Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 290131
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1831 MST Sunday, December 28, 2014

This forecast is for Monday, December 29, 2014:

If the trigger temperature of 33.1 F/0.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5404 ft MSL (117 ft AGL)

Forecast maximum temperature................... 14.0 F/-10.5 C
Time of trigger temperature.................... None
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................. None
Thermal soaring outlook for Tuesday 12/30...... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 44200 ft MSL (38913 ft AGL)
Wave soaring outlook for Tuesday 12/30......... Poor

Remarks...

Sunrise/Sunset.................... 07:19:58 / 16:43:23 MST
Total possible sunshine........... 9 hr 23 min 25 sec (563 min 25 sec)
Altitude of sun at 12:01:38 MST... 27.10 degrees

Upper air data from numerical model forecast valid on 12/29/2014 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 11972 ft MSL (6685 ft AGL)
Lifted condensation level....... 7109 ft MSL (1822 ft AGL)
Lifted index.................... +15.3
K index......................... +6.5

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  -53.1 -63.6   275   50   25   3.0   1.7      M     M       M      M    M
 45000  -48.3 -54.9   280   80   41   3.1   1.7      M     M       M      M    M
 40000  -49.0 -56.2   270   74   38  -1.1  -0.6      M     M       M      M    M
 38000  -49.7 -57.5   265   69   36  -0.2  -0.1      M     M       M      M    M
 36000  -48.7 -55.7   265   67   34   1.6   0.9      M     M       M      M    M
 34000  -47.7 -53.9   265   64   33   1.6   0.9      M     M       M      M    M
 32000  -47.0 -52.6   265   62   32   0.8   0.5      M     M       M      M    M
 30000  -46.5 -51.7   265   60   31   0.8   0.5      M     M       M      M    M
 29000  -46.2 -51.2   265   59   30   0.6   0.3   29.5  85.1    29.6      M    M
 28000  -46.0 -50.8   265   57   29   0.6   0.3   25.7  78.3    27.1      M    M
 27000  -45.9 -50.6   265   54   28   0.6   0.3   22.1  71.8    24.7      M    M
 26000  -45.7 -50.3   265   52   27   1.2   0.7   18.8  65.8    22.4      M    M
 25000  -44.6 -48.3   265   51   26   4.0   2.2   16.3  61.3    20.7      M    M
 24000  -43.4 -46.1   265   50   26   3.9   2.2   14.0  57.3    19.2      M    M
 23000  -42.3 -44.1   265   50   26   4.4   2.4   12.0  53.6    17.8      M    M
 22000  -40.6 -41.1   270   48   25   5.9   3.2   10.4  50.7    16.7      M    M
 21000  -38.8 -37.8   270   46   24   5.9   3.2    9.0  48.2    15.8      M    M
 20000  -37.0 -34.6   270   43   22   6.2   3.4    7.7  45.9    14.9      M    M
 19500  -36.1 -33.0   270   40   20   6.2   3.4    7.0  44.6    14.4      M    M
 19000  -35.2 -31.4   265   37   19   6.2   3.4    6.4  43.5    13.9      M    M
 18500  -34.2 -29.6   265   34   18   6.2   3.4    5.8  42.4    13.5      M    M
 18000  -33.3 -27.9   265   31   16   6.0   3.3    5.2  41.4    13.1      M    M
 17500  -32.1 -25.8   265   29   15  10.2   5.6    5.0  40.9    12.9      M    M
 17000  -30.6 -23.1   265   27   14   9.9   5.4    5.0  40.9    13.0      M    M
 16500  -29.2 -20.6   265   25   13   8.8   4.8    4.9  40.9    13.0      M    M
 16000  -27.3 -17.1   265   20   10   8.6   4.7    4.6  40.3    12.9      M    M
 15500  -26.1 -15.0   270   17    9   7.8   4.3    4.4  39.8    12.7      M    M
 15000  -24.9 -12.8   270   14    7   7.9   4.3    4.0  39.3    12.5      M    M
 14500  -23.7 -10.7   270   12    6   8.3   4.5    3.8  38.8    12.3      M    M
 14000  -22.5  -8.5   275   10    5   8.3   4.5    3.5  38.3    12.1      M    M
 13500  -21.2  -6.2   275    9    4   8.1   4.5    3.3  37.9    12.0      M    M
 13000  -20.0  -4.0   280    7    4   8.1   4.5    3.0  37.4    11.8      M    M
 12500  -18.8  -1.8   285    6    3   8.0   4.4    2.7  36.9    11.6      M    M
 12000  -17.6   0.3   295    5    3   8.0   4.4    2.4  36.4    11.4      M    M
 11500  -16.4   2.5   310    5    3   8.3   4.6    2.2  35.9    11.2      M    M
 11000  -15.1   4.8   320    5    3   8.6   4.7    1.9  35.5    11.1      M    M
 10500  -14.0   6.8   330    6    3   6.5   3.5    1.6  34.9    10.8      M    M
 10250  -13.6   7.5   335    6    3   5.7   3.1    1.3  34.4    10.5      M    M
 10000  -13.1   8.4   340    6    3   9.1   5.0    1.1  33.9    10.3      M    M
  9750  -12.3   9.9   350    6    3   9.8   5.4    1.1  34.1    10.4      M    M
  9500  -11.7  10.9   355    7    3   6.7   3.7    1.0  33.7    10.3      M    M
  9250  -11.2  11.8   360    7    4   7.7   4.2    0.8  33.4    10.1      M    M
  9000  -10.6  12.9   005    8    4   6.8   3.7    0.6  33.1    10.0      M    M
  8750  -10.2  13.6   010    8    4   6.7   3.7    0.3  32.6     9.7      M    M
  8500   -9.6  14.7   010    9    5   7.3   4.0    0.1  32.2     9.5      M    M
  8250   -9.1  15.6   010    9    5   7.2   3.9   -0.1  31.9     9.4      M    M
  8000   -8.6  16.5   010   10    5   6.5   3.5   -0.3  31.5     9.2      M    M
  7750   -8.2  17.2   015   10    5   5.0   2.8   -0.6  30.9     8.9      M    M
  7500   -7.8  18.0   020   10    5   4.7   2.6   -1.0  30.2     8.5      M    M
  7250   -7.5  18.5   020    9    5   4.0   2.2   -1.4  29.5     8.2      M    M
  7000   -7.2  19.0   025    9    5   3.0   1.6   -1.9  28.6     7.7      M    M
  6750   -7.0  19.4   030    9    4   2.8   1.5   -2.4  27.7     7.2      M    M
  6500   -6.9  19.6   030    8    4   0.4   0.2   -3.0  26.6     6.6      M    M
  6250   -7.1  19.2   030    8    4  -5.7  -3.2   -3.9  24.9     5.7      M    M
  6000   -7.7  18.1   020    6    3  -8.2  -4.5   -5.3  22.5     4.4      M    M
  5750   -8.3  17.1   010    5    3  -8.2  -4.5   -6.6  20.2     3.1      M    M
  5500   -9.1  15.6   325    4    2 -18.1  -9.9   -8.2  17.3     1.5      M    M

