Soaring Guidance
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14
000
UXUS97 KBOU 140058
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1857 MDT Friday, October 13, 2017

This forecast is for Saturday, October 14, 2017:

If the trigger temperature of 66.0 F/18.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 34 ft/min (0.2 m/s)
   Maximum height of thermals.................. 6000 ft MSL (693 ft AGL)

Forecast maximum temperature................... 57.0 F/14.3 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5622 ft MSL (316 ft AGL)
Thermal soaring outlook for Sunday 10/15....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Improving
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 40491 ft MSL (35184 ft AGL)
Wave soaring outlook for Sunday 10/15.......... Good

Remarks...

Sunrise/Sunset.................... 07:09:05 / 18:22:40 MDT
Total possible sunshine........... 11 hr 13 min 35 sec (673 min 35 sec)
Altitude of sun at 12:45:25 MDT... 41.82 degrees

Upper air data from numerical model forecast valid on 10/14/2017 at 0600 MDT

Freezing level.................. 12790 ft MSL (7483 ft AGL)
Convective condensation level... 19922 ft MSL (14615 ft AGL)
Lifted condensation level....... 13796 ft MSL (8489 ft AGL)
Lifted index.................... +11.8
K index......................... -20.8

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  -65.2 -85.4   250   77   40   0.7   0.4      M     M       M      M    M
 45000  -62.6 -80.7   245  112   57   6.4   3.5      M     M       M      M    M
 40000  -53.2 -63.8   240  116   60   6.2   3.4      M     M       M      M    M
 38000  -50.1 -58.2   240  112   58   5.0   2.8      M     M       M      M    M
 36000  -47.0 -52.6   240  108   55   5.1   2.8      M     M       M      M    M
 34000  -43.4 -46.1   240  105   54   7.1   3.9      M     M       M      M    M
 32000  -38.6 -37.5   240  103   53   7.1   3.9      M     M       M      M    M
 30000  -34.5 -30.1   240  100   51   6.7   3.6   41.9 107.4    21.2      M    M
 29000  -32.5 -26.5   245   97   50   6.6   3.6   40.6 105.1    20.5      M    M
 28000  -30.5 -22.9   245   94   48   6.7   3.7   39.5 103.2    19.9      M    M
 27000  -28.5 -19.3   245   90   46   7.0   3.8   38.4 101.2    19.2      M    M
 26000  -26.4 -15.5   250   86   44   7.0   3.8   37.3  99.2    18.6      M    M
 25000  -24.3 -11.7   250   82   42   7.0   3.9   36.3  97.4    18.0      M    M
 24000  -22.3  -8.1   250   77   40   5.6   3.1   35.3  95.5    17.4      M    M
 23000  -20.5  -4.9   255   71   37   5.8   3.2   33.7  92.7    16.3      M    M
 22000  -18.8  -1.8   255   65   33   5.8   3.2   32.3  90.2    15.3      M    M
 21000  -16.8   1.8   255   60   31   7.8   4.3   31.2  88.1    14.5      M    M
 20000  -14.5   5.9   255   58   30   7.7   4.2   30.4  86.7    14.0      M    M
 19500  -13.4   7.9   255   57   30   7.7   4.2   30.0  86.1    13.8      M    M
 19000  -12.3   9.9   255   57   29   7.7   4.2   29.7  85.5    13.6      M    M
 18500  -11.1  12.0   255   56   29   7.7   4.2   29.4  84.9    13.4      M    M
 18000  -10.0  14.0   255   55   28   7.6   4.2   29.0  84.2    13.2      M    M
 17500   -8.8  16.2   255   54   28   7.2   4.0   28.7  83.6    12.9      M    M
 17000   -7.8  18.0   255   53   27   6.6   3.6   28.1  82.6    12.5      M    M
 16500   -6.3  20.7   250   50   26   6.0   3.3   27.3  81.2    11.9      M    M
 16000   -5.5  22.1   250   48   25   5.5   3.0   26.6  79.9    11.3      M    M
 15500   -4.7  23.5   245   45   23   5.4   3.0   25.9  78.6    10.7      M    M
 15000   -3.9  25.0   240   41   21   4.8   2.6   25.1  77.2    10.1      M    M
 14500   -3.2  26.2   235   38   19   4.6   2.5   24.3  75.7     9.4      M    M
 14000   -2.4  27.7   230   35   18   6.8   3.7   23.6  74.5     8.8      M    M
 13500   -1.4  29.5   225   33   17   6.7   3.7   23.1  73.6     8.4      M    M
 13000   -0.4  31.3   225   31   16   8.0   4.4   22.7  72.9     8.0      M    M
 12500    0.9  33.6   235   32   17   8.2   4.5   22.4  72.4     7.8      M    M
 12000    2.0  35.6   245   35   18   6.1   3.3   22.1  71.8     7.5      M    M
 11500    2.8  37.0   255   40   21   5.4   3.0   21.4  70.5     6.9      M    M
 11000    3.5  38.3   260   45   23   5.0   2.8   20.7  69.2     6.2      M    M
 10500    4.2  39.6   260   41   21   4.2   2.3   19.9  67.9     5.5      M    M
 10250    4.6  40.3   260   39   20   8.6   4.7   19.6  67.2     5.1      M    M
 10000    5.4  41.7   265   37   19  10.4   5.7   19.7  67.4     5.2      M    M
  9750    6.0  42.8   265   35   18   7.3   4.0   19.5  67.1     5.0      M    M
  9500    6.5  43.7   265   32   17   8.1   4.4   19.4  66.9     4.9      M    M
  9250    7.1  44.8   270   30   15   8.1   4.4   19.2  66.6     4.8      M    M
  9000    7.7  45.9   270   28   14   8.3   4.6   19.1  66.4     4.7      M    M
  8750    8.3  46.9   270   26   13   8.2   4.5   19.0  66.2     4.5      M    M
  8500    8.9  48.0   275   24   12   8.2   4.5   18.9  66.0     4.4      M    M
  8250    9.5  49.1   275   22   11   8.3   4.5   18.8  65.8     4.3      M    M
  8000   10.2  50.4   275   20   10   8.2   4.5   18.7  65.6     4.2      M    M
  7750   10.7  51.3   280   18    9   7.7   4.2   18.5  65.3     4.1      M    M
  7500   11.3  52.3   280   17    9   7.6   4.2   18.4  65.0     3.9      M    M
  7250   11.8  53.2   280   15    8   6.8   3.7   18.2  64.7     3.7      M    M
  7000   12.3  54.1   285   14    7   5.7   3.1   17.9  64.2     3.5      M    M
  6750   12.7  54.9   285   13    7   6.9   3.8   17.6  63.7     3.2      M    M
  6500   13.1  55.6   285   12    6   1.7   0.9   17.3  63.1     2.9      M    M
  6250   12.8  55.0   280   11    6  -8.5  -4.6   16.3  61.3     1.8      M    M
  6000   12.0  53.6   270   10    5  -9.7  -5.3   14.8  58.6     0.3      M    M
  5750   11.2  52.2   260    9    5 -13.4  -7.4   13.3  55.9    -1.3     47  0.2
  5500    9.5  49.1   245    8    4 -34.1 -18.7   10.9  51.6    -3.7     91  0.5

