Remnants of Tropical Storm Odile

[Srain]

Another day of Flash Flooding underway across SE Texas and Metro Houston.

[Srain]

MESOSCALE PRECIPITATION DISCUSSION 0391

NWS WEATHER PREDICTION CENTER COLLEGE PARK MD

705 AM EDT FRI SEP 19 2014

AREAS AFFECTED...SOUTHEAST TX

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

VALID 191104Z - 191604Z

SUMMARY...THUNDERSTORMS WITH HEAVY RAINFALL HAVE DEVELOPED ACROSS

THE REGION SINCE 08Z. CONSIDERING THE AVAILABLE MOISTURE, HOURLY

RAIN RATES UP TO 2.5" ARE POSSIBLE WHICH COULD LEAD TO FLASH

FLOODING.

DISCUSSION...ELEVATED THUNDERSTORM ACTIVITY HAS FORMED OVER A

STATIONARY FRONT DURING THE PAST FEW HOURS JUST INLAND OF THE TX

COAST, NEAR A ZONE OF WEAK SURFACE CONVERGENCE ACROSS INTERIOR

SOUTHEAST TX. ITS DEVELOPMENT IS BEING AIDED BY A JET STREAK

ALOFT AND CAPE VALUES (MIXED AND UNSTABLE) OF 1000-2000 J/KG LIE

NEAR AND SOUTHEAST OF THE BOUNDARY PER THE MOST RECENT SPC

MESOANALYSIS. LOW-LEVEL INFLOW AND 0-6 KM BULK SHEAR IS MINIMAL,

WHICH SHOULD KEEP CONVECTION OF A SINGLE CELL OR PULSE NATURE.

PRECIPITABLE WATER VALUES OVER 2", AROUND THE 90TH PERCENTILE FOR

MID-SEPTEMBER, SUPPORT HOURLY RAIN RATES OF 2.5" WITHIN THIS

ACTIVITY.

MESOSCALE QPF GUIDANCE INDICATES THAT LOCAL AMOUNTS OF 2-4" ARE

POSSIBLE IN THIS REGION, WHICH WOULD LIKELY BE THE RESULT OF CELL

MERGERS. AS CAPE/INSTABILITY BECOMES EXHAUSTED IN THE COLD SECTOR

OF THE BOUNDARY RELATIVELY EASILY, THE THREAT SHOULD BECOME

INCREASINGLY COASTAL WITH TIME. THE 00Z SSEO NEIGHBORHOOD

PROBABILITIES OF EXCEEDING THREE HOURLY FLASH FLOOD GUIDANCE

SUGGEST THAT THE THREAT OF EXCEEDING FLASH FLOOD GUIDANCE IN THE

REGION COULD PERSIST AT LONG AS 19Z ALONG PORTIONS OF THE MIDDLE

AND UPPER TX COAST. SINCE CONVECTION IS OF THE PULSE VARIETY,

BELIEVE THE THREAT COULD BE OF SHORTER DURATION, SO USED A FIVE

HOUR WINDOW FOR THIS MPD. THE REGION HAS BEEN SATURATED BY

RAINFALL OVER THE PAST COUPLE DAYS, MAKING IT MORE SUSCEPTIBLE TO

FLASH FLOODING. FLASH FLOODING IS CONSIDERED POSSIBLE HERE.

ROTH

[Srain]

From Nesdis:

 

SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 09/19/14 1302Z
SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-683-1404
LATEST DATA USED: GOES-13 1245Z    WARREN
.
LOCATION...W TEXAS...SE NEW MEXICO...
.
ATTN WFOS...SJT...LUB...MAF...ABQ...EPZ...
ATTN RFCS...WGRFC...
.
EVENT...HEAVY RAINS SHIFTING S AND E ASSOCIATED WITH REMNANTS OF ODILE
.
SATELLITE ANALYSIS AND TRENDS...LATEST SATELLITE AND 12Z RAOB ANALYSIS
INDICATES MID-LEVEL CIRCULATION FROM THE REMNANTS OF ODILE IS CENTERED
OVER SERN NM NEAR THE TX BORDER INVOF ROW.  12Z MESOANALYSIS ALSO SHOWS A
SFC AREA OF LOW PRESSURE JUST W OF CNM WITH A WELL DEFINED W TO E ORIENTED
MOISTURE/CONVERGENCE BOUNDARY FROM JUST S OF GDP EXTENDING E TO MAF.
BLENDED TPW AND GPS NETWORK SHOW ANOMALOUS MOISTURE ACROSS THE REGION
WITH PW VALUES NEAR 2.0" (125-175% ABOVE CLIMO).  EXPERIMENTAL LAYERED PW
PRODUCT FROM CIRA/NASA SPORT INDICATES AN ADDITIONAL MOISTURE CONNECTION
TO TROPICAL STORM POLO (LOCATION IN THE E PACIFIC) HAS BEEN ADVECTING NE
INTO SW TX AT THE 500 TO 300-MB LAYER FOR SEVERAL HRS NOW.  THIS MATCHES
WELL WITH MID/UL SATELLITE WINDS AND INCREASED MID-LVL MOISTURE SIGNAL
IN RECENT WATER VAPOR ALONG THE SRN EDGE OF THE REMNANT LOW OF ODILE.
.
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 1300-1700Z...MEDIUM CONFIDENCE FACTOR
IN SHORT TERM OUTLOOK...BATCH OF SHOWERS/TSTMS ACTIVITY IS EXPECTED
TO CONTINUE SHIFTING ESE OVER THE NEXT 3-5 HRS ALONG FAVORABLE LLVL
CONVERGENCE AXIS. HAVE NOTICED 850-MB FLOW ACROSS W TX GRADUALLY
VEERING OVER THE PAST 1-2 HRS WHICH SHOULD HELP SUPPORT ACTIVITY
EXPANDING/SHIFTING ESE.  A SUBTLE SHORTWAVE IMPULSE CURRENTLY TRACKING E
ACROSS W TX MAY ALSO HELP TRIGGER/EXPAND SCATTERED ELEVATED SHOWERS/TSTMS
FARTHER E INVOF SNK AND SWW.  ANTICIPATING AXIS OF HEAVIEST RAINFALL SETUP
FROM GDP TO JUST NW OF SJT THRU 17Z.  WEAK CLOUD BEARING WRLY FLOW AND
DEEP SATURATED LAYER AS NOTED IN 12Z RAOBS ACROSS REGION SHOULD SUPPORT
THREAT OF CELL TRAINING LEADING TO ENHANCED RAINFALL AMOUNTS ALONG  THIS
ANTICIPATED HEAVY RAINFALL AXIS.
 

[LocoAko]

TEN INCHES OF RAIN in 4 hours (doubling their yearly total) this morning at Gail mesonet. 10.79 inches since midnight under the core of remnant ODILE. A very rare event for West Texas......

[Srain]

Rather amazing to see the remnant moisture of Odile in the mid levels as well as TS Polo just to the W of Cabo San Lucas trapped in a stagnant flow around a upper ridge anchored across Mexico today. While Oklahoma and most of Arizona missed out on the severe flooding, portions of Southern New Mexico, W/Central and SE Texas as well as Mexico have been very hard hit with rainfall totals near or above the 10 inch mark for the event.

 

[Chinook]

3 day total from Midland/Odessa radar. The red dot is a spot of 17.4" of rain in 3 days. Gail, TX is in the northeast corner of this plot.

 

 

 

 

 

 

 

 

[wxmx]

Favorable anticyclonic flow aloft in a very moist environment, plus some orographic lifting in the wettest month of the year, usually spells a rainy period. After some brief showers the past two days, it's currently raining cats and dogs (~1.5"/h) under very weak radar echoes from the distant BRO radar with stronger echoes approaching from the east. My guess is that it will become more than a nuisance in the morning. We'll see.

[wxmx]

Ha! Like a prophecy. My morning commute became a 1:40 hour ride thru all kinds of streams/ponds (normal is 40 minutes). Around 4 inches have fallen, and there's still more to come for a few days. This plus the earlier event this month will bring the September total to more than 50% of our average annual rainfall.

[LocoAko]

Gail, TX is up to 18.24" of rain for the month, with 15.31" of that falling since the 16th.

http://www.mesonet.ttu.edu/Sep14rain.htm