The National Weather Service in New Orleans has issued a Coastal Flood Advisory, which is in effect from 7am Monday to 7pm Tuesday.
* COASTAL FLOODING – 1 to 2 feet above ground level for portions of coastal Mississippi, portions of the Louisiana coast east of the Mississippi River outside of the hurricane protection levees, and along the shores of Lake Pontchartrain and Maurepas outside of the hurricane protection levees. Around one foot above ground level for areas along the Louisiana coast west of the Mississippi River.
* TIMING – Peak coastal flooding should occur during high tide both Monday and Tuesday.
* IMPACTS – Flooding of low lying coastal roads outside of the hurricane protection levees.
PRECAUTIONARY/PREPAREDNESS ACTIONS: A Coastal Flood Advisory indicates that onshore winds and tides will combine to generate flooding of low areas along the shore.
Changes from the last 24 hours:
· Tropical Storm Michael continues to strengthen, and is now forecast to be a category 2 hurricane at landfall along the coast of Florida.
· The track has shifted slightly further to the east from the previous advisory.
· A Coastal Flood Advisory is now in effect for Monday and Tuesday.
What we know:
· A category 1 or 2 hurricane is likely to be moving through the northern Gulf late Tuesday and Wednesday
· Strengthening easterly and southeasterly winds over the Gulf are expected to lead to higher than normal tides Monday and Tuesday along east and southeast facing shores of Louisiana and Mississippi. This will be well in advance of any direct impacts from the tropical system. 1 to 2 feet of coastal flooding above ground level could occur along portions of the Mississippi coast, the shores of Lake Pontchartrain and Maurepas outside of the hurricane protection levees, and east facing shores of Louisiana east of the Mississippi River outside of the hurricane protection levees. Flooding of low lying roads outside of the hurricane protection levees will be possible.
What’s less certain:
· Exact local impacts such as maximum wind speeds and rainfall amounts – which are heavily dependent on the eventual track and intensity of the system
· Model guidance and the current official forecast indicate the system will move through the central Gulf and approach the northern Gulf Coast before turning more to the northeast. If that scenario verifies, the more significant impacts should remain east of the local area. However, if the forecast track shifts westward or if any of the storm’s outer bands move through the area, strong/gusty winds and heavy rainfall COULD affect parts of southeast Louisiana and southern/coastal Mississippi.
· The current storm total rainfall forecast generally indicates less than 2 inches of rain throughout the event for southeast Louisiana and southern/coastal Mississippi. However, it should be noted that totals could be significantly higher if any bands result in multiple storms passing over the same areas.