Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281250
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0550 MST Tuesday, February 28, 2017

This forecast is for Tuesday, February 28, 2017:

If the trigger temperature of 41.8 F/5.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9480 ft MSL (4641 ft AGL)

Forecast maximum temperature................... 44.0 F/7.1 C
Time of trigger temperature.................... 1100 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................. 7826 ft MSL (2987 ft AGL)
Thermal soaring outlook for Wednesday 03/01.... Poor

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

Remarks...

Sunrise/Sunset.................... 06:47:32 / 18:04:53 MST
Total possible sunshine........... 11 hr 17 min 20 sec (677 min 20 sec)
Altitude of sun at 12:26:27 MST... 43.24 degrees

Upper air data from rawinsonde observation taken on 02/28/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 9674 ft MSL (4835 ft AGL)
Lifted condensation level....... 9603 ft MSL (4764 ft AGL)
Lifted index.................... +5.6
K index......................... +15.8

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  -55.7 -68.3   250   55   28   0.4   0.2  113.1 235.6    59.9      M    M
 45000  -53.1 -63.6   250   73   38   2.0   1.1   91.5 196.6    51.2      M    M
 40000  -54.5 -66.1   245   77   40   0.7   0.4   65.7 150.2    38.1      M    M
 38000  -55.7 -68.3   245   81   42   1.5   0.8   54.9 130.9    32.0      M    M
 36000  -57.8 -72.0   245   83   43  -0.5  -0.3   43.1 109.6    24.8      M    M
 34000  -56.7 -70.1   240   86   44  -1.0  -0.6   36.2  97.1    20.7      M    M
 32000  -57.5 -71.5   235  104   54   8.9   4.9   25.8  78.4    13.8      M    M
 30000  -51.9 -61.4   230   97   50   9.3   5.1   25.4  77.8    13.9      M    M
 29000  -49.5 -57.1   230   96   50   7.8   4.3   24.7  76.5    13.5      M    M
 28000  -47.2 -53.0   230   92   47   7.7   4.2   23.9  75.0    13.1      M    M
 27000  -44.7 -48.5   230   87   45   9.1   5.0   23.4  74.2    12.9      M    M
 26000  -42.0 -43.6   230   83   43   8.5   4.7   23.1  73.6    12.8      M    M
 25000  -39.4 -38.9   230   78   40   8.4   4.6   22.7  72.9    12.7      M    M
 24000  -37.0 -34.6   230   80   41   8.2   4.5   22.1  71.9    12.3      M    M
 23000  -34.5 -30.1   230   76   39   8.3   4.6   21.6  70.8    12.0      M    M
 22000  -32.0 -25.6   225   68   35   8.5   4.6   21.0  69.8    11.7      M    M
 21000  -29.9 -21.8   225   60   31   6.2   3.4   20.0  68.0    11.0      M    M
 20000  -28.1 -18.6   220   53   27   6.2   3.4   18.7  65.7    10.1      M    M
 19500  -27.2 -17.0   220   50   26   6.0   3.3   18.1  64.6     9.6      M    M