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

           12/29/2014 at 0800 MST          |       12/29/2014 at 1100 MST
                                           |
K index... +12.3  LI... +1.2               | K index... +9.6  LI... +2.5
CAPE... +7.7  CIN... -0.7                  | CAPE... 0.0  CIN... -3.1
                                           |
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 -53.5 -64.3  275  52 27   2.3   1.3 | -53.5 -64.3  275  46 24   2.2   1.2
 45000 -49.8 -57.6  275  70 36   2.4   1.3 | -50.0 -58.0  275  63 32   2.2   1.2
 40000 -48.7 -55.7  270  72 37   0.4   0.2 | -47.9 -54.2  275  67 35   1.3   0.7
 38000 -48.5 -55.3  265  73 37   0.9   0.5 | -47.1 -52.8  275  68 35   1.3   0.7
 36000 -47.4 -53.3  265  68 35   1.9   1.0 | -46.3 -51.3  270  65 33   1.4   0.8
 34000 -46.2 -51.2  265  63 32   1.9   1.0 | -45.4 -49.7  270  61 32   1.4   0.8
 32000 -45.8 -50.4  265  59 30  -0.5  -0.3 | -45.3 -49.5  270  57 29  -0.9  -0.5
 30000 -46.2 -51.2  265  55 28  -0.5  -0.3 | -45.9 -50.6  270  52 27  -0.9  -0.5
 29000 -46.3 -51.3  265  53 27  -0.5  -0.3 | -46.2 -51.2  270  49 25  -1.3  -0.7
 28000 -46.5 -51.7  265  50 26  -0.5  -0.3 | -46.6 -51.9  265  46 24  -1.3  -0.7
 27000 -46.7 -52.1  265  47 24  -0.5  -0.3 | -47.0 -52.6  265  42 22  -1.3  -0.7
 26000 -46.8 -52.2  265  44 23  -0.4  -0.2 | -47.4 -53.3  260  39 20  -1.3  -0.7
 25000 -46.2 -51.2  265  42 22   2.8   1.5 | -47.0 -52.6  260  35 18   1.7   0.9
 24000 -45.4 -49.7  265  41 21   2.7   1.5 | -46.5 -51.7  250  32 17   1.7   0.9
 23000 -44.5 -48.1  265  40 20   3.3   1.8 | -46.0 -50.8  245  29 15   2.7   1.5
 22000 -42.8 -45.0  260  37 19   6.2   3.4 | -43.8 -46.8  240  26 13   8.4   4.6
 21000 -41.0 -41.8  255  35 18   6.2   3.4 | -41.3 -42.3  230  23 12   8.4   4.6
 20000 -39.0 -38.2  250  32 16   9.4   5.1 | -38.7 -37.7  215  20 10   9.0   5.0
 19500 -37.6 -35.7  250  29 15   9.3   5.1 | -37.4 -35.3  215  19 10   9.0   4.9
 19000 -36.2 -33.2  255  27 14   9.3   5.1 | -36.0 -32.8  215  17  9   9.0   4.9
 18500 -34.8 -30.6  255  24 13   9.3   5.1 | -34.7 -30.5  210  16  8   9.0   4.9
 18000 -33.4 -28.1  255  22 11   9.3   5.1 | -33.3 -27.9  205  15  8   9.0   5.0
 17500 -32.1 -25.8  255  19 10   8.4   4.6 | -32.0 -25.6  200  14  7   8.4   4.6
 17000 -30.8 -23.4  255  15  8   8.5   4.7 | -30.8 -23.4  190  13  7   8.6   4.7
 16500 -29.6 -21.3  250  11  6   8.2   4.5 | -29.6 -21.3  180  13  7   6.9   3.8
 16000 -28.3 -18.9  245   9  5   8.1   4.5 | -28.6 -19.5  175  12  6   6.7   3.7
