Here's the latest on Hurricane Isaac:
As of 11 a.m. EDT
Max sustained winds: 75 mph
Movement: NW @ 6 mph
Location: About 45 miles southwest of New Orleans
Minimum pressure: 972 millibars
Latest discussion and 48-hour from the National Hurricane Center:
DISCUSSION AND 48-HOUR OUTLOOK
AT 1000 AM CDT...THE CENTER OF HURRICANE ISAAC WAS
LOCATED BY NOAA DOPPLER WEATHER RADAR NEAR LATITUDE 29.6 NORTH...
LONGITUDE 90.7 WEST...OR VERY NEAR HOUMA LOUISIANA. 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 OVER SOUTHERN ARKANSAS BY EARLY
MAXIMUM SUSTAINED WINDS HAVE DECREASED TO 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
A GUST TO 74 MPH WAS RECENTLY REPORTED AT THE MID LAKE STATION IN
LAKE PONTCHARTRAIN...AND A WIND GUST TO 63 MPH WAS REPORTED AT
NEW ORLEANS INTERNATIONAL AIRPORT.
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
STORM SURGE VALUES OF NEAR 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.
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.
TORNADOES...ISOLATED TORNADOES ARE POSSIBLE ALONG THE CENTRAL GULF
COAST REGION AND PARTS OF THE LOWER MISSISSIPPI RIVER VALLEY
This is a slow mover! Take a look at the forecast through early Thursday morning and how little the storm is forecast to move:
*Note the data on the right-hand-side was as of 8 a.m. Wednesday, winds as of 11 a.m. have subsided to 75 mph.*
I realize the data will get dated very quickly, thus you can get the very latest on the storm stats here:
A frontal boundary and high pressure is pushing south, while Hurricane Isaac tries to move northwest. This is why the storm is moving so slowly. The greens on this water vapor imagery show the mid and high level moisture in the atmosphere. The brown and darker areas signify drier air. That broad 'u' shape is associated with a high to the north that is limiting how fast this storm moves inland. Thus flooding will certainly be the biggest threat under this hurricane.
The winds have been pretty decent. I've seen reports of wind gusts of higher than 100 miles per hour, while sustained winds have remained around 80 mph. If you recall, Hurricane Katrina had much stronger winds when it slammed into New Orleans. That storm was a category 3, while Isaac is a 1. In other words Katrina had winds between 111 and 129 mph. Isaac will probably produce more rain though, between 12 and 20 inches in parts of Louisiana. Katrina dropped 10-15 inches. However it's hard to say whether the flooding will be worse with this storm. While more rain will fall, the storm surge will be much less than Katrina, which if you recall pushed through the levees and caused that devastating flooding.
When I came into work this morning at 3 a.m. and started checking out the storm via power outages, rainfall, winds, etc. I saw about 300,000 power outages via Entergy. As of 10:30 a.m. Wednesday those power outages rose to affect 525,000 people. This will be a long day for sure in New Orleans, Mississippi, and the rest of Louisiana. Tropical storm force winds are likely to last through Thursday morning as well as very heavy rainfall.
One last thought: We could see some rain from this event down the road. Moisture associated with Isaac is expected to move north and eventually east through Missouri, Illinois, Ohio, and possibly the Northeast and New England. This would come through our area Tuesday based on the latest projections and give us about an inch of rain. However it's still early to tell, and don't worry about any post-tropical affects with flooding because our ground can handle a lot of moisture due to how dry is hast been lately.
-Meteorologist Steve Glazier