December 2016- End Of Year Forecast

[jasons2k]

I've had 1.31" so far. Keeping an eye on the radar for overnight trends.

[Andrew]

Trough axis remains offshore which is preventing a lot of convection from streaming/maintaining itself onshore. Still think tomorrow night into Monday morning will be the best shot for heavier rain north of the coast.

[Andrew]

Starting to see a band form to the southwest, especially over Corpus.

http://weather.cod.edu/satrad/nexrad/in ... X-N0Q-1-24

[unome]

Area Forecast Discussion
National Weather Service Houston/Galveston TX
528 AM CST Sun Dec 4 2016

.DISCUSSION...
Frontal boundary and outflow stalled off the coast about 80 miles
with SW flow aloft pulling moisture across the boundary and
lifting across the coastal waters and SETX. Water vapor clearly
showing the tap of mid/upper level Pacific moisture combining with
the low level moisture off the Gulf. This is producing widespread
showers and thunderstorm over the Gulf waters and a second band
from Deep South Texas through the Corpus area and into the Wharton
area (probably close to the 925mb front). As a speed max in the
flow aloft rides up into the Coastal Bend expect that deep
convection should blossom from the Coastal Bend and over
Upper Texas coastal waters spreading into SETX with storms
weakening and becoming more stratiform in nature over the northern
half of the CWA. Heavy rainfall should mainly be confined to
areas along and south of the I-10 corridor today. Have pared back
the Flash Flood watch to align with this thinking. After the
record setting rainfall along the coast (7.68" at Galveston
Scholes Field) and amounts of 10-12 inches in Texas City obviously
any additional heavy rains will rapidly runoff becoming flooding.
Over the course of the day expect to see rainfall of 1-2 inches
mainly south with some isolated amounts of 3 to 5 inches. The
greater amounts should probably be focused closer to the coast.
May even get a report or two of pea hail in stronger storms. A
break in the precip inland will probably take place late this
afternoon or early this evening before the next big shot of rain.
Early Monday-Monday afternoon the upper low will be coming out
across SETX and should bring a large swath of showers and
thunderstorms wrapping around across the northern CWA. Impressive
jet aloft with a glancing blow of the LLJ should drag back in PW
of 1.5-1.85" across much of the southern CWA. Cool surface
temperatures and cloud cover should limit the instability and
hence limit severe threat but enough remains for thunderstorms to
fire off inland...over the Gulf stronger storms and possibly some
severe will be possible. Breezy conditions possible south of the
I-10 corridor and along and east of the I-45 corridor as surface
low tracks through the nearshore waters (possibly coming ashore in
Chambers county). Pacific cold front sweeps out the moisture and
by Monday evening precip should depart. Winds go from westerly
Monday night to east/southeast Wednesday morning. Much colder
airmass plunges down the Front Range Wednesday and should swing
through SETX Wednesday night. This should wring out the last of
the moisture possibly bring scattered showers to the area and
Thursday strong CAA dominates with drying and clearing of the low
levels though aloft Pacific moisture should continue and lead to a
belt of high clouds over the region. Tail end of the shear axis
comes through Friday morning and clouds should be diminishing.
This will make temperature forecasts very iffy...what should be
the coldest day of the season with freezing temperatures down to
around a Columbus-Conroe-Cleveland line problematic. If the clouds
are thicker and hang on then freeze line may be further north...if
the clouds clear earlier then the freeze line will be further
south. With some confidence the northern counties (Burleson-
Trinity) should see the first freeze. The cold airmass races on
eastward Friday and by Saturday afternoon return flow underway
with a warm up and increased rain chances. 45

&&

.MARINE...
Unsettled weather continues across the marine areas early this
morning. Periods of showers and thunderstorms are expected to sweep
across the coastal waters from the west through Monday as a compact
upper level system lifts into Texas from near the tip of Baja
California. Expect most showers and storms today to be capable of
heavy rainfall limiting visibilities to 1 NM or less at times.
However, there will be an increasing potential for strong to severe
thunderstorms tonight into early Monday morning as a frontal
boundary over the north central Gulf retreats westward in response
to a surface low lifting up the Texas coast and cannot rule out a
few strong wind gusts or an isolated waterspout as this happens.

Additionally, a strengthening surface pressure gradient as this low
lifts up the coast will result in east to southeast winds increasing
to near 20 knots and Small Craft Advisories are in effect for the 0-
60 NM waters this afternoon and tonight. Expect winds and waves to
remain elevated overnight, but decrease by Monday afternoon as the
surface low clears the western Gulf.

