December: New Years Eve Outlook

[jeff]

I'm just going to go out on a limb here.... In Wharton County and having a parade in El Campo, any chance to see a lil snow flurry? Also, will rain be an issue between 5-9pm? I asked a day or so ago, but want to hear your thoughts now that we are getting close.

Temperatures a few thousand feet above the surface will be in the 40's. Only the lowest 1000 ft or so will be "cold" so there will be no snow and sleet even seems remote. Main threat is freezing rain and mainly NW of a line from Columbus to The Woodlands to Livingston.

[Ptarmigan]

I saw at NWS Houston and they forecast freezing drizzle on Friday night to Saturday morning. The past two winters were warm. This winter looks to be a cold one.

[Andrew]

A little late but 20z Sounding today from KCLL:

[jeff]

A little late but 20z Sounding today from KCLL:

Look at that warm nose. A very shallow cold layer with temperatures up around 55-58 degrees around 4000 ft

[Andrew]

A little late but 20z Sounding today from KCLL:

Look at that warm nose. A very shallow cold layer with temperatures up around 55-58 degrees around 4000 ft

Yea when we loaded the data up and saw the warm nose it was pretty incredible. I haven't seen an inversion like that in a long time. Shows just how shallow the front is. We will see if it is degraded at all tomorrow when we launch again.

[cristina6871]

and what does the warm nose mean? or do I want to know?

[Andrew]

and what does the warm nose mean? or do I want to know?

If you look at the skew-t above (that i posted) and if you notice around 900mb how the green (and red but it is covered up by the green line) goes straight to the right, that is referred to the inversion or warm nose. Basically means that temp rises with height for that period instead of decreasing like normally.

[cristina6871]

okay....so what does that mean for the cold?

[srainhoutx]

Update from Jeff: (although he already has been posting about the information, so we already know...Thanks Jeff... )

Cold arctic air mass pouring into the region this evening.

800pm temperatures have fallen to 34-46 from College Station to Huntsville with upstream temperatures 30-32 at Waco and Temple and 28-31 at Dallas. TX TECH model clearly shows cold air intrusion from the NNE between I-35 and I-45 this evening and this appears to be what is happening as one thrust of the arctic air pours down this corridor. Dewpoint at Caldwell, TX has fallen to 30 with an air temperature of 34. Given the expected onset of rainfall this evening, there is some potential for surface temperature to wet bulb toward the dewpoint and along with continued cold air advection could bring the surface temperature to or below 32 overnight near/NW of College Station.

With all that said, the HRRR soundings for CLL show a massive warm nose above the surface cold dome which is only about 1000ft deep. Temperatures warm to almost 60 degrees at 4000-5000ft so rain falling will be “very warm” and even if surface temperatures fall to freezing tonight 30-32 do not expect much icing over our NW counties with such warm temperatures aloft. Will see this warm layer begin to cool on Friday into Friday night, but still expected to be in the 40-50 degree range while the surface cold dome deepens to about 2000 ft by Friday evening.

Also of note is the 18Z GFS which now brings IAH to freezing on Saturday morning around 900am and keeps the temperature between 31-33 into Sunday afternoon. This suggest the potential for the freezing line to penetrate deeper into Harris County over the weekend with some possible elevated icing of tree limbs and power lines. Once again we will be fighting a lot of negatives: warm air aloft, warm ground temperatures, and light rainfall amounts which should not result in ice accumulation greater than .01-.05 of an inch Saturday night into Sunday morning.

Note: Major ice/sleet storm underway over north TX with road conditions becoming extremely hazardous. Numerous highway bridges are ice covered and travel from Waco  northward to DFW into OK will become extremely hazardous if not impossible overnight tonight as heavy freezing rain and significant icing develops. Ice accumulation of up to .50 of an inch is possible over N into NE TX resulting is extensive tree damage and power outages. A faster change to sleet or great mix ratio could help cut down on the ice accumulation, but things are looking pretty rough in this part of the state into this weekend and ice will remain on the ground likely into next week as very cold temperatures remain locked in place.  

[skidog40]

cold air coming in or seeping through and slow moving moisture setting up to be a ...........

[Ptarmigan]

December is starting out cold. Last December was quite warm. If we stay cool for December, it could be the coolest since December 2009, which is one of the coolest Decembers on record.
http://www.srh.noaa.gov/productview.php?pil=HGXCF6IAH

December 2012

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437
CXUS54 KHGX 011420
CF6IAH
PRELIMINARY LOCAL CLIMATOLOGICAL DATA (WS FORM: F-6)

                                          STATION:   HOUSTON INTERCONTINENTAL
                                          MONTH:     DECEMBER
                                          YEAR:      2012
                                          LATITUDE:   29 58 N
                                          LONGITUDE:  95 21 W

  TEMPERATURE IN F:       :PCPN:    SNOW:  WIND      :SUNSHINE: SKY     :PK WND
================================================================================
1   2   3   4   5  6A  6B    7    8   9   10  11  12  13   14  15   16   17  18
                                     12Z  AVG MX 2MIN
DY MAX MIN AVG DEP HDD CDD  WTR  SNW DPTH SPD SPD DIR MIN PSBL S-S WX    SPD DR
================================================================================

