Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 201245
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0544 MST Tuesday, February 20, 2018

This forecast is for Tuesday, February 20, 2018:

If the trigger temperature of 27.7 F/-2.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 254 ft/min (1.3 m/s)
   Maximum height of thermals.................. 12798 ft MSL (7959 ft AGL)

Forecast maximum temperature................... 33.0 F/1.0 C
Time of trigger temperature.................... 1045 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................. 8482 ft MSL (3642 ft AGL)
Thermal soaring outlook for Wednesday 02/21.... Poor

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

Remarks...

Sunrise/Sunset.................... 06:58:58 / 17:55:52 MST
Total possible sunshine........... 10 hr 56 min 55 sec (656 min 55 sec)
Altitude of sun at 12:27:41 MST... 40.19 degrees

Upper air data from rawinsonde observation taken on 02/20/2018 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 9451 ft MSL (4612 ft AGL)
Lifted condensation level....... 10545 ft MSL (5706 ft AGL)
Lifted index.................... +6.6
K index......................... +3.9

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  -56.6 -69.9   230   98   50   5.5   3.0  111.8 233.3    62.6      M    M
 45000  -51.3 -60.3   230  107   55  -3.5  -1.9   94.7 202.4    56.8      M    M
 40000  -47.9 -54.2   225   94   48   2.7   1.5   76.4 169.6    48.9      M    M
 38000  -46.3 -51.3   225   90   47  -4.5  -2.5   70.1 158.2    46.0      M    M
 36000  -46.5 -51.7   230   80   41  -0.5  -0.3   61.1 142.0    41.1      M    M
 34000  -45.1 -49.2   230   89   46  -1.0  -0.5   54.6 130.2    37.6      M    M
 32000  -46.1 -51.0   230   99   51   3.8   2.1   44.7 112.5    31.6      M    M
 30000  -44.6 -48.3   230  108   55   2.4   1.3   37.9 100.1    27.4      M    M
 29000  -44.3 -47.7   230  105   54  -1.5  -0.8   34.4  93.9    25.2      M    M
 28000  -44.6 -48.3   230  107   55  -1.3  -0.7   30.0  86.1    22.2      M    M
 27000  -44.4 -47.9   230  107   55   1.6   0.9   26.6  79.8    19.9      M    M
 26000  -43.9 -47.0   230   98   51   1.6   0.9   23.3  74.0    17.6      M    M
 25000  -43.2 -45.8   230   89   46   4.6   2.5   20.5  68.8    15.6      M    M
 24000  -42.7 -44.9   230   75   39  -4.2  -2.3   17.5  63.4    13.4      M    M
 23000  -43.3 -45.9   230   62   32   3.0   1.7   13.0  55.4    10.0      M    M
 22000  -43.1 -45.6   230   52   27  -2.9  -1.6    9.6  49.3     7.4      M    M
 21000  -41.8 -43.2   230   49   25   6.1   3.4    7.6  45.7     5.8      M    M
 20000  -40.3 -40.5   230   45   23   5.8   3.2    6.0  42.8     4.5      M    M