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

           10/14/2017 at 0900 MDT          |       10/14/2017 at 1200 MDT
                                           |
K index... -25.4  LI... +9.6               | K index... -8.0  LI... +11.3
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 -65.0 -85.0  250  83 43   1.7   0.9 | -63.0 -81.4  250  88 45   0.8   0.4
 45000 -61.4 -78.5  245 111 57   5.7   3.1 | -60.8 -77.4  245 107 55   5.3   2.9
 40000 -52.8 -63.0  240 114 59   5.9   3.2 | -52.8 -63.0  245 107 55   5.3   2.9
 38000 -50.0 -58.0  240 112 57   4.5   2.5 | -49.9 -57.8  245 104 54   4.8   2.6
 36000 -47.3 -53.1  240 109 56   4.5   2.5 | -47.0 -52.6  245 101 52   4.8   2.6
 34000 -44.1 -47.4  240 105 54   6.2   3.4 | -43.8 -46.8  240  97 50   6.0   3.3
 32000 -40.4 -40.7  240 102 52   6.2   3.4 | -40.3 -40.5  240  93 48   6.0   3.3
 30000 -36.1 -33.0  245  96 49   6.7   3.7 | -36.0 -32.8  240  88 46   6.7   3.7
 29000 -34.0 -29.2  245  93 48   6.7   3.7 | -34.0 -29.2  240  86 44   6.7   3.7
 28000 -32.0 -25.6  245  89 46   6.7   3.7 | -32.0 -25.6  245  84 43   6.7   3.7
 27000 -30.0 -22.0  250  86 44   6.6   3.6 | -30.0 -22.0  245  83 43   6.6   3.6
 26000 -28.1 -18.6  250  82 42   6.6   3.6 | -28.0 -18.4  245  82 42   6.6   3.6
 25000 -26.1 -15.0  250  78 40   6.6   3.6 | -26.0 -14.8  250  82 42   6.6   3.6
 24000 -24.0 -11.2  250  75 39   8.0   4.4 | -24.0 -11.2  250  82 42   6.8   3.7
 23000 -21.7  -7.1  250  72 37   7.9   4.3 | -22.0  -7.6  250  80 41   6.8   3.8
 22000 -19.3  -2.7  250  69 36   7.9   4.3 | -19.9  -3.8  250  79 41   6.8   3.8
 21000 -17.0   1.4  250  67 34   7.3   4.0 | -17.8  -0.0  250  76 39   8.0   4.4
 20000 -14.8   5.4  250  65 33   7.4   4.0 | -15.5   4.1  245  69 35   7.9   4.3
 19500 -13.7   7.3  250  64 33   7.4   4.1 | -14.3   6.3  245  65 34   7.9   4.3
 19000 -12.6   9.3  250  63 32   7.4   4.1 | -13.1   8.4  240  62 32   8.0   4.4
 18500 -11.5  11.3  250  61 32   6.7   3.7 | -12.0  10.4  240  60 31   5.5   3.0
 18000 -10.5  13.1  250  59 31   6.6   3.6 | -11.3  11.7  245  65 33   4.6   2.5
 17500  -9.6  14.7  245  58 30   6.4   3.5 | -10.6  12.9  250  70 36   4.2   2.3
 17000  -8.7  16.3  245  56 29   5.8   3.2 | -10.4  13.3  250  71 37   0.2   0.1
 16500  -7.8  18.0  245  54 28   5.8   3.2 | -10.3  13.5  250  70 36   0.6   0.3
 16000  -6.5  20.3  245  51 26   5.8   3.2 | -10.4  13.3  255  67 34  -1.2  -0.6
 15500  -5.6  21.9  240  50 25   5.8   3.2 | -10.6  12.9  255  62 32  -1.3  -0.7
