February: Calm Weather To End The Month

[wxman57]

We are looking at a very nasty Saturday here in the New Orleans area. Parades will be cancelled, etc. Glad to see you guys in Tx are finally getting some drought relief!

By the way, is cold air still forecast to come down to the Gulf coast at the end of the month?? Just curious. thanks.

Depends on what you call cold. There's a chance of a late-February light freeze down to southeast TX and south LA, but that's in no way certain. Then winter ends...

[redneckweather]

Tonight into Friday morning now? I thought the big rain maker was Friday evening into Saturday morning? Two different systems?

[harpman]

We are looking at a very nasty Saturday here in the New Orleans area. Parades will be cancelled, etc. Glad to see you guys in Tx are finally getting some drought relief!

By the way, is cold air still forecast to come down to the Gulf coast at the end of the month?? Just curious. thanks.

Depends on what you call cold. There's a chance of a late-February light freeze down to southeast TX and south LA, but that's in no way certain. Then winter ends...

LOL! The winter is officially over so says wxman57! LOL!

[MontgomeryCoWx]

same system, just extended.... DROUGHT BUSTERS!

[srainhoutx]

Tonight into Friday morning now? I thought the big rain maker was Friday evening into Saturday morning? Two different systems?

Yes sir. I suspect the Flash Flood Watch will be extended tomorrow for Friday night into Saturday as more data becomes available.
As an interesting tidbit, the last time HGX issued a Flash Flood Watch prior to a potential flooding event was for TS Hermine back in September 2010.

[wxman57]

Tonight into Friday morning now? I thought the big rain maker was Friday evening into Saturday morning? Two different systems?

Yes, two separate systems. One tomorrow morning and one late Friday/Saturday morning. Maybe the rain at my house will top last year's total rainfall of 21" by the end of February. That may mean another new weed for my lawn - duckweed.

[Ptarmigan]

I would not be surprised if it starts raining as early as this late afternoon or evening to tonight. Frankly, we could have thunder while we sleep tonight and on early Saturday morning. I think some areas may see up to 10 inches of rain once it is all over. Not being bullish.

[MontgomeryCoWx]

YES, the one downfall to all of the rain is the horrible weeds

[Ptarmigan]

YES, the one downfall to all of the rain is the horrible weeds

Everything got their downfalls.

[srainhoutx]

FLOOD WATCH
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
321 PM CST THU FEB 16 2012

TXZ163-164-176>179-195>200-210>214-226-227-235>238-171200-
/O.NEW.KHGX.FA.A.0001.120217T0800Z-120217T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-
WHARTON-
INCLUDING THE CITIES OF...ALVIN...ANAHUAC...ANGLETON...BAY CITY...
BELLVILLE...BRENHAM...BROOKSHIRE...BRYAN...CALDWELL...CLEVELAND...
COLDSPRING...COLLEGE STATION...COLUMBUS...CONROE...CORRIGAN...
CROCKETT...DAYTON...EAGLE LAKE...EDNA...EL CAMPO...FREEPORT...
FRIENDSWOOD...GALVESTON...GROVETON...HEMPSTEAD...HOUSTON...
HUMBLE...HUNTSVILLE...KATY...LAKE JACKSON...LAKE SOMERVILLE...
LEAGUE CITY...LIBERTY...LIVINGSTON...MADISONVILLE...
MISSOURI CITY...MONT BELVIEU...NAVASOTA...ONALASKA...PALACIOS...
PASADENA...PEARLAND...PIERCE...PRAIRIE VIEW...RICHMOND...
ROSENBERG...SEALY...SHEPHERD...SUGAR LAND...TEXAS CITY...
THE WOODLANDS...TOMBALL...TRINITY...WEIMAR...WHARTON...WILLIS...
WINNIE
321 PM CST THU FEB 16 2012

...FLOOD WATCH IN EFFECT FROM 2 AM CST FRIDAY THROUGH FRIDAY
AFTERNOON...

THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A

* FLOOD WATCH FOR A PORTION OF SOUTHEAST TEXAS...INCLUDING THE
FOLLOWING COUNTIES...AUSTIN...BRAZORIA...BRAZOS...BURLESON...
CHAMBERS...COLORADO...FORT BEND...GALVESTON...GRIMES...
HARRIS...HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA...
MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER...WALLER...
WASHINGTON AND WHARTON.

* FROM 2 AM CST FRIDAY THROUGH FRIDAY AFTERNOON

* AN UPPER LEVEL DISTURBANCE COUPLED WITH AN INCREASE IN MOISTURE
AND FAVORABLE UPPER LEVEL WINDS WILL PRODUCE PERIODS OF RAIN
LATE TONIGHT INTO FRIDAY MORNING. AT THIS TIME 1 TO 2 INCHES OF
RAIN IS EXPECTED BY NOON FRIDAY. THERE WILL BE POCKETS OF
HEAVIER RAIN AND SOME ISOLATED TOTALS BETWEEN 2 AND 3 INCHES
WILL BE POSSIBLE.