 19500  -39.7 -39.5   225   40   21  -5.6  -3.1    4.9  40.8     3.6      M    M
 19000  -39.8 -39.6   220   35   18   8.0   4.4    3.0  37.5     2.1      M    M
 18500  -38.8 -37.8   220   34   17   7.6   4.2    2.5  36.6     1.7      M    M
 18000  -37.5 -35.5   225   34   17   8.8   4.8    2.3  36.2     1.5      M    M
 17500  -36.1 -33.0   225   34   17   9.8   5.4    2.3  36.2     1.5      M    M
 17000  -34.7 -30.5   225   32   16   9.1   5.0    2.2  35.9     1.4      M    M
 16500  -32.7 -26.9   230   29   15   8.9   4.9    2.0  35.6     1.2      M    M
 16000  -31.4 -24.5   230   27   14   8.8   4.9    1.9  35.4     1.1      M    M
 15500  -30.1 -22.2   235   24   13   8.8   4.9    1.7  35.1     1.0      M    M
 15000  -28.8 -19.8   240   23   12   8.8   4.8    1.6  34.8     0.8      M    M
 14500  -27.5 -17.5   250   21   11   8.0   4.4    1.3  34.4     0.6      M    M
 14000  -26.3 -15.3   255   20   10   8.5   4.7    1.1  34.0     0.4      M    M
 13500  -25.0 -13.0   260   19   10   8.5   4.7    0.9  33.6     0.2      M    M
 13000  -23.8 -10.8   260   19   10   8.7   4.8    0.7  33.2     0.0      M    M
 12500  -22.4  -8.3   265   18    9   9.5   5.2    0.7  33.2    -0.0    614  3.1
 12000  -21.4  -6.5   265   18    9   4.9   2.7    0.2  32.3    -0.5    570  2.9
 11500  -20.6  -5.1   265   16    8   5.0   2.8   -0.6  31.0    -1.2    531  2.7
 11000  -19.7  -3.5   270   15    7   8.0   4.4   -1.1  30.0    -1.7    489  2.5
 10500  -18.5  -1.3   270   13    7   8.1   4.4   -1.4  29.5    -2.0    438  2.2
 10250  -17.9  -0.2   270   12    6   8.1   4.4   -1.5  29.3    -2.1    413  2.1
 10000  -17.3   0.9   270   11    6   8.1   4.4   -1.6  29.0    -2.3    387  2.0
  9750  -16.7   1.9   275   10    5   8.1   4.5   -1.8  28.8    -2.4    362  1.8
  9500  -16.0   3.2   280    9    5   8.3   4.6   -1.9  28.6    -2.5    336  1.7
  9250  -15.4   4.3   285    8    4   8.5   4.7   -2.0  28.4    -2.6    310  1.6
  9000  -14.8   5.4   300    6    3   8.3   4.6   -2.1  28.3    -2.7    284  1.4
  8750  -14.2   6.4   295    6    3   8.7   4.8   -2.2  28.1    -2.8    258  1.3
  8500  -13.5   7.7   285    5    3   7.3   4.0   -2.3  27.9    -2.9    232  1.2
  8250  -13.1   8.4   280    5    3   4.6   2.5   -2.6  27.3    -3.3    212  1.1
  8000  -12.8   9.0   270    5    3   3.6   2.0   -3.0  26.5    -3.7    195  1.0
  7750  -12.5   9.5   280    4    2   5.3   2.9   -3.5  25.7    -4.2    179  0.9
  7500  -12.1  10.2   300    4    2   6.9   3.8   -3.7  25.3    -4.4    158  0.8
  7250  -11.5  11.3   325    3    2   6.8   3.7   -4.0  24.9    -4.7    135  0.7
  7000  -11.0  12.2   345    4    2   6.8   3.7   -4.2  24.5    -4.9    112  0.6
