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Hazardous weather outlook, from the National Weather Service, Norman Forecast Office

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
THU AUG 30 2012

HARPER-WOODS-ALFALFA-GRANT-KAY-ELLIS-WOODWARD-MAJOR-GARFIELD-NOBLE-
ROGER MILLS-DEWEY-CUSTER-BLAINE-KINGFISHER-LOGAN-PAYNE-BECKHAM-
WASHITA-CADDO-CANADIAN-OKLAHOMA-LINCOLN-GRADY-MCCLAIN-CLEVELAND-
POTTAWATOMIE-SEMINOLE-HUGHES-HARMON-GREER-KIOWA-JACKSON-TILLMAN-
COMANCHE-STEPHENS-GARVIN-MURRAY-PONTOTOC-COAL-COTTON-JEFFERSON-
CARTER-JOHNSTON-ATOKA-LOVE-MARSHALL-BRYAN-HARDEMAN-FOARD-WILBARGER-
WICHITA-KNOX-BAYLOR-ARCHER-CLAY-
 THU AUG 30 2012

THIS HAZARDOUS WEATHER OUTLOOK COVERS NORTHERN…WESTERN…
CENTRAL…AND SOUTHERN OKLAHOMA…AND WESTERN NORTH TEXAS.

.DAY ONE…TODAY AND TONIGHT…

THUNDERSTORM OUTLOOK…
THERE IS A SLIGHT CHANCE OF THUNDERSTORMS IN SOUTHEAST
OKLAHOMA THIS AFTERNOON AND IN CENTRAL AND SOUTHEAST OKLAHOMA
TONIGHT.

DISCUSSION…
THERE WILL BE A CHANCE FOR SHOWERS AND THUNDERSTORMS IN SOUTHEAST
OKLAHOMA THIS AFTERNOON AS DEEPER MOISTURE ASSOCIATED WITH THE
CIRCULATION AROUND ISAAC REACHES SOUTHEAST OKLAHOMA. AS THE DEEPER
MOISTURE SPREADS NORTHWARD TONIGHT…SCATTERED SHOWERS AND A FEW
THUNDERSTORMS WILL BE POSSIBLE…MAINLY EAST OF I-35. INSTABILITY
AND SHEAR WILL REMAIN RELATIVELY WEAK AND SEVERE STORMS ARE NOT
EXPECTED.

PROBABILITY TABLE…
VALID THROUGH 700 AM CDT FRIDAY AUG 31.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
              NWS NORMAN COUNTY WARNING AREA…30 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR… 5 PERCENT.

OTHER HAZARDOUS WEATHER…
NONE.

.DAYS TWO THROUGH SEVEN…FRIDAY THROUGH WEDNESDAY…

THUNDERSTORM OUTLOOK…
THUNDERSTORMS WILL BE POSSIBLE ACROSS THE EASTERN HALF OF OKLAHOMA
FRIDAY THROUGH EARLY SATURDAY…AS THE REMNANTS OF ISAAC MOVE
THROUGH EASTERN OKLAHOMA AND WESTERN ARKANSAS. NO SEVERE
THUNDERSTORMS ARE EXPECTED…BUT HEAVY RAINFALL AND BRIEF GUSTY
WINDS WILL BE POSSIBLE WITH ANY OF THE STRONGER SHOWERS OR STORMS
THAT OCCUR.

OTHER HAZARDOUS WEATHER…
NONE.

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Hydrometeorological Prediction Center rainfall forecast regarding Isaac

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A look at radar in the New Orleans area from the National Weather Service

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FYI: Short-term forecast from the National Weather Service, Shreveport, La.

