JANUARY 2018 - Seasonal WX Week/Pacific Front Saturday

[MontgomeryCoWx]

I know we haven't been real cold (yet), but outside of the 2013/2014 Winter I can't recall an extended stretch of below normal temps like we have (and will) seen starting from last Friday and potentially running through the second full week of January.

Maybe my memory is failing me, but I have to go back to December 2000, I think, to find a multi week stretch like this. In December 2000, I was in College Station, so I'm not positive that Houston isn't further back than that.

[WWxHopeful]

I know we haven't been real cold (yet), but outside of the 2013/2014 Winter I can't recall an extended stretch of below normal temps like we have (and will) seen starting from last Friday and potentially running through the second full week of January.

Maybe my memory is failing me, but I have to go back to December 2000, I think, to find a multi week stretch like this. In December 2000, I was in College Station, so I'm not positive that Houston isn't further back than that.

You'd be correct. Winter 2000-2001 seemed it was at or below normal all the way through the beginning of February. 2009-2010 also had many days below normal

[srainhoutx]

Thursday morning briefing from Jeff:

Strong arctic cold front to arrive on NYE…very cold start to 2018.

A cold arctic air mass developing over NW Canada will become dislodged over the next 24 hours and surge into the US. This strong front will arrive into TX on Sunday and blast off the TX coast Sunday evening. A very cold air mass will pour into the state from the NNE with the freezing line moving southward into SE TX Sunday evening. Areas north of I-10 will likely fall below freezing early Monday (NYD) morning and only warm into the mid 30’s on NYD. Appears even colder conditions will be likely on Monday night/Tuesday morning with the freezing line progressing all the way to the coast and possibly a hard freeze (25 degrees or lower) for areas along and N of US 59. Wind chills on NYD (Monday) may fall well into the 10’s over portions of the area and should those values fall below 13 over a widespread area a wind chill advisory would be required.

Precipitation:

Sunday Evening (NYE)/Monday Morning (NYD):

Post frontal air mass will initially be shallow in nature…maybe a few thousand feet thick…and moisture will run up and over the surface cold pool. This may result in a period of drizzle or light rain showers Sunday evening into early Monday morning. Surface temperatures will be falling to and below freezing by late evening north of a line from Columbus to Livingston and any light rain or drizzle could change to freezing drizzle. Accumulations are expected to be very light…less than a few .01’s of an inch if anything. Drier air moving into the region may negate any precipitation at all once the temperatures fall below freezing. Could see freezing of any puddles of water left by rains during the day on Sunday Monday morning as the surface temperatures fall into the 20’s N of I-10. Overall chance of any freezing precipitation N of the Columbus to Livingston line is around 10-20%.

Tuesday/Wednesday:

Very cold arctic high pressure will be in full control of much of the nation including SE TX with very cold conditions across SE TX. The ECMWF and CMC models bring another short wave through the mean trough and across SE TX on Tuesday into Wednesday while the GFS shows a much weaker piece of energy. Both the ECMWF and CMC generate precipitation across a very cold SE TX air mass during this period while the GFS is completely dry.

Since this is still several days out and model agreement is poor at this time…hard to determine what if any precipitation will fall over the area and what sort of impacts may result. Something to keep an eye on in the coming days.

Key Messages:

1) Very cold air will arrive in SE TX NYE with hard freeze possible N of US 59 by morning of ½
2) Cold weather protection of the “4 P’s” will be needed late NYE through much of next week. It will be cold enough to be concerned about any exposed outdoor pipes and sprinkler systems.
3) Light freezing drizzle/rain will be possible for a short period of time NYE evening/early NYD north of a Columbus to Livingston line with little to no ice accumulation currently expected
4) Residual water puddles from Sunday rainfall will likely freeze NYD morning north of I-10 which could result in a few slick spots
5) Precipitation is possible Tuesday/Wednesday, but the forecast is highly uncertain on how much, where, and what type.

[Andrew]

12GFS continues the warmer trend. Looks like between the GFS and ECMWF they have flipped. GFS is known though for underestimating these type of cold air events, especially in this time frame. It often shifts the cold air east too fast too. It is interesting to see the stark difference precip wise between the two models, especially when dealing with the shortwave ejection.

[redneckweather]

So wxman isn't shooting down the possibilities of wintry precip down here next week. Hmmmmmm

[Ptarmigan]

I know we haven't been real cold (yet), but outside of the 2013/2014 Winter I can't recall an extended stretch of below normal temps like we have (and will) seen starting from last Friday and potentially running through the second full week of January.

