Texas Fall-2016

[weatherdude1108]

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
258 PM CST Wed Nov 16 2016

.SHORT TERM (Tonight through Thursday Night)...
After a warm, sunny and gusty afternoon with some breaking daily
maximum temperatures, expect clouds to develop this evening into
the overnight hours. Increased low level moisture is forecast to
push across the coastal Plains and then into the I-35 corridor.
Areas along the coastal Plains could see areas of fog while
patchy fog is expected across most areas along and east of
Interstate 35. Low clouds are expected to scatter out by mid-
morning Thursday for partly cloudy skies across most of the
region. It will be a bit cooler due to cloud coverage and
therefore no anticipating breaking maximum daily records.

&&

.LONG TERM (Friday through Wednesday)...
An upper level system will be moving across the four corners
region into the Southern Plains late Thursday into Friday. This
system will be sending a strong cold front across South-Central
Texas on Friday for chances of showers and thunderstorms. There is
a slight chance for showers across the Hill Country around dawn as
a short-wave trough moves ahead of the frontal boundary. This is a
progressive and quick moving frontal boundary and should exit the
area by mid-afternoon on Friday. Rainfall accumulations could
range from few hundredths to one quarter inch with few spots
getting up to three quarter of an inch. Breezy northerly winds and
gusts up to 20 mph are expected in the wake of the cold front
through the evening hours.

The upcoming weekend will be cooler than climate normals as the
cool airmass spreads across the area. Saturday`s high temps will
only get into the upper 50s across the Hill Country to mid 60s
along the coastal Plains. Sunday morning lows will significantly
drop as a result of clear skies and light winds. This will be the
coldest airmass so far this fall to enter the area with expected
low temperatures to reach the lower 30s across part of the Hill
Country. Some areas across the Hill Country could experience
temperatures in the 30-32 range for few hours. Sunday`s highs will
increase several degrees from those expected on Saturday as
southerly winds return.

A warming trend is expected for the beginning of next week with
a slight chance for rain expected late Tuesday into Wednesday as
another upper level disturbance pushes through the area. Models
are keeping the second part of next week dry.

[Ntxw]

87F today which is a daily record for dfw. Tomorrow's record is 87F from 2013, and the all time Nov high is 89F from 1989 and 2005

[Brent]

This weather is disgusting. I thought we were done with heat

[weatherdude1108]

We don't even need a Fall thread this year. We can just move straight to the Winter thread.

[gpsnowman]

Had to turn on the a/c today just to mix up the air. Unbelievable. Man I hope winter comes in with a serious bang and stays that way for a looooonnnnnggggg time. It sure doesn't feel Thanksgiving is a week out. This is terrible.

[starsfan65]

This weather is disgusting. I thought we were done with heat

I'm so done with this warm weather.

[Portastorm]

Enjoy this beautiful weather while it lasts. Changes are lurking just beyond Thanksgiving and I will not be surprised to see the zonal flow relax and the 'stepping down' process begin in earnest as we near Mid December. By the Christmas Holiday period, we could be wishing for warmer weather. In a couple of weeks we will see if that 1983 analog has validity...

Srainhoutx, to achieve 1983, we will have to get an incredible shift in the Pacific pattern imo. Way too progressive. Even with a -ao and -nao, the Pacific is still too strong. Imo obviously . Hopefully it changes though

1983 behaved like this with the Pacific, it managed to relax in December. Though we are warmer at the surface than 1983 at the surface. Also 1983 was a volcanic winter post El Chichon but that doesn't mean the 500mb progression can't follow it

So, you're saying then that we just need to root for a big volcanic eruption somewhere soon?!

[weatherdude1108]

Srainhoutx, to achieve 1983, we will have to get an incredible shift in the Pacific pattern imo. Way too progressive. Even with a -ao and -nao, the Pacific is still too strong. Imo obviously . Hopefully it changes though

1983 behaved like this with the Pacific, it managed to relax in December. Though we are warmer at the surface than 1983 at the surface. Also 1983 was a volcanic winter post El Chichon but that doesn't mean the 500mb progression can't follow it

So, you're saying then that we just need to root for a big volcanic eruption somewhere soon?!