SHORT TERM FORECAST
NATIONAL WEATHER SERVICE SHREVEPORT LA
601 PM CDT WED AUG 29 2012

ANGELINA-BIENVILLE-CALDWELL-CLAIBORNE-DE SOTO-GRANT-JACKSON-LA SALLE-
LINCOLN-NATCHITOCHES-OUACHITA-RED RIVER LA-SABINE LA-SABINE TX-
SAN AUGUSTINE-SHELBY-UNION AR-UNION LA-WINN-
INCLUDING THE CITIES OF…BIENVILLE…CENTER…COLFAX…COLUMBIA…
COUSHATTA…EL DORADO…FARMERVILLE…HEMPHILL…HOMER…JENA…
JONESBORO…LUFKIN…MANSFIELD…MANY…MONROE…NATCHITOCHES…
RUSTON…SAN AUGUSTINE…WINNFIELD
601 PM CDT WED AUG 29 2012

.NOW…
ISOLATED SHOWERS WILL CONTINUE TO SHIFT QUICKLY SOUTHWEST ACROSS
PORTIONS OF NORTHWEST LOUISIANA AND DEEP EAST TEXAS THROUGH EARLY
EVENING. THESE SHOWERS WILL CROSS NORTHERN TOLEDO BEND AND INTO
NORTHERN SABINE AND SAN AUGUSTINE COUNTIES IN DEEP EAST TEXAS DURING
THE NEXT HOUR…POSSIBLY AFFECTING THE CITIES OF GENEVA AND SAN
AUGUSTINE. OTHER BANDS OF SHOWERS ASSOCIATED WITH THE OUTER PERIPHERY
OF TROPICAL STORM ISAAC WILL CONTINUE TO EXPAND SLOWLY WEST AND
AFFECT THE SOUTHEAST SECTIONS OF NORTHCENTRAL LOUISIANA THROUGH THE
EVENING. THESE SHOWERS WILL MAINLY BE SOUTHEAST OF A MANY…
NATCHITOCHES…DODSON AND MONROE LINE DURING THE NEXT COUPLE OF
HOURS. SOME OF THESE SHOWERS WILL PRODUCE BRIEF HEAVY RAINFALL…AS
WELL AS WIND GUSTS TO 40 MPH. THE SHOWERS WILL BECOME MORE WIDESPREAD
LATER TONIGHT ACROSS NORTHCENTRAL LOUISIANA…AS WELL AS FREQUENT
WIND GUSTS OF 30 TO 40 MPH.

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Tropical Storm Isaac information from the National Hurricane Center

TROPICAL STORM ISAAC DISCUSSION NUMBER  35
NWS NATIONAL HURRICANE CENTER MIAMI FL      

 400 PM CDT WED AUG 29 2012

ISAAC CONTINUES TO TRUDGE SLOWLY TO THE NORTHWEST ACROSS
SOUTHEASTERN LOUISIANA…AND THE INITIAL MOTION REMAINS  310/5
KT…BASED ON DOPPLER RADAR DATA FROM SLIDELL AND FT. POLK
LOUISIANA. THE MODEL GUIDANCE HAS COME INTO BETTER AGREEMENT WITH
THE PREVIOUS OFFICIAL TRACK…SO NO SIGNIFICANT CHANGES WERE MADE
FOR THIS ADVISORY. ISAAC SHOULD CONTINUE TO MOVE NORTHWESTWARD AND
EVENTALLY NORTHWARD THROUGH A WEAKNESS IN THE SUBTROPICAL RIDGE
OVER THE NEXT 36-48 HOURS.

BY DAY 3 WHEN THE REMNANT CYCLONE IS
OVER THE UPPER-MIDWEST…ISAAC SHOULD TURN EAST-NORTHEASTWARD WHEN
IT INTERACTS WITH WEAK MID-LATITUDE WESTERLY FLOW. THE OFFICIAL
FORECAST TRACK IS JUST AN UPDATE OF THE PREVIOUS ADVISORY
TRACK…AND LIES BETWEEN THE MODEL CONSENSUS AND THE ECMWF MODEL.

