The ICAT Damage Estimator can be used to select and display all historical storms that have made landfall since 1900 within the current computer model forecast range for Earl. The westernmost model prediction has Earl passing over the tip of Massachusetts. Accordingly, the ICAT Damage Estimator selects and displays the historical storms that have passed over the easternmost part of Massachusetts. There have been three: Hurricane Edna of 1954, Tropical Storm Esther of 1961, and Tropical Storm Carrie of 1972.
Edna had a similar track and intensity to Earl’s current forecast. It passed east of North Carolina as a category three hurricane and made landfall over Massachusetts as a category one hurricane. It caused about $40M in damage in 1954, which would equate to about $3.67B if it were to make landfall today. Edna is the 65th most damaging storm in the normalized record.
Using the ICAT Damage Estimator’s export feature, you can overlay Edna’s track with the NHC forecast cone for Earl in Google Earth. The output shows that Edna was about 100 miles west of Earl’s current position on September 7, 1954. It tracked up the coast along the western edge of Earl’s forecast cone. Edna passed about 30 miles east of the Outer Banks and made landfall over eastern Massachusetts. Hurricane Earl’s impact should be less severe than Edna’s if the current track forecast verifies. A deviation to the west would lead to a situation more reminiscent of Hurricane Edna.
Only about 20% of Cape Verde storms eventually make U.S. landfall. This is because most of them are steered around the persistent central Atlantic subtropical ridge, known as the Bermuda High. The further south a Cape Verde storm develops, the less likely it is to be steered away by the Bermuda High. The position and strength of the ridge are also very important. A weaker ridge, positioned further east, typically causes a storm to turn N more quickly. A stronger ridge, positioned further west, can steer a storm toward the eastern U.S.
Because these storms form thousands of miles from their ultimate destination, they have plenty of time to grow and intensify. A majority of the most intense and most damaging tropical cyclones in American history were Cape Verde storms. Displaying the ten most damaging U.S. hurricanes with the ICAT Damage Estimator shows that seven of them were Cape Verde storms.
Hurricane Danielle and Tropical Storm Earl are both considered Cape Verde storms. Danielle tracked far enough north for the Bermuda High to steer it away from North America. Living up to its reputation as a Cape Verde storm, Danielle reached category 4 intensity this morning.
Tropical Storm Earl developed further south than Danielle and therefore has a better chance of eventually making landfall. However, Hurricane Danielle has left a trail of relatively low pressure in its wake, which could cause Earl to follow a similar path around the Bermuda High.
The ICAT Damage Estimator shows that there have been ten U.S. landfalling tropical cyclones that have passed within 100 miles of Earl’s current position. Not surprisingly, four of them are in the top ten of the most damaging historical U.S. storms: the Galveston hurricanes of 1900 and 1915, the Lake Okeechobee hurricane of 1928, and the New England hurricane of 1938. Eight of the ten storms eventually impacted North Carolina as they rounded the subtropical ridge about 1000 miles west of where Danielle is currently moving.
By using the export feature in the ICAT Damage Estimator, you can overlay the NHC 5-day forecast cone with these ten storms. The current forecast calls for Earl to begin its northward turn further east than nine of the ten historical storms that ended up impacting the United States. Hurricane Dianne of 1955 (highlighted in pink below) temporarily turned toward the north near Hurricane Danielle’s current position, but was abruptly forced west due to strong ridging to its north. The current upper-air pattern would not likely support similar behavior for Earl. Climatology and the current atmospheric conditions suggest that Earl has a relatively low probability of making U.S. landfall, though impact is not out of the question. As shown by the ICAT Damage Estimator, the greatest threat in the U.S. appears to be around the Carolinas.
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Hurricane Alex Cumulative Wind History
Below is a collection of satellite and radar images of Hurricane Alex near landfall. Alex was an abnormally well-organized hurricane for this early in the season. A minimum central pressure of 947 mb was recorded within Alex near landfall. A pressure this low usually corresponds to a category 3 or 4 hurricane. Luckily, the storm made landfall before the winds could catch up with the pressure.
Radar from June 30 - 840 PM CDT
Satellite from June 30 - 545 PM CDT
Satellite from June 30 - 515 PM CDT
The two visible satellite images below were taken 7 hours apart. The top image is from 645 AM and the bottom image is from 145 PM. The red dots are the official NHC forecast points from this morning. The first point indicates where Alex was at 6 AM. The second point shows where the NHC predicted Alex would be at noon today. The most recent satellite image shows that Alex’s center (green dot) is further south than was predicted this morning. The red line shows the NHC’s forecast and the green line shows reality. By using “nowcasting,” it becomes obvious that Alex has begun its WNW turn. In fact, the NHC has just shifted their track accordingly as I write this. The tropical cyclone also looks better organized in the most recent image, which indicates that Alex is indeed strengthening.
June 29 - 645 AM MDT
June 29 - 145 PM MDT
Tropical Storm Alex became the first named storm of the 2010 Atlantic hurricane season on June 26th. It made landfall over the southern Yucatan Peninsula early on June 27th and emerged over the Gulf of Mexico about 24 hours later. As of June 28th at 3PM MDT, Tropical Storm Alex is off the western Yucatan Peninsula moving NNW at 5 mph. An upper-level low over the northern Gulf of Mexico is causing Alex’s current NNW movement. This same upper-level low is also inducing some wind shear, which is inhibiting the storm’s development. The low is expected to exit the region, which should allow Alex to strengthen and move more toward the west.
The ICAT Damage Estimator shows that there have been four U.S. landfalling storms within 50 miles of Tropical Storm Alex’s current position since 1900. Tropical Storm Arlene of 1993 was the only one that formed in the month of June. It took a similar track to the current forecast for Tropical Storm Alex, though a bit further north into Texas. Alex is expected to make landfall as a category 1 hurricane, which is stronger than Arlene was with only 60 mph winds at landfall. The expected landfall over rural northeastern Mexico should minimize the damages from this storm. Landfall is still a couple days away though, and there is always a large amount of uncertainty in tropical forecasts this far out.
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