Texas/New Mexico/Louisiana/Mexico Obs And Discussion Thread Part 5

[msp]

crazy burst of gusty winds here in Houston.  looks like a potent OFB from the storms to the east

[Srain]

Morning Update from Jeff:

 

Chance of daily thunderstorms for the next several days.

 

Extremely moist air mass pushing into the area this morning as Gulf of Mexico surface trough inches toward the TX coast. Radar shows some offshore activity ongoing currently and there is some hint of spin south of the Louisiana coast, likely in the mid levels. LCH sounding showed a PW of nearly 2.4 inches last evening which is 2 standard deviations above normal for late August. Models bring this very moist air mass into SE TX today especially from I-10 southward, while dry air attempts to entrain across our northern counties from the ENE.

 

Given the increasingly extremely moist air mass in place it will not take much heating to set things off today. Interestingly several of the meso models do not show thunderstorm development until later in the afternoon and this is similar to what happened yesterday over Louisiana. Not sure how exactly things will play out today as low trigger temperatures suggest an earlier in the day formation of storms while the models are pointing toward later. Moist tropical air mass will be very capable of some fairly impressive short term rainfall rates under the stronger storms with hourly totals of 1-3 inches possible.

 

Wed-Fri:

Not real sure how to handle this period as Gulf surface trough may attempt to develop into a weak surface closed low and move W or WSW toward the TX coast. TX TECH short range model shows this well along with a couple other models. Should a broad surface low form over the NW Gulf, will probably need to realign rain chances toward the coast and offshore as SE TX would lie on the northern edge of any circulation field. Not overly confident in this happening just yet to reduce rain chances on Wednesday and Thursday especially given the very moist air mass pouring into the region. NHC mentions this potential in their 700am CDT tropical weather outlook and places the development chance at 10%.

 

Extended (Fri-Mon):

Upper level trough over the western US will slowly progress into TX with large scale lift increasing over the region and a moist air mass remaining in place. Still could have some sort of tropical low moving inland along the TX coast Friday-Saturday….but again this is highly uncertain. Upper trough alone with tropical moisture will produce a good chance of thunderstorms over the weekend with some very heavy rainfall possible. Any tropical disturbance will only complicate things.

 

Tropics:

Hurricane Cristobal is lifting out NE of the Bahamas this morning after becoming the 3^rd hurricane this season. The hurricane should lift NE through Thursday on the NW side of the developing sub-tropical ridge.

 

Low Level Pattern Shift:

Deep layer trough that has captured Cristobal over the western Atlantic has upset the normal trade wind pattern out of the deep tropics with the mean trade winds blowing SE to NW just east of the Caribbean Sea in a pattern more similar to late fall than late August. As Cristobal and this trough lifts out over the next 48 hours and sub-tropical ridging builds back westward the easterly trades will become re-established from the Atlantic into the Caribbean Sea….this is known as a trade wind burst. On the leading edge of such bursts, low level mass convergence or converging air at the surface helps to lead to developing convection and lowering pressures. This pattern is what led to the formation of the now infamous Hurricane Sandy (2012) over the western Caribbean. Global forecast models are starting to suggest surface pressures lowering from the central into the western Caribbean Sea this weekend into early next week and then into the Gulf of Mexico next week. There is potential for tropical cyclone development out of this pattern next week over the western Caribbean Sea or Gulf of Mexico.

 

African Wave:

A strong tropical wave will be moving off the west coast or Africa over the next few days and conditions appear favorable for development of this wave as it moves westward over the tropical Atlantic.

 

[wxmx]

S TX/NE MX may see a TD or weak TS landfall tonight around midnight. It should be very small, so I expect any impacts be very limited.

[Srain]

Morning Update from Jeff: (HCFCD):

 

Increasing threat for excessive rainfall Friday into Saturday.

 

Surface low located over the western Gulf of Mexico just east of Brownsville will slowly move inland today allowing a plume of very moist air to spread inland from the coast. Brownsville radar indicates that thunderstorms have erupted over/near the center of the circulation this morning. Currently this moist plume extends about 25-30 miles inland and is clearly marked by ongoing thunderstorms over the nearshore waters and coastal counties. As the circulation with 98L gradually dissolves this will open the door to better inland penetration of moisture and thunderstorms starting this afternoon. Still expect a strong rainfall gradient today from the coast inland to roughly I-10 or HWY 105 with our northern counties seeing very little rainfall and the coastal areas possibly picking up a couple of much needed inches.