 19000  -26.1 -15.0   220   48   24   7.9   4.3   17.6  63.7     9.2      M    M
 18500  -25.0 -13.0   230   46   24   7.7   4.2   17.2  63.0     8.9      M    M
 18000  -23.8 -10.8   235   47   24   7.7   4.2   16.9  62.4     8.7      M    M
 17500  -22.2  -8.0   250   50   26   5.1   2.8   16.2  61.2     8.2      M    M
 17000  -21.6  -6.9   255   51   26   4.0   2.2   15.2  59.4     7.3      M    M
 16500  -21.1  -6.0   260   48   25   4.0   2.2   14.2  57.6     6.5      M    M
 16000  -20.5  -4.9   260   44   23   4.3   2.4   13.2  55.8     5.7      M    M
 15500  -19.5  -3.1   270   39   20   7.6   4.2   12.7  54.8     5.2      M    M
 15000  -18.5  -1.3   275   34   18   7.4   4.0   12.3  54.2     4.9      M    M
 14500  -17.4   0.7   265   31   16   7.4   4.0   11.9  53.5     4.5      M    M
 14000  -16.3   2.7   260   29   15   7.4   4.0   11.6  52.8     4.2      M    M
 13500  -15.2   4.6   260   27   14   7.4   4.1   11.1  52.1     3.8      M    M
 13000  -14.1   6.6   260   24   13   7.4   4.1   10.7  51.3     3.5      M    M
 12500  -13.0   8.6   260   22   11   7.4   4.1   10.4  50.7     3.1      M    M
 12000  -11.9  10.6   260   20   10   7.4   4.1   10.0  50.1     2.8      M    M
 11500  -10.9  12.4   260   17    9   7.4   4.1    9.6  49.3     2.4      M    M
 11000   -9.8  14.4   255   15    8   7.4   4.1    9.3  48.7     2.0      M    M
 10500   -8.7  16.3   255   11    6   6.6   3.6    8.9  47.9     1.6      M    M
 10250   -8.3  17.1   255    9    5   4.6   2.5    8.5  47.3     1.3      M    M
 10000   -8.0  17.6   255    7    4   4.3   2.3    8.1  46.5     0.9      M    M
  9750   -7.7  18.1   270   12    6   4.3   2.3    7.6  45.8     0.5      M    M
  9500   -7.4  18.7   275   13    7   4.0   2.2    7.2  45.0     0.1      M    M
  9250   -7.1  19.2   275   10    5   3.9   2.1    6.7  44.1    -0.4    293  1.5
  9000   -6.8  19.8   280    7    4   3.9   2.1    6.3  43.3    -0.8    277  1.4
  8750   -6.5  20.3   290    7    4   3.9   2.1    5.8  42.5    -1.3    261  1.3
  8500   -6.2  20.8   305    8    4   3.9   2.1    5.4  41.7    -1.7    245  1.2
  8250   -5.9  21.4   310    9    5   3.9   2.1    4.9  40.9    -2.2    229  1.2
  8000   -5.6  21.9   320   11    6   3.9   2.1    4.5  40.1    -2.6    213  1.1
  7750   -5.4  22.3   320   11    6   3.9   2.1    4.0  39.2    -3.1    197  1.0
  7500   -5.1  22.8   320   11    5   3.9   2.1    3.6  38.4    -3.5    181  0.9
  7250   -4.8  23.4   315   10    5   3.9   2.1    3.1  37.6    -4.0    165  0.8
  7000   -4.5  23.9   315   10    5   3.9   2.2    2.7  36.8    -4.4    149  0.8
  6750   -4.2  24.4   315    8    4   3.9   2.1    2.2  36.0    -4.9    134  0.7
  6500   -3.9  25.0   315    5    3   3.9   2.2    1.8  35.2    -5.4    118  0.6