Tide levels this morning are running about 2-2.5 feet above MLLW and
have cancelled the Coastal Flood Advisory early as levels have
fallen below those producing impacts along the coast. Will need to
keep an eye on tide levels for the overnight period as easterly
winds ahead of the surface low may again result in tide levels
approaching 3 feet above MLLW, and minor wave run-up on coastal
highways will be possible.

Otherwise, dry conditions are expected to return to the marine areas
by mid-week as the early week system exits the area. A strong cold
front looks to move across the waters late Wednesday, and Small
Craft Advisories to possibly Gale Warnings may be needed behind the
front.

Huffman

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 55 49 58 45 69 / 100 80 80 10 10
Houston (IAH) 57 52 60 49 70 / 60 100 100 10 0
Galveston (GLS) 62 59 66 58 68 / 90 100 100 10 0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Flash Flood Watch through this evening for the following zones:
Austin...Brazoria...Chambers...Colorado...Fort Bend...
Galveston...Harris...Jackson...Liberty...Matagorda...
Waller...Wharton.

GM...SMALL CRAFT SHOULD EXERCISE CAUTION from 4 PM CST this afternoon
through late tonight for the following zones: Galveston
Bay...Matagorda Bay.

Small Craft Advisory from 4 PM this afternoon to 4 AM CST Monday
for the following zones: Coastal waters from Freeport to
the Matagorda Ship Channel out 20 NM...Coastal waters from
High Island to Freeport out 20 NM...Waters from Freeport to
the Matagorda Ship Channel from 20 to 60 NM...Waters from
High Island to Freeport from 20 to 60 NM.

SMALL CRAFT SHOULD EXERCISE CAUTION until 4 PM CST this
afternoon for the following zones: Coastal waters from
Freeport to the Matagorda Ship Channel out 20 NM...Coastal
waters from High Island to Freeport out 20 NM...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...45
Aviation/Marine...14

[srainhoutx]

The overnight longer range ensemble guidance appears to be coming into somewhat better agreement. Those hoping for colder weather, it looks like a decent chance that your wish will come true at least through mid month.

[redneckweather]

Looks like some decent cold coming but nothing out of the ordinary this time of year. Even if precip came into the picture it doesn't even look cold enough for any wintry precip, at least for us down here in Southeast, Texas. At least it won't be blow torched leading up to Christmas.

[srainhoutx]

Sunday morning briefing from Jeff:

Widespread rainfall continues over the region…some heavy

Impressive cold season rainfall event over the last 36 hours and another 24 hours of light to moderate rainfall with some heavier cells to continue. Impressive rainfall amount of 12.36 inches recorded at Texas City yesterday which resulted in significant flooding.

Coastal trough has drifted southward overnight shifting that axis of coastal heavy rainfall offshore. Main upper level system currently over NC MX is starting to eject toward TX and this will maintain lift over the top of the offshore coastal trough and widespread rainfall will continue today into tonight. Think the heaviest rainfall will be along the coast and offshore closet to the coastal trough. Additional totals of 1-3 inches with isolated amounts of 4-5 inches will be possible over the region. Bad news is that these higher totals will likely be over the areas that have already been hard hit and storm totals over SE Galveston County could approach 15 inches.

Upper level system moves over the area tomorrow with one last round of rainfall before dry conditions onset by Tuesday. Temperatures will also warm under clearing skies from the 50’s today to near 70 by Tuesday.

End of Week:
Main story post rainfall event will be the arrival of a modified arctic air mass into TX late Wednesday into early Thursday. Upper air pattern will become favorable for the delivery of a NW Canada air mass southward down the plains and into TX by mid week. Highs on Wednesday in the upper 60’s will be replaced with highs on Thursday in the 40’s with strong NW winds. Expect the front to arrive late Wednesday into Thursday morning and temperatures may fall much of the day on Thursday. Expect strong high pressure cell to bring gale force winds across the coastal waters and this will drive tides to well below normal by late Thursday. Models showing a fairly dry and cold air mass which could produce a widespread freeze by Friday morning…still early to try and determine how cold and how far south freezing temperatures will occur, but something to watch closely this week.