[Ntxw]

So, you're saying then that we just need to root for a big volcanic eruption somewhere soon?!

Given how warm it has been the past 24 months, at this rate we may need an eruption from Toba . You know its bad when Austin can't even get frzng drzle

[Golf7070]

So, you're saying then that we just need to root for a big volcanic eruption somewhere soon?!

Given how warm it has been the past 24 months, at this rate we may need an eruption from Toba . You know its bad when Austin can't even get frzng drzle

Ntxw, on a serious note, when do u think we will see a full pattern change? Do we still have a ways to go? You would think the proverbial shoe will drop sooner or later

[TeamPlayersBlue]

Alot of long range models saying a flip is coming. Not entirely sure if thats good or bad yet!

[Ntxw]

Ntxw, on a serious note, when do u think we will see a full pattern change? Do we still have a ways to go? You would think the proverbial shoe will drop sooner or later

Depends on what you mean by pattern change. All guidance points to Aleutian ridge disturbing the Pacific and for the past week has shown Hudson Bay blocking with the jet undercutting below. That's a winter storm pattern. What's unsure is if there is any true cold air, Canada for the time being is still warm. There is no severe -EPO block to send down an arctic blast, the instant switch, that we like to feel when we hear pattern change in the near future if that is what you're asking.

[Golf7070]

Ntxw, on a serious note, when do u think we will see a full pattern change? Do we still have a ways to go? You would think the proverbial shoe will drop sooner or later

Depends on what you mean by pattern change. All guidance points to Aleutian ridge disturbing the Pacific and for the past week has shown Hudson Bay blocking with the jet undercutting below. That's a winter storm pattern. What's unsure is if there is any true cold air, Canada for the time being is still warm. There is no severe -EPO block to send down an arctic blast, the instant switch, that we like to feel when we hear pattern change in the near future if that is what you're asking.

I've just been hearing a lot about the PV splitting and getting displaced, a developing SSW. Ntxw, you would think the Pacific jet would retract sooner or later but hasn't happened yet. Stronger than normal. I guess what I'm getting at is when we can get some of those decent Arctic highs coming down and the pattern not be so transient. It's difficult to get snow/ ice opportunities in that setup. A SSW don't do us any good if all the cold air heads overseas

[TheProfessor]

We're going to go from 71 degrees on Friday to possible snow showers Saturday afternoon/night. I'm actually not that excited for it, that first big drop is always the worst one.

[Ntxw]

Euro OP isn't bullish yet but it's ensembles are along with the GFS and GEFS of storms. Likely ones that we look at run after run to see where they track and wintry weather complications. Could be an interesting ride past the next 7 days. Hudson block doing some work.

If you are wondering what I'm talking about here is 3 (arguably) for DFW's snowiest periods that we all love







What a Pacific jet 1977-1978 had! Slogan...you block it, you lock it, you rock it . Optimistic post for the day


On a side note the ECMWF (euro) will be getting a fairly substantial upgrade next week

[Ralph's Weather]

Euro OP isn't bullish yet but it's ensembles are along with the GFS and GEFS of storms. Likely ones that we look at run after run to see where they track and wintry weather complications. Could be an interesting ride past the next 7 days. Hudson block doing some work.
If you are wondering what I'm talking about here is 3 (arguably) for DFW's snowiest periods that we all love
What a Pacific jet 1977-1978 had! Slogan...you block it, you lock it, you rock it . Optimistic post for the day
On a side note the ECMWF (euro) will be getting a fairly substantial upgrade next week

Everything is sure looking good to start off December.