 1  83  63  73  16   0   8    T  0.0    0  8.1 21 150   M    M   6 1      25 150
 2  84  59  72  15   0   7 0.00  0.0    0  6.6 17 150   M    M   4 12     23 130
 3  82  65  74  17   0   9 0.08  0.0    0  7.1 15 140   M    M   7 1      20 210
 4  83  59  71  15   0   6 0.07  0.0    0  3.8 14 330   M    M   9 1238   22  50
 5  66  55  61   5   4   0 0.00  0.0    0  5.4  9 350   M    M   7 18     12  30
 6  69  56  63   7   2   0 0.00  0.0    0  6.6 15 130   M    M   8 1      20 130
 7  81  54  68  12   0   3 0.00  0.0    0  4.0 14 130   M    M   7 12     18 200
 8  83  62  73  17   0   8 0.00  0.0    0  5.3 14 170   M    M   6 1      20 170
 9  81  59  70  15   0   5 0.06  0.0    0  6.0 18 330   M    M   7 13     23 320
10  59  38  49  -6  16   0 0.19    M    0 14.1 30 340   M    M   6 13     39 340
11  55  32  44 -11  21   0 0.00  0.0    0  5.2 15 340   M    M   4        17 340
12  61  34  48  -7  17   0 0.00  0.0    0  2.7  9  60   M    M   1        15 150
13  64  32  48  -7  17   0 0.00  0.0    0  4.9 13 110   M    M   2        17 110
14  70  48  59   5   6   0    T    M    0  9.6 21 130   M    M   9        25 130
15  81  68  75  21   0  10    T  0.0    0  8.1 17 170   M    M   9 1      23 160
16  72  59  66  12   0   1 1.58  0.0    0  3.8 20 270   M    M  10 123    30  30
17  69  45  57   3   8   0 0.00  0.0    0  5.6 17 310   M    M   3 12     22 320
18  80  43  62   8   3   0 0.00  0.0    0  5.5 14 170   M    M   1        18 160
19  81  64  73  19   0   8 0.00  0.0    0 11.5 23 160   M    M   6        33 160
20  75  40  58   4   7   0 0.06    M    0 14.6 31 330   M    M   4 38     44 310
21  62  32  47  -7  18   0 0.00  0.0    0  2.4  8 230   M    M   4        12  20
22  69  33  51  -2  14   0 0.00  0.0    0  5.2 18 150   M    M   5        26 140
23  75  60  68  15   0   3 0.00  0.0    0  7.1 17 220   M    M   8        24 230
24  75  58  67  14   0   2    T  0.0    0  4.4 13 230   M    M   5 1      21 230
25  77  36  57   4   8   0 0.04    M    0 15.9 39 310   M    M   6 18     51 310
26  47  33  40 -13  25   0 0.00  0.0    0  9.9 23 310   M    M   7        31 330
27  53  31  42 -11  23   0 0.08    M    0  7.3 15 100   M    M   9 1      17  80
28  60  43  52  -1  13   0 0.12    M    0 11.3 25 340   M    M   9 1      32 310
29  51  34  43 -10  22   0 0.00  0.0    0  9.5 22 340   M    M   7        29 350
30  51  30  41 -12  24   0 0.00  0.0    0  6.3 15 140   M    M   6        18 130
31  67  46  57   4   8   0 0.57    M    0  7.4 15 130   M    M  10 12     20 130
================================================================================
SM 2166 1471       256  70  2.85     0.0 225.2          M      192
================================================================================
AV 69.9 47.5                               7.3 FASTST   M    M   6    MAX(MPH)
                                 MISC ---->  # 39 310               # 51  310
================================================================================

December 2011

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000
CXUS54 KHGX 101432
CF6IAH
PRELIMINARY LOCAL CLIMATOLOGICAL DATA (WS FORM: F-6)

                                          STATION:   HOUSTON INTERCONTINENTAL
                                          MONTH:     DECEMBER
                                          YEAR:      2011
                                          LATITUDE:   29 58 N
                                          LONGITUDE:  95 21 W

  TEMPERATURE IN F:       :PCPN:    SNOW:  WIND      :SUNSHINE: SKY     :PK WND
================================================================================
1   2   3   4   5  6A  6B    7    8   9   10  11  12  13   14  15   16   17  18
                                     12Z  AVG MX 2MIN
DY MAX MIN AVG DEP HDD CDD  WTR  SNW DPTH SPD SPD DIR MIN PSBL S-S WX    SPD DR
================================================================================

