Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 121406
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0706 MST Sunday, November 12, 2017

This forecast is for Sunday, November 12, 2017:

If the trigger temperature of 59.9 F/15.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 392 ft/min (2.0 m/s)
   Maximum height of thermals.................. 10184 ft MSL (5345 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... 1400 MST
Time of overdevelopment........................ 1700 MST
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7456 ft MSL (2616 ft AGL)
Thermal soaring outlook for Monday 11/13....... Good

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

Remarks...

Sunrise/Sunset.................... 06:54:23 / 17:02:59 MST
Total possible sunshine........... 10 hr 8 min 35 sec (608 min 35 sec)
Altitude of sun at 11:58:28 MST... 33.03 degrees

Upper air data from rawinsonde observation taken on 11/12/2017 at 0500 MST

Freezing level.................. 10452 ft MSL (5613 ft AGL)
Convective condensation level... 20136 ft MSL (15297 ft AGL)
Lifted condensation level....... 15476 ft MSL (10636 ft AGL)
Lifted index.................... +8.6
K index......................... -35.1

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  -61.5 -78.7   290   70   36   2.6   1.4   97.7 207.9    46.3      M    M
 45000  -59.3 -74.7   275   88   45   3.3   1.8   76.6 169.9    36.6      M    M
 40000  -58.7 -73.7   285   93   48   2.0   1.1   54.4 130.0    24.7      M    M
 38000  -56.1 -69.0   285   92   48   5.9   3.2   48.3 118.9    21.3      M    M
 36000  -53.1 -63.6   280   85   44   4.2   2.3   44.2 111.5    19.1      M    M
 34000  -49.9 -57.8   275   77   39   7.8   4.3   40.4 104.7    16.9      M    M
 32000  -44.8 -48.6   280   68   35   8.4   4.6   39.2 102.5    16.4      M    M
 30000  -39.6 -39.3   285   59   30   8.9   4.9   38.4 101.2    16.3      M    M
 29000  -37.0 -34.6   285   56   29   9.1   5.0   38.0 100.5    16.2      M    M
 28000  -34.6 -30.3   280   53   27   7.3   4.0   37.2  98.9    15.8      M    M
 27000  -32.5 -26.5   280   51   26   6.9   3.8   36.3  97.3    15.2      M    M
 26000  -30.6 -23.1   280   48   25   5.9   3.2   34.9  94.8    14.3      M    M
 25000  -28.5 -19.3   275   45   23   7.5   4.1   33.9  93.0    13.7      M    M
 24000  -26.4 -15.5   275   44   23   7.5   4.1   32.8  91.1    13.0      M    M
 23000  -24.3 -11.7   270   41   21   5.8   3.2   31.8  89.3    12.3      M    M
 22000  -22.5  -8.5   265   38   20   6.8   3.8   30.4  86.8    11.3      M    M
 21000  -19.9  -3.8   270   37   19   9.2   5.0   30.1  86.1    11.1      M    M
 20000  -16.5   2.3   275   37   19   9.2   5.0   29.9  85.8    11.1      M    M
 19500  -15.1   4.8   280   35   18   9.2   5.0   29.8  85.6    11.0      M    M
 19000  -13.7   7.3   280   34   18   9.3   5.1   29.7  85.4    11.0      M    M
 18500  -12.3   9.9   280   33   17   8.5   4.7   29.5  85.1    11.1      M    M
 18000  -10.9  12.4   280   33   17   6.6   3.6   29.4  84.9    11.0      M    M
