August 2016: Rain Chances Continue.

[MontgomeryCoWx]

Yeah, I remember reading the discussions last week and over the weekend, and they predicted this week to be hot & dry, with a return to a more moist pattern - at least typical 20-30% showers - starting back today. They even mentioned a few waves could gives us some more heavy rain threats. I haven't read the last few days, but it appears this has now changed for the worse. Other than a little break tomorrow, it looks like the hot & dry pattern is here for awhile as the ridge holds in place. Boo-hiss!

Yep, I loathe Summer here. I'm ready for mid October.

[A.V.]

Yeah, I remember reading the discussions last week and over the weekend, and they predicted this week to be hot & dry, with a return to a more moist pattern - at least typical 20-30% showers - starting back today. They even mentioned a few waves could gives us some more heavy rain threats. I haven't read the last few days, but it appears this has now changed for the worse. Other than a little break tomorrow, it looks like the hot & dry pattern is here for awhile as the ridge holds in place. Boo-hiss!

It hasn't worsened all that much (as of time of writing); rainfall still looks to continue next week, and I have my suspicions that the high pressure moves, just not as coordinated as tracked by models. It might be 'eratic;' they will trend drier just because the high pressure hasn't moved, but it can suddenly take exit left, upping rain chances.

[A.V.]

Summer storms were far easier to come by in the previous decade. I don't think lengthy periods of dryness are normal at all for Coastal Texas.

[srainhoutx]

Will need to monitor for a potential Tropical Troublemaker organizing off the Northern Gulf mid next week. The Global models are suggesting the upper Ridge breaks down and lowering heights/pressures become established over our Region in about a week as a vigorous trough moves East across the Central United States.

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08042016 21Z 7 Day QPF p168i.gif

[jasons2k]

Yeah, the models look better (somewhat) if you want rain. At least we have 30/40 pops most days instead of 10/20.

[DoctorMu]

Summer storms were far easier to come by in the previous decade. I don't think lengthy periods of dryness are normal at all for Coastal Texas.

Unfortunately, the long periods without rainfall have become "normal." Trees stressed by the severe 2011 drought are still susceptible leaf drop or worse...I can see the chlorophyll leaching out of some. Sprinklers will be on full throttle tonight.

[DoctorMu]

Yeah, the models look better (somewhat) if you want rain. At least we have 30/40 pops most days instead of 10/20.

East of I-45 looks promising.

Need the trend to enhance to provide relief for CLL. Rain chances have crept up to 20% Mon-Thursday. We'll see.



Area Forecast Discussion
National Weather Service Houston/Galveston TX
341 PM CDT THU AUG 4 2016

.DISCUSSION...
Another toasty day today, with most of the showers remaining over
the waters and along the coastal areas. These warm and muggy
conditions will persist throughout the weekend and into early next
week, keeping heat indices between 104-107.

Tomorrow, shower coverage will increase slightly over the waters,
and begin to move inland in the late morning and throughout the
afternoon. The seabreeze circulation along with an increase in
moisture in the vertical will help aid the development of these
scattered showers, as the summer time regime continues.

Our next disturbance moving in from the East will bring the
greatest chance for POPs on Sunday afternoon. The blob of high
pressure that has remained over us for this last week will begin
to lose control of the pattern. This will lead to height falls
across the region. Lower pressure will help to enhance surface
convergence and provide lift across much of the coastal areas and
eastern edge of our zones. These locations will see the best
chance for precipitation on Monday and Tuesday. Rain chances will
diminish into Wednesday and sea breeze circulations will once
again drive our chances for precipitation.

[Katdaddy]

Perfect blue skies earlier but when I took another sky check I saw what looked to be cirrus but they were not right. So much lower than a cirrus canopy would ever be as well as clear radar. My first thought was smoke and checked the satellite time lapse and saw what looked like a small cirrus stream develop across the coast which is indicative of a fire. The Houston-Galveston NWS verified the wild fire ongoing in Galveston County along the coast about 20 miles SSE of League City.

[srainhoutx]

Seeing a bit more scattered storm activity over the Coastal Waters this morning compared to yesterday and expect isolated pulse showers and storms to increase along the seabreeze as it moves inland with a bit more in the way of Gulf moisture. We could flirt with Heat Advisories during the weekend, so stay hydrated.

