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Category: Tropical

A Frightening Afternoon in 1969

| 3:00 pm August 17, 2014

THIS IS HISTORIC INFORMATION ABOUT 1969’s HURRICANE CAMILLE.  IT IS NOT CURRENT INFORMATION.

On the afternoon of August 17, 1969, an Air Force crew led by Marvin Little penetrated the eye of Camille. One way of estimating the surface winds was to visually observe the sea condition. Their report indicated that it was unlike anything they had ever seen in their training. Dr. Robert Simpson, the head of the National Hurricane Center knew that the training was based on 150 mph. His instinct told him that the winds were probably in the neighborhood of 180 knots (210 mph.)

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He would take the unprecedented step of listing the winds at 190 mph in a special advisory that would prompt action from many people along the coast who had planned to stay put.

And at 3 p.m., a historic advisory was written.  Here is the discussion…

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…And the text of the advisory…

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Hurricane Hunters in Hawaii

| 11:14 am August 7, 2014

The Hurricane Hunters are in Hawaii, but they are not on vacation.

The 53rd Weather Reconnaissance Squadron (Air Force Reserve Hurricane Hunters) have deployed two lanes to Joint Base Pearl Harbor to monitor Hurricane Iselle as it makes landfall tonight and to monitor Hurricane Julio as it passes north of the islands this weekend.

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I always love the Google Earth depictions of the Hurricane Hunter missions, especially since they look like a Lite Brite, a toy from some of our childhoods.

But these two storms mean business and the Hawaiian Islands are battening down.

If Iselle makes landfall as a hurricane on the Big Island tonight, it will be the first landfall of a hurricane since Iniki in 1992. Only three storms have made landfall as full hurricanes in Hawaii since 1950.

The big island has not had a direct landfall from a full hurricane since modern records began in 1950.

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Here is the forecast track for Iselle, showing landfall between 2-3 a.m. CDT, which is 9-10 p.m. Hawaiian time.

Hurricane warnings are in effect for the big island of Hawaii, with tropical storm warnings for the rest of the islands. Flash flood watches are in effect for all of the islands.

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The storm is unusual in that it has battled an environment full of dry air and decent shear to remain a hurricane. Here is an enhanced satellite image of Iselle.

In a bit, we will take a look at the impact being expected in the islands as Iselle approaches and what affects Julio will have over the weekend.

A Quick Check on the Tropics

| 12:15 pm August 3, 2014

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Tropical Storm Bertha is pulling through the southeastern Bahamas late this morning.

It is beginning to make the expected turn to the north that will eventually presage its recurvature away from the United States. The storm is expected to miss Bermuda as well.

It has top winds of 45 mph but is expected to strengthen some later today as it moves over warm water and encounters upper level winds that are a little more favorable for development. It should not reach hurricane intensity (74 mph or higher) though.

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It will pass about 200 miles southeast of Cape Hatteras Tuesday morning as it accelerates northeastward. It will pass a couple of hundred miles southeast of Newfoundland Thursday morning then start the trek across the North Atlantic.

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A trough of low pressure over the Bahamas (not associated with Bertha) is disorganized and does not appear to be a candidate for development.

Update on Bertha

| 11:17 am August 2, 2014

Tropical Storm Bertha continues to move rapidly across the northeastern Caribbean today. Bertha remains rather unorganized, but still has sustained winds of 50 mph. Over the next 24-48 hours, Bertha could intensify some, and she will begin to take a more northerly turn. Heavy rain and gusty winds will be impacting Puerto Rico, the Virgina Islands, and the Dominican Republic today through tonight as Bertha passes nearby.

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Here are the latest specifics on Berta.

…CENTER OF BERTHA PASSING JUST SOUTH OF PUERTO RICO…
…TROPICAL STORM WARNING ISSUED FOR PORTIONS OF THE DOMINICAN
REPUBLIC…

SUMMARY OF 1100 AM AST…1500 UTC…INFORMATION
———————————————–
LOCATION…17.2N 66.7W
ABOUT 90 MI…150 KM SSW OF SAN JUAN PUERTO RICO
ABOUT 230 MI…370 KM ESE OF SANTO DOMINGO DOMINICAN REPUBLIC
MAXIMUM SUSTAINED WINDS…50 MPH…85 KM/H
PRESENT MOVEMENT…WNW OR 295 DEGREES AT 22 MPH…35 KM/H
MINIMUM CENTRAL PRESSURE…1008 MB…29.77 INCHES

Now the important question, where is Bertha heading? As she begins to take a more northerly turn, she will affect the Turks and Caicos Islands, as well as the southeastern Bahamas. Bertha will then begin to take the northeasterly turn and accelerate. She should stay west of Bermuda, and well to the east of the Atlantic Coast of the U.S. mainland. Bertha should remain a tropical storm, but there is a chance for her to reach hurricane strength briefly over the open waters of the Atlantic.

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Bertha Is Born

| 10:09 pm July 31, 2014

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The National Hurricane Center has initiated advisories on Tropical Storm Bertha since showers and storms are building rapidly around the center and the plane encountered tropical storm force winds.