 17500  -10.3  13.5   280   32   17   4.3   2.4   28.4  83.2    10.3      M    M
 17000   -9.6  14.7   280   32   16   4.2   2.3   27.5  81.5     9.5      M    M
 16500   -9.0  15.8   275   31   16   4.2   2.3   26.5  79.7     8.7      M    M
 16000   -8.4  16.9   270   30   15   4.2   2.3   25.6  78.1     7.9      M    M
 15500   -7.8  18.0   270   31   16   4.2   2.3   24.6  76.3     7.1      M    M
 15000   -7.1  19.2   270   31   16   4.0   2.2   23.7  74.6     6.3      M    M
 14500   -6.5  20.3   270   28   14   2.2   1.2   22.7  72.9     5.5      M    M
 14000   -6.5  20.3   275   25   13   0.5   0.3   21.2  70.1     4.1      M    M
 13500   -6.5  20.3   270   24   12   4.2   2.3   19.6  67.3     2.6      M    M
 13000   -5.4  22.3   265   23   12   7.4   4.0   19.3  66.7     2.3      M    M
 12500   -4.6  23.7   260   22   12   5.4   3.0   18.6  65.5     1.6      M    M
 12000   -3.6  25.5   255   22   11   6.8   3.7   18.1  64.7     1.1      M    M
 11500   -2.5  27.5   250   19   10   8.0   4.4   17.8  64.0     0.8      M    M
 11000   -1.3  29.7   240   16    8   7.9   4.4   17.5  63.4     0.5      M    M
 10500   -0.1  31.8   225   14    7   8.0   4.4   17.2  62.9     0.2      M    M
 10250    0.4  32.7   220   13    7   7.5   4.1   17.0  62.7     0.1      M    M
 10000    1.0  33.8   225   11    6   7.0   3.9   16.8  62.3    -0.1    376  1.9
  9750    1.5  34.7   220   10    5   7.1   3.9   16.6  61.9    -0.3    353  1.8
  9500    2.0  35.6   210    8    4   7.1   3.9   16.4  61.6    -0.5    330  1.7
  9250    2.6  36.7   200    7    4   7.1   3.9   16.2  61.2    -0.7    307  1.6
  9000    3.1  37.6   185    6    3   7.1   3.9   16.0  60.8    -0.9    283  1.4
  8750    3.6  38.5   180    7    4   7.1   3.9   15.8  60.5    -1.2    260  1.3
  8500    4.1  39.4   170    9    5   7.1   3.9   15.6  60.1    -1.4    237  1.2
  8250    4.7  40.5   170   11    6   7.2   4.0   15.4  59.7    -1.6    214  1.1
  8000    5.2  41.4   165   13    7   6.7   3.7   15.2  59.4    -1.8    190  1.0
  7750    5.7  42.3   160   14    7   8.6   4.7   15.0  59.0    -2.0    167  0.8
  7500    6.1  43.0   160   14    7  -4.6  -2.5   14.6  58.3    -2.4    149  0.8
  7250    5.2  41.4   155   15    8  -9.9  -5.4   13.0  55.3    -4.0    168  0.9
  7000    5.0  41.0   150   16    8   2.3   1.2   12.0  53.7    -4.9    166  0.8
  6750    5.3  41.5   145   15    8   5.0   2.8   11.6  52.8    -5.4    150  0.8
  6500    5.7  42.3   140   14    7   5.9   3.2   11.3  52.3    -5.7    130  0.7
  6250    6.2  43.2   135   12    6   5.5   3.0   11.0  51.7    -6.0    109  0.6
  6000    6.6  43.9   125   11    6   6.4   3.5   10.7  51.2    -6.3     89  0.5
  5750    7.0  44.6   120   10    5   2.4   1.3   10.3  50.6    -6.7     70  0.4
  5500    7.0  44.6   115   10    5   0.2   0.1    9.6  49.2    -7.4     62  0.3
  5250    7.0  44.6   105    9    5  -3.7  -2.0    8.8  47.9    -8.2     55  0.3
  5000    5.8  42.4   095    9    5 -31.4 -17.2    7.0  44.5   -10.1     84  0.4