[Ntxw]

Ntxw, on a serious note, when do u think we will see a full pattern change? Do we still have a ways to go? You would think the proverbial shoe will drop sooner or later

Depends on what you mean by pattern change. All guidance points to Aleutian ridge disturbing the Pacific and for the past week has shown Hudson Bay blocking with the jet undercutting below. That's a winter storm pattern. What's unsure is if there is any true cold air, Canada for the time being is still warm. There is no severe -EPO block to send down an arctic blast, the instant switch, that we like to feel when we hear pattern change in the near future if that is what you're asking.

I've just been hearing a lot about the PV splitting and getting displaced, a developing SSW. Ntxw, you would think the Pacific jet would retract sooner or later but hasn't happened yet. Stronger than normal. I guess what I'm getting at is when we can get some of those decent Arctic highs coming down and the pattern not be so transient. It's difficult to get snow/ ice opportunities in that setup. A SSW don't do us any good if all the cold air heads overseas

The blocking so far has been more aimed towards asia and europe. High pressures have been over Scandinavia, Barents, and Kara Seas. There are good signs next bout of blocking could benefit the WHEM being between Hudson Bay and Greenland.

Still even if we don't see the EPO blasts, doesn't mean we can't get what srain likes to say..step down

[Texas Snowman]

Post of the year so far!

"You block it, you lock it, you rock it." -- Ntxw

[Tireman4]

000
FXUS64 KHGX 171338
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
738 AM CST Thu Nov 17 2016

.UPDATE...
Another change to the dense fog advisory, as observations at
Brenham are at one quarter mile visibility. Webcams from the area
are essentially a whiteout, so expansion of the advisory to
Washington County is necessary. With conditions slowly improving
to the south, will continue to hold to 9am as the end time for the
time being.

&&

.PREV DISCUSSION... /ISSUED 545 AM CST Thu Nov 17 2016/

UPDATE...
Visibilities have trended sharply upwards near the coast, and so
have let the bottom two tiers of counties go from the dense fog
advisory. 11-3.9 um imagery and the HRRR suggest some northward
drift in the dense fog, and will be keeping a watchful eye on
Washington and Burleson counties for potential expansion before
expiry. Dense fog is also being reported at the very fringes of
Harris and Liberty counties, but is probably not widespread enough
to justify addition at this time. In the Houston metro
particularly, webcams have been helpful in pinpointing the limited
extent of the dense fog. Still, will also be keeping a close eye
on obs and cams in those areas to ensure conditions do not degrade
in the next few hours before fog dissipates.

AVIATION...
Low cloud and fog areas are spotty early this morning, but general
trend on area obs is for improving conditions. Any MVFR/IFR
locations will improve after sunrise as south winds begin to
increase, then mostly VFR into the afternoon and early evening hours
with south winds generally running 8 to 12 knots. Weakening winds
tonight and increasing moisture could allow for another round of low
clouds and fog, but not confident enough at this time to include in
the TAFs. Think tomorrow`s SHRA/TSRA and associated wind shift to
the NNW and N with the strong cold front will hold off until
around/after 18/15z north (CLL and UTS) and 18/18Z at remain sites
to the south. 42

PREV DISCUSSION... /ISSUED 344 AM CST Thu Nov 17 2016/

DISCUSSION...
Immediate forecast issue is on dense fog developing in the area.
Many locations in the advisory area are reporting one quarter mile
or worse visibility. Some locally dense fog may be creeping into
Liberty County, but obs and webcams show Harris County remains
free and clear. For now, will leave the advisory area unchanged,
but will have a hair trigger on Harris and Liberty.

After this morning, focus turns to the big story of the forecast
period - the frontal passage set to occur Friday. This will bring
both rain along the front, to be followed by breezy conditions
Saturday morning and a cooler, drier airmass for the weekend.

Rest of tonight through Thursday...
Light winds and clear skies have allowed fog to develop across
the area, and necessitated a dense fog advisory - mainly
west/southwest of the Houston metro. As discussed above,
conditions will be monitored closely in case any expansion is
needed. The fog should dissipate in the mid- morning, and from
there, one last nice - if unseasonably warm - day is ahead. There
are indications in multiple models that a pre-frontal trough will
move into SE Texas, and have introduced some very low PoPs,
generally similar to the TTU WRF, for the nighttime hours.