 1  73  39  56  -1   9   0 0.00  0.0    0  9.9 16 110   M    M   3 1      22 120
 2  71  53  62   5   3   0 0.00  0.0    0 10.6 15 110   M    M   6 1      20 110
 3  77  61  69  12   0   4 0.01  0.0    0 13.0 26 160   M    M   8        35 160
 4  72  55  64   8   1   0 0.31  0.0    0  9.1 16 360   M    M   9 1      20 360
 5  55  44  50  -6  15   0 0.95    M    0 11.9 17 320   M    M  10 13     23 330
 6  44  34  39 -17  26   0    T    M    0 11.8 14 300   M    M   9 1      20 300
 7  50  29  40 -16  25   0 0.00  0.0    0  6.4  2 310   M    M   3         2 190
 8  57  29  43 -13  22   0 0.00  0.0    0  5.6 14 140   M    M   5 8      18 130
 9  60  47  54  -1  11   0    T    M    0  6.9 12  60   M    M  10 8      14  70
10  58  47  53  -2  12   0 0.00  0.0    0  7.9 17  60   M    M   9        21  50
11  57  40  49  -6  16   0    T    M    0  7.0  9  90   M    M   6        12 100
12  65  43  54  -1  11   0 0.00  0.0    0  7.9 15 120   M    M   7        18 110
13  65  56  61   6   4   0 0.00  0.0    0 10.4 17 110   M    M  10 1      21 110
14  77  63  70  16   0   5    T  0.0    0 13.5 24 140   M    M   9 18     28 140
15  77  66  72  18   0   7 0.10  0.0    0  6.2 13 120   M    M   8 12     15 120
16  68  52  60   6   5   0 0.01  0.0    0 13.4 16  20   M    M  10 12     21  40
17  64  50  57   3   8   0 0.00  0.0    0  8.3 18  10   M    M   7        21  10
18  65  44  55   1  10   0 0.00  0.0    0  6.2 14 150   M    M   6        17 140
19  72  51  62   8   3   0 0.06  0.0    0 12.3 28 140   M    M   8 18     33 140
20  70  50  60   6   5   0 0.33  0.0    0  7.2  5 330   M    M   8 13      6 320
21  60  43  52  -2  13   0 0.01    M    0  3.9  9  40   M    M   7 138    12  30
22  57  49  53   0  12   0 1.52    M    0  5.3 17 300   M    M   8 138    28 330
23  56  48  52  -1  13   0    T    M    0 10.0 17  40   M    M  10        21  40
24  51  43  47  -6  18   0 0.79    M    0 12.0 15  20   M    M  10 128    20  20
25  48  42  45  -8  20   0 0.19    M    0  8.6  9 320   M    M  10 18     12 320
26  51  40  46  -7  19   0    T    M    0  5.0  6 210   M    M   7 1       8 210
27  62  37  50  -3  15   0 0.00  0.0    0  3.4  3 240   M    M   0 1       5 320
28  66  34  50  -3  15   0 0.00  0.0    0  5.1  9 140   M    M   3 1      10 140
29  63  43  53   0  12   0 0.00  0.0    0  1.2  5 180   M    M   6 128     6 180
30  73  40  57   4   8   0 0.00  0.0    0  2.6  8 160   M    M   2 1       9 100
31  75  55  65  12   0   0 0.00  0.0    0  5.3 16 190   M    M   9 12     21 200
================================================================================
SM 1959 1427       331  16  4.28     0.0 247.9          M      223
================================================================================
AV 63.2 46.0                               8.0 FASTST   M    M   7    MAX(MPH)
                                 MISC ---->  # 28 140               # 35  160
================================================================================

December 2010

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000
CXUS54 KHGX 011423
CF6IAH
PRELIMINARY LOCAL CLIMATOLOGICAL DATA (WS FORM: F-6)

                                          STATION:   HOUSTON INTERCONTINENTAL
                                          MONTH:     DECEMBER
                                          YEAR:      2010
                                          LATITUDE:   29 58 N
                                          LONGITUDE:  95 21 W

  TEMPERATURE IN F:       :PCPN:    SNOW:  WIND      :SUNSHINE: SKY     :PK WND
================================================================================
1   2   3   4   5  6A  6B    7    8   9   10  11  12  13   14  15   16   17  18
                                     12Z  AVG MX 2MIN
DY MAX MIN AVG DEP HDD CDD  WTR  SNW DPTH SPD SPD DIR MIN PSBL S-S WX    SPD DR
================================================================================

 1  64  32  48  -9  17   0 0.00  0.0    0  3.2 12 210   M    M   1        17 300
 2  71  37  54  -2  11   0 0.00  0.0    0  4.3 15 140   M    M   2        18 180
 3  76  47  62   6   3   0 0.00  0.0    0  4.6 16 130   M    M   3 1      20 130
 4  80  58  69  13   0   4 0.00  0.0    0  6.7 16 250   M    M   5        23 270
 5  62  42  52  -4  13   0 0.00  0.0    0 11.0 21  20   M    M   6        25  10
 6  57  35  46  -9  19   0 0.00  0.0    0  2.7 10 360   M    M   3        15  10
 7  62  33  48  -7  17   0 0.05    M    0  6.3 16 130   M    M   6 18     22 130
 8  53  37  45 -10  20   0    T    M    0  9.8 20  50   M    M   8 1      25  50
 9  63  31  47  -8  18   0 0.00  0.0    0  5.2 16 160   M    M   3 1      21 150
10  75  43  59   4   6   0 0.00  0.0    0  6.0 17 160   M    M   5 1      23 170
11  77  54  66  12   0   1 0.00  0.0    0 11.0 29 350   M    M   5        38 350
12  57  38  48  -6  17   0 0.00  0.0    0 15.6 22 350   M    M   2        38 340
13  58  31  45  -9  20   0 0.00  0.0    0  4.1 15 140   M    M   0        18 150
14  71  37  54   0  11   0 0.00  0.0    0  7.6 18 170   M    M   3        26 170
15  77  52  65  11   0   0 0.00  0.0    0  9.0 21 210   M    M   5 1      37 190
16  72  57  65  12   0   0 0.00  0.0    0  8.0 15 340   M    M   7        22 230
17  60  47  54   1  11   0    T    M    0  9.9 17 360   M    M   9        21  10
18  60  38  49  -4  16   0 0.00  0.0    0  5.6 13  30   M    M   6        16  20
19  62  37  50  -3  15   0 0.00  0.0    0  7.3 18 140   M    M   3        23 120
20  78  56  67  14   0   2 0.00  0.0    0  9.0 16 170   M    M   8        25 220
21  82  67  75  22   0  10 0.00  0.0    0  8.5 16 230   M    M   6        24 230
22  76  64  70  17   0   5 0.00  0.0    0  6.0 14  20   M    M  10 18     17  20
23  64  50  57   5   8   0 0.00  0.0    0  9.7 15  90   M    M   9        18  80
24  67  46  57   5   8   0 1.03    M    0 12.1 25 340   M    M   9 13     32 340
25  46  37  42 -10  23   0    T    M    0 17.2 29 350   M    M  10 1      37 360
26  50  30  40 -12  25   0 0.00  0.0    0  5.5 13 350   M    M   1        17 310
27  53  29  41 -11  24   0 0.00  0.0    0  9.2 20 140   M    M   5        22 120
28  64  48  56   4   9   0 0.00  0.0    0 10.4 18 140   M    M   9        22 140
29  64  56  60   8   5   0 1.96  0.0    0  9.0 26 150   M    M  10 13     30 150
30  74  57  66  14   0   1    T  0.0    0 11.3 21 160   M    M  10 128    28 160
31  76  60  68  16   0   3    T  0.0    0  9.3 21 350   M    M  10 18     24 350
================================================================================
SM 2051 1386       316  26  3.04     0.0 255.1          M      179
================================================================================
AV 66.2 44.7                               8.2 FASTST   M    M   6    MAX(MPH)
                                 MISC ---->  # 29 350               # 38  350
================================================================================