  6750  -10.5  13.1   360    5    2   6.8   3.7   -4.4  24.1    -5.1     90  0.5
  6500  -10.0  14.0   010    6    3   6.8   3.7   -4.6  23.6    -5.4     67  0.3
  6250   -9.5  14.9   020    7    3   6.9   3.8   -4.9  23.2    -5.6     45  0.2
  6000   -9.0  15.8   025    8    4   6.6   3.6   -5.1  22.8    -5.8     22  0.1
  5750   -8.6  16.5   020    7    3   5.5   3.0   -5.4  22.3    -6.1      1  0.0
  5500   -8.2  17.2   010    5    3   4.5   2.5   -5.7  21.7    -6.5      M    M
  5250   -7.9  17.8   345    4    2   6.3   3.4   -6.1  21.0    -6.9      M    M
  5000   -7.3  18.9   310    3    2  10.8   5.9   -6.2  20.9    -7.1      M    M

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

           02/20/2018 at 0800 MST          |       02/20/2018 at 1100 MST
                                           |
K index... +1.5  LI... +0.8                | K index... -3.0  LI... +1.8
CAPE... 0.0  CIN... -3.5                   | CAPE... +0.2  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 -57.1 -70.8  235  95 49   3.7   2.0 | -56.6 -69.9  235  97 50   3.4   1.9
 45000 -51.3 -60.3  235  99 51   3.7   2.0 | -51.3 -60.3  230 102 53   3.4   1.9
 40000 -48.0 -54.4  235  90 47   1.9   1.1 | -48.3 -54.9  230  95 49   1.6   0.9
 38000 -46.8 -52.2  235  86 44   1.9   1.0 | -47.4 -53.3  230  92 47   1.6   0.9
 36000 -46.6 -51.9  235  86 44   0.2   0.1 | -47.1 -52.8  230  90 46   0.3   0.2
 34000 -46.5 -51.7  235  87 45   0.2   0.1 | -46.9 -52.4  230  88 45   0.3   0.2
 32000 -46.1 -51.0  235  91 47   1.2   0.7 | -46.8 -52.2  230  89 46   0.2   0.1
 30000 -45.3 -49.5  235  98 51   1.2   0.7 | -46.6 -51.9  230  92 47   0.2   0.1
 29000 -44.9 -48.8  235 101 52   2.5   1.4 | -46.5 -51.7  230  93 48   2.3   1.3
 28000 -44.0 -47.2  235  99 51   3.0   1.6 | -45.6 -50.1  230  89 46   2.8   1.5
 27000 -43.1 -45.6  235  96 50   3.0   1.6 | -44.8 -48.6  230  84 43   2.8   1.5
 26000 -42.2 -44.0  235  94 48   3.1   1.7 | -44.0 -47.2  230  80 41   2.7   1.5
 25000 -41.7 -43.1  235  87 45   1.0   0.6 | -43.1 -45.6  235  73 38   3.0   1.6
 24000 -41.4 -42.5  235  78 40   1.0   0.6 | -42.2 -44.0  235  66 34   3.0   1.6
 23000 -41.1 -42.0  235  69 35   1.1   0.6 | -41.3 -42.3  235  59 30   3.0   1.6
 22000 -41.0 -41.8  235  58 30  -0.1  -0.1 | -40.5 -40.9  240  52 27   2.6   1.4
 21000 -41.0 -41.8  240  46 24  -0.1  -0.1 | -39.7 -39.5  240  46 24   2.6   1.4
 20000 -41.1 -42.0  240  34 18   2.3   1.3 | -39.0 -38.2  240  40 21   3.1   1.7
 19500 -40.2 -40.4  245  32 17   6.3   3.4 | -38.4 -37.1  240  37 19   3.5   1.9
 19000 -39.3 -38.7  245  31 16   6.3   3.5 | -37.9 -36.2  240  34 18   3.6   2.0
 18500 -38.3 -36.9  245  29 15   6.3   3.5 | -37.4 -35.3  245  31 16   3.6   2.0
