September 2016 - Cool & Drier To End Month

[Ptarmigan]

Daylight 8 year's ago this morning would bring scenes of complete devastation just E of Galveston, TX along the Bolivar Peninsula from Hurricane IKE. If IKE would have made landfall another 15-20 miles to the SW over W Galveston Island near Surfside; most of Galveston County, W and NW Galveston Bay, and the Houston Ship Channel would have had the devastating storm surge flooding.

Very heavy rains and gusty winds ongoing across Galveston County currently which will be moving into NE Brazoria County as a wet pattern arrives thanks to a weak GOM low that will continue to bring in tropical moisture each day through the weekend. So far a quick .75" of rain at the house.

Eight years later after Ike and no hurricane since than. Complacency grows.

[Katdaddy]

Scattered showers and thunderstorms approaching the coastal areas this morning as the pattern continues across SE TX with rain chances still likely to increase for the weekend.

[srainhoutx]

A very telling graphic from NWS Houston/Galveston regarding just how 'wet' we have been since 2015:

[tireman4]

000
FXUS64 KHGX 140953
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
453 AM CDT Wed Sep 14 2016

.DISCUSSION...
Weak ridging remains anchored over the state, with the highest
moisture ridging up over the western edge of the forecast area.
Widely scattered showers are forming in the northwestern Gulf
this morning and traveling westward within the easterly steering
flow pattern atop lower central Gulf pressure. The remainder of
this work week`s synoptic pattern is to take the Great Basin
upper low and pull in northeast over this weak southern Plains
ridging into the Northern Plains states by early Friday. The
precipitation forecast is pretty straight forward the next couple
of days; one of early day coastal showers with an isolated storm
/towering cumulus blossoming into further inland showers and
thunder as mid to upper 80 convective temperatures are achieved.
Higher eastern moisture will advect in the next few days and this
will equate to increasing cloudiness each subsequent day, easterly
breezes turning more onshore by late week. Periods of slightly
higher PV moving in upon easterlies will generate more shower/storm
areal coverage across the nearshore waters and this activity will
eventually transition to more inland convective coverage Friday.
Temperature behavior will be cut and paste over this last week of
summer; average middle 70 minimums/upper 80s to lower 90s maximums.

With autumn around the corner, the medium range models seem to be
struggling with run-to-run consistency in the evolution of the
long range solution. The GFS ensemble members, along with the
Canadian (CMC) solution and ECMWF to some degree, want to hang
back a broad trough west of the Rockies (behind the wake of this
current western CONUS open wave trough passage), eventually cutting
off a weak upper low across the Desert SW by early next week with
an elongated 590-ish 5H ridge extending from western Texas back
towards the southeastern U.S.. The solutions begin to diverge over
the last few days of the summer season. The more wet GFS/CMC retain
this broad western trough and take it slowly east while the drier
ECMWF holds this trough back and amplify the downstream ridge
over the Gulf/MS River Valley by mid week. A shallow trough passage
will keep any early week fropa from entering our region so little
to no change is expected in daily temperatures and onshore wind
behavior. The mid to long range forecast is a split between the
two aforementioned solutions; higher near coastal morning shower/storm
chances that will transition to moderate rain/thunder probs late
in the morning through late afternoon. This forecast leans towards
the drier ECMWF solution by the end of summer as upper ridging
wins out and keeps southern CWA slight POPS in place next Wednesday.
Autumn `16 officially commences at 9:21 AM LT next Thursday. 31

&&

.MARINE...
East winds 10-15kt (maybe a touch higher at night) and 3-4ft seas
should persist thru Thurs. Tides still running 1.0-1.5ft above
normal along the upper Tx coast which is putting water close, or up
to the the HWY 124/87 intersection a few hours before/after times of
high tide. No problems expected elsewhere. Highest tide of the day
is around 345am today. Levels should steady out, then fall later
this afternoon. They should peak roughly around the same level at
410am the Thurs morning high tide w/ maybe a little higher wave
runup.