  6250   -3.6  25.5   320    2    1   3.9   2.1    1.3  34.4    -5.8    102  0.5
  6000   -3.4  25.9   000    0    0   4.0   2.2    0.9  33.6    -6.3     86  0.4
  5750   -3.1  26.4   125    1    0   3.5   1.9    0.4  32.8    -6.7     70  0.4
  5500   -2.8  27.0   125    1    0   5.3   2.9   -0.0  32.0    -7.2     54  0.3
  5250   -2.3  27.9   000    0    0   8.1   4.4   -0.2  31.6    -7.4     31  0.2
  5000   -1.7  28.9   000    0    0   9.2   5.0   -0.3  31.5    -7.6      5  0.0

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

           02/28/2017 at 0800 MST          |       02/28/2017 at 1100 MST
                                           |
K index... +11.4  LI... +3.5               | K index... +10.3  LI... +2.5
CAPE... +0.8  CIN... -2.8                  | CAPE... 0.0  CIN... -0.1
                                           |
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 -54.8 -66.6  255  51 26   1.3   0.7 | -55.0 -67.0  250  50 26   1.3   0.7
 45000 -52.7 -62.9  255  62 32   1.3   0.7 | -53.0 -63.4  255  56 29   1.3   0.7
 40000 -52.9 -63.2  255  69 36  -0.5  -0.3 | -51.8 -61.2  260  61 31   0.7   0.4
 38000 -53.3 -63.9  255  72 37  -0.9  -0.5 | -51.4 -60.5  260  63 32   0.2   0.1
 36000 -54.5 -66.1  250  74 38  -2.2  -1.2 | -52.4 -62.3  260  65 33  -1.7  -0.9
 34000 -55.9 -68.6  245  77 39  -2.2  -1.2 | -53.4 -64.1  255  67 34  -1.7  -0.9
 32000 -55.2 -67.4  245  82 42   3.5   1.9 | -53.3 -63.9  250  68 35   1.7   0.9
 30000 -53.1 -63.6  240  89 46   3.5   1.9 | -52.2 -62.0  245  70 36   1.8   1.0
 29000 -51.1 -60.0  240  90 46   7.4   4.1 | -51.1 -60.0  240  72 37   6.4   3.5
 28000 -48.9 -56.0  235  86 44   7.5   4.1 | -49.1 -56.4  240  74 38   6.4   3.5
 27000 -46.6 -51.9  235  82 42   7.5   4.1 | -47.2 -53.0  240  76 39   6.4   3.5
 26000 -44.3 -47.7  235  78 40   9.2   5.0 | -45.3 -49.5  235  78 40   8.0   4.4
 25000 -41.4 -42.5  235  75 39   9.5   5.2 | -42.6 -44.7  240  79 41   8.8   4.8
 24000 -38.6 -37.5  235  72 37   9.5   5.2 | -40.0 -40.0  240  80 41   8.8   4.8
 23000 -35.8 -32.4  235  69 35   8.3   4.6 | -37.4 -35.3  240  80 41   7.1   3.9
 22000 -33.4 -28.1  240  68 35   8.0   4.4 | -35.6 -32.1  245  71 37   6.2   3.4
 21000 -31.1 -24.0  245  68 35   8.0   4.4 | -33.7 -28.7  250  63 33   6.2   3.4
 20000 -28.8 -19.8  245  66 34   6.5   3.6 | -31.8 -25.2  255  57 29   6.7   3.7
 19500 -27.8 -18.0  250  64 33   6.6   3.6 | -30.8 -23.4  260  54 28   6.7   3.7
 19000 -26.8 -16.2  250  62 32   6.6   3.6 | -29.8 -21.6  260  52 27   6.7   3.7
 18500 -25.8 -14.4  250  60 31   6.6   3.6 | -28.8 -19.8  260  49 25   6.7   3.7
 18000 -24.8 -12.6  255  58 30   6.5   3.6 | -27.8 -18.0  260  46 24   6.7   3.7