 15000  -4.8  23.4  240  48 25   5.4   3.0 | -10.6  12.9  255  57 29   1.6   0.9
 14500  -4.0  24.8  240  47 24   5.4   3.0 | -10.4  13.3  260  51 26   1.1   0.6
 14000  -3.2  26.2  240  47 24   5.5   3.0 | -10.1  13.8  260  45 23   4.9   2.7
 13500  -2.4  27.7  245  47 24   5.6   3.1 |  -9.3  15.3  265  40 21   5.2   2.8
 13000  -1.6  29.1  245  46 24   3.9   2.1 |  -8.5  16.7  270  36 19   6.6   3.6
 12500  -1.1  30.0  250  44 23   3.6   2.0 |  -7.5  18.5  275  33 17   7.0   3.8
 12000  -0.6  30.9  255  42 21   4.0   2.2 |  -6.4  20.5  280  30 16   7.3   4.0
 11500   0.0  32.0  260  37 19   4.1   2.3 |  -5.3  22.5  290  28 14   7.3   4.0
 11000   0.7  33.3  265  32 17   5.5   3.0 |  -4.1  24.6  295  26 13   9.3   5.1
 10500   1.5  34.7  270  31 16   6.4   3.5 |  -2.7  27.1  300  26 13  10.8   5.9
 10250   2.0  35.6  270  31 16   5.0   2.8 |  -2.0  28.4  300  26 13   5.8   3.2
 10000   2.3  36.1  275  30 15   6.2   3.4 |  -1.7  28.9  300  25 13   7.0   3.8
  9750   2.9  37.2  275  28 15   8.4   4.6 |  -0.8  30.6  305  25 13  12.6   6.9
  9500   3.5  38.3  280  27 14   8.2   4.5 |   0.0  32.0  305  25 13  11.7   6.4
  9250   4.1  39.4  280  26 14   7.1   3.9 |   0.9  33.6  305  25 13   9.7   5.3
  9000   4.5  40.1  285  25 13   7.0   3.8 |   1.5  34.7  305  25 13   8.3   4.6
  8750   5.1  41.2  285  25 13   8.7   4.8 |   2.2  36.0  305  25 13  10.4   5.7
  8500   5.8  42.4  290  24 12   9.0   4.9 |   3.0  37.4  305  25 13  10.6   5.8
  8250   6.4  43.5  290  24 12   8.3   4.5 |   3.8  38.8  310  25 13  10.1   5.5
  8000   7.0  44.6  295  23 12   7.5   4.1 |   4.5  40.1  310  25 13   9.8   5.4
  7750   7.6  45.7  295  22 11   7.7   4.2 |   5.3  41.5  310  25 13  10.2   5.6
  7500   8.1  46.6  300  21 11   7.5   4.1 |   6.1  43.0  310  25 13  10.3   5.6
  7250   8.7  47.7  300  20 10   7.1   3.9 |   6.8  44.2  310  25 13  10.1   5.5
  7000   9.2  48.6  305  19 10   6.6   3.6 |   7.6  45.7  310  24 13  10.1   5.5
  6750   9.6  49.3  310  18 10   6.2   3.4 |   8.3  46.9  310  24 12   9.9   5.5
  6500   9.9  49.8  315  18  9  -0.1  -0.0 |   9.1  48.4  310  24 12  10.2   5.6
  6250   9.6  49.3  315  16  8  -5.7  -3.1 |   9.9  49.8  310  23 12  10.9   6.0
  6000   9.1  48.4  320  13  7  -5.0  -2.7 |  10.7  51.3  310  23 12   9.9   5.4
  5750   8.6  47.5  330  11  5  -6.8  -3.7 |  11.4  52.5  315  22 11  12.7   7.0
  5500   8.0  46.4  335   7  4  -6.0  -3.3 |  12.7  54.9  315  20 10  21.3  11.7