 15500 -26.6 -15.9  240   6  3   6.9   3.8 | -27.0 -16.6  165  11  6   7.4   4.1
 15000 -25.6 -14.1  235   5  2   7.0   3.9 | -25.9 -14.6  160  11  5   7.3   4.0
 14500 -24.5 -12.1  230   4  2   7.3   4.0 | -24.8 -12.6  150  10  5   7.8   4.3
 14000 -23.4 -10.1  220   3  1   7.3   4.0 | -23.7 -10.7  135  10  5   8.0   4.4
 13500 -22.3  -8.1  200   1  1   7.5   4.1 | -22.6  -8.7  125  10  5   5.5   3.0
 13000 -21.2  -6.2  135   1  1   7.4   4.1 | -21.8  -7.2  110   9  4   5.2   2.9
 12500 -20.1  -4.2  095   2  1   8.0   4.4 | -21.0  -5.8  095   8  4   7.1   3.9
 12000 -18.9  -2.0  090   4  2   8.1   4.5 | -19.9  -3.8  080   7  4   7.2   3.9
 11500 -17.7   0.1  085   6  3   8.0   4.4 | -18.7  -1.7  080   6  3   8.3   4.5
 11000 -16.5   2.3  075   9  4   8.4   4.6 | -17.5   0.5  095   6  3   8.9   4.9
 10500 -15.6   3.9  070  10  5   4.3   2.3 | -16.8   1.8  095   6  3   0.3   0.1
 10250 -15.2   4.6  065  10  5   5.6   3.1 | -16.8   1.8  090   6  3   1.5   0.8
 10000 -14.8   5.4  060  10  5   2.3   1.3 | -16.7   1.9  080   7  4   0.7   0.4
  9750 -14.7   5.5  055  10  5   3.6   2.0 | -16.6   2.1  080   8  4   1.4   0.8
  9500 -14.2   6.4  055   9  5   7.6   4.2 | -16.5   2.3  080   9  4   2.4   1.3
  9250 -13.7   7.3  060   9  4   6.8   3.7 | -16.3   2.7  075  10  5   2.2   1.2
  9000 -13.2   8.2  060   8  4   5.9   3.3 | -16.1   3.0  075  11  6   2.4   1.3
  8750 -12.8   9.0  065   8  4   6.2   3.4 | -15.9   3.4  070  12  6   3.6   2.0
  8500 -12.3   9.9  065   9  4   7.9   4.4 | -15.6   3.9  060  14  7   4.5   2.5
  8250 -11.7  10.9  070   9  5   7.6   4.2 | -15.2   4.6  050  15  8   5.2   2.9
  8000 -11.2  11.8  070  10  5   6.9   3.8 | -14.8   5.4  045  16  8   6.8   3.7
  7750 -10.7  12.7  070  12  6   5.6   3.1 | -14.2   6.4  045  17  9   8.1   4.5
  7500 -10.3  13.5  070  13  7   5.5   3.0 | -13.6   7.5  040  17  9   9.0   4.9
  7250 -10.0  14.0  065  14  7   3.7   2.0 | -12.9   8.8  035  17  9   8.7   4.8
  7000  -9.8  14.4  065  13  7   1.8   1.0 | -12.3   9.9  035  16  8   8.4   4.6
  6750  -9.6  14.7  060  12  6   2.0   1.1 | -11.7  10.9  030  16  8   8.3   4.6
  6500  -9.5  14.9  055  11  6  -0.2  -0.1 | -11.1  12.0  025  16  8   9.1   5.0
  6250  -9.6  14.7  045  10  5  -2.4  -1.3 | -10.4  13.3  025  15  8  10.0   5.5
  6000  -9.8  14.4  025   8  4  -3.3  -1.8 |  -9.6  14.7  020  14  7   9.8   5.4
  5750 -10.0  14.0  005   8  4  -1.2  -0.6 |  -8.9  16.0  020  13  7  10.0   5.5
  5500  -9.9  14.2  345   7  4   6.7   3.7 |  -8.1  17.4  015  12  6  10.8   6.0