 17500 -24.1 -11.4  255  55 28   3.2   1.7 | -26.9 -16.4  260  43 22   5.7   3.1
 17000 -23.6 -10.5  260  50 26   3.4   1.9 | -26.0 -14.8  265  40 21   5.7   3.1
 16500 -23.1  -9.6  265  46 24   4.0   2.2 | -25.1 -13.2  265  38 19   6.5   3.6
 16000 -22.5  -8.5  265  41 21   4.1   2.3 | -24.1 -11.4  265  35 18   6.6   3.6
 15500 -21.9  -7.4  265  37 19   5.0   2.7 | -23.1  -9.6  265  32 17   6.9   3.8
 15000 -21.0  -5.8  265  33 17   5.9   3.2 | -22.1  -7.8  265  30 15   7.2   3.9
 14500 -20.1  -4.2  265  28 15   6.5   3.6 | -21.0  -5.8  260  28 14   7.6   4.1
 14000 -18.4  -1.1  265  25 13   8.2   4.5 | -19.2  -2.6  255  26 13   8.4   4.6
 13500 -17.2   1.0  260  24 12   8.4   4.6 | -18.0  -0.4  255  26 13   7.9   4.4
 13000 -16.0   3.2  260  24 12   8.5   4.7 | -16.8   1.8  260  25 13   7.9   4.3
 12500 -14.7   5.5  260  24 13   8.2   4.5 | -15.7   3.7  260  25 13   7.7   4.2
 12000 -13.6   7.5  260  24 12   8.0   4.4 | -14.6   5.7  265  23 12   7.7   4.2
 11500 -12.4   9.7  255  23 12   7.6   4.2 | -13.5   7.7  265  22 11   5.8   3.2
 11000 -11.3  11.7  260  22 11   7.5   4.1 | -12.7   9.1  270  20 11   5.5   3.0
 10500 -10.3  13.5  260  19 10   4.5   2.4 | -12.0  10.4  275  18 10   3.7   2.0
 10250 -10.1  13.8  260  17  9   3.7   2.1 | -11.8  10.8  280  17  9   3.2   1.8
 10000  -9.8  14.4  265  15  8   2.7   1.5 | -11.5  11.3  285  16  8   4.1   2.3
  9750  -9.7  14.5  265  13  7   1.5   0.8 | -11.2  11.8  290  15  8   5.0   2.8
  9500  -9.5  14.9  275  11  6   2.0   1.1 | -10.8  12.6  290  14  7   4.9   2.7
  9250  -9.4  15.1  285   8  4   2.5   1.4 | -10.5  13.1  295  14  7   4.9   2.7
  9000  -9.2  15.4  305   6  3   0.3   0.2 | -10.1  13.8  300  13  7   5.0   2.8
  8750  -9.2  15.4  330   5  3   2.3   1.3 |  -9.7  14.5  305  12  6   5.5   3.0
  8500  -8.8  16.2  350   6  3   6.3   3.5 |  -9.3  15.3  310  12  6   5.7   3.1
  8250  -8.4  16.9  005   8  4   4.5   2.4 |  -8.9  16.0  310  11  6   5.3   2.9
  8000  -8.0  17.6  015   9  5   8.0   4.4 |  -8.5  16.7  315  10  5   6.7   3.7
  7750  -7.3  18.9  015  10  5   9.3   5.1 |  -7.9  17.8  310  10  5   7.4   4.1
  7500  -6.8  19.8  020   9  5   7.1   3.9 |  -7.4  18.7  305   9  5   6.4   3.5
  7250  -6.2  20.8  020   9  5   7.7   4.2 |  -6.9  19.6  300   9  5   7.4   4.0
  7000  -5.7  21.7  020   9  4   6.8   3.7 |  -6.3  20.7  300   9  4   9.9   5.4
  6750  -5.2  22.6  015   8  4   6.5   3.6 |  -5.5  22.1  295   9  4  10.6   5.8
  6500  -4.7  23.5  005   7  3   6.6   3.6 |  -4.8  23.4  295   8  4   9.8   5.4
  6250  -4.2  24.4  355   6  3   7.4   4.1 |  -4.0  24.8  295   8  4  10.8   5.9
  6000  -3.6  25.5  350   6  3   8.6   4.7 |  -3.2  26.2  295   8  4  11.4   6.2
