Why meteorologists feel sick about Hurricane Ian

Ian's meteorology looks really, really bad for Tampa

There’s a reason why the director of the National Oceanic and Atmospheric Administration’s National Hurricane Center (NHC) reportedly called Hurricane Ian a “near worst-case scenario” for Tampa.

Actually multiple reasons.

Hurricane Ian looks to be taking the shape of a long-studied and feared near-direct strike from a major hurricane on the greater Tampa Bay area.

Let’s start with the best official information on Ian as of this post. The official NHC forecast calls for Ian to intensify into a major Category 4 hurricane with 140 mph winds by Wednesday.

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The most likely track puts Ian just west of the Tampa Bay area Wednesday into Thursday.

Hurricane Ian
Hurricane Ian's official forecast track.

Multiple risk factors

I sent this tweet today with the main factors for Ian.

Let’s break Ian’s risk factors down a little more below.

A major hurricane striking a large U.S. city is bad enough. But Ian’s meteorology and local geography pose higher risks for the Tampa area than other storms in other places.

First the meteorology.

Storm track

Most forecast models take Ian’s track near or just west of the Tampa area late Wednesday and Thursday. This track would put the stronger right side of the storm’s highest winds and surge into the greater Tampa Bay area.

Current storm surge forecasts depict between 5 and 10 feet of surge in and around Tampa Bay.

Hurricane Ian storm surge
Hurricane Ian storm surge forecast.

Ian may stall

Many forecast models suggest Ian will slow/stall just west of Tampa for 24 to 36 hours. That means prolonged battering by storm surge, hurricane-force wind, and waves. That would produce prolonged damaging effects from Wednesday into Friday morning.

Here is the European Centre for Medium-Range Weather Forecasts 12Z model:

European model (ECMWF) output
European model output for Hurricane Ian through Thursday
European Centre for Medium-Range Weather Forecasts, via Tropical Tidbits

A slow-moving or stalled hurricane is a horrible scenario for Tampa. Wind, waves, and storm surge battering the area for 24 to 36 hours would prolong the damage potential compared to a fast-moving storm.

Tampa’s unique hurricane geography

Tampa’s ocean and hurricane geography make it one of the most vulnerable locations on earth to a major hurricane strike. The ocean floor near Tampa is shallow. That enhances storm surge.

And the shape of Tampa Bay can act like a funnel. Storm surge from southwest winds on the right side of a passing hurricane rush into Tampa Bay. The water has nowhere to go but onshore. The land around Tampa Bay is low-lying in most areas.

So if the projected 5 to 10-foot storm surge occurs, it will inundate highly populated cities and neighborhoods around the greater Tampa area.

The bottom line is if current forecasts by the world's best hurricane scientists and forecast models for Ian pan out we are looking at a potentially devastating scenario for parts of Florida's west coast.

There’s still hope that Ian’s forecast track could jog west in tomorrow’s forecast runs. But that scenario is getting less likely by the hour.

Stay tuned.