 

Forecast gets more interesting Friday-Saturday as an approaching long wave trough over the western US will help to steer the remains of 98L northward toward SE TX/SW LA while a secondary surge of very moist air (PWS at or above 2.5 inches which is +2 SD above normal for late August) just north of the Yucatan moves NW toward the TX coast. Weak large scale ascent will be present from Friday afternoon into Saturday supporting widespread thunderstorms. I am concerned with a few of the models showing some fairly organized thunderstorms as the vort lobe with 98L moves into or just east of SE TX early Saturday morning. Organized thunderstorms in such a moist air mass would be very capable of “incredible” rainfall rates of 3-5 inches per hour. Rainfall rates of this magnitude would cause flooding even in areas that are running a significant rainfall deficit currently.  

 

Late Weekend/Early Next Week:

Trough axis begins to push eastward Sunday helping to dry out an extremely moist air mass, but another strong tropical wave will already be approaching from the central Caribbean Sea by this time. This wave is a function of a trade wind burst behind the currently departing Hurricane Cristobal over the NW Atlantic. This trade wind burst is allowing strong surface mass convergence on its leading edge, but currently 30kts of upper level WSW shear is keeping the system from organizing. As the wave/wind burst moves westward toward the western Caribbean Sea upper level conditions appear to become favorable for development. The GFS, GFS Ensembles, and CMC all show a closed low tropical system in the southern Gulf of Mexico/Bay of Campeche early to mid next week. There appears to be enough ridging over the US Gulf coast to keep any tropical system moving WNW or NW toward MX or S TX, but models are starting to point at somewhat of an elongated system with impacts sprawling outward NE from the center well up the TX coast.   

 

Tides:

Winds have sustained in the 15-20mph range overnight and will gradually weaken and veer to the ESE to SE today as the surface low east of Brownsville weakens and shifts inland. Current tides are running 1-2 feet above normal and expect this to continue today. Buoy 20 E of Galveston is running 3.0 ft swell with a 4.1 second period which is down from yesterday, so not expecting any more water to be brought to the coast by wave action. With winds veering from NE to ESE/SE today expect the mean transport of water toward the coast to gradually end also.

 

Current Water Levels:

 

Galveston Bay North Jetty: 2.41 ft

Galveston Pier 21: 2.08 ft

Eagle Point: 1.75 ft

Morgan’s Point: 1.50 ft

Lynchburg Ferry Landing: 1.32 ft

Freeport: 1.96 ft

Sargent: 1.23 ft

Rollover Pass: 1.53 ft

Sabine Pass: 1.53 ft

 

[Chinook]

Is this a bird migration? There are clear skies reported in W Texas and New Mexico, with no dust reported and light winds. The AMA radar says there is 35 dbz of reflectivity. This also shows up on LBB and FDX, so it is not a malfunctioning radar.

 

 

 

 

[Quixotic1]

Is this a bird migration? There are clear skies reported in W Texas and New Mexico, with no dust reported and light winds. The AMA radar says there is 35 dbz of reflectivity. This also shows up on LBB and FDX, so it is not a malfunctioning radar.

 

2014_08_28_1750z_AMA.png

Insects? That's happened but usually during FROPA

[Srain]

Morning Update from Jeff:

 

Heavy Rainfall possible next 36 hours.

 

Tropical cyclone formation possible this weekend/early next week W Caribbean Sea/southern Gulf of Mexico

 

A plume of extremely deep tropical moisture with PWS of 2.3-2.5 inches is heading for the upper TX coast and SW LA coast this morning. A complicated surface pattern has developed with the old surface low we have been tracking now for days located midday between Corpus Christi and Brownsville this morning resulting in ongoing flooding in that region. A secondary weak circulation has now developed over the central Gulf of Mexico and is moving quickly toward the upper TX/SW LA coast at this time. The leading edge of this system is clearly seen on Houston radar across the offshore waters with a strong leading squall (ie note all the marine warnings in effect). This initial squall in racing NNW at over 45mph and producing frequent wind gust to over 50mph (Note: Apache Oil Platform KXIH just gusted to 30kts just SE of Galveston) . It should reach the coast within the next hour and then begin to spread inland.