           10/14/2017 at 1500 MDT          |       10/14/2017 at 1800 MDT
                                           |
K index... +2.3  LI... +11.2               | K index... -8.8  LI... +9.8
CAPE... +1.0  CIN... -3.0                  | 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 -60.4 -76.7  255  74 38   0.8   0.4 | -58.8 -73.8  265  71 36   0.9   0.5
 45000 -58.7 -73.7  250 102 52   3.1   1.7 | -57.0 -70.6  260  89 46   3.0   1.6
 40000 -54.0 -65.2  250  91 47   3.1   1.7 | -52.4 -62.3  255  89 46   3.1   1.7
 38000 -51.3 -60.3  250  89 46   5.0   2.7 | -50.4 -58.7  255  85 44   3.5   1.9
 36000 -48.3 -54.9  255  90 46   5.0   2.7 | -48.3 -54.9  260  79 41   3.5   1.9
 34000 -45.1 -49.2  255  91 47   5.9   3.2 | -45.3 -49.5  265  76 39   5.6   3.1
 32000 -41.6 -42.9  255  93 48   5.9   3.2 | -42.0 -43.6  265  77 40   5.6   3.1
 30000 -37.6 -35.7  255  93 48   6.1   3.3 | -38.7 -37.7  265  76 39   5.3   2.9
 29000 -35.7 -32.3  255  91 47   6.1   3.3 | -37.1 -34.8  270  73 38   5.3   2.9
 28000 -33.9 -29.0  255  89 46   6.1   3.3 | -35.5 -31.9  270  71 37   5.3   2.9
 27000 -32.0 -25.6  260  87 45   7.2   4.0 | -33.8 -28.8  270  69 36   6.3   3.4
 26000 -29.9 -21.8  260  84 43   7.1   3.9 | -32.0 -25.6  275  67 35   6.3   3.4
 25000 -27.7 -17.9  260  82 42   7.1   3.9 | -30.1 -22.2  275  65 34   6.3   3.4
 24000 -25.6 -14.1  260  80 41   7.6   4.2 | -28.1 -18.6  275  63 32   8.0   4.4
 23000 -23.2  -9.8  260  80 41   7.8   4.3 | -25.5 -13.9  270  60 31   8.9   4.9
 22000 -20.9  -5.6  260  80 41   7.8   4.3 | -22.8  -9.0  265  57 29   9.0   4.9
 21000 -18.6  -1.5  260  79 41   7.1   3.9 | -20.3  -4.5  265  54 28   5.4   3.0
 20000 -16.4   2.5  255  74 38   7.2   3.9 | -18.6  -1.5  265  51 26   5.5   3.0
 19500 -15.4   4.3  255  72 37   7.2   3.9 | -17.8  -0.0  265  49 25   5.5   3.0
 19000 -14.3   6.3  255  69 36   7.3   4.0 | -17.0   1.4  270  47 24   5.6   3.1
 18500 -13.4   7.9  255  66 34   2.0   1.1 | -16.3   2.7  270  45 23   2.5   1.4
 18000 -13.5   7.7  250  61 31  -0.3  -0.1 | -16.1   3.0  280  43 22   1.4   0.8
 17500 -13.5   7.7  250  56 29  -0.6  -0.3 | -15.8   3.6  290  40 21  -0.6  -0.3
 17000 -13.8   7.2  255  53 27  -3.1  -1.7 | -16.0   3.2  295  37 19  -1.0  -0.5
 16500 -14.3   6.3  255  51 26  -2.9  -1.6 | -16.2   2.8  300  34 17   0.7   0.4
 16000 -14.9   5.2  265  47 24  -2.3  -1.3 | -15.7   3.7  305  33 17   3.8   2.1
 15500 -15.3   4.5  270  42 22  -2.4  -1.3 | -15.2   4.6  310  33 17   3.9   2.1
 15000 -15.0   5.0  275  40 20   6.3   3.4 | -14.5   5.9  315  32 17   4.5   2.4