Winds gradually veer more to the SE/S Friday into this weekend with
speeds/seas likely remaining below caution criteria. Water levels,
though remain slightly above normal, should fall enough whereas
Bolivar water levels aren`t an issue anymore. 47

&&

.AVIATION...
Iso/sct precip ongoing near the coast and offshore. Though anticipate
some iso activity further inland w/ daytime heating...guidance indicates
less coverage than we`ve seen the past several days so will probably
leave out the mention of precip in some of the 12z TAFs. Repeat scenario
tonight & Thurs. 47

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 92 74 93 74 90 / 20 10 20 10 50
Houston (IAH) 91 75 92 75 90 / 20 20 20 20 50
Galveston (GLS) 89 80 87 80 86 / 40 30 30 40 50

&&

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

$$

Discussion...31

[worrybug]

Very heavy rains and gusty winds ongoing across Galveston County currently which will be moving into NE Brazoria County as a wet pattern arrives thanks to a weak GOM low that will continue to bring in tropical moisture each day through the weekend. So far a quick .75" of rain at the house.

I'm kinda bothered by this GOM low, Katdaddy. Could we be looking at another April 18th type of situation? And how stout is this low, anyway?

[srainhoutx]

Wednesday evening briefing from Jeff:

Low pressure located over the FL Keys and SE Gulf of Mexico this past weekend has meandered into the central Gulf of Mexico where showers and thunderstorms have developed.

Visible satellite images along with buoy and oil rig observations indicate a broad and weak area of low pressure has developed over the central Gulf of Mexico offshore of the Louisiana coast. This has resulted in winds turning NNE to NE over SE TX today and increasing. Showers and thunderstorms while more concentrated than the last few days remain fairly disorganized and surface pressures are not falling at this time. The National Hurricane Center gives the area a 10% chance of development over the next 5 days as it drifts toward the middle to lower TX coast.

Deep tropical moisture associated with this feature will begin to move inland over SE TX late Thursday and remain in place Friday-weekend. Showers and thunderstorms will significantly increase in coverage Friday-Sunday as bands of rainfall sweep inland from the Gulf. High moisture levels will support heavy rainfall potential of 1-3 inches per hour which could lead to localized street flooding.

Tides:
NE winds in the 15-20mph range across the NW Gulf is resulting in sea water rise along the coast. Tidal forecast for the next 72 hours show a steady increase in tide levels as wave heights increase and winds remain out of the NE which is a highly favorable tidal increase for the upper TX coast. Current forecasts show water levels reaching 3.0-3.3 ft above MLLW (barnacle level) starting on Thursday and into the weekend. This is generally below flood threshold levels, but given wave action on top of the water level rise, some minor flooding will be possible at times of high tide.

Aside:
If one ever wanted to know how we would make up all the of the rainfall lost in the many back to back years of drought from 2009-2014…this is one way. Since January 1, 2015 the City of Baytown has recorded a staggering 167.75 inches of rainfall or 67.07 inches above normal.

[Skyguy]

Wednesday evening briefing from Jeff:

Low pressure located over the FL Keys and SE Gulf of Mexico this past weekend has meandered into the central Gulf of Mexico where showers and thunderstorms have developed.

Visible satellite images along with buoy and oil rig observations indicate a broad and weak area of low pressure has developed over the central Gulf of Mexico offshore of the Louisiana coast. This has resulted in winds turning NNE to NE over SE TX today and increasing. Showers and thunderstorms while more concentrated than the last few days remain fairly disorganized and surface pressures are not falling at this time. The National Hurricane Center gives the area a 10% chance of development over the next 5 days as it drifts toward the middle to lower TX coast.

Deep tropical moisture associated with this feature will begin to move inland over SE TX late Thursday and remain in place Friday-weekend. Showers and thunderstorms will significantly increase in coverage Friday-Sunday as bands of rainfall sweep inland from the Gulf. High moisture levels will support heavy rainfall potential of 1-3 inches per hour which could lead to localized street flooding.

Tides:
NE winds in the 15-20mph range across the NW Gulf is resulting in sea water rise along the coast. Tidal forecast for the next 72 hours show a steady increase in tide levels as wave heights increase and winds remain out of the NE which is a highly favorable tidal increase for the upper TX coast. Current forecasts show water levels reaching 3.0-3.3 ft above MLLW (barnacle level) starting on Thursday and into the weekend. This is generally below flood threshold levels, but given wave action on top of the water level rise, some minor flooding will be possible at times of high tide.

Aside:
If one ever wanted to know how we would make up all the of the rainfall lost in the many back to back years of drought from 2009-2014…this is one way. Since January 1, 2015 the City of Baytown has recorded a staggering 167.75 inches of rainfall or 67.07 inches above normal.