           12/29/2014 at 1400 MST          |       12/29/2014 at 1700 MST
                                           |
K index... +5.0  LI... +5.0                | K index... +2.9  LI... +5.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.6
                                           |
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 -54.4 -65.9  275  59 30   2.9   1.6 | -55.0 -67.0  275  59 31   3.7   2.0
 45000 -49.9 -57.8  270  66 34   2.9   1.6 | -49.5 -57.1  270  58 30   3.7   2.0
 40000 -47.2 -53.0  275  66 34   1.6   0.9 | -47.4 -53.3  275  61 31   0.8   0.4
 38000 -46.2 -51.2  280  65 34   1.3   0.7 | -46.9 -52.4  280  63 32   0.5   0.3
 36000 -45.8 -50.4  275  65 34   0.7   0.4 | -46.9 -52.4  280  67 35  -0.1  -0.0
 34000 -45.3 -49.5  275  65 34   0.7   0.4 | -46.9 -52.4  275  72 37  -0.1  -0.0
 32000 -45.4 -49.7  275  63 33  -0.8  -0.4 | -46.7 -52.1  280  74 38   0.7   0.4
 30000 -45.9 -50.6  275  59 30  -0.8  -0.4 | -46.3 -51.3  280  73 38   0.7   0.4
 29000 -46.1 -51.0  275  57 29  -0.7  -0.4 | -46.1 -51.0  280  71 37   0.3   0.2
 28000 -46.4 -51.5  270  53 27  -0.8  -0.4 | -46.0 -50.8  280  67 34   0.3   0.2
 27000 -46.6 -51.9  270  49 25  -0.8  -0.4 | -45.9 -50.6  275  62 32   0.3   0.2
 26000 -46.8 -52.2  270  45 23  -0.8  -0.4 | -45.8 -50.4  275  57 29   0.3   0.2
 25000 -46.6 -51.9  265  39 20   1.1   0.6 | -45.8 -50.4  275  51 26   0.0   0.0
 24000 -46.3 -51.3  260  31 16   1.1   0.6 | -45.8 -50.4  270  44 23   0.0   0.0
 23000 -45.9 -50.6  255  25 13   1.8   1.0 | -45.8 -50.4  265  37 19   1.1   0.6
 22000 -43.9 -47.0  250  21 11   8.1   4.4 | -43.9 -47.0  260  31 16   7.5   4.1
 21000 -41.5 -42.7  245  19 10   8.1   4.4 | -41.7 -43.1  250  25 13   7.4   4.1
 20000 -39.0 -38.2  235  17  9   8.9   4.9 | -39.3 -38.7  245  20 10   9.1   5.0
 19500 -37.7 -35.9  230  17  9   8.9   4.9 | -38.0 -36.4  245  18  9   9.0   5.0
 19000 -36.3 -33.3  225  16  8   8.9   4.9 | -36.6 -33.9  250  17  9   9.0   5.0
 18500 -35.0 -31.0  225  16  8   8.9   4.9 | -35.3 -31.5  255  15  8   9.0   5.0
 18000 -33.7 -28.7  220  17  9   9.0   4.9 | -33.9 -29.0  260  14  7   9.1   5.0
 17500 -32.4 -26.3  210  16  8   8.0   4.4 | -32.6 -26.7  260  13  6   8.5   4.7
 17000 -31.2 -24.2  205  16  8   8.1   4.4 | -31.4 -24.5  260  11  6   8.6   4.7
 16500 -30.0 -22.0  195  15  8   7.7   4.2 | -30.1 -22.2  250   9  5   7.5   4.1
 16000 -28.9 -20.0  185  14  7   7.6   4.2 | -29.0 -20.2  235   8  4   7.3   4.0
 15500 -27.8 -18.0  180  14  7   7.4   4.1 | -28.0 -18.4  220   8  4   7.1   3.9
 15000 -26.1 -15.0  165  12  6   7.4   4.0 | -26.4 -15.5  200   8  4   6.9   3.8