Friday through Saturday morning...
The cold front should move in from the northwest towards mid-day,
and by evening looks to reach the coast. Some concern that a
scenario in which a pre-frontal trough comes in early that
convergence will be decreased for convection with the main front.
However, there`s enough moisture and this seems a stout enough
front to have the confidence for some likely PoPs through the
center of the area this afternoon. Would expect to see some
lightning, as most guidance manages to build 1000 j/kg of MLCAPE
(or more). Deep layer shear is not so impressive, and while
hodographs show a generally favorable shape, the details are a bit
of a mess. As a result, severe weather is not really anticipated.

Behind the front, expect northwest winds to pick up with a surge
of colder, drier air. Not only does a small craft advisory seem
likely, but an occasional gust to around gale force may occur (for
more on this, see marine section below). Along with that, a wind
advisory for the immediate coast might be needed as well. Inland,
winds do not look to be quite so big a concern. However, low
temperatures Friday night into Saturday morning in our north and
northwest look to fall into the lower 40s as the colder air shoves
in.

Saturday afternoon and beyond...
Clouds should clear out quickly, with fair skies for the weekend.
The cold airmass takes hold, with highs in the lower to middle 60s
on Saturday, bumping up into the middle to upper 60s Sunday. With
high pressure/ridging in place throughout the column and very dry
air in place Saturday night, we could see some very chilly temps
overnight. Nobody should drop below freezing, but cold spots may
drop into the middle 30s. Onshore flow at the surface looks to
return Sunday night, and rising dewpoints should keep temperatures
from crashing quite as far Sunday night. Still, would expect
another night of below normal lows.

While the upper ridge moves eastward overhead into the early week
and with onshore flow, there should be gradual warming to near or
even above normal temperatures for the first part of the week.
However, the pattern is pretty progressive, and by midweek, we
should be looking for another frontal passage. Tough to parse out
details for now, as the Euro continues to bring in a stronger (but
filling/lifting) trough, while the GFS has the ridge hold a bit
tighter, glancing a weaker trough up to the Great Lakes. Given
that neither the deterministic nor ensemble guidance suggest it,
there is a fair amount of confidence that the impacts of this
front will not match those of the earlier front.

Luchs

MARINE...
Onshore winds are strengthening (already 16 knots at Buoy
42019), so have gone ahead and hoisted caution flags for
our 20-60 nm waters. Wind speeds should hover in a 15-20
knot range through early Friday morning. At that time,
winds should come down a little ahead of a strong cold
front that will move off the coast late Friday afternoon
or early Friday evening. Strong north winds (with gusts
possibly reaching gale force) and rough seas can be expected
Friday night through Saturday morning behind the front as
strong high pressure builds into the area. Conditions
should improve Saturday night and on into Sunday. Onshore
winds return on Sunday night and Monday as the high moves
off to the east. Another cold front (not as strong as the
one this weekend) is expected around mid week. 42

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 80 65 73 44 62 / 0 10 50 0 0
Houston (IAH) 82 68 80 47 64 / 0 10 70 20 0
Galveston (GLS) 79 72 80 54 63 / 0 10 50 40 0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Dense Fog Advisory until 9 AM CST this morning for the following
zones: Austin...Colorado...Montgomery...Waller...Washington.

GM...SMALL CRAFT SHOULD EXERCISE CAUTION through late tonight for the
following zones: Waters from Freeport to the Matagorda Ship
Channel from 20 to 60 NM...Waters from High Island to
Freeport from 20 to 60 NM.

&&

$$

Discussion...25

[Brent]

FWD now has a freeze here Sunday Morning, and upper 20s just outside the metro.

Also the warmest high is 70 next Tuesday.