You'd think the greater danger for heavy rains would be in S. Texas, since that's where the Low's going to make landfall, anyway.

[redneckweather]

Don't think there will be danger with this system wherever it comes ashore. It will probably be nothing more except a surge of moisture all up and down the Texas coast. I wouldn't mind some rain right about now.

[BiggieSmalls]

Any hope for a "real" cold front by...early October even?

[tireman4]

From HGX AFD:

( Items concerning the tropics are on the Tropical Weather Thread)


DISCUSSION...
Influences of the low pressure area to our southeast in the Gulf
will complicate the forecast from now into the weekend,
particularly as it relates to precip chances and sky cover. Next
week, as ridging builds in, we should see a drying trend into most
of the week, and temperatures should nudge upwards slightly.

Today through Monday...
This afternoon looks to be very much like yesterday, with
scattered showers and storms over the waters and immediate coast,
but only a speckling of light convective showers farther inland.
This should continue, with temperatures maxing out somewhere in
the low 90s for most. As a quick flashback, yesterday`s forecast
did expect greater convective coverage today - but with a
circulation developing over the low pressure area in the Gulf,
winds have been more northeasterly today, and only recently
veering to become more onshore.

uesday through Thursday...
A backdoor front looks to dip in from the north/northeast on
Tuesday, but considerable uncertainty remains about how deep it
will drift before stalling out. Aloft, ridging looks to build in,
and the combination of decreasing moisture (precipitable water
may even dip below 1.5 inches up north) and a more stable column
should trend precip chances downwards as the week grows older.
Along with this, we should see temperatures move from just shy of
90 back to just above 90 degrees in the afternoons. However,
overnight lows may be able to dip slightly lower as well.

One complicating factor remains at the end of the forecast period,
and that is the fate of the any stalled front. If it does push
over the water, as now the GFS and Euro both decidedly do, any
remnant vorticity could spin up and change things up. Indeed, this
does happen in both the Euro and GFS, but does so far to the east,
and moves any vort max and its attendant precip potential
northward into Louisiana. Given the time of year, this is
not a feature to ignore, but it also should not cause any
consternation or alarm at this point, as a significant number of
factors must fall into place just right.

[jasons2k]

Rain since laying sod on Saturday: 0.00"

So much for a wet week.

[TexasBreeze]

Tuesday, the only day, not much from that shower either for this "wet week". I could see just coastal areas getting anything the next few days too....

[Skyguy]

Don't think there will be danger with this system wherever it comes ashore. It will probably be nothing more except a surge of moisture all up and down the Texas coast. I wouldn't mind some rain right about now.

Well, I'd say the only area that has anything to worry about, TC-wise, is between Brownsville and Corpus Christi. The shear is much lower south of west. What do you think, Redneckweather? Accurate or inaccurate?

[worrybug]

Folks, if that thing in the Gulf of Mexico that NHC has a 20% chance of development continues to sit there and brew I'm going to worry-----I'm already starting to worry. One of your forum members is already calling it Alicia part deux! Say it ain't so.

[Skyguy]

Folks, if that thing in the Gulf of Mexico that NHC has a 20% chance of development continues to sit there and brew I'm going to worry-----I'm already starting to worry. One of your forum members is already calling it Alicia part deux! Say it ain't so.

Guys, can anyone tell me what exact direction that low is going? Where will landfall occur if it stays on its present course?

[sau27]

Folks, if that thing in the Gulf of Mexico that NHC has a 20% chance of development continues to sit there and brew I'm going to worry-----I'm already starting to worry. One of your forum members is already calling it Alicia part deux! Say it ain't so.

Guys, can anyone tell me what exact direction that low is going? Where will landfall occur if it stays on its present course?

Right at your front door.

But really, I think it has been said here already if it were to drift in a more northerly direction shear would rip it apart.

[Ounce]

Folks, if that thing in the Gulf of Mexico that NHC has a 20% chance of development continues to sit there and brew I'm going to worry-----I'm already starting to worry. One of your forum members is already calling it Alicia part deux! Say it ain't so.

It ain't so. 80% chance of non-development. Shouldn't you have already bought all of your hurricane supplies back in June?

You NEED to read what Srain has said about it and chill. Alicia was at the tail end of a cool front that blew through and fizzled in the Gulf. The present conditions are not the same as when Alicia was formed.