Rainfall Totals:

Texas City Moses Gate: 12.39
1.5 E Texas City: 11.82
Bayou Vista: 11.42
Galveston Causeway: 8.60
Highland Bayou: 8.12
Jamaica Beach: 7.96
Galveston: 7.47
Port Bolivar: 7.08
La Marque: 6.93
Freeport: 5.31
Danbury: 5.04
Brazos River at Freeport: 5.04
8 SSW Stowell: 7.01
Santa Fe: 5.36
San Leon: 3.88
Pinehurst: 3.90
Willis: 3.28
Huntsville: 5.98
Navasota: 3.01
Hempstead: 2.64
Prairie View: 2.58
Wharton: 2.83
East Bernard: 2.37

Clear Creek at Kemah: 5.36
Clear Creek at I-45: 5.16
Taylor Lake at Nasa Rd 1: 4.96
Spring Creek at SH 249: 4.00
Little Cypress Creek at Becker: 3.72
Cypress Creek at Katy Hockley: 3.64
Spring Creek at Hegar Rd: 3.72

[srainhoutx]

The 12Z GFS continues to trend slightly colder with the freeze line almost to the Coast. The GFS also suggests the high clouds the HGX mentioned this morning may be far enough offshore to allow for ideal radiational cooling Thursday night into early Friday morning.

[djmike]

Light rain all day in beaumont. Nothing compared to yesterday's waterfall. Over 6" yesterday in Beaumont. Today? A measly .30" so far. Ill take it though. 8"+ close to bridge city area.

[DoctorMu]

We've stayed north of most of the deluge.

2.6 in IMBY so far,

[Katdaddy]

Thankfully mostly light to some occasionally moderate rains have streamed across SE TX this afternoon after yesterday's coastal deluge. Only 3.86" at the house with 5.94" just 4 miles S and then the totals really ramp up toward Galveston Island.
Flash Flood Watch extended until noon Monday but scaled back to Brazoria, Galveston, Harris, Liberty and Chambers Counties where grounds are saturated and an additional 2" totals could lead to some ponding. The radar is fairly quiet across SE TX but the STX radar is showing development ongoing which will spread across the Upper TX Coast through the night.
The big weather story next week will be the cold air spilling across the Plains from Canada to the GOM. Still many days out but a freeze down to Houston metro is being advertised by models with the potential for a light freeze to the immediate coastal areas late next week.

[unome]

for Cypress, TX, Accuweather (currently) has our low hitting 28 Thur night http://www.accuweather.com/en/us/cypres ... r/33748_pc

NWS HGX has us in the low 30s Thur & Fri night (as of now) http://www.srh.noaa.gov/NWSwidget/index ... 6155814603

just a few degrees apart... I realize both forecasts may change before then, but either way, it would be wise to protect susceptible plants, etc... there's a lot of time before then to prepare for what might or might not occur & it is winter, so we should all be able to adapt to a freeze that isn't out of the norm for this time of year

nothing seems like pipe-buster weather, so far

[srainhoutx]

Ryan Maue
GFS 00z ruined my color bar w/850T more than 30°C below normal.
7-10 day forecast could be historically cold -- or just cold.

[srainhoutx]

The longer range GEFS ensemble guidance continues to advertise well below normal temperatures may be possible beyond mid December. The Hemispheric Pattern driving all the continuing reloading of our source Region with very cold Arctic air is a very negative -WPO and negative -EPO with a tanking AO regime. Also following the contours of an anomalous Arctic Bering Sea/Eastern Alaska Ridge suggests a strong cross Polar flow continues into the 20th or so of December, if the longer range ensemble guidance is correct.

[unome]

Area Forecast Discussion
National Weather Service Houston/Galveston TX
451 AM CST Mon Dec 5 2016

.DISCUSSION...
Short term concerns... Frontal boundary well offshore and at 4 am it looks like one of the surface lows is tucked in just east of buoy 42019... coincidently where a thunderstorm complex is spinning away... storms in the Gulf this morning have been looking like they were loaded with small hail favoring the left movers. Storms that move inland have been clipping along at 50-60mph so though they bring heavy downpours they are very short-lived. Across most of the central and northern CWA abundant stratiform rain with embedded showers blankets the area.

