Tropical System Ian

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Key Messages:
1. Ian is expected to produce heavy rainfall, flash flooding, and
possible mudslides in areas of higher terrain, particularly over
Jamaica and Cuba. Flash and urban flooding is possible with
rainfall across the Florida Keys and the Florida peninsula through
the middle of the week. Additional flooding on rivers across
northern Florida and parts of the southeast U.S. cannot be ruled out
later this week.

2. Life-threatening storm surge and hurricane-force winds are
expected in portions of western Cuba beginning late Monday, and Ian
is forecast to be at or near major hurricane strength when it is
near western Cuba. Efforts to protect life and property should be
rushed to completion.

3. Ian is expected to be a major hurricane in the eastern Gulf of
Mexico during the middle of this week, but uncertainty in the track
and intensity forecasts remains higher than usual. Regardless of
Ian’s exact track and intensity, there is a risk of dangerous storm
surge, hurricane-force winds, and heavy rainfall along the west
coast of Florida and the Florida Panhandle by the middle of this
week, and residents in Florida should ensure they have their
hurricane plan in place. Follow any advice given by local officials
and closely monitor updates to the forecast.

My home has gone from 10% chance to 60% chance of being in the path of Ian in the past 12 hours.

Aside from its relatively brief time passing over western Cuba, Ian
will be moving over waters of very high oceanic heat content during
the next couple of days. The various Rapid Intensification (RI)
indices show a significant probability of RI and this is reflected
in the short-term official intensity forecast. However, the SHIPS
guidance, which is based on global model predictions, indicates that
a significant increase in southwesterly shear and a substantially
drying of low- to mid-level air will begin in 24-36 hours. The NHC
forecast, like the previous one, shows strengthening to Category 4
intensity in a day or so, followed by gradual weakening. However,
Ian is still expected to be a major hurricane when it reaches the
Florida west coast.

The hurricane is expected to move north-northwestward to northward
over the southeastern Gulf of Mexico during the next day or so,
along the western periphery of a subtropical ridge. After around
36 hours, the track forecast becomes more uncertain, since there is
considerable divergence of the track models in the 2-3 day
time frame. The guidance also shows considerable slowing of the
forward speed, due to a weakening of the steering currents, when
Ian approaches the west coast of Florida. This slower forward
motion is likely to prolong the storm surge, wind, and rainfall
impacts, especially along the west coast of Florida.

Key Messages:
1. Life-threatening storm surge, hurricane-force winds, flash floods
and possible mudslides are expected in portions of western Cuba
beginning overnight and continuing into Tuesday. Devastating wind
damage is possible where the core of Ian moves across western Cuba.
Efforts to protect life and property should be rushed to completion.

2. There is a danger of life-threatening storm surge along much
of the Florida west coast where a storm surge warning has been
issued, with the highest risk from Fort Myers to the Tampa Bay
region. Residents in these areas should listen to advice given by
local officials.

3. Hurricane-force winds are expected in the hurricane warning area
in west-central Florida beginning Wednesday morning with tropical
storm conditions expected by late Tuesday.

4. Heavy rainfall will spread across western Cuba through Tuesday.
This will likely produce instances of flash flooding and possible
mudslides in areas of higher terrain over western Cuba.

5. Heavy rainfall will increase across the Florida Keys and South
Florida Tuesday, spreading into central and northern Florida
Wednesday and Thursday and the Southeast by Friday and Saturday,
potentially causing flash, urban and small stream flooding.
Considerable flooding, including significant, prolonged river
flooding, is likely across Central Florida.

Hurricane Ian Discussion Number 17
NWS National Hurricane Center Miami FL AL092022
500 AM EDT Tue Sep 27 2022

Ian is expected to spend only spend a few hours over western Cuba,
and little overall change in strength is likely during that time.
The center should emerge over the southeastern Gulf of Mexico later
this morning, where warm water and generally low vertical wind shear
conditions are expected to allow for additional intensification, and
the NHC forecast calls for Ian to reach category 4 strength. By 24
to 36 hours, increasing southwesterly vertical wind shear and drier
mid-level air are likely to result in some gradual weakening.
However, Ian is still expected to be a major hurricane when it
reaches the Florida west coast.