 

Additionally, a trough axis is slowly approaching the area from the WNW with ongoing thunderstorms over NW and NC TX and outflow boundaries moving SE toward SE TX which will act to add another mechanism for lift on this very moist air mass needing little trigger.

 

Meso and global models are in decent agreement that the current central Gulf activity will move inland this morning with a break in the action likely this afternoon. Gulf “re-loads” early this evening and models really ping the nearshore and SE counties for sustained heavy to excessive rainfall overnight into Saturday morning. Looks like the best threat would be along and SE of a line from Palacios to Houston to Liberty. This pattern is showing up in several of the meso models so the confidence that excessive rainfall is going to happen is fairly high especially given the copious moisture in place…but the location is slightly different in each model and it is very possible that the heaviest rains remain right along the coast or just offshore.

 

Rainfall Amounts:

Given the saturated and tropical air column in place warm rain production is likely with little evaporation. PWS are over +2SD for late August which is always cause for concern when moist levels reach this high. Galveston picked up over 3.0 inches yesterday in a little over an hour, so this air mass is very much capable of some big short term rainfall rates. Current thinking is that amounts of 2-4 inches will be likely SE of a line from Palacios to Liberty with lesser amounts inland. Could see isolated totals greater than 6 inches near the coast and offshore. Hourly rainfall rates will be on the high side and could easily exceed 3.0 inches.  

 

Caribbean Tropical Wave:

A tropical wave currently located over the central Caribbean Sea is moving westward and will move into the western Caribbean Sea over the weekend. Currently upper level winds are not favorable for development, but are forecast to become more favorable this weekend into early next week. Global model guidance and various ensemble members continue to support tropical cyclone formation in the western Caribbean Sea or southern Gulf of Mexico late this weekend/early next week. Current thinking is that while weak, enough ridging will be present over the US Gulf coast to keep anything that develops moving generally WNW toward the Mexican coastline. Will need to keep a close eye on this feature over the holiday weekend.

 

Tides:  

Still seeing higher than normal tides along the coast…in fact the current high tide this morning has been the highest water level rise yet. This appears to be a function of tidal pile-up over the last few days. Hard pressed to blame the wave action as the buoy 20 E of Galveston is 3.9 ft with 5 second periods this morning. Should start to see tides subside some as winds veer to the SE today, but it will be a slow fall and they will remain elevated through the weekend. Additionally, slightly higher than normal wave action is resulting in high rip-current danger along the middle and upper TX coast.

 

Current Water Levels:

 

Galveston Bay North Jetty: 2.73 ft

Galveston Pier 21: 2.43 ft

Eagle Point: 2.25 ft

Morgan’s Point: 1.86 ft

Lynchburg Ferry Landing: 1.75 ft

Freeport: 2.33 ft

Sargent: 1.34 ft

Rollover Pass: 1.84 ft

Sabine Pass: 2.51 ft

 

[Srain]

From Nesdis:

 

SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 08/30/14 1331Z
SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-683-1404
LATEST DATA USED: GOES-13 1315Z KUSSELSON
NOAA AMSU:1055Z NASA TRMM:1046Z
.
LOCATION...MISSISSIPPI...LOUISIANA...E TEXAS...
.
ATTN WFOS...JAN...LIX...LCH...SHV...
ATTN RFCS...LMRFC...WGRFC...
.
EVENT...VERY HIGH MOISTURE AND CONSOLIDATION OF THAT MOISTURE WITH
DEEP MOISTURE ADVECTION WITH IMPULSE LIFTING NORTH IN WESTERN GULF OF
MEXICO FOR INCREASED AND EXPANSION OF CONVECTIVE COLD CLOUD TOPS/HVY
RAIN CENTERED ON SW TO C LA...
.
SATELLITE ANALYSIS AND TRENDS...CONVECTION HAS BEEN INCREASING AND
EXPANDING ACROSS THE NW GULF OF MEXICO INTO SW TO CENTRAL LOUISIANA AS
DEEP TROPICAL MOISTURE PLUME HAS FURTHER ORGANIZED MORE S TO NORTH IN
THE WESTERN GULF OF MEXICO IN RESPONSE TO SLIGHTLY SHARPER TROUGH COMING
IN FROM THE WEST ACROSS CENTRAL TEXAS AS PER GOES WATER VAPOR LOOP.
MOISTURE PLUME THAT FEATURES VALUES CLOSE TO 2.8" IN THE EXT WESTERN GULF
AND INTO SW LOUISIANA ARE EXTRAORDINARY FOR ANY TIME OF THE YEAR AND WERE
CLOSE TO 3 STANDARD DEVIATIONS ABOVE CLIMO FOR LATE AUGUST AND WERE THAT
HIGH BECAUSE OF SOME MID/HIGH LEVEL MOISTURE THAT GOT PINCHED OFF FROM
THE REMAINS OF PACIFIC TROPICAL SYSTEM MARIE A COUPLE OF DAYS AGO AND
HAS NOW SETTLED IN THE WEST GULF MOISTURE PLUME.  IN THE BIG PICTURE TO
THE EAST..CAN SEE A  SIGNIFICANT DRYING/LOWER OF PWATS MIGRATING WEST THE
PAST 24HRS FROM THE SOUTHERN BAHAMAS/S FL/KEYS INTO THE EASTERN GULF OF
MEXICO THAT HAS ALSO HELPED ORIENT WESTERN GULF PLUME OF MOISTURE MORE
SOUTH-NORTH AND THUS TAKING ADVANTAGE OF THE MORE SOUTHERLY LOW LEVEL
FLOW TO MORE EFFICIENTLY PRODUCE HEAVY RAINFALL ALONG THE TEXAS COAST
NEAR CORPUS CHRISTY AND FURTHER NORTH/NE INTO LOUISIANA.
.
AN ANNOTATED SATELLITE GRAPHIC SHOWING THE HEAVY PRECIPITATION
THREAT AREA SHOULD BE AVAILABLE ON THE INTERNET ADDRESS LISTED
BELOW IN APPROXIMATELY 10-15 MINUTES.
.
SHORT TERM OUTLOOK VALID 1330-1800Z...MEDIUM CONFIDENCE FACTOR
IN SHORT TERM OUTLOOK...DEEP MOISTURE IN PLACE AND CONTINUING TO
CONCENTRATE FROM COAST LOWER TO MIDDLE TEXAS  TO SW AND CENTRAL LA AND
SHOUDL CONTINUE TO EXPAND NORTH AND NE  TOWARD N LA AND MISSISSIPPI
AS CENTRAL TEXAS TROUGH SLUGGISHLY DRIFTS EAST.  WITH SUCH HIGH PRECIP
WATER VALUES AND MOISTURE ADVECTION...MAX HRLY RATES CAN REACH 1-2 INCHES
PER HR, ISOLATED 3"/HR WITH CERTAINLY LOT MORE ACCUMULATED OVER A 2-6HR
PERIOD GIVEN THE NATURE OF CONTINUED EXPANSION OF CONVECTION WITH WEAK
IMPULSES LIFTING NORTH IN SOUTHERLY FLOW AND HIGH MOISTURE CONTINUING
TO FLOW INTO THE AREA TO REPLACE WHAT HAS ALREADY FALLEN.
 

[Srain]

Update from Jeff regarding 99L:

 

Tropical wave that has been tracked for the last several days is moving into the extreme southern Gulf of Mexico this morning.

 

Visible satellite images along with surface observations indicate that a broad area of low pressure has developed along the tropical wave axis over the extreme SE Gulf of Mexico. Deep convection is currently limited to areas to the east and southeast of the broad circulation or over the land areas of the Yucatan peninsula.

 

The National Hurricane Center currently gives the system a 70% chance of development over the next 5 days.

 

Track:

Large scale but weak ridging is building along the US Gulf coast and this should be just enough to keep any tropical system moving WNW or NW toward eastern MX south of the TX coast. This is in agreement with most of the model guidance favoring a track toward the Tampico, MX area.

 

Intensity:

Global models are not very supportive of this system and show only modest development prior to landfall over mainland MX. The circulation appears fairly large on satellite images this morning suggesting it will take time to consolidate and based on the current and expected forward motion there is only about 48 hours of time over water prior to landfall in Mexico. While upper level conditions are favorable with weak shear aloft…it appears the system will run out of time to gather much more strength than a weak tropical storm before landfall.

 

TX Impacts:

Deep tropical moisture is clearly seen moving NW over the central Gulf of Mexico on the north side of the circulation and this will arrive on the TX coast Tuesday into Wednesday. Expect an increase in waves of showers and thunderstorms both days as the moisture flows inland. Rainfall amounts of 1-2 inches are possible with isolated higher amounts in any training bands.