December 2009

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000
CXUS54 KHGX 011415
CF6IAH
PRELIMINARY LOCAL CLIMATOLOGICAL DATA (WS FORM: F-6)

                                          STATION:   HOUSTON INTERCONTINENTAL
                                          MONTH:     DECEMBER
                                          YEAR:      2009
                                          LATITUDE:   29 58 N
                                          LONGITUDE:  95 21 W

  TEMPERATURE IN F:       :PCPN:    SNOW:  WIND      :SUNSHINE: SKY     :PK WND
================================================================================
1   2   3   4   5  6A  6B    7    8   9   10  11  12  13   14  15   16   17  18
                                     12Z  AVG MX 2MIN
DY MAX MIN AVG DEP HDD CDD  WTR  SNW DPTH SPD SPD DIR MIN PSBL S-S WX    SPD DR
================================================================================

 1  52  48  50  -7  15   0 1.38    M    0 10.4 28  60   M    M  10 1      32  60
 2  52  46  49  -7  16   0 0.00  0.0    0 10.8 23 320   M    M  10 1      31 310
 3  56  39  48  -8  17   0 0.00  0.0    0  7.2 16  10   M    M   5        21  10
 4  46  31  39 -17  26   0 0.22  1.0    1  8.8 21  10   M    M   8 12     25  10
 5  49  26  38 -18  27   0 0.00  0.0    0  3.6 15 100   M    M   3        17 100
 6  59  36  48  -7  17   0 0.15    M    0 10.3 17 120   M    M  10 1      22 120
 7  59  55  57   2   8   0 0.44  0.0    0  7.3 16  40   M    M  10 12     18  40
 8  77  56  67  12   0   2 0.02  0.0    0  6.9 18 210   M    M   9 128    28 210
 9  63  39  51  -4  14   0 0.00  0.0    0 10.2 24 350   M    M   7 12     30 350
10  53  34  44 -11  21   0 0.00  0.0    0  9.1 15  50   M    M   8        17  40
11  51  44  48  -6  17   0 0.47    M    0 10.3 23 100   M    M  10 13     26 100
12  56  46  51  -3  14   0 0.71    M    0  5.2 18  90   M    M  10 12     21  90
13  54  48  51  -3  14   0 0.00  0.0    0  4.6 12 140   M    M  10 12     14 130
14  63  53  58   4   7   0 0.19  0.0    0  3.5  8  70   M    M  10 12     12 360
15  63  48  56   2   9   0 0.27    M    0 13.8 22  30   M    M  10 12     30  20
16  56  43  50  -3  15   0    T    M    0  9.6 16  40   M    M   9        21  40
17  51  45  48  -5  17   0 0.55    M    0  8.0 14  30   M    M   9 1      17  20
18  66  41  54   1  11   0 0.00  0.0    0  6.5 14 310   M    M   2        17 310
19  63  42  53   0  12   0 0.00  0.0    0  6.9 20 340   M    M   2        23 340
20  60  34  47  -6  18   0 0.00  0.0    0  2.5  8 360   M    M   0        12 360
21  68  36  52  -1  13   0 0.00  0.0    0  5.8 16 140   M    M   3 1      20 130
22  71  49  60   7   5   0 0.03    M    0  9.3 23 160   M    M   9 1      30 160
23  76  66  71  19   0   6 0.01  0.0    0 13.3 28 170   M    M   9        36 160
24  72  37  55   3  10   0 0.15    M    0 17.2 30 310   M    M   8 13     46 230
25  49  32  41 -11  24   0 0.00  0.0    0  6.5 21 300   M    M   2        32 290
26  53  35  44  -8  21   0 0.00  0.0    0  2.9 10  90   M    M   8        13 110
27  59  35  47  -5  18   0 0.00  0.0    0  5.7 15 320   M    M   2        20 300
28  54  34  44  -8  21   0 0.00  0.0    0  7.4 16 360   M    M   2        25 340
29  48  33  41 -11  24   0 0.16    M    0  4.8 14 100   M    M   8 1      17 100
30  54  43  49  -3  16   0 0.69    M    0  5.8 12 310   M    M  10 1      15  10
31  58  47  53   1  12   0 0.00  0.0    0  5.1 24 340   M    M   9 128    32 350
================================================================================
SM 1811 1301       459   8  5.44     1.0 239.3          M      222
================================================================================
AV 58.4 42.0                               7.7 FASTST   M    M   7    MAX(MPH)
                                 MISC ---->  # 30 310               # 46  230
================================================================================

