April 2015: Pleasant Weather To End April

[srainhoutx]

Morning briefing from Jeff:

Very active weather period on tap for the region.

Severe Thunderstorms and flooding rainfall possible today-Saturday.

Large slow moving upper level storm system has moved into the SW US with the upper level jet stream becoming aligned over SE TX from SW to NE. At the surface a weak warm front is found over the nearshore waters and will be pushing inland today. Morning soundings from BRO and CRP showed impressive PWS values of 1.99 (BRO) and 1.66 (CRP) and SPC mesoanalysis shows and extensive area of tropical moisture from S TX across the western Gulf of Mexico shifting northward. Skies are broken across SE TX allowing some marginal surface heating to occur while water vapor images show an upstream disturbance over MX approaching the Rio Grande River. Air mass over SC TX is already unstable with most unstable CAPE of 2338 J/kg and forecasted values of over 3000 J/kg at CRP this afternoon. 0-6km shear values are near 40kts which will lead to storm organization and potentially some supercell structures.

Inland moving warm front coupled with approaching disturbance will result in a rapid increase in strong to severe thunderstorms early this afternoon across the region. Extremely heavy rainfall of 2-3 inches per hour along with large hail and damaging winds will be possible. Cannot rule out an isolated tornado near the coastal counties where low level shear values are the highest and we may see some enhancement near the inland moving warm front.

Friday:

Much more significant weather day appears likely on Friday with the potential for round 2 to really impact the region.

Factors appear to be coming together for a fairly widespread severe weather threat on Friday as a very strong upper level disturbance ejects out of MX during peak heating forming a large forward propagating MCS/bow echo. Downstream air mass over SE TX becomes very unstable Friday afternoon with lift increasing. SPC forecasters are concerned that a large MCS with significant bowing/wind damage threat may develop in the late afternoon and evening hours from SC TX into SE TX. High resolution models are suggesting a severe MCS will affect the region with potential for widespread wind damage. While low level inflow looks marginal the unstable air mass and likely strong downdraft potential may result in wind damage along the leading gust front. A few very strong gusts (+70mph) will be possible.

Flood Threat:
Upstream air mass over S TX and the western Gulf is extremely moist with PWS approaching 2.0 inches which is near climo maximums for mid April. This will support excessive rainfall rates across the region under the strongest storms. Starting to get a little worried about the potential for HP supercell formation along the warm frontal boundary as these cells tend to move slower than the background shallower cells and can be prodigious short term rainfall producers. Grounds are already wet from well above normal rainfall of late and heavy rainfall will only generate additional run-off. Flash flooding within urban areas will certainly be possible under the heavy rainfall cores along with rises on area watersheds.

Weekend:
Additional storms will be possible Saturday and possibly Sunday. Main focus right now is today and especially Friday.

[unome]

rec'd an email from Alert Houston, great service, easy to sign up & no spam http://www.houstonemergency.org/go/doc/ ... in-Houston

http://www.houstonemergency.org/go/doc/2263/2492274/

AlertHouston | Heavy Rain, Street Flooding Possible Today and Friday

The City of Houston is monitoring the potential for heavy rain which may impact the greater Houston area today. Heavy rain may cause street flooding in low-lying areas, especially along freeway access roads.
In addition, these storms may bring sizable hail and strong winds
Actions to Take
Residents are asked to avoid creeks, bayous and low-lying areas, and plan ahead for the potential for heavy rain today.
Avoid driving through areas of high water.
Stalling your vehicle in high water is not only embarrassing and expensive, it can put your life, and the life of first responders in danger.
Residents should plan additional time for their commutes, and find alternate routes around areas where high water normally occurs.
Get up-to-date rainfall totals, as well as the status of creeks and bayous from the Harris County Flood Control District at harriscountyfws.org .
Please report any areas of high water, flooding or debris/trees on city streets to Houston 311 (311 or 713.837.0311), or on the Houston 311 App for Android or iOS.

[srainhoutx]

Storms developing along the N bound advancing warm front across Ft. Bend and Southern Harris Counties are showing some weak rotation. Watch out for some very gusty winds and heavy rainfall with these storms.