STRONG BANDS OF THUNDERSTORMS CONTINUE TO DEVELOP OVER WATER IN THE
THE EASTERN SEMICIRCLE AND ALSO SOUTHWEST OF THE CENTER. THEY HAVE
OCCASIONALLY PRODUCED SUSTAINED TROPICAL-STORM-FORCE WINDS ALONG
WITH GUSTS EXCEEDING 60 KT. THOSE STRONG RAINBANDS WILL GRADUALLY
SPREAD WESTWARD TONIGHT ACROSS THE COASTAL AREAS OF SOUTHEASTERN
LOUISIANA AND SOUTHERN MISSISSIPPI…INCLUDING THE NEW ORLEANS
METROPOLITAN AREA. BY THURSDAY NIGHT…ISAAC COULD WEAKEN TO A
TROPICAL DEPRESSION…AND IT SHOULD BECOME A POST-TROPICAL REMNANT
LOW PRESSURE SYSTEM BY FRIDAY. THERE REMAINS NO INDICATION IN ANY
OF THE NHC MODEL GUIDANCE THAT ISAAC WILL BE ABLE TO ACQUIRE ANY
BAROCLINIC ENERGY THAT COULD CAUSE IT TO STRENGTHEN INTO A
SIGNIFICANT EXTRATROPICAL LOW WHILE IT IS OVER THE UNITED STATES.

SINCE ISAAC WILL CONTINUE TO MOVE SLOWLY OVER THE NEXT 24-36
HOURS…THERE WILL BE A PROLONGED THREAT OF FLOODING FROM HEAVY
RAINS OVER THE NORTHERN GULF COAST AREA AND THE SOUTH-CENTRAL
UNITED STATES.

NATIONAL OCEAN SERVICE TIDE GAGES INDICATE THAT STORM SURGE HEIGHTS
OF NEAR 7 FEET ARE STILL OCCURRING ALONG PORTIONS OF THE COAST OF
SOUTHEASTERN LOUISIANA AND MISSISSIPPI.  GIVEN THE LONG DURATION
OF ONSHORE FLOW IN THESE AREAS…WATER LEVELS ARE EXPECTED TO REMAIN
HIGH THROUGH TONIGHT.

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Oklahoma City forecast from the National Weather Service

Oklahoma City forecast, from the National Weather Service, Norman Forecast Office:

This Afternoon Sunny, with a high near 93. East northeast wind around 13 mph.

Tonight Clear, with a low around 66. East northeast wind 5 to 10 mph.

Thursday Sunny, with a high near 94. East northeast wind 5 to 13 mph.

Thursday Night A 20 percent chance of showers and thunderstorms. Increasing clouds, with a low around 71. East northeast wind 8 to 13 mph.

Friday A 30 percent chance of showers and thunderstorms. Cloudy, with a high near 83. North northeast wind 11 to 15 mph, with gusts as high as 21 mph.

Friday Night A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 72.

Saturday Mostly sunny, with a high near 92.

Saturday Night Mostly clear, with a low around 71.

Sunday Sunny, with a high near 96.

Sunday Night Mostly clear, with a low around 73.

Labor Day Sunny and hot, with a high near 97.

Monday Night Mostly clear, with a low around 73.

Tuesday Mostly sunny, with a high near 95.

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Tropical Storm Isaac potential track from the National Hurricane Center

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Tropical Storm Isaac information from the National Hurricane Center

TROPICAL STORM ISAAC TROPICAL CYCLONE POSITION ESTIMATE
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092012
300 PM CDT WED AUG 29 2012

…ISAAC CONTINUES TO LASH NEW ORLEANS AND THE MISSISSIPPI GULF
COAST WITH VERY HEAVY SQUALLS…

AT 300 PM CDT…2000 UTC…THE CENTER OF TROPICAL STORM ISAAC WAS
ESTIMATED BY NOAA DOPPLER WEATHER RADAR TO BE NEAR LATITUDE 29.9
NORTH…LONGITUDE 90.9 WEST…OR ABOUT 45 MILES SOUTH-SOUTHEAST OF
BATON ROUGE LOUISIANA AND ABOUT 50 MILES WEST OF NEW ORLEANS
LOUISIANA. ISAAC IS MOVING TOWARD THE NORTHWEST NEAR 6 MPH…
9 KM/H…AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE THROUGH
TONIGHT.

DURING THE PAST HOUR…A WIND GUST TO 70 MPH WAS REPORTED AT MARSH
ISLAND LOUISIANA AND A GUST TO 67 MPH WAS REPORTED AT GULFPORT
MISSISSIPPI.

