2020 Atlantic Hurricane Outlook issued by Colorado State University

Hurricane Dorian at its peak Image credit NOAA

The Department of Atmospheric Science Colorado State University has issued its “Extended Range Forecast for the 2020 Atlantic Hurricane Season.  

The outlook anticipates that the 2020 Atlantic basin hurricane season will have above-normal activity. The report points to the current warm neutral ENSO conditions to likely transition to cool neutral ENSO or potentially even weak La Niña conditions by this summer and/or /fall with sea surface temperatures over most of the tropical Atlantic warmer than normal. 

 

 

As a result, an above-average probability for major hurricanes making landfall along the continental United States coastline and in the Caribbean is anticipated. Read full report https://tropical.colostate.edu/media/sites/111/2020/04/2020-04.pdf

 

Colorado State 2020 Hurricane Outlook

Posted in Tropical Cyclones | Tagged , , , , | Leave a comment

Hurricane Storm Surges in Tampa Bay

Hurricane Elena NOAA Image

The highest storm surges in Tampa Bay are usually associated with hurricanes, with the three highest tides occurring during Cat 3 storms in 1848, 1921 and 1985.

Hurricane Elena in late August of 1985 caused the highest storm surge recorded at the St. Petersburg tide gauge which has been in operation since Dec. 1946.  Late on the 31st of August the gauge recorded a water level some 4.0 feet above Mean Higher High Water (MHHW) or 6.26 feet above Mean Lower Low Water (MLLW) as Hurricane Elena hovered offshore over the Gulf of Mexico. 

 

The day prior, Hurricane Elena was about 200 miles southeast of the mouth of the Mississippi when it turned eastward. During the next 24-36 hours, the storm moved closer to the west coast of Florida but then stalled about 50 miles off Cedar Key.  At its closest point to Tampa Bay, late on the evening of the 31st, Elena was packing winds to 100 knots making it a Cat. 3 storm. 

Hurricane Elena Track

Due to the slow and erratic motion of this storm, warnings were issued along the Gulf from Sarasota to Grand Island, LA.  All told, 1.5 million people, including about 300,00 in the Tampa Bay area were evacuated. Residents of the Tampa Bay area endured heavy rains and winds, evacuations were ordered and many chose hold-up in shelters. On September 1st, Elena started to move westward again and finally made landfall near Biloxi, Mississippi on Sept. 2nd as a category 3 hurricane.

Earlier Storms
Prior to the tide gauge being installed at St. Petersburg, there were at least 2 incidences of higher surges.  The highest reported storm tide in Tampa Bay occurred in September of 1848 during the “Great Tampa Gale” when the tide was reported to have been 15 feet above low tide or about 12.75 feet above MHHW.  During the October Hurricane of 1921 the tide was reported to have reached 10.5 feet above low water or about 8.25 feet above MHHW.

What about the future?
There have been two Cat 3 hurricanes that have directly impacted the Tampa Bay area since 1848 with the last event in October of 1921, nearly 100 years ago. Although these events are rare they can and will happen again. Based on the above, I would estimate that there is a 1-2% risk for a major hurricane impacting the Tampa Bay area in any given year.  Hurricane Elena, although it did not directly hit Tampa Bay, created a storm surge that was significant. Even though there has never been a Cat. 5 storm to hit Tampa Bay, it is not impossible and the devastation would be extreme.

Project Phoenix
A 2010 study called Project Phoenix funded by FEMA took a look at the Tampa Bay area as if we were hit by a Cat 5 hurricane. In this “worst case” scenario, power outages would be widespread with all of Pinellas County being without power with Pasco and Hillsborough Counties experiencing nearly total power outages as well. The associated storm surge would be as high as 26 feet in Tampa, 24 feet in Apollo Beach, and 20 feet in St. Petersburg. 

Hurricane Phoenix track scenario

All told, the storm could result in up to 2,000 people dead, 2 million injured, and almost 500,000 homes and businesses destroyed.  All three bridges between Tampa Bay and the Courtney Campbell Causeway would “sustain either structural damage or have their approaches washed away by water and waves”

 

Posted in Sea Level Rise, Tropical Cyclones, Weather History, Weather Wisdom | Tagged , , , , , | 2 Comments

Two Major North Atlantic Hurricane-force Storms Expected

Two major hurricane-force storm lows are forecast to develop and move across the North Atlantic during the next 72 hours producing winds up to 80 knots and significant wave heights to 17 meters (over 55 feet)!  This will be a significant challenge to shipping between ports in Northern Europe and the USEC ports.  

Rapidly deepening storm south of Newfoundland 12Z 12 Feb 2020:

By 12Z 13th Surface forecast shows a deepening storm of 944 mb with winds to 80 knots over the main shipping lanes. In addition a second storm is expected to develop along the US East Coast.  

Surface Forecast 12Z 13 Feb 2020

NOAA OPC 12z 13 Feb Significant wave forecasts showing waves to 15.5 meters (over 50 feet)!  

NOAA OPC Significant Wave Height Forecast

NOAA OPC Surface forecast for 12Z 14th Feb shows the deep 936 mb low becoming semi-stationary southwest of Iceland while a second rapidly deepening low is moving northeastward well east of Newfoundland deepening rapidly to 924 mb by 15th. 

