.5 |  -9.4  15.1  045  14  7   6.6   3.6
 17500  -8.2  17.2  015  14  7   6.0   3.3 |  -8.5  16.7  050  13  7   6.6   3.6
 17000  -7.3  18.9  025  12  6   6.0   3.3 |  -7.5  18.5  050  12  6   6.6   3.6
 16500  -6.4  20.5  040  12  6   6.6   3.6 |  -6.6  20.1  060  12  6   6.1   3.4
 16000  -5.4  22.3  055  14  7   6.5   3.6 |  -5.6  21.9  070  13  7   6.0   3.3
 15500  -4.4  24.1  065  16  8   7.8   4.3 |  -4.6  23.7  075  14  7   8.8   4.8
 15000  -3.2  26.2  065  18  9   8.0   4.4 |  -3.2  26.2  080  15  8   9.0   4.9
 14500  -2.0  28.4  070  19 10   7.9   4.3 |  -1.9  28.6  085  16  8   8.6   4.7
 14000  -0.9  30.4  070  21 11   7.8   4.3 |  -0.6  30.9  085  17  9   8.4   4.6
 13500   0.3  32.5  070  22 11   7.4   4.1 |   0.6  33.1  090  18  9   8.0   4.4
 13000   1.3  34.3  075  22 11   6.6   3.6 |   1.7  35.1  090  19 10   7.4   4.0
 12500   2.3  36.1  075  22 11   6.2   3.4 |   2.8  37.0  090  19 10   6.9   3.8
 12000   3.0  37.4  075  21 11   4.2   2.3 |   3.7  38.7  095  19 10   5.6   3.0
 11500   3.6  38.5  075  20 10   3.9   2.2 |   4.5  40.1  095  19 10   5.1   2.8
 11000   3.9  39.0  075  18  9   1.5   0.8 |   5.0  41.0  095  17  9   2.8   1.5
 10500   4.1  39.4  070  16  8   1.7   0.9 |   5.4  41.7  095  16  8   2.6   1.4
 10250   4.2  39.6  070  15  8   1.3   0.7 |   5.5  41.9  095  15  8   1.4   0.7
 10000   4.2  39.6  070  15  8   2.3   1.3 |   5.6  42.1  090  15  8   1.3   0.7
  9750   4.5  40.1  070  14  7   3.7   2.0 |   5.7  42.3  090  14  7   1.8   1.0
  9500   4.7  40.5  070  13  7   2.6   1.4 |   5.7  42.3  085  13  7   1.6   0.9
  9250   4.8  40.6  070  12  6   1.4   0.8 |   5.8  42.4  085  12  6   1.6   0.9
  9000   4.9  40.8  070  11  6   1.0   0.5 |   5.9  42.6  085  12  6   1.4   0.8
  8750   4.9  40.8  070  11  5  -0.0  -0.0 |   6.0  42.8  085  11  6   1.2   0.7
  8500   4.9  40.8  070   9  5  -0.2  -0.1 |   6.1  43.0  080  11  5   1.0   0.5
  8250   4.9  40.8  070   9  5   0.2   0.1 |   6.2  43.2  080  10  5   0.8   0.5
  8000   4.9  40.8  070   8  4   0.1   0.0 |   6.2  43.2  080   9  5   0.9   0.5
  7750   4.9  40.8  075   7  4  -0.3  -0.2 |   6.3  43.3  080   9  5   0.3   0.2
  7500   4.9  40.8  075   7  4  -0.0  -0.0 |   6.3  43.3  080   8  4  -0.2  -0.1
  7250   4.9  40.8  080   7  3   0.4   0.2 |   6.3  43.3  080   8  4  -0.1  -0.1
  7000   5.0  41.0  085   7  3   0.6   0.3 |   6.3  43.3  080   8  4   0.2   0.1
  6750   5.0  41.0  085   6  3  -0.6  -0.3 |   6.3  43.3  080   7  4  -1.1  -0.6
  6500   4.9  40.8  090   7  3  -1.8  -1.0 |   6.1  43.0  080   6  3  -2.8  -1.5
  6250   4.8  40.6  090   7  4  -0.0  -0.0 |   5.9  42.6  085   5  3  -3.6  -2.0
  6000   4.7  40.5  095   7  4  -4.0  -2.2 |   5.6  42.1  090   4  2  -1.2  -0.6