 18000 -37.4 -35.3  245  27 14   6.3   3.5 | -36.8 -34.2  245  29 15   3.4   1.9
 17500 -36.4 -33.5  245  25 13   8.1   4.4 | -36.1 -33.0  245  26 13   7.3   4.0
 17000 -35.1 -31.2  245  24 13   9.1   5.0 | -34.9 -30.8  245  25 13   8.3   4.6
 16500 -33.7 -28.7  245  24 12   8.9   4.9 | -33.6 -28.5  245  24 12   8.4   4.6
 16000 -32.4 -26.3  245  23 12   8.1   4.5 | -32.4 -26.3  245  22 11   8.4   4.6
 15500 -31.2 -24.2  250  22 11   8.1   4.5 | -31.1 -24.0  250  21 11   8.3   4.5
 15000 -30.0 -22.0  250  21 11   8.1   4.4 | -30.0 -22.0  250  20 10   7.3   4.0
 14500 -28.8 -19.8  250  20 10   8.0   4.4 | -28.3 -18.9  250  18  9   8.1   4.5
 14000 -26.9 -16.4  250  18 10   8.9   4.9 | -27.0 -16.6  250  17  9   8.4   4.6
 13500 -25.5 -13.9  250  18  9   9.0   5.0 | -25.7 -14.3  250  17  9   8.5   4.7
 13000 -24.1 -11.4  250  17  9   9.1   5.0 | -24.4 -11.9  255  17  9   8.6   4.7
 12500 -22.8  -9.0  250  16  8   8.8   4.8 | -23.1  -9.6  255  16  8   8.2   4.5
 12000 -21.5  -6.7  250  14  7   8.5   4.6 | -21.9  -7.4  255  16  8   8.0   4.4
 11500 -20.3  -4.5  250  13  7   7.8   4.3 | -20.7  -5.3  255  16  8   8.5   4.7
 11000 -19.2  -2.6  250  12  6   7.5   4.1 | -19.4  -2.9  255  15  8   8.8   4.8
 10500 -18.2  -0.8  255  10  5   5.9   3.3 | -18.3  -0.9  255  14  7   7.1   3.9
 10250 -17.8  -0.0  260  10  5   5.0   2.8 | -17.8  -0.0  255  14  7   6.3   3.5
 10000 -17.4   0.7  265   9  5   6.4   3.5 | -17.3   0.9  255  13  7   8.7   4.8
  9750 -16.8   1.8  265   8  4   7.7   4.2 | -16.5   2.3  255  12  6   8.9   4.9
  9500 -16.3   2.7  270   8  4   6.9   3.8 | -16.0   3.2  260  11  6   6.5   3.6
  9250 -15.8   3.6  275   8  4   6.6   3.6 | -15.5   4.1  260   9  5   7.4   4.1
  9000 -15.3   4.5  280   7  4   6.6   3.6 | -15.0   5.0  265   8  4   6.4   3.5
  8750 -14.8   5.4  285   7  3   6.4   3.5 | -14.6   5.7  270   7  4   6.2   3.4
  8500 -14.3   6.3  290   6  3   6.6   3.6 | -14.1   6.6  275   6  3   6.9   3.8
  8250 -13.8   7.2  290   6  3   6.3   3.5 | -13.6   7.5  275   6  3   6.7   3.7
  8000 -13.3   8.1  295   5  3   7.4   4.1 | -13.1   8.4  285   5  3   7.3   4.0
  7750 -12.8   9.0  295   5  3   7.4   4.0 | -12.5   9.5  285   5  2   8.3   4.6
  7500 -12.3   9.9  295   4  2   6.3   3.5 | -11.9  10.6  285   5  2   8.4   4.6
  7250 -11.8  10.8  300   3  2   6.4   3.5 | -11.2  11.8  285   4  2   9.1   5.0
  7000 -11.3  11.7  310   2  1   6.0   3.3 | -10.5  13.1  285   4  2  10.2   5.6
  6750 -10.9  12.4  330   2  1   5.0   2.7 |  -9.7  14.5  285   4  2   9.9   5.4
  6500 -10.6  12.9  360   2  1   4.3   2.4 |  -9.0  15.8  285   4  2  10.0   5.5
  6250 -10.2  13.6  020   2  1   6.2   3.4 |  -8.2  17.2  285   4  2  11.1   6.1
  6000  -9.7  14.5  020   2  1   7.3   4.0 |  -7.4  18.7  285   4  2  11.3   6.2