Flash flood watch will remain in effect until noon for the Brazoria/Harris/Galveston/Chamber/Liberty county area where last two days of rainfall has gotten the soil a good deal wetter. With the fast movement of the stronger cells rainfall rates thoughintense are only putting down 0.25-0.50" in hour. Expecting the frequency of the stronger storms to diminish but storm mode to become more one of stratiform with embedded showers/isolated thunderstorms this morning. Overall rainfall today expect widespread 0.25-0.75" with isolated totals near 2 inches. The stronger storms will likely focus closer to the warm front in the Gulf As the upper low just south of Big Bend this morning swings out to the east it should overhead of the College Station area around 01z and accelerate away into LA by 06z Tue. As the low comes east today the rainfall should taper off this afternoon from southwest to northeast and by early evening the rainfall should be over in Polk/Trinity counties if not sooner. Wrap around moisture will keep cloudy skies in place through this afternoon with clearing again from the southwest to northeast overnight. Weak high pressure over the area tonight and Tuesday will retreat Wednesday as polar jet dips down over KS/OK and Canadian/Arctic cold front pushes down across the state moving through SETX between midnight and 8 am Thursday. A chance of showers and rain across SETX ahead of the cold front with rain chances falling quickly Thursday with the cold air (strong CAA) making for near steady/falling temperatures Thursday. Chilly on Thursday with apparent temperatures spending most of the day in the lower 40s to around 50... break out the jackets and hot chocolate. The upper jet will be draped across the area and will be pulling in Pacific moisture which could easily keep skies mostly cloudy across the area Friday morning which would help to keep temperatures warmer. The trend has been for more clouds over the south and few clouds north so will stick close to that which will mean the first freeze for areas generally north of a line from Brenham to Conroe to Cleveland. The high slides off to the east Friday and Saturday which will lead to a slow warm up Friday night/Saturday with an increase in clouds. Not very confident that moisture will be sufficient and very weak dynamics for rainfall so have undercut the guidance numbers on rain chances significantly but in general the weekend should be warmer and more humid.

Side note... TDWR at THOU will be out of service through Dec 9th for major motor/drive service.

45

.MARINE...
A developing area of low pressure was located just south of Buoy 42019 early this morning, and this feature will result in elevated winds and waves across the coastal waters as it lifts to the northeast through the day. Expect offshore winds in the 15-25 knot range across the 0-60 NM waters today, but gusts to near gale force will be possible until the surface low clears the western Gulf later this afternoon. These winds will allow for waves 4-6 feet nearshore and 6-8 feet offshore, with occasional seas up to 10 feet. The ongoing Small Craft Advisory remains in effect through noon CST today, but may need to be extended with the morning update depending on how quickly wave heights decrease. Winds will still remain in the 15-20 knot range through tonight and caution flags will be needed for the 0-60 NM waters.

Periods of showers and thunderstorms will continue across the coastal waters today, with some storms possibly becoming strong to severe and producing hail, a waterspout or two, or gusty winds. Expect this activity to shift east of the waters later this afternoon with the surface low.

Otherwise, a strong cold front is expected to move off of the coast early Thursday morning. Strong offshore winds behind the front may gust to gale force by early Thursday morning through most of the day on Thursday.

Huffman

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 58 45 69 45 66 / 100 10 0 0 20
Houston (IAH) 60 49 70 46 69 / 100 10 0 0 10
Galveston (GLS) 64 58 68 58 70 / 100 10 0 0 10

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Flash Flood Watch until noon CST today for the following zones:
Brazoria...Chambers...Galveston...Harris...Liberty.

GM...SMALL CRAFT SHOULD EXERCISE CAUTION until noon CST today for the
following zones: Galveston Bay...Matagorda Bay.

Small Craft Advisory until noon CST today for the following
zones: Coastal waters from Freeport to the Matagorda Ship
Channel out 20 NM...Coastal waters from High Island to
Freeport out 20 NM...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...45
Aviation/Marine...14

[srainhoutx]

Just emptied 3.58 inches from the gauge for the weekend rainfall event here in NW Harris County...so far.

Looks like HGS is basing the lack of freezing temperatures on the GFS for Thursday night into early Friday. You can see the GFS indicates some mid and upper level clouds on the lower panel of the meteogram.

[srainhoutx]

Michael Ventrice ‏@MJVentrice · 1h1 hour ago  Medford, MA
Today's hot topic in weather will be arctic blast to intrude the lower 48. Focal region will be Rockies and Plains

[srainhoutx]

The 12Z GFS suggests the mid/upper level clouds may move out overnight Thursday into Friday making it a close call for the first freeze at IAH. We will see.

[christinac2016]

If I'm reading this right, I'm noticing maybe backing off of freezing temps later this week. My mind would like the cold, but my body doesn't like it. Guess that's what happens when you lose a lot of weight. Of course, my mom's main concern is what will be like on Christmas. She was disappointed at Thanksgiving.

[srainhoutx]

I believe Brooks mentioned mid December in his blog on KHOU.com today. The afternoon updated Climate Prediction Center Day 11+ Analogs suggest some of the memorable December analog dates and the temperature forecast into mid month supports additional cold air intrusions.