  5750   3.9  39.0  095   7  4 -18.5 -10.1 |   5.8  42.4  095   4  2   6.6   3.6
  5500   2.0  35.6  090   6  3 -31.3 -17.2 |   6.4  43.5  100   3  2  12.5   6.8
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/26/2015 at 1400 MST          |       01/26/2015 at 1700 MST
                                           |
K index... -1.2  LI... +5.6                | K index... -2.7  LI... +5.7
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... M
                                           |
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 -64.5 -84.1  305  18  9   5.0   2.7 | -64.4 -83.9  300  19 10   5.0   2.7
 45000 -58.3 -72.9  295  17  9  -2.4  -1.3 | -58.0 -72.4  290  16  8  -1.5  -0.8
 40000 -61.8 -79.2  295  21 11  -3.3  -1.8 | -60.2 -76.4  280  17  9  -2.1  -1.1
 38000 -58.8 -73.8  280  21 11   6.3   3.5 | -57.8 -72.0  270  19 10   5.2   2.8
 36000 -55.0 -67.0  270  22 11   6.3   3.5 | -54.7 -66.5  255  22 11   5.2   2.9
 34000 -49.8 -57.6  265  21 11   8.8   4.8 | -49.9 -57.8  255  19 10   8.5   4.7
 32000 -44.6 -48.3  275  18  9   8.8   4.8 | -44.8 -48.6  280  14  7   8.5   4.7
 30000 -39.2 -38.6  275  18  9   9.0   4.9 | -39.5 -39.1  280  13  6   9.0   4.9
 29000 -36.5 -33.7  270  19 10   9.0   4.9 | -36.8 -34.2  275  13  7   9.0   4.9
 28000 -33.8 -28.8  270  20 10   9.0   5.0 | -34.1 -29.4  270  14  7   9.0   5.0
 27000 -31.3 -24.3  270  17  9   8.4   4.6 | -31.6 -24.9  265  13  6   8.4   4.6
 26000 -28.8 -19.8  270  13  7   8.4   4.6 | -29.0 -20.2  265  11  5   8.4   4.6
 25000 -26.2 -15.2  270   9  4   8.4   4.6 | -26.5 -15.7  265   9  4   8.5   4.6
 24000 -23.6 -10.5  285   5  3   8.9   4.9 | -23.9 -11.0  265   6  3   8.8   4.8
 23000 -21.0  -5.8  340   3  2   8.9   4.9 | -21.3  -6.3  250   2  1   8.8   4.8
 22000 -18.3  -0.9  025   5  3   9.1   5.0 | -18.6  -1.5  115   2  1   8.9   4.9
 21000 -16.0   3.2  050   8  4   7.1   3.9 | -16.3   2.7  110   5  3   7.0   3.9
 20000 -13.9   7.0  060  11  6   7.1   3.9 | -14.2   6.4  115   9  5   7.0   3.8
 19500 -12.3   9.9  065  13  7   7.2   4.0 | -12.7   9.1  115  11  6   7.1   3.9
 19000 -11.3  11.7  070  14  7   5.8   3.2 | -11.7  10.9  115  12  6   5.8   3.2
 18500 -10.4  13.3  075  14  7   6.0   3.3 | -10.9  12.4  120  13  7   5.9   3.2
 18000  -9.6  14.7  075  14  7   6.2   3.4 | -10.0  14.0  125  13  7   6.3   3.4
 17500  -8.6  16.5  080  12  6   6.5   3.6 |  -9.0  15.8  125  13  7   6.8   3.7
 17000  -7.7  18.1  090  11  6   6.5   3.6 |  -8.0  17.6  125  13  6   6.7   3.7
 16500  -6.6  20.1  095  11  6   7.3   4.0 |  -6.9  19.6  125  12  6   8.7   4.8
 16000  -5.6  21.9  095  11  6   7.2   3.9 |  -5.6  21.9  125  12  6   8.5   4.7
