Brief news report by Kip Hansen — September 9, 2024
Just in time for “peak hurricane season deadline,” NOAA National Hurricane Center announces Potential Tropical Storm Six become Tropical Storm Francine:
Monday, September 9, 10:00 AM CDT
Location: 23.0° north latitude, 94.9° west longitude
Movement: NNW, speed 5 mph
Minimum pressure: 1002 mb
Maximum sustained speed: 50 mph
From the discussion section:
“Tropical Storm Francine Discussion 4
NWS National Hurricane Center Miami FL AL062024
Monday, September 9, 2024 at 1000 AM CDT
The structure of satellite imaging systems improves this
In the morning, there is a large circular cold convection area between -70℃
to -85 near the estimated center. air force reconnaissance
The aircraft is sampling the system this morning and one was discovered earlier
Cyclonic winds shift from southeast to northwest
Center of deep convective mass. These data are sufficient to provide
There is evidence that a clear loop now exists, so PTC
No. 6 has become Tropical Storm Francine, with sustained winds of
45 carats for this consultation.
Estimating motion remains tricky given the recent emergence of the center
It has formed, but is still estimated to be moving north-northwestward at 340/4
kt. The system is expected to gradually turn northward and then
As it moves between ridges centered on the Zhongshan Ridge, it moves north-northeast
The broad mid- to upper-level trough over Cuba and its vicinity
Northwest Texas. There have been some changes to guidance this cycle
Eastward and faster, NHC track forecast again
Push in that direction. Current track evenly divided
Between HCCA and TVCN, Francine is still shown coming ashore
Louisiana sometime Wednesday night. still have a decent
The amount of trajectory uncertainty shown by the GEFS and EPS ensembles
Propagation along the track means there are some speed differences near landing.
Although the system is now a tropical storm, the inner core wind field
The scope of reconnaissance observation remains broad and within the organization
Phase, initial reinforcement will be gradual. However, after
A kernel has been established and it is assumed that the cyclonic
Vertical structure becomes consistent, a more important period
Storms can intensify when they are embedded in low shear,
Medium to high humidity, sea surface temperature very warm 30-31 C
temperature. SHIPS rapid enhancement (RI) index is
Quite high, RI stage can also occur between 24-48
h. At present, the National Health Commission’s intensity forecast will not clearly predict
RI, but higher than the previous cycle and showing a 75 kt peak
48 hours, very consistent with strength consensus aid. back
During this period, the vertical shear of southwesterly winds increased rapidly.
Strength may level off from 10 knots to over 30 knots
near the northwestern U.S. Gulf Coast coastline, although the system
It is expected to remain a hurricane when it makes landfall. NHC strength
Forecasts remain very consistent with consensus aid,
But it is a bit lower than the HAFS-A/B and COAMPS-TC models.
A hurricane watch has been issued based on the latest forecast
Louisiana coastline and storms from Cameron to Grand Island
Already heading east from High Island, Texas
Mississippi/Alabama border.
So for the season so far, we now have:
######
Author comments:
The 2024 hurricane season is slightly less than 50% likely compared to historical records.
The two- and seven-day forecasts show some of what's happening – the potential to develop into a tropical storm.
This is news.
######
Relevant