There continues to be larger-than-normal
spread in the track guidance by 36-48 hours, however the trend in
the global models has been more southward and eastward over the
last cycle or two. As a result, the NHC track has been adjusted to
the southeast of the previous forecast and it lies just west of the
TVCA multi-model consensus aid. Users are reminded to not focus on
the exact track as some additional adjustments to the track are
possible, and wind, storm surge, and rainfall hazards will extend
far from the center. The updated forecast track has necessitated
several changes to the warnings and watches across the Florida Keys
and Florida peninsula, including an extension of the Hurricane
Warning southward to Bonita Beach on the west coast.


Key Messages:
1. Life-threatening storm surge, hurricane-force winds, flash
floods and possible mudslides are expected in portions of western
Cuba today. Devastating wind damage is expected where the core of
Ian moves across western Cuba this morning.

2. There is a danger of life-threatening storm surge along much
of the Florida west coast where a storm surge warning has been
issued, with the highest risk from Fort Myers to the Tampa Bay
region. Residents in these areas should listen to advice given by
local officials.

3. Hurricane-force winds are expected in the hurricane warning area
in west-central Florida beginning Wednesday morning with tropical
storm conditions expected by late today.

4. Heavy rainfall will spread across western Cuba through Tuesday.
This will likely produce instances of flash flooding and possible
mudslides in areas of higher terrain over western Cuba.

5. Heavy rainfall will increase across the Florida Keys and South
Florida Tuesday, spreading into central to northern Florida
Wednesday and Thursday, and the Southeast by Friday and Saturday,
likely causing flash, urban, and small stream flooding.
Considerable flooding is expected across Central Florida into
southern Georgia and coastal South Carolina, with significant,
prolonged river flooding expected across central to northern
Florida.

HURRICANE IAN UPDATE: Powerful Hurricane Ian's initial assault on Florida is underway

Hurricane Ian is leaving Cuba behind and heading into the Gulf of Mexico. It has rapidly intensified – approaching Category 4 status. And there's no reason to think it won't get even stronger today. Ian is forecast to be an extremely powerful hurricane offshore of Southwest Florida by early tomorrow. Then the forecast gets complicated. The core threat zone has widened on the west coast of Florida.

By tomorrow afternoon, the steering currents are forecast to collapse, and it is less clear where the storm will drift than we thought yesterday. The official National Hurricane Center forecast continues to crawl the hurricane toward the general area from Tampa Bay to Sarasota – a slight shift to the south from yesterday's forecast. But too-small-to-forecast factors could still come into play, which makes the exact landfall point impossible to predict.

A rule of hurricane forecasting is to beware of slow-moving storms. Since there is no established river of air to carry them along, small weather systems or internal processes can push or pull stalled storms one way or the other.

There is a solid track consensus among the computer models until the storm's center gets near the Florida coast during the day tomorrow. Ian will stall or crawl through the next part of its track. This is when the path becomes highly uncertain.

Slow or stalled storms won't go anywhere fast, but the end result can be something unexpected. Sometimes stalled storms will loop or reposition themselves, so they eventually head in a different direction than they were moving prior to the stall.

In addition, a stalled or slow-moving system prolongs the punishment on the affected areas.

The track adjustment does not take the pressure off the Tampa Bay area. Ian could drift north just offshore, or it could drift inland just to the south. Those very different tracks aren't much far apart geographically but make a tremendous difference in which areas get how much storm surge.

The fact that the hurricane now appears it will stall near or south of Tampa Bay also means that stronger onshore winds will likely extend farther down the coast to include the Fort Myers/Port Charlotte area, where Hurricane Warnings are now in effect

Another unfortunate offshoot of the farther-south stall point is that Ian won't get as far north where it was forecast to weaken. Now it appears that a Category 3 or 4 hurricane will sit near or over the west-central coast of Florida.

Besides the Hurricane Warnings, which are flying along the Florida west coast, high wind alerts are in effect for most of the peninsula. Widespread power outages are likely.

In addition, the stalled hurricane will combine with a cold front across north Florida to produce a corridor of extreme rainfall – perhaps reaching 2 feet. The ultra-intense rain zone extends from the Tampa/Sarasota area near the center of the storm to Jacksonville, plus or minus. Everybody in North Florida needs to be on high alert. This will be extremely dangerous.

In addition, the entire panhandle will be impacted by intense bands of rain feeding into the circulation. Widespread 5 to 10 inches with some areas receiving a foot or more of rain are forecast. The periods of rain will be relentless this week.