  5750  -9.1  15.6  020   2  1   9.0   4.9 |  -6.5  20.3  285   4  2  10.7   5.9
  5500  -8.4  16.9  020   2  1   8.6   4.7 |  -5.7  21.7  285   4  2  12.2   6.7
  5250  -8.0  17.6  020   2  1   3.8   2.1 |  -4.7  23.5  285   4  2  15.1   8.3
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/20/2018 at 1400 MST          |       02/20/2018 at 1700 MST
                                           |
K index... -7.4  LI... +2.0                | K index... -7.4  LI... +3.0
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  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 -56.5 -69.7  235  97 50   2.9   1.6 | -56.5 -69.7  235  93 48   2.6   1.4
 45000 -51.8 -61.2  235 103 53   2.9   1.6 | -52.4 -62.3  235  97 50   2.6   1.4
 40000 -49.1 -56.4  235  95 49   1.6   0.9 | -49.8 -57.6  235  87 45   1.6   0.9
 38000 -48.1 -54.6  235  91 47   1.5   0.8 | -48.9 -56.0  240  83 43   1.5   0.8
 36000 -47.5 -53.5  235  89 46   1.1   0.6 | -48.2 -54.8  235  79 41   1.1   0.6
 34000 -46.8 -52.2  235  88 45   1.1   0.6 | -47.5 -53.5  235  76 39   1.1   0.6
 32000 -46.4 -51.5  230  86 44   0.0   0.0 | -47.0 -52.6  235  72 37   0.7   0.4
 30000 -46.4 -51.5  230  85 44   0.0   0.0 | -46.5 -51.7  235  68 35   0.7   0.4
 29000 -46.3 -51.3  230  84 43   1.5   0.8 | -46.2 -51.2  235  66 34   1.6   0.9
 28000 -45.8 -50.4  230  79 41   1.6   0.9 | -45.8 -50.4  240  63 33   1.5   0.8
 27000 -45.4 -49.7  235  74 38   1.6   0.9 | -45.3 -49.5  240  60 31   1.5   0.8
 26000 -44.9 -48.8  235  70 36   1.3   0.7 | -44.9 -48.8  240  57 29   1.5   0.8
 25000 -43.8 -46.8  235  64 33   4.2   2.3 | -44.1 -47.4  240  53 27   2.7   1.5
 24000 -42.6 -44.7  235  59 30   4.2   2.3 | -43.3 -45.9  240  49 25   2.7   1.5
 23000 -41.3 -42.3  240  53 27   4.3   2.4 | -42.5 -44.5  245  45 23   2.8   1.5
 22000 -40.3 -40.5  240  48 25   3.1   1.7 | -41.0 -41.8  245  42 22   5.5   3.0
 21000 -39.3 -38.7  245  43 22   3.1   1.7 | -39.4 -38.9  250  40 20   5.5   3.0
 20000 -38.4 -37.1  245  39 20   3.7   2.1 | -37.8 -36.0  250  37 19   4.3   2.4
 19500 -37.8 -36.0  245  37 19   4.0   2.2 | -37.2 -35.0  250  36 18   4.1   2.3
 19000 -37.2 -35.0  245  35 18   4.1   2.2 | -36.5 -33.7  250  34 18   4.1   2.2
 18500 -36.6 -33.9  245  34 17   4.0   2.2 | -35.9 -32.6  250  33 17   4.1   2.2
 18000 -36.0 -32.8  245  32 16   3.9   2.1 | -35.3 -31.5  250  32 16   3.9   2.1
 17500 -35.3 -31.5  245  30 16   6.1   3.4 | -34.6 -30.3  250  31 16   6.0   3.3
 17000 -34.3 -29.7  245  29 15   6.5   3.5 | -33.7 -28.7  245  30 16   5.9   3.2
 16500 -33.3 -27.9  245  28 14   7.4   4.1 | -32.8 -27.0  245  30 15   7.3   4.0
 16000 -32.1 -25.8  245  27 14   8.2   4.5 | -31.6 -24.9  240  29 15   7.9   4.3