SUMMARY OF 300 PM CDT…2000 UTC…INFORMATION
————————————————–
LOCATION…29.9N 90.9W
ABOUT 45 MI…75 KM SSE OF BATON ROUGE LOUISIANA
ABOUT 50 MI…80 KM W OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS…70 MPH…110 KM/H
PRESENT MOVEMENT…NW OR 310 DEGREES AT 6 MPH…9 KM/H
MINIMUM CENTRAL PRESSURE…975 MB…28.79 INCHES

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Forecast map from the National Weather Service, Tulsa

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Mid-day information on Hurricane Isaac, from the National Hurricane Center

HURRICANE ISAAC INTERMEDIATE ADVISORY NUMBER  34A
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092012
1200 PM CDT WED AUG 29 2012

…ISAAC SOAKING SOUTHEASTERN LOUISIANA AND SOUTHERN MISSISSIPPI
WITH HEAVY RAIN…DANGEROUS COASTAL STORM SURGE AND INLAND FLOOD
THREAT EXPECTED THROUGH TONIGHT…

SUMMARY OF 1200 PM CDT…1700 UTC…INFORMATION
———————————————–
LOCATION…29.7N 90.8W
ABOUT 10 MI…15 KM NW OF HOUMA LOUISIANA
ABOUT 45 MI…75 KM WSW OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS…75 MPH…120 KM/H
PRESENT MOVEMENT…NW OR 310 DEGREES AT 6 MPH…9 KM/H
MINIMUM CENTRAL PRESSURE…973 MB…28.73 INCHES

WATCHES AND WARNINGS
——————–
CHANGES WITH THIS ADVISORY…

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT…

A HURRICANE WARNING IS IN EFFECT FOR…
* EAST OF MORGAN CITY LOUISIANA TO THE MISSISSIPPI-ALABAMA BORDER…
INCLUDING METROPOLITAN NEW ORLEANS…LAKE PONTCHARTRAIN…AND LAKE
MAUREPAS

A HURRICANE WATCH IS IN EFFECT FOR…
* INTRACOASTAL CITY TO MORGAN CITY LOUISIANA

A TROPICAL STORM WARNING IS IN EFFECT FOR…
* EAST OF THE MISSISSIPPI-ALABAMA BORDER TO THE ALABAMA-FLORIDA
BORDER
* MORGAN CITY TO SABINE PASS TEXAS

A TROPICAL STORM WATCH IS IN EFFECT FOR…
* EAST OF HIGH ISLAND TEXAS TO JUST WEST OF SABINE PASS

FOR STORM INFORMATION SPECIFIC TO YOUR AREA…PLEASE MONITOR
PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST
OFFICE.

DISCUSSION AND 48-HOUR OUTLOOK
——————————
AT 1200 PM CDT…1700 UTC…THE CENTER OF HURRICANE ISAAC WAS
LOCATED BY NOAA DOPPLER WEATHER RADAR NEAR LATITUDE 29.7 NORTH…
LONGITUDE 90.8 WEST. ISAAC IS MOVING TOWARD THE NORTHWEST NEAR 6
MPH…9 KM/H. THIS GENERAL MOTION IS EXPECTED TO CONTINUE THROUGH
TONIGHT…FOLLOWED BY A TURN TOWARD THE NORTH-NORTHWEST BY THURSDAY
NIGHT OR EARLY FRIDAY. ON THE FORECAST TRACK…THE CENTER OF ISAAC
WILL MOVE FARTHER INLAND OVER LOUISIANA TODAY AND TOMORROW…AND
MOVE OVER SOUTHERN ARKANSAS BY EARLY FRIDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 75 MPH…120 KM/H…WITH HIGHER
GUSTS. ISAAC IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON
HURRICANE WIND SCALE. GRADUAL WEAKENING IS FORECAST DURING THE NEXT
48 HOURS AS ISAAC CONTINUES MOVING FARTHER INLAND…AND ISAAC IS
EXPECTED TO WEAKEN TO A TROPICAL STORM LATER TODAY.