 15500  -4.4  24.1  100  12  6   8.5   4.7 |  -4.3  24.3  130  12  6   7.9   4.4
 15000  -3.1  26.4  100  13  7   8.7   4.7 |  -3.2  26.2  130  12  6   7.8   4.3
 14500  -1.8  28.8  100  14  7   8.3   4.6 |  -2.0  28.4  135  12  6   7.6   4.2
 14000  -0.6  30.9  105  15  8   8.1   4.4 |  -0.9  30.4  140  12  6   7.3   4.0
 13500   0.6  33.1  105  16  8   8.0   4.4 |   0.2  32.4  145  13  7   7.3   4.0
 13000   1.8  35.2  110  17  9   8.0   4.4 |   1.2  34.2  150  13  7   7.2   3.9
 12500   3.0  37.4  110  18  9   7.8   4.3 |   2.3  36.1  155  14  7   7.2   4.0
 12000   4.0  39.2  110  18  9   6.8   3.7 |   3.4  38.1  160  14  7   7.4   4.1
 11500   5.0  41.0  110  17  9   6.5   3.6 |   4.5  40.1  160  15  7   7.4   4.0
 11000   5.8  42.4  110  16  8   4.6   2.5 |   5.5  41.9  165  15  8   6.6   3.6
 10500   6.5  43.7  110  15  8   4.3   2.4 |   6.5  43.7  165  15  7   6.5   3.6
 10250   6.7  44.1  110  15  8   2.5   1.4 |   6.9  44.4  165  14  7   4.8   2.6
 10000   6.8  44.2  110  14  7   2.6   1.4 |   7.2  45.0  165  14  7   4.5   2.5
  9750   7.1  44.8  110  13  7   3.5   1.9 |   7.6  45.7  165  14  7   5.4   3.0
  9500   7.3  45.1  110  12  6   2.9   1.6 |   8.0  46.4  165  13  7   4.6   2.5
  9250   7.5  45.5  110  11  6   2.3   1.3 |   8.2  46.8  165  13  7   2.9   1.6
  9000   7.6  45.7  110  10  5   1.9   1.0 |   8.4  47.1  165  12  6   2.1   1.2
  8750   7.7  45.9  105  10  5   1.5   0.8 |   8.5  47.3  165  11  6   2.5   1.3
  8500   7.8  46.0  105   9  5   1.1   0.6 |   8.7  47.7  165  10  5   1.7   0.9
  8250   7.8  46.0  100   8  4   0.8   0.5 |   8.7  47.7  165  10  5   0.7   0.4
  8000   7.9  46.2  100   8  4   0.9   0.5 |   8.7  47.7  165   9  5   0.7   0.4
  7750   7.9  46.2  095   8  4   0.5   0.3 |   8.8  47.8  160   8  4   0.2   0.1
  7500   7.9  46.2  095   7  4  -0.7  -0.4 |   8.7  47.7  160   8  4  -0.5  -0.3
  7250   7.8  46.0  095   7  3  -1.2  -0.6 |   8.6  47.5  155   7  3  -0.5  -0.3
  7000   7.7  45.9  090   6  3  -1.6  -0.9 |   8.6  47.5  150   6  3  -0.8  -0.4
  6750   7.6  45.7  090   6  3   0.7   0.4 |   8.5  47.3  145   5  3   0.7   0.4
  6500   7.8  46.0  090   5  2   3.5   1.9 |   8.6  47.5  140   5  2   2.4   1.3
  6250   7.9  46.2  090   4  2   2.8   1.5 |   8.7  47.7  130   4  2   1.8   1.0
  6000   8.1  46.6  095   3  2   4.4   2.4 |   8.8  47.8  120   4  2   3.6   2.0
  5750   8.6  47.5  095   3  1  10.6   5.8 |   9.0  48.2  115   4  2   1.7   1.0
  5500   9.6  49.3  100   3  1  16.5   9.1 |   8.8  47.8  110   3  1  -6.5  -3.6
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 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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