December 2008

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000
CXUS54 KHGX 011415
CF6IAH
PRELIMINARY LOCAL CLIMATOLOGICAL DATA (WS FORM: F-6)

                                          STATION:   HOUSTON
                                          MONTH:     DECEMBER
                                          YEAR:      2008
                                          LATITUDE:   29 58 N
                                          LONGITUDE:  95 21 W

  TEMPERATURE IN F:       :PCPN:    SNOW:  WIND      :SUNSHINE: SKY     :PK WND
================================================================================
1   2   3   4   5  6A  6B    7    8   9   10  11  12  13   14  15   16   17  18
                                     12Z  AVG MX 2MIN
DY MAX MIN AVG DEP HDD CDD  WTR  SNW DPTH SPD SPD DIR MIN PSBL S-S WX    SPD DR
================================================================================

 1  59  36  48  -9  17   0 0.00  0.0    0  9.8 26 310   M    M   4        37 310
 2  69  34  52  -4  13   0 0.00  0.0    0  8.1 18 170   M    M   2        22 160
 3  79  54  67  11   0   2 0.17  0.0    0 12.2 16 330   M    M   8 13     20 340
 4  57  43  50  -6  15   0 0.00  0.0    0 13.5 22 360   M    M   7        30  10
 5  54  36  45 -11  20   0 0.00  0.0    0  6.5 17  40   M    M   7        20  40
 6  64  36  50  -5  15   0 0.00  0.0    0  2.5 10 310   M    M   3        17 330
 7  65  38  52  -3  13   0 0.00  0.0    0  5.6 16 140   M    M   1        20 130
 8  72  45  59   4   6   0    T    M    0 11.9 23 160   M    M   8        28 160
 9  78  43  61   6   4   0 0.30    M    0 12.4 29 350   M    M   8 138    32 350
10  43  32  38 -17  27   0 0.31  1.4    0 12.7 24 340   M    M  10 18     30 330
11  56  33  45  -9  20   0    T  0.0    0 10.8 22 340   M    M   3        26 330
12  64  32  48  -6  17   0 0.00  0.0    0  3.5  6 160   M    M   2         7 160
13  72  38  55   1  10   0 0.01  0.0    0 10.8 29 150   M    M   8        35 150
14  75  62  69  15   0   4    T  0.0    0 11.3 22 170   M    M   7        29 150
15  64  39  52  -2  13   0 0.04  0.0    0 11.5 22 360   M    M   9 128    25  10
16  44  37  41 -12  24   0 0.01  0.0    0  6.4 17 360   M    M  10 12     21 360
17  64  44  54   1  11   0 0.03  0.0    0  5.6 10  90   M    M   9 128    12 100
18  75  59  67  14   0   2 0.03  0.0    0  9.8 18 170   M    M   9 128    22 160
19  80  69  75  22   0  10    T  0.0    0  6.5 13 190   M    M   9 18     18 180
20  77  64  71  18   0   6 0.00  0.0    0  6.9 16 340   M    M   9 18     22 210
21  64  42  53   0  12   0 0.00  0.0    0 17.3 29  20   M    M  10        35  50
22  42  31  37 -16  28   0    T    M    0 12.2 22 360   M    M  10 6      25 360
23  74  40  57   5   8   0 0.18    M    0  8.9 23 200   M    M  10 18     33 210
24  72  59  66  14   0   1 0.11  0.0    0  6.9 15 320   M    M   9 1      20 280
25  74  60  67  15   0   2 0.00  0.0    0  7.4 18 160   M    M  10 18     23 160
26  77  70  74  22   0   9 0.02  0.0    0 13.9 24 160   M    M   9 1      30 160
27  78  56  67  15   0   2 0.08  0.0    0 12.0 26 330   M    M  10 1      31 330
28  57  43  50  -2  15   0 0.39    M    0  8.1 18 360   M    M   9 13     22  10
29  66  41  54   2  11   0 0.00  0.0    0  2.6  9  40   M    M   1        12 360
30  70  37  54   2  11   0 0.00  0.0    0  2.3  9 160   M    M   4 1      12 220
31  66  45  56   4   9   0 0.00  0.0    0  8.2 21  40   M    M   6 1      26  50
================================================================================
SM 2051 1398       319  38  1.68     1.4 278.1          M      221
================================================================================
AV 66.2 45.1                               9.0 FASTST   M    M   7    MAX(MPH)
                                 MISC ---->  # 29 350               # 37  310
================================================================================

[Ptarmigan]

If Houston sees freezing rain, it would be the first time since 2011.
http://www.wxresearch.com/almanac/houice.htm

It goes back to 1961. I am sure Houston has had freezing rain before 1961. The earliest is November 28-29, 1976. The latest is February 24, 1965. The latest snowfall in Houston is March 10-11, 1932.

http://www.wxresearch.com/almanac/snowhou.htm

[Paul Robison]

Update from Jeff: (although he already has been posting about the information, so we already know...Thanks Jeff... )

Cold arctic air mass pouring into the region this evening.