Attention then turns to our East where an area of low pressure and potential tropical development may occur early next week. Locally we will need to watch for an storms dropping SW around the periphery of the Upper Ridge situated over West Texas.

08052016 8AM EDT two_atl_5d0.png

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT FRI AUG 5 2016

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Tropical
Storm Earl, located over the southern Bay of Campeche.

1. A trough of low pressure is expected to form over the northeastern
Gulf of Mexico late in the weekend or early next week. Some
subsequent development of this system is possible while it remains
nearly stationary.
* Formation chance through 48 hours...low...near 0 percent
* Formation chance through 5 days...low...20 percent

Forecaster Avila

[srainhoutx]

On this day 8 years ago TS Edouard made landfall in Gilchrist and developed very close to home with little in the way of preparation time. Let these close to home developing Tropical Cyclones serve as a reminder that now is the time to prepare and we often do not have days to follow the progress of developing Tropical Cyclones. #ItOnlyTakesOne #HurricaneStrong

08052016 Edouard 2008 CpFv5C0WYAAn6Lm.jpg

NWS Houston ‏@NWSHouston · 2h2 hours ago
Today in weather history Tropical Storm Edouard made landfall in 2008 near Gilchrist, TX #txwx #houwx pic.twitter.com/StEMc3X6r

[srainhoutx]

08052016 mcd0525.gif

MESOSCALE PRECIPITATION DISCUSSION 0525
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
920 AM EDT FRI AUG 05 2016

AREAS AFFECTED...EASTERN FL PANHANDLE/WEST-CENTRAL FL COAST...

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 051320Z - 051750Z

SUMMARY...EARLY MORNING CONVECTION CONTINUES TO FIRE IN RESPONSE
TO A WEAK/PERSISTENT BAND OF MID-LEVEL VORTICITY ACROSS THE
NORTHEASTERN GULF OF MX. DEEP TROPICAL MOISTURE REMAINS OVER THE
REGION WITH PWATS OVER 2.25" ACROSS MUCH OF THE NORTHERN HALF OF
FL. VERY WEAK STEERING FLOWS SHOULD ALLOW FOR SLOW MOVING
CONVECTION WITH CELL MERGERS INCREASING THE RISK FOR FLASH
FLOODING.

DISCUSSION...VISIBLE IMAGERY THIS MORNING SHOWED SEVERAL
CONVECTIVE COMPLEXES ERUPTING ALONG THE NORTHWEST FL COAST. THE
12Z SOUNDING FROM TLH INDICATED DEEP TROPICAL MOISTURE IN PLACE
WITH PWATS NEARING 2.50 INCHES. ADDITIONALLY...TALL/SKINNY CAPE
PROFILES WERE NOTED COUPLED WITH VERY WEAK TROPOSPHERIC FLOW AND
FREEZING LEVELS ABOVE 15 KFT. ALL OF THESE INGREDIENTS SUPPORT
HEAVY RAINFALL ACROSS THE AFFECTED REGION. WHILE MOST OF THE CB
TOWERS WERE LOCATED ALONG THE COAST OR JUST OFFSHORE...VAD WIND
PROFILER DATA SHOWED DECENT LOW-LEVEL WESTERLY FLOW WHICH SHOULD
DRAW SOME OF THESE STORMS INLAND. AS OF 13Z...THE PROFILER DATA
INDICATED 10 TO 15 KNOTS OF WESTERLY FLOW IN THE 3000 TO 6000 FT
LAYER. THERE DOES NOT APPEAR TO BE ANY NOTABLE INHIBITION IN THE
RAP OBJECTIVE ANALYSIS WHICH IS BEING VERIFIED BY THE FREE
CONVECTION OCCURRING OVER MUCH OF THE NORTHEASTERN GULF OF MX.

AS USUAL...THE FLASH FLOOD GUIDANCE VALUES ARE RATHER HIGH OVER
THE REGION WHICH WOULD MAKE EXCEEDANCE OF THESE NUMBERS DIFFICULT.
HOWEVER...ANY ORGANIZED/SLOW-MOVING CELLS WITHIN THIS EXTREMELY
HIGH PWAT/WEAK SHEAR ENVIRONMENT CAN PRODUCE HEAVY DOWNPOURS
CAPABLE OF FLASH FLOODING.