 

ESE fetch will be increasing and helping to build Gulf of Mexico swells as the tropical system deepens over the SW Gulf of Mexico. This will support an increase in wave action and tides along the entire TX coast by mid week. Currently not looking at any water levels much higher than last week on the upper TX coast.

 

[Srain]

Flash Flood potential increasing across Southern Arizona, Northern Mexico, New Mexico and the Texas/Oklahoma Panhandles during the next 72 hours. A combination of deep tropical moisture associated with Dolly remnants and Hurricane Norbert and a WSW flow aloft combining with a weak frontal boundary suggest at least a Slight Risk for Excessive Rainfall may persist for the next 3 days. New Mexico has be rather wet this monsoon season and with slow moving storms capable of producing 1-2 inches per hour, flash flooding is possible across the Southern Colorado River Basin into the Rio Grande River Basin in New Mexico.

 

 

 

 

 

 

 

 

[Srain]

The weekend may offer a chance of seeing some unsettled weather. That cool front does not appear to have much in the way of upper level support or trajectory to bring the chilly air expected in the Northern Plains very far S into Texas. The main upper level energy looks to track across the Northern Plains into the Great Lakes and on E. A front will approach Texas on Thursday and may fire off storms to our N. A secondary piece of upper level energy (short wave) appears to cross the Plains on Friday and that may push the front a bit further S into S Central Texas and perhaps near or just S of the I-10 Corridor. This will not be a 'blue norther' for Texas, so don't expect much of a cool down. Like last weekend when we had a weak boundary draped across the area and torrential rains developed for some last Sunday, a somewhat similar situation may develop as the front serves as focal point for showers/storms to develop. The main issue I see is potential cloudiness as a weak upglide or over running light showers develop inland instead of daytime heating and convective temperature driven storm development along the sea/bay breezes.

 

The next issue is what becomes of potential Tropical system Odile expected to develop just offshore of the Pacific Coast of Mexico and move NW and possibly turning N across the Baja Peninsula early next week. As witnessed early yesterday across Arizona and Nevada, EPAC tropical systems and their moisture (Post Tropical Cyclone Norbert) can lead to flash flooding particularly in the Desert SW. The Phoenix area received about half a years’ worth of annual rainfall Sunday night into yesterday afternoon which is about 7 inches. The fly in the ointment for our Region is some of the models are suggesting deep tropical moisture from the Pacific move ENE across Northern Mexico and into Texas next week. Add to the mix unsettled weather developing in the Western Gulf and stalled boundary and you have a recipe for a possible heavy rainfall event. The monsoonal trough is expected to generate areas of general broad areas of low pressure from the Bay of Campeche across the Isthmus of Tehuantepec into the Eastern Pacific near the Coast of Mexico over the next 5-10 days. There are also indications a cckw will near the area next week as well as some tropical enhancement from the MJO. With all that said it does appear that an unsettled pattern may well develop and persist into the end of next week. As always, there is a lot of uncertainty in the forecast and expect changes as we see how things develop over the next several days.

[Srain]

A rather complex and complicated forecast continues to develop over the next week or so. The upper ridge will remain in control today into tomorrow across our Region and then changes lurk as a ‘cool front’ sags S into Texas and likely pulls up stationary across Central Texas tomorrow evening. A secondary surge of ‘cooler air’ associated with an upper air disturbance embedded within the trough across the Central United States will push the frontal boundary further S and eventually stall somewhere along the NE Mexico/Coastal Texas/Louisiana area offshore on Saturday. Showers/storms may accompany the front as high PW’s of 2+ inches pool along and S of the front. This front will likely not clear us out as over running clouds and showers develop behind the front throughout the weekend into next week.