HURRICANE-FORCE WINDS EXTEND OUTWARD UP TO 45 MILES…75 KM…FROM
THE CENTER…AND TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 175
MILES…280 KM.

A GUST TO 71 MPH WAS RECENTLY REPORTED AT PILOT STATION NEAR THE
MOUTH OF THE MISSISSIPPI RIVER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE BASED ON NEARBY SURFACE
OBSERVATIONS IS 973 MB…28.73 INCHES.

HAZARDS AFFECTING LAND
———————-
STORM SURGE…THE COMBINATION OF A STORM SURGE AND THE TIDE WILL
CAUSE NORMALLY DRY AREAS NEAR THE COAST TO BE FLOODED BY RISING
WATERS. THE WATER COULD REACH THE FOLLOWING DEPTHS ABOVE GROUND IF
THE PEAK SURGE OCCURS AT THE TIME OF HIGH TIDE…

* MISSISSIPPI AND SOUTHEASTERN LOUISIANA…6 TO 12 FT
* ALABAMA…3 TO 6 FT
* SOUTH-CENTRAL LOUISIANA…3 TO 6 FT
* FLORIDA PANHANDLE AND APALACHEE BAY…2 TO 4 FT

THE DEEPEST WATER WILL OCCUR ALONG THE IMMEDIATE COAST IN AREAS OF
ONSHORE WINDS.  SURGE-RELATED FLOODING DEPENDS ON THE RELATIVE
TIMING OF THE SURGE AND THE TIDAL CYCLE…AND CAN VARY GREATLY OVER
SHORT DISTANCES.  FOR INFORMATION SPECIFIC TO YOUR AREA…PLEASE
SEE PRODUCTS ISSUED BY YOUR LOCAL WEATHER SERVICE OFFICE.  NEAR THE
COAST…THE SURGE WILL BE ACCOMPANIED BY LARGE AND DANGEROUS WAVES.

STORM SURGE VALUES OF ABOUT 8 FEET HAVE RECENTLY BEEN REPORTED AT
SHELL BEACH LOUISIANA AND WAVELAND MISSISSIPPI.

WIND…TROPICAL STORM CONDITIONS WILL CONTINUE ACROSS THE WARNING
AREA TODAY…AND HURRICANE CONDITIONS WILL CONTINUE TO AFFECT
PORTIONS OF SOUTHEASTERN LOUISIANA AND MISSISSIPPI IN THE HURRICANE
WARNING AREA INTO THIS AFTERNOON.

WINDS AFFECTING THE UPPER FLOORS OF HIGH-RISE BUILDINGS WILL BE
SIGNIFICANTLY STRONGER THAN THOSE NEAR GROUND LEVEL. AT ABOUT THE
30TH STORY…WINDS WOULD LIKELY BE ONE SAFFIR-SIMPSON CATEGORY
STRONGER THAN AT THE SURFACE.

RAINFALL…ISAAC IS EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF
7 TO 14 INCHES…WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF 20
INCHES…OVER MUCH OF LOUISIANA…SOUTHERN MISSISSIPPI…AND
SOUTHWEST ALABAMA THROUGH FRIDAY MORNING. THESE RAINS COULD RESULT
IN SIGNIFICANT LOWLAND FLOODING. RAINS ARE EXPECTED TO INCREASE
NORTHWARD INTO ARKANSAS ON THURSDAY…WITH AMOUNTS OF 3 TO 6 INCHES
EXPECTED OVER SOUTHERN ARKANSAS BY FRIDAY MORNING.

TORNADOES…ISOLATED TORNADOES ARE POSSIBLE ALONG THE CENTRAL GULF
COAST REGION AND PARTS OF THE LOWER MISSISSIPPI RIVER VALLEY
THROUGH THURSDAY.

SURF…DANGEROUS SURF AND RIP CURRENT CONDITIONS WILL CONTINUE TO
AFFECT THE WEST COAST OF FLORIDA AND THE NORTHERN GULF COAST FOR THE
NEXT DAY OR SO.

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