[srainhoutx]

Pea to dime sized hail reported in downtown Floresville (Wilson County in Central Texas).

[srainhoutx]

Getting reports of dime to golf ball size hail near Hedwig Village (I-10 @ West Beltway 8)

[srainhoutx]

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1226 PM CDT THU APR 16 2015

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
NORTH CENTRAL HARRIS COUNTY IN SOUTHEASTERN TEXAS...
SOUTH CENTRAL MONTGOMERY COUNTY IN SOUTHEASTERN TEXAS...

* UNTIL 100 PM CDT

* AT 1226 PM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
CAPABLE OF PRODUCING QUARTER SIZE HAIL. THIS STORM WAS LOCATED OVER
CARVERDALE...OR OVER JERSEY VILLAGE...AND MOVING NORTH AT 25 MPH.

* LOCATIONS IMPACTED INCLUDE...
TOMBALL...JERSEY VILLAGE...SPRING VALLEY...SPRING...SPRING BRANCH
WEST...GREATER GREENSPOINT...SPRING BRANCH NORTH...ADDICKS PARK
TEN...THE WOODLANDS...NORTHWESTERN MEMORIAL PARK...HILSHIRE
VILLAGE...WILLOWBROOK...ACRES HOME...FAIRBANKS / NORTHWEST
CROSSING...GREATER INWOOD...WESTBRANCH...HIDDEN VALLEY...SPRING
BRANCH CENTRAL...SPRING BRANCH EAST AND SPLASHTOWN.

[srainhoutx]

Numerous reports now coming in of 1 inch hail near Hedwig Village. This cell is slowly lifting N. Folks in Jersey Village/Copperfield/Cypress and Montgomery County heads up.

[michmich]

Had 1/2"-1" hail here at Gessner and Hempstead.

Now the sun's out.

[srainhoutx]

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1237 PM CDT THU APR 16 2015

HARRIS TX-LIBERTY TX-CHAMBERS TX-MONTGOMERY TX-
1237 PM CDT THU APR 16 2015

...SIGNIFICANT WEATHER ADVISORY FOR LIBERTY...NORTHEASTERN HARRIS...
SOUTHEASTERN MONTGOMERY AND NORTHERN CHAMBERS COUNTIES UNTIL 115 PM
CDT...

AT 1237 PM CDT...DOPPLER RADAR WAS TRACKING A LINE OF STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM NEAR CROSBY TO WINNIE...AND
MOVING NORTHEAST AT 20 MPH.

DIME SIZE HAIL AND WINDS IN EXCESS OF 30 MPH WILL BE POSSIBLE WITH
THESE STORMS.

LOCATIONS IMPACTED INCLUDE...
NORTHEASTERN BAYTOWN...LIBERTY...CLEVELAND...DAYTON...BARRETT...
KINGWOOD...CROSBY...MONT BELVIEU...ANAHUAC...OLD RIVER-WINFREE...
AMES...DAISETTA...HARDIN...PLUM GROVE...KENEFICK...COVE...DEVERS...
DAYTON LAKES...WINNIE AND STOWELL.

[srainhoutx]

FLOOD ADVISORY
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1245 PM CDT THU APR 16 2015


LIBERTY TX-HARRIS TX-CHAMBERS TX-
1245 PM CDT THU APR 16 2015

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* FLOOD ADVISORY FOR...
SOUTHEASTERN LIBERTY COUNTY IN SOUTHEASTERN TEXAS...
EAST CENTRAL HARRIS COUNTY IN SOUTHEASTERN TEXAS...
CHAMBERS COUNTY IN SOUTHEASTERN TEXAS...

* UNTIL 145 PM CDT

* AT 1243 PM CDT...DOPPLER RADAR INDICATED HEAVY RAIN DUE TO
THUNDERSTORMS. THIS WILL CAUSE MINOR FLOODING IN THE ADVISORY AREA.
UP TO TWO INCHES OF RAIN HAVE ALREADY FALLEN.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
NORTHEASTERN BAYTOWN...BEACH CITY...MONT BELVIEU...ANAHUAC...OLD
RIVER-WINFREE...COVE...WINNIE...STOWELL...HANKAMER AND WALLISVILLE.