 

To further complicate the weather picture is a surge of tropical moisture originating from the Western Caribbean moving into the Western Gulf as a tropical wave moves W into the Bay of Campeche tomorrow. There are some indications that a weak area of low pressure may form in the SW Gulf tomorrow into Friday as well. To further complicate things, Eastern Pacific Tropical Depression 15E has formed SSW of Acapulco and is drifting NNW. That tropical cyclone is expected to develop into a Category 2 Hurricane as it near the Baja Peninsula Sunday into Monday next week. Deep tropical moisture from that cyclone may spread ENE across Northern Mexico into Texas early next week. Additionally, the cckw that has been mentioned is progressing E across the Pacific toward Mexico and should arrive in the Western Atlantic Basin in the next 7 to 10 days enhancing tropical convection development across the SW Caribbean and the Western Gulf. We can see the convective enhancement occurring across the Eastern Pacific with 3 areas of disturbed weather (TD 15E, 95E, 96E).  The monsoon trough across the SW Caribbean into the Eastern Pacific remains very active and additional tropical development may be an issue as we head into next week both in the Eastern Pacific and the Western Caribbean and the Western Gulf. Stalled fronts in the NW Gulf tend to raise an eyebrow and the warm water of the Western Caribbean and the Western Gulf are virtually untouched this summer other than TS Dolly. Vertical instability is expected into remain favorable in those areas over the next 7-10 days.

 

 

[Srain]

Morning Update From Jeff:

 

Early season cool front and westward moving tropical wave will combine to produce widespread rainfall Friday-Saturday.

 

A cold front currently over N TX will slowly sag southward and into SE TX Friday afternoon. At the same time a strong tropical wave over the SE Gulf of Mexico will move northwest and landfall along the lower TX and N MX coasts this evening spreading deep tropical moisture inland ahead of the frontal boundary. Rain chances will begin to increase this afternoon as upper ridging aloft begins to flatten and break down. Activity today should be tied to the inland movement of the seabreeze front and remain fairly isolated to scattered.

 

Frontal boundary approaches the region Friday with numerous showers and thunderstorms expect from SW TX into E TX as the boundary interacts with the pooling tropical moisture associated with the tropical wave. PWS climb to 2.2-2.3 inches which is nearing +2 SD above normal for early September and storm motions are forecast to slow into the 5-10mph range raising the threat for excessive short term rainfall. Well defined boundary along with some weak upper support point toward a very wet Friday night into Saturday morning with potential for slow moving very heavy rainfall.

 

Rainfall amounts will likely average 1-2 inches Friday night-Saturday with isolated totals over 5 inches possible.

 

Frontal boundary stalls over the area and eventually washes out over the weekend leaving deep tropical moisture in place. Expect periods of showers and thunderstorms to continue Sunday-early next week with PWS remaining near 2.0 inches and NW flow aloft providing ripples of energy aloft to work on a moist SE TX air mass.

 

Temperatures will cool some this weekend mainly due to the clouds and rainfall and not so much any cold air advection. Outbreak of cold air out of Canada into the central plains (high of 50 at Denver tomorrow) will be shunted more eastward than southward.

 

[Srain]

Morning Update from Meteorologist Jeff L (Harris County Flood Control District):

 

Slow moving cold front will bring a round of potentially heavy rainfall to the area this afternoon into early Saturday.

 

Early next week forecast completely dependent on track and possible development of 92L in the Gulf of Mexico.

 

Will focus first on the incoming frontal system and then elaborate some on 92L. Surface boundary located across NCT X this morning and has stalled. Strong secondary short wave trough currently moving through the central plains is producing a band of thunderstorms north of the frontal boundary along the Red River and the lift associated with this short wave will spread southward today and develop additional thunderstorms along the actual frontal boundary by early this afternoon (roughly along a Del Rio to College Station to Lufkin line). At the same time a tropical wave over the western Gulf of Mexico is moving inland along the TX coast this morning with a surge of tropical moisture currently moving over our outer waters (60nm) and spreading toward the coast. Showers and thunderstorms will begin to develop with this surge and spread inland by mid to late morning and then collide with the southward moving boundary and thunderstorms at some point this afternoon or early evening.

 

Meso models suggest this collision of the northward moving activity and the frontal boundary will occur somewhere north of a line from Columbus to Lake Livingston late this afternoon or early this evening. We have seen this pattern a couple times this summer and each of these events have produced some excessive rainfall totals. With moisture streaming inland from the Gulf and PWS rising to near 2.20 inches high short term rainfall rates in the strongest storms appears likely.

 

Will go with widespread rainfall amounts of .5 to 1.5 inches with isolated totals of 3-4 inches possible. The greatest threat for excessive rainfall appears to be north of I-10 and much of this area is showing significant soil moisture deficits at this time so a good bit of rainfall can be handled. Do not expect any severe weather given the warm tropical profiles, but any Friday night outdoor activities (football) could be impacted by lightning.

