Soaring Guidance
Issued by NWS Grand Junction, CO

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UXUS97 KGJT 281234
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0634 MDT Tuesday, March 28, 2017

This forecast is for Tuesday, March 28, 2017:

If the trigger temperature of 50.1 F/10.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 74 ft/min (0.4 m/s)
   Maximum height of thermals.................. 11251 ft MSL (6412 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8386 ft MSL (3547 ft AGL)
Thermal soaring outlook for Wednesday 03/29.... Poor

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

Remarks...

Sunrise/Sunset.................... 07:04:24 / 19:33:19 MDT
Total possible sunshine........... 12 hr 28 min 55 sec (748 min 55 sec)
Altitude of sun at 13:19:01 MDT... 54.18 degrees

Upper air data from rawinsonde observation taken on 03/28/2017 at 0600 MDT

Freezing level.................. 7951 ft MSL (3112 ft AGL)
Convective condensation level... 9216 ft MSL (4377 ft AGL)
Lifted condensation level....... 10174 ft MSL (5335 ft AGL)
Lifted index.................... +0.3
K index......................... +21.2

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  -55.6 -68.1   225   20   10  -2.1  -1.2  109.7 229.5    55.1      M    M
 45000  -54.6 -66.3   230   35   18  -1.0  -0.6   86.5 187.6    44.8      M    M
 40000  -54.2 -65.6   240   27   14   1.2   0.7   63.9 147.0    33.2      M    M
 38000  -53.1 -63.6   220   35   18 -17.5  -9.6   56.6 134.0    29.3      M    M
 36000  -56.6 -69.9   215   39   20   5.0   2.7   42.8 109.0    20.6      M    M
 34000  -51.9 -61.4   195   46   24   7.3   4.0   40.1 104.3    19.3      M    M
 32000  -48.6 -55.5   205   49   25  -1.6  -0.9   36.6  97.8    17.2      M    M
 30000  -50.1 -58.2   200    9    5  -0.8  -0.5   26.6  79.9    10.3      M    M
 29000  -47.7 -53.9   180   11    6   8.9   4.9   25.9  78.6     9.9      M    M
 28000  -45.1 -49.2   200   10    5   9.0   5.0   25.5  77.9     9.7      M    M
 27000  -42.3 -44.1   185   13    7   9.2   5.1   25.2  77.4     9.6      M    M
 26000  -39.5 -39.1   175   17    9   9.2   5.1   25.1  77.1     9.6      M    M
 25000  -36.9 -34.4   180   12    6   8.5   4.7   24.7  76.4     9.4      M    M
 24000  -34.4 -29.9   185   10    5   9.1   5.0   24.2  75.6     9.1      M    M
 23000  -31.7 -25.1   190    9    4   8.2   4.5   23.9  75.0     9.0      M    M
 22000  -29.2 -20.6   190    8    4   8.4   4.6   23.3  73.9     8.6      M    M
 21000  -26.7 -16.1   185    8    4   8.4   4.6   22.8  73.1     8.3      M    M
 20000  -24.2 -11.6   185    7    4   8.2   4.5   22.4  72.4     8.0      M    M
 19500  -23.0  -9.4   195    7    4   7.9   4.3   22.1  71.8     7.8      M    M
 19000  -21.3  -6.3   210    8    4   7.9   4.3   21.6  70.9     7.4      M    M
 18500  -20.1  -4.2   220    9    5   8.1   4.4   21.3  70.4     7.2      M    M
 18000  -18.8  -1.8   225    8    4   8.1   4.5   21.1  70.0     7.1      M    M
