• Chuck Lanza

Tropical Storm Elsa Briefing #4 July 3, 2021

Updated: Jul 9

Observations:At 5:00 am the National Hurricane Center Discussion remarked that later in the morning an Air Force Reserve Hurricane Hunter aircraft and team would be flying Elsa; I opted to wait until the Hurricane Hunter's data was included in the forecast. At the 11:00 am Advisory, with the addition of the Hurricane Hunter's data, Elsa has been downgraded to a Tropical Storm. The Hurricane Hunter found Elsa to be less organized with maximum sustained winds of 70 mph. It is difficult for a storm to remain organized and maintain or even increase wind speed when moving at 29 mph. I liken it to riding in a car with your hand outside the window, as the car's speed increases your hand starts to move more erratically. Elsa does not have any hands but I hope you get the picture.


Elsa is forecasted to exit the north coast of Cuba sometime Monday as a Tropical Storm. In the first graphic the three day cone (the white shaded area of the Cone of Probability) forecasts a Tropical Storm near Key West on Monday evening and moving north-northwesterly to an area west of southwest Florida on Tuesday morning.


Some of the track models are shown below. There is better agreement on the general path for this group of models and the NHC's forecast is about in the center of the models.


Most of the intensity models rest between Elsa remaining a Tropical Storm while only a couple of outliers are showing Elsa as Category 1 Hurricane.


The fourth graphic is the Probability of Tropical-Storm-force Wind Speed Probabilities where we can see wind speed probabilities for any area in the Cone of Probability. Looking at the graph we can discern that the current forecast for Tropical Storm Force Winds near Key West is 50-60 percent. while the southern 3/4 of the west coast of Florida is 40-50 percent. Southeast and east central Florida have a 10 to 20 precent. A text version of this graphic can be found here.


At the request of several people, I added a few more Governmental and Private Sector Weather related sites below. You will see more as Elsa tracks towards Florida. They will be appropriate to our stage of preparedness and response and will support the Protective Action Recommendations (PARs).


As a reminder, a complete update to the NHC advisories is released daily at 5am, 11am, 5pm and 11pm. These are usually the most important and anticipated. Between these times at 2am, 8am, 2pm and 8pm there are advisories with less information usually just an update to the storm's current location. I will provide at least one briefing daily until the threat has passed. I read all the advisories but will usually only brief on the 5am, 11am, or 5pm. If there are any major changes to the forecast I may add another briefing. My preference is to brief after the 5am, 11am or the 5pm.


The first and fourth graphics are from the National Hurricane Center

while the second and third graphics are from the website by Levi Cowan - tropicaltidbits.com Information from the National Hurricane Center Center:

(Click the graphic to go to the site)Other helpful related sites:

(Click the graphic to go to the site)






Protective Action Recommendations (PARs):

As was stated in the Observations and the Key Messages sections above, close monitoring is in order. Elsa is now a Category One Hurricane. There is a great deal of time, distance, warm waters and land mass between us a the storm. Which means we can expect many changes before next week. Based on what I see, I have verified my generator is working well, potable water and food are readily available for there days. On any day, I have at least three days of food and water not necessarily as preparedness but my desire to stay out of the stores as much as possible. For those of you who are new to the area or to these briefings, I will include some important sites and contacts I use. If the municipality or county, in which you reside, offers inclusion on an emergency notification systems, be sure to join. Be safe and keep up to date on the tropics.


I included a link below with the definition of Cone of Probability. It is a common hurricane term which is misunderstood more than it is understood. The NHC has dealt very well with this definition. Helpful links: Hurricane Related Definitions

Cone of Probability


Important Government Weather Related Sites

National Hurricane Center website.

NWS Weather.Gov

National Weather Service-Miami

National Weather Service-Melbourne

FEMA Hurricane page

Florida Division of Emergency Management (FDEM)

Ready South Florida

Important Non-Government Weather Related SitesFlorida Power and Light Storm Center

More to Follow

Disclaimer: I take every precaution to provide timely and accurate information from the National Hurricane Center, National Weather Service and support organizations. Please use the information provided here as a supplement to the forecasts and recommendations presented by hurricane and weather professionals as well as government officials. Please share these briefings with friends, colleagues and relatives. I will strive to keep the briefings succinct, robust and timely. Thank you. Chuck

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