800pm temperatures have fallen to 34-46 from College Station to Huntsville with upstream temperatures 30-32 at Waco and Temple and 28-31 at Dallas. TX TECH model clearly shows cold air intrusion from the NNE between I-35 and I-45 this evening and this appears to be what is happening as one thrust of the arctic air pours down this corridor. Dewpoint at Caldwell, TX has fallen to 30 with an air temperature of 34. Given the expected onset of rainfall this evening, there is some potential for surface temperature to wet bulb toward the dewpoint and along with continued cold air advection could bring the surface temperature to or below 32 overnight near/NW of College Station.

With all that said, the HRRR soundings for CLL show a massive warm nose above the surface cold dome which is only about 1000ft deep. Temperatures warm to almost 60 degrees at 4000-5000ft so rain falling will be “very warm” and even if surface temperatures fall to freezing tonight 30-32 do not expect much icing over our NW counties with such warm temperatures aloft. Will see this warm layer begin to cool on Friday into Friday night, but still expected to be in the 40-50 degree range while the surface cold dome deepens to about 2000 ft by Friday evening.

Also of note is the 18Z GFS which now brings IAH to freezing on Saturday morning around 900am and keeps the temperature between 31-33 into Sunday afternoon. This suggest the potential for the freezing line to penetrate deeper into Harris County over the weekend with some possible elevated icing of tree limbs and power lines. Once again we will be fighting a lot of negatives: warm air aloft, warm ground temperatures, and light rainfall amounts which should not result in ice accumulation greater than .01-.05 of an inch Saturday night into Sunday morning.

Note: Major ice/sleet storm underway over north TX with road conditions becoming extremely hazardous. Numerous highway bridges are ice covered and travel from Waco  northward to DFW into OK will become extremely hazardous if not impossible overnight tonight as heavy freezing rain and significant icing develops. Ice accumulation of up to .50 of an inch is possible over N into NE TX resulting is extensive tree damage and power outages. A faster change to sleet or great mix ratio could help cut down on the ice accumulation, but things are looking pretty rough in this part of the state into this weekend and ice will remain on the ground likely into next week as very cold temperatures remain locked in place.  

Good heavens, srainhoutex! Is Jeff saying we're looking at sporadic power outages across the Houston area, just as in Dallas?

[Andrew]

Update from Jeff: (although he already has been posting about the information, so we already know...Thanks Jeff... )

Cold arctic air mass pouring into the region this evening.

800pm temperatures have fallen to 34-46 from College Station to Huntsville with upstream temperatures 30-32 at Waco and Temple and 28-31 at Dallas. TX TECH model clearly shows cold air intrusion from the NNE between I-35 and I-45 this evening and this appears to be what is happening as one thrust of the arctic air pours down this corridor. Dewpoint at Caldwell, TX has fallen to 30 with an air temperature of 34. Given the expected onset of rainfall this evening, there is some potential for surface temperature to wet bulb toward the dewpoint and along with continued cold air advection could bring the surface temperature to or below 32 overnight near/NW of College Station.

With all that said, the HRRR soundings for CLL show a massive warm nose above the surface cold dome which is only about 1000ft deep. Temperatures warm to almost 60 degrees at 4000-5000ft so rain falling will be “very warm” and even if surface temperatures fall to freezing tonight 30-32 do not expect much icing over our NW counties with such warm temperatures aloft. Will see this warm layer begin to cool on Friday into Friday night, but still expected to be in the 40-50 degree range while the surface cold dome deepens to about 2000 ft by Friday evening.

Also of note is the 18Z GFS which now brings IAH to freezing on Saturday morning around 900am and keeps the temperature between 31-33 into Sunday afternoon. This suggest the potential for the freezing line to penetrate deeper into Harris County over the weekend with some possible elevated icing of tree limbs and power lines. Once again we will be fighting a lot of negatives: warm air aloft, warm ground temperatures, and light rainfall amounts which should not result in ice accumulation greater than .01-.05 of an inch Saturday night into Sunday morning.

Note: Major ice/sleet storm underway over north TX with road conditions becoming extremely hazardous. Numerous highway bridges are ice covered and travel from Waco  northward to DFW into OK will become extremely hazardous if not impossible overnight tonight as heavy freezing rain and significant icing develops. Ice accumulation of up to .50 of an inch is possible over N into NE TX resulting is extensive tree damage and power outages. A faster change to sleet or great mix ratio could help cut down on the ice accumulation, but things are looking pretty rough in this part of the state into this weekend and ice will remain on the ground likely into next week as very cold temperatures remain locked in place.  

Good heavens, srainhoutex! Is Jeff saying we're looking at sporadic power outages across the Houston area, just as in Dallas?

No.

[Belmer]

Quick update here in the OKC/Norman area:

Most all local mets said that the second wave of this precip would be a couple hours of sleet, then sleet/snow, then turning all into snow for much of the area this evening into overnight. I would agree as the sounding showed still a small inversion. Well as soon as the precip came into Oklahoma, it has pretty much just been snow. I suspect that higher accumulation totals will result of this because of it starting off as snow first instead of a couple hours of sleet.
Here in Norman, been snowing heavy now for about an hour an half or so. Unfortunately, (for me because I wanted to have a snowball fight and build a snowman) it is the light powdery snow. Snow is blowing pretty hard as well causing some pretty good drifting in the corners of buildings. Also really building up on the streets and cars.