SUMMARY OF 1000 PM CDT…0300 UTC…INFORMATION
———————————————–
LOCATION…12.3N 55.5W
ABOUT 275 MI…445 KM ESE OF BARBADOS
ABOUT 385 MI…620 KM ESE OF ST. LUCIA
MAXIMUM SUSTAINED WINDS…45 MPH…75 KM/H
PRESENT MOVEMENT…WNW OR 290 DEGREES AT 20 MPH…31 KM/H
MINIMUM CENTRAL PRESSURE…1008 MB…29.77 INCHES

Tropical storm warnings and watches have been issued for parts of the Lesser Antilles.

A TROPICAL STORM WARNING IS IN EFFECT FOR…
* BARBADOS
* ST. LUCIA
* DOMINICA

A TROPICAL STORM WATCH IS IN EFFECT FOR…
* PUERTO RICO
* VIEQUES
* CULEBRA
* U.S. VIRGIN ISLANDS
* ST. VINCENT AND THE GRENADINES

Here is the forecast track and cone of uncertainty:

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An Important Anniversary in Hurricane Forecasting

| 3:30 pm July 27, 2014

In July 1943, tracking hurricanes was a difficult business. Fewer ships were at sea because of the threat of German U-boats. Those that were at sea maintained radio silence. Britain suffered mightily from the lack of weather reports from over the Atlantic. The Brits were forced to use precious aircraft to fly weather observation missions. The U.S. feared that the West Indies would become a major theater of war if the Germans decided to attack through Central and South America.

In Bryan, Texas, Col. James P. Duckworh was in charge of the Instrument Flying Instruction School. Before the 1930s, there wasn’t any such thing as instrument flying. Everything was visual. Duckworth had been a pilot for Eastern Air Transport, the precursor to Eastern Airlines. He had resigned to go to active duty with the Army Air Corps Reserve. Duckworth said that he knew that the war wasn’t going to stop because of weather.

Weather map from the morning of July 27, 1943.

Weather map from the morning of July 27, 1943.

On the morning of Sunday, July 27th, Col. Duckworth made his way to the base to have breakfast. As he ate, he learned that there was a hurricane making landfall near Galveston. Hard to believe, since it was a beautiful morning at Bryan, about 100 miles from Galveston. The storm was expected to pass near Houston during the afternoon. Duckworth saw it as the perfect opportunity to do what no one had done intentionally up to that time: fly into a hurricane.

Joe suggested to one of his breakfast companions, Lt. Ralph O’Hair that they take an single engine AT-6 trainer and fly into the storm for fun. There were four new B-25‘s at the base, but it would be hard to justify using one of them for this unsanctioned mission. As 100 mph winds were raking the coast. Duckworth and O’Hair took off for Galveston. Enroute, they called the tower at Houston and said they were flying Galveston. The incredulous operator asked them if they knew there was a hurricane. When they said yes, the controller asked for updates so he would be able to direct crews to the wreckage.

As they flew toward the hurricane, they were in the weaker western semicircle of the storm. As they neared the eyewall, they experienced violent up and down turbulence that made them feel like a “bone in a dog’s mouth”. Suddenly, they broke into the clear air of the eye. They flew around for a few minutes and headed back to the base where they were met by the staff meteorological officer. The weatherman wanted to know why they had not included him in their historic flight. They responded by telling him to hop in, they would take him to the center. The meteorologist kept a very detailed diary of observations.

Duckworth did not immediately realize the significance of his feat. Later that year, one of his superiors summoned him to tell the pilot that he had been recommended for the Distinguished Flying Cross. The unassuming Colonel did receive the Air Medal for flying into a hurricane for the first time, twice in the same day.

Realizing the benefit of more specific information on hurricanes, regular reconnaissance flights were started the next year. Weather Bureau meteorologists used the information about 1944’s Great Atlantic Hurricane to issue better warnings.

Tropics Quiet…For Now…

| 2:00 pm July 27, 2014
Tropical Storm Bertha next Saturday evening?

Tropical Storm Bertha next Saturday evening?

We are tracking a tropical wave in the far eastern Atlantic on this last Sunday of July.

Right now it doesn’t look like much, but several of the global models, including the American GFS and the UKMET are now on board with the idea that it will become tropical depression number 3 in the week ahead as it steams across the Atlantic. There is a chance it could even go on to become Tropical Storm Bertha.

It is expected to move near the northern Lesser Antilles or Virgin Islands Friday night and could affect Puerto Rico as well. After that, the GFS currently projects it curving around the Bermuda High and flirting with the U.S. East Coast, but not making landfall.

Another system will come off the African coast late in the week, but indications are that it will head toward weakness over the western Atlantic as the subtropical high shifts a little east temporarily.

Is Tropical Depression #2 About to Form?

| 11:49 am July 21, 2014

The National Hurricane Center has given the designation over the Central Atlantic a designation (92L). Convection has developed near the center and it appears to have a circulation. It is in an area of low wind shear, that is favorable for development.

vis_lalo-animated 92L

It could become Tropical Depression #2. The NHC gives it a 50% chance of that happening.

It will likely weaken though as it encounters more hostile conditions as it approaches the islands. It still will bring squally weather to them Wednesday night and Thursday.

There is some chance it could flare back up as it nears the United States, so we will be watching!