  5750  -3.0  26.6  345   5  3   9.4   5.2 |  -2.4  27.7  295   8  4  10.4   5.7
  5500  -2.3  27.9  345   5  2   8.7   4.8 |  -1.6  29.1  290   8  4  10.8   6.0
  5250  -1.8  28.8  345   5  3   4.9   2.7 |  -0.7  30.7  295   8  4  13.1   7.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/28/2017 at 1400 MST          |       02/28/2017 at 1700 MST
                                           |
K index... +5.7  LI... +2.9                | K index... +7.2  LI... +2.3
CAPE... +14.0  CIN... -0.0                 | CAPE... +12.7  CIN... -8.3
                                           |
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 -55.0 -67.0  255  49 25   1.3   0.7 | -54.7 -66.5  260  45 23   0.3   0.2
 45000 -53.0 -63.4  260  56 29   1.3   0.7 | -54.1 -65.4  270  53 27   0.3   0.2
 40000 -52.8 -63.0  270  58 30  -0.1  -0.1 | -54.5 -66.1  285  66 34  -0.4  -0.2
 38000 -52.9 -63.2  275  59 30  -0.1  -0.1 | -54.8 -66.6  285  71 37   0.1   0.1
 36000 -53.0 -63.4  280  62 32  -0.2  -0.1 | -54.3 -65.7  290  77 39   0.9   0.5
 34000 -53.1 -63.6  285  66 34  -0.2  -0.1 | -53.7 -64.7  290  82 42   0.9   0.5
 32000 -52.0 -61.6  285  67 34   3.1   1.7 | -51.9 -61.4  295  84 43   4.5   2.5
 30000 -49.9 -57.8  285  64 33   3.2   1.8 | -48.8 -55.8  295  85 44   4.5   2.5
 29000 -48.7 -55.7  285  63 32   5.2   2.9 | -47.4 -53.3  295  83 43   5.1   2.8
 28000 -47.1 -52.8  285  61 31   5.2   2.9 | -45.8 -50.4  295  79 41   5.1   2.8
 27000 -45.5 -49.9  280  59 30   5.2   2.9 | -44.3 -47.7  295  75 39   5.1   2.8
 26000 -44.0 -47.2  280  58 30   5.5   3.0 | -42.8 -45.0  295  72 37   5.8   3.2
 25000 -42.2 -44.0  275  57 29   5.7   3.1 | -41.0 -41.8  295  69 35   6.0   3.3
 24000 -40.5 -40.9  270  57 29   5.7   3.1 | -39.1 -38.4  290  66 34   6.0   3.3
 23000 -38.8 -37.8  270  57 29   6.3   3.5 | -37.3 -35.1  290  63 32   6.1   3.3
 22000 -36.8 -34.2  270  55 29   6.8   3.7 | -35.5 -31.9  285  60 31   6.1   3.4
 21000 -34.7 -30.5  265  54 28   6.8   3.7 | -33.7 -28.7  285  57 30   6.1   3.4
 20000 -32.7 -26.9  265  53 27   6.6   3.6 | -32.1 -25.8  280  54 28   3.0   1.7
 19500 -31.7 -25.1  265  52 27   6.6   3.6 | -31.6 -24.9  285  52 27   3.3   1.8
 19000 -30.7 -23.3  265  51 26   6.6   3.6 | -31.1 -24.0  285  49 25   3.3   1.8
 18500 -29.7 -21.5  265  50 26   6.6   3.6 | -30.6 -23.1  285  47 24   3.3   1.8
 18000 -28.7 -19.7  265  49 25   6.6   3.6 | -30.1 -22.2  285  45 23   3.6   2.0
 17500 -27.8 -18.0  265  47 24   5.5   3.0 | -29.3 -20.7  285  43 22   6.5   3.6
 17000 -27.0 -16.6  265  45 23   5.5   3.0 | -28.4 -19.1  285  41 21   6.5   3.6
 16500 -26.2 -15.2  270  43 22   6.2   3.4 | -27.5 -17.5  285  38 20   4.9   2.7
 16000 -25.2 -13.4  270  40 21   6.3   3.4 | -26.8 -16.2  285  35 18   4.9   2.7