 17500  -17.8  -0.0   235    7    3   6.5   3.6   20.6  69.1     6.6      M    M
 17000  -16.8   1.8   245    6    3   6.8   3.7   20.1  68.1     6.2      M    M
 16500  -15.8   3.6   265    5    3   6.8   3.7   19.6  67.3     5.8      M    M
 16000  -14.8   5.4   280    5    2   6.8   3.7   19.1  66.4     5.4      M    M
 15500  -13.8   7.2   290    4    2   6.5   3.6   18.5  65.4     4.9      M    M
 15000  -12.9   8.8   305    3    2   6.6   3.6   18.0  64.4     4.4      M    M
 14500  -11.9  10.6   330    3    1   6.6   3.6   17.5  63.5     3.9      M    M
 14000  -10.9  12.4   350    3    2   7.3   4.0   17.0  62.6     3.5      M    M
 13500   -9.8  14.4   350    4    2   7.5   4.1   16.6  61.9     3.1      M    M
 13000   -8.9  16.0   355    4    2   5.1   2.8   16.0  60.9     2.6      M    M
 12500   -8.1  17.4   355    5    2   7.7   4.2   15.4  59.8     2.0      M    M
 12000   -7.7  18.1   355    5    3   1.9   1.0   14.3  57.8     0.9      M    M
 11500   -6.8  19.8   350    5    3   5.7   3.1   13.7  56.6     0.3      M    M
 11000   -5.9  21.4   345    5    3   6.0   3.3   13.0  55.5    -0.3    453  2.3
 10500   -5.1  22.8   345    6    3   6.0   3.3   12.5  54.4    -0.9    412  2.1
 10250   -4.6  23.7   340    6    3   6.0   3.3   12.2  53.9    -1.2    391  2.0
 10000   -4.2  24.4   340    6    3   6.1   3.3   11.9  53.4    -1.5    371  1.9
  9750   -3.7  25.3   340    6    3   6.6   3.6   11.6  52.9    -1.7    350  1.8
  9500   -3.2  26.2   340    4    2   6.9   3.8   11.4  52.5    -2.0    327  1.7
  9250   -2.7  27.1   345    3    2   6.9   3.8   11.2  52.1    -2.2    305  1.5
  9000   -2.2  28.0   350    2    1   6.9   3.8   11.0  51.7    -2.4    282  1.4
  8750   -1.7  28.9   350    2    1   6.9   3.8   10.7  51.3    -2.6    260  1.3
  8500   -1.2  29.8   355    2    1   6.9   3.8   10.5  50.9    -2.9    237  1.2
  8250   -0.7  30.7   360    1    1   6.9   3.8   10.3  50.6    -3.1    215  1.1
  8000   -0.2  31.6   005    1    1   6.9   3.8   10.1  50.2    -3.3    192  1.0
  7750    0.3  32.5   355    2    1   6.9   3.8    9.9  49.8    -3.5    169  0.9
  7500    0.8  33.4   350    2    1   6.9   3.8    9.7  49.4    -3.8    147  0.7
  7250    1.3  34.3   345    3    2   6.9   3.8    9.4  49.0    -4.0    124  0.6
  7000    1.8  35.2   345    4    2   6.9   3.8    9.2  48.6    -4.2    102  0.5
  6750    2.3  36.1   345    3    2   6.9   3.8    9.0  48.2    -4.5     79  0.4
  6500    2.9  37.2   345    3    1   6.9   3.8    8.8  47.8    -4.7     57  0.3
  6250    3.4  38.1   345    2    1   7.1   3.9    8.6  47.4    -5.0     34  0.2
  6000    3.9  39.0   345    1    1   6.2   3.4    8.3  47.0    -5.2     11  0.1
  5750    4.3  39.7   345    1    0   5.1   2.8    8.0  46.4    -5.5      M    M
  5500    4.6  40.3   345    1    0   4.6   2.5    7.7  45.8    -5.9      M    M
  5250    5.0  41.0   000    0    0   6.1   3.3    7.3  45.1    -6.3      M    M
  5000    5.5  41.9   000    0    0   9.5   5.2    7.2  44.9    -6.6      M    M