 15500 -30.9 -23.6  245  27 14   8.4   4.6 | -30.4 -22.7  240  29 15   8.6   4.7
 15000 -29.6 -21.3  245  26 13   8.8   4.8 | -29.0 -20.2  240  28 14   9.3   5.1
 14500 -27.6 -17.7  245  24 13   8.7   4.8 | -27.0 -16.6  240  27 14   8.9   4.9
 14000 -26.3 -15.3  245  24 12   8.7   4.8 | -25.7 -14.3  240  26 13   8.8   4.8
 13500 -25.0 -13.0  245  23 12   8.7   4.8 | -24.3 -11.7  240  26 13   8.7   4.8
 13000 -23.7 -10.7  245  22 11   8.7   4.8 | -23.0  -9.4  245  25 13   8.7   4.8
 12500 -22.4  -8.3  245  21 11   8.3   4.6 | -21.7  -7.1  245  24 13   8.7   4.7
 12000 -21.2  -6.2  250  20 10   8.2   4.5 | -20.4  -4.7  250  24 12   8.7   4.8
 11500 -19.9  -3.8  250  19 10   8.3   4.6 | -19.2  -2.6  250  23 12   8.0   4.4
 11000 -18.7  -1.7  255  18  9   8.5   4.7 | -18.0  -0.4  250  22 11   8.1   4.4
 10500 -17.5   0.5  255  18  9   7.3   4.0 | -16.8   1.8  255  21 11   7.5   4.1
 10250 -17.0   1.4  255  17  9   6.8   3.7 | -16.3   2.7  255  21 11   6.7   3.7
 10000 -16.4   2.5  260  17  9   8.8   4.9 | -15.7   3.7  255  20 10   9.9   5.4
  9750 -15.7   3.7  260  16  8   9.0   5.0 | -14.9   5.2  255  19 10   9.9   5.5
  9500 -15.1   4.8  260  15  8   7.1   3.9 | -14.3   6.3  260  18  9   6.8   3.7
  9250 -14.6   5.7  265  14  7   7.7   4.2 | -13.8   7.2  260  18  9   7.7   4.2
  9000 -14.0   6.8  265  13  7   7.4   4.1 | -13.2   8.2  260  17  9   7.3   4.0
  8750 -13.5   7.7  265  11  6   7.6   4.2 | -12.7   9.1  260  15  8   7.3   4.0
  8500 -12.9   8.8  270  10  5   7.9   4.3 | -12.1  10.2  265  13  7   7.5   4.1
  8250 -12.3   9.9  270   9  5   7.8   4.3 | -11.5  11.3  265  11  6   7.7   4.2
  8000 -11.7  10.9  270   8  4   9.7   5.3 | -10.9  12.4  270  10  5   8.7   4.8
  7750 -10.9  12.4  270   8  4  10.2   5.6 | -10.3  13.5  270   9  4   8.7   4.8
  7500 -10.2  13.6  270   8  4   8.9   4.9 |  -9.7  14.5  270   8  4   8.0   4.4
  7250  -9.5  14.9  270   8  4   9.9   5.4 |  -9.0  15.8  275   7  4   9.2   5.1
  7000  -8.8  16.2  270   8  4  10.7   5.9 |  -8.3  17.1  275   7  4  10.3   5.7
  6750  -8.0  17.6  270   8  4  10.0   5.5 |  -7.6  18.3  275   7  4   9.3   5.1
  6500  -7.2  19.0  270   8  4  10.0   5.5 |  -6.9  19.6  275   7  3   9.5   5.2
  6250  -6.5  20.3  270   8  4  11.2   6.1 |  -6.1  21.0  275   6  3  10.5   5.7
  6000  -5.6  21.9  270   7  4  11.3   6.2 |  -5.3  22.5  275   6  3  10.4   5.7
  5750  -4.8  23.4  270   7  4  11.0   6.0 |  -4.6  23.7  275   6  3   8.6   4.7
  5500  -3.9  25.0  270   7  4  12.6   6.9 |  -4.1  24.6  275   6  3   6.5   3.6
  5250  -2.9  26.8  270   7  4  14.9   8.2 |  -3.6  25.5  280   5  3   7.0   3.8
  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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