This information is provided for informational purposes only and is not intended to be a substitute nor should it be used in place of official information. Please follow and obey orders from local emergency management officials.
Hurricane Ivan - Tuesday - September 14, 2004 - 9:30 PM
***IVAN TAKING FINAL AIM ON GULF COAST***
*PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE RUSHED TO COMPLETION WEDNESDAY*
**BARRIER ISLANDS FROM GULFPORT MS EAST TO SANTA ROSA COUNTY FL SHOULD BE EVACUATED AT ALL COSTS**
**ALL EVACUATION ORDERS SHOULD BE FOLLOWED**
CURRENTLY: I have little if any change to my thinking from 24 hours ago. The gulf coast from Biloxi, MS east to Pensacola, FL should be making final preparations over the next 16-20 hours to protect life and property from a direct hit by a major hurricane.
Ivan has essentially been a steady state since late morning/early afternoon. Pressure has been hovering around 930 mbs for the last 12 or so hours…up a little, down a little. Any weakening trend that started near daybreak has halted. The eye diameter is large…in excess of 30 miles.
Ivan has been moving N.N.W. (330-335 degrees) for the better part of the last 20 hours or so. This motion should continue for the next 24-36 hours (or up until landfall) with a slightly more northward bend beyond 24 hours. Forward speed today has slightly increased from 8 to the current 10 or 11 mph. Expect forward motion to remain between 10-15 mph up until landfall..when Ivan could slow to under 10 mph.
Latest satellite pictures show a hurricane that is in no hurry to weaken and who's circulation is trying to dominate the atmosphere around it. It is literally shoving what shear there is out of the way on its western side as well as a wedge of drier air….this clearly evidenced by Ivan's expanding cirrus canopy and the erosion of the drier air to the N.W. of the Ivans circulation.
INTENSITY: As mentioned last night Ivan will be moving over a warmer eddy of water later tonight and tomorrow. With only modest shear forecast now…Ivan should essentially maintain moderate to strong Cat 4 (135-145 mph) intensity for the next 24 hours. Beyond 24 hours and out to about 33 hours…or time of landfall…Ivan will have passed over the warm eddy and shear should increase further.
Hopefully this will send Ivan onshore as a hurricane that is in weakening mode….still looking for 125 mph at landfall +/- 10 mph……although if I had to lean one way or the other..… I'd lean to the +10…or 135 mph.
This intensity forecast is going to be a dicey call, as mentioned last night we may have to wait for the 12 hours prior to landfall to see the most weakening….this would come from increasing westerly shear, "cooler" waters and a slow movement causing some upwelling of the shallow water. No matter how you slice it a major hurricane will be moving onshore the gulf coast in about 30-33 hours.
This is a major hurricane and is capable of producing significant damage. The area of the Gulf coast Ivan is forecast to affect is very prone to storm surge. Depending on the tide cycle (high or low) storm surge could be in the vicinity of 15 feet.
Latest 00Z SHIPS is about 115 kts (130-135 mph) at time of landfall…really can't find anything to disagree with there.
If you are asked to evacuate….DO IT !
Holding my position….Biloxi, MS east to Pensacola, FL is my swath for landfall….with highest threat from the MS/AL line to the AL/FL line…or the coast of Alabama.
As far as Mobile is concerned…this has potential to be very bad. If Ivan comes up into Mobile Bay or worse yet up over Dauphin Island into Mobile county the surge could be extreme….with a 12-16' surge plowing up Mobile bay. I can't make this call yet because I'm not sure if Ivan comes onshore west of, east of or over the bay….stay tuned. That 12-16' surge assumes a 130 mph hurricane at landfall. There would be waves on top of that surge as well.
Ivan has a very large wind field and water levels are already rising and will continue to rise long before the hurricane makes final approach.
As mentioned in the 3:00 update this afternoon it is a possibility that Ivan drifts east along the coast for a short time before fully coming inland. Steering currents will be weak and with such a well stacked and strong hurricane friction could cause it to sort of skid along the coast for a while. Will have to watch for this possibility as we get closer. If steering currents are just strong enough Ivan will just slowly move inland.
With the large wind field a large swath of the coast from the mouth of the Mississippi east to the eastern FL panhandle will see large waves and rough surf. As I've been saying the worst of all this will be near and to the right of where the center crosses…so from that aspect it is key where the center of Ivan crosses the coast.
Timing of landfall….between 4:00 A.M. and 10:00 A.M. Thursday.
My track is in good agreement with the latest TPC 5:00 projection…perhaps just a little to the right.
Remember, even though the worst weather will be near and to the right of landfall…Ivan has a wide sweeping wind field….hurricane force winds (75 mph) extend out 100 mph from the center and winds to tropical storm force extend out to 250 miles. A very large area is going to be impacted by Ivan. Winds to hurricane force will likely extend well inland….tree and powerline damage is going to be very extensive…..it would not surprise me in the least to see total power restoration take upwards of 3 weeks.
Impacts: Expect a storm surge of 12-16' near and to the right of where the center crosses the coast. This will swamp some of the barrier islands along with battering waves. There will also be significant water rises a good distance east of where the center crosses…along with very rough surf, swells and beach erosion. Intense hurricane force winds 115 mph + will affect an area near and to the right of where the center comes in….assuming a 125 mph hurricane at landfall…gusts could approach 140 mph near the core of the hurricane..along the barrier islands and the immediate coast.
Rainfall of 6-12", with some locally higher amounts will affect a large area producing flooding.
Once onshore, Ivan will move SLOWLY North or NNE inland over Alabama….high winds will extend well inland and tree/powerline damage will be very extensive well up into Alabama.
Since Ivan will move only slowly, rainfall amounts inland through Alabama into eastern KY, TN and the western Carolinas could exceed 15"…this will be a big problem over the western parts of the Carolinas that just received 12"+ rains from Frances….flooding there could be extreme….I don't want to over estimate the inland flood threat here but if everything fell into place the inland flooding could be catastrophic. More on this tomorrow.
Folks, I'm not a hype monger….if anything I'm probably a little low key….the upside potential with Ivan is large. PLEASE take this seriously. If you live along the immediate coast or on a barrier island and you stay…you are playing with your life.
Next update…..3:00 tomorrow afternoon.
Just in….latest recon message has pressure down another mb..to 928….Max flight level wind was 147 kts. (170 mph) this would translate to a surface wind of about 150 mph….so it is possible if not likely TPC will increase the winds in the next advisory. Recon also reports a 43 mile wide eye…..that means it has a while to go before it contracts down….as mentioned above Ivan shows no signs he is an any hurry to weaken.
Also, just a word about New Orleans….this is not, nor has it ever been in my mind a doomsday scenario for New Orleans….not once in the last few days did I even hint I was concerned about New Orleans going under water. The media needs to chill a bit. Jeeez.
THIS INFORMATION IS FOR INFORMATIONAL PURPOSES ONLY. IT IS NOT A SUBSTITUTE FOR OFFICIAL INFORMATION.
Please refer to official statements from TPC and local weather services offices for official information. Please obey all evacuation orders as issued by local emergency service offices.