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

           03/28/2017 at 0900 MDT          |       03/28/2017 at 1200 MDT
                                           |
K index... +21.0  LI... +1.1               | K index... +21.1  LI... +1.6
CAPE... 0.0  CIN... -0.0                   | CAPE... +5.4  CIN... 0.0
                                           |
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 -56.7 -70.1  240  22 11   1.9   1.0 | -56.0 -68.8  240  17  9   1.4   0.8
 45000 -53.8 -64.8  240  23 12   2.0   1.1 | -54.0 -65.2  240  19 10   1.4   0.8
 40000 -53.2 -63.8  225  21 11   0.3   0.2 | -53.7 -64.7  230  15  8   0.1   0.0
 38000 -53.0 -63.4  215  22 12   0.5   0.3 | -53.6 -64.5  215  15  8   0.7   0.4
 36000 -52.7 -62.9  205  29 15   0.5   0.3 | -53.2 -63.8  200  21 11   0.7   0.4
 34000 -52.4 -62.3  200  36 19   1.7   1.0 | -52.8 -63.0  190  27 14   2.1   1.2
 32000 -50.0 -58.0  195  30 15   4.1   2.3 | -49.9 -57.8  180  23 12   5.0   2.7
 30000 -47.5 -53.5  185  24 12   4.8   2.6 | -46.9 -52.4  170  19 10   5.2   2.8
 29000 -45.8 -50.4  170  19 10   5.7   3.1 | -45.4 -49.7  155  16  8   5.3   2.9
 28000 -44.1 -47.4  145  16  8   5.7   3.1 | -43.8 -46.8  135  13  7   5.3   2.9
 27000 -42.4 -44.3  120  16  8   5.8   3.2 | -41.8 -43.2  105  13  7   4.9   2.7
 26000 -39.5 -39.1  100  15  8   9.6   5.3 | -39.2 -38.6  090  13  7   9.6   5.3
 25000 -36.6 -33.9  095  13  7   9.5   5.2 | -36.4 -33.5  080  15  8   9.6   5.3
 24000 -33.8 -28.8  080  11  5   9.7   5.3 | -33.5 -28.3  070  16  8   9.8   5.4
 23000 -31.2 -24.2  070   9  5   8.1   4.5 | -31.0 -23.8  055  16  8   7.8   4.3
 22000 -28.8 -19.8  060   8  4   8.2   4.5 | -28.7 -19.7  035  17  9   7.8   4.3
 21000 -26.4 -15.5  045   7  4   8.0   4.4 | -26.4 -15.5  020  18  9   7.8   4.3
 20000 -24.1 -11.4  025   6  3   7.4   4.1 | -24.1 -11.4  015  19 10   7.9   4.3
 19500 -23.0  -9.4  010   6  3   7.4   4.1 | -22.9  -9.2  015  19 10   7.9   4.3
 19000 -21.9  -7.4  360   6  3   7.5   4.1 | -21.7  -7.1  015  19 10   7.9   4.3
 18500 -20.8  -5.4  345   6  3   7.5   4.1 | -20.6  -5.1  010  19 10   7.9   4.3
 18000 -19.7  -3.5  340   7  4   7.7   4.2 | -19.4  -2.9  010  19 10   7.5   4.1
 17500 -18.6  -1.5  340   9  4   7.7   4.2 | -18.3  -0.9  010  19 10   7.6   4.2
 17000 -17.4   0.7  335  10  5   7.6   4.2 | -17.2   1.0  010  19 10   7.2   3.9
 16500 -16.3   2.7  335  12  6   7.5   4.1 | -16.2   2.8  010  19 10   7.1   3.9
 16000 -15.2   4.6  335  13  7   7.3   4.0 | -15.1   4.8  015  19 10   6.9   3.8
 15500 -14.2   6.4  340  15  8   6.5   3.6 | -14.2   6.4  015  19 10   6.4   3.5