In addition, tornadoes will be embedded in those feeder bands as they rotate off the Gulf or Atlantic.

Extreme, life-threatening storm surge will affect many areas on the west coast. The Gulf water will rise over the coast or into rivers and bays and push inland with force. It is imperative that everybody in affected areas listen to their local officials and follow their instructions about evacuation.

Due to a combination of Ian's possible track over the northern peninsula and the strong northeast winds related to the coming cold front and the strong high pressure behind it, there is a significant storm surge threat in the Jacksonville area and along the Georgia coast. The situation is not dissimilar to what happened during Hurricane Irma.

Winds will increase through the Lower and Middle Florida Keys today, which will push ocean water against the Keys. Eventually, the winds will switch to west and northwest, which will push Gulf water into Florida Bay. This will take days. Flooding of low-lying areas is expected.

Central Florida will experience strong winds with some gusts reaching hurricane force if Ian follows anything like the National Hurricane Center's track. Everyone needs supplies for a week without power and to carefully think about where to park the car.

Winds over 40 mph with gusts near hurricane force are also expected along the Central and North Florida east coast.

The entire Florida peninsula is threatened to one degree or the other. Now is the time to think hard about your situation. Be sure you are in a safe place, and you have supplies to take care of yourself and your family. What you do now will make a huge difference in how your post-hurricane period works out.

Ian is headed for Tampa and some mandatory evacuations have been ordered.

Ian is veering a bit more in my direction. I’ll have to get plywood on the windows today and batten down the hatches best I can. When Irma hit, the winds were terrifying. There were loud bangs and crashes and things hitting the house. It sounded like the house was going to be destroyed, but when it was over there was little actual damage to the house, even though several large trees hit the house.

The power grids will probably go down and I may be cut off for days to weeks.

HURRICANE IAN LANDFALL DAY: Powerful Hurricane Ian a worst-case scenario for Southwest Florida

It’s fair to say that prominent parts of Southwest Florida from south of Fort Myers to north of Charlotte Harbor – about 50 miles of coastline – will be changed forever.

Gulf water will top most of the barrier islands destroying many or most structures. People left in the storm-surge zone may not survive. The surge will arrive this afternoon.

The hurricane is as bad as it can be. The winds are not yet Category 5, butthe diameter of the storm has expanded, which is worse. The bigger donut of winds moves more water making storm surge higher. The slow forward progress of this storm will add to the height of the surge.

The forecast is for 12 to 16 feet of Gulf water above the normal HIGH tide level. This will push water over the islands and the coastline, into the harbors, and up the rivers and over their banks at deadly heights. The surge can go up to 10 miles inland, depending on the river.

A large part of Cape Coral and Fort Myers along the Caloosahatchee River are likely to go underwater.

High tide comes this afternoon about the time the surge will peak for some areas in the Greater Fort Myers area. This will add a couple feet to the surge. The tide is already extra high because we’re in King Tide season.

The Naples areas will see slightly less, 7 to 11 feet of water rise is still forecast near the coast this afternoon.

Destructive winds will rip through Southwest Florida today. On the north side of the storm the winds will come in bands with torrential rain. Because the storm is interacting with a front across North Florida, an intense corridor of rain will develop across the entire peninsula from Tampa Bay through Central Florida. Damaging winds of hurricane strength will occur in that intense band, although those gusts won't be as destructive as the winds on the south side of the circulation.

Over 2 feet of rain will likely fall in parts of Central and North Florida over the next couple of days as Ian slowly makes its way north. The rest of Florida will be affected by Ian’s spiral bands, and some embedded tornadoes expected. But dry air is forecast to rotate into the bottom of the circulation, so the southern Florida peninsula will receive less total rain.

Hurricane force winds will move into Central Florida tomorrow with torrential downpours continuing. The peak winds will diminish as the center of the storm moves across the state, but the gustiness will increase while the circulation is over land.

In North Florida, storm surge will be significant as well. People in the Jacksonville should remember Hurricane Irma and the major flooding in and around the St. Johns River and along the coast. And the coastal flood threat will continue north into South Carolina.

This is an unprecedented storm for Southwest Florida. The closest in the history book occurred in 1873 when Fort Myers was a small village. It is critical that people not try to compare it to any previous storm.

Every possible step needs to be taken immediately for personal safety.