THERE IS A DECENT SIGNAL IN THE CAMS FOR ORGANZED HEAVY RAINFALL
OVER THE REGION...PARTICULARLY ALONG THE COAST WHERE LOW-LEVEL
CONVERGENCE WILL BE MAXIMIZED. THE 00Z NSSL-WRF CONFINES THE
ACTIVITY TOWARD THE SOUTH WHILE THE LATEST HRRR/HRRR-PARALLEL SEEM
TO EVENLY DISTRIBUTE THE CONVECTION ALONG THE COAST.


RUBIN-OSTER

ATTN...WFO...JAX...TAE...TBW...

[djmike]

Which way will it drift?

[Katdaddy]

The sea breeze has worked its way inland across the TX coastal plains today and is now well inland this evening. The NE GOM will be watched closely this weekend and through next week as there is a potential for tropical development. The current forecast keeps the disturbed weather in the NE GOM. This is a prime example of how close to home development can occur and the GOM waters are very warm.

[Andrew]

Not seeing much development tropical wise for the gulf/Caribbean over the next week or two besides what happens over the northeastern part of the gulf. Rain chances should increase though during the middle/late part of the week as deeper moisture is fetched from the central and eastern part of the gulf/Caribbean. Otherwise expect more of the same, warm and muggy with some isolated afternoon showers possible.

[DoctorMu]

After a slew of 98°F and 99°F days, tomorrow should reach the Century mark, where the highs will stay for the next week. Slight chance of rain Mon, Tue, Thursday, and Saturday.

[srainhoutx]

There may be a glimmer of hope regarding our rain chances and a break from the heat by next weekend, but I would like to see a bit more consistency in the guidance before buying what the computer models are selling in the Medium Range. The ECMWF is suggesting the unsettled weather to our East over near Northern Florida will meander Westbound across the Northern Gulf Coast throughout the coming workweek and approach our Region next Saturday. The ECMWF Ensembles are in somewhat agreement while the GFS and its Ensembles are less bullish on those modeled rain chances. If the ECMWF is correct, the Upper Ridge would relax over Texas allowing for cooler temperatures and unsettled weather as deep tropical moisture increases along with instability. There are also suggestions of a weak frontal boundary nearing the Red River Valley of North Texas as a vigorous shortwave trough advances East across the United States. Later in the week we will look at the potential of how those re curving Tropical Cyclones in the Western Pacific may influence the Northern Hemisphere upper air pattern and any potential sensible weather impacts for our Region. Fingers crossed that those that have not seen much...if any rainfall since June will get their chance before long.

08072016 00Z 144 ecmwf_uv850_vort_us_7.png

08072016 00Z 144 ecmwf_z500aNorm_us_7.png

08072016 00Z 192 ecmwf_z500aNorm_namer_9.png

Edit to add the morning Updated Super Ensemble Day 8+ Analogs are suggesting a bit of a weakness over Texas as the Upper Ridge shifts both West and East indicated by the "+" signs meaning higher heights, or building High Pressure over the Great Basin and the SE United States. The Super Ensembles are updated each morning around 9:00AM local time, so we will continue to monitor for any subtle changes throughout the coming week.

08072016 Day 8+ Analogs 500hgt_comp_sup610.gif

[srainhoutx]

the 12Z GFS has trended the way of the 00Z ECMWF suggesting a somewhat complicated forecast challenge as the mid/upper level remnants of Eastern Pacific Tropical Storm Javier turn right or toward the Southern Rockies/Southern Plains with an approach trough and the area of unsettled weather over the Northern/NE Gulf meander Westbound.

[srainhoutx]

The 12Z ECMWF suggests enhanced rainfall chances next weekend. Fingers crossed!

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[srainhoutx]

Sunday afternoon briefing from Jeff:

Overall routine summer pattern in place over the region with high pressure aloft and weak high pressure over the NW Gulf keeping temperatures hot and rain chances low.