 

Dry air attempts to move into the area late Saturday into Sunday and this may confine additional weekend rain chances toward the coast. This “drier” period looks short lived however as 92L and additional tropical moisture begins approaching from the E by early next week.  

 

92L:

Radar data from West Palm Beach and Miami indicate that the area of low pressure off the E FL coast has moved inland overnight and is currently located between West Palm Beach and Fort Lauderdale and is moving WSW to SW. Deep convection has been sheared to the south side of this system across the FL Keys and extreme southern FL. No additional development is expected while the system is over FL.

 

92L will enter into the SE Gulf of Mexico on Saturday and continue toward the west under building mid level ridging along the US Gulf coast. Forecast track guidance overnight remain highly uncertain, but two camps appear to be starting to emerge with one camp featuring a weaker system toward the TX coast and the other camp showing a stronger system curving hard to the right over the central US Gulf coast. Both the GFS and ECMWF models show very little development with this system, and while they both agree, I am not sure they are totally correct given the fairly well defined circulation showing on radar this morning.

 

Upper level conditions over the Gulf of Mexico will be marginally conducive for additional development so the system bears close watch over the weekend.

 

Should the southern track begin to look like it is going to verify, significant forecast changes will be required along the NW Gulf coast for early/mid next week especially with marine impacts.

 

 

[DoctorMu]

The AggieDome RIP for 2014.  The skies have opened over CLL as the frontal boundary is firing off strong storms. Significant rain accumulation expected locally. 

 

3.5 in in the past 90 min IMBY

 

 

 

 

[DoctorMu]

training from Somerville to Madisonville.  Round 2 arriving.

[aggiegeog]

60 and wet this morning. I am not expecting to see 70 today.

[wxmx]

Around 4" have fallen in the last 15 hours...I expect at least 2-4" inches more...it's currently raining at around 1-1.5"/h right now.

[DoctorMu]

4.7 in altogether from the storm IMBY

 

 

Sprinklers de-energized to stun.  Kirk out.

[wxmx]

Around 7" here...it finally let it up after 36 hours of continuous rain...we may still accumulate <1" more before all is said and done.

[DoctorMu]

Tuesday could be interesting.  A westward drifting wave in the Gulf merges with moisture streaming from Odile.

[Srain]

Tuesday could be interesting.  A westward drifting wave in the Gulf merges with moisture streaming from Odile.

QPF looks under estimated during the next 5-7 days. Odile remnants and mid/upper moisture and interaction with embedded short wave this week spell an increasing Flood potential across Southern New Mexico/Northern Mexico and Texas most of this week. Remember EPAC Hurricane Rosa (1994) caused extensive flooding across SE Texas. With the delay of the next front until next Monday at the earliest, the wetter euro solution may be more correct. I am a bit intrigued by the 500/700 vort max moving WNW across the Western Gulf this morning in association the the tropical wave (former 92L). Increasing PW's above 2 inches and Odile moisture spell a potentially very wet week ahead.

[Srain]

Afternoon Update from Jeff:

 

Weak front that brought an unseasonably cool weekend with highs in the 60’s and Saturday and 70’s on Sunday is starting to wash out over the coast waters.

 

Weak tropical wave (remains of 92L) area progressing into the coastal waters this afternoon and will move onto the TX coast tonight. Pool of tropical moisture on the east side of this wave axis will move inland on Tuesday replacing the dry weather of the recent weekend. Additionally, weak disturbances in the NW flow aloft and weak upper level support in the form of divergence should help instigate showers and thunderstorms from Tuesday through the rest of the week. Seabreeze looks to be the main player each day with its inland march each afternoon providing the extra needed lift in a moist air mass to get storms going. Models are keying in on Tuesday and Thursday as the wettest days, but really there is little pattern chance or air mass difference for the next several days. Thursday might end up featuring a slightly better rain chance as ejecting disturbances out of powerful hurricane Odile (see below) becomes entrained in the upper level flow. Odile looks to weaken over NW MX late this week and could provide mid and upper level moisture into the SW US and TX during this time period. 