 14500 -25.1 -13.2  155  11  5   6.7   3.7 | -25.4 -13.7  185   8  4   6.3   3.4
 14000 -24.1 -11.4  150  10  5   6.6   3.6 | -24.5 -12.1  180   8  4   6.3   3.5
 13500 -23.1  -9.6  145   9  4   7.1   3.9 | -23.6 -10.5  175   7  4   6.2   3.4
 13000 -22.0  -7.6  145   8  4   7.3   4.0 | -22.7  -8.9  165   6  3   6.2   3.4
 12500 -21.1  -6.0  145   7  4   5.3   2.9 | -21.8  -7.2  150   6  3   5.0   2.8
 12000 -20.3  -4.5  145   7  3   5.2   2.9 | -21.1  -6.0  135   6  3   5.2   2.8
 11500 -19.7  -3.5  140   6  3   2.8   1.6 | -20.5  -4.9  120   5  3   3.1   1.7
 11000 -19.3  -2.7  125   6  3   2.7   1.5 | -20.0  -4.0  105   4  2   3.3   1.8
 10500 -18.9  -2.0  115   5  3   2.8   1.5 | -19.7  -3.5  085   3  2   1.3   0.7
 10250 -18.6  -1.5  115   5  2   3.3   1.8 | -19.5  -3.1  065   3  1   1.7   0.9
 10000 -18.4  -1.1  115   4  2   1.4   0.8 | -19.4  -2.9  045   3  1   1.2   0.7
  9750 -18.4  -1.1  115   4  2   2.7   1.5 | -19.3  -2.7  035   3  2   2.3   1.3
  9500 -18.0  -0.4  100   4  2   6.3   3.4 | -19.1  -2.4  020   4  2   4.1   2.3
  9250 -17.5   0.5  085   4  2   6.6   3.6 | -18.8  -1.8  010   5  3   4.4   2.4
  9000 -17.1   1.2  075   4  2   5.2   2.9 | -18.4  -1.1  005   6  3   3.9   2.1
  8750 -16.7   1.9  060   5  3   4.8   2.6 | -18.2  -0.8  005   7  4   4.1   2.3
  8500 -16.3   2.7  050   6  3   6.5   3.6 | -17.8  -0.0  010   7  4   5.3   2.9
  8250 -15.8   3.6  040   7  4   6.3   3.5 | -17.4   0.7  020   7  4   5.6   3.1
  8000 -15.4   4.3  035   9  4   5.3   2.9 | -17.0   1.4  030   8  4   5.4   3.0
  7750 -15.0   5.0  035  11  5   5.1   2.8 | -16.6   2.1  040  10  5   5.7   3.1
  7500 -14.6   5.7  035  13  6   5.4   3.0 | -16.1   3.0  045  12  6   6.7   3.7
  7250 -14.2   6.4  030  14  7   7.1   3.9 | -15.6   3.9  045  13  7   8.7   4.7
  7000 -13.6   7.5  030  14  7   8.5   4.7 | -14.9   5.2  045  13  7   9.5   5.2
  6750 -13.0   8.6  030  14  7   7.7   4.2 | -14.2   6.4  045  13  7   9.4   5.2
  6500 -12.4   9.7  025  14  7   9.1   5.0 | -13.5   7.7  045  12  6   9.6   5.3
  6250 -11.6  11.1  025  14  7  10.7   5.9 | -12.8   9.0  045  12  6   9.6   5.3
  6000 -10.9  12.4  025  13  7  10.3   5.6 | -12.1  10.2  040  11  6   9.5   5.2
  5750 -10.1  13.8  020  12  6  10.7   5.9 | -11.4  11.5  040  10  5  10.0   5.5
  5500  -9.3  15.3  020  11  6  12.4   6.8 | -10.6  12.9  040   9  5  10.8   6.0
________________________________________________________________________________

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



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