Worry about something worthwhile. This ain't it. This ain't even an April 18 thing. Or a Katrina thing. If you don't believe that, then check out what the NWS office released, tonight.

National Weather Service Houston/Galveston TX
917 PM CDT Thu Sep 15 2016

.DISCUSSION...

Higher chances for precipitation should remain along the coastline
this evening and overnight. Surface low pressure situated over
the Western Gulf will move westward over night and gradually evolve
into a coastal trough which should help focus precipitation between
08 to 10Z over mainly the coastal counties. Water vapor imagery
shows a weak upper level trough situated over the Western Gulf, and
its orientation should help to bring increased moisture levels this
weekend.

[worrybug]

Folks, if that thing in the Gulf of Mexico that NHC has a 20% chance of development continues to sit there and brew I'm going to worry-----I'm already starting to worry. One of your forum members is already calling it Alicia part deux! Say it ain't so.

It ain't so. 80% chance of non-development. Shouldn't you have already bought all of your hurricane supplies back in June?

You NEED to read what Srain has said about it and chill. Alicia was at the tail end of a cool front that blew through and fizzled in the Gulf. The present conditions are not the same as when Alicia was formed.

Worry about something worthwhile. This ain't it. This ain't even an April 18 thing. Or a Katrina thing. If you don't believe that, then check out what the NWS office released, tonight.

National Weather Service Houston/Galveston TX
917 PM CDT Thu Sep 15 2016

.DISCUSSION...

Higher chances for precipitation should remain along the coastline
this evening and overnight. Surface low pressure situated over
the Western Gulf will move westward over night and gradually evolve
into a coastal trough which should help focus precipitation between
08 to 10Z over mainly the coastal counties. Water vapor imagery
shows a weak upper level trough situated over the Western Gulf, and
its orientation should help to bring increased moisture levels this
weekend.

Well, even at that, we could still be looking at some nasty storms. Or maybe not?

[Ounce]

Folks, if that thing in the Gulf of Mexico that NHC has a 20% chance of development continues to sit there and brew I'm going to worry-----I'm already starting to worry. One of your forum members is already calling it Alicia part deux! Say it ain't so.

It ain't so. 80% chance of non-development. Shouldn't you have already bought all of your hurricane supplies back in June?

You NEED to read what Srain has said about it and chill. Alicia was at the tail end of a cool front that blew through and fizzled in the Gulf. The present conditions are not the same as when Alicia was formed.

Worry about something worthwhile. This ain't it. This ain't even an April 18 thing. Or a Katrina thing. If you don't believe that, then check out what the NWS office released, tonight.

National Weather Service Houston/Galveston TX
917 PM CDT Thu Sep 15 2016

.DISCUSSION...

Higher chances for precipitation should remain along the coastline
this evening and overnight. Surface low pressure situated over
the Western Gulf will move westward over night and gradually evolve
into a coastal trough which should help focus precipitation between
08 to 10Z over mainly the coastal counties. Water vapor imagery
shows a weak upper level trough situated over the Western Gulf, and
its orientation should help to bring increased moisture levels this
weekend.

Well, even at that, we could still be looking at some nasty storms. Or maybe not?

Good chance of rain. Not biblical rain. Not April 18 rain. Not cyclonic rain. The NWS hasn't even forecasted greater than 50% chance of rain.

Chill, just like TexasPirate said in the other thread.

[Katdaddy]

As expected, the NW GOM tropical disturbance has diminished overnight. Tropical moisture will move into the Upper TX Coast as the weak low drifts toward the TX Coast today through tomorrow. TD 12 is now TS Karl in the E Atlantic over the open waters. The next named storm will be Lisa.

From this morning's Houston-Galveston Hazardous Weather Outlook:

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT

SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY. SLOW MOVING CLUSTERS OF STORMS MAY PRODUCE HEAVY RAIN IN A SHORT PERIOD OF TIME AND MAY CAUSE LOCALIZED STREET FLOODING. AREAS GENERALLY ALONG AND SOUTHEAST OF HIGHWAY 59 ARE POSITIONED IN A SLIGHTLY MORE FAVORABLE AREA FOR THESE LOCALIZED STRONGER CELLS. LIGHTNING AND 20 TO 35 MPH WIND GUSTS WILL ALSO BE POSSIBLE IN AND NEAR STORMS.