Looks to be a long night for northern areas of Texas; especially where sleet and freezing rain is falling as accumulation could be quite significant. Very dangerous situation happening for them.

[srainhoutx]

Winter Weather Advisory
URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
300 AM CST FRI DEC 6 2013

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 3 PM...

.AREAS OF MIXED PRECIPITATION ARE BEGINNING TO DEVELOP ACROSS THE
REGION. ALTHOUGH SURFACE READINGS SHOULD REMAIN JUST ABOVE
FREEZING FOR MOST LOCATIONS...FREEZING TEMPERATURES A GOOD
POSSIBILITY ON ELEVATED STRUCTURES SUCH AS BRIDGES AND OVERPASSES.
IN ADDITION TO SLEET...ANY DRIZZLE AND LIGHT RAIN WILL FREEZE ON
CONTACT WHERE TEMPERATURES ARE BELOW FREEZING AND BEGIN PRODUCING
MINOR ACCUMULATIONS. BRIDGES AND OVERPASSES COULD BECOME HAZARDOUS.
TRAVEL WITH CAUTION THROUGH THE ADVISORY AREA. PRECIPITATION
SHOULD COME TO AN END FROM THE NORTHWEST DURING THE EARLY
AFTERNOON HOURS.

TXZ163-176-177-195>198-061700-
/O.NEW.KHGX.WW.Y.0001.131206T0900Z-131206T2100Z/
BRAZOS-BURLESON-GRIMES-HOUSTON-MADISON-WALKER-WASHINGTON-
INCLUDING THE CITIES OF...BRENHAM...BRYAN...CALDWELL...
COLLEGE STATION...CROCKETT...HUNTSVILLE...LAKE SOMERVILLE...
MADISONVILLE...NAVASOTA
300 AM CST FRI DEC 6 2013

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 3 PM CST THIS
AFTERNOON...

THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A
WINTER WEATHER ADVISORY FOR NORTHERN PARTS OF SOUTHEAST
TEXAS...WHICH IS IN EFFECT UNTIL 3 PM CST THIS AFTERNOON.

* TIMING...THROUGH 3 PM CST.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SLEET OR FREEZING
RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

ROADS...BRIDGES...AND OVERPASSES IN THE WARNING AREA ARE
SLICK AND HAZARDOUS. ACCUMULATION OF ICE ON ROADWAYS...BRIDGES AND
OVERPASSES WILL MAKE TRAVEL TREACHEROUS

[srainhoutx]

A major Winter Storm is impacting our Region this morning and will continue to bring wintry weather with a variety of precipitation in the form of very cold rain, freezing rain and drizzle, sleet and even some snow across much of the Lone Star State extending well to our W into Southern California and on E into the Mid Atlantic States.

The Arctic Outbreak has entrenched a large geographical area and is creating widespread societal impacts with a large area for freezing rain, sleet and snow that is causing expansive areas of power failures extending from Texas to Kentucky and will likely spread further E toward the Washington DC area as well as parts of the NE.

A full latitude trough extends from Eastern Alaska and the Canadian Prairies straight South into Mexico and Texas. Embedded short wave (Upper air disturbances) continue to ride S along the West Coast of California into the base of the trough and tap abundant tropical moisture from the Eastern Pacific. This tropical connection has led to a SW flow over Mexico and Texas where surface temperatures are near or below freezing while a warmer layer above 1000 feet up to about 5000 feet continues to spread across the Region.

The latest data is suggesting that freezing rain and perhaps some sleet will spread further South into S Central/SE and E Texas and possibly portions of SW Louisiana during the overnight hours of Friday into early Saturday. The 03Z SPC SREF ensemble mean is suggesting a freezing rain potential into the Houston Metro area. The 06Z GFS data suggest everything from freezing rain to snow could be possible mainly along a Columbus to Waller to Conroe into Liberty line. It is also noteworthy that the 06Z GFS data suggests that temps at or just below freezing may be possible at IAH. The main threat will be potential icing of elevated roadways/overpasses as well as trees and power lines. While the precipitation is expected to remain light, caution is advised while traveling during the overnight hours. Stay Tuned!

The attachment 12062013 03Z SPC SREF Mean SREF_LIKELY__f030.gif is no longer available

[unome]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
436 AM CST FRI DEC 6 2013

.DISCUSSION...
EQUIPMENT ISSUES. HERE`S PRELIM NUMBERS. FULL DISCUSSION OUT AS
SOON AS POSSIBLE. OVERALL NO BIG CHANGES. MAIN FREEZING PRECIP
ISSUE TODAY WILL BE ON BRIDGES & ELEVATED AREAS IN ADVSY AREA.
MINOR ACCUMULATIONS AT THAT. OTHER LOCATIONS WILL STILL JUST
ABOVE FREEZING. 47

&&

.MARINE...
OFFSHORE WINDS STILL EXPECTED TO PICK UP TODAY AS STRONG CAA
CONTIN- UES. THE TIGHTENED GRADIENT WILL HELP TO KEEP ADVISORIES
(OR CAUTION FLAGS) UP THROUGH SAT AFTN AT THE VERY LEAST.
WINDS/SEAS EXPECTED TO SUBSIDE RAPIDLY BY SUN AS THE SFC HIGH
SETTLES OVER THE STATE. LIGHT AND VARIABLE WINDS BRIEFLY ON MON
AHEAD OF THE NEXT FRONT MOVING IN- TO THE COASTAL WATERS.
ADVISORIES/CAUTION FLAGS LIKELY AGAIN FOR MON NIGHT ON INTO TUES
NIGHT. 41