* HEAVY RAIN EARLIER THIS WEEK HAS LEFT SOILS SATURATED. FLOODING
OCCURRED EARLIER IN THE WEEK IN GRIMES AND WALKER COUNTIES WITH
1 TO 3 INCHES OF RAIN. ANY ADDITIONAL RAIN WILL EXACERBATE AN
ALREADY DANGEROUS SITUATION. ANOTHER WEATHER SYSTEM WILL
APPROACH THE REGION LATE FRIDAY NIGHT AND SATURDAY AND COULD
BRING ADDITIONAL HEAVY RAIN TO SOUTHEAST TEXAS. THE FLOOD WATCH
WILL LIKELY BE EXTENDED THROUGH SATURDAY.

[MontgomeryCoWx]

This one is setting up to be quite the event... much like January 9th.

[txflagwaver]

This one is setting up to be quite the event... much like January 9th.

Sadly, the signs aren't great for severe... 18Z GFS mid-level instability isn't bad, mid 50s, but I'd like more shear in the fat part of the CAPE curve. Silver lining, a lot of helicity, which probably is wasted, but maybe the low tracks a smidge farther inland.

Hopefully if there is any severe weather it only makes it to your house..I want no part of it thank you

[ticka1]

Anyone have a clue when the rain will start onshore? Waiting to see if this does happen!

[sambucol]

Anyone have a clue when the rain will start onshore? Waiting to see if this does happen!

^what Ticka said!

[redneckweather]

I don't think that stuff offshore will be moving onshore. We need to look to the west and southwest for development after midnight where currently scattered convection is popping up. I'm fixing to hit the hay so thunder is going to have to wake me up.

[ticka1]

Perhaps the rain is holding off or did not develop?

[srainhoutx]

Showers with embedded storms appear to be passing N of the Houston Metro and the Flood Watch has been reconfigured time wise to begin at noon today. A Flash Flood Watch has been issued for Central Texas for the Hill Country or the Balcones Escarpment on S and E. The boundary lies to our S along Matagorda Bay and on out into the Gulf about 100 or so miles. Light rain showers are possible during the day with increasing areal coverage over night tonight. As the placement of exactly where the heavier rainfall is extremely difficult to forecast, like when we saw guidance suggest rains this morning would be across the area and Flood Watches were hoisted beginning at 2:00 AM, things don't always go as what the models show. It does appear that areas along and N of HWY 59 corridor will have the 'best chance' for heavier training rainfall, but caution is advised as we just don't know where the 'favored areas' will actually be at this time. It still appears a Coastal Low will develop near Corpus and track NE up the Coast. The NAM suggests two split areas of showers/storms while the GFS/Euro suggest a solid precip shield across the entire area. We'll just have to monitor radar trends to see exactly how this situation develops and for anyone to think that any one area would be favored over another would be a 'guess' at best. This will likely be meso driven, so forecasting will be extremely challenging. In other words, no one really knows exactly what time and where the heaviest rainfall will occur. Stay Tuned! An interesting and active 24-36 hours is ahead and expect things to go down hill weather wise as the day progresses.

[srainhoutx]

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
647 AM CST FRI FEB 17 2012

TXZ163-164-176>179-195>200-210>214-226-227-235>238-181300-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-
WHARTON-
647 AM CST FRI FEB 17 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT

...FLOOD WATCH IN EFFECT NOON TODAY THROUGH NOON SATURDAY...
RAIN WILL BE DEVELOPING OVER THE AREA TODAY WITH MOISTURE INCREASING
AND AN APPROACHING UPPER LEVEL LOW PRESSURE SYSTEM LEADING TO
AN INCREASING HEAVY RAINFALL THREAT ACROSS SOUTHEAST TEXAS THIS
AFTERNOON AND ESPECIALLY TONIGHT. SCATTERED TO NUMEROUS SHOWERS
WILL COVER THE AREA WHILE CLUSTERS OF THUNDERSTORMS WITH INTENSE
RAINFALL RATES MOVE THROUGH THE REGION TONIGHT SHOULD PRODUCE
LARGE AREAS OF 2 TO 4 INCHES OF RAINFALL EMBEDDED IN WIDESPREAD
AMOUNTS OF ONE INCH. THE GROUND HAS BECOME SATURATED AND FLOODING
OF LOW LYING AND OTHER FLOOD PRONE AREAS IS LIKELY. A FEW OF THE
STORMS COULD ALSO BECOME STRONG. SMALL HAIL AND STRONG WINDS MAY
ACCOMPANY THE STRONGER STORMS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY
THE HEAVY RAINS WILL COME TO END LATE SATURDAY AS A COLD FRONT
SWEEPS OUT MOST OF THE MOISTURE. GUSTY WEST AND NORTHWEST WINDS OF
15 TO 25 MPH OR STRONGER MAY COVER THE AREAS FROM BRENHAM TO KATY
TO FREEPORT AND PALACIOS. HIGH PRESSURE SHOULD BUILD OVER THE AREA
SATURDAY NIGHT RELAXING THE WINDS. OTHERWISE NO HAZARDOUS WEATHER
IS EXPECTED SUNDAY THROUGH THURSDAY.

