December 2017: End Of The Year Weather

[srainhoutx]

The GEFS/ECMWF EPS Ensembles are fairly consistent with a highly amplified pattern as Christmas arrives. While it is far too soon to know the "finer details" at this range of 2 weeks out, the indicators we look to in the longer range do raise an eyebrow. Christmas Week could be very chilly across much of the Lower 48 should this type of pattern verify. Those heights shown even in the Ensemble 2 weeks out suggest the strongest and likely coldest High Pressure domes we have seen so far this season over Alaska dropping through Western Canada into the Northern Rockies.

[tireman4]

000
FXUS64 KHGX 111128
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
528 AM CST Mon Dec 11 2017

.AVIATION...
VFR. Scattered cirrus with a weak westerly breeze. The dry
passage of a early Tuesday morning front will veer late period
winds around to moderate northwest. 31

&&

.PREV DISCUSSION... /ISSUED 414 AM CST Mon Dec 11 2017/

DISCUSSION...
Slightly warmer temperatures can be expected again today
under west to southwest surface winds. Look for increasing
high clouds to move across the area from the west. This
warmup will not last long as the next cold front moves
through the area tonight/early tomorrow. No rain is expected
with the front. Temperatures will remain on the cool side for
the remainder of the week, and a reinforcing front will move
through Thursday/Thursday night. Moisture levels rise a
little ahead of this front, but thinking has not changed
that best rain chances will remain off the coast. Look for a
warmup over the weekend ahead of the area`s next cold front.
We might be able to get some rain develop with this front as
moisture levels rise, so will continue to carry low rain
chances Saturday night and Sunday. It still looks like the
best rain chances with this system will be off to our east
and northeast, similar to what WPC has on their latest Day
6-7 QPF forecast. 42

&&

MARINE...
High pressure centered over southern Texas is producing weak
westerlies over low seas and this pattern will persist through the
day. The approach and passage of the next cold front tomorrow will
veer morning winds around to northwesterly and strengthen them to
SCEC levels around sunrise. Tuesday`s caution level winds will
weaken and veer northeasterly early Wednesday. Light and variable
winds through mid week will again turn (south)westerly Thursday with
an early Friday cold frontal passage again pushing northwesterlies
to caution (possibly Advisory) levels during the day Friday. Tuesday
and Friday`s cold frontal passages will lift sea heights to an
average 4 to 6 feet while generally being dry (very low to slight
rain chances). Deepening western Plains low pressure Saturday will
gradually strengthen weekend southerly winds. The models are
currently depicting the lifting of a southwestern storm system
across the waters next Sunday that...if this remains a consistent
scenario...will increase early week shower and storm chances. 31

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 73 42 61 36 64 / 0 0 0 0 0
Houston (IAH) 72 44 63 38 63 / 0 0 0 0 0
Galveston (GLS) 70 51 63 47 62 / 0 0 0 0 0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

Discussion...42
Aviation/Marine...31

[wxman57]

The American model (GFS) has been predicting another cold outbreak for around the 24th, possibly with sub-freezing air at the surface along with precipitation. However, the GFS shows well above freezing temps just above the surface, which would indicate sleet/freezing rain vs. snow.

Keep in mind that neither the GFS nor the Canadian model correctly predicted last week's snow event until just over 48 hours from the start of the snow. However, the GFS was predicting colder air aloft with the snow event than it is predicting for around Christmas. I wouldn't trust the GFS too much until maybe the Friday to Saturday before Christmas (Dec. 22-23). At the very least, there are strong indications that we'll see a cold front around Christmas.

[tireman4]

Did you see this stat?

[tireman4]

What Srain and Wxman 57 are alluding to in their forecasts..enjoy this while you can folks..

[tireman4]

000
FXUS64 KHGX 111604
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1004 AM CST Mon Dec 11 2017

.UPDATE...

Surface analysis this morning shows low pressure in the Plains
associated with a pretty strong short wave trough seen on water
vapor satellite imagery. We should have light west to southwest
winds today with mostly clear skies. Temperatures should reach the
low 70s this afternoon making for a very nice day across the
area.

Cold front associated with the low pressure in the Plains should
push through the area tonight into Tuesday morning with just a
wind shift. The colder airmass will allow for high temperatures
Tuesday in the low 60s.

Overall only changes to the forecast were for short term trends
in temperature, dewpoint and sky conditions which will mostly go
unnoticed since the forecast was on track to begin.

[MontgomeryCoWx]

The last 7 model runs have shown a cold front passing our region around Christmas Eve. Getting pretty consistent.

[tireman4]

Please use this with caution..nice to look at ...

[snowman65]

Please use this with caution..nice to look at ...

That's alot of "moisture" in the air...

[tireman4]

000
FXUS64 KHGX 111752
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1152 AM CST Mon Dec 11 2017



.AVIATION...
VFR. Westerly winds today may briefly back to the southwest ahead
of the cold front. Cold front with increasing northerly winds coming
through 06z CLL area and IAH/HOU 09-10Z and GLS by 11-12z.

[MontgomeryCoWx]

Well this is one way to get cold in our area. Have the EPO tank into the depths of the abyss.

[tireman4]

Humm..again..please take this with a grain of salt. Still way out and a lot of things can happen ( our pro mets Srain, Wxman 57 and Blake have all stated this...)..but...it is pretty to look at if you are a cold weather fan.

[srainhoutx]

I see that wxman57 has edited the December Topic Title to cover the Christmas potential. We'll leave this Topic open for several days and likely merge it into the December Topic to avoid any confusion and to keep a central Topic for historical purposes if things turn wintry for the second time in a month.

[snowman65]

The GFS wants to keep us at or below freezing from 12Z on the 25th through the 27th...hmmm

[harp]

Got quiet in here. Did the GFS back off on the cold, etc.?

[MontgomeryCoWx]

Got quiet in here. Did the GFS back off on the cold, etc.?

No, still there on 18z

[harp]

Got quiet in here. Did the GFS back off on the cold, etc.?

No, still there on 18z

Thanks. Precip as well?

[MontgomeryCoWx]

Southern plains storm still there too

[harp]

I follow this forum (especially in winter) because what ya'll get there, we get the next day here in SE Louisiana. Case in point is last week's snow. Does the GFS still have precip for the Gulf Coast for the Christmas front?

[MontgomeryCoWx]

It does but just liquid. With that said, these fronts are known for being modeled slower and warmer than the actual result.