 15000 -13.3   8.1  345  16  8   6.6   3.6 | -13.2   8.2  015  19 10   6.4   3.5
 14500 -12.3   9.9  345  17  9   6.3   3.5 | -12.3   9.9  010  19 10   6.6   3.6
 14000 -11.4  11.5  350  18  9   6.3   3.5 | -11.3  11.7  010  19 10   6.6   3.6
 13500 -10.4  13.3  350  18  9   6.8   3.7 |  -9.9  14.2  010  19 10   6.6   3.6
 13000  -8.9  16.0  355  17  9   6.7   3.7 |  -8.9  16.0  010  18  9   6.6   3.6
 12500  -8.0  17.6  355  16  8   6.5   3.5 |  -8.0  17.6  010  18  9   6.5   3.6
 12000  -7.1  19.2  360  15  8   6.5   3.6 |  -7.0  19.4  010  17  9   6.1   3.3
 11500  -6.1  21.0  360  14  7   6.6   3.6 |  -6.3  20.7  010  15  8   4.1   2.2
 11000  -5.2  22.6  005  14  7   6.3   3.5 |  -5.7  21.7  005  12  6   4.4   2.4
 10500  -4.4  24.1  010  13  7   5.1   2.8 |  -5.0  23.0  005  11  5   4.9   2.7
 10250  -4.0  24.8  015  13  7   5.8   3.2 |  -4.7  23.5  005  10  5   5.3   2.9
 10000  -3.5  25.7  020  13  7   6.4   3.5 |  -4.3  24.3  010   9  5   6.3   3.5
  9750  -3.1  26.4  020  14  7   5.8   3.2 |  -3.8  25.2  005  10  5   6.6   3.6
  9500  -2.7  27.1  020  14  7   5.5   3.0 |  -3.3  26.1  005  11  6   6.4   3.5
  9250  -2.3  27.9  020  15  7   5.5   3.0 |  -2.9  26.8  005  13  7   6.6   3.6
  9000  -1.9  28.6  020  15  8   5.5   3.0 |  -2.3  27.9  005  14  7   7.9   4.3
  8750  -1.5  29.3  020  17  9   5.7   3.2 |  -1.7  28.9  005  13  7   8.5   4.7
  8500  -1.1  30.0  015  17  9   5.7   3.1 |  -1.1  30.0  005  13  7   8.2   4.5
  8250  -0.6  30.9  015  18 10   6.0   3.3 |  -0.5  31.1  005  13  7   8.7   4.7
  8000  -0.2  31.6  015  18  9   6.2   3.4 |   0.2  32.4  005  13  7   9.6   5.3
  7750   0.2  32.4  010  16  8   5.4   3.0 |   0.9  33.6  005  13  7   9.8   5.4
  7500   0.6  33.1  005  13  7   5.2   2.8 |   1.6  34.9  005  12  6   9.6   5.2
  7250   1.0  33.8  360  11  6   5.0   2.7 |   2.3  36.1  005  12  6  10.0   5.5
  7000   1.3  34.3  355   9  5   4.9   2.7 |   3.1  37.6  005  12  6  10.3   5.6
  6750   1.7  35.1  340   8  4   5.4   2.9 |   3.9  39.0  005  12  6   9.5   5.2
  6500   2.1  35.8  320   7  3   6.3   3.5 |   4.6  40.3  005  11  6   9.8   5.4
  6250   2.6  36.7  310   6  3   8.3   4.5 |   5.3  41.5  005  11  6  11.1   6.1
  6000   3.3  37.9  305   6  3   9.3   5.1 |   6.2  43.2  005  10  5  11.6   6.4
  5750   4.0  39.2  300   6  3  10.2   5.6 |   7.1  44.8  005  10  5  11.7   6.4
  5500   4.7  40.5  300   5  3   9.3   5.1 |   7.9  46.2  005   9  5  12.5   6.9
  5250   5.3  41.5  305   5  3   5.7   3.1 |   8.9  48.0  360   9  5  13.5   7.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/28/2017 at 1500 MDT          |       03/28/2017 at 1800 MDT