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

           11/12/2017 at 0800 MST          |       11/12/2017 at 1100 MST
                                           |
K index... -9.5  LI... +6.6                | K index... -2.8  LI... +6.9
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 -63.4 -82.1  280  66 34   2.4   1.3 | -63.2 -81.8  275  70 36   2.7   1.5
 45000 -60.0 -76.0  275  86 44   1.1   0.6 | -59.3 -74.7  275  89 46   0.9   0.5
 40000 -58.4 -73.1  290 101 52   1.2   0.7 | -57.9 -72.2  290 123 64   0.4   0.2
 38000 -55.3 -67.5  285  96 49   5.4   3.0 | -54.8 -66.6  285 117 60   6.0   3.3
 36000 -52.1 -61.8  285  87 45   5.4   3.0 | -51.2 -60.2  280 106 55   6.0   3.3
 34000 -48.2 -54.8  280  80 41   7.4   4.0 | -47.5 -53.5  280  94 48   6.5   3.6
 32000 -43.8 -46.8  280  72 37   7.4   4.0 | -43.1 -45.6  275  75 39   6.5   3.6
 30000 -39.3 -38.7  280  64 33   7.5   4.1 | -38.9 -38.0  275  64 33   7.5   4.1
 29000 -37.0 -34.6  280  61 31   7.5   4.1 | -36.7 -34.1  275  60 31   7.5   4.1
 28000 -34.8 -30.6  280  58 30   7.5   4.1 | -34.4 -29.9  275  56 29   7.5   4.1
 27000 -32.5 -26.5  280  56 29   7.5   4.1 | -32.2 -26.0  275  53 27   7.3   4.0
 26000 -30.3 -22.5  280  55 28   7.5   4.1 | -30.0 -22.0  275  51 26   7.3   4.0
 25000 -28.0 -18.4  280  54 28   7.5   4.1 | -27.8 -18.0  275  50 26   7.3   4.0
 24000 -25.8 -14.4  280  53 27   7.2   3.9 | -25.6 -14.1  280  48 25   7.9   4.3
 23000 -23.6 -10.5  280  51 26   7.2   4.0 | -23.3  -9.9  280  46 24   7.8   4.3
 22000 -21.5  -6.7  280  48 25   7.2   4.0 | -20.9  -5.6  280  45 23   7.8   4.3
 21000 -18.8  -1.8  280  45 23   7.4   4.1 | -18.6  -1.5  280  43 22   7.5   4.1
 20000 -16.5   2.3  280  42 22   7.4   4.1 | -16.4   2.5  280  40 21   7.5   4.1
 19500 -15.4   4.3  280  41 21   7.4   4.1 | -15.3   4.5  280  39 20   7.5   4.1
 19000 -14.3   6.3  285  39 20   7.6   4.2 | -14.2   6.4  280  38 20   7.5   4.1
 18500 -13.2   8.2  280  38 19   7.7   4.2 | -13.1   8.4  280  37 19   7.3   4.0
 18000 -12.0  10.4  280  36 19   7.7   4.2 | -11.5  11.3  280  34 18   7.3   4.0
 17500 -10.9  12.4  280  35 18   7.1   3.9 | -10.4  13.3  280  33 17   7.0   3.9
 17000  -9.8  14.4  280  33 17   7.2   3.9 |  -9.4  15.1  280  31 16   7.1   3.9
 16500  -8.8  16.2  280  32 17   6.8   3.7 |  -8.3  17.1  280  29 15   6.6   3.6
 16000  -7.7  18.1  280  31 16   6.6   3.6 |  -7.3  18.9  275  28 14   6.6   3.6
 15500  -6.7  19.9  280  29 15   5.8   3.2 |  -6.3  20.7  275  26 13   6.2   3.4