 15500 -24.3 -11.7  270  37 19   6.2   3.4 | -26.1 -15.0  285  32 16   6.0   3.3
 15000 -23.4 -10.1  270  33 17   6.1   3.3 | -25.1 -13.2  285  29 15   6.6   3.6
 14500 -22.0  -7.6  270  30 15   6.5   3.5 | -23.5 -10.3  285  25 13   8.8   4.8
 14000 -21.1  -6.0  270  30 15   6.4   3.5 | -22.2  -8.0  285  23 12   8.6   4.7
 13500 -20.0  -4.0  265  29 15   7.5   4.1 | -21.0  -5.8  285  22 11   8.2   4.5
 13000 -18.9  -2.0  270  28 15   7.6   4.2 | -19.7  -3.5  290  20 10   8.2   4.5
 12500 -17.8  -0.0  270  28 14   8.0   4.4 | -18.5  -1.3  290  19 10   8.5   4.7
 12000 -16.6   2.1  270  27 14   8.1   4.4 | -17.2   1.0  290  18  9   8.5   4.7
 11500 -15.4   4.3  270  26 13   8.1   4.4 | -16.0   3.2  295  17  9   8.2   4.5
 11000 -14.2   6.4  270  24 12   8.2   4.5 | -14.8   5.4  295  16  8   8.3   4.5
 10500 -13.0   8.6  275  22 12   7.3   4.0 | -13.6   7.5  295  15  8   7.9   4.3
 10250 -12.5   9.5  275  22 11   6.8   3.7 | -13.0   8.6  295  14  7   7.1   3.9
 10000 -12.0  10.4  275  21 11   8.8   4.8 | -12.4   9.7  295  14  7  10.1   5.6
  9750 -11.3  11.7  280  20 10   9.1   5.0 | -11.6  11.1  290  14  7  10.5   5.8
  9500 -10.7  12.7  280  19 10   7.2   4.0 | -10.9  12.4  290  14  7   7.7   4.3
  9250 -10.1  13.8  280  18  9   7.8   4.3 | -10.3  13.5  285  14  7   8.5   4.7
  9000  -9.6  14.7  285  17  9   7.4   4.1 |  -9.7  14.5  285  14  7   8.2   4.5
  8750  -9.0  15.8  285  16  8   7.3   4.0 |  -9.1  15.6  285  13  7   8.9   4.9
  8500  -8.5  16.7  285  15  8   7.6   4.1 |  -8.4  16.9  285  13  7   9.5   5.2
  8250  -8.0  17.6  290  14  7   7.1   3.9 |  -7.7  18.1  285  13  7   9.4   5.2
  8000  -7.4  18.7  290  13  7   9.8   5.4 |  -7.0  19.4  285  13  7   9.9   5.4
  7750  -6.6  20.1  290  13  7  10.9   6.0 |  -6.3  20.7  285  12  6   9.6   5.3
  7500  -5.9  21.4  290  13  7   9.1   5.0 |  -5.6  21.9  285  12  6   8.9   4.9
  7250  -5.2  22.6  290  13  6  10.0   5.5 |  -4.9  23.2  285  12  6   9.9   5.4
  7000  -4.4  24.1  290  12  6  10.5   5.7 |  -4.1  24.6  285  12  6  10.8   5.9
  6750  -3.6  25.5  290  12  6   9.9   5.4 |  -3.3  26.1  285  12  6   9.5   5.2
  6500  -2.9  26.8  290  12  6   9.6   5.2 |  -2.7  27.1  285  12  6   9.3   5.1
  6250  -2.2  28.0  290  12  6  10.7   5.9 |  -1.9  28.6  285  11  6  10.6   5.8
  6000  -1.3  29.7  285  12  6  11.4   6.3 |  -1.1  30.0  285  11  6  10.8   5.9
  5750  -0.5  31.1  285  11  6  11.2   6.1 |  -0.3  31.5  285  10  5   9.5   5.2
  5500   0.4  32.7  285  11  5  12.2   6.7 |   0.3  32.5  285  10  5   8.1   4.4
  5250   1.3  34.3  290  11  6  14.1   7.7 |   0.9  33.6  285  10  5   7.7   4.2
  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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