                                           |
K index... +23.5  LI... +1.2               | K index... +22.3  LI... +1.0
CAPE... +2.5  CIN... -0.1                  | CAPE... +1.7  CIN... -5.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -56.6 -69.9  230  15  8   1.9   1.1 | -56.9 -70.4  245  15  8   1.6   0.9
 45000 -53.8 -64.8  230  17  9   2.1   1.1 | -54.4 -65.9  240  15  8   1.7   1.0
 40000 -53.6 -64.5  225   8  4  -0.1  -0.0 | -54.4 -65.9  270   4  2  -0.1  -0.0
 38000 -53.6 -64.5  210   6  3   0.4   0.2 | -54.2 -65.6  340   3  1   1.0   0.5
 36000 -53.3 -63.9  190   8  4   0.4   0.2 | -53.6 -64.5  010   4  2   1.0   0.5
 34000 -53.0 -63.4  180  10  5   1.8   1.0 | -53.0 -63.4  025   6  3   1.8   1.0
 32000 -50.7 -59.3  150   7  4   4.0   2.2 | -51.2 -60.2  045   9  5   3.1   1.7
 30000 -48.3 -54.9  105   7  4   5.5   3.0 | -49.3 -56.7  055  13  7   6.1   3.3
 29000 -46.2 -51.2  075   8  4   7.1   3.9 | -46.8 -52.2  045  13  7   8.4   4.6
 28000 -44.1 -47.4  055  11  6   7.1   3.9 | -44.3 -47.7  040  14  7   8.4   4.6
 27000 -41.4 -42.5  040  15  8   7.1   3.9 | -41.2 -42.2  030  15  8   8.4   4.6
 26000 -38.8 -37.8  035  16  8   9.4   5.2 | -38.5 -37.3  025  15  8   9.0   4.9
 25000 -36.0 -32.8  025  17  9   9.4   5.2 | -35.8 -32.4  020  16  8   9.0   4.9
 24000 -33.2 -27.8  020  18  9   9.5   5.2 | -33.1 -27.6  015  17  9   9.1   5.0
 23000 -30.6 -23.1  025  17  9   8.3   4.6 | -30.6 -23.1  015  18  9   8.3   4.6
 22000 -28.1 -18.6  030  15  8   8.3   4.6 | -28.1 -18.6  015  18  9   8.3   4.6
 21000 -25.6 -14.1  035  14  7   8.1   4.5 | -25.7 -14.3  015  18  9   8.2   4.5
 20000 -23.4 -10.1  030  15  8   7.5   4.1 | -23.3  -9.9  015  19 10   7.9   4.3
 19500 -22.3  -8.1  030  16  8   7.5   4.1 | -22.2  -8.0  015  19 10   7.9   4.3
 19000 -21.1  -6.0  025  17  9   7.6   4.1 | -21.0  -5.8  015  20 10   7.9   4.3
 18500 -20.0  -4.0  025  19 10   7.5   4.1 | -19.8  -3.6  015  20 10   7.7   4.2
 18000 -19.0  -2.2  025  20 10   6.5   3.5 | -18.8  -1.8  015  21 11   6.3   3.5
 17500 -18.1  -0.6  025  21 11   6.5   3.6 | -17.9  -0.2  015  23 12   6.4   3.5
 17000 -17.1   1.2  025  22 11   7.2   3.9 | -16.9   1.6  015  24 12   6.9   3.8
 16500 -16.0   3.2  025  23 12   7.4   4.0 | -15.9   3.4  015  25 13   7.0   3.8
 16000 -14.9   5.2  020  24 12   7.4   4.1 | -14.9   5.2  015  26 13   6.8   3.7
 15500 -13.8   7.2  020  24 12   7.4   4.1 | -13.9   7.0  015  26 13   6.5   3.6
 15000 -12.7   9.1  020  24 12   7.4   4.1 | -13.0   8.6  015  26 13   6.5   3.6