 15000  -6.0  21.2  280  28 14   4.5   2.5 |  -5.4  22.3  270  24 12   5.8   3.2
 14500  -5.3  22.5  275  26 13   4.4   2.4 |  -4.5  23.9  270  23 12   5.4   3.0
 14000  -4.7  23.5  270  24 12   3.7   2.0 |  -3.9  25.0  265  21 11   4.1   2.3
 13500  -4.2  24.4  265  22 11   3.8   2.1 |  -3.2  26.2  260  20 10   4.2   2.3
 13000  -3.6  25.5  260  21 11   4.6   2.5 |  -2.6  27.3  255  20 10   4.5   2.4
 12500  -3.0  26.6  255  20 10   4.3   2.4 |  -2.0  28.4  250  19 10   4.5   2.4
 12000  -2.2  28.0  250  19 10   7.2   4.0 |  -1.3  29.7  245  19 10   5.8   3.2
 11500  -1.2  29.8  250  18  9   7.0   3.8 |  -0.5  31.1  240  19 10   5.7   3.1
 11000  -0.1  31.8  245  17  9   7.4   4.1 |   0.4  32.7  235  18  9   7.2   4.0
 10500   1.0  33.8  240  15  8   7.7   4.2 |   1.5  34.7  230  16  8   7.2   3.9
 10250   1.5  34.7  240  14  7   5.0   2.8 |   1.9  35.4  230  15  8   5.1   2.8
 10000   1.8  35.2  235  13  7   5.0   2.7 |   2.3  36.1  225  15  7   6.2   3.4
  9750   2.3  36.1  230  12  6   7.8   4.3 |   2.9  37.2  225  14  7   8.7   4.8
  9500   2.9  37.2  225  11  6   7.2   4.0 |   3.5  38.3  220  13  7   7.7   4.2
  9250   3.4  38.1  215  11  6   5.5   3.0 |   4.1  39.4  215  13  6   6.1   3.3
  9000   3.7  38.7  210  11  6   4.5   2.4 |   4.5  40.1  215  12  6   5.5   3.0
  8750   4.1  39.4  205  11  6   5.5   3.0 |   4.9  40.8  215  12  6   6.7   3.7
  8500   4.5  40.1  195  11  6   4.4   2.4 |   5.4  41.7  210  13  7   5.5   3.0
  8250   4.7  40.5  190  12  6   2.1   1.2 |   5.7  42.3  205  13  7   3.6   2.0
  8000   4.9  40.8  185  13  6   1.7   0.9 |   6.0  42.8  205  13  7   3.4   1.8
  7750   5.0  41.0  180  13  7   2.2   1.2 |   6.3  43.3  195  13  7   3.7   2.0
  7500   5.1  41.2  175  14  7  -0.1  -0.0 |   6.5  43.7  190  13  7   1.7   0.9
  7250   5.0  41.0  170  13  7  -2.2  -1.2 |   6.5  43.7  185  11  6   0.3   0.2
  7000   4.9  40.8  165  12  6  -1.3  -0.7 |   6.6  43.9  175  10  5  -0.0  -0.0
  6750   4.8  40.6  160  12  6  -2.8  -1.5 |   6.6  43.9  165   9  5   2.4   1.3
  6500   4.4  39.9  150  11  5  -6.3  -3.4 |   7.0  44.6  160   8  4   7.8   4.3
  6250   3.9  39.0  140   9  5  -6.0  -3.3 |   7.6  45.7  160   7  3   9.1   5.0
  6000   3.4  38.1  130   8  4  -9.9  -5.4 |   8.3  46.9  160   6  3   8.6   4.7
  5750   2.3  36.1  120   8  4 -18.0  -9.9 |   9.0  48.2  155   5  3  13.2   7.2
  5500   0.9  33.6  105   6  3 -18.6 -10.2 |  10.3  50.5  155   5  2  21.1  11.5
  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