[srainhoutx]

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1248 PM CDT THU APR 16 2015

HARRIS TX-MONTGOMERY TX-
1248 PM CDT THU APR 16 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 100 PM CDT
FOR NORTH CENTRAL HARRIS AND SOUTH CENTRAL MONTGOMERY COUNTIES...

AT 1248 PM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
CAPABLE OF PRODUCING QUARTER SIZE HAIL. THIS STORM WAS LOCATED NEAR
SPLASHTOWN...OR NEAR GREATER GREENSPOINT...MOVING NORTHEAST AT 30
MPH. THIS STORM HAS A HISTORY OF PRODUCING GOFL BALL TO ONE INCH
SIZE HAIL.

LOCATIONS IMPACTED INCLUDE...
TOMBALL...SPRING...GREATER GREENSPOINT...THE WOODLANDS...HIDDEN
VALLEY...SPLASHTOWN...WILLOWBROOK...HOOKS AIRPORT...GREATER INWOOD
AND NORTHERN ACRES HOME.

[srainhoutx]

Storms increasing in areal coverage across W and S Central Texas ahead of a shortwave upper air disturbance moving out of Mexico and along the warm front just N of Corpus Christi.

[srainhoutx]

Severe Storms are developing in far SE Texas and SW Louisiana.

[srainhoutx]

Code: Select all

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
103 PM CDT THU APR 16 2015

...RAINFALL REPORTS OF OVER 0.20 INCHES IN THE PAST THREE HOURS...

LOCATION                     AMOUNT    TIME/DATE       LAT/LON              

...CHAMBERS COUNTY...
SPINDLETOP BAYOU @ STATE HIG 1.06 IN   1243 PM 04/16   29.75N/94.38W        
9 SSW STOWELL                0.24 IN   1212 PM 04/16   29.67N/94.44W        
3 SSW MONT BELVIEU           0.20 IN   1245 PM 04/16   29.80N/94.90W        

...FORT BEND COUNTY...
PARK STREET                  0.56 IN   1224 PM 04/16   29.63N/95.64W        
SUGARLAND                    0.52 IN   1227 PM 04/16   29.64N/95.65W        
ELDRIDGE                     0.48 IN   1225 PM 04/16   29.63N/95.62W        
SUGARLAND                    0.44 IN   1226 PM 04/16   29.61N/95.64W        
GREATWOOD                    0.40 IN   1215 PM 04/16   29.58N/95.68W        
FLOUR                        0.36 IN   1221 PM 04/16   29.61N/95.63W        
1 W STAFFORD                 0.34 IN   1243 PM 04/16   29.62N/95.59W        
STAFFORD                     0.33 IN   1245 PM 04/16   29.61N/95.56W        
1 ENE STAFFORD               0.32 IN   1248 PM 04/16   29.63N/95.54W        

...HARRIS COUNTY...
LITTLE VINCE BAYOU AT JACKSO 0.76 IN   1159 AM 04/16   29.71N/95.20W        
2 SSW CLOVERLEAF             0.69 IN   1240 PM 04/16   29.75N/95.19W        
SAN JACINTO RIVER NEAR RIO V 0.52 IN   1228 PM 04/16   29.88N/95.08W        
IH-10 @ NORMANDY             0.48 IN   1215 PM 04/16   29.77N/95.21W        
BRAYS BAYOU @ STATE HWY 6    0.32 IN   1229 PM 04/16   29.72N/95.64W        
GALVESTON ROAD @ ALLENDALE   0.24 IN   1158 AM 04/16   29.68N/95.25W        
KEEGANS BAYOU KEEGAN RD      0.24 IN   1158 AM 04/16   29.67N/95.60W        
3 WNW CROSBY                 0.23 IN   1247 PM 04/16   29.95N/95.11W        
LAKE HOUSTON                 0.23 IN   1230 PM 04/16   29.91N/95.14W        
BUFFALO BAYOU W BELT DRIVE   0.22 IN   1230 PM 04/16   29.76N/95.56W        
CARPENTERS BAYOU AT I 10     0.20 IN   1225 PM 04/16   29.77N/95.14W        
3 W BELLAIRE                 0.20 IN   1236 PM 04/16   29.69N/95.52W        