 14500 -11.7  10.9  020  24 12   6.8   3.7 | -12.0  10.4  015  26 13   6.8   3.7
 14000 -10.7  12.7  020  24 12   6.9   3.8 | -11.0  12.2  015  26 13   6.8   3.7
 13500  -9.2  15.4  020  24 12   6.6   3.6 | -10.0  14.0  015  26 13   6.7   3.7
 13000  -8.3  17.1  020  24 12   6.3   3.5 |  -8.6  16.5  020  26 13   6.7   3.7
 12500  -7.5  18.5  020  24 12   5.5   3.0 |  -7.6  18.3  020  27 14   6.5   3.6
 12000  -6.7  19.9  020  24 12   5.6   3.1 |  -6.7  19.9  020  27 14   6.7   3.7
 11500  -5.8  21.6  020  24 12   5.7   3.1 |  -5.6  21.9  025  28 14   7.1   3.9
 11000  -5.0  23.0  025  24 12   5.6   3.1 |  -4.6  23.7  025  29 15   6.8   3.7
 10500  -4.2  24.4  025  25 13   5.0   2.7 |  -3.7  25.3  025  31 16   5.7   3.1
 10250  -3.8  25.2  025  25 13   6.7   3.7 |  -3.2  26.2  025  32 16   7.6   4.2
 10000  -3.3  26.1  025  25 13   7.7   4.2 |  -2.6  27.3  025  32 17   8.2   4.5
  9750  -2.8  27.0  025  26 13   5.9   3.3 |  -2.1  28.2  025  33 17   6.6   3.6
  9500  -2.4  27.7  025  27 14   5.6   3.0 |  -1.6  29.1  025  35 18   6.7   3.7
  9250  -2.0  28.4  025  27 14   6.0   3.3 |  -1.1  30.0  025  36 18   7.0   3.8
  9000  -1.5  29.3  020  28 14   6.1   3.3 |  -0.6  30.9  020  36 18   7.5   4.1
  8750  -1.1  30.0  020  27 14   5.8   3.2 |  -0.0  32.0  020  35 18   7.6   4.2
  8500  -0.7  30.7  015  26 13   5.6   3.1 |   0.5  32.9  020  33 17   7.3   4.0
  8250  -0.3  31.5  010  25 13   6.5   3.6 |   1.1  34.0  015  32 17   8.6   4.7
  8000   0.3  32.5  010  24 12   7.8   4.3 |   1.8  35.2  015  31 16   9.8   5.4
  7750   0.8  33.4  010  22 11   7.4   4.0 |   2.4  36.3  015  29 15   8.8   4.8
  7500   1.3  34.3  010  20 10   6.3   3.5 |   3.1  37.6  015  27 14   8.0   4.4
  7250   1.8  35.2  005  18  9   8.6   4.7 |   3.7  38.7  010  26 13   9.7   5.3
  7000   2.6  36.7  005  17  9  10.4   5.7 |   4.5  40.1  010  24 12  10.7   5.9
  6750   3.3  37.9  005  15  8   8.7   4.8 |   5.2  41.4  010  23 12   8.8   4.8
  6500   3.9  39.0  005  14  7   8.9   4.9 |   5.8  42.4  010  21 11   8.9   4.9
  6250   4.6  40.3  005  13  6  10.4   5.7 |   6.5  43.7  010  20 10  10.2   5.6
  6000   5.4  41.7  005  12  6  10.8   5.9 |   7.3  45.1  010  18  9  10.5   5.8
  5750   6.2  43.2  005  11  5  10.5   5.8 |   8.1  46.6  010  16  8  10.2   5.6
  5500   7.0  44.6  005   9  5   9.9   5.4 |   8.8  47.8  010  13  7   7.4   4.1
  5250   7.6  45.7  360  10  5   8.8   4.8 |   9.1  48.4  005  13  7   2.9   1.6
  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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