           11/12/2017 at 1400 MST          |       11/12/2017 at 1700 MST
                                           |
K index... -1.4  LI... +6.0                | K index... -3.3  LI... +4.4
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 -64.1 -83.4  275  80 41   2.1   1.1 | -64.7 -84.5  275  80 41   2.1   1.1
 45000 -60.9 -77.6  270 100 51   2.0   1.1 | -61.4 -78.5  275 101 52   2.2   1.2
 40000 -57.9 -72.2  285 116 60   1.6   0.9 | -58.2 -72.8  280 109 56   1.8   1.0
 38000 -54.8 -66.6  285 111 57   5.9   3.2 | -55.0 -67.0  275 105 54   5.8   3.2
 36000 -51.3 -60.3  280 105 54   5.9   3.2 | -51.5 -60.7  275 101 52   5.8   3.2
 34000 -47.4 -53.3  275  97 50   7.0   3.8 | -47.7 -53.9  270  93 48   7.2   4.0
 32000 -42.7 -44.9  275  84 43   7.0   3.8 | -42.8 -45.0  270  80 41   7.2   4.0
 30000 -38.3 -36.9  270  71 37   7.8   4.3 | -38.3 -36.9  270  67 35   7.7   4.2
 29000 -36.0 -32.8  270  64 33   7.8   4.3 | -36.0 -32.8  270  60 31   7.7   4.2
 28000 -33.6 -28.5  265  58 30   7.8   4.3 | -33.8 -28.8  265  53 28   7.7   4.2
 27000 -31.4 -24.5  265  53 27   7.3   4.0 | -31.3 -24.3  265  50 26   8.4   4.6
 26000 -29.2 -20.6  265  48 25   7.3   4.0 | -28.8 -19.8  265  49 25   8.5   4.7
 25000 -27.1 -16.8  265  44 23   7.3   4.0 | -26.3 -15.3  265  48 25   8.5   4.7
 24000 -25.0 -13.0  270  40 21   6.1   3.4 | -23.9 -11.0  260  47 24   7.1   3.9
 23000 -23.2  -9.8  270  37 19   6.2   3.4 | -21.8  -7.2  260  45 23   7.2   3.9
 22000 -21.3  -6.3  275  33 17   6.3   3.4 | -19.7  -3.5  255  44 22   7.1   3.9
 21000 -19.2  -2.6  275  32 16   7.8   4.3 | -18.1  -0.6  255  40 20   3.5   1.9
 20000 -16.9   1.6  275  32 16   7.9   4.3 | -17.1   1.2  250  33 17   3.4   1.9
 19500 -15.7   3.7  275  31 16   7.9   4.3 | -16.6   2.1  250  30 15   3.4   1.9
 19000 -14.5   5.9  275  31 16   7.9   4.3 | -16.1   3.0  245  27 14   3.8   2.1
 18500 -12.7   9.1  270  30 16   7.8   4.3 | -14.5   5.9  250  26 13   8.1   4.4
 18000 -11.6  11.1  270  29 15   7.8   4.3 | -13.3   8.1  250  26 13   8.3   4.6
 17500 -10.4  13.3  270  29 15   7.6   4.2 | -11.9  10.6  250  26 13   9.8   5.4
 17000  -9.3  15.3  265  28 14   7.6   4.2 | -10.4  13.3  255  26 13   9.7   5.3
 16500  -8.2  17.2  265  27 14   7.3   4.0 |  -9.0  15.8  255  26 13   8.9   4.9
 16000  -7.1  19.2  265  26 13   7.3   4.0 |  -7.6  18.3  255  26 13   8.8   4.8
 15500  -6.0  21.2  260  25 13   6.8   3.7 |  -6.3  20.7  255  26 13   8.0   4.4
 15000  -5.0  23.0  255  24 12   6.4   3.5 |  -5.2  22.6  255  25 13   7.2   3.9
 14500  -4.1  24.6  255  23 12   6.3   3.5 |  -4.1  24.6  255  25 13   6.7   3.7
 14000  -3.2  26.2  250  23 12   5.9   3.3 |  -3.3  26.1  255  25 13   4.9   2.7
 13500  -2.3  27.9  245  22 11   5.9   3.2 |  -2.5  27.5  250  25 13   5.0   2.7
 13000  -1.5  29.3  245  22 11   4.7   2.6 |  -1.8  28.8  250  24 12   5.2   2.9
 12500  -0.8  30.6  240  22 11   4.8   2.7 |  -1.0  30.2  245  24 12   5.2   2.9
 12000  -0.1  31.8  240  21 11   4.9   2.7 |  -0.2  31.6  240  22 12   6.9   3.8
 11500   0.6  33.1  235  20 10   4.8   2.6 |   0.7  33.3  230  21 11   6.8   3.7
 11000   1.4  34.5  230  19 10   7.0   3.9 |   1.8  35.2  225  19 10   8.5   4.6
 10500   2.4  36.3  225  18  9   6.9   3.8 |   3.1  37.6  220  18  9   8.6   4.7
 10250   2.9  37.2  225  18  9   5.4   3.0 |   3.6  38.5  220  17  9   3.8   2.1
 10000   3.3  37.9  220  17  9   6.2   3.4 |   3.8  38.8  215  16  8   5.6   3.1
  9750   3.8  38.8  220  16  8   7.9   4.4 |   4.5  40.1  215  16  8  11.0   6.0
  9500   4.4  39.9  215  15  8   7.4   4.0 |   5.3  41.5  210  15  8   9.3   5.1
  9250   4.9  40.8  215  14  7   6.9   3.8 |   5.9  42.6  210  14  7   6.3   3.5
  9000   5.4  41.7  215  13  7   6.3   3.5 |   6.3  43.3  205  13  7   5.5   3.0
  8750   5.9  42.6  210  12  6   6.3   3.5 |   6.8  44.2  200  12  6   7.9   4.3
  8500   6.4  43.5  205  10  5   5.6   3.1 |   7.4  45.3  195  11  6   7.2   4.0
  8250   6.7  44.1  200   9  5   4.2   2.3 |   7.9  46.2  195  10  5   6.1   3.3
  8000   7.0  44.6  195   7  4   4.1   2.3 |   8.3  46.9  190  10  5   5.8   3.2
  7750   7.3  45.1  190   6  3   4.3   2.4 |   8.7  47.7  185   9  5   6.3   3.5
  7500   7.7  45.9  180   4  2   6.0   3.3 |   9.2  48.6  180   8  4   5.7   3.1
  7250   8.2  46.8  180   3  2   7.4   4.0 |   9.6  49.3  175   7  3   5.0   2.7
  7000   8.8  47.8  180   3  1   6.8   3.7 |  10.0  50.0  175   6  3   5.1   2.8
  6750   9.3  48.7  185   2  1   8.8   4.8 |  10.3  50.5  175   4  2   4.9   2.7
  6500  10.1  50.2  190   2  1  10.3   5.6 |  10.7  51.3  180   3  1   5.9   3.2
  6250  10.8  51.4  195   2  1  10.0   5.5 |  11.2  52.2  200   2  1   6.4   3.5
  6000  11.5  52.7  205   2  1   9.7   5.3 |  11.7  53.1  240   1  1   6.9   3.8
  5750  12.3  54.1  210   2  1  12.9   7.1 |  12.2  54.0  260   2  1   4.7   2.6
  5500  13.5  56.3  215   2  1  19.2  10.5 |  12.3  54.1  275   2  1  -1.2  -0.7
  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 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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