OBSERVATIONS ARE COLLECTED FROM A VARIETY OF SOURCES WITH VARYING
EQUIPMENT AND EXPOSURE. NOT ALL DATA LISTED ARE CONSIDERED OFFICIAL.

$$

NWS HOUSTON/GALVESTON TX

[srainhoutx]

Storms developing N and E of Corpus Christi need to be watched as they consolidate and move NE toward Victoria. These storms may affect Metro Houston during the afternoon rush hour.

[unome]

hail damage to cars in Gessner/290 area

[srainhoutx]

MESOSCALE DISCUSSION 0311
NWS STORM PREDICTION CENTER NORMAN OK
0134 PM CDT THU APR 16 2015

AREAS AFFECTED...PORTIONS OF CENTRAL/SRN TX

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 161834Z - 162030Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...THUNDERSTORMS ARE EXPECTED TO INCREASE IN AREAL COVERAGE
AND INTENSITY THIS AFTERNOON...AND THE STRONGEST STORMS WILL POSE A
RISK FOR LARGE HAIL AND DAMAGING WIND GUSTS. TRENDS IN
COVERAGE/INTENSITY ARE BEING MONITORED AND A WATCH IS POSSIBLE BY
20Z.

DISCUSSION...TSTMS HAVE EXPANDED IN AREAL COVERAGE OVER PORTIONS OF
CENTRAL/SRN TX SINCE 17Z...AND WERE LOCATED WITHIN A MOIST/UNSTABLE
AND GENERALLY UNCAPPED ENVIRONMENT. LARGE-SCALE FORCING ASSOCIATED
WITH THE LEFT EXIT REGION OF A SOUTHWEST-NORTHEAST ORIENTED JET
MAXIMUM OVER FAR SOUTH TX/NRN MEXICO WAS LIKELY CONTRIBUTING TO THE
UPWARD TREND IN COVERAGE.

TEMPERATURES WILL CONTINUE TO WARM INTO THE LOWER/MID 80S...AND
COMBINED WITH 65-70 DEGREE DEW POINTS AND STEEP MID-LEVEL LAPSE
RATES WILL RESULT IN MLCAPE BETWEEN 2000 AND 2500 J/KG. DEEP-LAYER
SHEAR WILL BE SUFFICIENT FOR SUPERCELLS WITH A RISK FOR LARGE HAIL
AND DAMAGING WINDS. WHILE LOW-LEVEL FOCUSING MECHANISMS REMAIN
WEAK/NEBULOUS...STORM-SCALE INTERACTIONS IN THE FORM OF MERGING COLD
POOLS/OUTFLOW MAY SERVE TO ENHANCE AREAS OF GREATER SVR THREAT
THROUGH THE AFTN HOURS.

CONVECTIVE TRENDS WILL BE MONITORED AND A WATCH IS POSSIBLE PRIOR TO
20Z

..BUNTING/THOMPSON.. 04/16/2015


ATTN...WFO...HGX...FWD...CRP...EWX...SJT...

[srainhoutx]

From Nesdis:

SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 04/16/15 1849Z
SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-683-1404
LATEST DATA USED: GOES-13 1845Z HEEPS
.
LOCATION...SW MISSISSIPPI...S LOUISIANA...SE TEXAS...
.
ATTN WFOS...JAN...LIX...LCH...SHV...HGX...FWD...CRP...EWX...
ATTN RFCS...LMRFC...WGRFC...
.
EVENT...SATELLITE FEATURES FOR HEAVY RAIN EVENT
.
SATELLITE ANALYSIS AND TRENDS...LATEST WV IMAGERY INDICATES ANOMALOUS
MID-UL LOW ROTATING NEARLY OVER THE FOUR CORNERS REGION. DOWNSTREAM
SPLIT FLOW BWTN POLAR/SUBTROPICAL JET IS SEEN LOCATED OVER SERN TX/SRN LA
PLACING THIS AREA UNDER LARGE-SCALE DIFFLUENCE AND ENHANCED LIFT. MULTIPLE
WEAK S/WV IMPULSES ARE SEEN IN THE SUBTROPICAL STREAM IN WV IMAGERY...ONE
LOCATED ACROSS ERN TX MOVING INTO WRN LA AND ANOTHER FURTHER BACK IN
WRN TX NEAR THE RIO GRANDE. MOISTURE FLUX INTO THE AREA HAS INCREASED PW
VALUES THROUGHOUT DAY TO VALUES NEAR/ABOVE +2 STD DEV ACROSS SERN TX/SRN
LA. GOES SOUNDER ALSO INDICATES INCREASED INSTABILITY THROUGHOUT THE DAY
ACROSS TX WITH CAPE VALUES REACHING 3000-4000 J/KG IN MUCH OF THE STATE.
.
CONVECTIVE RESPONSE HAS BEEN SEEN AS S/WV ENERGY CROSSED EWRD INTO
FAVORABLE MOISTURE/INSTABILITY ENVIRONMENT AS WELL AS CONVECTION
DEVELOPING INVOF COASTAL TROF LOCATED JUST OFF TX/LA COASTLINE AND
EXTENDING INLAND OVER S CENT LA. WHILE CONVECTION HAS FIRED ACROSS THIS
BNDRY...THERE IS NO APPARENT BNDRY LOCATED FURTHER INLAND OVER TX/LA WHICH
WOULD IMPLY MUCH OF THE CONVECTION FURTHER INLAND ESPECIALLY OVER CENT TX
IS ELEVATED IN NATURE. THIS MAKES FINDING A POSSIBLE AREA OF TRAINING/MAX
RAINFALL DIFFICULT. IMAGINE THAT THE BEST POSSIBILITY OF TRAINING WOULD
OCCUR INVOF SPLIT FLOW DOWNSTREAM OF THE ANOMALOUS HEIGHT FALLS...WHICH IS
SEEN IN WV IMAGERY/GOES SATL WINDS IN AN AREA TO THE NW OF IAH EXTENDING
TO THE ENE TO NE OF LCH. BEST INFLOW IS IN SRN/SERN TX WHERE VWP DATA
FROM CRP INDICATES SRLY 35 KT WINDS AT 85H AND 30 KT SWRLY FLOW AT 85H
IS SEEN JUST SOUTH OF IAH. THIS LLJ SHOULD CONTINUE MOISTURE/INSTABILITY
FLUX INTO THE REGION AND AS SUCH INCREASE RAINFALL RATES.

[srainhoutx]

FLOOD ADVISORY
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
150 PM CDT THU APR 16 2015

LIBERTY TX-CHAMBERS TX-
150 PM CDT THU APR 16 2015

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* FLOOD ADVISORY FOR...
SOUTHEASTERN LIBERTY COUNTY IN SOUTHEASTERN TEXAS...
EASTERN CHAMBERS COUNTY IN SOUTHEASTERN TEXAS...

* UNTIL 345 PM CDT

* AT 148 PM CDT...DOPPLER RADAR INDICATED HEAVY RAIN DUE TO
THUNDERSTORMS. THIS WILL CAUSE MINOR FLOODING IN THE ADVISORY AREA.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
DEVERS...STOWELL...WINNIE AND HANKAMER.

[srainhoutx]

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
155 PM CDT THU APR 16 2015

TXZ210-226-235-161945-
JACKSON TX-COLORADO TX-WHARTON TX-
155 PM CDT THU APR 16 2015

...SPECIAL WEATHER STATEMENT...

AT 154 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
INEZ...OR 10 MILES WEST OF EDNA...MOVING NORTHEAST AT 40 MPH.

SMALL HAIL AND WINDS IN EXCESS OF 30 MPH WILL BE POSSIBLE WITH THIS
STORM.

LOCATIONS IMPACTED INCLUDE...
EL CAMPO...EDNA...GANADO...MORALES...CORDELE AND LOUISE.