 14500 -14.2   6.4  280  38 20   5.4   3.0 | -13.9   7.0  315  32 16   4.3   2.4
 14000 -13.3   8.1  280  36 18   7.0   3.9 | -13.1   8.4  315  31 16   6.4   3.5
 13500 -12.3   9.9  285  30 16   6.9   3.8 | -12.2  10.0  315  30 16   6.2   3.4
 13000 -11.2  11.8  290  27 14   8.6   4.7 | -11.2  11.8  320  29 15   7.1   3.9
 12500  -9.9  14.2  290  27 14   8.7   4.8 | -10.2  13.6  320  27 14   6.9   3.8
 12000  -8.6  16.5  295  27 14   8.9   4.9 |  -9.1  15.6  320  25 13   8.4   4.6
 11500  -7.3  18.9  300  27 14   8.9   4.9 |  -7.9  17.8  320  24 12   8.3   4.6
 11000  -5.9  21.4  305  27 14   9.2   5.1 |  -6.6  20.1  320  23 12   8.3   4.5
 10500  -4.6  23.7  310  27 14  10.3   5.6 |  -5.4  22.3  320  24 12   8.4   4.6
 10250  -3.9  25.0  310  27 14   5.1   2.8 |  -4.8  23.4  320  24 12   6.1   3.4
 10000  -3.6  25.5  310  27 14   6.7   3.7 |  -4.4  24.1  320  24 12   6.6   3.6
  9750  -2.7  27.1  310  27 14  13.4   7.4 |  -3.8  25.2  320  23 12   9.8   5.4
  9500  -1.8  28.8  310  27 14  11.9   6.5 |  -3.1  26.4  320  22 11   9.6   5.2
  9250  -1.0  30.2  310  27 14   9.6   5.3 |  -2.4  27.7  320  21 11   8.7   4.8
  9000  -0.4  31.3  310  27 14   8.6   4.7 |  -1.8  28.8  320  21 11   8.7   4.8
  8750   0.4  32.7  310  27 14  11.2   6.2 |  -1.1  30.0  320  21 11  11.1   6.1
  8500   1.3  34.3  315  27 14  11.0   6.0 |  -0.2  31.6  320  21 11  10.6   5.8
  8250   2.0  35.6  315  27 14   9.5   5.2 |   0.5  32.9  325  20 10   8.7   4.8
  8000   2.7  36.9  315  27 14   9.3   5.1 |   1.1  34.0  325  20 10   9.0   4.9
  7750   3.4  38.1  315  27 14  10.3   5.7 |   1.8  35.2  325  20 10   9.7   5.3
  7500   4.2  39.6  315  27 14  10.4   5.7 |   2.6  36.7  325  20 10  10.3   5.6
  7250   5.0  41.0  315  27 14   9.9   5.4 |   3.3  37.9  325  19 10  10.0   5.5
  7000   5.7  42.3  315  27 14  10.0   5.5 |   4.1  39.4  325  19 10  10.3   5.6
  6750   6.5  43.7  315  27 14   9.6   5.2 |   4.9  40.8  325  19 10  10.0   5.5
  6500   7.2  45.0  315  26 14  10.1   5.5 |   5.6  42.1  325  19 10   9.6   5.2
  6250   8.0  46.4  315  26 13  10.7   5.9 |   6.3  43.3  325  18  9   9.5   5.2
  6000   8.8  47.8  315  26 13  10.6   5.8 |   7.0  44.6  325  18  9   9.8   5.4
  5750   9.7  49.5  315  24 13  14.8   8.1 |   7.7  45.9  325  16  8   9.0   4.9
  5500  11.0  51.8  315  22 11  21.2  11.7 |   8.3  46.9  325  13  7   6.9   3.8
________________________________________________________________________________

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 near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.