NOAA OPC Surface Forecast 12Z 14 Feb 2020

By 12Z 14th significant wave heights are forecast to 17 meters (over 55 feet) west of Ireland. 

NOAA OPC Significant wave height forecast 12Z 14 Feb 2020

Learn more about these winter hurricane storms

Posted in Ocean Storms | Tagged , , , , | Leave a comment

Hurricane-Force Storm expected over Gulf of Alaska

NOAA OPC Surface Forecast 12Z 28 Jan 2020

A rapidly deepening storm low is forecast over the east-central North Pacific during the next 48 hours then moving northeastward over the Gulf of Alaska. This storm will produce storm to hurricane force winds (50-65 knots) and seas building to 14 meters (45 feet).

NOAA OPC 12Z 29 Jan Surface Forecast

NOAA OPC 48 hr Significant Wave Height Forecast

Posted in Ocean Storms | Tagged , , , | Leave a comment

Hurricane-Force Storm NW of Ireland

An intense winter storm over the eastern North Atlantic northwest of Ireland has been producing hurricane-force winds with significant wave heights to 16 meters (52 feet) west of Ireland.

NOAA OPC Significant Wave Height Analysis 12Z 13 Jan 2020feet).

NOAA OPC Surface Analysis Jan 13, 2020 1200Z

Posted in Ocean Storms | Tagged , , , | Leave a comment

Capsizing and Sinking of Barge Dredge200 and Loss of Workboat R.E. Pierson 2 Pushed by Tugboat Big Jake

The National Transportation Safety Board (NTSB) has determined that the probable cause of the capsizing and sinking of the Dredge200 and the R.E. Pierson 2  in December 2, 2018 was the decision by the tow captain and owner to attempt a transit in forecasted wind and waves that exceeded their original plan for the voyage. A workboat and barge sank, resulting in nearly $2 million in losses.

Although the captain and owner had a discussion regarding a plan for the tow configuration and set a limit of 4-foot seas for the voyage, they proceeded through the canal and into Cape Cod Bay despite knowing that the weather forecast called for seas that exceeded the limits they established for the voyage. 

NOAA Surface Analysis Dec. 2, 2018 1800 UTC

 

 

 

 

 

 

 

 

Read the entire NTSB report Capsizing and Sinking of Barge Dredge200 and Loss of Workboat R.E. Pierson 2 Pushed by Tugboat Big Jake

Marine casualty

Posted in Marine casualty, Weather History | Tagged , , | Leave a comment

Intense Hurricane-Force Storm developing east of Japan

NOAA OPC Surface Analysis

A rapidly deepening storm low over the western North Pacific east of Japan is forecast to reach 944 mb with winds of 55-75 knots and seas building to 58 feet (17.7 meters) over the next 12-24 hours.

West Pacific Hi Res Satellite Image

NOAA OPC 48 Hour Surface Forecast

NOAA 48 Hour Significant Wave Height Forecast

Posted in Ocean Storms | Tagged , , , | Leave a comment

Typhoon Forecast to impact Philippines on Christmas

Tropical Storm Phanfone Satellite image

Tropical Storm Phanfone over the western North Pacific east of the Philippines is tracking westward at 14 knots with max winds about 55 knots.

Conditions favor additional strengthening with max winds reaching near 70 knots within the next 12 hours with landfall over the Philippines expected within 18-24 hours. 

JTWC forecast Track

Posted in Ocean Storms, Tropical Cyclones | Tagged , , , | Leave a comment

Hurricane Force storms over North Atlantic Shipping Lanes

NOAA OPC 48 hour 500 mb forecast chart

A strong 500 mb jet is setting up west to east across the North Atlantic over the next couple of days near 40N latitude. This will favor strong storm development across the main North Atlantic shipping lanes. 

NOAA 48 hour Surface Forecast

Expecting storm to hurricane-force winds and significant wave heights to 16 meters (52 feet) moving eastward from the central North Atlantic towards the Bay of Biscay which will present problems routing ships between North Europe and Mediterranean ports to US East Coast and Gulf ports.

Lean more about using the 500 mb chart at sea.

NOAA OPC 48 hour Significant Wave Height forecast

72 hour Surface Forecast 

NOAA OPC 72 hour Surface Forecast

72 hour Wave Height

NOAA OPC 72 Hour Significant Wave Height Forecast

 

 

 

 

Posted in Meteorology, Ocean Storms, Weather Routing | Tagged , , , , , | Leave a comment

Use of the 500 mb Chart at Sea

The 500mb forecast chart is an excellent tool for mariners to estimate where to anticipate the heaviest sea and swell conditions as well as a guide to the expected surface storm tracks and intensities.  The closer the height contours on the 500mb chart, the faster the upper level wind flow, the stronger the temperature contrasts and the more active is the surface weather below. The development and strengthening of surface lows and the associated bad weather most often occurs on the eastern side of 500mb troughs while surface high pressure and good weather is associated with the western side of these troughs.  Without even looking at the surface pressure charts, a mariner can estimate what areas might be best to avoid.

Today’s 500 mb chart of the North Pacific is a good example.

NOAA OPC 500 mb Analysis Dec 

Note the actual significant wave height analysis 

Click here to read more about using the 500 mb chart at sea.

Posted in Meteorology, Weather Routing, Weather Wisdom | Tagged , , , | 1 Comment