&&

.AVIATION...
GETTING REPORTS OF UNKNOWN PCPN AT CLL/UTS THIS MORNING...BUT
ASSUM- WE ARE DEALING WITH A WINTRY MIX (SLEET/FREEZING RAIN).
HAVE ADDED A TEMPO GROUP FOR THIS AT THESE LOCATIONS...AND MAY
HAVE TO ADD TO CXO BEFORE ALL IS SAID AND DONE THIS MORNING.
OTHERWISE KEEPING WITH THE IFR/LIFR CIGS THROUGH THE REST OF THE
MORNING...POSSIBLY "IMPROVING" TO MVFR LATE THIS AFTN AS THE PCPN
FINALLY MOVES OUT. 41

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 35 27 35 29 42 / 70 10 40 40 30
HOUSTON (IAH) 39 32 38 34 44 / 70 20 50 50 30
GALVESTON (GLS) 48 38 44 41 50 / 60 20 50 40 30

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR THE
FOLLOWING ZONES: BRAZOS...BURLESON...GRIMES...HOUSTON...
MADISON...WALKER...WASHINGTON.

GM...SMALL CRAFT ADVISORY UNTIL 9 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60
NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT
20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.

[Katdaddy]

A cold morning with patches of light rain across SE TX. Freezing drizzle/light rain threat continues mainly N and W of Houston later tonight through Sunday morning. Winter Weather Advisories and Winter Storm Warnings cover a large part of TX including Del Rio, San Antonio, Austin, and the Dallas-Ft Worth areas. The situation in Dallas-Ft Worth is getting very serious with 182,000 now without power and numerous reports of traffic accidents, transformers popping, and trees snapping.

[srainhoutx]

Morning Update From Jeff:

Damaging ice storm in progress over N TX this morning.

Potential for light ice accumulations over SE TX today into Saturday.

Winter Weather Advisory issued for: Brazos, Burleson, Grimes, Houston, Walker, Madison, and Washington Counties until 300pm today

N/NW/NE TX Ice Storm:

Crippling ice storm in progress overnight over this part of the state. Dallas has been reporting freezing rain and sleet for the last 12 hours with temperatures in the mid to upper 20’s. Abilene has reported freezing rain with a temperature of 19 which is just insane. Nearly everything that is falling over this area is freezing on contact forming a now thickening layer of ice and sleet. Widespread power outages are already in progress over this region with 150,000 outages reported and this is going to be going up quickly this morning as trees and power lines are at their breaking point. Travel even on surface roads has become nearly impossible in the warning areas with TXDOT crews unable to keep enough sand on the roadways to keep them open due to the heavy nature of the falling precip. Moderate to at times heavy freezing rain will continue for the next several hours over this part of the state with ice accumulations reaching between .50 -.75 of an inch possibly an inch in some areas which is going to be devastating to the above ground power system. Temperatures are forecast to drop dangerously low by Saturday morning over this part of the state (10-18F) and likely remain at or near freezing into early next week keeping ice and power issues ongoing for several days.

SE TX:

Temperatures have fallen only a few degrees since last evening over the area and range from 34-35 NW to 37-39 Houston to 39-43 along the coast. Light rain has develop over parts of the area this morning, but surface temperatures remain warm enough to keep it from freezing. The College Station sensor has been reporting freezing rain…but this is incorrect with an air temperature of 34. Temperatures may drop another degree or tow today across our NW counties as cold air advection across the ice coated N TX draws some colder air southward. Some very light ice on elevated surfaces would be possible in the mentioned advisory area…but think this is very marginal and most bridges/overpasses will be ok. Rain and drizzle is falling from a very warm layer about 3000-5000ft above the surface with temperatures in the 50’s so the liquid is actually fairly warm and 31-32 will likely not cause much freezing. As noted overnight the biggest problems have been where surface temperatures have dropped to the mid and upper 20’s.

Tonight-Saturday:

Better potential for the surface temperature to fall to or below freezing across the northern ½ of the area (roughly north of I-10) by Saturday morning. Not looking at much rainfall tonight, but moisture begins to increase on Saturday ahead of another disturbance aloft moving into from the SW. Given very warm conditions aloft and warm ground conditions with very marginal freezing surface temperatures (30-32) this still does not look to be any significant ice potential. With that said could see some minor ice accumulations on Saturday into Saturday evening over areas north of I-10 with a few icy spots on bridges and overpasses. Expect amounts to range from a trace to .05 of an inch, but it should be made very clear that even .01 of ice on a bridge is potentially dangerous and especially so when they appear dry and in fact have frozen over from freezing drizzle. Freezing drizzle is about the worse winter precipitation as people tend not to exercise caution on bridges as they appear dry but will have a very thin layer of very slick ice. Think a winter weather advisory will be issued later today and may include portions of Harris County and areas N and W for the potential for minor ice accumulation Saturday into Saturday night. Temperatures will fall into the mid 30’s tonight and hover between 30-34 all day Saturday.

Sunday-next week:

Cold arctic dome remains locked in place and a secondary surge arrives around Monday keeping the entire state very cold. Lows will continue to be at or below freezing through the period over portions of the area with highs not much above 40-45 each day. Jet stream remains active and shows potential for more bouts of precipitation early next week…again could be dealing with some mixture of P-types depending on cold air depth and surface temperatures.

Will update again this evening.