 

Hurricane Odile:
The strongest hurricane to strike Baja California since 1967 made landfall at Cabo San Lucas overnight with sustained winds of 125mph. Damage to the resorts, hotels, and airport is extensive. The reporting station at the airport recorded a sustained wind of 89mph with gust to 116mph and a pressure of 28.32 in before the site failed. 

 

 

 

 

[Srain]

Morning Update from Jeff:

 

Tropical air mass working its way back into the region along with moisture from TS Odile.

 

Various weather making systems will produce an extended period of unsettled wet weather across much of TX this week into the weekend. Surface trough along the TX coast will be moving slowly inland today with deep tropical moisture noted over much of the central and western Gulf of Mexico. Soundings from CRP, BRO, and LCH all recorded PWS above 2.0 inches as tropical moisture from both the Gulf and TS Odile spread across the state. There is no well defined surface focus (front) to organize rainfall with the exception of the surface trough laying along the coast with favorable speed convergence near this feature. Thus rainfall will be mainly daytime heating driven and fall into the usual pattern of coastal nocturnal development in the 200am to 600am period and then spreading inland between 700am and 1000am.

 

TS Odile is currently moving up the Baja of Mexico this morning and has surprisingly maintained a well defined structure even while interacting with mountains upwards of 3000-5000 ft. Odile will be turning NNE and NE crossing the Gulf of California and then into the state of Arizona. A large shield of mid and high level moisture is peeling off Odile and spreading ENE across much of TX along with embedded energy ejecting outward from the decaying tropical system. Disturbances and additional moisture will only help to foster widespread rainfall and heavier rainfall across the state over the next 48-72 hours as Odile weakens. While this is typically a favorable fall flood setup for TX, the lack of a defined surface front  however should negate training organized excessive rainfall.

 

With that said PWS in the 2.0-2.2 inch range for the next several days will support high hourly rainfall rates on the order of 2-3 inches. HPC grids have a fairly widespread 1-2 inch bullseye over the central and SW sections of SE TX on Wednesday as a disturbance aloft interacts with the tropical plume. Rainfall amounts through the end of the week will likely average 1-2 inches with isolated amounts of 5 inches or higher possible.

 

Late in the weekend another cold front will approach from the north and likely pass through the region. Will need to be watching newly formed TS Polo off the MX west coast as this system could become entangled with the trough and front late in the weekend.

 

 

[DoctorMu]

Weird.  Post this morning vaporized - anyway, a flood watch out for SE Texas.  Juicy Gulf air and tongue lashing from Odile will dump a few inches in SE Texas through Sat.  Center of the bulls-eye on Liberty Co

 

 

 

 

[aggiegeog]

Had some thick fog form at my place this morning allowing temps to fall into the 40s.

[wxmx]

some showers today...but there's was one nasty one in the south part of the city which I witnessed...I calculate 4"/h for ~30-40 minutes...mayhem ensued

[wxmx]

I was probably no more than half a mile from here:

https://www.facebook.com/video.php?v=10154690110800427&fref=nf

[Srain]

MCS moving in and update from Jeff:

 

Severe weather ongoing over NE/E TX with potential to spread SSW into SE TX over the next several hours.

 

Well defined bow echo extends from NW Louisiana to near Centerville, TX  and is racing SSE at 35-45mph. Leading edge of this feature consists of damaging straight line winds to near 70mph with numerous reports of downed trees and power lines. Radar and satellite images show this feature appears to be holding together well as it marches SSE and will soon begin to encounter a much more moist air mass with dewpoints in the 68-72 degree range. Cold pool generation within the backside inflow of the bow feature should also help maintain a strong forward push and help to increase the temperature difference on the leading edge as the downstream air mass heats.

 

SPC has expanded the slight risk area to include most of SE TX for this afternoon as the air mass warms into the mid to upper 80’s instability will rise into the 2000-2500 J/kg range. Main thrust on ongoing bow echo and corridor of wind damage should be from roughly Lake Livingston to Lake Charles however westward development on a surging outflow boundary to the SSW/SW is expected to affect a good part of the region by midday/early afternoon as suggested by HRRR and TX TECH high resolution models.

 

Main threat will be wind damage to 70mph with fast forward storm motions.  

 

 

 

[Quixotic1]

Was on a long trip last night and for lack of anything better to do, I reread our posts over the winter. Man I am hoping we all get a good one. Not as hopeful as I was but am still pretty geeked.

Earliest measurable snowfall in DFW area: October 28th.