Overall pattern will slowly change this week as the high pressure ridge over TX begins to break down and shift westward…especially by the end of the week. Edge of the current ridging over central LA early this afternoon depicts the region where thunderstorms have begun to develop (roughly from deep E TX southeast toward the central LA coast). Further east a trough of lower pressure is located over the NE Gulf of Mexico and north FL. Meso scale models show current activity in the Sabine River Valley attempting to move SSW/SW this evening and may impact our far eastern counties with a few storms. Models…especially the TX TECH WRF show an even better chance on Monday with activity approaching from the NE and moving deeper into the area…not sure if the ridge will give as much ground as this model is suggesting, but will need to keep an eye out toward the NE for any organized convection that may attempt to move into the area.

Bigger changes appear at least possible toward the end of the week into next weekend as ridging appears to get broken down by an incoming trough in the Pac NW which appears possibly strong enough to even send a weak frontal boundary into the state. At the same time both the EURO and GFS are starting to trend toward the NE Gulf of Mexico surface trough moving westward as high pressure builds over the SE US. This would allow a significant increase in moisture by next weekend over the region with much lower heights aloft and possibly some sort of frontal boundary somewhere over the state. While confidence is certainly low with regard to any frontal boundary this time of year, the pattern does support cooler temperatures and much better rain chances next weekend into the start of the following week.

[Ptarmigan]

NWS Fort Worth

000
FXUS64 KFWD 071723
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
1223 PM CDT SUN AUG 7 2016

.AVIATION...
VFR conditions will prevail through the period with winds
fluctuating between SW and SE at 10 kts or less. Scattered showers
and thunderstorms are possible across eastern TX this afternoon
but this activity will be well east of area TAF sites. Additional
thunderstorms are possible on Monday afternoon closer to the DFW
Metroplex, but will refrain from including any mention in the
extended DFW TAF for now as the potential is too low.

-Stalley

&&


.PREV DISCUSSION... /ISSUED 319 AM CDT SUN AUG 7 2016/
The upper level ridge will continue to largely control the
weather this week but a front looks probable by the weekend.

Hot and humid conditions will continue for the next few days
across much of North and Central Texas with highs from 98-104
degrees and overnight lows in the mid to upper 70s in most
places, but in the low 80s in the urban areas of the DFW
Metroplex. Have expanded the Heat Advisory to include Montague,
Wise, Jack, and Young counties, but have decided not to extend
into Monday at this time. While some places may reach Heat
Advisory criteria on Monday, would like to further assess how
widespread 105-108 heat index values will be on Monday. The
reality may be that only isolated locations reach 105-108 degrees
while most of the region remains 100-105 degrees. Either way, it
will be hot again on Monday. This afternoon/evening and Monday
afternoon/evening, there continues a low chance for showers and
isolated thunderstorms across our eastern counties. On Monday
morning, there may be a few showers across our north and northeast
counties.

On Tuesday, most of the models develop a weak upper level low under
the ridge, just northwest of our CWA. This weak low appears to be
a piece of energy that is traveling around the top of the ridge
and breaks off. The models do not explicitly develop convection
across the region, but with this weakness aloft would not be
surprised to see a few showers or storms develop across parts of
the region during the peak afternoon and evening hours. Moisture
will still be the best across our eastern counties on Tuesday, and
forecast soundings still show fairly dry air in the mid levels
indicative of the upper level ridge overhead, but will include a
mention of low chances for isolated convection on Tuesday.

The weak upper level low quickly vacates the area by Wednesday,
and Wednesday and Thursday will be very similar to each other with
hot temperatures and a low chance of rain in the eastern counties.

We may get a break from the heat and a more promising chance for
rain by the weekend as the upper level ridge is squashed south by
a trough moving east across the country. The GFS is stronger with
this trough as it crosses the Plains and develops farther south
into the Southern Plains on Saturday. The ECMWF still has evidence
of this trough sliding into the Southern Plains, but is weaker
and slower with the timing. This pattern change allows a cold
front to slide into our area and with that will come a chance for
rain. Based on the latest guidance, timing of the front is on
Saturday with the best chances for rain that same day.

JLDunn


http://forecast.weather.gov/product.php ... glossary=1

Cold front could come this weekend. That could bring rain.