Sept 10, 2024 Hurricane Francine

After a period of struggling against dry air, Francine set to intensify perhaps to Category 2

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Francine intensifies into a hurricane | Pressure 982 mb

The central pressure of Francine has fallen a bit faster in the past 6-hours, but the rapid intensification mentioned by NHC did not occur as expected. However, the smaller inner core — after shedding the large convective blob yesterday — is much more compact and conducive to rapid pressure falls — and then intensification of the wind speeds.

A hint about the potential intensification is seen with 18z suite of HAFS-A and HAFS-B mesoscale models that show maximum intensity in the Category 2 range with pressure in the 960s rising to low-970s at landfall.

There is a lot of wind energy with Francine w/850 hPa wind speeds > 100-knots and the gusts well over 100-knots around the compact eye. This is typical with a young or developing tropical cyclone prior to any eyewall replacement cycles, which won’t be happening before landfall in Louisiana.

New Orleans should keep close watch on Francine.

HAFS-B has a massive convective blow-up into the overnight hours with the diurnal maximum. This would be quite impressive — so we’ll watch in the next few hours for any thunderstorms blowing up.

ECMWF HRES 12z

Central pressure at 978 mb is consistent with previous forecast cycles as well as the landfall location. However, with the current pressure at 982 mb, this may be much lower at landfall.

HRRR Simulated Radar

The eye seems to remain mostly intact until landfall — with more of an east track. Plenty of rainfall spreads inland through Mississippi. New Orleans was in the area of high impact with potentially hurricane force wind gusts and 10-inches of rainfall.

NHC Forecast Track

10-feet of storm surge — could be more as Francine pushes a wall of water onshore.

Rainfall Next 3-days

Heaviest amounts along the Louisiana coastline, of course. New Orleans in the 4-inch range, but I think that could go up with a more eastward track.

Inland wind gusts > hurricane force are possible but hard to determine the exact path since it will be so narrow. However, hurricanes decay rapidly as they move inland dependent upon the forward motion. Francine is moving fairly quickly, so strong/damaging winds 50-100 miles inland into Mississippi quite possible.

Atlantic IR Satellite

The 7-Day NHC Outlook