Maybe my memory is failing me, but I have to go back to December 2000, I think, to find a multi week stretch like this. In December 2000, I was in College Station, so I'm not positive that Houston isn't further back than that.

Winter of 2000-2001 was cold. December 2000 is one of the coldest December on record. It is the coldest outside of December 1983 and 1989!

http://www.weather.gov/hgx/climate_iah_top10_dec

Another cold winter is 2009-2010, which is one of the coldest winters on record.

[Ptarmigan]

When Houston Saw Highs That Were In The 20s
January 1, 1928
January 10, 1962
January 12, 1892
January 18, 1930
January 19, 1940
January 20, 1978
January 22, 1930
January 30, 1949
January 30, 1951
January 31, 1951
February 1, 1951
February 2, 1951
February 1, 1985
February 4, 1989
February 7, 1895
February 8, 1933
February 9, 1929
February 13, 1899
February 14, 1895
December 20, 1924
December 23, 1989
December 24, 1983
December 25, 1983

This is from 1889 to 2017. I suspect there that the highs did not go above 20s in the 1820-1821, 1845-1846, 1852, 1873, 1875, January 1886, and January 1888 Freeze. The high in Galveston on January 8, 1886 was 31°F and on January 16, 1888 was 32°F.

It is a rare occurrence. 23 have occurred in Houston from 1889 to 2017. On average that should be every 5.6 years. The last happening on December 23, 1989.

The lowest high was on February 13, 1899, with a high of 20°F! The latest date to see 20s as a high was on February 14, 1895, which was during the epic snow event.

Got It From Here
http://threadex.rcc-acis.org

[TexasMetBlake]

Hmm the 12z GFS continues to warm and shunts almost all the true Arctic air east.

This is where it gets fun. Who blinks first? The very cold, snowy Euro or the "warm", dry GFS?

[mcheer23]

Can't wait to see the ECMWF run in about 10 min.

[ticka1]

now is the time to check on people pets plants and pipes! if you have elderly neighbors/family or friends please check on them make sure they have food and heat.

[TexasMetBlake]

12z Euro is warmer and bone dry now -- very much like the GFS.

[mcheer23]

12z Euro is warmer and bone dry now -- very much like the GFS.

Going to be some interesting 00z runs tonight...

[MontgomeryCoWx]

Still don't get above freezing from late afternoon NYD through late morning Wednesday it looks like. Stays cold through the end of next week.

Highs in the low to mid 30s NYD in my general area. I'll take it, just with precip!

[Cromagnum]

I'm sure we will have to wait until Sunday before we know what's going to happen early next week, but this twenty degree delta of temperature centered around 34-35 degrees doesn't give me a lot of confidence. This is either a lot of work this weekend to prepare, or ignore it completely and got about my day

[DoctorMu]

Climate pages are back on NOAA:

http://www.weather.gov/hgx/climate_graphs

Generally pretty cool from CLL to Galveston since Dec. 5th and more chill to come.

[srainhoutx]

I was reading back a week before the December 7th- 8th snow event and it wasn't until Tuesday when the shorter range Mesoscale Models where within 48 hours of that event starting that we had somewhat of a clue that there was a chance of a wintry mix and at 48 hours those shorter term models where guessing mostly a Coastal Counties event versus what really happened. Keep that in the back of your mind when attempting to analyze what may occur Monday into Tuesday.

The afternoon Updated Surface Charts for Monday and Tuesday hint at a wave of low pressure in the NW Gulf with a Coastal trough. Also it is not often we see the Weather Prediction Center indicate a 1056 Artic high over Nebraska New Year's Day. I certainly believe it's going to be much colder than the early December snow event. As far as an precipitation falling through that cold air, that's the $64,000 question.

[jasons2k]

This cold weather is getting old. Cabin fever is setting in. I’m ready for some nice, mild weather again so I can enjoy the outdoors. In the meantime, I think I’ll go make lasagna.

[Andrew]

Interesting to note on the GFS how it shows a relatively saturated column Tuesday morning as the shortwave rotates south. It is pretty close to showing precipitation with that profile. Of course more moisture would help but it may be trending towards a slightly wetter solution. This is also the reason it only has temps getting down to around freezing compared to the 20s.

[mcheer23]

I see the KHOU forecast has temps struggling to get out of the 20s Tuesday.....

[MontgomeryCoWx]

I see the KHOU forecast has temps struggling to get out of the 20s Tuesday.....

Probably accurate given the strength of the High coming down and how cold the source region is right now.