.SPOTTER INFORMATION STATEMENT...

EMERGENCY MANAGERS AND STORM SPOTTERS SHOULD PREPARE FOR ACTIVATION
THIS AFTERNOON THROUGH MID AFTERNOON SATURDAY.

[niner21]

Seriously, I'm ok if it goes north of me.... Benefit of filling lake Conroe and I don't have to deal with more mud.

[srainhoutx]

Morning e-mail from Jeff:

Flash Flood Watch extended until noon Saturday.

Significant rainfall event likely tonight-Saturday for much of SE TX with flooding possible.

Discussion:
Thus far the models have not handled the overnight short wave very well with almost no rainfall at all along the TX coast. Short wave was modeled too far southward and has ejected out of MX toward NC TX with widespread mainly light to moderate rainfall. Surface frontal boundary currently extends from near South Padre Island to off the coast of Matagorda Bay and then ENE toward southern Louisiana. Air mass over the western Gulf shows dewpoints in the 66-72 degree range with PWS of 1.5-1.6 inches. Thus far the moisture transport northward has been rather unimpressive as PWS over SE TX have only increased to just over 1.0 inch.

This afternoon:
Powerful upper level trough/storm digging SE into northern MX will begin to spread strong upper level lift across much of TX from SW to NE. At the surface, low pressure will develop on the offshore frontal boundary and begin the NE track up the coast. Latest model runs are more northward with this low and this raises the risk of the downstream warm front over the NW Gulf moving further inland. Expect showers to start to develop and expand northward from late morning through the afternoon hours as upglide of moisture over the frontal slope increases

Tonight-midday Saturday:

Widespread heavy rainfall likely with flooding.

By early this evening the surface low along the southern TX coast will be moving NE up the coast and then likely inland around Matagorda Bay after midnight. Warm front will surge northward toward the coast and likely inland to US 59 overnight. Strong lift both at the surface from the warm front and surface low combined with a splitting jet stream structure aloft as the upper trough moves into SW TX points to rapid development of bands of intense thunderstorms. While the meso models are more keen on a couple of bands of excessive rainfall, the global models show more of a larger area of heavy rain…neither is likely correct nor wrong with this kind of set up. Expect numerous thunderstorms to rapidly develop from the coastal bend into SE TX starting late this evening and then continuing overnight into Saturday morning. Feel the warm front will move inland due to the surface low being displaced slightly further north. This really places the counties along US 59 under the gun for the greatest rainfall and strongest storms.

Rainfall/Flooding:
Moisture levels are progged to reach 200% above normal and a look upstream over the western Gulf does show such values out there. Expect the formation of a 30-40kt low level jet by afternoon today to help advect the western Gulf moisture into place by this evening. Factors will be in place tonight into Saturday for a flash flood setup across the region. Air mass will likely become almost tropical like near and south of the warm front overnight with soundings showing a nearly saturated air column…leading to efficient rainfall production in thunderstorms. Thunderstorms will be capable of some very intense short term rainfall rates of 2-3 inches per hour which can get locations in to trouble very quickly. With a slow moving warm front in the region, this will help to focus and possibly train these high rainfall rate thunderstorms along a boundary greatly increasing the flash flood threat near the warm front. Current thinking is that the warm front will move inland along a line from Victoria to Wharton to Katy to Cleveland (near of just north of the US 59 corridor). Widespread rainfall amounts of 1-3 inches is likely with isolated amounts of 3-5 inches possible. Bands of training thunderstorms will quickly deliver excessive rainfall in a very short period of time overwhelming primary drainage systems. Significant street flooding is likely along with rises on area creeks, bayous, and rivers due to the already saturated grounds in place.

Severe Threat:
With the warm front looking more likely to move inland, this does increase the severe weather threat along and south of this boundary and then ahead of the cold front as the surface low moves across the area. While shear is favorable, instability is generally lacking, but there is some lurking out over the western Gulf. Meso models have been hinting at bowing line segments near the cold front across the coastal areas Saturday morning and also a fair amount of development ahead of the main line which could pose a weak tornado threat given the favorable shear profiles that will be in place. SPC does not have SE TX in a slight risk (see graphic below). Feel an upgrade to a slight risk for areas south of US 59 may be needed today. Main severe threat appears to be wind damage and large hail with an isolated tornado threat.

Midday Saturday-Saturday night:
Surface low moves into Louisiana with thunderstorms exiting to the east. Main upper trough will move over our northern counties and may produce a period of wrap around rainfall into late Saturday afternoon or evening north of I-10. Clearing and cooler Sunday as surface high moves into the area behind the cold front.

Extended:
Another storm system approaches the area Monday-Tuesday, but moisture looks limited so likely only a few showers. Another more potent looking system may be on tap for the middle to end of next week as this highly active pattern continues.

Day 1 Severe Weather Outlook: